Genomic determinants of leptin expression

瘦素表达的基因组决定因素

• 批准号: 7295192
• 负责人: Evan D Rosen
• 金额: $ 21.25万
• 依托单位: BETH ISRAEL DEACONESS MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-09-01 至 2009-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7295192
• 关键词: Address; Adipocytes; Adipose tissue; Affect; Antithymoglobulin; Area; Binding Proteins; Bone Density; Cells; Chromatin; Clinical; Collection; Complement; Data; Deoxyribonuclease I; Deoxyribonucleases; Desire for food; Electrophoretic Mobility Shift Assay; Elements; Employee Strikes; Endocrine Glands; Engineering; Exhibits; Fluorescence; Gene Expression; Gene Transfer Techniques; Genes; Genetic; Genomics; Goals; Histone Acetylation; Histones; Hormones; Hypersensitivity; Indium; Leptin; Lipodystrophy; Lysine; Maps; Mass Spectrum Analysis; Messenger RNA; Methylation; Modification; Mus; Non-Insulin-Dependent Diabetes Mellitus; Nutritional; Obesity; Organ; Pathway interactions; Physiological Processes; Play; Process; Proteins; RNA Interference; Range; Reporter; Reproduction; Role; Screening procedure; Signal Transduction; Site; Specific qualifier value; Testing; Therapeutic; Tissues; Trans-Activators; Transcript; Transgenes; Transgenic Mice; Transgenic Organisms; adipokines; adiponectin; base; blood glucose regulation; chromatin immunoprecipitation; glucose tolerance; immune function; in vitro Model; in vivo; innovation; innovative technologies; insight; interest; research study; small hairpin RNA; success; transcription factor

DESCRIPTION (provided by applicant): The enormous impact of obesity and type 2 diabetes demands that we develop a better understanding of how nutritional signals are interpreted and integrated by metabolically active tissues. In particular, there is newfound appreciation that adipose tissue serves as an endocrine organ with responsibility for coordinating a wide range of homeostatic mechanisms. The first of the adipose-derived hormones (the so-called 'adipokines') to be discovered was leptin, encoded by the Lep gene in a more or less adipose-selective manner. Leptin is now known to serve an adipostatic role by regulating appetite, and also plays a major role in glucose homeostasis, immune function, reproduction, and bone density. Raising leptin levels is a useful therapeutic strategy in lipodystrophy and in some genetic forms of obesity, and may be helpful in a subset of common obesity. Despite these clinical implications and the enormous amount of basic scientific interest in leptin, virtually nothing is known about the transcriptional pathways that regulate leptin mRNA synthesis. Here we propose several innovative approaches to solving this longstanding problem. For example, we have used BAC transgenesis to perform gross mapping of the regions required for adipocyte-selective Lep expression with great success. The first Aim uses additional rounds of BAC transgenesis to further reduce the target area. The second Aim allows fine mapping of critical cis regions through high- throughput DNase hypersensitivity mapping, chromatin immunoprecipitation of modified histone, and electrophoretic mobility shift assays. The third Aim is directed at identifying trans-acting factors that affect Lep expression through a limited RNAi screen in Lep reporter cells. Taken together, these studies will provide enormous insight into the transcriptional basis of Lep adipocyte expression. Leptin is an adipocyte-derived hormone with profound effects on appetite and glucose tolerance, in addition to effects on other physiological processes including bone density, reproduction, and immune function. Despite a decade of intensive study, there are virtually no data on the critical transcriptional pathways that regulate leptin synthesis. This proposal uses a variety of innovative technologies to address this deficit, including BAC transgenesis, high-throughput DNase hypersensitivity analysis, and shRNA screening.

描述（由申请人提供）：肥胖和2型糖尿病的巨大影响要求我们更好地了解如何通过代谢活性组织解释和整合营养信号。特别是，有新发现的欣赏是脂肪组织是一种内分泌器官，负责协调各种稳态机制。发现的第一种脂肪衍生的激素（所谓的“脂肪因子”）是瘦素，由LEP基因或多或少地以脂肪选择性方式编码。现在已知瘦素通过调节食欲来发挥脂肪作用，并且在葡萄糖稳态，免疫功能，繁殖和骨密度中也起着重要作用。升高瘦素水平是脂肪营养不良和某些遗传形式的肥胖症中有用的治疗策略，可能有助于一部分共同肥胖。尽管这些临床意义以及瘦素中的巨大科学兴趣，但实际上对调节瘦素mRNA合成的转录途径几乎一无所知。在这里，我们提出了一些创新的方法来解决这个长期存在的问题。例如，我们使用BAC转基因进行了脂肪细胞选择性LEP表达所需区域的总映射，并取得了巨大的成功。第一个目的使用其他回合的BAC转基因来进一步减少目标区域。第二个目的允许通过高吞噬DNase超敏反应，修饰组蛋白的染色质免疫沉淀和电泳迁移率转移测定法对关键的顺式区域进行精细映射。第三个目的是鉴定通过LEP报告基细胞中有限的RNAi屏幕影响LEP表达的反式作用因子。综上所述，这些研究将为LEP脂肪细胞表达的转录基础提供深刻的了解。瘦素是一种脂肪细胞衍生的激素，对食欲和葡萄糖耐受性具有深远影响，除了对包括骨密度，繁殖和免疫功能在内的其他生理过程的影响。尽管进行了十年的深入研究，但几乎没有关于调节瘦素合成的关键转录途径的数据。该建议使用各种创新技术来解决这一缺陷，包括BAC转基因，高通量DNase超敏反应分析和SHRNA筛查。