RUI: Neurobehavioral Analysis of the Regulation of Courtship Initiation in Drosophila Melanogaster

RUI：果蝇求爱启动调节的神经行为分析

• 批准号: 1554572
• 负责人: Rachael French
• 金额: $ 42.88万
• 依托单位: San Jose State University Foundation
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-04-15 至 2020-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1554572&HistoricalAwards=false
• 关键词: RUI; Neurobehavioral; Analysis; Regulation; Courtship

One of the goals of neuroscience is to understand how genes direct the development of the nervous system, and how sensory input from the environment interacts with the nervous system to result in behavior. Male fruit flies of the genus Drosophila carry out a complex and stereotyped courtship ritual that provides an excellent model in which to study these processes. The correct performance of this ritual is critical for success in mating and reproduction. Mutations affecting the courtship ritual typically result in slow courtship, or failure to court entirely. However, we have identified a gene (Tre1) that, when mutated, causes unusually rapid performance of the ritual. This result is unique, and suggests a previously unknown function in mating behavior: delay of courtship. This research project aims to answer two questions: first, why would a gene exist whose function appears to be to reduce the speed of mating, which would seem to put males at a disadvantage relative to males that mate more quickly? Second, in what cells does the Tre1 gene function, and what are these cells doing during courtship behavior? In addition, to increase the exposure of women and underrepresented minority students to basic scientific research, an integral component of this project is to establish a summer mentorship program that brings high school biology teachers from local minority-serving high schools, together with their students, to the lab to design and implement behavioral genetics experiments for their classrooms.Drosophila males engage in a stereotyped courtship ritual in order to gain the favor of females. Previous research has shown that the typical result of failure to perform any of the steps correctly and in the correct order results in greatly reduced opportunities to mate. In addition, the behavioral sex determination gene fruitless (fru) has been shown to be necessary and sufficient to direct all steps of courtship behavior. Loss of the male-specific fru transcripts (fruM) typically leads to increased latency to court, inappropriate mate choice, or failure to court at all. We identified a GAL4-transgene that is inserted into the coding sequence of the Tre1 GPCR gene (Tre1-GAL4). When this GAL4 line is used to drive expression of either an RNAi targeting fruM or the feminizing transgene UAS-traF, it results in male flies that initiate courtship and achieve copulation much more quickly than control animals. This phenotype is recapitulated in males mutant for Tre1, which indicates that the Tre1 GPCR is required for normal courtship behavior. The expression pattern of Tre1-GAL4 is limited, with expression in regions consistent with olfactory reception and processing in both the peripheral and central nervous system. The activities described in this proposal identify positively the Tre1-GAL4 cells, investigate the function of those cells in courtship initiation, test the hypothesis that the Tre1-GAL4 cells are involved in mate choice, and further investigate the role of Tre1 itself in courtship initiation.

神经科学的目标之一是了解基因如何指导神经系统的发育，以及来自环境的感觉输入如何与神经系统相互作用以导致行为。果蝇属的雄性果蝇进行复杂而刻板的求偶仪式，为研究这些过程提供了一个很好的模型。这种仪式的正确表现对交配和繁殖的成功至关重要。影响求爱仪式的突变通常会导致缓慢的求爱，或者完全失败。然而，我们已经确定了一种基因（Tre1），当它发生突变时，会导致仪式异常快速的表现。这个结果是独一无二的，并且暗示了一个以前不为人知的在交配行为中的作用：求偶延迟。这个研究项目旨在回答两个问题：第一，为什么会存在一个功能似乎是降低交配速度的基因，这似乎使雄性相对于交配速度更快的雄性处于不利地位？第二，Tre1基因在什么细胞中起作用，这些细胞在求偶行为中做什么？此外，为了增加女性和少数族裔学生对基础科学研究的接触，该项目的一个组成部分是建立一个夏季指导计划，将当地少数族裔高中的高中生物教师与他们的学生一起带到实验室，为他们的课堂设计和实施行为遗传学实验。为了获得雌性的青睐，雄性果蝇会进行一种老套的求爱仪式。先前的研究表明，如果没有按照正确的顺序正确地执行任何步骤，通常会导致交配机会大大减少。此外，行为性别决定基因无果性（fru）已被证明是必要和充分的，以指导求爱行为的所有步骤。雄性特异性fru转录本（fruM）的缺失通常会导致求偶延迟增加，择偶不当或根本无法求偶。我们鉴定了一个插入Tre1 GPCR基因编码序列的gal4转基因（Tre1- gal4）。当这个GAL4系被用来驱动RNAi的表达，无论是来自或雌性化转基因UAS-traF，它导致雄蝇开始求爱和实现交配比对照动物快得多。这种表型在雄性Tre1突变体中重现，这表明Tre1 GPCR是正常求偶行为所必需的。Tre1-GAL4的表达模式是有限的，在外周和中枢神经系统中与嗅觉接收和加工一致的区域表达。本研究对Tre1- gal4细胞进行了阳性鉴定，探讨了Tre1- gal4细胞在求爱起始中的功能，验证了Tre1- gal4细胞参与配偶选择的假设，并进一步探讨了Tre1细胞本身在求爱起始中的作用。