MOLECULAR ROLE OF RIGUI IN MAMMALIAN CIRCADIAN PATHWAY

描述：哺乳动物生物钟的分子组成如下 难以捉摸。申请人已经分离出一种名为RIGUI的人类基因，它编码 一种与果蝇周期基因44%同源的bHLH/PAS蛋白。 高度保守的小鼠同源基因(m-rigui)在昼夜节律中表达 视交叉上核(SCN)内的模式 哺乳动物的生物钟。SCN中的昼夜节律表达在 恒定的黑暗，光/暗周期的变化会引起成比例的 M-Rigui在SCN的表达发生移位。M-Rigui的记录也出现在 浦肯野神经元、结节部和视网膜的周期性模式，但 一种不同于在SCN中看到的振荡定时。给定 观察到RIGUI基因具有关于核心的所有已知属性 昼夜节律成分首席调查者想要更好地定义 它在昼夜节律途径中的确切作用。这项研究的具体目的 是为了：a)识别特定的大脑和周围组织，其中各种 昼夜节律振荡器存在；b)确定褪黑素是否在 M-Rigui在脑垂体部的表达；c)调查 M-Rigui在视网膜和视交叉上核表达的反应 对环境光线的提示；d)有针对性地破坏m-rigui 用基因敲除方法检测基因座，并确定其丢失对 动物的昼夜行为；e)识别编码蛋白质的基因 使用双混合系统与RIGUI交互；f)确定 人类RIGUI基因座的基因组结构及其启动子和 顺式作用元素。认识右归的遗传学和分子基础 功能可能导致关于基因如何控制哺乳动物的新范式 行为。

DESCRIPTION: The molecular components of mammalian circadian clocks are elusive. The applicant has isolated a human gene termed RIGUI that encodes a bHLH/PAS protein 44 percent homologous to the period gene in Drosophila. The highly conserved mouse homolog (m-rigui) is expressed in a circadian pattern in the suprachiasmatic nucleus (SCN), the master regulator of circadian clocks in mammals. Circadian expression in the SCN continues in constant darkness, and a shift in the light/dark cycle evokes a proportional shift of m-rigui expression in the SCN. m-rigui transcripts also appear in a periodic pattern in Purkinje neurons, pars tuberalis, and retina, but with a timing of oscillation different from that seen in the SCN. Given the observation that the RIGUI gene has all the properties known about a core circadian component the principal investigator would like to define better its exact role in the circadian pathway. The specific aims of this study are to: a) Identify specific brain and peripheral tissue where the various circadian oscillators reside; b) Determine whether melatonin plays a role in the expression of m-rigui in the hypophyseal pars-tuberalis; c) Investigate the response of m-rigui expression in the retina and suprachiasmatic nucleus to environmental light cues; d) Make the targeted disruption of the m-rigui locus by gene knock-out methodology and determine the effect of its loss on the circadian behavior of the animals; e) Identify genes encoding proteins that interact with RIGUI using the two-hybrid system; f) Determine the genomic structure of the human RIGUI locus and delineate its promoter and cis-acting elements. Understanding genetics and molecular basis of RIGUI function could lead to new paradigms on how genes control mammalian behavior.