ÿþ<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html><head><title>ESITO Schedule</title> <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"> <style type="text/css"> <!-- .style16 {font-weight: bold; color: #FF0000;} .style17 { color: #008040; font-weight: bold; } .style3 {font-size: 24px} .style4 {font-size: 5px} .Stile1 {font-size: 16px} --> </style> <link href="email_link.css" rel="stylesheet" type="text/css"> </head> <body style="background-color: rgb(255, 255, 255);"> <table align="center"> <tr> <td rowspan="3"><img src="ESITO7.jpg" alt="" border="0" height="200" width="200"> </td> <td height="91"> <br /> <p><b><font face="Times New Roman, Times serif" size="6">ESITO XII</font></b></p> <p><b><font face="Times New Roman, Times, serif" size="+3">European Symposium for</font></b></p> <p><b><font face="Times New Roman, Times, serif"><font size="+3">Insect Taste and Olfaction</font></font></b></p> </td> </tr> </table> <p> </p> <hr> <h3 style="margin:0px; font-size:28px;">12th ESITO</h3> <p style="margin:0px; font-size:16px;"><span class="style3">September 19-25, 2011</span><br> <strong> Hotel Repinskaya, Saint-Petersburg, Russia</strong><br> </a></p> <h2 style="font-size:28px;">Abstracts&nbsp;</h2> <HR> <p><span class="style16">1<br> <br> Zsolt Karpati<sup>1</sup>, Marco Tasin<sup>2</sup>, Charoula Christopoulou<sup>3</sup>, Ring T. Carde<sup>4</sup>, Teun Dekker<sup>3</sup> </span><br> <br> 1 Max Planck Institute for Chem. Ecol., Dep. of Evol. Neuroethol. Hans-Knoell-Strasse 8, D-07745 Jena, Germany<br> 2 Research and Innovation Centre, Edmund Mach Foundation-IASMA, Via E. Mach 1, 38010 S. Michele all'Adige (TN), Italy<br> 3 Div. of Chem. Ecol., Swedish Univ. of Agric. Sci., PO Box 44, SE-230 53, Sweden<br> 4 Deptartment of Entomology, University of California, Riverside, CA 92521, USA </p> <a href="mailto:zkarpati@ice.mpg.de.ch"> zkarpati@ice.mpg.de.ch</a></p> <p class="style17">Blend blindness during pheromone orientation in the European corn borer</p> <p>The European corn borer with two pheromone strains (Z, E), is a good model species of reproductive isolation based on chemosensation. The Z-strain males respond to a ratio of 97:3 of Z11-tetradecenyl acetate and E11-tetradecenyl acetate, while the E-strain prefers almost the opposite ratio (1:99). Male pheromone preference is a major factor contributing to reproductive isolation of the two strains as wind tunnel studies demonstrate that cross-strain attraction is nearly zero. Yet, hybrids can be found where the two strains occur in sympatry, which is surprising considering male blend selectivity. We conjectured that in sympatry a male moth may be confronted with overlapping plumes of different composition, a situation we simulated in the wind tunnel. We found that the specificity of the males decreases when plumes of their own strain are interlaced with other plumes, in other words they land on the other strain s source. The experiments also indicate that selectivity differs between the various behavioural steps leading to source finding, i.e., males are not equally sensitive to the blend ratios in the different stages in the orientation process. Detailed flight analyses with swapping pheromone plumes demonstrate that males may not be as sensitive to the blend ratio once locked onto the plume. Taken together the results indicate that in the field hybridization rates increase as a function of population density. Possible causes of the observed  blend blindness are discussed.</p> Supported by Carl Trygger Stiftelse CTS 06:94 and 07:77 grants, the ICE<sup>3</sup> Linnaeus grant to the division of Chemical Ecology, FORMAS grant 2007-1491, and a Marie Curie IEF (255193) grant and Max Planck Society. </p> <hr> <p class="style16">2<br> <br>Stengl Monika, Flecke Christian, Andreas Nolte, Petra Gawalek</p> <p>University of Kassel FB Mathematics and Natural Sciences, Biology, Animal Physiology; Heinrich Plett Str. 40; 34132 Kassel, Germany.<br> <br> <a href="mailto:stengl@uni-kassel.de"> stengl@uni-kassel.de</a></p> <p class="style17">Pheromone-transduction cascades employed in antennal sensilla of the hawkmoth <em>Manduca sexta</em> depend on Zeitgebertime and stimulus concentration</p> <p>Pheromone transduction cascades employed of olfactory receptor neurons (ORNs) innervating long trichoid sensilla of the moth's antenna are still under debate. Since the discovery of inverted insect 7TM-olfactory receptors and a conserved olfactory coreceptor it was suggested that possibly an ionotropic next to or instead of a metabotropic cascade governs pheromone transduction. Based on patch clamp recordings of cultured ORNs <em>in vitro</em> and tip recordings of the intact moth <em>in situ</em> we provide evidence that different interacting metabotropic signal transduction cascades are employed in bombykal-sensitive ORNs of <em>M. sexta</em>, which depend on pheromone concentrations, on the Zeitgebertime, and on the physiological state of the moth. During the night, when the moths are actively searching for females phospholipase C&beta;-dependent signal transduction cascades are employed activating directly or indirectly IP<sub>3</sub>-dependent transient Ca<sup>2+</sup>-channels and Ca<sup>2+</sup>-dependent cation channels causing rapid and transient rises of intracellular Ca<sup>2+</sup> concentrations. In addition, high concentrations of the stress hormone octopamine elevate intracellular cAMP-concentrations and allow for sensitive, phasic pheromone responses. Longer pheromone stimuli DAG-dependently activate protein kinase C which appears to underly mechanisms of short-term adaptation while even longer, stronger pheromone stimuli cause rises in cGMP, underlying long-term adaptation with even more tonic, less sensitive pheromone responses, as they also occur during the rest phase of the moth, during the day. [Supported by DFG STE531-20-1]</p> <hr> <p class="style16">3<br> <br>Geronimo L. Galvani<sup>1</sup>, Arturo H. Roig-Alsina<sup>1</sup>, Beatriz P. Settembrini<sup>1,2</sup></p> <p>1 Museo Argentino de Ciencias Naturales, Avenida Angel Gallardo 470, C1405DJR, Ciudad de Buenos Aires, Argentina.<br> 2 Facultad de Ciencias Biomedicas, Universidad Austral, Presidente Peron 1500, B1629AHJ, Pilar, Provincia de Buenos Aires, Argentina<br> <br><a href="mailto:geronimogalvani@hotmail.com"> geronimogalvani@hotmail.com</a>, <a href="mailto:galvanigeronimo@macn.gov.ar"> galvanigeronimo@macn.gov.ar</a></p> <p class="style17">Morphology and distributional pattern of antennal sensilla in solitary bees (Hymenoptera, Apidae)</p> <p>We have studied the morphology and distributional pattern of antennal sensilla in bees of the tribes Epeolini, Protepeolini, Emphorini, Exomalopsini and Eucerini (Family: Apidae) in order to correlate the antennal structure with the different types of behavior, and to provide new taxonomic characters for these groups. Both sexes have been studied. The species of the tribes Emphorini, Exomalopsini and Eucerini are pollen-collecting solitary bees, the females of which are frequently oligolectic (Bee or genera that specialize on a particular pollen taxon). Members of the tribes Epeolini and Protepeolini are cleptoparasites (the females do not collect pollen and lay their eggs on the provisions of other bees). Male bees are not involved in breeding the offspring. We have identified the types of antennal sensilla and setae, as well as analyzed the distribution of these cuticular structures on the antennal flagellum, which were classified in six types according to their morphology: placodea, trichodea, basiconica, coeloconica, ampullacea and coelocapitular. In bees, sensilla trichodea have been further divided into subtypes A (stA), B (stB) and C-D (stC-D). Morphological and physiological studies suggested that sensilla placodea and stA are olfactory receptors, stB are tactile receptors, stC-D and basiconica are gustative receptors, coeloconica are thermal receptors, ampullacea are CO<sub>2</sub> receptors and coelocapitular are higroreceptors. We have recognized four patterns of spatial distribution on the dorsal part of flagellomeres 4-10 in the tribes Emphorini, Exomalopsini and Eucerini; only in females of Emphorini are the four patterns present. On the other hand, in species of the tribes Epeolini and Protepeolini the dorsal part of flagellomeres 4-10 lacked setae. Epeolini and Protepeolini showed the highest density of stA, as well as a number of sensilla stB and stC-D lower than in the pollen-collecting tribes. Within members of the tribe Emphorini, Exomalopsini and Eucerini, females showed a number of stB and stC-D higher than males, instead stA were more abundant in males. No significant difference was found in the number of sensilla placodea, ampullacea, coeloconica and coelocapitular, with the exception of males of Eucerini, which showed the highest of number of sensilla placodea. Basiconic sensilla were not found on the females of Epeolini and Protepeolini, nor on any male of all the species studied. These results suggest that the antennae of cleptoparasitic species have a greater abundance of olfactory hairs, while setae, gustative, and tactile sensilla are poorly represented. Furthermore, males and females displaying this behavior have similar values of all types of antennal sensilla. The antennae of oligolectic female bees have a higher proportion of gustative and tactile than those of males. All the samples from oligolectic bees showed sexual dimorphism in antennal sensilla. These data suggest a relationship between the presence of gustative and tactile receptors and the different tasks of pollen collecting and nest building. The variety in the spatial distributions of setae here described for Emphorini bees, suggests that these cuticular structures may be useful in taxonomy.<br>Supported by PICT 2007-1238</p> <hr> <p class="style16">4<br>Paul Szyszka and C. Giovanni Galizia</p> <p>Neuroscience, Universit&auml;t Konstanz, D-78457 Konstanz, Germany<br> <br><a href="mailto:paul.szyszka@uni-konstanz.de"> paul.szyszka@uni-konstanz.de</a> </p> <p class="style17">Trace memory and memory traces in the insect brain - behavior and physiology</p> <p>Memory traces can be revealed behaviorally by classical conditioning where a neutral stimulus (conditioned stimulus, CS) is associated with a following meaningful stimulus (unconditioned stimulus, US). In most cases, classical conditioning works best when the CS and US overlap (delay conditioning). However, classical conditioning also works with a stimulus-free gap between CS and US (trace conditioning). Thus, a post-stimulus neural representation (trace) of the CS is required to bridge the gap until its association with the US. Associative learning, therefore, relies on multiple memory traces: associative CS-US memories and non-associative sensory stimulus traces. We performed trace conditioning experiments in honey bees with odor as CS and sucrose reward as US to characterize the properties of associative CS-US memories (trace memory), and the properties of the non-associative CS trace. Moreover, we investigated the effect of associative learning on early sensory processing, by combining delay conditioning with in vivo calcium imaging of secondary olfactory neurons, the projection neurons in the honey bee antennal lobe. We found that odor traces decay in time, but can be extended by experience, showing that trace conditioning itself can be learned, and is not a simple reflex learning. Furthermore, bees  unlike mammals  form a trace already after a single trace conditioning event. Finally, we show that calcium activity in projection neurons does not represent the trace substrate. Rather, the trace must be searched for in other second messengers, or in other brain areas, such as the mushroom bodies. Projection neuron calcium activity, however, contains a memory trace 2 to 5 hours after delay conditioning. This memory trace appears as change in neural odor representations which can be traced back to glomerulus-specific neural plasticity, which depends on the glomerulus` response profile before training. The data is consistent with a neural network model of the antennal lobe, which we based on two plastic synapse types and two well-known learning rules: associative, reinforcer-dependent Hebbian plasticity at synapses between olfactory receptor neurons and projection neurons, and reinforcer-independent Hebbian plasticity at synapses between local interneurons and olfactory receptor neurons. Taken together, our data suggest that olfactory trace conditioning is a less reflexive form of learning than classical delay conditioning, indicating that odor traces might involve higher-level cognitive processes, and that odor learning optimizes odor representations and facilitates the detection and discrimination of learned odors.<br> Supported by Bundesministerium für Bildung und Forschung (BMBF) (01GQ0771 to C.G.G. and 01GQ0931 to P.S. and C.G.G.) and Deutsche Forschungsgemeinschaft (DFG) (GA524/8-1 and GA524/12-1 both to C.G.G.).</p> <hr> <p class="style16">5<br> <br>Pablo Pregitzer<sup>1</sup>, Silke Sachse<sup>2</sup>, Heinz Breer<sup>1</sup> and Jürgen Krieger<sup>1</sup></p> <p>1 University of Hohenheim, Institute of Physiology, 70599 Stuttgart, Germany<br> 2 Max Planck Institute for Chemical Ecology, Department of Evolutionary Neuroethology, 07745 Jena, Germany<br> <br><a href="mailto:juergen.krieger@uni-hohenheim.de"> juergen.krieger@uni-hohenheim.de</a></p> <p class="style17">Mechanisms of pheromone detection in <em>Heliothis virescens</em></p> <p>The remarkable ability of male moths to detect accurately very low concentrations of female-released sex pheromone is based on specifically tuned olfactory  hairs on the antennae. These sensilla trichodea house the dendrites of olfactory sensory neurons (OSNs) each endowed with distinct pheromone receptors in their membranes. The dendrites are bathed in aqueous sensillum lymph containing high concentrations of pheromone binding proteins (PBPs), which are supposed to capture the hydrophobic pheromones from the air and to mediate the transfer towards the pheromone receptors. <em>Heliothis virescens</em> females use a complex pheromone blend for mate attraction, with Z11-hexadecenal as the major component. Previously, we have identified a group of relatively conserved pheromone receptors of Heliothis virescens. Using heterologous expression systems we could show that the receptor type HR13 was activated by Z11-hexadecenal; the response was mediated by an interplay with PBP2. In addition, FISH-experiments revealed that antennal cells, which express HR13 also express the  sensory neuron membrane protein 1 (SNMP1) as well as the olfactory co-receptor Hvir\Orco. All HR13 cells were found to be surrounded by support cells expressing PBP2. Taken together these results suggest that PBP2, HR13 as well as SNMP1 and Hvir\Orco may contribute to specific responsiveness of antennal OSNs to the major component of the female pheromone blend. In ongoing studies, attempts are made to reconstitute the identified olfactory proteins in heterologous systems in order to explore the specific role of each element and to approach a possible interference of pheromone detection with plant-derived odorants coexisting in the environment of calling females. To approach the question if a peripheral interplay between Z11-hexadecenal and odorants at the OSNs level may have consequences for the processing in the brain, <em>in vivo</em> imaging experiments are performed monitoring the activity in the pheromone-processing macroglomerular complex (MGC) and odorant-processing glomeruli in the antennal lobe of males.</p> <p>This work was supported by the Deutsche Forschungsgemeinschaft.</p> <hr> <p class="style16">6<br> <br>Debora Fusca<sup>1</sup>, Susanne Neupert<sup>2</sup>, Joachim Schachtner<sup>3</sup> Reinhard Predel<sup>2</sup>, and Peter Kloppenburg<sup>1</sup></p> <p>1 Biocenter Cologne, Institute for Zoology, Center for Molecular Medicine Cologne (CMMC), and Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Zülpicher Str. 47b, 50674 Cologne, Germany<br> 2 Institute for Zoology, University of Jena, Erbertstrasse1, 07743 Jena, Germany<br> 3 Animal Physiology, University of Marburg, Karl-von-Frisch Str. 8, 35043 Marburg, Germany<br> <br><a href="mailto:debora.fusca@uni-koeln.de"> debora.fusca@uni-koeln.de</a></p> <p class="style17">Peptide inventory of identified local interneurons in the antennal lobe of <em>Periplaneta americana</em></p> <p>In the insect antennal lobe (AL) local interneurons (LNs) mediate complex excitatory and inhibitory interactions between the glomerular pathways to structure the olfactory representation. LNs have distinct morphological and intrinsic electrophysiological properties, and in addition to GABA and acetylcholine LNs may contain and release various peptides. In Periplaneta americana we identified two main LN types: 1) Spiking type I LNs that generated Na+ driven action potentials upon odor stimulation and exhibited GABA-like immunoreactivity (GABA-LIR) and 2) non-spiking type II LNs with unknown transmitter that generate Na+ driven action potentials. Nonspiking type II LNs exist in at least two sub-types (type IIa and type IIb). Type IIa LNs had strong Ca<sup>2+</sup> dependent active membrane properties and responded with odor specific elaborate patterns of excitation that include the generation of Ca<sup>2+</sup> driven 'spikelets' in 30% of the neurons. In contrast, type IIb LNs responded mostly with sustained, relatively smooth depolarizations. <br>Currently, the morphologically and physiologically distinct LN sub-types are not very well matched with the variety of peptide. This, however, would be extremely important to better understand the role of olfactory LNs, because their marked physiological differences imply consequences for their computational capacity, synaptic output kinetics, and thus their function in the olfactory circuit. <br>To analyse the neuropeptide inventory of the P. americana AL, we used a combination of immunocytochemistry and of defined AL soma groups to reveal the spatial distribution of neuropeptide containing cells. Based on these date we have started to match the identified LN types with their peptide profiles, by using mass spectrometric profiling, whole-cell patch-clamp recordings and single cell stainings combined with immunocytochemistry. <br>This work was supported by grants of the Deutsche Forschungsgemeinschaft to PK, JS, and RP. <hr> <p class="style16">7<br> <br>Olsson, SB<sup>1</sup>, Rácz, Z<sup>2</sup>, Bula, WP<sup>3</sup>, Dimov, N<sup>3</sup>, Carot-Sans, G<sup>4</sup>, Jordan, MD <sup>5</sup>, Karout, S<sup>5</sup>, Kuebler, LS<sup>1</sup>, Markovic, D<sup>5</sup>, Muñoz, L<sup>4</sup>, Pathak S<sup>2</sup>, Challiss, J<sup>5</sup>, Cole, M<sup>2</sup>, Gardner, JW<sup>2</sup>, Gardeniers, JGE<sup>3</sup>, Guerrero, A<sup>4</sup>, Hansson, BS<sup>1</sup>, and Pearce, TC<sup>5</sup></p> <p>1 Dept. of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, Jena, Germany<br> 2 School of Engineering, University of Warwick, Coventry, United Kingdom<br> 3 MESA+ Institute for Nanotechnology, University of Twente, Enschede, The Netherlands<br> 4 Dept. of Biological Organic Chemistry, Institute of Advanced Chemistry of Catalonia, (CSIC), Barcelona, Spain<br> 5 University of Leicester, Leicester, United Kingdom<br> <br><a href="mailto:solsson@ice.mpg.de"> solsson@ice.mpg.de</a></p> <p class="style17">iChem: An insect-inspired biomimetic infochemical communication system</p> <p>The incredible selectivity and sensitivity found in the world of insect chemical communication provides an ideal template to develop technologies capable of fast, high bandwidth transfer of information. In a novel approach to information and communication technologies, we have developed a new communication system based on the chemical signaling of moths. Through the symbiosis of biology and engineering, we have established functional equivalents of the molecular, subcellular and cellular machinery comprising the pathway between pheromone production and detection in the Egyptian armyworm, <em>Spodoptera littoralis</em>. Both signal generation and reception were investigated using a systematic approach with defined biosynthetic modules that were integrated as a technological solution for machine-based  infochemical communication . These modules were defined as hydrocarbon chain shortening, desaturation, functional group modification (Figure 1: chemoemitter), receptor protein binding/transduction and central processing (chemoreceiver). The chemoemitter was realized using a diacylglycerol acyl transferase from <em>Acinetobacter sp.</em> (a wax ester synthase) immobolized in a microreactor to convert the alcohol precursor of the major pheromone component into the corresponding acetate. This synthetic product was then volatilized from a black silicon evaporator, or  artificial gland , capable of continuous flow injection and surface heating. The efficacy of the chemoemitter was assessed via electroantennographic detection on male <em>S. littoralis</em> antennae. In parallel, the functional layer of the chemoreceiver biosensor comprised heterologously-expressed olfactory receptors in SF9 cells coupled to a surface acoustic wave sensor. The signals generated from a differential sensor system were processed using models of moth antennal lobe blend processing implemented in neuromorphic processors. This unique combination of pheromone biochemistry, microreactor technology, bioengineering, and neuroscience forms the basis of a new branch of information technology employing chemicals to encode multiple channels of information and communicate over space and time. <p> <IMG SRC="olsson.jpg" WIDTH=700 HEIGHT=250 BORDER=0 ALT="IMAGE" ALIGN=bottom><br> Figure 1. Biosynthetic Infochemical Communication System <p>Funding provided by the 6th framework program of the EU (iChem)<hr> <p class="style16">8<br> <br>Jennifer S. Ignatious Raja<sup>1</sup>, C. Giovanni Galizia<sup>1</sup>, and Vladimir L Katanaev<sup>2</sup></p> <p>1 Department of Biology, University of Konstanz, D78457 Konstanz, Germany<br> 2 Department of Pharmacology and Toxicology, University of Lausanne, CH-1015 Lausanne, Switzerland<br> <br><a href="mailto:jennifer.ignatious-raja@uni-konstanz.de"> jennifer.ignatious-raja@uni-konstanz.de</a></p> <p class="style17">Odor response profiles of <em>Drosophila</em> olfactory receptors from heterologous expression in HEK293 cells</p> <p>Olfaction plays a major role in insects and mediates behavioral and physiological responses. <em>Drosophila</em> is an excellent model insect to study various biologically important aspects of olfaction. For these studies the odor response profile of all odorant receptors (ORs) to a wide range of odor molecules should be known. Though Drosophila ORs were studied extensively, still the olfactome is not complete. In order to study the odor response profile of dORs, we expressed dORs (Or22a & Orco) in a heterologous cell system (Human embryonic kidney (HEK293) cells). The transfection efficiency of dORs was about 50-60% and the majority of the transfected cells (greater than 80%) responded to the odor by increasing the levels of intracellular calcium. Calcium response to the odor was transient and reproducible and required co-expression of Orco. The calcium response of individual cells in a population was analyzed semi-autonomously by using the user defined workflows in the open source software  KNIME (Konstanz Information Miner - http://www.knime.org/). This image analysis method is robust and faster than other methods. By this method we aim at characterizing the odor response profile of all dORs whose response profiles are as of yet unknown. <hr> <p class="style16">9<br> <br> Chen-Zhu Wang</p> <p>State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100080, China<br> <br><a href="mailto:czwang@ioz.ac.cn"> czwang@ioz.ac.cn</a></p> <p class="style17">Coding of Sex Pheromone Blends with Reverse Ratios in Two Helicoverpa Species and Its Inheritance Pattern</p> <p>The two sibling sympatric species, <em>Helicoverpa armigera</em> (Hübner) and <em>Helicoverpa assulta</em> Guenée (Lepidoptera: Noctuidae) share two major sex pheromone components, cis-11-Hexadecenal (Z11-16:Ald) and cis-9-Hexadecenal (Z9-16:Ald), but in almost reversed relative concentrations, 100: 2.1 and 5.8:100 respectively. In the laboratory, reciprocal hybridization between the two species followed by backcrossing of the hybrids (F1) with <em>H. armigera</em> produced backcross (BC) lines consisting of partial fertile females and males. Thus, isolation between <em>H. armigera</em> and <em>H. assulta</em> is caused by a combination of several prezygotic and postzygotic factors. Here we report about coding of their sex pheromone blends with reverse ratios in males and its inheritance pattern. Our behavioral and electrophysiological results show that the pheromone coding in <em>H. armigera and <em>H. assulta</em> </em> mainly occurs in two types of highly specific receptor neurons in two types (A type and C-type) of antennal sensilla, which recognize the two-components of the pheromone blend. In A type sensillum the neuron responds to Z11 16:Ald, and in C-type sensillum the neuron responds to Z9 16:Ald. As labeled lines, the two neurons each send unique information based on their firing rate, and continuously signal to the antennal lobe the levels of Z11 16:Ald and Z9 16:Ald in the air. The different sensitivity, abundance and distribution of the neurons in the two species further increase the differences between the two signals, reflecting the importance of pheromone components in the pheromone system of these two species. We focus on the olfactory receptors and associated transduction molecules to study their contributions to the specificity and sensitivity of relative neurons to the signals. The genetic architecture of pheromone coding at the periphery is quite complex, and the alleles of <em>H. armigera</em> seem to be dominant or partially dominant over those of <em>H. assulta</em>. The projection of the axons of receptor neurons to the male specific macroglomerular complex (MGC) in the antennal lobe was reported to be also different between the two species. The central nervous system may use a simple mechanism to compare the paired input, and accordingly trigger the appropriate behavior.