Role of Nedd4-2, SGK1, and 14-3-3 in ENaC Trafficking

描述(由申请人提供)： 高血压(HTN)影响发达国家25%的成年人口，是中风、心肌梗死和充血性心力衰竭的主要独立危险因素。导致HTN的几个单基因缺陷现在被归因于对醛固酮敏感的远端肾单位内钠处理的异常，在那里，上皮性Na+通道ENaC构成了肾脏中Na+转运的限速步骤。因此，阐明ENaC的调控机制将对HTN的研究具有深远的病理生理学意义。拟议的研究将集中在Nedd4-2、SGK1和14-3-3蛋白在ENaC运输中的作用。拟议的实验旨在：(1)表征Nedd4-2调控ENaC运输的分子机制。(2)确定与Ned4-2相互作用并抑制Ned4-2的特异性14-3-3亚型(S)的亚细胞定位。(3)探讨SGK1和14-3-3调控Ned4-2的分子机制。 除了建议的实验外，细胞生物学、共聚焦显微镜和负责任的研究指导课程将补充结构化的导师培训计划，为首席研究员(PI)作为肾脏病临床科学家的学术生涯做准备。David Pearce博士是离子运输荷尔蒙调节领域的领导者，将指导PI的科学发展。此外，基思·莫斯托夫博士是上皮细胞细胞内运输领域的领导者，他将在实验设计和结果解释方面提供科学专业知识。由有成就的生物医学科学家组成的专业发展咨询委员会也将定期召开会议，提供科学和职业建议。加州大学旧金山分校提供的多样化的科学资源和结构化的指导是培训临床科学家的理想选择。在这种培训计划和环境中，PI将发展成为一名有竞争力的独立调查员。

DESCRIPTION (provided by applicant): Hypertension (HTN) affects 25% of the adult population in the developed world and is a major, independent risk factor for stroke, myocardial infarction, and congestive heart failure. Several monogenetic defects resulting in HTN have now been attributed to abnormalities in sodium handling within the aldosterone-sensitive distal nephron where the epithelial Na+ channel, ENaC, constitutes the rate-limiting step of Na+ transport in the kidney. Therefore, elucidating the mechanisms of ENaC regulation will have profound pathophysiologic implications for the study of HTN. The proposed research will focus on the role of Nedd4- 2, SGK1, and 14-3-3 proteins in ENaC trafficking. The proposed experiments aim to: (1) Characterize the molecilar mechanisms by which Nedd4-2 regulates trafficking of ENaC. (2) Determine the subcellular localization of the specific 14-3-3 isoform(s) which interact with and inhibit Nedd4-2. (3) Evaluate the molecular mechanism of SGK1 and 14-3-3 regulation of Nedd4-2. In addition to the proposed experiments, didactic coursework in cell biology, confocal microscopy, and the responsible conduct of research will complement a structured mentorship training program to prepare the principal investigator (PI) for an academic career as a clinical scientist in Nephrology. Dr. David Pearce is a leader in the field of hormone regulation of ion transport and will mentor the Pi's scientific development. Additionally, Dr. Keith Mostov is a leader in the field of intracellular trafficking in epithelial cells and will provide scientific expertise in the design of experiments and interpretation of results. A professional development advisory committee comprised of accomplished biomedical scientists will also convene at regular intervals to provide scientific and career advice. The diverse, scientific resources and structured mentoring available at UC San Francisco are ideal for training clinical scientists. Within this training program and environment the PI will develop into a competitive, independent investigator.