Genome-wide epigenetic control of circadian metabolism by heme receptor Rev-erb

血红素受体 Rev-erb 对昼夜节律代谢的全基因组表观遗传控制

• 批准号: 7817388
• 负责人: MITCHELL A. LAZAR
• 金额: $ 50万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-19 至 2011-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7817388
• 关键词: Address; Adipocytes; Adipose tissue; Affect; Antibodies; Area; Binding; Biology; Candidate Disease Gene; Circadian Rhythms; Cues; DNA; Data; Data Set; Diabetes Mellitus; Eating; Epidemic; Epigenetic Process; Fasting; Fatty acid glycerol esters; Gene Targeting; Genes; Genetic Transcription; Genome; Genomics; Goals; Laboratories; Leptin; Link; Liver; Liver Extract; Location; Mediating; Metabolic; Metabolic Control; Metabolic Diseases; Metabolism; Molecular; Mus; Nuclear Receptors; Obesity; Pathway interactions; Pattern; Physiological Processes; Physiology; Plasminogen Activator Inhibitor 1; Proteins; Regulation; Role; Signal Transduction; Sleep; Testing; Time; Tissues; Treatment Protocols; United States; adipokines; base; chromatin immunoprecipitation; feeding; genome wide association study; genome-wide; genome-wide analysis; glucose metabolism; heme receptor; in vivo; insight; mRNA Expression; mouse genome; promoter; public health relevance; research study; resistin; shift work

DESCRIPTION (provided by applicant): This application addresses the broad Challenge Area (08) Genomics and specific Challenge Topic 08-DK-107: Nuclear Receptor mediated assembly of functional transcriptional units. A major goal of this laboratory is to understand the transcriptional mechanisms by which nuclear receptors (NRs) regulate circadian and metabolic physiology. The heme receptor Rev-erb was identified by the PI in 1989, and has since emerged as an important repressor of key genes controlling circadian rhythm and glucose metabolism. Prior studies of Rev- erb have been based on candidate gene approaches focused on promoters. Thus, it is not surprising that only about ten Rev-erb-target genes are known, given that genome-wide location analyses for other nuclear receptors have revealed that most binding occurs outside of promoters. We hypothesize that Rev-erb functions through binding of hundreds of genes, many tissue-specifically. To address this, we will perform a genome-wide analysis of Rev-erb binding in mouse liver and white adipose tissues. Specific Aim 1 is to identify Rev-erb gene targets on a genome-wide scale in liver at different circadian times, and understand their modes of regulation. We hypothesize that circadian fluctuation of Rev-erb protein level will affect its ability to access recognition sequences in the genome, which, in turn, will have downstream effects on circadian and metabolic processes. We will test this by genome-wide location analysis using chromatin immunoprecipitation (ChIP) followed by sequencing of the isolated DNA (ChIP-seq). Specific Aim 2 is to identify Rev-erb gene targets on a genome-wide scale in liver from fed versus fasted mice and from mice under restricted feeding, and understand their modes of regulation. We hypothesize that metabolic regulation of Rev-erb activity will alter Rev-erb binding at many genes, and will test this by ChIP- seq using liver isolated from fed and fasted mice. Preliminary data reveal that Rev-erb protein level is higher in liver from fasted mice than in liver from fed mice, suggesting that Rev-erb binding activity may be modulated by metabolic signals. Specific Aim 3 is to identify Rev-erb gene targets on a genome-wide scale in white adipose tissue, and understand their modes of regulation. We hypothesize that Rev-erb mediates circadian expression of adipocyte genes and will test this by performing ChIP-seq for adipose Rev- erb at different circadian times and feeding regimens. This will expand our understanding of Rev-erb function in adipose biology and, when combined with the liver data set, it will identify tissue-specific targets and functions for Rev-erb in liver and adipose tissues. These studies can be accomplished in a two-year time frame because we have validated antibodies for ChIP of endogenous Rev-erb in metabolic tissues, and the experimental paradigms involve short-term studies. The genome-wide insights into in vivo tissue-specific regulation of circadian and metabolic genes will be enormous, and contribute greatly to our understanding of how these physiological processes are interrelated, and potentially dysregulated in obesity and diabetes, which are epidemic in the United States. PUBLIC HEALTH RELEVANCE: Metabolic disorders such as diabetes and obesity are affected by sleep patterns and shift work. Thus, it is exciting that the focus of this proposal, the nuclear receptor Rev-erb, has emerged as a critical link between circadian and metabolic physiology. The proposed experiments aim to determine the extent that Rev-erb contributes to, or even controls, circadian and metabolic processes and the crosstalk that occurs between them. Ultimately, greater insight into the regulation of circadian rhythm and metabolism by Rev-erb will contribute greatly to our understanding of how these physiological processes are interrelated, and potentially dysregulated in obesity and diabetes, which are epidemic in the United States.

