Epigenomic Regulation of Gene Expression in Diet Induced Obesity

饮食引起的肥胖基因表达的表观基因组调控

• 批准号: 8317601
• 负责人: David Gerard Peters
• 金额: $ 18.94万
• 依托单位: UNIVERSITY OF PITTSBURGH AT PITTSBURGH
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-08-15 至 2014-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8317601
• 关键词: Adult; Affect; Base Sequence; Bioinformatics; Biological Assay; Cardiovascular Diseases; Chronic; DNA; DNA Methylation; DNA Sequence; Data; Defect; Development; Diabetes Mellitus; Diet; Disease; Energy Metabolism; Environment; Epidemic; Epigenetic Process; Exposure to; Fatty acid glycerol esters; Gene Expression; Gene Expression Profile; Gene Expression Regulation; Genes; Genetic; Genetic Predisposition to Disease; Genetic Transcription; Genome; Hepatic; Histones; Individual; Lead; Life; Life Style; Liver; Malnutrition; Measures; Mediating; Messenger RNA; Metabolic; Metabolic syndrome; Methods; Methylation; Molecular; Non-Insulin-Dependent Diabetes Mellitus; Nuclear; Nutrient; Obesity; Overnutrition; Pathway interactions; Phenotype; Play; Post-Translational Protein Processing; Regulation; Resolution; Reverse Transcriptase Polymerase Chain Reaction; Role; Run-On Assays; Running; Sampling; Techniques; Testing; Tissues; United States; Validation; chromatin immunoprecipitation; epigenomics; follow-up; gene environment interaction; genome-wide; genome-wide analysis; mature animal; molecular phenotype; next generation; novel; obesity risk; offspring; sedentary; tool; transcription factor

DESCRIPTION (provided by applicant): Obesity and its related disorders, including type 2 diabetes mellitus, metabolic syndrome, and cardiovascular disease, have reached epidemic levels in the United States. While genetic predisposition provides a background for the expression of acquired metabolic defects in obesity and type 2 diabetes, the majority of these metabolic defects become apparent only through energy imbalance, that is, energy oversupply and/or decreased energy expenditure. Therefore, gene- environment interactions are significant in the development of these diseases and there is increasing evidence that these effects are mediated biologically at the level of epigenetics, a spectrum of largely sequence-independent regulatory influences on gene expression including DNA methylation. Epigenetic influences on phenotype are perhaps best exemplified by recent studies demonstrating that the intrauterine environment, either malnutrition or overnutrition, influences gene expression through differential methylation of genes that lead to an altered metabolic phenotype that increases the risk for obesity and obesity-related disorders in the offspring. However, very little is known about the potential for epigenetic regulation of energy metabolism and obesity in adult life. An intriguing possibility is that chronic exposure to an environment that predisposes people to obesity and diabetes, such as a high fat Western diet and sedentary lifestyle, leads to altered DNA methylation and altered phenotype of metabolically active tissues. The liver is central to metabolic regulation and, as the key distributor of most ingested nutrients due to its anatomical proximity to the gut, is an ideal candidate for testing epigenetic changes from overnutrition. We propose to test the hypothesis that the development of obesity in adulthood alters gene expression and energy metabolism in the liver at least partially through changes in DNA methylation. Aim 1 is perform a quantitative genome-wide analysis of the hepatic DNA methylome following exposure to a high fat diet, which will be accomplished using Methyl-Sensitive Cut Counting (MSCC). Aim 2 is to perform a quantitative genome-wide analysis of the hepatic transcriptome following exposure to a high-fat diet, which will be accomplished using genome-wide 5' SOLID-SAGE. Aim 3 is to determine mechanistic relationships between DNA methylation and gene expression, which will be accomplished using state of the art computational approaches to identify genes that are both differentially methylated and expressed, and then selected genes will be validated with qRT-PCR and single gene methylation analysis. Finally mechanistic relationships between transcription factor recruitment and transcriptional rate will be determined by chromatin immunoprecipitation and nuclear run-on. This project has the potential to provide groundbreaking information concerning the epigenetics of obesity.

描述（由申请人提供）：肥胖及其相关疾病，包括2型糖尿病、代谢综合征和心血管疾病，在美国已达到流行水平。虽然遗传易感性为肥胖和2型糖尿病中获得性代谢缺陷的表达提供了背景，但这些代谢缺陷中的大多数仅通过能量不平衡变得明显，即能量供应过剩和/或能量消耗减少。因此，基因-环境相互作用在这些疾病的发展中是重要的，并且有越来越多的证据表明，这些作用在表观遗传学水平上是生物学介导的，表观遗传学是对基因表达的一系列基本上不依赖于序列的调控影响，包括DNA甲基化。表观遗传对表型的影响可能最好的例证是最近的研究表明，宫内环境，营养不良或营养过剩，通过基因的差异甲基化影响基因表达，导致代谢表型改变，增加后代肥胖和肥胖相关疾病的风险。然而，很少有人知道的能量代谢和肥胖在成年生活中的表观遗传调控的潜力。一个有趣的可能性是，长期暴露于易使人患肥胖症和糖尿病的环境，如高脂肪的西方饮食和久坐不动的生活方式，导致DNA甲基化改变和代谢活性组织的表型改变。肝脏是代谢调节的中心，并且由于其解剖学上接近肠道，作为大多数摄入营养素的主要分配者，是测试营养过剩引起的表观遗传变化的理想候选者。我们建议测试这一假设，即成年期肥胖的发展至少部分通过DNA甲基化的变化改变了肝脏中的基因表达和能量代谢。目的1是对高脂饮食暴露后的肝DNA甲基化组进行全基因组定量分析，这将使用甲基敏感切割计数（MSCC）来完成。目的2是在暴露于高脂饮食后对肝转录组进行全基因组定量分析，这将使用全基因组5' SOLID-SAGE完成。目的3是确定DNA甲基化和基因表达之间的机制关系，这将使用最先进的计算方法来鉴定差异甲基化和表达的基因，然后用qRT-PCR和单基因甲基化分析来验证所选基因。最后，转录因子募集和转录速率之间的机制关系将通过染色质免疫沉淀和核run-on来确定。