Genetic Analysis of Olfaction

描述（由申请人提供）：本研究的广泛长期目标是阐明对果蝇雄性特异性挥发性信息素11-顺式醋酸乙烯酯（cVA）敏感性的分子机制。这项工作意义重大，因为了解果蝇中的信息素信号转导将转化为控制传播人类疾病和破坏作物的昆虫繁殖的新方法。在上一个资助周期中，我们在阐明cVA感知背后的机制方面取得了重大进展。我们发现了一个独特的信号传导模式，其中信息素敏感神经元的激活是由细胞外气味结合蛋白LUSH的构象激活介导的。我们已经鉴定了几种蛋白质，它们是由激活的LUSH触发的神经元受体复合物的组分，包括果蝇气味受体家族的成员Or 67 d和果蝇CD 36的同源物SNMP，CD 36是一种与人类动脉粥样硬化和血脂异常有关的膜蛋白。我们还发现了四个新的基因产物，正常的信息素检测在一个向前的遗传筛选。在下一个资金周期，我们准备通过探索这些因素如何介导cVA敏感性来取得快速进展。我们提出了一个多学科的方法，包括遗传学，电生理学，生物化学，细胞和结构生物学。第一个目的是进一步定义激活的LUSH在信息素检测级联中与T1树突相互作用。我们还将启动实验，以了解Or 67 d中的单个氨基酸突变如何消除信号传导。第二个目的是确定我们发现的LUSH构象激活机制是否对其他OBP是保守的。第三个目的是确定四个新的cVA敏感性因子，奇数，面包车，vainsB和vainsE中确定的前向遗传筛选的作用。目的4是确定cVA信号检测映射到第二条染色体所需的组件，使我们更接近我们的总体目标，即确定对cVA敏感性重要的完整基因产物集。这里概述的研究的完成将推进我们对昆虫挥发性信息素信号的理解，将确定新的目标来操纵昆虫行为，并将指导未来在更复杂的动物模型系统中对信息素信号的研究。 公共卫生相关性：昆虫携带人类疾病，每年造成数百万人死亡;仅疟疾一项每年就造成100多万人死亡。昆虫也影响农业，每年摧毁价值数十亿美元的农作物。许多昆虫行为，包括交配，都是由信息素的感知触发的。了解如何在分子水平上检测信息素将提供新的目标来操纵信息素通信，长期目标是阻断交配信号和其他信息素引导的行为在病原昆虫。我们已经确定了几个基因在果蝇挥发性信息素检测所必需的，并将阐明这些因素在信息素检测中的作用。

DESCRIPTION (provided by applicant): The broad long-term objective of this research is to elucidate the molecular mechanisms underlying sensitivity to the Drosophila male-specific volatile pheromone, 11-cis vaccenyl acetate (cVA). This work is significant because understanding pheromone signal transduction in Drosophila will translate into new methods to control reproduction in insects that transmit human diseases and destroy crops. In the last funding cycle, we made significant progress toward elucidating the mechanisms underlying cVA perception. We discovered a unique signaling paradigm in which activation of pheromone-sensitive neurons is mediated by conformational activation of the extracellular odorant binding protein, LUSH. We have identified several of the proteins that are components of the neuronal receptor complex triggered by activated LUSH, including Or67d, a member of the Drosophila odorant receptor family, and SNMP, a Drosophila homolog of CD36, a membrane protein implicated in atherosclerosis and dyslipidemia in humans. We also found four new gene products essential for normal pheromone detection in a forward genetic screen. In the next funding cycle, we are poised to make rapid progress by exploring how these factors mediate cVA sensitivity. We propose a multidisciplinary approach that includes genetics, electrophysiology, biochemistry, cell and structural biology. The first aim is to further define what activated LUSH interacts with on the T1 dendrites in the pheromone detection cascade. We will also initiate experiments to understand how a single amino-acid mutation in Or67d eliminates signaling. The second aim is to establish if the conformational activation mechanism we have uncovered for LUSH is conserved for other OBPs. The third aim is to define the roles of four new cVA sensitivity factors, odd, vans, vainsB and vainsE identified in the forward genetic screen. Aim 4 is to identify the components required for cVA signal detection mapping to the second chromosome, bringing us closer to our overall goal of identifying the complete set of gene products important for cVA sensitivity. The completion of the studies outlined here will advance our understanding of volatile pheromone signaling in insects, will identify new targets to manipulate insect behavior, and will guide future studies on pheromone signaling in more complex animal model systems. PUBLIC HEALTH RELEVANCE: Insects carry human diseases that kill millions of people every year; malaria alone accounts for over one million deaths annually. Insects also impact agriculture, destroying billions of dollars worth of crops annually. Many insect behaviors, including mating, are triggered by perception of pheromones. Understanding how pheromones are detected at the molecular level will provide new targets to manipulate pheromone communication, with the long-term goal of blocking mating signals and other pheromone-guided behaviors in pathogenic insects. We have identified several genes essential for volatile pheromone detection in Drosophila and will elucidate the roles of these factors in pheromone detection.