<hr> <p class="style16">10<br> <br> Yun-Feng Zhang, Ling-Qiao Huang*, Chen-Zhu Wang</p> <p>State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100080, China<br> <br><a href="mailto:huanglq@ioz.ac.cn"> huanglq@ioz.ac.cn</a></p> <p class="style17">Tarsal Contact Chemoreception to Sinigrin as a Deterrent on Feeding and Oviposition of Two Sister Species of <em>Helicoverpa</em> with Different Host Ranges</p> <p>Effects of a crucifer allelochemical, sinigrin on feeding and oviposition of adult female of generalist <em>Helicoverpa armigera</em> and specialist <em>Helicoverpa assulta</em> were studied in the laboratory, and the taste sensilla involved in the perception of sinigrin were investigated. The behavioural bioassays indicated that sinigrin at 10 and 100 mmol l<sup>-1</sup> inhibited the proboscis extension reflex (PER) and deterred feeding in both species. Sinigrin at 47.5 ¼mol/g in the filter paper also inhibited oviposition in the two species, but such effect disappeared when forelegs were treated with HCl. We could not observe major differences in these effects between the two species. Electrophysiological measurements showed that among a total of 14 contact chemosensilla on each ventrolateral side of the fifth tarsomere of forelegs, 8 sensilla in <em>H. armigera</em> and 9 in <em>H. assulta</em> strongly responded to sinigrin at 100 mmol l-1. All these sensilla responded in a dose-dependent fashion and exhibited a typical tonic firing pattern of a deterrent cell. In <em>H. assulta</em>, all the 9 sensilla from the proximal to the terminal were highly and equally sensitive to sinigrin. However, in <em>H. armigera</em>, the proximal 4 sensilla were highly sensitive, but the terminal 4 sensilla were less sensitive. We conclude that sinigrin is a key deterrent on feeding and oviposition in both species and that tarsal contact chemosensilla play an essential role in sinigrin perception. The distribution and sensitivity of the deterrent cells may reflect the host-plant range patterns of two species interrelated with cruciferous plants.<hr> <p class="style16">11<br>Ulrike Pech, Atefeh Pooryasin, André Fiala</p> <p>Department of Molecular Neurobiology of Behavior, Johann-Friedrich-Blumenbach-Institute for Zoology and Anthropology, Georg-August-University of Goettingen<br> <br><a href="mailto:Ulrike.Pech@biologie.uni-goettingen.de "> Ulrike.Pech@biologie.uni-goettingen.de </a></p> <p class="style17">Optogenetic analysis of cAMP signaling in olfactory signal transduction in <em>Drosophila larvae</em></p> <p>The mechanism of olfactory signal transduction in insects is currently under debate. In <em>Drosophila melanogaster</em> larvae, olfactory signal transduction depends on the coexpression of a specific receptor and the non-specific Or83b coreceptor (Orco). Recent studies suggested the generation of a receptor potential via a second messenger independent pathway <sup>[1]</sup>. In another model the involvement of the second messenger cAMP is proposed. Here, Orco forms a cAMP gated channel<sup>[2]</sup>. We have tested this model in <em>Drosophila</em> larvae. <em>Drosophila</em> larvae express Orco in all of their 21 olfactory sensory neurons and show a robust positive chemotaxis to a variety of odors. Using the Gal4/UAS System we expressed the blue light sensitive adenylate cyclase Pac± <sup>[3]</sup> in olfactory sensory neurons. This enables us to increase cAMP levels in olfactory sensory neurons through light stimulation. As has been shown previously<sup>[4]</sup>, we observed that a positive chemotaxis towards odors can be mimicked by light stimulation. To determine the role of Orco in <em>Drosophila</em> olfactory transduction we used Pac± to raise the cAMP level in olfactory neurons of larvae which lack Orco. Our data show that in absence of endogenous Orco, the light-induced behavioral attraction response is largely abolished. To control for the proper functioning of the neurons, we activated larval olfactory neurons using channelrhodopsin 2. We observed light-induced positive taxis behavior with or without Orco. The data indicate that cAMP is involved in <em>Drosophila</em> olfactory signaling and that Orco is a target of cAMP. We use live imaging to visualize odor-induced and light-induced activity of larval olfactory neurons and we investigate possible functional implications of cAMP within the larval olfactory signal transduction system. First results will be presented.<br> <br> [1] Sato et al., 2008. Insect olfactory receptors are heteromeric ligand-gated ion channels. Nature 452(7190):1002-6. [2] Wicher et al., 2008. <em>Drosophila</em> odorant receptors are both ligand-gated and cyclic-nucleotide-activated cation channels. Nature 452:1007 1011. [3] Schroeder-Lang et al., 2007. Fast manipulation of cellular cAMP level by light in vivo. Nat Methods 1:39 42. [4] Bellmann et al., 2010. Optogenetically induced olfactory stimulation in <em>Drosophila</em> larvae reveals the neuronal basis of odor-aversion behavior. Front Behav Neurosci 2:4-27.<hr> <p class="style16">12<br> <br>Alex Gomez-Marin, Greg J. Stephens and Matthieu Louis </p> <p>Sensory Systems and Behaviour, Systems Biology, CRG  Centre for Genomic Regulation, Dr Aiguader 88, 08003 Barcelona, Spain<br> <br><a href="mailto:agomezmarin@gmail.com "> agomezmarin@gmail.com </a> </p> <p class="style17">Decision-Making in Larvae: Fruit Fly Navigation in Odor Gradients</p> <p>Using the olfactory system of the fruit fly as a model organism, we are searching for principles of sensory computation controlling navigation and decision-making. Previous work has shown that inputs from bilateral olfactory organs are not necessary for <em>Drosophila</em> larvae to chemotax, hence suggesting that decision-making relies upon temporal active sampling. Here we investigate this hypothesis tracking larval behavior at high-resolution and reconstructing its odor experience during navigation. We show that negative gradients integrated over time during runs trigger turns. Positive gradients generated by fast high-amplitude head casts accurately determine the steering direction, in a mechanism analogous to sniffing in vertebrates. Genetic modifications of the peripheral neural circuit reveal that orientation adapts to losses and gains of olfactory input. Our results suggest that larval chemotaxis represents an intermediate navigation strategy between the improved random walks of bacteria and the stereo-olfaction observed in vertebrates. <hr> <p class="style16">13<br> <br>Ayako Wada-Katsumata, Jules Silverman and Coby Schal</p> <p>Department of Entomology and W.M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, NC 27695, USA<br> <br><a href="mailto:akatsum@ncsu.edu">akatsum@ncsu.edu</a> </p> <p class="style17">Hate It or Love It: Differential inputs from gustatory neurons mediate feeding response to glucose in wild-type and glucose-averse German cockroaches, <em>Blattella germanica</em></p> <p>Glucose is a universal phagostimulant in many animal species, including cockroaches. However, some populations of the German cockroach are behaviorally deterred from eating glucose. It is thought that the  glucose-averse (GA) trait has evolved in response to toxic baits containing glucose. Although the GA cockroaches incur significant fitness costs in normal foraging on insecticide-free foods, this trait may confer greater survivorship under the strong selection pressure of bait-based pest control. To understand the mechanisms that underlie glucose aversion, we characterized the electrophysiological responses of gustatory neurons involved in glucose reception. Glucose and fructose elicited neural responses from the sugar receptor neuron in gustatory sensilla on the paraglossae of wild-type cockroaches (WT), while caffeine elicited responses from the bitter receptor neuron. On the other hand, while fructose also elicited responses from the sugar receptor neuron in the GA cockroach strain, glucose elicited responses from both the sugar and bitter receptor neurons. Our results suggest that the GA cockroaches may express a glucose reception system(s) on the bitter receptor neurons of the paraglossae. We also tested the effect of the glucose-averse trait on foraging behavior. In two-choice feeding assays, the GA cockroaches consumed fructose but not glucose or caffeine, while WT cockroaches accepted fructose and glucose but not caffeine. In olfactory associative leaning assays, the GA cockroaches associated innately preferred odors with glucose as a deterrent, and later avoided this odor while foraging. The WT cockroaches associated food odors with glucose as reinforcement, and later were attracted to this odor while foraging. The results indicate that the glucose-averse trait influenced not only ad-hoc food choices but also olfactory learning and foraging optimization. Generally, feeding behavior is elicited through activation of sugar receptor neurons in animals, whereas the activation of bitter receptor neurons suppresses feeding behavior and evokes aversive behaviors. Our results indicate that different sensory inputs in glucose reception result in opposite foraging behaviors in WT and GA cockroaches. <hr> <p class="style16">14<br> <br>Claudia Groh<sup>1</sup>, Ian A. Meinertzhagen<sup>2</sup> and Wolfgang Rössler<sup>1</sup></p> <p>1 University of Würzburg, Biozentrum, Zoologie II, Am Hubland, D-97074 Würzburg<br> 2 Dalhousie University, Life Sciences Centre, Halifax, NS, Canada<br><a href="mailto:claudia.groh@biozentrum.uni-wuerzburg.de"> claudia.groh@biozentrum.uni-wuerzburg.de </a> </p> <p class="style17">Synaptic microcircuits underlying olfactory processing: characterization and plasticity of mushroom-body calyx synapses in the honeybee</p> <p>The mushroom bodies (MBs) in the insect brain are important for olfactory processing including learning and memory. Their main input regions are the MB calyces. Honeybees possess large and doubled MB calyces divided into three anatomically distinct sensory input regions. In this study we focused on structural plasticity of input synapses (microglomeruli, MG) in the olfactory lip region of the MB calyx. Within the lip, medial (m) and lateral (l) antennal lobe tract (ALT) projection neurons (PNs) have different target regions. We investigated adult plasticity associated with sensory experience and age in both the m and l ALT region. To analyze changes in the organization of olfactory MG, presynaptic boutons of projection neurons (PNs) and dendritic compartments of MB intrinsic neurons, the Kenyon cells (KCs), were labeled using markers for synaptic proteins and cytosceletal elements. During natural transition from nurse bees to foragers the most drastic effect was a massive outgrowth of KC dendrites accompanied by presynaptic pruning of PN boutons. To investigate associated subcellular changes at the pre- and postsynaptic site of calycal MG, we employed serial-electron microscopy and 3D analyses. The results revealed novel features of MG at the level of synaptic sites and their connectivity. In general, the investigated changes were similar for both the m and l ALT projections in the MB-calyx lip: olfactory PN boutons showed a significant increase in surface area between nurse bees and foragers. Both types of PN boutons formed ribbon and non-ribbon synapses, and the overall numbers of active zones per PN bouton remained more or less constant. At the postsynaptic site, however, the number of postsynaptic profiles  formed primarily by KC dendrites, but also by extrinsic neurons  significantly increased per active zone. Ribbon as well as non-ribbon synapses formed mainly dyads in nurse bees and dyads, triads and tetrads in foragers. We conclude that outgrowing KC dendrites form increasing contacts with different PN boutons resulting in massive changes in the divergence/convergence ratios between individual PNs and KCs. These changes are likely to be driven by sensory activity and experience such as associative learning. The reorganization of olfactory synaptic microcircuits is likely to play an important role in task dependent changes in sensory processing and association.<br> Supported by HFSP, DFG SPP 1392 and NSERC DIS 0000065.<hr> <p class="style16">15<br>Wolfgang Rössler, Christina Scholl & Thomas S. Muenz</p> <p>University of Würzburg, Biozentrum, Zoologie II, Am Hubland, D-97074 Würzburg<br> <br><a href="mailto:roessler@biozentrum.uni-wuerzburg.de">roessler@biozentrum.uni-wuerzburg.de</a> </p> <p class="style17">Olfactory plasticity in the honeybee: molecular mechanisms of synaptic reorganization in the mushroom-bodies</p> <p>Olfactory projection neurons (PNs) from the antennal lobe synapse on Kenyon cell (KC) dendrites in distinct olfactory input regions of the mushroom bodies (MBs), brain centers involved in sensory association, learning and memory. Previous studies have shown that these synaptic complexes (microglomeruli, MG) express a high degree of plasticity. Synaptic reorganization (PN synaptic pruning and KC dendritic growth) can be induced by environmental factors during postembryonic caste determination (Groh et al. 2006, Brain Behavior & Evol), sensory experience during adult maturation and transition from nursing to foraging (Muenz et al. 2008 FENS abstracts), and the formation of stable long-term memory (Hourcade et al. 2010, J Neurosci). We began to investigate molecular mechanisms involved in this remarkable reorganization of olfactory synaptic microcircuits in the honeybee MB calyx by focusing on selected pre- and postsynaptic proteins: synapsin, a phosphoprotein known to be involved in plasticity of presynaptic vesicle release, calcium-calmodulin dependent protein kinase II (CaMKII) which was shown to form a  molecular memory via calcium activation and autophosphorylation, and f-actin, a cytoskeletal protein known to be important in dendritic spine motility. Our results show that synapsin is prominent in PN presynaptic boutons of olfactory projections in the lip, collar and basal ring of the MB calyx. F-actin was found highly enriched in KC dendritic spines, whereas tubulin was concentrated in dendritic shafts. Most importantly, activated (phopshorylated) pCaMKII was found at high concentrations in the dendritic compartments of a specific subpopulation of spiny KCs (non-compact class I KCs) with abundant arborizations in the lip and collar of the MB calyx. Within individual MG, pCaMKII was colocalized with f-actin in KC dendritic spines. pCaMKII expression was found throughout adult maturation and in forager bees indicating that it may be important for postsynaptic (dendritic) KC plasticity at all stages of adult life. We propose that CaMKII may provide an important link between sensory (olfactory) induced calcium activation and KC dendritic plasticity in MG synapses via direct interaction with the f-actin cytoskeleton and/or activation of gene transcription. <br>Supported by HFSP and DFG SPP 1392.<hr> <p class="style16">16<br> <br>Martin F. Brill<sup>1</sup>, Isabelle Reus<sup>1</sup>, Tobias Rosenbaum<sup>1</sup>, Christoph J. Kleineidam<sup>2</sup> & Wolfgang Rössler<sup>1</sup></p> <p>1 University of Würzburg, Biozentrum, Zoology II, Am Hubland, 97074 Würzburg, Germany<br> 2 University of Konstanz, Universitätsstraße 10, 78457 Konstanz, Germany<br> <br><a href="mailto:martin.brill@biozentrum.uni-wuerzburg.de">martin.brill@biozentrum.uni-wuerzburg.de</a></p> <p class="style17">Parallel processing in the honeybee olfactory pathway</p> <p> Honeybees possess a highly evolved olfactory system that allows them to detect and remember floral odors, to orient in the environment, and to communicate using pheromonal odors for species-specific social interactions. Odor information from olfactory receptor neurons (ORNs) on the insect antennae is projected to glomeruli in the antennal lobe (AL) and processed by local interneurons (LNs) in a spatio-temporal manner. From the AL glomeruli, olfactory information is transferred via two separate uniglomerular projection neuron (PN) output-tracts, the medial and the lateral antennal lobe tracts (m- and l-ALT) to higher-order brain centers, the mushroom bodies (MB) and the lateral horn (LH). This dual olfactory pathway is a unique feature in Hymenoptera (Kirschner et al. 2006, J Comp Neurol 499:933; Rössler and Zube 2011 ASD; Galizia and Rössler, 2010 Ann Rev Entomol 55:399). It is assumed that these parallel output tracts convey different aspects, such as quality, intensity or temporal structure of an olfactory stimulus.<br> Using multiple wire electrodes (adapted from Okada et al. 2007, J Neurosci 27:11736) and a customized multi-unit recording setup, we simultaneously recorded from multiple PNs in both ALTs. For visualization of the exact position of the electrodes, we made 3D-reconstructions of the recording sites based on a newly developed double staining method.<br> Dual recordings from 15 bees (65 units each tract) revealed that PNs from both tracts respond to the same set of general odors, pheromones and behavioral relevant odors from the bees natural environment. PNs recorded from the l-ALT showed faster (30ms averaged over all odors) and stronger (59%) odor responses with higher PN recruitment (54%) suggesting less accurate odor-quality coding. In contrast, the m-ALT showed slower and weaker (41%) odor responses with smaller PN recruitment (32%) but more complex firing patterns suggesting more elaborated odor-identity coding along the m-ALT. Temporal analyses show that the dual olfactory PN pathway may serve coincidence coding at the level of Kenyon Cells (KC). Cross correlation analyses from individual PN pairs revealed coincident activity of l- and m-PNs in a time range relevant for coincident activation of KCs.<br> In summary, our results support parallel processing of different features from similar odors via two central olfactory pathways (l- & m-ALT) to the MBs and LH. <br> Supported by DFG SPP 1392 and SFB 554 (A8).<hr> <p class="style16">17<br> <br>Yoichi Seki, Jürgen Rybak, Dieter Wicher, Silke Sachse and Bill S. Hansson</p> <p>Max Planck Institute for Chemical Ecology, Department of Evolutionary Neuroethology, 07745 Jena, Germany<br> <br><a href="mailto:yseki@ice.mpg.de"> yseki@ice.mpg.de</a></p> <p class="style17">Maps of Olfactory Representation from the Antennal Lobe to Higher Brain Centers in <em>Drosophila</em></p> <p><em>Drosophila melanogaster</em></p> is an excellent model system to understand the neural basis of olfaction. However, compared to a rather detailed understanding of the peripheral sensory system, olfactory processing mechanisms in the central nervous system are not yet fully understood. In order to analyze how odor information is represented in the antennal lobe (AL) and in higher brain centers, we mapped odor response profile and morphology of single projection neurons (PNs) in the <em>Drosophila</em> AL. We used <em>in vivo</em> whole-cell patch-clamp recordings and stimulated the antenna with 17 behaviorally relevant odors that elicit innate attraction or aversion in flies. These odor response profiles were compared with those of olfactory sensory neurons innervating the same glomeruli. Glomerular innervation patterns in the AL and axonal projecting patterns in the mushroom body and lateral horn were reconstructed for each PN and compared to its odor response pattern. This work provides insights into how odor information is transformed from sensory neurons to PNs leading to a neural representation in higher brain centers. It also provides a base to understand the importance of these odor representations for fly innate behavior.<p> This project was supported by the Max Planck Society<hr> <p class="style16">18<br> <br>Nobuaki Tanaka<sup>1,2</sup> and Aki Ejima<sup>2</sup></p> <p>1 PRESTO, Japan Science and Technology Agency, 4-1-8 Honcho Kawaguchi, Saitama 332-0012, Japan<br> 2 Career Path Promotion Unit for Young Life Scientists, Kyoto University, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan<br> <br><a href="mailto:nktanaka@cp.kyoto-u.ac.jp"> nktanaka@cp.kyoto-u.ac.jp</a></p> <p class="style17">Multiple antennal lobe-protocerebral tracts in <em>Drosophila</em></p> <p>The <em>Drosophila</em> antennal lobe consists of 54 glomeruli, each of which receives sensory input from a distinct type of either olfactory receptor neurons or other sensory neurons. The sensory information is first processed by antennal lobe-associated neurons, and then transferred to multiple secondary olfactory sites such as mushroom body and lateral horn via multiple antennal lobe-protocerebral tracts (APTs). It has been shown that the projection neurons of each APT have a distinct odor response pattern in honeybee, however, the odor responses to the same odor have not been compared between neurons originating from the same glomerulus but innervating various APTs.<br> The <em>Drosophila</em> pheromonal system is a good model to study the functional differences among each tract of projection neurons. Four glomeruli are known to respond to fly smell/sex pheromone: DA1, DL3, VA1d and VA1v. These glomeruli are innervated by peculiar types of projection neurons sending output through multiple APTs passing through one of multiple APTs. We here report the comparison of odor response patterns between neurons arborizing in the DA1 glomerulus, but innervating either the medial or mediolateral APT, and discuss how the lateral horn receives input from both tracts of projection neurons.<hr> <p class="style16">19<br> <br>Charles Chappuis, Caroline Joris and Patrick Guerin</p> <p>Institute of Biology, University of Neuchâtel, CH-2000 Neuchâtel, Switzerland<br> <br><a href="mailto:charles.chappuis@unine.ch"> charles.chappuis@unine.ch</a></p> <p class="style17">Response of the tsetse fly Glossina pallidipes to human breath and a visual target in a wind tunnel.</p> <p>Despite tremendous investments to control tsetse flies their disastrous consequences for human population prosperity through their capability to transmit African trypanosomes remains unacceptable. Experiments with tsetse flies in wind tunnels could provide important information on the host seeking behaviours of tsetse vectors of disease to improve trapping methods in the field. Quantifying spatio-temporal parameters of flight in tsetse flies in a wind tunnel is technically challenging due to their high speed of flight (up to 9 m" s<sup>-1</sup>), their sensitivity to lighting conditions and, like all flying insects, their capacity to exploit three-dimensional space. To improve the spatio-temporal resolution of the experimental design, we introduced a phtalogen blue sphere as a strong visual cue in the wind tunnel. This visual target induces local search behaviour by tsetse flies. Using a 3D tracking system we quantified the local search behaviour of tsetse around the blue sphere in the presence of kairomones, hypothesising that the more an odour is attractive the more tsetse are motivated to search for it. To test this hypothesis we used two types of odour cues, CO<sub>2</sub> as a single compound known to activate and attract tsetse flies and human breath as a complex blend of host-derived kairomones. We show that host odours are needed to induce flights toward the target and that the local search behavior around the sphere is more intense with biologically complex sources of kairomones compared to CO<sub>2</sub> in terms of time spent flying and the flight intensity around the visual target. Our gas chromatography linked tsetse fly antennogram analysis of human breath indicates this substrate contains important kairomones for tsetse flies other than CO<sub>2</sub>.