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

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。这一仪式的正确执行对于交配和繁殖的成功至关重要。影响求偶仪式的突变通常会导致求偶缓慢，或者完全无法求偶。 然而，我们已经确定了一个基因（Tre 1），当突变时，会导致仪式异常快速的表现。这一结果是独一无二的，并表明了一个以前未知的功能在交配行为：延迟求爱。这个研究项目旨在回答两个问题：第一，为什么会存在一个基因，其功能似乎是降低交配速度，这似乎使男性处于不利地位，相对于男性交配更快？第二，Tre 1基因在哪些细胞中起作用，这些细胞在求偶行为中起什么作用？此外，为了增加妇女和代表性不足的少数民族学生接触基础科研的机会，该项目的一个组成部分是建立一个暑期导师方案，使当地少数民族高中的高中生物教师与他们的学生一起，到实验室为他们的教室设计和实施行为遗传学实验。果蝇雄性进行一种刻板的求偶仪式，以获得女性的青睐。以前的研究表明，如果不能正确地执行任何一个步骤，并按照正确的顺序执行，那么交配的机会就会大大减少。此外，行为性别决定基因fruitless（fru）已被证明是必要的，足以指导求爱行为的所有步骤。男性特定的fru转录本（fruM）的丢失通常会导致增加的等待时间，以法院，不适当的配偶选择，或未能法院在所有。我们鉴定了GAL 4-转基因，其插入到Tre 1 GPCR基因的编码序列中（Tre 1-GAL 4）。当该GAL 4系用于驱动靶向fruM的RNAi或雌性化转基因UAS-traF的表达时，其导致雄性果蝇比对照动物更快地启动求偶并实现交配。这种表型在Tre 1的雄性突变体中重现，这表明Tre 1 GPCR是正常求偶行为所需的。Tre 1-GAL 4的表达模式是有限的，在与外周和中枢神经系统中的嗅觉接收和处理一致的区域中表达。本提案中描述的活动积极识别Tre 1-GAL 4细胞，研究这些细胞在求偶起始中的功能，测试Tre 1-GAL 4细胞参与配偶选择的假设，并进一步研究Tre 1本身在求偶起始中的作用。

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.