Functional analysis of insect taste receptors

昆虫味觉受体的功能分析

• 批准号: 8613010
• 负责人: Anupama Arun Dahanukar
• 金额: $ 34.55万
• 依托单位: UNIVERSITY OF CALIFORNIA RIVERSIDE
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-12-01 至 2018-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8613010
• 关键词: Address; Anopheles gambiae; Arthropods; Behavior; Behavioral; Behavioral Genetics; Brain; Categories; Cells; Chemicals; Cues; Culicidae; Decision Making; Dengue; Detection; Disease; Drosophila genus; Drosophila gustatory receptor; Ectopic Expression; Edible Plants; Family; Feeding behaviors; Food; Food Selections; Genetic; Glean; Goals; Human; Individual; Ingestion; Insect Control; Insecta; Ligands; Light; Malaria; Modality; Molecular; Molecular Genetics; Neurons; Odorant Receptors; Phylogeny; Plant Sources; Play; Property; Public Health; Receptor Gene; Receptor Inhibition; Research; Role; Site; Source; System; Taste Perception; Testing; Translating; Variant; West Nile Fever; base; design; egg; feeding; fly; genetic analysis; improved; in vivo; inhibitor/antagonist; innovation; loss of function; mutant; novel; novel strategies; promoter; public health relevance; receptor; receptor function; research study; response; sugar; sweet taste perception; tool; transmission process

DESCRIPTION (provided by applicant): The ability to detect various chemicals and to use this information to make feeding decisions is a defining feature of the taste system from humans to insects. In Drosophila, a large family of Gustatory receptor (Gr) genes encodes divergent receptors that are expressed in taste neurons. Despite ongoing efforts, we know little about the ligand response profiles of individual Gr proteins in any insect. Gr proteins represent a novel family, distantly related only to insect Odorant receptor (Or) proteins, and thus lack the advantage of structural or functional comparisons with equivalent groups. The same feature of exclusivity in insects and arthropods, however, makes Grs attractive targets for developing novel strategies of insect control. In preliminary studies, we have developed an in vivo functional expression system in which to identify the response properties of individual insect Grs. The overarching objective of this proposal is to elucidate functional properties of individual taste receptors in Drosophila and the malaria mosquito Anopheles gambiae, and their role in instructing feeding behavior. We propose to systematically characterize the tuning profiles of selected taste receptors of the fruit fly and the mosquito by taking advantage of our ectopic expression system. The experiments are designed to reveal fundamental features of Gr function including the activation and inhibition profiles of individual receptors, the extent of functional overlap between receptors, and the relationship between receptor sequence and function. The approach to address these questions will be to: 1) Identify the tuning profiles of internally expressed Drosophila taste receptors, and evaluate their roles in feeding behavior by genetic analysis, 2) Characterize novel cross-modality interactions between Drosophila sweet taste receptors and bitter tastants, and examine the functional role of sweet taste neuron inhibition in feeding behavior, and 3) Identify activators and inhibitors of putative sweet taste receptors of An. gambiae and characterize the response profiles of endogenous sweet taste neurons in the mosquito proboscis. The proposed research is innovative because it employs a novel in vivo ectopic expression system for decoding Gr function and combines it with molecular genetics, electrophysiological, and behavioral analyses of gustatory function. The research is significant because functional analysis of Gr genes will contribute to our understanding of the fundamental principles by which tastants are encoded across a diverse repertoire of receptors and how mechanisms of tastant detection translate to food selection. Additionally, our studies will shed light on molecular and cellular mechanisms of sugar detection in mosquitoes, which may be applicable for improving sugar-baited traps that are used in mosquito surveillance and control strategies. !

描述（由申请人提供）：检测各种化学物质并使用该信息做出进食决定的能力是从人类到昆虫的味觉系统的定义特征。在果蝇中，一个大家族的味觉受体（Gr）基因编码在味觉神经元中表达的不同受体。尽管正在进行的努力，我们知道很少的配体响应曲线的个别Gr蛋白在任何昆虫。Gr蛋白代表一个新的家族，仅与昆虫气味剂受体（Or）蛋白有较远的关系，因此缺乏与等效组进行结构或功能比较的优势。然而，在昆虫和节肢动物中的排他性的相同特征使得Grs成为开发昆虫控制新策略的有吸引力的目标。在初步研究中，我们已经开发了一种体内功能性 表达系统，以确定个别昆虫Grs的响应特性。该提案的总体目标是阐明果蝇和疟疾蚊子冈比亚按蚊中个体味觉受体的功能特性，以及它们在指导摄食行为中的作用。我们建议利用我们的异位表达系统，系统地表征果蝇和蚊子的选定味觉受体的调谐概况。实验旨在揭示Gr功能的基本特征，包括单个受体的激活和抑制概况，受体之间的功能重叠的程度，以及受体序列和功能之间的关系。解决这些问题的办法是：1）确定内部表达的果蝇味觉受体的调谐谱，并通过遗传分析评估它们在摄食行为中的作用，2）表征果蝇甜味受体和苦味剂之间的新的跨通道相互作用，并检查甜味神经元抑制在摄食行为中的功能作用，和3）鉴定推定的An甜味受体的激活剂和抑制剂。gambiae的，并表征蚊子喙中内源性甜味神经元的反应谱。拟议的研究是创新的，因为它采用了一种新的体内异位表达系统解码Gr功能，并将其与味觉功能的分子遗传学，电生理学和行为分析相结合。这项研究意义重大，因为Gr基因的功能分析将有助于我们理解促味剂在不同受体库中编码的基本原理，以及促味剂检测机制如何转化为食物选择。此外，我们的研究将揭示蚊子中糖检测的分子和细胞机制，这可能适用于改进用于蚊子监测和控制策略的糖诱饵陷阱。!