<hr> <p class="style16">20<br> <br>Cornelia Bühlmann, Markus Knaden and Bill S. Hansson</p> <p>Max Planck Institute for Chemical Ecology, Department of Evolutionary Neuroethology, Hans-Knöll-Strasse 8, D-07745 Jena, Germany<br> <br><a href="mailto:cbuehlmann@ice.mpg.de"> cbuehlmann@ice.mpg.de</a></p> <p class="style17">Following the nest odour: Upwind plume following in desert ants</p> <p>By using path integration on their far reaching foraging runs desert ants <em>Cataglyphis fortis</em> are always informed about their position relative to the nest. In addition to path integration, the ants use visual and olfactory landmarks. Here we show that the nest itself releases an odour plume that can be used by the ants to pinpoint the nest entrance. This odour plume is not nest specific. We identified CO<sub>2</sub> as one component of the nest odour that alone is sufficient to provoke plume following. Furthermore we provide evidence that the ants respond to a nest plume only, when the path integrator tells them to be close to home. This strategy circumvents that the ants by mistake follow plumes of foreign nests and become killed inside.<p> This project was supported by the Max Planck Society.<hr> <p class="style16">21<br> <br>Takeshi Sakurai<sup>1</sup>, Hidefumi Mitsuno<sup>1</sup>, Stephan Shuichi Haupt<sup>1</sup>, Takeshi Fujii<sup>2</sup>, Masashi Tabuchi<sup>1</sup>, Keiro Uchino<sup>3</sup>, Yukio Ishikawa<sup>2</sup>, Hideki Sezutsu<sup>3</sup>, Ryohei Kanzaki<sup>1</sup></p> <p>1 Research Center for Advanced Science and Technology, The University of Tokyo, Tokyo 153-8904, Japan<br> 2 Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo 113-8657, Japan<br> 3 Transgenic Silkworm Research Unit, National Institute of Agrobiological Sciences, Ibaraki 305-8634, Japan<br> <br><a href="mailto:sakurai@brain.imi.i.u-tokyo.ac.jp"> sakurai@brain.imi.i.u-tokyo.ac.jp</a> </p> <p class="style17">Detection of a <em>Drosophila</em> pheromone by male silkmoths expressing a Drosophila pheromone receptor</p> <p>In moths and fruit flies, pheromones are detected by sensilla trichodea on the antennae. The sensillum lymph of these sensilla contains a high concentration of pheromone binding proteins (PBP), which increase the capture of hydrophobic pheromone molecules into the lymph and transfer them to pheromone receptor proteins expressed on the dendritic membrane of pheromone receptor neurons. Recent studies using the fruit fly Drosophila melanogaster have shown that a PBP, named LUSH, is essential for the detection of pheromone of that species, 11-cis-vaccenyl acetate (cVA), and suggested that a pheromone-PBP complex interacts with the pheromone receptor protein Or67d. To clarify the contribution of LUSH to the detection of cVA by Or67d, we utilized the sex pheromone detection system of the silkmoth <em>Bombyx mori</em> in which activation of receptor neurons tuned to bombykol, the major sex pheromone component of the silkmoth, is sufficient to trigger characteristic pheromone orientation behavior. Using the GAL4/UAS system, we generated a transgenic silkmoth that is designed to express Or67d under the control of a putative promoter sequence of the bombykol receptor gene BmOR1. Expression analysis of BmOR1-GAL4/UAS-Or67d moths revealed that Or67d is expressed in bombykol receptor neurons. The expression of Or67d does not affect projection patterns of bombykol receptor neurons in the antennal lobe. Male moths expressing Or67d exhibited the typical pheromone searching behavior in response to cVA, but not to the structurally similar chemicals 11-cis-vaccenyl alcohol and 11-cis-vaccenyl aldehyde, indicating that Or67d expressed in bombykol receptor neurons conferred the ability to respond to cVA even in the absence of LUSH. These results imply that the specific combination of LUSH and cVA is not essential for activation of Or67d.<hr> <p class="style16">22<br> <br>William B. Walker III<sup>1</sup>, Anne-Emmanuelle Felix<sup>1</sup>, Christelle Monsempes<sup>2</sup>, Nicolas Montagné<sup>3</sup>, Rickard Ignell<sup>1</sup>, Mattias Larsson<sup>1</sup>, Emmanuelle Jacquin-Joly<sup>2</sup></p> <p>1 - Department of Plant Protection Biology, Division of Chemical Ecology, Swedish University of Agricultural Sciences, Alnarp, Sweden.<br> 2 - Physiology of Insect Signaling and Communication (UMR PISC), National Institute of Agricultural Research (INRA), Versailles, France.<br> 3 - Physiology of Insect Signaling and Communication (UMR PISC), Université Paris 6, 7 quai Saint-Bernard, Paris, France.<br> <br><a href="mailto:william.b.walker.iii@slu.se"> william.b.walker.iii@slu.se</a></p> <p class="style17">Molecular Mechanisms of Olfactory Sensation in <em>Spodoptera littoralis</em>: Deorphanization of the Odorant Receptors and their Role in Host Plant Choice Behaviour</p> <p>The olfactory sense is a critical determinant of vital insect behaviours, including mate and food seeking, oviposition and predator avoidance. The chemical ecology research group at the Swedish Agricultural University in Alnarp and the PISC group at the French Institute for Agricultural research in Versailles, have established the noctuid moth, <em>Spodoptera littoralis</em> (the Egyptian Cotton Leafworm) as a model for investigation of noctuid olfaction and chemical ecology. At the molecular level, the fundamental unit mediating the insects interaction with its olfactory environment is the odorant receptor protein, which is functionally expressed in odorant receptor neurons within olfactory appendages, primarily the insect antennae. <br> One primary research focus has been on characterization of the odorant receptor genes, which we recently identified in this species. We have investigated a functional role for individual receptors in modulating important vital behaviours via quantitative real time PCR analyses of odorant receptor expression levels under varying physiological conditions deemed to be behaviourally relevant. Additionally we are seeking to determine the receptive range of each odorant receptor via deorphanisation experiments in a heterologous expression system. Individual olfactory receptor proteins are currently being expressed in the model Empty Neuron system of the fruit fly <em>Drosophila melanogaster</em>, to characterize their response profiles by means of single neuron electrophysiological recordings. Collectively, these results represent an important step in understanding the molecular determinants underlying the mechanisms of olfactory mediated behaviour in <em>S. littoralis</em>.<hr> <p class="style16">23 <br> <br>Teiichi Tanimura, Naoko Toshima and Yusuke Homori</p> <p>Department of Biology, Graduate School of Sciences, Kyushu University, Hakozaki, Fukuoka, 812-8581 Japan<br> <br><a href="mailto:tanimura@kyudai.jp"> tanimura@kyudai.jp</a></p> <p class="style17">Feeding responses to amino acids and the nutritional requirement in <em>Drosophila</em>.</p> <p>Insects have to ingest nutrients to maintain their lives for growth and propagation. Gustation is a sensory function to discriminate between nutrients and harmful substances in the environment. We recently revealed that internal nutrient sensing is also important for food searching in <em>Drosophila melanogaster</em> (Fujita and Tanimura, Curr. Biol. 21, 751-755, 2011). Amino acids containing in yeast is necessary for egg-production and longevity in <em>Drosophila</em>. We studied if <em>Drosophila</em> senses amino acids by the two-choice preference test and the cafe assay. We showed that Drosophila prefers amino acids to water and sugar at low concentration, indicating that <em>Drosophila</em> can sense amino acids. However, electrophysiological recordings from three types of labellar chemosensilla failed to record nerve responses to amino acids. We found that mated female flies reared in medium without yeast ingest significantly larger amount of amino acids than mated female flies reared under normal medium containing yeast. Thus <em>Drosophila</em> can sense amino acids by unidentified receptors and should have an internal mechanism to increase amino acids intake when flies need amino acids.<br>Supported by grants from the by the Grant-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology, Japan.<hr> <p class="style16">24<br> <br>Sarah Koch<sup>1</sup> , Bill S. Hansson<sup>2</sup>, Christoph J. Kleineidam<sup>1</sup>, Ewald Grosse-Wilde<sup>2</sup></p> <p>1 University of Konstanz, Department of Biology, Universitätsstraße 10, 78464 Konstanz, Germany<br> 2 Max Planck Institute for Chemical Ecology, Beutenberg Campus, Hans-Knöll Straße 8, 07745 Jena, Germany<br> <br><a href="mailto:grosse-wilde@ice.mpg.de"> grosse-wilde@ice.mpg.de</a></p> <p class="style17">Putative antennal Pheromone receptors across leaf cutter ant castes.</p> <p>Leaf-cutting ants live in highly organized colonies with a single queen and several million workers. Division of labor within the worker caste is based on task allocation of workers that differ in size (alloethism). Chemosensation plays an important role in the self organization of the social structure as well as for specific tasks. Pheromones are for example used to locate mating partners, or to lay trails to enable other individuals to faster locate resources. In the leaf-cutting ant <em>Atta vollenweideri</em>, 5 distinct phenotypes are described (queens, males, and three worker phenotypes) based on body size and neuroanatomy of the first olfactory neuropil, the antennal lobe (AL). All 5 phenotypes differ in number (240-440) and size of glomeruli. In large workers one glomerulus and in males three glomeruli are extremely large (macroglomeruli; MG). The different morphological AL phenotypes are the neuronal basis for distinct behavioral patterns and division of labor. As an example, the MG in workers processes information about the trail pheromone and workers with MG are more sensitive to the pheromone. The males macroglomeruli are supposed to process the information of the queen-specific sex pheromone to locate potential mating partners.<br> <p>In all described species the number of glomeruli in the AL is correlated to the expressed ORs and IRs in the respective chemosenroy organs, with populations innervating specific glomeruli based on the identity of their respecitve receptor. Therefore, we assume that the AL polymorhpisms are reflected in the expression pattern of receptor coding genes in the antenna. We analysed the totality of antennally expressed genes across castes (the antennal transcriptome) by random next-generation sequencing. From this data we identified 194 putative OR coding genes. Subsequently, we performed caste-specific microarrays to reveal the phenotypical polymorphism on a receptor level and to find pheromone receptor candidates based on the expression patterns in the different castes and subcastes.<hr> <p class="style16">25 <br> <br>Hans Ragnar Norli and Geir Kjølberg Knudsen</p> <p> Bioforsk Plant Health and Plant Protection, Høgskoleveien 7, N-1432 Ås, Norway<br> <br><a href="mailto:hansragnar.norli@bioforsk.no"> hansragnar.norli@bioforsk.no</a></p> <p class="style17">GC-MS screening of plant volatiles in extracts from dynamic headspace collection by use of Automatic Masspectral Deconvolution and Identification Software (AMDIS).</p> <p>Manual interpretation of chromatograms from dynamic headspace collection of plant volatiles are known to be time consuming. Most GC-MS software s allow the user to check peaks manually or by an automatic procedure resulting in a report containing suggestions with match factors and names. Both procedures may give unnecessarily false positive or false negative identifications because no deconvolution of the chemical background is involved. Automatic Masspectral Deconvolution and Identification Software (AMDIS) from NIST is a powerful deconvolution software which identifies ion traces that maximize simultaneously to fit a model of a chromatographic peak. The component spectrum is compared with spectra in a database and reported only if the quality match factor is over a certain preset value. In addition to deconvolution AMDIS has several possibilities that can be included in screening of volatile compounds:<br> <p>1. Customer can build their own databases of target compounds by either injecting reference substances or importing spectra from NIST database.<br> 2. Target compounds can be connected to fixed retention times or retention indexes. Using Retention indexes instead of retention times is more powerful because retention indexes can be found in the literature and are only dependent of the stationary phase.<br> 3. The software can be used to make databases of samples containing peak areas of target compounds suitable for multivariate statistics (PCA).<br> 4. AMDIS can be included in the Deconvolution Reporting Software (DRS) from Agilent Technologies. The DRS produces a report which contain target cas #, names, amount (if calibrated), retention time, AMDIS match, deviation in retention index and NIST reverse match.<hr> <p class="style16">26 <br> <br>Masashi Tabuchi<sup>1, 3</sup>, Li Dong<sup>2</sup>, Shigehiro Namiki<sup>3</sup>, Takeshi Sakurai<sup>3</sup>, Kei Nakatani<sup>2</sup>, and Ryohei Kanzaki<sup>1, 3</sup></p> <p> 1 Department of Advanced Interdisciplinary Studies, Graduate School of Engineering, The University of Tokyo, Japan. <br> 2 Graduate School of Life and Environmental Sciences, University of Tsukuba, Japan. <br> 3 Research Center for Advanced Science and Technology, The University of Tokyo, Japan.<br> <br> <a href="mailto:tabuchi@brain.imi.i.u-tokyo.ac.jp"> tabuchi@brain.imi.i.u-tokyo.ac.jp</a></p> <p class="style17">Two distinct types of local interneurons exhibit different synaptic connectivity in the silkmoth antennal lobe</p> <p> Neurons in silkmoth antennal lobe (AL) are investigated well in their morphology and odor-evoked firing activity. However, their intrinsic electrical properties including voltage-gated ionic currents and synaptic connectivity were not known. To address this, whole-cell current- and voltage-clamp recordings were made from two types of morphologically identical local interneurons (LNs) and second-order projection neurons (PNs) in silkmoth AL. We first found that the two morphological types of LNs exhibited distinct physiological properties. One morphological type of LNs showed spiking response (with voltage-gated sodium current and gene expression), whereas the other type of LNs was nonspiking (without voltage-gated sodium current and gene expression). Although the voltage-gated potassium currents was similar in both LNs types, functional parameters of their voltage-gated calcium currents were significantly distinctive between the two LNs types. To describe their synaptic connectivity, we next performed dual whole-cell recording. In the pairs of same type of spiking LNs, synaptic transmission via both chemical and electrical coupling was observed with membrane potential synchrony. On the other hand, synaptic connectivity between spiking and nonspiking types of LNs was not detectable. Synaptic connection with PN was also distinctive feature between these two LNs types. Thus, our results indicate that there are two distinct types of LNs in silkmoth AL, and their synaptic connectivity was substantially different form. We propose the distinct functional roles of these two distinct types of LNs to shape odor-evoked firing activity in AL network. <hr> <p class="style16">27 <br> <br>Chertemps T.<sup>1</sup>, Durand N.<sup>1</sup>, Carot-Sans G.<sup>2</sup>, Bozzolan F.<sup>1</sup>, Debernard S.<sup>1</sup>, Rosell-Pellise G.<sup>2</sup> and Maïbèche-Coisne M.<sup>1</sup> </p> <p>1 UMR_A 1272 Université Paris 6-INRA « Physiologie de l Insecte : Signalisation et Communication », Paris-Versailles, France.<br> 2 Department of Biological Organic Chemistry, IIQAB (CSIC), Barcelona, Spain.<br> <br><a href="mailto:Thomas.chertemps@upmc.fr"> Thomas.chertemps@upmc.fr</a></p> <p class="style17"><em>In vitro</em> characterization of two antennal Odorant-Degrading Enzymes in the noctuid moth <em>Spodoptera littoralis</em></p> <p>Most of the molecular actors involved in olfactory processes in insects are now well documented at the peripheral level. If the steps of odorant transport by odorant-binding proteins (OBPs) and reception by olfactory receptors (ORs) had been described in great detail, the mechanisms of odorant inactivation are however still poorly understood. Several enzymes have been shown to degrade pheromones in insect antennae, suggesting that these Odorant-Degrading Enzymes (ODEs) could participate in odorant inactivation by removing active odorant molecules from the sensillum lymph. However, only a few number of enzyme families have been identified as containing ODEs candidates and few functional data are available on purified ODEs.<p>In the cotton leafworm <em>Spodoptera littoralis</em>, which uses a mix of acetates as sex pheromone, we have identified 20 antennal esterases thorough the analysis of a male antennal EST library (Durand, 2010). Among them, we have identified two ODE candidates, SlCXE7 and SlCXE10, overexpressed in the olfactory organs and associated with olfactory sensilla. Recombinant enzymes have been produced in vitro using the baculovirus expression system in order to test their catalytic properties. Interestingly, these two enzymes presented different substrate specificities towards the three odorants tested, i.e. two sex pheromone components (Z9E11-14:Ac and Z9E12-14:Ac) and a host plant volatile (Z3-6:Ac). SlCXE7 presented a similar affinity for the two pheromone components (Km ~ 45 µM) and was able to efficiently degrade them. Despite a lower affinity for the host plant component (Km ~ 1.5 mM), SlCXE7 was also able to rapidly hydrolyze it because of a higher Vmax. In comparison, SlCXE10 was only able to degrade the green leaf volatile (Durand, 2010). Moreover, pre-exposure of animals to these three odorants differentially increased the transcription of the corresponding genes, suggesting a possible regulation of expression by their substrates.<p>Our results suggest that ODE diversity could be associated with a functional specialization of the enzymes toward different odorant substrates.<p>Durand, N., G. Carot-Sans, T. Chertemps, N. Montagne, E. Jacquin-Joly, S. Debernard & M.Maibeche-Coisne (2010) A diversity of putative carboxylesterases are expressed in the antennae of the noctuid moth <em>Spodoptera littoralis</em>. Insect Mol Biol, 19, 87.<p>Durand N, Carot-Sans G, Chertemps T, Bozzolan F, Party V, Renou M, Debernard S, Rosell G, Maïbèche-Coisne M. (2010) Characterization of an antennal carboxylesterase from the pest moth <em>Spodoptera littoralis</em> degrading a host plant odorant. PLoS One, Nov 29;5(11):e15026.<p>Vogt RG (2005) Molecular basis of pheromone detection in insects. In: Comprehensive Insect Physiology, Biochemistry, Pharmacology and Molecular Biology (Gilbert L, Iatro K, Gill S, eds), pp 753-804. London: Elsevier.<hr> <p class="style16">28 <br> <br>Toru Maeda, Tetsutaro Hiraguchi, Mamiko Ozaki</p> <p>Grad. Sch. Sci., Kobe Univ., Kobe 657-8501, Japan<br> <br><a href="mailto:081s321s@stu.kobe-u.ac.jp"> 081s321s@stu.kobe-u.ac.jp</a></p> <p class="style17">Integration of olfactory and gustatory signs of food in <em>Phormia regina</em>: odor of 1-Octen-3-ol via maxillary palps enhances feeding behavior promoted by labellar sensillar stimulation by sugar.</p> <p>Olfaction and taste are closely related to feeding behavior and food preference in animals. In <em>Phormia regina</em> as a nectar-sucking insect, odor palatability is important in the distinction between food and poison. Fly has two olfactory systems, antennae (main olfactory organ) and maxillary palps (accessory olfactory organ). When their maxillary palps were missing, feeding behavior of <em>P. regina</em> would be changed by 1-Octen-3-ol odor that enhances feeding in the intact flies. Therefore, this odor, only via maxillary palps, was thought to enhance the fly appetite to sucrose.<p>We observed the distribution of olfactory sensilla on the maxillary palps, and found that the olfactory sensilla were densely distributed on the distal part. We cut off the sensilla in this part and introduced a fluorescent dye to stain their neuronal projections into the brain. Then, the projection was observed in the subesophargeal ganglion (SEG), the primary gustatory center of the fly. This was different from the case, in which whole the maxillary palps were cut. In this case, additional projections were seen in the antennal lobe, the primary olfactory center.<p>We also stained gustatory nerves of each labellar taste sensillum of 11 LL-type sensilla on a labellar lobe and showed their special projection patterns. Thus, we newly found that the spatial projection patterns of afferent nerves from the maxillary olfactory sensilla and those from the single labellar taste sensilla. appear neighboring each other in a same region of the SEG.<p>Our morphological results suggest that appetitive olfactory signs via maxillary palps and phagostimulative gustatory sign via labellar taste sensilla are possibly integrated in the SEG. <hr> <p class="style16">29 <br> <br>Mamiko Ozaki<sup>1</sup>, Hajime Shiotani<sup>1</sup>, Toru Maeda<sup>1</sup>, Tetsutaro Hiraguchi<sup>1</sup>, Saki TeraJÿima<sup>1</sup>, Takaniri Ida<sup>2</sup> and Masayasu Kojima<sup>3</sup></p> <p>1 Kobe University, Department of Biology, Faculty of Science, Nada, Kobe 657-8501, Japan<br> 2 Interdisciplinary Research Organization, University of Miyazaki, Miyazaki 889-1692, Japan<br> 3 Molecular Genetics, Institute of Life Science, Kurume University, Kurume, Fukuoka 839-0864,Japan<br><a href="mailto:mamiko@port.kobe-u.ac.jp"> mamiko@port.kobe-u.ac.jp</a></p> <p class="style17">Regulation of feeding by newly found neuropeptides in the fly. </p> <p>In humans and other mammalians, hormonal regulation of feeding has been well studied. Some peptide hormones and/or neuropeptides involved in feeding regulation have been reported also in insects. In the fly, feeding behavior triggered by phagostimulative tastes is initiated by excitation of the sugar receptor neurons. Then, the proboscis extension reflex (PER), which could be an indicator of feeding motivation, is exhibited. Once the fly starts feeding, food intake lasts until satiation. Recently, a neuropeptide, leucokinine was reported to regulate not starting but stopping feeding in <em>Drosophila melanogaster</em>. In the present paper, using newly found peptides of <em>Drosophila</em>, dRY-1 and dRY2, we tested their regulatory effects on the feeding behavior of the blowfly, <em>Phormia regina</em>. These peptides dissolved in the fly linger were injected into the thorax, and between before and after the injection, responsiveness of the sugar receptor cell, PER sensitivity, and sucrose intake were compared. dRY-1 but not dRY-2 depressed the responsiveness of the sugar receptor cell. Both peptides clearly decreased the PER sensitivity but not so clearly depressed sucrose intake. Thus, the results suggest that these peptides, which have a different role in the feeding regulation from leucokinine, mainly affect feeding motivation of the fly. Such a depressive effect on feeding motivation might be caused by decrease in the responsiveness of the sugar receptor neuron especially affected by dRY-1.<p> Supported by a grant of KAKENHI to MO.<hr> <p class="style16">30<br> <br>Nicolas Montagné<sup>1</sup>, Thomas Chertemps<sup>1</sup>, Isabelle Brigaud<sup>2,#</sup>, Adrien François<sup>1,2</sup>, Marie-Christine François<sup>2</sup>, Philippe Lucas<sup>2</sup>, Mattias Larsson<sup>3</sup>, Emmanuelle Jacquin-Joly<sup>2</sup></p> <p>1 UPMC  Université Paris 6, UMR-A 1272 Physiologie de l Insecte : Signalisation et Communication, 7 quai Saint-Bernard, F-75252, Paris cedex 05, France<br> 2 INRA, UMR-A 1272 Physiologie de l Insecte : Signalisation et Communication, Route de Saint-Cyr, F-78026, Versailles cedex, France<br> 3 Swedish University of Agricultural Sciences, Department of Plant Protection Biology, PO Box 44, SE-230 53 Alnarp, Sweden<br> # Present address: CNRS  Université Claude Bernard Lyon 1, Centre de Génétique et de Physiologie Moléculaire et Cellulaire, F-69622 Villeurbanne cedex, France<br> <br><a href="mailto:nicolas.montagne@snv.jussieu.fr"> nicolas.montagne@snv.jussieu.fr</a></p> <p class="style17">Functional characterization of a sex pheromone receptor in the pest moth Spodoptera littoralis by heterologous expression in <em>Drosophila</em></p> <p>Moth pheromone communication being a long-standing model for insect biology, numerous chemical, electrophysiological and behavioural studies have led to widespread knowledge on this subject throughout the twentieth century. However, only a few moth pheromone receptors have been identified and functionally characterized to date, using a diversity of approaches such as heterologous expression in xenopus oocytes, cell lines or <em>Drosophila</em> antennae. Taking advantage of an EST library prepared from the antennae of the noctuid moth <em>Spodoptera littoralis</em>, we have identified four putative pheromone receptors in this species. Here, we characterized one of these receptors, SlitOR6, by cloning its full length sequence, investigating its expression pattern by in situ hybridization and searching for S. littoralis pheromone ligands using <em>Drosophila</em> as a heterologous expression system. We revealed that SlitOR6 is the receptor for Z9,E12-14:OAc, a minor component of the sex-pheromone blend of <em>S. littoralis</em>. Responses to this compound appeared to be highly specific. Heterologous expression of a moth pheromone receptor in <em>Drosophila</em> antennae is thus well adapted for the de novo identification of ligand-PR couples. This approach appears as a keystone for developing further studies on the contribution of PRs to the response specificity of the moth pheromonal system. Moreover, since <em>S. littoralis</em> is an important crop pest in Africa and Southern Europe, functional characterization of its PRs could lead to new approaches in sexual behaviour disruption in a context of sustainable strategies in plant protection.