Obesity and diabetes genetics and therapeutics in Caenorhabditis elegans.

描述(由申请者提供)：这项博士后研究计划概述了利用秀丽隐杆线虫来识别与肥胖和糖尿病发病相关的基因的计划。肥胖症和2型糖尿病是极其普遍的、高度相关的疾病，2002年美国花费了超过1320亿美元，并在生命年损失方面给社会造成了更大的代价。具体目的是利用基因组学(RNA干扰)和正向遗传学以及新可用的高通量技术对新基因进行饱和筛选，这些基因在失活时会导致体内脂肪含量或线粒体生物发生的神经内分泌调节缺陷。由于脂肪代谢失调和线粒体功能障碍都明显与II型糖尿病的发病机制有关，因此从与人类密切同源的筛查中出现的基因将是进一步研究的主题。由于许多在人类糖尿病中重要的已知基因在线虫中发生突变时也会导致衰老、抗应激或生殖缺陷，因此将对每个被确定为影响脂肪或线粒体的新基因进行这些多向性分析。在这些检测中获得优先分数的突变体将具有能量稳态缺陷，具体特征是脂肪含量、食物消耗和能量消耗的定量分析。基因上位性将确定哪些基因在调节能量动态平衡的已知途径或新途径中起作用。将通过转基因报告基因和组织特异性救援构建来确定感兴趣基因的组织表达和细胞类型。对于最有希望的脂肪和线粒体突变，将利用串联质谱仪进行代谢组谱分析和微阵列mRNA谱分析，以进一步探索代谢缺陷的分子本质。最后，为了确定可能的肥胖或糖尿病治疗方法，将对小分子文库进行筛选，以寻找逆转突变表型的化合物，即肥胖或线粒体缺陷。这项工作的最终目标是识别和表征肥胖和糖尿病发病机制的核心基因，识别可能的治疗分子，并创建一个在未来扩大这些努力的平台。 公共卫生相关性：肥胖症和2型糖尿病是紧密联系在一起的疾病，被公认为是导致过早患病和死亡的主要原因之一。全球有超过10亿人超重，超过2亿人患有糖尿病。拟议的研究奖学金旨在利用新技术和一种可以系统研究每一个基因的作用的遗传系统，确定与肥胖和糖尿病的发展有关的新基因，以及可能抗击这些毁灭性疾病的药物。

DESCRIPTION (provided by applicant): This postdoctoral fellowship proposal outlines plans to use the organism Caenorhabditis elegans to identify genes involved in the pathogenesis of obesity and diabetes. Obesity and type 2 diabetes are extremely prevalent, highly associated diseases that cost the US more than $132 billion in 2002, and produce an even greater cost on society in terms of life-years lost. Specific aims are to use genomics (RNA interference) and forward genetics together with newly-available, high-throughput technology to perform saturating screens for novel genes which, when inactivated, cause defects in neuroendocrine regulation of body fat content or mitochondrial biogenesis. Genes emerging from the screens with close human homologues will be the subject of further study, since both dysregulated fat metabolism and mitochondrial dysfunction have been clearly implicated in the pathogenesis of type II diabetes. As many known genes important in human diabetes also cause aging, stress resistance or reproductive defects when mutated in C. elegans, assays for these pleiotropies will be conducted for each novel gene identified to affect fat or mitochondria. Mutants receiving priority scores in these assays will have energy homeostasis defects characterized in detail by quantitative assays for lipid content, food consumption, and energy expenditure. Genetic epistasis will identify which genes operate within known pathways or novel pathways regulating energy homeostasis. The tissue of expression and cell type of action will be established for interesting genes by transgenic reporter and tissue-specific rescue constructs. For the most promising fat and mitochondrial mutants, metabolomic profiling using tandem mass spectrometry and microarray mRNA profiling analysis will be conducted to further explore the molecular nature of metabolic defects. Finally, in order to identify possible obesity or diabetes therapeutics, a small-molecule library will be screened for compounds that reverse mutant phenotypes, i.e. obesity or mitochondrial defects. The ultimate goals of this work are to identify and characterize genes central to the pathogenesis of obesity and diabetes, to identify possible therapeutic molecules, and to create a platform to expand these efforts in the future. PUBLIC HEALTH RELEVANCE: Obesity and type 2 diabetes are tightly linked diseases well recognized to be among the leading causes of premature illness and death. Over one billion people are overweight and more than 200 million have diabetes worldwide. The proposed research fellowship aims to identify novel genes involved in the development of obesity and diabetes and possible drugs to fight these devastating diseases, using new technology and a genetic system in which the role of every single gene can be studied systematically.