Multisensory Integration for Food Perception and Behavior in Drosophila

描述（由申请人提供）：动物和人类的感官世界都非常复杂。我们目前对多感官输入如何在大脑中处理感知和行为的理解在任何动物身上都是最基本的。遗传上易处理的果蝇幼虫提供了一个独特的机会，行为和神经生物学研究的整合多种感官形式的感知和行为。蝇幼虫显示出丰富的复杂行为，并具有高度进化但数字简单的中枢神经系统（CNS）。果蝇幼虫的大脑与人脑有许多相似之处，包括两个半球，具有高局部神经元聚集（也称为局部处理单元或LPU）和长程投射，六种主要神经递质，多种神经肽。越来越多的强大的分子遗传学和神经生物学工具将进一步允许我们对感兴趣的神经过程或行为的神经基质和过程进行深入的后续研究。我们最近的研究表明，像哺乳动物一样，有吸引力的食物气味会引起果蝇幼虫在奖励驱动下过量进食容易获得的富含糖的食物。多巴胺（DA）系统的缺陷阻断了食欲气味引起食欲行为的能力。我们还确定了少量的第三级嗅觉神经元合成DA。这些DA神经元的激活模仿食欲气味刺激的行为效应。另一方面，OA系统介导幼虫对容易获得的糖介质的摄食反应。该应用程序将集中在探索多感官整合的食物感知和行为的蝇幼虫模型测试的几个关键方面的一种新的工作模型。该提案有两个具体目标：1）行为和神经生物学研究多种嗅觉和味觉模式在调节对可口食物的食欲中的整合; 2）分析大脑状态对嗅觉和味觉模式在调节对可口食物的食欲中的整合的影响。我们期望这些研究的成功结果将为整合不同的嗅觉和味觉模式调节对可口食物的食欲提供新的见解。此外，从这些研究中获得的知识将有助于对感知和行为以及相关神经系统疾病的多感觉方式整合的一般理解。

DESCRIPTION (provided by applicant): The sensory world of animals and humans alike is enormously complex. Our current understanding of how multisensory inputs are processed in the brain for perception and behavior remains rudimentary at best in any animals. The genetically tractable Drosophila larva offers a unique opportunity for behavioral and neurobiological studies of the integration of multiple sensory modalities for perception and behavior. Fly larvae display a rich repertoire of complex behaviors, and have a highly evolved yet numerically simple central nervous system (CNS). The brain of fly larvae shares many similarities with the human brain including two hemispheres with high local clustering of neurons (also named the local processing unit or LPU) and long-range projections, six major neurotransmitters, a variety of neuropeptides. An increasingly large set of powerful molecular genetic and neurobiological tools available will further allow us to perform in- depth follow-up studies of the neural substrates and processes underlying a neural process or behavior of interest. We have recently shown that like in mammals, attractive food odors elicited reward-driven overeating of readily accessible sugar-rich food in Drosophila larvae. Deficiencies in the dopamine (DA) system blocked the capacity of the appetitive odor to elicit the appetitive behavior. We have also identified a small number of third-order olfactory neurons that synthesize DA. Activation of these DA neurons mimicked the behavioral effect of appetitive odor stimulation. On the other hand, the OA system mediates larval feeding response to readily available sugar media. This application will be focused on exploring multisensory integration for food perception and behavior in the fly larva model by testing several key aspects of a novel working model. The proposal has two specific aims: 1) behavioral and neurobiological studies of integration of multiple olfactory and gustatory modalities in modulating appetite for palatable food; 2) analyses of the effects of brain states on integration of olfactory and gustatory modalities in modulating appetite for palatable food. We expect that the successful outcomes of these studies will provide novel insights into integration of different olfactory and gustatory modalities in modulating appetite for palatable food. Furthermore, the knowledge gained from these studies will contribute to the general understanding of the integration of multisensory modalities for perception and behavior as well as related neurological disorders.