Olfactory processing and learning of complex scents in insects

对于所有动物来说，处理生物学上重要的气味的能力-通常是数十到数百种挥发性化学物质的混合物-对基本行为有着根本的影响。此外，嗅觉功能的缺陷是许多影响学习和记忆的神经退行性疾病的早期发作的指标。尽管接受气味混合物对行为的重要性，但在识别大脑中嗅觉处理的机制方面存在重要差距（例如，在昆虫的触角叶[AL]），以及大脑的下游区域如何在学习过程中进一步处理气味信息。该项目将使用跨学科的方法，将新颖的化学分析和电生理技术与行为动物（天蛾）的同步电生理记录相结合，以了解气味是如何处理的，并确定这些信息是如何在学习过程中解码的。嗅觉信号在昆虫行为调控中起着重要作用。该项目将：（1）表征由蛾授粉的不同花卉物种的气味组成，并识别驱动肾小球反应和引发行为的气味中的关键气味剂;（2）确定编码机制，通过该编码机制，来自这些不同花卉物种的气味（其特征可能不同）激活相同的肾小球回路以引发行为;以及（3）在蛾学习气味和奖励之间的关联时，在AL和蘑菇体（学习和记忆的部位）中使用同时的多通道记录，以识别混合信息如何被解码以及食欲学习如何调节气味表征。因此，该项目将促进对飞蛾等害虫行为的嗅觉控制的理解，并有助于最终控制人类疾病的昆虫媒介，如蚊子。此外，该项目还将向学生介绍跨学科研究，并向公众广泛宣传动物行为的重要性。公众将通过公民科学项目参与该项目。最后，该项目包括培训本科生、研究生和博士后助理，帮助他们为独立的科学生涯做好准备。

For all animals, the ability to process biologically important odors - often mixtures of tens to hundreds of volatile chemicals - has a fundamental consequence for essential behaviors. Additionally, deficits in olfactory function are indicators of early onset of many neurodegenerative diseases that affect learning and memory. Despite the acceptance of the importance of odor mixtures for behavior, there are important gaps in identifying the mechanisms of olfactory processing in the brain (e.g., in the antennal lobe [AL] of insects), and how downstream areas of the brain further process that odor information during learning. This project will use an interdisciplinary approach that combines novel chemical analytical and electrophysiological techniques with simultaneous electrophysiological recordings from behaving animals (Manduca sexta moths) to understand how odors are processed and identify how this information is decoded during learning. Olfactory cues play fundamental roles in mediating insect behavior. This project will: (1) characterize the scent composition of diverse flower species pollinated by moths and identify key odorants in the scents that drive glomerular responses and elicit behavior; (2) determine the coding mechanism(s) by which the scents from these diverse flower species, which can differ in their profiles, activate the same glomerular circuit(s) to elicit behavior; and (3) use simultaneous multi-channel recording in the AL and mushroom body (the site of learning and memory) while the moth learns association between an odor and a reward to identify how mixture information is decoded and how appetitive learning modulates odor representation. The project will thus advance understanding of olfactory control of behavior of pests like moths and can contribute to the eventual control of insect vectors of human disease, like mosquitoes. Furthermore, the project will also introduce students to interdisciplinary research, as well as broadly communicate the importance of animal behavior to the public. Members of the public will be involved in the project through a citizen science project. Finally, the project includes the training of undergraduates, graduate students and postdoctoral associates and helps prepare them for independent scientific careers.