2009 Abstracts - Association for Chemoreception Sciences

#P93 Poster session II: Chemosensory response to,and control of, feeding/NeuroethologySea hares chemically defend themselves from predatory bluecrabs and bluehead wrasse using light-harvesting moleculesin their algal dietMichiya Kamio, Linh Nguyen, Tiphani V. Grimes, MatthewNusnbaum, Melissa H. Hutchins, Seyma Yaldiz, Robyn van Dam,Charles D. DerbyNeuroscience Institute and Department of Biology,Georgia State University Atlanta, GA, USASea hares, Aplysia californica, release a purple ink secretion whenattacked by predators. This secretion is composed of twosecretions, ink and opaline, and either alone or both together candefend them by affecting chemosensory system of predators. Themolecular identities of the deterrent compounds in the ink remainlargely unknown. We asked two questions: Is A. californica ink achemical deterrent against two predators: blue crabs, Callinectessapidus, and bluehead wrasse, Thalassoma bifasciatum? and if yes,What are the active molecules? Both species were tested in twobehavioral assays: a feeding assay in which animals were offeredfood soaked (or not) in ink; and a cloud assay in which ink wassquirted at the animals. Both assays revealed that fish and crabsare deterred by ink. The identity of the active components in inkwas examined in bioassay guided fractionation using the feedingassay. Aplysioviolin (AV) was identified as the major activecomponent and phycoerythrobilin (PE) was a minor one. AV andPE have similar activities at equimolar concentrations, but becauseaplysioviolin is approximately ten times more abundant in ink,it is the major active component in ink. The structures of thesemolecules were identified using NMR, MS, and UV spectra.PE is a chromophore covalently linked to a protein to form thephotosynthetic pigment of red algae in the diet of Aplysia. AV isthe monomethyl ester of PE. AV and PE are also present in ink ofAplysia dactylomela, a sympatric sea hare with blue crabs andbluehead wrasse, at approximately the same ratio. Thus, sea haresacquire light-harvesting proteins from red algae, cleavephycoerythrobilin from the protein, convert it into aplysioviolin,and store these molecules in the ink gland, and release it aschemical deterrents against predators.from OA levels. Finally, male moth upwind flight ability wasstudied following OA injection, to identify differences insuccessful flight to artificial pheromone lures. Pending results ofthe current study, subsequent efforts will integrate learningparadigms such as the proboscis-extension reflex (PER) todecipher any influence of OA on odour learning.#P95 Poster session II: Chemosensory response to,and control of, feeding/NeuroethologyFlavor Identification and Memory in ChildrenMelinda S Brearton, Brittany Carlisle, Katheryn Pointer,Erica Mannea, Konstantin Rybalsky, Robert A FrankUniversity of cincinnati Cincinnati, OH, USAWe have previously shown that identification and memory forjelly bean flavors is improved when flavor labels are providedduring testing. The current study assessed whether similar effectswould be found in children. Children between four and elevenyears old were asked to identify and remember jelly bean flavorsin a joint flavor identification/recognition memory task. In Phase1 the children were given ten jelly beans and asked to identify theflavor of each. They were provided with four alternative flavorlabels and accompanying pictures that matched the labels. Phase 2commenced after a ten minute retention interval. Participantswere presented randomly with the ten jelly beans from Phase 1and ten new jelly beans, and asked to accurately identify eachflavor and indicate whether the jelly bean flavor had beenpresented previously in Phase 1 (old) or was being presented forthe first time (new). We found, as with adults, that identificationand memory performance improved when labels were provided,but the effect was larger for adults. We had previously found thatconsistently labeled old flavors were remembered almost perfectlyby adults. Interestingly, this same relationship was observed forchildren. This suggests that flavor knowledge and experience(rather than differences in cognitive processes) account for theobserved differences between the performance of the childrenand adults.#P94 Poster session II: Chemosensory response to,and control of, feeding/NeuroethologyRole of Octopamine in Moth OlfactionKirk HillierAcadia University Wolfville, NS, CanadaOctopamine (OA) is a significant neuromodulator within theinvertebrate nervous system. In many respects, the functional roleof OA is similar to that of other aminergic compounds such asnoradrenaline within vertebrates. This includes a direct influenceon energetic activities, arousal, learning and memory. The currentstudy investigates the effects of OA on the physiology andodour-mediated behaviours of the tobacco budworm moth,Heliothis virescens. First, a neuroanatomical study was conductedto determine the distribution of OA within this species brain,relative to other moth species. Second, OA injections were madeinto the brain and single-sensillum recordings were subsequentlymade from the antennae. In particular, the responses of male andfemale moths to female sex pheromones were compared toidentify any intersexual differences in threshold or spiking evident#P96 Poster session II: Chemosensory response to,and control of, feeding/NeuroethologyMillisecond Photoactivation of Bombykol Receptor NeuronsExpressing Channelrhodopsin-2 Triggers PheromoneSearching Behavior in Male SilkmothsMasashi Tabuchi 1,2 , Takeshi Sakurai 1 , Hidefumi Mitsuno 1 ,Ryo Minegishi 1 , Shuichi S. Haupt 1 , Takahiro Shiotsuki 3 , KeiroUchino 3 , Hideki Sezutsu 3 , Toshiki Tamura 3 , Kei Nakatani 2 ,Ryohei Kanzaki 11Research Center for Advanced Science and Technology, TheUniversity of Tokyo Tokyo, Japan, 2 Graduate School of Life andEnvironmental Sciences, University of Tsukuba Tsukuba, Japan,3National Institute of Agrobiological Sciences Tsukuba, JapanOdor-evoked spikes in olfactory receptor neurons (ORNs)induce behavioral responses within a short-timed latency.Therefore, controlling neural activity of targeted ORNs withhigh temporal resolution is important to clarify neural codesunderlying computational circuit and odor-driven behavior.The silkmoth, Bombyx mori, is a useful model for studying theolfactory system because of the straightforward input-output56 | AChemS Abstracts 2009