Initial Stages of Olfactory Information Processing

嗅觉信息处理的初始阶段

• 批准号: 9288136
• 负责人: Chih-Ying Su
• 金额: $ 31.95万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN DIEGO
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-06-06 至 2021-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9288136
• 关键词: Address; Anatomy; Animals; Behavior; Behavioral; Behavioral Assay; Biophysics; Brain region; Caliber; Cells; Cerebellum; Communication; Complex; Courtship; Cues; Data; Disease; Disease Vectors; Drosophila genus; Drosophila melanogaster; Electron Microscopy; Electrophysiology (science); Engineering; Face; Food; Genetic; Goals; Health; Hippocampus (Brain); Human; Imaging technology; Individual; Insect Control; Insect Vectors; Insecta; Investigation; Lead; Logic; Malaria; Mammals; Mediating; Modeling; Molecular Genetics; Morphology; Neurons; Odors; Olfactory Nerve; Olfactory Pathways; Olfactory Receptor Neurons; Pheromone; Physiological; Population; Prevalence; Process; Property; Research; Research Design; Resistance; Retina; Role; Sensory Hair; Shapes; Smell Perception; Stimulus; Surveys; Synapses; System; Testing; Tissues; Transgenic Organisms; Work; behavior influence; behavioral response; design; disorder control; extracellular; fly; genetic analysis; image reconstruction; information processing; insight; neural circuit; neuronal cell body; novel; optogenetics; relating to nervous system; sensory system; vector control

PROJECT SUMMARY/ABSTRACT The long-term goal of this project is to reveal the mechanisms by which complex odors are encoded, with a special focus on the initial stages of olfactory information processing. The research design takes advantage of the anatomical simplicity and powerful genetic toolkit of Drosophila melanogaster, which allows systematic molecular genetic analysis of olfactory circuits as well as in-depth physiological and behavioral analysis of olfactory function. The results may have major implications for the control of insect vectors of disease. The project focuses on ephaptic interactions, a novel, non-synaptic form of olfactory circuit communication, which take place between any two grouped olfactory receptor neurons (ORNs) housed in the same insect sensory hair (sensillum). Despite its ubiquity, how ephaptic communication regulates olfactory function and behavior is poorly understood. We recently provided the first description of the importance of ephaptic inhibition in insect olfaction. In the current study, we will first focus on defining the importance of ephaptic excitation. A systematic, functional survey will be performed to define the strength of ephaptic excitation between grouped ORNs (Aim 1). The respective electrotonic properties of grouped ORNs will also be determined (Aim 2). The strength of ephaptic interactions will be quantified between a pair of ORNs from both directions with a view to testing the hypothesis that ephaptic interactions are asymmetric across sensillum types. Furthermore, the ultrastructure of grouped ORNs will be described using serial block-face electron microscopy (SBEM) and 3D reconstruction imaging technologies (Aim 3). This Aim is designed to identify the biophysical factors that underlie asymmetric ephaptic interactions in a sensillum. Morphological features of an identified ORN, such as dendritic caliber, number of dendritic branches, as well as soma size, will be analyzed and compared between neighboring ORNs. The hypothesis that the physically larger ORN in a pair exerts stronger ephaptic interactions upon its neighbor will be tested. This Aim could also lead to critical technical breakthroughs to broaden the application of SBEM in illuminating the 3D ultrastructure of any identified cell in diverse tissues. Lastly, the functional importance of ephaptic interactions in odor-guided behavior will be determined (Aim 4). Specifically, we will extend our behavioral assay and define the role of ephaptic inhibition on courtship behavior in sensillum which houses ORNs responsive to pheromone cues. We will also perform the first test of the functional importance of ephaptic excitation between another ORN pair that mediates behavioral responses to food odors. The proposed research will determine the functional importance and biophysical principles of a novel form of olfactory circuit interaction mechanism. These findings have the potential to revolutionize our understanding of olfactory information processing in insects, and may reveal general principles that govern chemosensory behavior throughout the animal kingdom.

项目概要/摘要 该项目的长期目标是揭示复杂气味的编码机制， 特别关注嗅觉信息处理的初始阶段。研究设计利用了 黑腹果蝇的解剖学简单性和强大的遗传工具包，使得系统性研究成为可能 嗅觉回路的分子遗传学分析以及深入的生理和行为分析 嗅觉功能。研究结果可能对疾病昆虫媒介的控制具有重大意义。 该项目重点关注嗅觉相互作用，这是一种新颖的非突触形式的嗅觉回路交流， 发生在同一昆虫体内任意两个分组的嗅觉受体神经元 (ORN) 之间 感觉毛（感受器）。尽管它无处不在，但触觉交流如何调节嗅觉功能和 人们对行为知之甚少。我们最近首次描述了触觉的重要性 抑制昆虫嗅觉。在当前的研究中，我们将首先关注定义 ehaptic 的重要性 励磁。将进行系统的功能调查来定义触觉兴奋的强度 分组的 ORN 之间（目标 1）。分组的 ORN 各自的电紧张特性也将是 确定（目标 2）。触觉相互作用的强度将在一对 ORN 之间进行量化 方向，以检验触觉相互作用在感觉器之间不对称的假设 类型。此外，分组 ORN 的超微结构将使用串行块面电子来描述 显微镜 (SBEM) 和 3D 重建成像技术（目标 3）。该目标旨在确定 感觉器中不对称触觉相互作用的生物物理因素。形态特征 将分析已识别的 ORN，例如树突直径、树突分支数量以及胞体大小 并在相邻的 ORN 之间进行比较。假设一对中物理尺寸较大的 ORN 发挥作用 将测试对其邻居的更强的触觉相互作用。这一目标还可能导致关键的技术 突破性突破，扩大了 SBEM 在阐明任何已识别细胞的 3D 超微结构方面的应用 不同的组织。最后，触觉相互作用在气味引导行为中的功能重要性将是 确定（目标 4）。具体来说，我们将扩展我们的行为分析并定义触觉抑制的作用 感器中的求偶行为，感器中含有对信息素线索做出反应的 ORN。我们还将表演 第一次测试另一对 ORN 介导的触觉兴奋的功能重要性 对食物气味的行为反应。 拟议的研究将确定一种新型形式的功能重要性和生物物理原理 嗅觉回路相互作用机制。这些发现有可能彻底改变我们对 昆虫的嗅觉信息处理，并可能揭示控制化学感应的一般原理 整个动物界的行为。