<hr> <p class="style16">31 <br> <br>Erwan Poivet, Kacem Rharrabe, Nicolas Glaser, Christelle Monsempès, Marie-Christine François, Didier Rochat, Michel Renou, Frédéric Marion-Poll, Emmanuelle Jacquin-Joly. </p> <p>UMR INRA-UPMC PISC « Physiologie de l insecte : signalisation et communication », INRA, Route de Saint-Cyr, 78026 Versailles cedex, France.<br> <br><a href="mailto:erwan.poivet@versailles.inra.fr"> erwan.poivet@versailles.inra.fr</a></p> <p class="style17">Caterpillars care about sex pheromone.</p> <p>Lepidopteran larvae are a major source of global agricultural loss. Behavioural analyses have provided evidence that lepidopteran larvae are capable of odor discrimination and different volatile molecules from potential food sources have been shown to elicit specific olfactory attractive or repellent responses. Here, we discovered that the adult sex pheromone represents an unsuspected but relevant olfactory cue for larvae of a noctuid moth, the cotton leafworm <em>Spodoptera littoralis</em>. Supported by behavioural, electrophysiological and molecular data, we report here that S. littoralis larvae are able to detect and orient toward the adult sex pheromone. First, using a locomotion compensator, we evidenced that <em>S. littoralis</em> larvae walked to a sex pheromone source in a dose-dependant manner whereas a heterospecific sex pheromone did not elicit comparable behaviour. Second, this behaviour was not observed when antennae were covered with wax, revealing that antennae are necessary to detect the adult sex pheromone. More, by recording the responses of olfactory neurons located in the sensilla basiconica of the larval antenna (second segment), we showed that larvae antennae housed olfactory receptor neurons responding to this cue. Third, we demonstrated using RT-PCR and <em>in situ</em> hybridization that larval antennae expressed the three pheromone-binding protein genes previously identified in adults. Since these genes encode proteins supposed to play a role in pheromone detection by specific binding to pheromone components, their presence in larval antennae suggests that larvae possess the molecular machinery for pheromone detection. <p>Taken together, these surprising results ask the question of the biological significance of a sexual signal for an immature stage and several hypotheses will be discussed.<hr> <p class="style16">32 <br> <br>Emmanuelle Jacquin-Joly<sup>1</sup>, Nicolas Montagné<sup>2</sup>, Christelle Monsempes<sup>1</sup>, Erwan Poivet<sup>1</sup>, Violaine Olivier<sup>1</sup>, William B. Walker III<sup>3</sup>, Mattias Larsson<sup>3</sup>, Pavel Senin<sup>4</sup>, Fabrice Legeai<sup>4</sup>.</p> <p>1 INRA, UMR PISC, Route de Saint-Cyr, F-78026, Versailles cedex, France<br> 2 UPMC  Université Paris 6, UMR PISC, 7 quai Saint-Bernard, F-75252, Paris cedex 05, France<br> 3 Swedish University of Agricultural Sciences, Department of Plant Protection Biology, PO Box 44, SE-230 53 Alnarp, Sweden<br> 4 1IRISA, équipe Symbiose, Campus universitaire de Beaulieu, 35042 Rennes Cedex, France<br> <br><a href="mailto:emmanuelle.jacquin@versailles.inra.fr"> emmanuelle.jacquin@versailles.inra.fr</a></p> <p class="style17">Olfaction in the noctuid moth <em>Spodoptera littoralis</em>: identification of genes involved through a transcriptomic strategy</p> <p>Odor recognition relies on the expression of a diversity of olfactory genes involved in different steps within the insect antennae. With the aim at investigating this diversity, we developed a transcriptomic approach on both adult and larvae antennae in the noctuid moth <em>Spodoptera littoralis</em>. Both Sanger and next generation sequencing strategies (454) allowed us annotating more than 10 000 expressed genes. Among them, we described 40 candidate olfactory receptors (ORs), 12 olfactory ionotropic receptors (IRs), 2 sensory neurone membrane proteins (SNMP) and different families of odorant-binding proteins. Interestingly, we also identified putative gustatory receptors expressed in the antennae. This inventory creates the basis for investigating the contribution of these different gene families in the antennal olfactory process. RT-PCR and qPCR experiments revealed a differential expression of the OR set between sexes, between developmental stages, and, more surprisingly, along the length of the adult antennae. Among the ORs, 4 candidate pheromone receptors were identified whose functional characterization is in progress.<p>This study not only established the use of transcriptomic sequencing for the identification of OR-encoding genes in a species for which no genomic data are available, but also highlighted the presence in antennae of genes potentially involved in olfactory modulation, such as genes encoding biogenic amine and hormone receptors, takeout-like and JH-binding proteins, as well as circadian clock elements. <hr> <p class="style16">33<br> <br> Geir K. Knudsen, Marco Tasin and Hans Ragnar Norli</p> <p>Bioforsk Plant Health and Plant Protection, Høyskoleveien 7, N-1432 Ås, Norway<br> <br><a href="mailto:geir.knudsen@bioforsk.no"> geir.knudsen@bioforsk.no</a></p> <p class="style17">Pest control with kairomones in a host shifting moth</p> <p>Kairomones intersecting host searching females is an attractive method for species-specific pest control. Apple fruit moth, <em>Argyresthia conjugella</em>, is a major pest of apples in Fennoscandia. The severity of the attacks on apple happens as a response to large scale masting in the moths principal host rowan, <em>Sorbus aucuparia</em>. Co-occurrence of volatile compounds in rowan and apple is suggested to facilitate the forced host shift.<p> The apple fruit moth responds to odour from its principal host with upwind orientation in a wind tunnel. Host responding apple fruit moths have high plasticity to blend ratios suggesting why a specialist insect can locate alternative host during intermast years and damage apples. However, even with all host compounds present, distortions of blend ratios seriously jeopardize upwind orientation in laboratory bioassays.<p>In a combined approach with wind tunnel bioassays and field trapping, we have now identified a seven-component blend which is highly attractive for gravid female apple fruit moths. The new blend is especially attractive in apple crops, showing high odour competition compared to the secondary host. Verification of the blend in monitoring to achieve increased precision of pesticide sprays, establishment of economic damage thresholds and mass trapping is ongoing. <hr> <p class="style16">34<br> <br>Sharon R. Hill<sup>1</sup>, Satoshi Okawa<sup>2</sup> and Rickard Ignell<sup>1</sup></p> <p> 1 Division of Chemical Ecology, Department of Plant Protection Biology, Box 102, Swedish University of Agricultural Sciences, SE-23053 Alnarp, Sweden.<br> 2 EMBL Heidelberg, Meyerhofstraße 1, DE-69117 Heidelberg, Germany.<br> <br><a href="mailto:sharon.hill@slu.se"> sharon.hill@slu.se</a></p> <p class="style17">Mosquito taste: genes to behaviour</p> <p>When we think of the model insect, we tend to focus on <em>Drosophila</em> with its annotated genome and wide range of genetic tools. However, to study taste from genes to behaviour in the adult insect, the mosquito also provides a strong model. The life history of the mosquito separates food source from oviposition site, both spatially and temporally, since following a full blood meal mosquitoes cease feeding-related behaviours until oviposition is complete. Mosquitoes also make use of two distinct food sources, blood and sugar. This separation of resource use provides us with the option of studying gustatory-related behaviours in a variety of controlled physiological states. Combining this life history with the availability of annotated genomes and state-of-the-art experimental techniques, the mosquito represents a strong model for the study of gustation.<p>We investigated feeding-related decisions in <em>Aedes aegypti</em> (L.) by presenting adults with simple diets of paired gustatory stimuli conveying information concerning energy content, nutrient richness, osmotic balance and food toxicity in a two-diet matrix assay. We systematically characterized the diet selection behaviour of male and female <em>A. aegypti</em> for 27 putative feeding cues potentially involved in nectar/honeydew feeding (e.g. sugars, amino acids, salts or alkaloids).<p>The molecules that confer selectivity and sensitivity to contact chemoreceptive neurons in mosquitoes constitute a superfamily of seven-transmembrane domain proteins, and are known as gustatory receptors (Grs). This receptor superfamily is highly divergent (i.e. <20% amino acid similarity among all mosquito Grs). This high degree of divergence amongst chemoreceptors may be, in no small part, responsible for the range of mosquito feeding behaviours. While the ligands are predicted for a few mosquito Grs, for the majority of Grs the ligands are still unknown. On the way towards de-orphaning these Grs, we have now completed the tissue and sex expression profile of <em>A. aegypti</em> Grs.<p>Here we provide a solid foundation for future research into taste, not only in mosquitoes, but also in insects in general. Investigations into areas such as the molecular basis of gustatory behavioural plasticity in response to physiological state will be made possible. In mosquitoes, this research will also lead to expanded options for biological control of these highly dangerous disease vectors and aid researchers in accurately determining vectoral capacity. <hr> <p class="style16">35<br> <br>Masasuke Ryuda<sup>1</sup>, Teiichi Tanimura<sup>2</sup>, Frédéric Marion-Poll<sup>3</sup>, Hiroshi Yoshikawa<sup>1</sup> and Katsuhisa Ozaki<sup>1</sup></p> <p> 1 JT Biohistory Research Hall, Takatsuki Osaka, 569-1125 Japan,<br> 2 Department of Biology, Graduate School of Sciences, Kyushu University, Hakozaki, Fukuoka, 812-8581 Japan,<br> 3 INRA, UMR 1272 Physiologie de l'Insecte: Signalisation et Communication, F-78000 Versailles, France.<br> <br><a href="mailto:masasuke.ryuda@brh.co.jp"> masasuke.ryuda@brh.co.jp</a></p> <p class="style17">Electrophysiological characterization of tarsal gustatory receptor neurons responding to oviposition stimulants and other tastants in the swallowtail butterfly, <em>Papilio xuthus</em>.</p> <p>Host plant selection is important for oligophagous insects for both growth and reproduction. <em>Papilio xuthus</em>, generally called the swallowtail butterfly, feeds and lays eggs on the leaves of the <em>Rutaceae</em> family. Phytochemical compounds stimulating oviposition are the most important factor for oviposition behavior. Females perceive oviposition stimulants as tastants through their chemosensilla on the foreleg tarsomere by drumming the leaf surface to determine if a plant is suitable for larval feeding. Interestingly, these stimulants show no oviposition activity when assayed as single compounds, and they need to be presented as a mixture for eliciting the oviposition behavior.<p> Here we attempted to elucidate why these compounds need to be presented as a mixture, using electrophysiological observations and oviposition behavioral assays. In addition, we characterized the morphology of sensilla, determined the number of gustatory receptor neuron (GRN) housed in sensilla and evaluated the sensitivity of tarsal sensilla to general tastants.<p> Chemosensilla were classified into three types, L1, L2 and S according to their sizes and their electrophysiological responses to oviposition stimulants and general tastants. L1 sensilla responded to five oviposition stimulants among eight previously known as stimulants. These stimulants elicited three types of spike when they were used either separately or as a mixture, which corresponded to the number of GRNs predicted to respond to oviposition stimulants. Mixtures of stimulants eliciting all three spikes showed high oviposition induction in the assay of oviposition behavior. These results suggest the firing of all three spikes in the discrete GRNs housed into the L1 sensilla is essential for inducing oviposition behavior.<p> This work was supported by a joint JSPS-INRA grant under the Japan-France Research Cooperative Program (T.T. and F.M.P) and by a grant from the Ministry of Education, Culture, Sports and Technology of Japan to T.T.<hr> <p class="style16">36<br> <br>Federica Trona<sup>1,3</sup>, Gianfranco Anfora<sup>1</sup>, Anna Balkenius<sup>3</sup>, Alan Knight<sup>2</sup>, Marco Tasin<sup>1</sup>, Peter Witzgall<sup>3</sup> and Rickard Ignell<sup>3</sup></p> <p>1 IASMA Research and Innovation Center, Fondazione E. Mach, 38010 S. Michele a/A (TN), Italy<br> 2 Yakima Agricultural Research Laboratory, USDA, WA 98951, USA<br> 3 Chemical Ecology Group, SLU, Box 102, 23053 Alnarp, Sweden<br> <br><a href="mailto:federica.trona@iasma.it"> federica.trona@iasma.it</a></p> <p class="style17">Neuroethology of pheromone-plant odour interaction in the codling moth</p> <p>In the last years an increasing number of studies have given new insights on the mechanisms underlying the perception and coding of odour mixtures in insects. However, how sex pheromones and host plant volatiles interact along the olfactory system remains still poorly understood. By using a multimodal approach, including behavioural analysis, optical imaging of the primary olfactory centre, the antennal lobe (AL), and intracellular recordings of AL neurons, we studied how binary blends of the main pheromone component (codlemone) and three plant volatiles affected the behaviour and odour processing in the codling moth <em>Cydia pomonella</em>. In wind tunnel bioassays, males of <em>C. pomonella</em> were more attracted by the blends than by the single components. Optical imaging revealed that the presence of the plant volatile enhanced the response to a suboptimal dose of codlemone in the large pheromone-tuned glomerulus, the cumulus (Cu), while additive and suppressive interactions were observed in other areas of the AL. Intracellular recordings from projection neurons confirmed that the synergistic responses were confined to the Cu and some glomeruli in the macroglomerular complex. Hence, we demonstrate that behaviourally active blends of sex pheromone and host plant volatiles have a synergistic effect in the pheromone subsystem of the codling moth AL. Our physiological analysis suggests that this interaction may occur already at the peripheral olfactory level or as a result of presynaptic modulatory mechanisms.<hr> <p class="style16">37<br> <br>Rickard Ignell<sup>1</sup> and Joachim Schachtner<sup>2</sup></p> <p>1 Division of Chemical Ecology, Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Box 44, 230 53, Alnarp, Sweden.<br> 2 Department of Biology, Animal Physiology, Philipps-University, D-35032 Marburg, Germany.<br> <br><a href="mailto:Rickard.ignell@slu.se"> Rickard.ignell@slu.se</a></p> <p class="style17">Neuropeptides in the antennal lobe of <em>Aedes aegypti</em>, and changes in expression following blood feeding</p> <p>The sensory processes involved in capturing and amplifying behaviorally relevant stimuli, e.g. host and oviposition volatiles in the case of female <em>A. aegypti</em> mosquitoes, are critical steps for signal recognition and discrimination. Previous studies have shown that neuropeptide signaling in the olfactory system may play a significant role in shaping the physiology and behavior of insects. To unravel the neuropeptidome of the olfactory system of <em>A. aegypti</em>, we have employed the method of direct peptide profiling of single isolated antennal lobes by matrix assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS). In all, we reliably identified 26 mature products from 9 different neuropeptide precursors genes. In addition, we used immunocytochemical techniques to describe the cellular localization of the products of six of these genes. Through quantitative peptidomics we are currently determining which antennal lobe neuropeptides are differentially expressed after blood feeding. The results from this analysis will be used as a starting point to elucidate their function in the regulation of mosquito host and oviposition behaviors.<hr> <p class="style16">38<br> <br>Jan Kropf, Kathrin Bieringer, Christina Kelber, Wolfgang Rössler</p> <p>University of Würzburg, Biozentrum, Zoologie II, Am Hubland, D-97074 Würzburg<br> <br><a href="mailto:jan.kropf@uni-wuerzburg.de"> jan.kropf@uni-wuerzburg.de</a></p> <p class="style17">Sensory supply and sex-specficity of olfactory subsystems in the honeybee</p> <p>Insect antennae are covered with different types of sensilla housing olfactory receptor neurons (ORNs) that transmit olfactory input to the antennal lobe (AL). Honeybee (<em>Apis mellifera</em>) ORNs project via four different sensory tracts to four corresponding glomeruli clusters (T1-T4), where they synapse on local interneurons and projection (output) neurons (PNs). PNs convey the olfactory information to the mushroom bodies (MBs), higher sensory association centers and sites associated with learning and memory. Uniglomerular PNs project to the MBs via two parallel tracts forming a dual olfactory pathway, the medial and the lateral antennal lobe tract (m- and l-ALT). The role of parallel pathways in odor coding is unclear. To test different hypotheses for the function of a dual pathway to the MBs we investigated: 1. Whether the two pathways may carry information from distinct subsets of ORNs in different sensilla. 2. The two pathways may transmit information about different coding aspects of similar odors. The social lifestyle shared by social Hymenoptera involves many pheromonal and colony-specific odors that play important roles in the regulation of social organization. Honeybee drones almost exclusively have reproductive tasks and their involvement in social tasks is minor. Drone ALs were shown to contain less glomeruli compared to the female castes (Sandoz 2006, J Exp Biol). Besides, drone antennae lack Sensilla basiconica (SB), and the associated reduction of AL glomeruli mostly affects the T3 cluster (Nishino et al. 2009). Interestingly, the T3 cluster was shown to be mainly innervated by PNs of the m-ALT in honeybee workers (Kirschner et al. 2006). We tested the hypothesis whether SB ORNs preferentially project to the T3 cluster in workers, and whether their absence in drones may explain the reduction in the number of T3 glomeruli. We selectively labeled axonal projections of ORNs in SB in AL glomeruli and retrogradely stained the ALTs in drones to test whether only the m-ALT proportion of glomeruli is reduced. The results from sensilla stainings indicate that SB-associated ORNs mainly project into the T3 cluster of AL glomeruli. APT labelings in drones indicate that the m-ALT innervates less glomeruli compared to the m-ALT in workers. The two results combined suggest that information transmitted by SB associated ORNs is preferentially processed via the m-APT. The absence of SB and T3 glomeruli in drones may indicate that the m-APT carries specific information about colony odors in addition to other odors.<p>Supported by DFG SPP 1392<hr> <p class="style16">39<br> <br>Katrin C. Groh, Marcus C. Stensmyr, Ewald Grosse-Wilde, Bill S. Hansson</p> <p>Max-Planck-Institute for Chemical Ecology, Dep. of Neuroethology, Hans-Knöll-Straße 8, D-07745 Jena<br> <br><a href="mailto:kgroh@ice.mpg.de"> kgroh@ice.mpg.de</a></p> <p class="style17">The evolution of olfaction in hermit crabs</p> <p>Olfactory and gustatory senses are central for the detection of nutrients, conspecifics and dangers. Their characteristics depend on the available informative chemical stimuli of the inhabited environment. Insects show specific adaptations due to the necessity to perceive chemical cues. This adaptability can be retraced to the early stages of their evolution. The hexapods split from an arthropod progenitor and left the marine habitat in the very late Silurian 416 million years ago. Within the crustaceans at least five lineages independently succeeded in the transition from water to land. This results in a shift of the range of chemical stimuli from water soluble to air-borne substances. Despite the long time of independent development, insects and crustaceans show a parallel morphological evolution, sharing a connatural organization of olfactory organs and brain architecture. Considering a common aquatic ancestor and the morphological similarities we assume a similar but independent molecular evolution of the olfactory sense. Therefore we investigated the antennal transcriptome, electrophysiology and morphology of the terrestrial <em>Coenobita clypeatus</em>, paying special attention to gene families involved in chemosensory detection.<p> This project was supported by the Max Planck Society<hr> <p class="style16">40<br> <br>Virginie Party, Angela Rouyar, Didier Rochat1 and Michel Renou</p> <p>1 UMR1272 PISC, INRA UPMC Route de Saint-Cyr 78026 Versailles cedex, France<br> <br><a href="mailto:vparty@versailles.inra.fr"> vparty@versailles.inra.fr</a>; <a href="mailto:renou@versailles.inra.fr"> renou@versailles.inra.fr</a></p> <p class="style17">Masking effect of linalool on the pheromone response in <em>Spodoptera littoralis</em></p> <p>The localization of a sexual partner is a critical step in an insect s life. In moths, males respond by an upwind flight to the specific pheromone blend emitted by the females. The pheromone is detected by olfactory receptor neurons (Ph-ORNs) expressing narrowly tuned olfactory receptors. In natural conditions, pheromone is perceived in a complex background of plant volatile compounds (PVCs). PVCs are known to synergise or decrease attraction to pheromone, according to species, but the underlying mechanisms are still unknown. To understand the influence of environmental cues on immediate pheromone response we analyzed the effects of linalool, a general plant volatile, on response to pheromone in <em>Spodoptera littoralis</em>.<p>First, behavioural experiments with a locomotion compensator showed that whereas linalool alone has no behavioural effect; an addition of linalool during pheromone stimulation reversibly disrupted the orientation of males, mimicking the effects of stopping the pheromone stimulus. Linalool had an odour masking effect. But the orientation behaviour quickly recovered even if the linalool background was maintained.<p>Second, we analyzed the firing responses of Ph-ORNs to the main pheromone component, Z9E11-14:Ac (Ph-ORNs), in the presence of linalool under different temporal patterns. 1) A linalool background reduced the response to a Z9E11-14:Ac puff. 2) A puff of linalool during a sustained stimulation of Z9E11-14:Ac reversibly inhibited the response. 3) Pulses of linalool over a prolonged stimulation with Z9E11-14:Ac interrupted firing activity. 4) In the reverse experiment, pulses of Z9E11-14:Ac in a linalool background, Ph-ORNs still followed the pheromone pulses. Responses to pulses were shortened but firing decay and contrast remained similar both with and without background. Thus, the background odor preserved the temporal parameters of a specific signal with decreasing the response intensity.<p>We conclude that, linalool reduces the sensitivity to pheromone but does not affect the coding of the signal temporal parameters. The masking effect of linalool background seems for the male similar to a reduction of the perceived concentration of pheromone. The orientation behaviour quickly recovered, although the linalool background was maintained, showing that a change of the stimulus intensity might be more important than its absolute value.