The identification and characterization of a novel circadian ETS factor

项目摘要 本申请为美国国家糖尿病与消化研究所授予的博士后奖学金。 向内科科学家实习生介绍肾脏疾病。申请人为医学科学家培训实习生 宾夕法尼亚大学佩雷尔曼医学院的项目。这个奖将对他有帮助。 实现他的职业目标，成为一名研究昼夜节律在 新陈代谢。昼夜节律是调节人类方方面面的生物钟 生理学。昼夜节律失调在现代社会中很普遍，也是导致 肥胖症和糖尿病在美国和世界范围内的流行不断上升。为了支持这一点，许多流行病学 研究表明，上夜班的人更有可能有更高的BMI，更容易患上 发展代谢性疾病，如肥胖、糖尿病和相关的心血管并发症。虽然这件事 是一个日益重要的紧迫的公共卫生问题，我们仍然缺乏机械性的认识 生物钟与新陈代谢的关系。为了更好地理解分子 昼夜节律与代谢动态平衡的联系机制，我们的实验室进行了一项全基因组研究 描述肝脏转录是如何以昼夜节律的方式调节的。令人欣慰的是，我们发现了几个 已知的协调特定转录昼夜节律阶段的转录因子，如REV-ERBα和 BMal1.有趣的是，我们的功能基因组数据预测，ETS家族的一种转录因子 在7AM-10AM调节转录的昼夜节律阶段然而，没有已知的ETS因素表现出来 以昼夜节律的方式。在这项提案中，我提供了初步的蛋白质组和基因组数据，表明 GABPα是一种昼夜节律转录因子，在线粒体的生物发生和代谢中具有潜在的作用 动态平衡。这一发现提出了关于GABPα如何协调昼夜节律的两个机械性问题 GABPα转录及其在肝脏代谢中的功能作用。对于目标1，我将剖析分子 用遗传功能丧失方法研究GABPα对昼夜节律转录调控的机制 无偏见的蛋白质组学方法。对于目标2，我将确定GABPα在肝脏中的生理作用 通过测量生理和代谢参数并进行功能代谢分析来进行代谢， 最终将分子、细胞和代谢变化与生理结果联系起来。这些一体化的 实验将确定之前未知的GABPα在转录调控中的昼夜节律作用 和肝脏新陈代谢。此外，从这一提议中获得的新奇见解将既具有机械性 以及昼夜节律失调如何导致代谢功能障碍的治疗意义。

Project Summary This application is for a predoctoral fellowship awarded by the National Institute of Diabetes and Digestive and Kidney Diseases to physician-scientist trainees. The applicant is a trainee of the Medical Scientist Training Program at the Perelman School of Medicine at the University of Pennsylvania. This award would help him achieve his career goal of becoming a physician-scientist investigating the role of circadian rhythms in metabolism. Circadian rhythms are biological clocks that regulate all-encompassing aspects of human physiology. Circadian misalignment is prevalent in the modern society and one of the contributing factors to the rising epidemics of obesity and diabetes in the U.S. and worldwide. In support of this, many epidemiological studies have demonstrated that night shift workers are more likely to have higher BMI and more prone to developing metabolic diseases such as obesity, diabetes, and related cardiovascular comorbidities. While this is an imperative public health issue with increasing significance, we still lack a mechanistic understanding of the relationship between the circadian clock and metabolism. In efforts to better understand the molecular mechanisms linking circadian rhythms to metabolic homeostasis, our lab has undertaken a genome-wide study characterizing how hepatic transcription is regulated in a circadian manner. Reassuringly, we identified several transcription factors known to coordinate specific circadian phases of transcription, such as Rev-erbα and Bmal1. Interestingly, our functional genomic data predicted that a transcription factor from the ETS family regulates a circadian phase of transcription at 7 AM-10 AM. However, there is no ETS factor known to behave in a circadian manner. In this proposal, I provide preliminary proteomic and genomic data suggesting that GABPα is the circadian ETS transcription factor, with potential roles in mitochondrial biogenesis and metabolic homeostasis. This finding raises both mechanistic questions about how GABPα coordinates circadian transcription and the functional role of GABPα in hepatic metabolism. For Aim 1, I will dissect the molecular mechanism of circadian transcriptional control by GABPα using a genetic loss-of-function approach and an unbiased proteomics approach. For Aim 2, I will determine the physiological role of GABPα in hepatic metabolism by measuring physiologic and metabolic parameters and performing functional metabolic assays, ultimately to link molecular, cellular, and metabolic changes with physiological outcomes. These integrative experiments will determine the previously unrecognized circadian role of GABPα in transcriptional regulation and hepatic metabolism. Furthermore, the novel insights gained from this proposal will have both mechanistic and therapeutic implications for how circadian misalignment leads to metabolic dysfunction.