Control of Alcohol Responses by Actin-Regulating Genes

描述（由申请人提供）：酒精滥用障碍是一个主要的卫生保健问题，每年影响数百万人在美国。酒精中毒具有显著的遗传病因学，但很少有基因是已知的，显着有助于疾病的发展。这个计划的目标是研究调节肌动蛋白细胞骨架的基因，以及它们调节乙醇诱导的果蝇行为的分子机制。这个想法同时出现在两种模式生物中。首先，先前对果蝇突变体进行的遗传筛选发现，这些突变体对酒精的行为反应发生了改变，从而确定了调节肌动蛋白细胞骨架的多个基因的突变。第二，敲除肌动蛋白调节蛋白的小鼠对酒精的反应也发生了变化，包括自愿饮酒的增加。因此，我们假设，动态调节肌动蛋白细胞骨架是一个主要的决定因素的行为反应乙醇。我们提出了遗传，分子，生物化学和细胞培养的方法来定义两个小的GTP酶途径，Arf 6和Rho家族的GTP酶在调节酒精诱导的行为的作用。首先，我们将研究Rho-GTPases的调节蛋白RhoGAP 18 B的两种不同亚型如何差异地参与乙醇诱导的多动症和镇静的调节。其次，我们将测试Arf 6信号通路成员对酒精反应的突变。Arf 6调节质膜上的膜运输和肌动蛋白动力学。我们将使用遗传和生物化学方法来定义Rho和Arf 6信号通路之间的分子联系。第三，我们将测试其他肌动蛋白调控基因对乙醇诱导行为的贡献，特别是cofilin的作用，cofilin是一种肌动蛋白切断蛋白，控制游离球状和丝状肌动蛋白之间的平衡。这些小GT3信号通路的成员从果蝇到哺乳动物都是高度保守的，并且已知一些参与脊椎动物和无脊椎动物的复杂行为，如学习和记忆。我们预测，这些途径在乙醇诱导的行为的调节中也是功能保守的。酒精中毒是一种严重影响个人和公共健康的毁灭性疾病。这项拟议中的研究将促进我们对酗酒发展的遗传基础的理解。这反过来将导致识别新的风险因素和潜在的治疗目标，用于治疗酒精滥用障碍。 公共卫生相关性：酒精中毒是一种毁灭性的疾病，严重导致死亡，残疾和医疗费用。这项研究的目的是了解决定和调节酒精行为反应的基因。在进行这项研究时，我们希望确定酗酒发展的风险因素，并为开发新的治疗策略提供线索，以帮助治疗酒精使用障碍。

DESCRIPTION (provided by applicant): Alcohol abuse disorders are a major health care concern that affect millions of people every year in the United States. Alcoholism has a significant genetic etiology, but few genes are known that significantly contribute to the development of the disease. The goal of this proposal is to study genes regulating the actin cytoskeleton, and the molecular mechanisms by which they do so, to regulate ethanol-induced behaviors in Drosophila. This idea emerged in parallel in two model organisms. First, previous genetic screens for Drosophila mutants with altered behavioral responses to alcohol identified mutations in multiple genes regulating the actin cytoskeleton. Second, mice with a knock-out of an actin regulatory protein also showed altered responses to alcohol, including increased voluntary drinking. We therefore postulate that the dynamic regulation of the actin cytoskeleton is a major determinant of behavioral responses to ethanol. We propose genetic, molecular, biochemical, and cell culture approaches to define the roles of two small GTPase pathways, the Arf6, and Rho-family of GTPases in regulating alcohol-induced behaviors. First, we will study how two distinct isoforms of a regulatory protein of Rho-GTPases, RhoGAP18B, are differentially involved in the regulation of both ethanol-induced hyperactivity, and sedation. Second, we will test mutations in members of the Arf6 signaling pathway for their responses to alcohol. Arf6 regulates membrane traffic and actin dynamics at the plasma membrane. We will use genetic, and biochemical approaches to define what the molecular links are between the Rho and Arf6 signaling pathways. Third, we will test the contribution of other actin regulatory genes to ethanol-induced behaviors, notably the role of cofilin, an actin-severing protein that controls the balance between free globular and filamentous actin protein. The members of these small GTPase signaling pathways are highly conserved from Drosophila to mammals, and some are known to participate in complex behaviors such as learning and memory, in vertebrates and invertebrates. We predict that these pathways are also functionally conserved in their regulation of ethanol-induced behaviors. Alcoholism is a devastating disease that severely impacts personal, and public health. The proposed research will advance our understanding of the genetic basis for the development of alcoholism. This in turn, will result in the identification of new risk factors and potential therapeutic targets for the treatment of alcohol abuse disorders. PUBLIC HEALTH RELEVANCE: Alcoholism is a devastating disorder that significantly contributes to mortality, disability, and to healthcare costs. The goal of this research is to understand the genes that determine, and mediate the behavioral responses to alcohol. In conducting this research, we hope to identify risk factors for the development of alcoholism, as well as provide leads for the development of new therapeutic strategies aiding in the treatment of alcohol use disorders.