<hr> <p class="style16">41<br> <br>Dieter Wicher, Vardanush Sargsyan, Merid N. Getahun, Shannon B. Olsson, Bill S. Hansson</p> <p>Max Planck Institute for Chemical Ecology, Hans-Knöll-St. 8, D-07745 Jena, Germany<br> <br><a href="mailto:dwicher@ice.mpg.de"> dwicher@ice.mpg.de</a></p> <p class="style17">The function of the Drosophila odorant coreceptor is regulated by PKC-mediated phosphorylation</p> <p>Insect odorant receptors (ORs) are heterodimers composed of an odorant-specific receptor protein and a co-receptor protein (Orco) that forms an ion channel. Heterologously expressed insect ORs are activated via an ionotropic and a metabotropic pathway. The latter one leads to cAMP production which in turn activates the Orco channel. We here report a mechanism that regulates the cAMP-sensitivity of Orco. Inhibition of phospholipase C (PLC) with U73122 prevented the Orco activation by cAMP. A similar effect was obtained by inhibition of protein kinase C (PKC) with Gö6976 . However, stimulation of PKC by OAG, a diacylglycerol analog, or phorbol myristate acetate (PMA) activated Orco even in the absence of cAMP. Mutation of the five PKC phosphorylation sites in Orco eliminated its sensitivity to cAMP. The contribution of metabotropic signaling to the insect odor response remains elusive. We thus tested how manipulation of PKC activity <em>in vivo</em> affects the odor response of olfactory sensory neurons (OSNs). For this sake we combined single sensillum electrophysiological recordings with microinjection of agents affecting PLC and PKC function and observed the OSN response to odorant stimulation. Injection of the PLC inhibitor U73122 or the PKC inhibitor Gö6976 into sensilla reduced the OSN response to odor pulses. By contrast, injection of the PKC activators OAG or PMA enhanced the odor response. We conclude that the phosphorylation state of Orco regulates the OR function and contributes to shaping the OSN odor response.<p> This project was supported by the Max Planck Society.<hr> <p class="style16">42<br> <br>Hidefumi Mitsuno<sup>1</sup>, Takeshi Sakurai<sup>1</sup>, Hiroyuki Mitsuhashi<sup>2</sup>, and Ryohei Kanzaki<sup>1</sup></p> <p>1 Research Center for Advanced Science and Technology, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8904, Japan.<br> 2 Graduate School of Information Science and Technology, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.<br> <br><a href="mailto:mitsuno@brain.imi.i.u-tokyo.ac.jp"> mitsuno@brain.imi.i.u-tokyo.ac.jp</a> </p> <p class="style17">Development of an odorant sensor using Sf21 cells expressing insect odorant receptors</p> <p>Currently existing odorant sensors are mainly fabricated based on metal-oxide semiconductor devices, quartz crystal microbalances, surface plasmon resonance methods or surface acoustic wave detectors (Arshak et al., 2004). These sensors have been studied for improving on various parameters, such as sensitivity, selectivity, response speed, and portability. However, it has been difficult to develop odorant sensor elements that incorporate a combination of desirable properties. In contrast, living organisms, especially insects, use numerous olfactory sensory cells, which express odorant receptors, to sensitively detect environmental odorants in real time. So far, we have developed a compact odorant sensor that consists of a multichannel fluidic device and <em>Xenopus laevis </em> oocytes expressing insect odorant receptors (Misawa et al., 2010). Although this odorant sensor possessed fast responsiveness and good portability, it had some technical disadvantages in terms of the stablility of response measurements in the oocytes. Here, we report the development of new odorant sensor elements that enable us to acquire stable odorant response measurements. We introduced insect odorant receptors and the Or83b coreceptor (Orco) as well as a calcium sensor protein, GCaMP3, into <em>Spodoptera frugiperda</em> Sf21 cells to construct sensor cell lines. When these cells were stimulated with a set of odorants in solution, intracellular calcium as monitored by fluorescence imaging showed sensitive responses in accordance to the ligand specificity of the expressed odorant receptors. These results show that our sensor cells can be applied as odorant sensor elements that detect various kinds of odorants with high sensitivity, selectivity, and stability.<p> This work was supported by Secom Science and Technology Foundation.<p> Arshak K., Moore E., Lyons G., Harris J., Clifford S. (2004) Sensor Review 24: 181-198.<br> Misawa N., Mitsuno H., Kanzaki R., Takeuchi S. (2010) Proc. Natl. Acad. Sci. USA 107: 15340-15344.<hr> <p class="style16">43<br> <br>Jérôme Frei<sup>1</sup>, Christian Starkenmann<sup>2</sup>, Myriam Troccaz<sup>2</sup>, Laurent Wunsche<sup>2</sup> and Patrick Guerin<sup>1</sup></p> <p>1 Institute of Biology, University of Neuchâtel, CH-2000 Neuchâtel, Switzerland<br> 2 Firmenich SA, Corporate and R&D Division, CH-1211 Geneva, Switzerland<br> <br><a href="mailto:jerome.frei@unine.ch"> jerome.frei@unine.ch</a></p> <p class="style17">Behavioural response of the principal African malaria vector Anopheles gambiae to sweat samples inoculated with different human skin bacteria from the axillary region.</p> <p>Due to its highly anthropophilic host seeking behaviour, <em>Anopheles gambiae</em>, the principal African malaria mosquito has a severe impact on human health. To locate and differentiate between humans this vector uses odour cues. Human body odour mainly takes its origin from bacterial decomposition of sweat glands secretions. Fresh sweat without any bacteria is almost odourless. Humans have distinct skin bacteria populations both in terms of diversity and density, making bacteria populations a key actor in shaping humans personal odour signatures. To provide more information on this topic we investigated the response of <em>An. gambiae</em> in a dual choice olfactometer to odorous sweat samples resulting from the inoculation with three bacteria species from the axillary region (<em>Staphylococcus epidermidis</em>, <em>Corynebacterium jeikeium</em> and <em>Staphylococcus haemolyticus</em>). The sweat samples originated from two sterilized pools of human apocrine and ecrine secretions collected from the axillae of 49 Caucasian volunteers (24 men and 25 women). When confronted with two incubated sweat sources, one resulting from sterile female (or male) sweat and the other from the inoculated female (or male) sweat with one of the bacteria species, the mosquitoes always preferred the bacterium-inoculated sweat. Mosquitoes showed no preference for male or female sweat samples when they had not been inoculated with a bacterium. After inoculation the sweat substrates could be discriminated by the vector. It is concluded that all the 3 tested bacteria species are key actors in the odour-mediated host vector interaction. Despite the fact that axillary sweat was used as a substrate and given that <em>An. gambiae</em> shows a preference for the ankles as a biting site, the results suggest that odour from the axillary region nevertheless plays a significant role in the process of host location. Moreover it underlines that not only the bacterium species but also the substrate in which it grows contribute to the odour specificity which may be involved in the process of differential attractiveness.<hr> <p class="style16">44<br> <br>Peter Witzgall, Paul Becher, Marie Bengtsson </p> <p>Chemical Ecology Group, SLU, Alnarp, Sweeden<br> <br><a href="mailto:Peter.Witzgall@slu.se"> Peter.Witzgall@slu.se</a></p> <p class="style17">Microbial odors mediate host finding in insect herbivores</p> <p>Attraction of the fruit fly <em>Drosophila melanogaster</em> to a blend of yeast volatiles with acetic acid as a main attractant compound (Becher et al. 2010, 2011) demonstrates the significance of ionotropic receptors (IRs) in <em>Drosophila </em> behavioral ecology. IRs have been discovered recently, they are tuned to acids and other microbial odors (Benton et al. 2009, Ai et al. 2010). With this in mind, we have investigated the role of yeasts for host finding and oviposition in other insect herbivores. We conclude that plant-yeast-insect interactions are more widespread than previously assumed, and that yeasts and other micro-organisms are important for our understanding of the ecology of insect herbivores and their evolutionary diversification. The traditional bi-trophic plant-insect niche concept must be updated to a tri-trophic niche concept, in order to accomodate for the role of micro-organisms in host-finding (Singer and Stireman 2005). This will be illustrated with results from current studies.<p>Ai M, Min S, Grosjean Y, Leblanc C, Bell R, Benton R, Suh GSB. 2010. Acid sensing by the <em>Drosophila </em> olfactory system. Nature 468:691-U112<br> Becher PG, Bengtsson M, Hansson BS, Witzgall P. 2010. Flying the fly: long-range flight behavior of <em>Drosophila melanogaster</em> to attractive odors. J chem Ecol 36:599-607<br> Becher PG, Flick G, Rozpedowska E, Lebreton S, Larsson MC, Hansson BS, Piskur J, Witzgall P, Bengtsson M. 2011. Yeast links the fly to fruit. (submitted)<br> Benton R, Vannice KS, Gomez-Diaz C, Vosshall LB. 2009. Variant ionotropic glutamate receptors as chemosensory receptors in <em>Drosophila </em>. Cell 136:149-162.<br> Singer MS, Stireman JO. 2005. The tri-trophic niche concept and adaptive radiation of phytophagous insects. Ecol Lett 8:1247-1255.<hr> <p class="style16">45<br> <br>Andreas Reinecke<sup>1</sup>, Anna Henning<sup>1</sup>; Kesavan Subaharan<sup>2</sup>, Shannon Olsson<sup>1</sup>, Markus Knaden<sup>1</sup>, Bill S. Hansson<sup>1</sup></p> <p>1 Max Planck Institute for Chemical Ecology, Hans Knöll Str. 8, D-07745 Jena, Germany,<br> 2 Central Plantations Crops Research Institute, 671124 Kasaragot, Kerala, India,<br> <br><a href="mailto:areinecke@ice.mpg.de"> areinecke@ice.mpg.de</a></p> <p class="style17">Smelling the difference: Sensory and chemical correlates to host plant preferences in ovipositing <em>Manduca sexta</em> </p> <p>We performed a comprehensive analysis of oviposition preferences, sensory and behavioural responses to host plant derived volatiles in gravid <em>M. sexta</em> females. Individual <em>Manduca</em> larvae devastate <em>Nicotiana attenuata</em> plants, while the species is a pollinator to Datura wrightii, which tolerates feeding-damage to a certain degree. Feeding-damaged <em>N.attenuata</em> plants also attract parasitoids and predators. In our experiments with non-flowering plants, gravid females correspondingly prefer intact plants as compared to feeding-damaged tobacco plants. On the other hand, females do not discriminate between damaged and intact <em>D. wrightii</em> plants. At the species level, <em>D. wrightii</em> is preferred to <em>N.attenuata</em>. Behavioural data and flight tunnel experiments show that olfactory cues alone suffice not only to attract gravid females to host species, but also to establish a hierarchy of preferences ranging from non-hosts through accepted but not preferred to highly preferred host plants. GC analyses of headspace samples combined with single sensillum electrophysiology and principal component analyses of the perceived fraction of volatile blends indicate that compounds from diverse functional classes, including fatty acids emanating from the larval faeces, contribute to the discrimination capacity of the egg-depositing moth. Single sensillum recordings reveal that <em>N.attenuata</em> and <em>D. wrightii</em> odours elicit species and condition-specific responses to host components  providing a sensory fingerprint conveyed to the brain.<p> Supported by Max Planck Society<hr> <p class="style16">46<br> <br>Elisabeth J. Eilers<sup>1,2</sup>, Giovanni Talarico<sup>1</sup>, Bill S. Hansson<sup>1</sup>, Monika Hilker<sup>2</sup>, <u>Andreas Reinecke</u><sup>1</sup></p> <p>1 Max Planck Insitute for Chemical Ecology, Department of Evolutionary Neuroethology, Jena, Germany<br> 2 Freie Universität Berlin, Department of Applied Zoology / Animal Ecology, Berlin, Germany<br> <br><a href="mailto:areinecke@ice.mpg.de"> areinecke@ice.mpg.de</a></p> <p class="style17">Sensing the underground: Chemoreceptive organs of rhizophagous <em>Melolontha melolontha</em> white grubs</p> <p>Despite of its status as a major pest in European agriculture and horticulture, little is known about the chemosensory system, enabling the root-feeding <em>Melolontha melolontha</em> (Coleoptera: Scarabaeidae) larva to orient belowground.<br>In contradiction to the multitude of morphological specifications for different Scarabaeid larvae, which appear rather adumbrated (1-3), in-depth specifications of larval chemosensory sensilla are still lacking to date. However, these specifications are essential to assign morphology to corresponding chemosensory function in larval host plant location.<p>We present an overview of the chemosensory structures on the head appendages of <em>M. melolontha</em> larvae based on scanning and transmission electron microscopy. Along morphological criteria we identified olfactory sensilla predominantly on the antennae but also on the maxillary and the labial palps. These are either pore plate sensilla on the antennae or peg like sensilla with multiple wall pores on the maxillary palps, the labial palps and the antennae. Contact chemoreceptive sensilla, characterized by a terminal pore, are present on all three appendages, especially at the tip. Putative mechano-, hygro- and thermoreceptive sensilla have been identified as well. <p>Electrophysiological studies using compounds identified in the rhizosphere of the host plant <em>Taraxacum officinale</em> or known to be behaviourally active are currently conducted to link sensillum morphology to function. These data will complete the survey on the chemosensory capabilities of root feeding white grubs. <p>(1) MA Moron, JR Salvadori, P Entomol Soc Wash 108, 511 (2006).<br> (2) CM Deschodt, CH Scholtz, U Kryger, Afr Entomol 17, 43 (2009).<br> (3) MLU Jerath, KL Unny, Coleopts Bull 19, 59 (1965).<p>Supported by Deutsche Forschungsgemeinschaft (P.S. RE 302311) & Max Planck Society<hr> <p class="style16">47<br> <br>Chen Yi-chun<sup>1,2</sup>, Mishra Dushyant<sup>1,2</sup>, Schmitt Linda<sup>1</sup>, Schmuker Michael<sup>3,4</sup>, Gerber Bertram<sup>1,2</sup></p> <p>1 Department of Neurobiology and Genetics, Biozentrum, Universität Würzburg, Würzburg, Germany<br> 2 Department of Genetics, Institute of Biology, Universität Leipzig, Leipzig, Germany<br> 3 Neuroinformatics and Theoretical Neuroscience, Institute for Biology, Freie Universität Berlin, Berlin, Germany<br> 4 Bernstein Center for Computational Neuroscience Berlin, Berlin, Germany<br> <br><a href="mailto:chen.yi-chun@biozentrum.uni-wuerzburg.de"> chen.yi-chun@biozentrum.uni-wuerzburg.de</a></p> <p class="style17">A Behavioural Odour-Similarity 'Space' in Larval <em>Drosophila</em></p> <p>To provide a behaviour-based estimate of odour similarity in larval <em>Drosophila</em>, we use four recognition-type experiments: (i) We train larvae to associate an odour with food, and then test whether they would regard another odour as the same as the trained one. (ii) We train larvae to associate an odour with food, and test whether they prefer the trained odour against a novel, non-trained one. (iii) We train larvae differentially to associate one odour with food, but not the other one, and test whether they prefer the rewarded against the non-rewarded odour. (iv) In an experiment like (iii), we test the larvae after a 30 min-break. This yields a combined, task-independent estimate of perceived difference between odour-pairs. Comparing these perceived differences to published measures of physico-chemical difference reveals a weak correlation. A notable exception are 3-octanol and benzaldehyde, which are distinct in published accounts of chemical similarity, and in terms of their published sensory representation, but nevertheless are consistently regarded as the most similar of the ten odour pairs employed. It thus appears as if at least some aspects of olfactory perception are 'computed' in post-receptor circuits <em>on the basis of</em> sensory signals, rather than being immediately <em>given</em> by them.<hr> <p class="style16">48<br> <br>Sophie Kromann<sup>1</sup>, Saveer Ahmed<sup>1</sup>, Paul Becher<sup>1</sup>, Marie Bengtsson<sup>1</sup>, Göran Birgersson<sup>1</sup>, Peter Witzgall<sup>1</sup>, Anna Balkenius, Bill S. Hansson<sup>2</sup> and Rickard Ignell<sup>1</sup></p> <p>1 Department of Plant Protection Biology, Institute of Chemical Ecology, Swedish University of Agricultural Sciences, Sundsvägen 14, SE-23053 Alnarp, Sweden<br> 2 Department of Neuroethology, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straße 8, D-07745 Jena, Germany<br> <br><a href="mailto:Sophie.Kromann@slu.se"> Sophie.Kromann@slu.se</a></p> <p class="style17">Modulation of odour-evoked signals in the antennal lobe of <em>Spodoptera littoralis</em></p> <p>Moth behaviour is largely regulated by olfaction. Like many other insects, moths depend on odour stimuli to locate food sources, mates and sites relevant for oviposition. Research into moth olfaction has mainly been focussing on the male response to conspecific female pheromones, and little is known about the olfactory system of females. In addition, we have limited understanding of how the system in both males and females is modulated by physiological status.<p>In wind tunnel experiments we have shown that the mating status of <em>Spodoptera littoralis</em> informs behavioural response to resources: mated females are more attracted to oviposition host plants, while unmated females are more attracted to flowers, i.e. food sources. Male <em>S. littoralis</em> also show mating-induced differences in behaviour; during subsequent hours after mating, males show no attraction to pheromones and a lowered response to host plant odours compared to unmated males. At the onset of the following scotophase, behavioural attractiveness to pheromone and host plant odours is restored. Contrary, behavioural attraction to flower odours does not change post mating.<p>At the peripheral olfactory level, gas chromatograph coupled electroantennodetection (GC-EAD) analyses reveal 17 antennal active components from food source headspace and 6 active components from oviposition substrate headspace in virgin and mated females. Analyses of antennae from virgin and mated males reveal 14 active components from food source and 6 from oviposition host plant regardless of mating status.<p>Through calcium imaging of the primary olfactory centre, the antennal lobe, of male and female <em>S. littoralis</em> we show modulation at the presynaptic level of the antennal lobes in both sexes. Food source headspace elicits a stronger calcium signal in virgin females compared to mated and, contrary, oviposition substrate headspace elicits stronger signal in mated females than in virgins. Analysis of individual components of the headspaces reveals a similar modulation of calcium signal strength to a subset of the components contained in the headspaces. For the males, the sensitivity to food odours and the signals these odours induce at the presynaptic level is independent of mating status. However, mated males show a reduction of the pheromone- and oviposition substrate-induce calcium signal 3 hours after mating, whereas there is no significant difference between the calcium signals in virgin and mated males 24 hours post mating.<hr> <p class="style16">49<br> <br>Carolina Gomez-Diaz, Jaime Humberto Reina, Marion Graf and Richard Benton</p> <p>Center for Integrative Genomics, University of Lausanne, CH-1015, Lausanne<br> <br><a href="mailto:Carolina.GomezDiaz@unil.ch"> Carolina.GomezDiaz@unil.ch</a></p> <p class="style17">Molecular and biochemical dissection ofDrosophila SNMP in pheromone detection</p> <p>CD36 transmembrane proteinsare involved in diversecellular processes across metazoans such as lipid uptake, cell adhesion and innate immune detection. Despite their widespread functions,the molecularmechanisms by which theseproteins act are unclear.A subfamily ofCD36-related proteins in insects, the Sensory Neuron Membrane Proteins (SNMPs), have been shown to be expressed selectively in pheromone-sensing sensilla and localise to the ciliated dendrites of olfactory sensory neurons.Through genetic analysis in Drosophila melanogaster, we previously showed that SNMPacts together with the OBP LUSH and the pheromone receptor complex, OR67d/ORCO, inmediating neuronal activation by the pheromone cis-vaccenyl acetate.How SNMP collaborates with OBPs and ORs in mediating pheromone-evoked activity in olfactory ciliaremains an outstanding question. <p> We are performing a large-scale in vivo structure/function analysis of SNMP, comprising a full-protein deletion scan, site-directed mutagenesis of predicted sites of post-translational modification and other evolutionarily conserved residues and functional complementation with SNMPs from other insect species.Analysis of thesubcellular localisation and physiological activity of these mutant proteinsis beginning to definedomains that are essential for the localisation and pheromone recognition properties of SNMP.In parallel, we are reconstituting SNMP function in heterologous cells to allow us to investigate the existence of biochemical interactions of SNMP with labelled pheromone ligands, OBPs andORs.Together our experiments provideinsights into both the molecular basis of pheromone detection in insects and - more generally - theconserved and divergent molecular mechanisms of CD36 protein function.<hr> <p class="style16">50<br> <br>Merid N Getahun, Shannon B Olsson, Sofia Lavista Llanos, Dieter Wicher and Bill S Hannsson</p> <p>Max Planck Institute for Chemical Ecology, Hans-Knöll-St. 8, D-07745 Jena, Germany<br> <br><a href="mailto:mgetahun@ice.mpg.de"> mgetahun@ice.mpg.de</a></p> <p class="style17">Temporal coding of repeated pulsed odors stimulation in an olfactory receptor neurons of <em>Drosophila melanogaster</em>.</p> <p>Insects are highly dependent on the sense of smell. Their olfactory system should therefore optimize both sensitivity as well as the speed of reception and transduction. To investigate this hypothesis, we used electrophysiological techniques in wild type and transgenic flies. Olfactory sensory neurons (OSNs) expressing diverse olfactory receptors were challenged with odorant stimulation presented at different frequencies (0.5 Hz to 10 Hz), with 10 consecutive pulses. The olfactory response dynamics of OSNs was found to be frequency dependent. em>Drosophila</em> receptors could accurately code temporal information up to 10Hz. The response of IR and GR expressing OSNs exhibited both a reduced firing rate and longer latency as compared to ORs, which could be due to a different signaling mechanism. Despite the reduced response, GR carrying OSNs could follow pulses up to 10Hz, while ORs could follow only up to 5Hz. The pulse-following capacity of a given receptor was found to be dependent on the outcome of transduction (i.e. depolarization or hyperpolarization of the OSN). The location of the receptor also affected the capacity for pulse following. For example, OSNs expressing the Pb1 receptor on the maxillary palp could easily code 5Hz stimulations, while antennal OSNs exhibited functional adaptation. Furthermore, the capacity for pulse following was dependent on the signal transduction mechanism of the odor sensory neuron. In transgenic flies carrying mutations in Orco phosphorolation sites, olfactory responses exhibited reduced firing rates, duration, and frequency dependence. This demonstrates that Orco-dependent metabotropic signaling regulates response kinetics and improves pulse following in OR expressing OSNs. ORs have merged ionotropic with metabotropic signaling, therefore optimizing the speed of olfactory signal transduction as well as OSN sensitivity. The change in response dynamics over the course of repeated stimulation could have behavioral significance for host finding and acceptance.<p> This project was supported by the Max Planck Society<hr> <p class="style16">51<br> <br>Christine Mi²bach<sup>1</sup>, Hany Dweck<sup>1</sup>, Heiko Vogel<sup>2</sup>, Marcus C. Stensmyr<sup>1</sup>, Ewald-Grosse-Wilde<sup>1</sup>, Bill S. Hansson<sup>1</sup></p> <p>1 Max-Planck-Institut for Chemical Ecology, Dept. of Neuroethology, Hans-Knöll-Straße 8, 07745 Jena, Germany<br> 2 Max-Planck-Institut for Chemical Ecology, Dept. of Entomologie, Hans-Knöll-Straße 8, 07745 Jena, Germany<br> <br><a href="mailto:cmissbach@ice.mpg.de"> cmissbach@ice.mpg.de</a></p> <p class="style17">Olfaction in the jumping bristletail <em>Lepismachilis y-signata</em>  A 390 million-year-old insect nose?</p> <p>Olfaction is crucial for many insect behaviors, such as locating food, oviposition sites and for intraspecific communication. Most data on insect olfaction derive from studies on pterygote insects. We have investigated the sense of smell in the primary wingless bristletail <em>Lepismachilis y-signata</em> (Archaeognatha: Machilidae), which belongs to an ancient insect taxon that is supposed to be the sistergroup of the remaining insects (i.e. the Ectognatha). The Archaeognatha emerged about 390 million years ago, coexisting at the time with ferns, club mosses and moss species as well as the first terrestrial fungi. Interestingly, even today bristletails mainly use these plant groups as food sources; similarly, their spectrum of enemies essentially has not changed. Hence, the bristletail s olfactory system could well be envisioned to have been largely conserved over a vast period of time. Here we present a detailed analysis of the olfactory system of the bristletail, using electrophysiological, morphological and molecular techniques. We demonstrate that <em>L. y-signata</em> possesses an acute but reduced olfactory system, displaying a unique morphological and molecular makeup among extant insects.