描述（由申请人提供）：此申请介绍了广泛的挑战领域（08）基因组学和特定挑战主题08-DK-107：核受体介导的功能转录单元的组装。该实验室的主要目标是了解核受体（NRS）调节昼夜节律生理学的转录机制。 PI在1989年通过PI鉴定出血红素受体REV-ERB，此后已成为控制昼夜节律和葡萄糖代谢的关键基因的重要阻遏物。先前对ReverB的研究基于候选基因方法的重点是启动子。因此，毫不奇怪，只有大约十个Rev-erb-target基因是众所周知的，鉴于其他核受体的全基因组位置分析表明，大多数结合发生在启动子之外。我们假设Rev-ERB通过数百个基因的结合，许多组织特定于特定于此。为了解决这个问题，我们将对小鼠肝脏和白脂肪组织中的Rev-ERB结合进行全基因组的分析。具体目的1是在不同的昼夜节律时期识别肝脏全基因组量表上的Rev-ERB基因靶标，并了解其调节模式。我们假设Rev-ERB蛋白水平的昼夜节律波动将影响其访问基因组中识别序列的能力，这反过来又将对昼夜节律和代谢过程产生下游影响。我们将使用染色质免疫沉淀（CHIP）通过全基因组的位置分析进行测试，然后对分离的DNA（CHIP-SEQ）进行测序。具体目的2是在肝脏中与禁食小鼠和受限制喂养的小鼠的肝脏中的Rev-ERB基因靶标确定肝脏中的Rev-ERB基因靶标，并了解其调节模式。我们假设Rev-ERB活性的代谢调节会改变许多基因的Rev-ERB结合，并将使用从FED和禁食小鼠中分离出的肝脏对此进行测试。初步数据表明，禁食小鼠的肝脏Rev-ERB蛋白水平高于FED小鼠的肝脏，这表明Rev-ERB结合活性可能通过代谢信号调节。具体目的3是在白色脂肪组织中以全基因组规模鉴定Rev-ERB基因靶标，并了解其调节模式。我们假设Rev-erb介导脂肪细胞基因的昼夜节律表达，并将通过在不同的昼夜节律时期和喂养方案进行脂肪seq进行脂肪seq进行测试。这将扩展我们对脂肪生物学Rev-ERB功能的理解，并与肝脏数据集结合使用，它将确定组织特异性的靶标和肝脏和脂肪组织中Rev-ERB的功能。这些研究可以在两年的时间范围内完成，因为我们已经验证了代谢组织中内源性REV-ERB芯片的抗体，并且实验范式涉及短期研究。全基因组对昼夜节律和代谢基因调节的体内组织特异性调节的见解将是巨大的，并极大地有助于我们对这些生理过程如何相互关联的理解，并且在肥胖和糖尿病中可能失调，这在美国流行。 公共卫生相关性：糖尿病和肥胖症等代谢疾病受睡眠方式和转移工作的影响。因此，令人兴奋的是，该提案的重点，即核受体Rev-ERB，已成为昼夜节律与代谢生理学之间的关键联系。提出的实验旨在确定Rev-ERB对昼夜节律和代谢过程以及它们之间发生的串扰的贡献或什至控制的程度。最终，对Rev-ERB对昼夜节律的调节和代谢的调节将有更大的了解将极大地理解我们对这些生理过程如何相互关联的方式，并且可能在肥胖和糖尿病中失调，这些过程在美国流行。