Taste Receptor Genes and Sensory Coding

味觉受体基因和感官编码

• 批准号: 6989039
• 负责人: Hubert O Amrein
• 金额: $ 30.79万
• 依托单位: DUKE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-01-01 至 2008-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6989039
• 关键词: Drosophilidae; RNA interference; behavior test; behavioral /social science research tag; biological signal transduction; cell surface receptors; chemoreceptors; cues; electrophysiology; ethology; gene expression; genetic mapping; olfactions; polymerase chain reaction; sensory mechanism; taste

DESCRIPTION (provided by applicant): Our long-term objective is to understand how animals recognize chemical cues present in the environment or released by mates, competitors and predators and how these cues mediate innate behaviors. Chemosensory perception provides all organisms, from bacteria to humans, with essential information about the chemical composition of the external world. In most animals, this 'chemical world' is perceived by two distinct sensory modalities: the sense of taste (gustation) and the sense of smell (olfaction). Insects show a wide range of feeding preferences that can be extremely narrow and be restricted on a single host plant, or fairly broad and include many plants and even animal cadavers. Some insects, including Drosophila, have remarkably similar taste preferences as mammals. Our general strategy is to utilize the genetically amenable system of Drosophila melanogaster to study the perception of taste. Drosophila gustatory neurons express divergent members of G-protein coupled receptors (GPCRs) that interact with non-volatile, soluble ligands. Activation of these cells is propagated to specific taste centers in the brain, where the received information is translated into a behavioral output (feeding/sucking, avoidance, courtship). Behavioral investigations and electrophysiological studies have indicated that Drosophila has a well-developed taste sensory system that can recognizes a large number of different substrates (ligands) using a large family of about 70 gustatory receptor (Gr) genes encoding divergent GPCRs. Expression studies of a small number of Gr genes revealed that a given gene is expressed in a distinct small set (1- 4 %) of gustatory neurons, creating a peripheral map in the insect gustatory system. Thus, cellular segregation of individual taste receptor genes provides a concept for high discriminatory power of different substrates that are preferentially recognized by cognate receptors. Hence, these observations have, led to the hypothesis that Drosophila and other insects recognize and distinguish significantly more taste qualities than mammals. To test this hypothesis, we propose a systematic analysis of the Drosophila taste receptor gene family by determining the global Gr expression profile and their ligand specificity. Moreover, we propose to test whether the expression map in the peripheral sensory system is translated into a functional map in the subesophageal ganglion. This research proposal has been modified based on the reviewer's recommendations, recently published reports and new data generated in our laboratory.

描述（由申请人提供）：我们的长期目标是了解动物如何识别环境中存在的化学信号或配偶、竞争对手和捕食者释放的化学信号，以及这些信号如何调节先天行为。 化学感应感知为从细菌到人类的所有生物体提供有关外部世界化学成分的基本信息。在大多数动物中，这个“化学世界”是通过两种不同的感官方式来感知的：味觉（味觉）和嗅觉（嗅觉）。昆虫表现出广泛的取食偏好，这些偏好可能非常狭窄，仅限于单一宿主植物，也可能相当广泛，包括许多植物甚至动物尸体。包括果蝇在内的一些昆虫与哺乳动物具有非常相似的味觉偏好。 我们的总体策略是利用果蝇的遗传适应性系统来研究味觉。果蝇味觉神经元表达不同的 G 蛋白偶联受体 (GPCR) 成员，这些受体与非挥发性可溶性配体相互作用。这些细胞的激活被传播到大脑中的特定味觉中心，在那里接收到的信息被转化为行为输出（进食/吸吮、回避、求爱）。行为研究和电生理学研究表明，果蝇具有发达的味觉感觉系统，可以使用编码不同 GPCR 的大约 70 个味觉受体 (Gr) 基因的大家族来识别大量不同的底物（配体）。对少量 Gr 基因的表达研究表明，给定的基因在一组不同的味觉神经元 (1-4%) 中表达，从而在昆虫味觉系统中创建了一个外围图谱。因此，个体味觉受体基因的细胞分离提供了对同源受体优先识别的不同底物的高辨别力的概念。因此，这些观察结果得出这样的假设：果蝇和其他昆虫比哺乳动物能够识别和区分更多的味觉品质。为了检验这一假设，我们提出通过确定全局 Gr 表达谱及其配体特异性来对果蝇味觉受体基因家族进行系统分析。此外，我们建议测试外周感觉系统中的表达图是否被转化为食管下神经节中的功能图。本研究提案已根据审稿人的建议、最近发表的报告和我们实验室生成的新数据进行了修改。