<p> This project was supported by the Max Planck Society<hr> <p class="style16">52<br> <br>Jeanine Linz, Bill S. Hansson, Marcus C. Stensmyr</p> <p>Max Planck Institute for Chemical Ecology, Department of Evolutionary Neuroethology, Hans-Knöll-Str. 8, 07745 Jena, Germany<br> <br><a href="mailto:jlinz@ice.mpg.de"> jlinz@ice.mpg.de</a></p> <p class="style17">That´s my place - Olfactory adaptations in specialized <em>Drosophila</em> flies towards their host</p> <p>The chemical senses directly interface an insect with its environment. Adaptations of the chemical sensory system might therefore have occurred during the evolution of ecological specialization. The <em>Drosophila melanogaster</em> species subgroup shows a considerable interspecific variation - ranging from extreme specialists to generalists and from endemic to cosmopolitan species. These circumstances provide an ideal background to study the evolution of host specialization and, furthermore, how these processes lead to adaptations within the insect olfactory system. In our study, we followed an approach by using <em>melanogaster</em> sibling species with different host specificity and ecology. Here, <em>Drosophila erecta</em> is remarkable for its ecological specialization for feeding and breeding on screw pine tree (<em>Pandanus</em> ssp.) fruits. By performing GC-EAD and GC-MS we identified biologically active components guiding the flies to their oviposition sites. First results let us assume that non-host associated siblings differ in their olfactory response from the host associated. Behavioural experiments and immunohistological analysis of the olfactory systems are ongoing experiments.<p> This project was supported by the Max Planck Society.<hr> <p class="style16">53<br> <br>Andrea Clavijo Mc Cormick<sup>1</sup>, Andreas Reinecke<sup>2</sup>, Bill S. Hansson<sup>2</sup> Jonathan Gershenzon<sup>1</sup> and Sybille B. Unsicker<sup>1</sup></p> <p> Max Planck Institute for Chemical Ecology 1Department of Biochemistry, 2 Department of Evolutionary Neuroethology<br> <br><a href="mailto:amccormick@ice.mpg.de"> amccormick@ice.mpg.de</a></p> <p class="style17">What do parasitoids understand when poplars talk?</p> <p>Plants emit volatile organic compounds (VOC) in response to herbivore attack and hereby attract natural enemies of the herbivores (indirect defense) (1-2). Predators and parasitoids may obtain specific information (i.e. prey species identity, most suitable instar of its prey) from herbivore induced volatiles (HIV)(3-5). However, volatile emission patterns vary highly depending on factors such as plant sex, genotype, tissue, phenological state and environmental conditions (1-2). So a question emerges, how reliable are these signals? The braconid wasp <em>Glyptapanteles liparidis</em> is a parasitoid of early instar gypsy moth (<em>Lymantria dispar</em>), caterpillars. We hypothesize that <em>G. liparidis</em> can discriminate between its host species (<em>L. dispar</em>) and a non host species (<em>Laothoe populi</em>), and to identify its preferred host instar (2<sup>nd</sup> instar) based on the volatile blends emitted by black poplar (<em>Populus nigra</em>) upon feeding. To test our hypothesis we compared the volatile blends of <em>P. nigra</em> after attack by the host <em>L. dispar</em> and the non-host <em>L. populi</em>, as well as by two different <em>L. dispar</em> instars (2<sup>nd</sup> and 5<sup>nd</sup>). Temporal patterns of volatile emission were measured at 6 time points: 6, 12, 24, 30, 36 and 48 h after damage. More than 30 compounds, mostly monoterpenes and sesquiterpenes, were identified and quantified by GC-MS and GC-FID analyses. Results indicate that P. nigra trees emit volatile blends that differ quantitatively depending on the herbivore species and instar attacking, and that the emission pattern of single compounds varies over time, showing major differences during the day measurements at 24 and 38 hours after damage. Synthetic standards for 12 compounds, identified in the volatile blend of P. nigra including (E)-2-Hexenal, (Z)-3-Hexenol, (E)-²-Ocimene, Linalool, ²-Caryophyllene and (E)-²-Farnesene, were used for Electroantennographic detection (EAG) tests, showing different magnitudes of response. Dose-response curves were carried out for the compounds showing higher response values. Current experiments involve testing <em> G. liparidis</em> behavior to full leaf samples, as well as to single synthetic compounds and blends.<p>1. Turlings, T. C. J. and Ton, J. Current Opinion in Plant Biology. 9, 421-427, (2006).<br> 2. Dicke, M. and Baldwin, I. T. Trends in Plant Science. 15, 167-175, (2010).<br> 3. De Moraes, C. M. et al. Nature. 393, 570-573, (1998).<br> 4. Yoneya, K. et al. Physiological Entomology. 34, 379-386, (2009).<br> 5. De Boer, J. G. et al. Animal Behavior. 69, 869-879, (2005). <hr> <p class="style16">54<br> <br>Polina Volkova <sup>1</sup>, Vladislav Soukhovolsky <sup>2</sup></p> <p>1 International Scientific Center for Organism Extreme States Research SB RAS, Krasnoyarsk, Russia<br> 2 V.N. Sukachev Institute of forest SB RAS, Krasnoyarsk, Russia<br> <br><a href="mailto:polina72000@mail.ru"> polina72000@mail.ru</a></p> <p class="style17">Patterns in ratios of insect pheromone components.</p> <p>Interest to regularities in pheromone components ratios is driven by the belief that revealing such regularities would help to determine if multicomponent pheromones carry any other information besides species-specifity. Presented work is devoted to finding patterns in ratios of Lepidoptera insects pheromone components.<p> Pheromone components were ranged starting from the major component, which was assigned rank 1, following by second component assigned rank 2 and so on. A share of jth component molecules from total number of molecules in a pheromone sample was denoted as pj.<p> For every pheromone component of a certain insect species component s rank and corresponding pj value was mapped onto a coordinate plane (logarithmical coordinates). It was found that marked points lie on a line:<p> <em> ln p(j)=ln p(1)-b ln j</em> (1)<br> where <em>p(1)</em> is a share of major pheromone component s molecules in a sample, <em>b</em> is a gradient of a line and j is the rank of a component. Such dependence between the rank and frequency of occurrence (in this case  occurrence of pheromone molecules) is a classic rank distribution, known as Zipf law:<p> <em>p(j)=p(1)/j<sup>b</sup></em> (2)<br> So if (2) holds true for all species, then there is a correspondence law for values <em>p(1)</em> and <em>b</em>, which is common to all species with the same number of pheromone components. And in fact, there is a close fit of theoretical and field data (www.pherobase.com).<hr> <p class="style16">55<br> <br>Svetlana Plotnikova</p> <p>Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, St. Petersburg, Russia<br> <p> </p> <p class="style17">Olfactory and tactile fibers of antennas and optic fibers terminating in mushroom bodies of <em>Aeshna grandis</em></p> <p>Do dragonflies have an olfactory system remains an open question. Several researchers using electron microscope found on the end of antenna receptors of smells of some plants (Gaino E, Rebpra M 2001; Rebora M. Salerno G, Piersent S, Giano E 2009). We found a nerve coming from antenna to supraesophageal ganglion with little ganglion on it, on which are terminating sensitive fibers, both tactile and olfactory. This little ganglion contains interneurons connecting it with protocerebrum. During his visit to the laboratory of Neurophysiology of invertebrates of the Institute of Evolutionary Physiology and Biochemistry N. Strausfeld using the slides of Aleksey Zavarzin found in this little ganglion the olfactory glomerula and so proved the existence of olfactory endings. Olfactory and tactile pathways terminate on dendrites of Kenyon sells, and also direct optic pathways from optic lobes terminate there. Kenyon sells transfer impulses through pedunculus to the lobes of mushroom bodies. From the lobes of mushroom bodies we determined the existence of the direct fibers to the ventral code. <p>In addition referred little ganglion contains motor neurons of antennas muscles, and accepts descending fibers from the lobes of mushroom bodies.<hr> <p class="style16">56<br> <br>A. François<sup>1 ,2</sup>, M. Grauso<sup>1 </sup>, F. Bozzolan<sup>2</sup>,T. Chertemps<sup>2</sup>, N. Montagné<sup>2</sup>, E. Demondion<sup>1</sup>, S. Debernard<sup>2</sup> and P. Lucas<sup>1</sup></p> <p>1 UMR 1272 Physiologie de l Insecte : Signalisation et Communication, INRA Versailles,<br><p> 2 Université Pierre et Marie Curie Paris, France<br> <br><a href="mailto:adrien.francois@versailles.inra.fr"> adrien.francois@versailles.inra.fr</a></p> <p class="style17">Molecular characterization of a calcium-dependent chloride channel involved in moth olfactory transduction</p> <p>Female moths emit a sex pheromone to attract conspecific males. The sex pheromone detection system of moths is an extremely favorable model to study the olfaction mechanisms because it is highly specialized and it implies few known and available ligands. The binding of odorant molecules to their cognate receptor proteins in olfactory receptor neurons (ORNs) opens different ion channel populations, generating a graded depolarization that leads to the firing of action potentials. Our lab wants to get an integrative understanding of the molecular mechanisms of olfactory transduction in a Noctuid moth, <em> Spodoptera littoralis</em>. We recently identified in ORNs a calcium-gated chloride current (Pézier et al, J. Neuroscience, 2010). The biophysical properties of this current have been described <em> in vitro</em> and <em> in vivo</em> (monosensillar) recordings suggested that it is involved in ORN repolarization. To identify the molecular properties of the channel underlying this current, we screened an antennal EST library from <em> S. littoralis</em> males. We identified five cDNAs belonging to two gene families which have been identified as calcium-dependent chloride channels in vertebrates: bestrophins and anoctamins (TMEM16). Expression patterns of the corresponding genes were studied between tissues and during development by RT-PCR and qPCR, leading to the identification of two adult antennal-enriched genes putatively involved in olfactory transduction. A bestrophin candidate has been expressed by transitory transfection in Chinese Hamster Ovary (CHO) cells. When dialyzed with calcium, transfected CHO cells exhibited a chloride current with biophysical similarities to the chloride current observed in ORNs, leading us to hypothesize that the calcium-gated chloride channel of moth ORNs is encoded by a bestrophin. We are currently testing this hypothesis by <em> in vivo</em> electrophysiological and behavioral experiments using RNA interference.<hr> <p class="style16">57<br> <br>Abu Farhan, Markus Knaden, and Bill S. Hansson</p> <p>Max Planck Institute for Chemical Ecology, Beutenberg Campus, Jena, Germany<br> <br><a href="mailto:afarhan@ice.mpg.de"> afarhan@ice.mpg.de</a></p> <p class="style17">Feeding status modulates peripheral olfactory sensitivity and behavior in <em> Drosophila</em></p> <p>Modulation and plasticity are key functions of all organisms for adapting to a changing environment and stress. Examples are blood-feeding insects, which after a blood meal switch their olfactory preference from host odors to odors specific for oviposition sites (1-3). We used the olfactory circuit of Drosophila as a well established model (4-7) to investigate whether the feeding status modulates the flies physiological and behavioral responses to odors. The main peripheral part of the olfactory circuit of <em> Drosophila</em> is represented by sensilla on the third antennal segment, where volatiles are detected via ca. 1200 olfactory sensory neurons (OSNs). Here, we show that starved flies have a decreased behavioral threshold to odors, while the sensitivity of OSNs is increased after starvation. The change in behavioral and physiological responsiveness was not restricted to food odors, but was found also in non-food odors like cis-vaccenyl acetate (CVA) and benzaldehyde. We then tested, whether the starvation effect on behavioral and physiological responsiveness was reversed by restarted feeding. When starved flies got access to sucrose both their behavior and their sensitivity resembled that of fed flies already 1 hour after feeding. The increased behavioral response of starved flies and their increased olfactory sensitivity at the level of the antenna demonstrate that the <em> Drosophila</em> olfactory circuit is modulated by the feeding state. The sensitivity is increased for both food and non-food odors. Hence, starved flies seem to be tuned not only to locate potential food sources from long distance, but in addition to evaluate food quality and the presence of conspecifics efficiently.<p>1. E. E. Davis, J. Insect Physiol. 30, 179 (1984).<br> 2. K. P. Siju, S. R. Hill, B. S. Hansson, R. Ignell, J. Insect Physiol. 56, 659 (Jun, 2010).<br> 3. C. J. Denotter, T. Tchicaya, A. M. Schutte, Physiological Entomology 16, 173 (Jun, 1991).<br> 4. L. B. Vosshall, A. M. Wong, R. Axel, Cell 102, 147 (Jul, 2000).<br> 5. E. A. Hallem, J. R. Carlson, Cell 125, 143 (Apr, 2006). 6. M. de Bruyne, K. Foster, J. R. Carlson, Neuron 30, 537 (May, 2001).<br> 7. B. S. Hansson, M. Knaden, S. Sachse, M. C. Stensmyr, D. Wicher, Chemoecology20, 51 (Jun, 2010).<p> This project was supported by the Max Planck Society<hr> <p class="style16">58<br> <br>Alexandra Tobler and Pelin Volkan</p> <p>Biology Department, Duke University, Durham NC 27708 USA<br> <br><a href="mailto:alexandra.tobler@duke.edu"> alexandra.tobler@duke.edu</a></p> <p class="style17">Developmental analysis of the CO<sub>2</sub> circuitry in flies and mosquitoes</p> <p>Insects respond to CO<sub>2</sub> by eliciting a wide variety of behavioral responses. While mosquitoes are attracted to CO<sub>2</sub> and use this cue to find a human host, flies, are repelled by CO<sub>2</sub> and use this cue as a warning signal. It has been shown that the receptors responsible for detecting CO<sub>2</sub> have been conserved between flies and mosquitoes. Therefore, the marked difference in response to CO<sub>2</sub> is not a result of the receptor itself, but is likely to be downstream of the odor-receptor interaction such as differences in the localization and/or connectivity of CO<sub>2</sub> neurons. Fly CO<sub>2</sub> receptor neurons localize to the antenna and project their axons to the V-glomerulus. In contrast, mosquito CO<sub>2</sub> neurons localize to the maxillary palp and project to the M-glomerulus. A small micro RNA, miR-279, has been shown to be necessary for the proper localization of CO<sub>2</sub> neurons in <em>Drosophila melanogaster</em>. The neuronal circuitry of <em>miR-279</em> mutant flies is intermediate between flies and mosquitoes. In <em>miR-279</em> mutant flies, CO<sub>2</sub> neurons localize to both the antenna and the maxillary palp and innervate both V and M glomeruli. We hypothesize that the anatomical differences of the CO<sub>2</sub> circuitry correlate with the differential behavioral response to CO<sub>2</sub>. I will test this by generating a mosquito-like wiring in the fly; I will replace the odor receptors from maxillary palps neurons (OR59c) with the CO<sub>2</sub> receptors (GR21a/GR63a), using homologues recombination. If our hypothesis is correct, we expect flies that mimic mosquito CO<sub>2</sub> neuron connectivity to display the mosquito-like CO2 attractive behavior. This study will determine whether flies that express CO<sub>2</sub> receptors in the maxillary palps display attractive or repellent behaviors, and shed light on the neuro-developmental basis of insect behavior.</p> <hr> <p class="style16">59<br> <br>Fotini Koutroumpa<sup>1</sup>, Emmanuelle Jaquin-Joly<sup>2</sup>, Jurgen Krieger<sup>3</sup>, Bill Hansson<sup>4</sup>, Teun Dekker<sup>5</sup><br></p> <p>1 Max Planck Institute for Chemical Ecology, Department of Entomology, 07745 Jena, Germany <br> 2 UMR 1272 INRA UPMC, Physiologie de l'Insecte - Signalisation et Communication, 78026 Versailles Cedex, France<br> 3 University of Hohenheim, Institute of Physiology, 70599 Stuttgart, Germany<br> 4 Max Planck Institute for Chemical Ecology, Department of Neuroethology, 07745 Jena, Germany <br 5 Div. of Chem. Ecol., Swedish Univ. of Agric. Sci., PO Box 44, SE-230 53, Sweden<br> <br><a href="mailto:fotini.koutroumpa@gmail.com"> fotini.koutroumpa@gmail.com</a> </p> <p class="style17"> OR identification and characterisation in the Ostrinia nubilalis taxon complex </p> <p>The European Corn Borer <em>Ostrinia nubilalis</em> (Lepidoptera Pyralidae) is a important pest in Europe and the US. Two pheromone strains exist, which produce and prefer opposite ratios of the two pheromone components (E11 and Z11-tetradecenylacetate, henceforth E11 and Z11 respectively). Z females produce a ratio of 97:3 of E11: Z11, whereas E females produce a ratio of 1:99 of E11:Z11. Males of the Z and E strain respond with upwind flight preferentially to the pheromone blend of females of their own strain. Consequently, in sympatry the strains do not freely interbreed. Hybrids produce and prefer intermediate ratios. Genetic studies indicate that the female sex pheromone production is oligogenic and autosomally controlled, whereas the male sensory setup is controlled by a single autosomal gene, or a group of tightly linked genes.<p> Over the last three years, we elucidated where in the olfactory circuitry this shift in preference between the two strains is located. Using neuroanatomy in conjunction with extensive physiological recordings in the brain, we found that the switch in behavior is 1) sex-linked, and furthermore 2) is not located in the brain, but rather determined at peripheral level, the moth antenna. Apparently the antennal expression pattern of pheromone receptors has changed without affecting downstream (brain) wiring. In other words, both strains of <em>O. nubilalis</em> detect the same pheromone message, but interpret it differently. This is a mechanism that could more generally account for saltatory shifts in odor preference, niche differentiation, and, as in <em>O. nubilalis</em>, strain formation.<p> Since pheromone receptor expression underlies the radical shift in behavior, we set out to identify the pheromone receptors underlying the response to pheromones. As the antennal expression pattern of the pheromone receptors seems to be the key for elucidating the existence of the two ECB strains we use <em>in situ</em> hybridization and real time PCR (qPCR) and we aim to answer to the following questions: Are the ORs specific for a strain ? Where on the antenna are they expressed? How the expression patterns differ between the different strains? </p> <hr> <p class="style16">60<br> <br> Markus Knaden, Antonia Strutz, Jawaid Ahsan, Silke Sachse, Bill S. Hansson </p> <p>Max Planck Institute for Chemical Ecology, Hans-Knöll Straße 8, 07749 Jena, Germany<br><a href="mailto:mknaden@ice.mpg.de"> mknaden@ice.mpg.de</a> <br> </p> <p class="style17"> Spatial representation of odour valence in an insect brain </p> <p>Brains have to decide whether and how to respond to detected stimuli based on complex sensory input. The fruit fly <em>Drosophila melanogaster</em> evaluates food sources based on olfactory cues. Here we performed a behavioural screen using Drosophila and established the innate valence of 110 odours. Our analysis of neuronal activation patterns evoked by attractive and aversive odours suggests that the representation of odour valence is formed at the output level of the antennal lobe. The topographical clustering within the antennal lobe of aversive-specific output neurons resembles a corresponding domain in the olfactory bulb of mice. The basal anatomical structure of the olfactory circuit between insects and vertebrates is known to be similar; our study suggests that the representation of odour valence is as well.<p> This project was supported by the Max Planck Society <hr> <p class="style16"> 61 <br> <br>Keshava Mysore, Heinrich Reichert</p> <p>Biozentrum, University of Basel, Klinglebergstrasse 50, CH-4056 Basel, Switzerland.<br><a href="mailto:keshava.mysore@unibas.ch"> keshava.mysore@unibas.ch</a> </p> <p class="style17">Olfactory lobe development in yellow fever mosquito <em>Aedes aegypti</em>: An immunocytochemical analyses.</p> <p>Considerable effort has been directed towards understanding the organization and function of peripheral and central nervous system of disease vector mosquitoes such as <em>Aedes aegypti</em>. However, to date all of these investigations have been carried out on the adult, and no studies have been undertaken to understand the development of the nervous system in mosquitoes. Here we screen a set of 30 antibodies, which have been used to study brain development in <em>Drosophila</em>, and identify 14 of these that cross-react and label epitopes in the developing brain of <em>Aedes</em>. We then use these cross-reacting antibodies in immunolabeling studies to characterize general neuroanatomical features of the developing brain in larval and pupal stages and in adult mosquitoes. Furthermore, we use immunolabeling to document the development of specific components of the <em>Aedes</em> brain, namely the antennal lobe. Our studies reveal prominent differences in the developing brain in the larval stage as compared to the pupal (and adult) stage of <em>Aedes</em>. They also uncover interesting similarities and marked differences in brain development of <em>Aedes</em> as compared to <em>Drosophila</em>. Taken together, this investigation forms a basis for future cellular and molecular investigations of brain development in the important disease vector.<hr> <p class="style16"> 62 <br> <br>Tetsutaro Hiraguchi, Toru Maeda, Mamiko Ozaki</p> <p>Grad. Sch. Sci., Kobe Univ., Kobe 657-8501, Japan<br> <br><a href="mailto:steel1515@gmail.com"> steel1515@gmail.com</a></p> <p class="style17">Unilateral integration of taste and olfactory signs enhancing feeding behavior of the blowfly, <em>Phormia regina</em>.</p> <p>Insects have well developed chemosensory system to adapt themselves to various environments. In many species, chemosensory information is investensable for proper feeding behavior. Gustatory systems is required to elicit appropriate motor pattern in fly feeding behavior. Proboscis extension response (PER) is one of the famous motor patterns in feeding behavior that is generally modified by the chemical cues from the antennae. And such main olfactory information is generally transmitted into the primary olfactory processing center, antennal lobe in the fly. However, the behavioral experiment showed that they detect palatable chemical signals increasing their appetite by other sensory pathway in blowfly, <em>Phormia regina</em> (cf. poster of Toru Maeda et al). <em>P. regina</em>detected the aversive odor by antennae. And we could observe their maxillary palps set in standing position during PER Therefore, we investigated What do their maxillary palps detect during feeding. First, we tested whether they could detect favorite odor of 1-octen-3-ol by maxillary palps even after they are starved sufficiently in behavioral experiments. Our results showed that maxillary palps worked as the appetitive odor detector in feeding behavior. In the next step, we investigated whether the olfactory and gustatory signals from both sides are creative for feeding behavior. The ipsi lateral antennae to sucrose-stimulated labellum ablated animals could not response to the aversive odor and the ipsi lateral maxillary palps ablated animals ignored the appetitive odor. These results imply that the olfactory signals could not pass into contra-lateral hemi sphere smoothly. The sub-esophageal ganglion (SEG) is the primary gustatory information processing center in the <em>P. regina</em>. We also investigated about the neural pathways between olfactory and gustatory morphologically. The palpal nerve projected into the SEG unilaterally. Our results suggest that multi modal sensory signals integrate in SEG.