The Role of Circadian Genes in Drug Addiction

昼夜节律基因在毒瘾中的作用

• 批准号: 6906974
• 负责人: Colleen A McClung
• 金额: $ 14.14万
• 依托单位: UT SOUTHWESTERN MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-04-15 至 2010-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6906974
• 关键词: behavioral /social science research tag; behavioral genetics; biological clocks; chromatin immunoprecipitation; circadian rhythms; cocaine; drug addiction; gel mobility shift assay; gene mutation; genetic transcription; laboratory mouse; neurochemistry; neuropharmacology; pharmacogenetics; reinforcer; substance abuse related behavior

DESCRIPTION (provided by applicant): Though drug addiction is one of the most prevalent and devastating diseases, still, relatively little is known about the molecular mechanisms that govern the long-term changes that occur in the brain that lead to addiction. It has been reported for some time that circadian rhythms are important in determining drug sensitivity and sensitization. More recently, studies have begun to emerge showing a more direct role for certain genes that make up the circadian clock in regulating not only drug-induced locomotor activity, but also the rewarding properties of drugs of abuse. This comprehensive study will examine the role of two of the primary transcription factors that make up the circadian clock, Clock and NPAS2, in regulating addiction-related behaviors. First, we will determine if cocaine (like methamphetamine) regulates the expresssion of these genes in specific regions of the brain known to be involved in drug reward. For behavioral and molecular studies, we have acquired mice that have functional knock-outs of Clock and NPAS2 and find that both mutations affect the rewarding properties of cocaine. These mice, along with mice that overexpress or knock-down these genes in specific brain regions through viral-mediated gene transfer, will be tested in a variety of behavioral paradigms to determine if mutation or overexpression of these genes leads to differences in addiction-related behaviors including self-administration, drug seeking and relapse. Finally, we will examine the molecular functions of Clock and NPAS2 to determine how they regulate two transcriptional target genes, mPerl and mPer2, that are involved in regulating drug-induced behaviors. We will determine the DMA binding at the promoters of these genes after drug exposure using gel shift analysis and ChIP, and determine if either Clock or NPAS2 are necessary to induce the Per genes after drug treatment. These studies will greatly enhance our understanding of the molecular changes that occur in the brain in response to drugs of abuse and how the circadian clock modulates drug addiction.

描述（由申请人提供）： 尽管吸毒是最普遍，最具破坏性的疾病之一，但仍然对控制导致成瘾的大脑中长期变化的分子机制相对较少了解。据报道，昼夜节律对于确定药物敏感性和敏感性很重要。最近，研究已经开始出现，显示出构成昼夜节律时钟不仅在调节药物诱导的运动活性的某些基因的更直接作用，而且还构成了滥用药物的奖励性能。这项全面的研究将研究构成昼夜节律时钟，时钟和NPAS2的两个主要转录因子在调节与成瘾相关的行为中的作用。首先，我们将确定可卡因（如甲基苯丙胺）是否调节已知参与药物奖励的大脑特定区域的这些基因的表达。对于行为和分子研究，我们获得了具有时钟和NPAS2功能性敲除的小鼠，发现这两个突变都会影响可卡因的奖励性能。这些小鼠以及通过病毒介导的基因转移在特定大脑区域过表达或敲除这些基因的小鼠将在各种行为范式中进行测试，以确定这些基因的突变或过表达是否会导致成瘾相关行为的差异，包括自我分配，吸毒，吸毒和复发。最后，我们将检查时钟和NPAS2的分子功能，以确定它们如何调节两个转录靶基因MPERL和MPER2，这些基因与调节药物诱导的行为有关。我们将使用凝胶移位分析和芯片在药物暴露后确定这些基因启动子的DMA结合，并确定在药物治疗后诱导每个基因的时钟或NPAS2是否需要。这些研究将大大增强我们对响应滥用药物以及昼夜节律如何调节药物成瘾的大脑中分子变化的理解。