A novel GPCR-mediated steroid signaling that controls alcohol-induced behavior

一种新型 GPCR 介导的类固醇信号传导，可控制酒精诱发的行为

• 批准号: 8427822
• 负责人: TOSHIHIRO KITAMOTO
• 金额: $ 7.55万
• 依托单位: UNIVERSITY OF IOWA
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-12-05 至 2014-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8427822
• 关键词: Adult; Affect; Alleles; Behavior Control; Behavioral; Behavioral Genetics; Binding; Biological; Brain; Catecholamines; Cells; Development; Disease; Dopamine; Drosophila genus; Drosophila melanogaster; Ecdysone; Epidermal Growth Factor Receptor; Exhibits; Exposure to; Foundations; Functional disorder; G-Protein-Coupled Receptors; Gene Expression; Genetic; Genomics; Goals; Grant; Health; Insecta; Insulin; Investigation; Knowledge; Ligands; Mediating; Mental disorders; Messenger RNA; Methods; Mission; Molecular; Nervous System Physiology; Nervous system structure; Neurologic; Neurons; Nuclear; Outcome; Pattern; Peptides; Phenocopy; Play; Prevention strategy; Proteins; Public Health; Receptor Signaling; Regulation; Research; Resistance; Role; Signal Transduction; Site; Steroids; Testing; Work; activating transcription factor; alcohol behavior; alcohol effect; alcohol exposure; alcohol response; alcohol use disorder; base; dopaminergic neuron; ecdysone receptor; in vivo; innovation; insight; knowledge base; mutant; nervous system disorder; non-genomic; novel; public health relevance; research study; response; sedative; steroid hormone; steroid hormone receptor; tool

DESCRIPTION (provided by applicant): Steroid hormones play a critical role in various neurological and psychiatric conditions. In addition to the "genomic" mechanisms involving nuclear steroid hormone receptors, biological effects of steroids are also mediated by "nongenomic" mechanisms that occur rapidly and independently of new mRNA synthesis. The functions and molecular mechanisms for such unconventional steroid signaling, particularly in the nervous system, are still poorly understood. This gap in the knowledge base represents an important unmet need for a mechanism-based understanding of nervous system disorders related to steroid hormones. The long-term goal is to understand how steroid hormones modulate nervous system functions and thereby control behavior. The objective of this particular application is to elucidate the fundamental mechanisms for nongenomic steroid signaling that controls ethanol-induced behaviors using the fruit fly Drosophila. Recent genetic studies in the applicant's lab demonstrate that DopEcR, a G-protein coupled receptor (GPCR) for the insect steroid hormone ecdysone, plays a significant role in behavioral responses to ethanol. This new finding provides an unprecedented opportunity to investigate the underpinnings for a novel GPCR-mediated steroid signaling that is important for alcohol-induced behavior, by taking advantage of Drosophila genetics. The central hypothesis is that DopEcR is a unique dual receptor for ecdysone and dopamine, and that it modulates resistance to the sedative effects of ethanol by negatively regulating epidermal growth factor receptor (EGFR) signaling. To test this hypothesis and attain the objective of this application, we will pursue the following two specific aims: 1) Determine the expression pattern of DopEcR and sites of its actions; and 2) Identify molecular components involved in DopEcR-mediated signaling. Under the first aim, immunological and genetic methods will be used to determine the anatomical localization of DopEcR protein in the adult brain, whereas rescue and phenocopy experiments will be performed to identify brain neurons involved in DopEcR-mediated steroid actions. Under the second aim, roles of two ligands (ecdysone and dopamine) and potential downstream signaling (EGFR signaling) in DopEcR actions will be investigated using pharmacological and genetic methods. The genetic approach is innovative, because it utilizes not only a null allele, but also various genetic tools uniquely available in Drosophila to study the mechanisms responsible for nongenomic steroid signaling. The expected outcomes will form an essential foundation for understanding the novel nongenomic steroid signaling that plays critical roles in regulation of alcohol-induced behavior. This study is significant, because it is expected to provide strong mechanism-based in vivo evidence for a novel steroid signaling in the nervous system, which may ultimately contribute toward the development of innovative strategies for the prevention and treatment of alcohol use disorders as well as other common diseases that are affected by steroid hormones.

描述（由申请人提供）：类固醇激素在各种神经系统和精神病疾病中起关键作用。除了涉及核类固醇激素受体的“基因组”机制外，类固醇的生物学作用还由迅速和独立于新的mRNA合成而迅速而独立于新的MRNA合成的“非原始组”机制介导。这种非常规类固醇信号传导的功能和分子机制，尤其是在神经系统中，仍然对此知之甚少。知识库中的这一差距代表了对基于机制的对与类固醇激素有关的神经系统疾病的理解的重要需求。长期目标是了解类固醇激素如何调节神经系统的功能，从而控制行为。该特定应用的目的是阐明使用果蝇果蝇来控制乙醇诱导的行为的非根原固醇信号的基本机制。申请人实验室中的遗传研究表明，DOPECR是一种用于昆虫类固醇激素ecdysone的G蛋白偶联受体（GPCR），在对乙醇的行为反应中起着重要作用。这一新发现提供了一个前所未有的机会，可以利用果蝇遗传学来研究新型GPCR介导的类固醇信号的基础，该基础对于酒精诱导的行为很重要。中心假设是dopeCR是ecdysone和多巴胺的独特双受体，并且通过负调节表皮生长因子受体（EGFR）信号传导来调节乙醇镇静作用的耐药性。为了检验这一假设并实现了本应用的目的，我们将追求以下两个具体目的：1）确定dopecr的表达模式及其作用的位置； 2）确定参与多帕克介导的信号传导的分子成分。在第一个目的下，将使用免疫学和遗传方法来确定成年大脑中dopeCR蛋白的解剖学定位，而将进行救援和苯屈术实验，以鉴定参与多皮克R介导的类固醇作用的脑神经元。在第二个目标下，将使用药理和遗传方法研究两个配体（ecdysone和多巴胺）和潜在的下游信号传导（EGFR信号传导）的作用。遗传方法具有创新性，因为它不仅利用了无效的等位基因，而且还利用了果蝇中独特可用的各种遗传工具来研究负责非原化类固醇信号传导的机制。预期的结果将构成理解新型非原始类固醇信号传导的基础，该信号在调节酒精诱导的行为中起着关键作用。这项研究很重要，因为预计它将为神经系统中新型的类固醇信号传导提供强大的基于机制的体内证据，这最终可能有助于开发用于预防和治疗酒精使用障碍的创新策略以及其他受类固醇激素影响的常见疾病。