<hr> <p class="style16"> 63 <br> <br>Hui-Jie Zhang<sup>1,3</sup>, Alisha R. Anderson<sup>2,3</sup>, Stephen C. Trowell<sup>2,3</sup>, A-Rong Luo<sup>3</sup>, Zhong-Huai Xiang<sup>1</sup>, Qing-You Xia<sup>1,4</sup></p> <p>1 The Key Sericultural Laboratory of Agricultural Ministry, Southwest University, Chongqing 400715, China 2CSIRO Food Futures Flagship<br> 3CSIRO Ecosystem Sciences, GPO Box 1700, Canberra, ACT 2601, Australia<br> 4Institute of Agronomy and Life Science, Chongqing University, Chongqing 400044, China<br> <br><a href="mailto:alisha.anderson@csiro.au"> alisha.anderson@csiro.au</a></p> <p class="style17">Functional analysis of BmGr8, a Bombyx mori gustatory receptor</p> <p>Insect gustatory receptors (GRs) have been classified into "sugar" and "bitter" clades based on their homologies with identified receptors from <em>Drosophila</em>. Against this background the first fully sequenced lepidopteran genome of <em>Bombyx mori</em>, encodes five putative sugar receptors and a large number of putative bitter receptors. Despite almost 60 putative sugar GRs being identified from insects, ligands have only been assigned to a few of the <em>Drosophila</em> receptors. In this study, the total number of identified gustatory receptors in <em>B. mori</em> was expanded from 65 to 69. BmGr8, a silkmoth gustatory receptor from the sugar receptor subfamily, was expressed in insect cells and functionally analysed using a modified calcium imaging assay. We show that BmGr8 functions independently in <em>Sf9</em> cells and responds in a concentration-dependent manner to its ligand. The selectivity of BmGr8 responses is consistent with the known responses of one of the gustatory receptor neurons in the lateral styloconic sensilla of <em>B. mori</em>.<hr> <p class="style16"> 64 <br> <br>Mani Ramaswami</p> <p> Smurfit Institute of Genetics and Trinity College Institute for Neuroscience Lloyd Building, Trinity College, Dublin -2, Ireland <br> (Adjunct) University of Arizona, Tucson, AZ 85721 USA<br> (Adjunct) National Centre for Biological Sciences, TIFR Centre, Bangalore, India.<br> <br><a href="mailto:mani.ramaswami@tcd.ie"> mani.ramaswami@tcd.ie</a></p> <p class="style17">Mechanisms of olfactory habituation</p> <p>We have used the <em>Drosophila</em> olfactory system as a model in which to study circuit mechanisms of habituation, as well as underlying processes of long- and short-term synaptic plasticity. I will present evidence that habituation arises from potentiation of inhibitory transmission within a circuit module commonly repeated in the nervous system. In <em>Drosophila</em>, prior odorant exposure results in a selective reduction of response to this odorant. Both short-term (STH) and long-term (LTH) forms of olfactory habituation require function of the rutabaga-encoded adenylate cyclase in multiglomerular local interneurons (LNs) that mediate GABAergic inhibition in the antennal lobe; LTH additionally requires function of the CREB2 transcription factor in LNs. The odorant-selectivity of STH and LTH is mirrored by requirement for NMDA-receptors and GABAA receptors in odorant-selective, glomerulus-specific projection neurons (PNs); odorant specific LTH is specifically dependent on as components of the miRNA machinery in glomerulus-specific PNs. The need for the vesicular glutamate transporter in LNs indicates that a subset of these GABAergic neurons also release glutamate. LTH is associated with a reduction of odorant-evoked calcium fluxes in PNs as well as growth of the respective odorant-responsive glomeruli. These cellular changes use similar mechanisms to those required for behavioral habituation. Taken together with the observation that enhancement of GABAergic transmission is sufficient to attenuate olfactory behavior, these data indicate that habituation arises from glomerulus-selective potentiation of inhibitory synapses in the antennal lobe. It is possible that that similar circuit mechanisms for habituation operate in other species and sensory systems. <br> <p>Key Contributers: Trinity College Dublin: Eimear Holohan, Adrian Dervan, Aoife Larkin, Jens Hillebrand, Cathal McCann, John Lee NCBS, Bangalore: Sudeshna Das, P.S. Indulekha, K.S. Madhumala, Pushkar Paranjpe, Veronica Rodrigues, Tucson: Roy Parker Others: Jing Wang, Kei Ito, Subhabrata Sanyal.<hr> <p class="style16"> 65<br> <br>CJ Kleineidam<sup>1</sup>, M Nagel<sup>1</sup>, M Ruchty<sup>2</sup></p> <p>1 University of Konstanz, Germany<br> 2 University of Zürich, Swizerland<br> <br><a href="mailto:Christoph.Kleineidam@uni-konstanz.de"> Christoph.Kleineidam@uni-konstanz.de</a><br></p> <p class="style17">Sensing temperature is of paramount importance for social insects.</p> <p> With their ability to control the microclimate in their nests and to care for their brood, information about ambient temperature and infrared radiation is used ultimately to optimize brood development.<br> <p>We described three different types of temperature sensitive neurons that are associated with two types of peg-in-pit sensilla on the antennae (S. coeloconica & S. coelocapitula). One receptor neuron type is extremely sensitive to temperature transients (TT-neuron), another one function like a thermometer (TM-neuron) and the third one responds like a switch at the preferred brood temperature (TS-neuron). Within the AL, we found responses to temperature in many glomeruli, and so far we identified the target glomerulus of the TT-neuron.<br> <p>Currently, we explore possible modulation of the sensory neurons that correspond to adaptive changes in temperature-guided behaviors of ants, and we started to investigate how information about temperature is integrated in the first  olfactory neuropil, the AL of insects.<br> <p>Ruchty M, Helmchen F, Wehner R, Kleineidam CJ (2010) Representation of thermal information in the antennal lobe of leaf-cutting ants. Frontiers in Behavioral Neuroscience 4: 174. Ruchty M, Roces F, Kleineidam CJ (2010) Detection of Minute Temperature Transients by Thermosensitive Neurons in Ants. Journal of Neurophysiology 104: 1249 1256.<br> Ruchty M, Romani R, Kuebler LS, Roces F, Isidoro N, Kleineidam CJ (2009) The thermo-sensitive sensilla coeloconica of leaf-cutting ants (<em>Atta vollenweideri</em>). Arthropod Structure & Development 38: 195-205.<hr> <p class="style16"> 65<br> <br>Brian H. Smith<sup>1</sup>, Martin Strube-Bloss<sup>1,2</sup></p> <p>1 School of Life Sciences, PO Box874501, Arizona State University, Tempe, AZ 85287<br> 2 Current address: Max Planck Institute for Chem. Ecol., Dep. of Evol. Neuroethol. Hans-Knoell-Strasse 8, D-07745 Jena, Germany<br> <br><a href="mailto:brianhsmith@asu.edu"> brianhsmith@asu.edu</a></p> <p class="style17">Distributed plasticity in the insect olfactory system: some conceptual problems and possible solutions</p> <p>Many studies have now shown conclusively that processing information about odors in the neural networks of the Antennal Lobe is not static. Rather this processing is sensitive to the context in which an odor is presented. We have now demonstrated both associative and non-associative plasticity in the honey bee AL. When an odor is associated in the context of sucrose reinforcement, the spatiotemporal pattern in the AL that represents this odor becomes more distinct from other odors (Fernandez et al 2009). Furthermore, when an odor (X) is explicitly not associated with reinforcement, a mixture of X with another (AX) becomes more like  A (Locatelli et al submitted). These types of plasticity appear also in the mammalian Olfactory Bulb, which suggests that plasticity reflects fundamental qualities of neural networks in early olfactory processing. However, the existence of plasticity in early processing presents a problem in our understanding of how plasticity works in distributed areas of the brain that respond to the same contextual information. It implies that the sensory pattern output across Projection Neurons of the AL changes slightly every time an odor is associated, or not associated, with reinforcement. How then can the next levels of processing that are also involved in forming memories about this pattern, for example, the Mushroom Bodies,  track the changing pattern from the AL? To address this issue, we have begun multichannel electrophysiological recordings from the PN output of the AL and from the Extrinsic Neurons that provide output from the MB. We perform these recordings under conditions of associative and nonassociative conditioning. To date we have surprising findings about the speed of classification of odors by the AL and MB neuropils. This speed, combined with recent anatomical studies of the MB outputs are we record from, suggests an interesting possible role for early plasticity in the AL.</p> <p>Supported by awards to BH Smith from NIH-NCRR (RR014166), NIH-NIDCD (DC011422) and the Office of Naval Research.</p> <p>Fernandez PC, Locatelli FF, Rennell N, Deleo G, Smith BH. (2009) J Neuroscience 29: 10191-10202.<hr> <p class="style16"> 66<br> <br>Amelie Baschwitz, Antonia Strutz, Veit Grabe, Bill S. Hansson & Silke Sachse</p> <p>Max Planck Institute for Chemical Ecology, Department of Evolutionary Neuroethology, Jena, Germany<br> <br><a href="mailto:abaschwitz@ice.mpg.de"> abaschwitz@ice.mpg.de</a></p> <p class="style17">Morphological characterization of inhibitory projection neurons in the Drosophila olfactory system</p> <p>In the olfactory system of the fruit fly <em>Drosophila</em> odor stimuli are transferred from the antenna to the corresponding glomerulus in the antennal lobe (AL) by olfactory sensory neurons. Within the AL, the sensory neurons synapse onto projection neurons (PNs), which innervate higher brain centers like the mushroom bodies, the ventro-lateral protocerebrum and the lateral horn. Most PNs are uniglomerular and excitatory. However, one population of PNs is multiglomerular and shows in anti-GABA immunostaining an increasing number of GABAergic PNs dependent on the age of the fly. For further anatomical characterization of these inhibitory PNs we used photoactivatable GFP (PA-GFP). This method enables labeling of single neurons by activation of single somata or labeling of all inhibitory PNs innervating a specific glomerulus. First results show that the illumination of a specific glomerulus displays a merely oligoglomerular innervation pattern for most of the inhibitory PNs analyzed.<hr> <p class="style16"> 67<br> <br>Jonas Barth, Moritz Hermann, André Fiala</p> <p>Georg-August-University Göttingen, Johann-Friedrich-Institute for Zoology and Anthropology, Dept. Molecular Neurobiology of Behaviour<br> <br><a href="mailto:jbarth2@gwdg.de"> jbarth2@gwdg.de</a></p> <p class="style17">Discrimination and Generalisation in Olfactory Learning of <em>Drosophila melanogaster</em></p> <p>In associative learning animals can connect sensory stimuli with a reward or a punishment. Thereby, the animal learns to predict the consequences of a specific sensory stimulus. A fruit fly, for example, can associate an odour with a punishing electric shock. However, the animal has to evaluate the sensory input and act accordingly, also if the stimulus is slightly different than the learned stimulus. Thus, the fly has to be able to react to similar odours with a learned response (generalization). However, similar stimuli might have different consequences depending on the learning procedure. Therefore, the animal has to be able to differentiate between similar stimuli, that have been learned differentially (discrimination learning).<p> The fruit fly <em>Drosophila melanogaster</em> is a suitable model system to study generalization and discrimination of sensory stimuli as the flies are capable of olfactory learning. If an odour (conditioned stimulus, CS) is presented to the flies and paired with an electric shock (unconditioned stimulus, US), they will learn to avoid this odour when tested in a T-maze situation. Usually, a subset of monomolecular odours is used for olfactory learning (e.g. Methylcyclohexanol or 3-Octanol). In a discriminative learning procedure, the fly is encountered with two different odours, one is paired with the electric shock (CS+) and the other is not (CS-). In the subsequent T-maze test, the flies can decide to approach or avoid the CS- or CS+. A generalisation effect can be observed, if flies are trained with an odour CS1 and tested with another odour CS2. If the flies generalize between the two odours, they do not show a different behaviour towards the two odours. Experiments were performed in our lab to test the generalization of two distinct but structurally similar odours. In addition, it was tested whether the odours can be distinguished by the flies if they are trained in a discriminative way (one odour is CS+, the other CS-).<p> Our results show that for similar odourants generalization and discrimination can be achieved depending on the training protocol and test situation. In vivo calcium imaging was used to investigate the underlying neuronal structures and mechanisms.<p> This work is funded by the DFG via the SPP 1392  Integrative Analysis of Olfaction .<hr> <p class="style16"> 68<br> <br>Alexandra Guigue<sup>1</sup>, Frédéric Marion-Poll <sup>1,2</sup></p> <p>1 INRA Centre de Versailles-Grignon, UMR 1272 PISC, route de Saint-Cyr, 78026 Versailles, France<br> 2 AgroParisTech, Département Sciences de la Vie et Santé, UFR EAI, 16 rue Claude Bernard, 75321 Paris, France<br> <br> <a href="mailto:alexandra.guigue@versailles.inra.fr"> alexandra.guigue@versailles.inra.fr</a></p> <p class="style17"><em>Drosophila</em> detects starch quickly despite of it being tasteless</p> <p>Starch is a polymer of glucose commonly found in the diet of <em>Drosophila melanogaster</em> when reared in the laboratory. Although starch is tasteless, flies might be able to adjust their feeding according to the caloric reward associated to its ingestion. In this work, we evaluated how fast this process can take place. Using a binary food choice assay (Tanimura et al., 1982), we found that starch alone (3%) is not consumed by flies in a two-hour test. Interestingly, when starch is mixed with fructose (35mM), patches of fructose associated with starch were preferred over patches of fructose-only. This suggests that starch-enriched food patches become sweeter than fructose-only patches in relation to the feeding activities of the flies, which might induce a partial digestion of starch. In order to test this hypothesis, we added an ±-amylase competitive inhibitor, ±-cyclodextrin, in the food patches to prevent starch from being transformed by this enzyme. ±-cyclodextrin completely abolished the preference towards starch-enriched food patches. Interestingly, this synergistic effect did not happen when soluble starch was added to a fructose solution using MultiCAFE experiments (Ja et al., 2007; Sellier et al., 2010). All put together, these results suggest that in addition to post-ingestive feedbacks, flies also directly monitor the suitability of a food substrate by releasing digestive enzymes that dynamically change the composition of their food.<hr> <p class="style16"> 69<br> <br>Chang Liu, Yoshinori Aso, Igor Siwanowicz, <u>Hiromu Tanimoto</U></p> <p>Max-Planck-Institut für Neurobiologie, Am Klopferspitz 18, D-82152 Martinsried, Germany<br> <br><a href="mailto:hiromut@neuro.mpg.de"> hiromut@neuro.mpg.de</a></p> <p class="style17">Reinforcement neurons for various types of olfactory memories </p> <p>A paired presentation of an odour and electric shock induces aversive odour memory in <em>Drosophila melanogaster</em>. Electric shock reinforcement is mediated by dopaminergic neurons, and it converges with the odour signal in the mushroom body (MB). Dopamine is synthesized in ~280 neurons that form distinct cell clusters and is involved in a variety of brain functions. Each dopaminergic cluster contains multiple types of dopaminergic neurons with different projections and physiological characteristics. Functional understanding of the circuit for aversive reinforcement and memory, therefore, requires cellular identification. Here we identified different types of dopaminergic neurons essential for signalling punishment of the electric shock. Since these neurons terminate in the restricted part of the mushroom body, the synapses undergoing associative plasticity are localized along the axonal trajectory of the Kenyon cells.<hr> <p class="style16"> 70<br> <br>Ali Salloum<sup>1</sup>, Violaine Colson<sup>1</sup> and <u>Frédéric Marion-Poll</u><sup>1,2</sup></p> <p>1 UMR INRA-UPMC, Physiologie de l Insecte: Signalisation et Communication, INRA Centre de Versailles, 78026 Versailles, France<br> 2 AgroParisTech, Département Sciences de la Vie et Santé, 16 rue Claude Bernard, 75231 Paris 05, France<br> <br><a href="mailto:frederic.marion-poll@versailles.inra.fr"> frederic.marion-poll@versailles.inra.fr</a></p> <p class="style17">Appetitive and aversive learning in <em>Spodoptera littoralis</em> larvae.</p> <p>Larval Lepidoptera have limited foraging capabilities and usually depend on adults as concerns their food choices. However, they can express orientation and feeding choices and these choices may involve associative learning. We tested if <em>Spodoptera littoralis</em> larvae can learn to associate an odor with a tastant using a new classical conditioning paradigm. Groups of larvae were exposed to an unconditioned stimulus (US: fructose or quinine mixed with agar) paired with a conditioned stimulus (CS: hexanol, geraniol or pentyl acetate) in a petri dish. Their reaction to CS was subsequently tested in a petri dish at different time intervals after conditioning. Trained larvae showed a significant preference or avoidance to CS when paired with US depending on the reinforcer used. The training was more efficient when larvae were given a choice between an area where CS US was paired and an area with no CS (or another odor). In these conditions, the memory formed could be recalled at least 24 h after pairing with an aversive stimulus and only 5 min after pairing with an appetitive stimulus. This learning was specific to CS because trained larvae were able to discriminate CS from another odor that was present during the training but unrewarded. These results suggest that Lepidoptera larvae exhibit more behavioral plasticity than previously appreciated.<br> Supported by a grant from the Syrian government to AS.<hr> <p class="style16"> 71<br> <br>Nicholas Strausfeld<sup>1</sup>, Kei Ito<sup>2</sup>, Jonathan Bacon<sup>3</sup> and Laiyong Mu<sup>1</sup></p> <p>1 Department of Neuroscience, University of Arizona, Tucson, AZ, United States.<br> 2 Center for Bioinformatics, Institute of Molecular and Cellular Biosciences, University of Tokyo, Tokyo, Japan.<br> 3 School of Life Sciences, University of Sussex, Brighton, United Kingdom.<br> <br><a href="mailto:flybrain@neurobio.arizona.edu"> flybrain@neurobio.arizona.edu</a></p> <p class="style17">Reconstructing the World: Common Organization and Function in Olfactory and Visual Systems.</p> <p>In insects, axons from olfactory receptor neurons sharing the same receptor protein identity converge to a defined antennal lobe glomerulus. This arrangement is considered special to the antennal lobes, but it is not unique. Glomerular domains exist in each segmental ganglion, where they receive converging axons relaying from specific sets of receptors. Local interneurons refine and integrate these incoming signals and relay higher order information to projection neurons, as occurs in the antennal lobe.<p> Likewise, in the visual system unique ensembles of outputs from deep levels of the optic lobes (the lobula complex) segregate their axons to the protocerebrum to supply a system of glomeruli that is the segmental homologue of the antennal lobe. In the optic glomerular complex, local interneurons establish reliable downstream responses by signal averaging unreliable inputs from isomorphic populations of relay neurons from the lobula complex. In an optic glomerulus, local interneurons are tuned to the same specific stimuli that evoke responses in the cognate clone of input neurons. Local interneuron responses are noise-free, and disambiguate information from synaptic noise generated peripherally within the lobula. This information is relayed to projection neurons: premotor descending neurons and relays that reach higher center in the brain.<p> This glomerular organization in the deep visual system is functionally comparable to the organization of converging olfactory sensory neurons to antennal lobe glomeruli, where noisy signals from olfactory receptor neurons are refined through interactions among glomeruli via local interneurons. In short, the optic glomerular complex and antennal lobes share the same principle anatomical and functional organization in serving the similar function of refining and integrating incoming signals and thereby contributing to the reconstruction of their relevant sensory worlds.<hr> <p class="style16"> 72<br> <br>Fernando F. Locatelli<sup>2</sup>, Patricia C. Fernandez <sup>3</sup>, Anna Yoshihiro<sup>1</sup>, Brian H Smith <sup>1</sup></p> <p>1 School of Life Sciences, Arizona State University, AZ, USA. <br> 2 Laboratorio de Neurobiología de la Memoria, IFIByNE, UBA-CONICET, Buenos Aires, Argentina.<br> 3 EEA Delta del Paraná, and Cátedra de Biomoléculas, Facultad de Agronomía, UBA, Buenos Aires, Argentina.<br><br><a href="mailto:locatellif@yahoo.com.ar"> locatellif@yahoo.com.ar</a>; <a href="mailto:pcfernan@agro.uba.ar"> pcfernan@agro.uba.ar</a></p> <p class="style17">Discrimination learning of floral odors induces plasticity in the antennal lobe</p> <p>Floral odors are highly variable combinations of several volatiles. Composition analysis shows that no two flowers are exactly alike, even examples from the same species and cultivar. In this context, pollinators must establish if a newly encountered flower is similar or different enough to a previous rewarded one, turning foraging decisions into a fine tuned generalization-discrimination task. Sensory coding must provide mechanisms for precise odor recognition, allowing perceptual stability (i.e. generalization to prevent all experiences from being independent and novel) [1]. We hypothesize that experience with odors tunes sensory processing in the antennal lobe and thereby permit odor recognition and classification of newly encountered flowers [2]. In the present work we designed artificial floral blends that mimic the components, proportions and variability of 2 natural varieties of snapdragon flowers. All designed blends share the same components. But they could be differentiated based on the relative concentration of the components, which were more similar within than between cultivars. We trained restrained honey bees using the proboscis extension response paradigm (PER). Bees were differentially conditioned using examples of both cultivars. After training we tested the bees with a new example from each cultivar that was not used during training. The duration of the PER was lower and the latency longer when an example of the non-rewarded cultivar was offered to the trained bee. Odor induced activity patterns were measured in Projection Neurons of the Antennal Lobe by calcium imaging. Consistent with behavior, results suggest that the neural network in the AL was tuned by the experience to decorrelate mixtures representing different floral varieties. Experience-dependent plasticity at the level of the Antennal Lobe may help animals categorize a newly flower as belonging to a class related to reinforcement. This kind of mechanism may allow bees a quick adaptation to a different and constantly changing environment.<br><br>[1] Barnes et al 2008. Nat Neurosci 11(12):1378-1380<br> [2] Fernandez et al 2009. J Neurosci 29(33):10191-10202<hr> <p class="style16"> 73<br> <br>Veit Grabe, Martin Strube-Bloss, Bill S. Hansson and Silke Sachse</p> <p>Max-Planck-Institute for Chemical Ecology, Hans-Knöll-Straße 8, 07745 Jena, GERMANY<br><br><a href="mailto:vgrabe@ice.mpg.de"> vgrabe@ice.mpg.de</a></p> <p class="style17">The impact of local interneurons on the odor-evoked activity patterns in the antennal lobe of <em>Drosophila melanogaster</em></p> <p>The olfactory environment of a fruit fly is consisting of a wide variety of odors which are detected by a diverse set of odorant receptors (OR) and processed by a complex neuronal network in the first olfactory neuropile, the antennal lobe (AL). It is assumed that local interneurons (LN) are involved in the processing mechanism of olfactory information at the level of the AL. It has been shown that the different neuronal populations within the AL are connected by diverse chemical as well as electrical synapses. In order to analyze how this network is processing the incoming olfactory information from the sensory neurons, we are examining the influence of the different LN populations onto the odor-evoked activity patterns. To do so, we are expressing the temperature-sensitive UAS-shibirets to inactivate the synaptic transmission from LNs to other neurons in the AL. With this genetic background we are functionally imaging the sensory as well as the projection neurons using G-CaMP1.6 to analyze if and how the activity patterns to specific odors are modified. We are also planning to study the behavioral consequences after silencing different LN populations. <p>This work is supported by the BMBF and the Max Planck Society.