Neuropeptide Modulation of Courtship Behaviors

描述（由申请人提供）：本研究项目研究神经肽如何调节挥发性信息素的嗅觉处理并塑造下游求爱行为。我们作为一个多pi团队正在使用模型遗传系统果蝇来解决这个问题。CG4395基因编码一个与哺乳动物降钙素受体及降钙素基因相关肽高度相关的B类肽G蛋白偶联受体（GPCR）。CG4395特异性抗体和CG4395启动子的构建表明，CG4395在响应信息素的嗅觉受体神经元以及与求偶行为和可塑性有关的大脑高级区域中显著表达。值得注意的是，缺乏CG4395基因表达的突变雄蝇表现出异常的求偶行为。此外，这种行为缺陷可以通过在嗅感觉神经元中表达CG4395基因而恢复到突变动物。这些发现使我们假设通过CG4395进行的肽神经调节调节了求爱相关信息素的加工。CG4395 GPCR是一个孤儿，但它对果蝇头部提取物中的肽因子有有效的反应，我们已经通过三个HPLC步骤极大地富集了这些肽因子，现在提议将其纯化到均匀性。我们还建议利用果蝇遗传学提供的力量来研究CG4395受体和肽配体，分别和一起，在体内了解受体信号传导的位置和时间。我们将结合一系列分子遗传学工具和详细的行为分析来了解受体和配体在求偶中的作用。此外，我们将采用一种新的基因编码的cAMP水平实时报告器，该报告器使用一种新的基因报告器显示的由CG4395调节的体内FRET测量。要实现这些目标，需要的技能比目前任何一个果蝇实验室都要高。因此，这个研究项目代表了三个独立小组的合作努力，每个小组都贡献了特定的专业知识和技术经验。神经调节递质系统调节许多高级大脑功能，包括注意力、记忆、情绪、食欲、社会行为和攻击。当传递系统出错时，通常会出现临床问题。因此，识别调节肽和同源受体是研究行为机制的关键。GPCRs及其信号通路在进化过程中高度保守，因此我们旨在描述的神经调节的分子机制将为治疗干预提供潜在的途径。

DESCRIPTION (provided by applicant): This research program addresses how a neuropeptide modulates olfactory processing of volatile pheromone information and shapes downstream courtship behavior. We are approaching this issue as a Multi-PI team using the model genetic system, Drosophila. The CG4395 gene encodes a Class B peptide G protein-coupled receptor (GPCR) highly related to mammalian receptors for Calcitonin and Calcitonin Gene Related Peptide. CG4395 specific antibodies and CG4395-promoter constructs reveal that CG4395 is prominently expressed in olfactory receptor neurons that respond to pheromone as well as in higher regions of the brain that have been implicated in courtship behavior and plasticity. Significantly, mutant male flies that lack CG4395 gene expression exhibit aberrant courtship behavior. Furthermore, this behavioral defect can be restored to mutant animals by expressing a CG4395 transgene in olfactory sensory neurons. These findings lead us to hypothesize that peptide neuromodulation via CG4395 regulates courtship-relevant pheromone processing. The CG4395 GPCR is an orphan, but it responds potently to a peptide factor in Drosophila head extracts which we have greatly enriched by three HPLC steps and now propose to purify to homogeneity. We also propose to use the power afforded by Drosophila genetics to study the CG4395 receptor and peptide ligand, separately and together, in vivo to learn where and when receptor signaling occurs. We will combine a battery of molecular genetic tools with detailed behavioral analyses to understand the roles of the receptor and ligand in courtship. In addition we will employ a novel genetically-encoded real-time reporter of cAMP levels that uses in vivo FRET measurement regulated by CG4395 as revealed by a novel genetic reporter. To achieve these goals demands skills greater than can be assembled in any current Drosophila laboratory. Therefore, this research program represents the collaborative efforts of three independent groups, each of which contributes specific expertise and technical experience. Neuromodulatory transmitter systems regulate numerous higher brain functions including attention, memory, mood, appetite, social behavior and aggression. When transmitter systems go awry, clinical problems often arise. Identifying modulatory peptides and cognate receptors is therefore a key endeavor in studying the mechanisms underlying behavior. GPCRs and their signaling pathways are highly conserved in evolution, thus the molecular mechanisms of neuromodulation we aim to describe will offer potential avenues for therapeutic intervention. PUBLIC HEALTH RELEVANCE Neuromodulation is fundamentally important for higher brain functions and regulates diverse brain-based phenomena including attention, memory, mood, appetite and aggressive behaviors. The normal actions of monoamine and peptide transmitters systems are keys to such modulation and when these transmitter systems go awry, these processes are compromised and clinical problems arise. This research program uses biochemical and genetic approaches to explore fundamental mechanisms underlying modulation of the neural circuits that regulate reproductive behaviors (courtship) in the model system Drosophila.