Hypoxic Sensing Transcription Factor EPAS1 in Mice

描述(由申请人提供) 这项建议的总体目标是增加我们对 成年小鼠的低氧反应。PAS域家族的成员 转录因子在发育和应答中起着重要作用 环境压力，包括低氧反应。第一批被确认的 这个家族的低氧反应成员，低氧诱导因子I(HiFi)， 激活包括促红细胞生成素启动子在内的许多靶基因。 内皮PAS结构域蛋白1(EPAS1)，第二低氧反应成员 在血管内皮细胞中高水平表达， 颈动脉小体、球状细胞和肺泡细胞。尽管有这样的观察 HIF1和EPAS1可与相似DNA调控序列结合 启动子，HIF1和EPAS1可能发挥着不同的调节作用 从表达部位的差异以及阶段和 对各自基因敲除的胚胎致死性的描述。我们 假设EPAS1等低氧调节因子从根本上参与了 在高血压、睡眠呼吸暂停和心力衰竭的发病机制中。 本项目的具体目标是：(1)构建一个前置条件 用于产生EPAS1的条件敲除的菌株；(2)构建 解剖组织限制性表达cre的转基因小鼠 重叠EPAS1表达的位点；(3)产生缺乏EPAS1的基因敲除小鼠 在血管内皮细胞或血管球体细胞中表达，并表征其心血管功能 得到的EPAS1缺陷小鼠在常氧和间歇条件下 低氧状态。 首席调查员已完成内科住院医师培训， 在心脏病学方面获得奖学金，最近还在 生物化学系。他的博士研究涉及分子 艾滋病毒基因调控的生物学研究。他的博士后研究涉及 确定神经限制性转录因子的神经生物学作用 在老鼠击倒模型中。他最近刚被任命为助理 心脏科教授。拟开展的生理学研究 心血管功能方面的研究将导致获得研究 实验领域的技能对这位研究者来说是新奇的。他的赞助商和 咨询委员会成员将作为重要资源，因为他们 心血管生物学和其他直接相关领域的专业知识 对这些实验目标的追求。加拿大国际开发署的赠款将帮助 将首席调查员培养成独立的研究领导者 心血管生物学，其职业目标是研究信号转导 在成年哺乳动物的心血管系统中。

DESCRIPTION (provided by applicant) The overall goal of this proposal is to increase our understanding of the hypoxic response in the adult mouse. Members of the PAS domain family of transcription factors have important roles in development and in response to environmental stresses including hypoxic-responsiveness. The first identified hypoxic-responsive member of this family, hypoxia inducible factor I (HIFI), activates a number of target genes including the erythropoeitin promoter. Endothelial PAS domain protein 1 (EPAS1), the second hypoxic-responsive member of the PAS family, is expressed at high levels in vascular endothelial cells, carotid body glomus cells, and pulmonary pneumocytes. Despite the observation that HIF1 and EPAS1 can bind to similar DNA regulatory sequences in model promoters, it is likely that HIF1 and EPAS1 play distinctive regulatory roles as evident by the differences in sites of expression as well as stage and description of embryonic lethality for the respective knockouts. We hypothesize that hypoxic regulators such as EPAS1 are fundamentally involved in the pathogenesis underlying hypertension, sleep apnea, and heart failure. The specific aims of this project are to: (1) construct a preconditional strain for use in generating conditional knockouts for EPAS1; (2) construct transgenic mice that express cre in a tissue-restricted manner in anatomic sites that overlap EPAS1 expression; (3) generate knockout mice lacking EPAS1 in endothelial or glomus cells and characterize the cardiovascular function of the resultant EPAS1- deficient mice under normoxic as well as intermittent hypoxic conditions. The principal investigator has completed a residency in internal medicine, a fellowship in cardiology, and most recently a postdoctoral fellowship in the department of biochemistry. His doctoral research involved molecular biological studies of HIV gene regulation. His postdoctoral research involved defining the neurobiological role of a neural-restricted transcription factor in a mouse knockout model. He has just recently been appointed an assistant professor in the cardiology division. The proposed research on physiologic aspects of cardiovascular function will result in the acquisition of research skills in experimental areas novel to this investigator. His sponsors and advisory committee members will serve as important resources due to their expertise in cardiovascular biology and in other areas directly relevant to the pursuit of these experimental aims. The CIDA grant would aid in development of the principal investigator into an independent research leader in cardiovascular biology whose career goals are to study signal transduction in the adult mammalian cardiovascular system.