<hr> <p class="style16"> 74<br> <br>Silke Sachse, Veit Grabe, Antonia Strutz, Marco Schubert, Bill S. Hansson</p> <p>Max-Planck-Institute for Chemical Ecology, Hans-Knöll-Straße 8, 07745 Jena, GERMANY<br><br><a href="mailto:ssachse@ice.mpg.de"> ssachse@ice.mpg.de</a></p> <p class="style17">Encoding and processing of olfactory information in neural circuits </p> <p>We are investigating how odors are coded and processed in the <em>Drosophila</em> brain to lead to a specific odor perception. The basic layout of the first olfactory processing centers, the olfactory bulb in vertebrates and the antennal lobe (AL) in insects, is remarkably similar. Odors are encoded by specific ensembles of activated glomeruli (the structural and functional units of the bulb-lobe) in a combinatorial manner. The vinegar fly <em>Drosophila melanogaster</em> provides an attractive model organism for studying olfaction, as it allows genetic, molecular and physiological analyses. We are performing calcium as well as chloride imaging to decipher basic principles involved in olfactory transduction, coding, processing and perception of odors. We will present our recent insights into olfactory coding strategies yielded by morphological and functional analysis of the different neuronal populations, i.e. sensory neurons, local interneurons and projections neurons, present in the <em>Drosophila</em> antennal lobe.<hr> <p class="style16"> 75<br> <br>Jonas Barth and <u>André Fiala</u> </p> <p>Georg-August-Universität Göttingen, Molecular Neurobiology of Behavior, Grisebachstr. 5, 37077 Göttingen, Germany<br><br><a href="mailto:afiala@gwdg.de"> afiala@gwdg.de</a></p> <p class="style17">Odor generalization and discrimination learning in <em>Drosophila</em></p> <p>Many animals are able to differentiate a large variety of odors with respect to their chemical identity and concentration. We have asked how different odor identities are represented in the brain of the fruit fly <em>Drosophila melanogaster</em> at two levels of processing: at olfactory sensory neurons and at olfactory projection neurons within the fly s antennal lobes. To this end, we have used the genetically encoded, FRET-based calcium sensor Cameleon 2.1 because of the minimization of movement artefacts due to its ratiometric properties, a good signal-to-noise ratio and high fluorescence intensity in the non-activated state. We find that odor-evoked activity patterns differ in terms of their similarity when olfactory sensory neurons and projection neurons are compared, as revealed by principal component analysis performed by Dr. Marc Timme s group. Interestingly, an odor pair that evokes clearly different calcium activity patterns at the level of sensory neurons appears to evoke very similar activity patterns at the level of second order projection neurons. These results correlate with behavioural learning experiments performed in Prof. Bertram Gerber s group showing that this odor pair is strongly generalized. We propose that olfactory computation within the antennal lobe might not only cause a fine discrimination of odors but can also cause a convergence of odor information from separated input channels into distinct classes. We therefore investigate whether or not such a classification mechanism might be subject to learning-dependent modulation. In particular, we investigate whether structurally similar odors can be better discriminated by fruit flies after a differential training procedure. We find that if flies are trained to associate an odor with electric shocks the response is generalized across a different, but similar odor. However, if flies are differentially trained the degree of generalization decreases. Implications for possible physiological mechanisms will be discussed.<hr> <p class="style16"> 76<br> <br>Xin-Cheng Zhao<sup>1</sup>, Pål Kvello<sup>2</sup>, Bjarte Bye Løfaldli<sup>2</sup>, Hanna Mustaparta<sup>2</sup>, Bente G. Berg<sup>1</sup></p> <p>1 Dept. of Psych., Norwegian University of Science and Technology, Trondheim, Norway,<br> 2 Dept. of Biology, Norwegian University of Science and Technology, Trondheim, Norway<br> <br><a href="mailto:xin cheng.zhao@samfunn.ntnu.no"> xin cheng.zhao@samfunn.ntnu.no</a></p> <p class="style17">Representation of pheromones and plant odors in protocerebral regions of the male heliothine moth</p> <p>The male-specific olfactory pathway of moths offers the opportunity of investigating a neural network that is relatively simple and at the same time of considerable importance for preservation of the species. In heliothine moths, the male-specific system is activated by three to four odor stimuli, each of which is detected by a group of receptor neurons converging onto an easily identifiable glomerulus in the primary olfactory center of the brain. This arrangement is linked to two well-defined and opposite behavioural responses, sexual attraction versus interruption of attraction. The numerous ordinary glomeruli, which receive input from receptor neurons detecting plant odors, seem to be equivalent to the system described in females. As compared to the relatively well explored chemotopic organization characterizing the first synaptic level of the olfactory pathway, less is known about the encoding principles residing within the higher olfactory centres. In the present study, we have made a standard model of the male <em>Heliothis virescens </em>brain and brought reconstructed projection neurons of distinct physiological categories into this common reference framework for the purpose of visualizing how odor signals, including pheromones and plant odors, are represented in the protocerebral regions.<br> <br>This work was supported by the Norwegian Research Council, project no. 1141434, and the Royal Norwegian Society of Sciences and Letters.<hr> <p class="style16"> 77<br> <br>Sonja Bisch-Knaden, Yuki Sugimoto, Christine Mißbach, Silke Sachse, Bill S. Hansson</p> <p>Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, Jena, Germany<br> <br><a href="mailto: sbisch-knaden@ice.mpg.de"> sbisch-knaden@ice.mpg.de</a></p> <p class="style17">Impact of domestication on the olfactory system of the silk moth <em>Bombyx mori</em></p> <p>The domestication of the silk moth <em>Bombyx mori</em> started five thousand years ago with the purpose to produce high amounts of silk. <em>B. mori</em> is now completely dependent on human care and not able to survive in nature. Because of their nocturnal life lifestyle, female silk moths originally had to locate host plants for oviposition mainly by olfactory cues. We asked which impact domestication had on the olfactory system of B. mori by comparing it with that of its wild ancestor <em>B. mandarina</em>. We used several experimental approaches to analyze anatomical as well as functional modifications (brain reconstructions, electroantennogram recordings, optical imaging) and found the following differences in <em>B. mori</em> as compared to <em>B. mandarina</em>: i) the number of olfactory glomeruli was lower and more variable between individuals; ii) the latency and the duration of the odour response was delayed and prolonged, respectively, both at the level of the antenna and within the antennal lobe, the first olfactory neuropil; iii) odour-evoked activity patterns in the antennal lobe were more variable between individuals; iv) odour representations for different odours were less odour-specific. We conclude that in the course of domestication, the olfactory system of the female silk moth underwent essential changes, reflecting the absent selection pressure on detection and discrimination of plant-derived volatiles. Although <em>B. mori</em> has become a model insect for investigations of pheromone detection and processing in males, the olfactory coding of non-pheromonal odours seems to be degraded, at least in female <em>B. mori</em>. This fact should therefore be taken into consideration when conclusions regarding olfactory physiology and morphology in this species are drawn.<hr> <p class="style16"> 78<br> <br>Kristina M. Gonzalez<sup>1</sup>, Gregory C.H. Chua<sup>1</sup>, Marie-Jeanne Sellier<sup>2</sup>, Todd P. Livdahl<sup>1</sup>, Frederic Marion-Poll<sup>2</sup>, <u>Linda M. Kennedy</u><sup>1</sup></p> <p>1 Dept of Biology, Clark University, Worcester, MA 01602 USA<br> 2 INRA UMR INRA-Universite Pierre et Marie Curie no 1272, Physiologie de l Insecte: Signalization et Communication, route de Saint Cyr, 78026 Versailles Cedex, France<br> <br><a href="mailto:lkennedy@clarku.edu"> lkennedy@clarku.edu</a></p> <p class="style17">Experience induced changes in Drosophila sugar taste sensitivity take place in or before the sugar taste receptor cell</p> <p>Experience with sweeteners increases psychophysical taste sensitivities for sugars and MSG in humans, and behavioral taste sensitivities for sugars in <em>Drosophila melanogaster</em>. Human psychophysical and hamster chorda tympani data suggest a peripheral nervous system mechanism. We conducted behavioral and receptor cell neurophysiological studies in <em>D. melanogaster</em> to further explore the locus of the mechanism. Experience induced changes in taste sensitivities for sugars occurred in both Oregon R and Canton Special strains. Flies raised on a fructose based medium chose to eat significantly more glucose or fructose of mid-range concentrations than flies raised on a glucose based medium did, in both two-choice and multi-choice behavioral tests. Likewise, the sugar taste receptor cells of fructose reared flies responded to fructose or glucose of mid-range concentrations with significantly greater firing rates than the receptor cells of flies reared on glucose medium. A significant positive correlation between the behavioral and neurophysiological data suggests that at least a portion, if not all, of the changes in behavior resulted from the changes in sugar receptor cell firing. These are the first data to show that experience induced changes in taste sensitivity take place in the receptor cells of any species. They indicate a mechanism for the experience induced changes in or before the taste receptor cells.<p> KMG was supported by a NSF Graduate Research Fellowship and MJS by a PhD grant from INRA/ABIES. The work was supported by NIH NIDCD R15DC/OD02663 and R15DC009042 to LMK and Clark University research and travel funds to KMG. <p> References: Berteretche et al. (2005) Appetite 45, 324; Gonzalez (2009) Ph.D. Thesis, Clark Univ.; Gonzalez et al. (2007) Chem. Senses 33, 173; Hassan et al. (2006) Chem. Senses 31, 5; Kobayashi and Kennedy (2002) Physiol. Behavior. 75, 57<hr> <p class="style16"> 79<br> <br>Anandasankar Ray, Stephanie Turner, Sean M. Boyle</p> <p>Department of Entomology CMDB Program and GGB Program, University of California, Riverside, CA 92521, USA<br> <br><a href="anand.ray@ucr.edu "> anand.ray@ucr.edu </a></p> <p class="style17">Modification of CO<sub>2</sub>-mediated attraction in mosquitoes</p> <p>CO<sub>2</sub> present in exhaled air is one of the primary cues that female mosquitoes use to identify human hosts. The CO<sub>2</sub> receptor proteins are highly conserved amongst several haematophagus insect species and are a prime target for identification of odorants that can modulate activity and therefore modify host-seeking behavior. We have identified several classes of volatile odorant molecules that modify the response of the CO<sub>2</sub> sensitive neuron in mosquitoes including ones that efficiently inhibit the response and ones that mimic activity. Odors that can block the CO<sub>2</sub> sensitive neuron are candidates to mask host-seeking behavior, while odors that mimic activity of CO<sub>2</sub> can be used as a convenient lure in traps. These volatile odorants offer a novel approach to developing insect behavior modifying odors that target the ability to sense an important olfactory cue CO<sub>2</sub>. <hr> <p class="style16"> 80<br> <br>Zev Wisotsky<sup>1</sup>, Adriana Medina<sup>2</sup>, Erica Freeman<sup>3</sup>, and <u>Anupama Dahanukar<sup>2</sup></u></p> <p>1 Interdepartmental Neuroscience Program<br> 2 Department of Entomology<br> 3 Bioengineering Interdepartmental Graduate Program University of California, Riverside, CA 92521<br> <br><a href="anupama.dahanukar@ucr.edu "> anupama.dahanukar@ucr.edu </a></p> <p class="style17"><em>Drosophila</em> sweet receptors</p> <p>The <em>Drosophila</em> genome encodes a large family of 68 Gustatory receptors that are involved in recognition of various categories of chemicals including sweet and bitter taste compounds. In previous studies we showed that Gr5a and Gr64a, which belong to a clade of eight receptors, are sugar receptors in <em>Drosophila</em>. Other receptors belonging to this clade are also co-expressed in some Gr5a neurons, but their function is poorly understood. We are examining the functional and structural properties of this group of  sweet receptors using various genetic tools. Interestingly, one or more of the sweet receptor genes are predicted to be pseudogenized in some <em>Drosophila</em> species. We are thus comparing our electrophysiological and behavioral analyses of receptors mutants to those of various <em>Drosophila</em> species in order to determine Gr gene contribution to specific evolutionary variations in appetitive selectivity across Drosophila species. In a family-wide expression analysis of Gustatory receptors, we found molecular heterogeneity within sweet- and bitter-sensing neurons and also determined the patterns of axon termini of neurons expressing individual receptors. Currently, we are investigating the behavioral significance of discrete representation patterns of sweet neurons in the brain by combining the manipulation of subsets of sweet-sensing neurons with high-resolution feeding behavior assays. <hr> <p class="style16"> 81<br> <br>Marcus C. Stensmyr and Bill S. Hansson </p> <p> Max Planck Institute for Chemical Ecology, Department of Evolutionary Neuroethology, Hans Knöll Str. 8, 07745 Jena, Germany<br> <br><a href="mstensmyr@ice.mpg.de "> mstensmyr@ice.mpg.de </a></p> <p class="style17">Specialized noses for specialized lifestyles</p> <p>The olfactory system directly interfaces with the environment, thus, changes in the environment, or a change in an animal s habits, as e.g. niche specialization, would presumably also lead to changes in the olfactory system. Comparative studies on specialized animals, with known generalist ancestors, could hence be a way of revealing general processes shaping olfactory systems, as well as highlighting importance and function of specific chemosensory genes. In this presentation I will outline current work in our laboratory dealing with olfactory adaptations at the molecular, physiological, morphological and behavioral level.<hr> <p class="style16"> 82<br> <br>Marianna I. Zhukovskaya</p> <p>Sechenov Institute, Russian Academy of Sciences, 44 Thorez Pr. Saint-Petersburg, Russia<br> <br><a href="mzhukovskaya@yahoo.com "> mzhukovskaya@yahoo.com </a></p> <p class="style17">Antennal liquid secretions, grooming, and responses to odors in the cockroach, <em>Periplaneta americana</em></p> <p>Antennae of restrained American cockroach, <em>Periplaneta americana</em> L., accumulates a layer of clear liquid at its surface, which is significantly more pronounced in odor stimulated than non-stimulated antennae. The decline in spiking of single sensilla in response to appropriate odorant correlates with its length and presence of pores at the sensillar bases. Namely, longer sensilla without pores at the base do not alter their firing, while the shortest ones with pores at their bases show the significant drop of the responses. Freely behaving insects groom their antennae eliminating the excess of liquid with dissolved odorants. Frequency of antennal grooming increases in odor presence. Thus, the suggested role of antennal liquid secretion in olfactory responses is the non-specific removal of odor molecules from the outer surface of sensilla. <p> The study was supported by RFBR grant #09-04-01042a<hr> <p class="style16"> 83<br> <br>Vladimir D. Ivanov, Stanislav I. Melnitsky</p> <p>Department of entomology, Faculty of Biology, St. Petersburg State University, 199034 St.Petersburg, Russia<br> <br><a href="v--ivanov@yandex.ru "> v--ivanov@yandex.ru </a></p> <p class="style17">Diversity and evolution of the antennal sensilla in caddis-flies (Trichoptera)</p> <p>Caddis-flies (Trichoptera) is a sister order to the well known butterflies and moths (Lepidoptera). The antennae in Trichoptera are provided with various sensilla. Most diverse sensilla are found to be situated on the antennal flagellum. The comparative study of flagellar sensilla in 78 species belonging to 28 families of Trichoptera by optical and SEM microscopy reveals the structural diversity of the cuticular parts of sensilla. Most of these sensilla are supposed to be olfactory, although some of them are probably mechanoreceptors. Sixteen structural types of the cuticular components of sensilla are recognized in Trichoptera (Melnitsky, Ivanov, 2010, 2011; Larsson et al., 2002; Faucheux, 2004, 2005, 2006; Melnitsky, Ivanov, in press). Two major groups are recognized: the long sensilla (longer than 20 ¼m) makes the upper level of the sensory structures, whereas the short sensilla (generally less than 10 ¼m) are situate din the lower level. Several types of the trichoid, pseudotrichoid, and tongue-like sensilla are found to occur in the upper level. The structures in lower level include various types of sensilla: basiconic, placoid, styloconic, pseudostyloconic, coronar, auricillar, and diverse pseudoplacoids (mushroom-like, bilobed, dentate, and forked).<br> The flagellum in Rhyacophilidae, the most primitive of the extant Trichoptera, has the numerous trichoids in the upper level and several types of sparsely distributed lower level sensilla: basiconic, styloconic, mushroom-like and bilobed pseudoplacoids showing no specialized sensory zones or regular patterns. More advanced families usually have more numerous sensilla of the lower level. The increased number and, in several instances, the larger size of these sensilla seem to increase the sensitivity of the olfactory system and provide the advantage in male competition. There are specialized sensory zones appeared in a few families; these zones are visible as spots, stripes, depressions or projections on the ventral and ventro-lateral parts of flagellomers, mostly in the basal part of the flagellum. The sensory zones are devoid of the long trichoids so that the lower level sensilla are exposed. These zones are assumed to be the specialized areas developed for the precise and fast orientation in the variable pheromone clouds. Reduction of the antennal sensilla is found to occur in a few cases, e.g., in Leptoceridae and in some Apataniidae. Such a reduction is supported by the alteration of the mating behavior in Trichoptera. The normal mating pattern, when the male seeks the female while the female produces the attracting pheromones, requires the low population densities and sparse distribution of insects in the environment. This seeking strategy does not work in the dense populations so the opportunistic strategies should be used. Caddis-flies of the family Leptoceridae use the male swarming and visual recognition as the mating strategy; they have no female pheromones and the reduced antennal sensilla. Some species from the tribe Baicalinini (Apataniidae) either makes very large aggregations under the stones on the shores of the lake Baikal, or run on the water surface of this lake. These situations are not favorable for pheromone communication so these insects use the visual and tactile recognition, and their antennal sensilla are partly reduced. The comparative analysis suggest the antennal sensilla to be the important character in the studies of taxonomy and evolution. <br> This study has been supported by the RFFI grants ! 08-04-00295, ! 11-04-00076 and the grant from the Federal program of support for leading scientific schools NSH-3332.2010.4.<hr> <p class="style16"> 84<br>Lydia V. Zueva<sup>1</sup>, Stanislav I. Melnitsky<sup>2</sup>, and Vladimir D. Ivanov<sup>2</sup></p> <p>1 Sechenov Institute, Russian Academy of Sciences, 44 Thorez Pr. Saint-Petersburg, Russia<br> 2 Department of entomology, Faculty of Biology, St. Petersburg State University, 199034 St.Petersburg, Russia<br> <br><a href="lzueva@yahoo.com"> lzueva@yahoo.com </a></p> <p class="style17">Ultrastructure of the pseudoplacoid sensilla in Philopotamidae (Trichoptera)</p> <p>The pseudoplacoid sensilla have been found in Trichoptera and lower Lepidoptera. These sensilla are the small outgrowths situated in the lower sensory level on the antennal flagellum and the palps of the mouthparts. Structure of external cuticular parts of the pseudoplacoid sensilla in <em>Chimarra batukaua</em> Malicky, <em>Dolophilodes ornata</em> Ulmer, <em>Gunungiella gundergonia</em> Melnitsky et Ivanov, <em>Philopotamus ludificatus</em> McL., <em>Ph. montanus</em> Don., Wormaldia simplicissima Melnitsky et Ivanov from the family Philopotamidae have been studied by the optical and SEM microscopy; the internal structures were studied in Ph. montanus Don. by the optical and TEM microscopy. Structurally these sensilla consists of the cuticular part and the soft tissue. The comparative study suggests that the cuticular parts in these sensilla in the studied species are similar. The cuticular part is represented by the socket surrounded by elevated cuticular ring, and the body of the sensillum projecting from the bottom of the socket. The body has a well developed wide stalk and an enlarged head that in the studied species is similar to the mushroom cap, with concave dorsal surface and elevated margins. The dorsal surface of the sensillar head is provided with numerous radial grooves originating from the small central projection. These grooves have numerous pits distributed along them as represented on the SEM photographs, that are apparently the entrances to the pores as suggested by the studies of the cross-sections of the sensilla. The same grooves are visible on the ventral surface of the head in <em>W. simplicissima</em>. The sensillar heads are slightly elevated above the antennal surface but do not protrude beyond the microtrichia.<p> Studies of the cross sections of the antenna reveal the fine internal structure of the pseudoplacoids. Each pseudoplacoid has very thin cuticle comparing to the normal antennal surface including the outer parts of the socket. The dorsal surface and partly ventral surface near margins in <em>Ph. montanus</em> are perforated by channels connected to the dendrites of the sensory neurons. These dendrites are visible as thin threads in the sensillum lymph which occupies the central part of the internal space in the head; they are branching below the head surface forming the dense plexus. The lateral parts of the stalk have several small cells probably secreting the cuticle of the sensillum and the aqueous sensillum lymph. The dendrites enter to the lymph in a narrow bundle. There are up to six neuron bodies with large nuclei visible below the sensilla. They are tightly packed leaving almost no space for other structures except for a few smaller hypodermal cells. There are almost no space between the groups of neurons below the neighboring receptors: the distribution of these multicellular sensilla on the antennal surface is apparently limited by the space necessary for the neuron bodies.<p> This study has been supported by the RFFI grants ! 09-04-01042a, ! 11-04-00076 and the grant from the Federal program of support for leading scientific schools NSH-3332.2010.4. <p> </p> <p <p><a href="esit11_TalksAbstracts.html" class="style3">Abstracts</a></p> <p><a href="http://www.esito-symp.org/esito11_abs_submit.html" class="style3">Abstract Submission</a></p> <p style="font-size: 24px;">Congress Programme. <a href="Esito2011_Programme.doc" target="_blank">Esito2011_Programme.doc</a> </p><p <p style="font-size: 24px;"> <p><a href="esito11_posters_guidlines.html" class="style3">Posters presentation guidlines</a></p> <p><a href="esito11_presentation_guidlines.html" class="style3">Oral presentation guidlines</a></p> <p style="font-size: 24px;">Registration Form <span class="Stile1"><a href="E2011_docs/Esito2011_Registration_form.pdf">.PDF version</a> | <a href="E2011_docs/Esito2011_Registration_form.doc">.DOC version</a></span></p> <p><a href="http://www.repinskaya.ru/index.php/contacts " class="style3">Hotel Accomodation</a>&nbsp; <strong style="font-size:20px;">http://www.repinskaya.ru/index.php/contacts </strong><a href="esito11_hotel_reservation.html" style="font-size:20px; color:red;"> </a></p> </span></p> <p><a href="http://www.esito-symp.org/esito11_t_and_t.html" class="style3">Travel and Transfer</a></p> <p><a href="MainPage6.html" class="style3">Main Page</a> </p> <p class="style4"><span class="style3"><a href="http://www.esito-symp.org/">Back to ESITO Homepage</a></span> </p> <br /> <hr> <br /> <p> <font size="4"><i>Copyright &copy; ESITO 2010-2011</i></font> <font size="-1"></font></p> <p><font size="-1"><font size="4"> Last updated: July 05, 2011</font></font></p> </body> </html>