Translational regulation of PGC1alpha and oxidative metabolism

项目摘要 随着肥胖症和相关疾病的患病率上升，操纵脂肪细胞能量消耗已经成为一种新的方法。 作为治疗代谢性疾病的潜在手段而受到关注。这种策略利用了 产热脂肪细胞，一种依赖于氧化磷酸化代谢来驱动无用化学物质的细胞类型， 以热的形式释放能量的循环。最近的工作表明，核糖体控制的潜力， 产热基因表达阐明责任机制可能会揭示新的手段来操纵 用于治疗肥胖症和糖尿病的脂肪细胞代谢。这一提议检验了以下假设： 产热脂肪的独特代谢是由这种基因中固有的专门的mRNA翻译偏好实现的。 细胞类型。第一组研究集中在单个mRNA，PPARGC 1A，目的是纯化蛋白质， 赋予其细胞类型特异性翻译输出。该mRNA编码PGC 1 α，PGC 1 α是一种主要的调节因子 线粒体生物发生第二组研究开发了一种体内小鼠模型来测试以下假设： 解旋酶DDX3X是mRNA翻译和细胞质应激颗粒的调节剂，是一种产热脂肪酶， 支持氧化代谢关键基因表达的选择性翻译调节因子。第三组 的研究使用核糖体分析技术来定义与以下相关的全球mRNA翻译动力学： 产热活化总之，这些研究扩大了我的工作范围，同时产生了基础性的 数据集和老鼠模型来保证我的科学独立性。他们将在一个公认的实验室进行， 达纳-法伯癌症研究所的分子代谢领域的领导者布鲁斯斯皮格曼博士， 哈佛医学院。在这个丰富的环境中，我将受益于一个致力于指导 我在：脂肪细胞生物学，包括在体内遗传操作;小鼠代谢表型;质量 光谱学和生物信息学。技术培训还辅之以正式的人文教育。 代谢病理生理学，以及磨练我的领导能力，演讲和写作技巧的活动。在这 NIH独立之路奖支持我从指导工作过渡到独立工作的方式 在这个阶段，我打算使用尖端的方法来广泛定义的翻译动力学 产热脂肪，确定负责任的监管机构，并测试如何转录后动力学，如压力 颗粒组装可能起作用。我的最终目标是领导一个学术研究小组， 定义细胞身份和代谢的基因表达程序是如何建立的， 以及如何在治疗上操纵它们以预防或治疗代谢性疾病。 疾病

PROJECT SUMMARY As the prevalence of obesity and associated disorders rises, manipulation of adipocyte energy expenditure has gained attention as a potential means to treat metabolic disease. This strategy leverages the physiology of thermogenic adipocytes, a cell type that relies on oxidative phosphorylation metabolism to drive futile chemical cycles that release energy as heat. Recent work has suggested the potential for ribosomal control of thermogenic gene expression. Elucidating the responsible mechanisms may reveal novel means to manipulate adipocyte metabolism for the treatment of obesity and diabetes. This proposal tests the hypothesis that the distinct metabolism of thermogenic fat is enabled by specialized mRNA translation preferences inherent in this cell type. A first set of studies focuses on a single mRNA, PPARGC1A, and aims to purify the proteins that confer its cell-type-specific translational output. This mRNA encodes PGC1α, a dominant regulator of mitochondrial biogenesis. A second set of studies develops an in vivo mouse model to test the hypothesis that the helicase DDX3X, a regulator of mRNA translation and cytoplasmic stress granules, is a thermogenic-fat- selective translational regulator that supports expression of genes critical for oxidative metabolism. A third set of studies uses ribosome profiling technology to define the global mRNA translation dynamics associated with thermogenic activation. Together, these studies expand the scope of my work while generating foundational datasets and mouse models for my scientific independence. They will be carried out in the lab of a recognized leader in the field of molecular metabolism, Dr. Bruce Spiegelman, at the Dana-Farber Cancer Institute and Harvard Medical School. In this rich environment, I will benefit from a mentorship team committed to instruct me in: adipocyte biology, including in vivo genetic manipulation; mouse metabolic phenotyping; mass spectrometry; and bioinformatics. The technical training is complemented by formal instruction in human metabolic pathophysiology, as well as activities for honing my leadership, speaking, and writing skills. In this way the NIH Pathway to Independence Award supports my transition from mentored work to an independent stage in which I intend to use cutting-edge methods to broadly define the translational dynamics of thermogenic fat, identify the responsible regulators, and test how post-transcriptional dynamics such as stress granule assembly may contribute. My ultimate goal is to lead an academic research group that investigates how the gene expression programs that define cellular identity and metabolism are established, how they are perturbed in metabolic disease, and how they may be therapeutically manipulated to prevent or treat metabolic disease.