Mechanistic studies of corepressor-mediated PPARγ transcriptional repression

辅阻遏物介导的 PPARγ 转录抑制的机制研究

• 批准号: 10830181
• 负责人: Douglas Kojetin
• 金额: $ 36.86万
• 依托单位: VANDERBILT UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-03-01 至 2024-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10830181
• 关键词: Mechanistic; studies; corepressor; mediated; PPAR; Mechanistic; studies; corepressor; mediated; PPAR

Peroxisome proliferator-activated receptor gamma (PPARγ) is a nuclear receptor transcription factor that regulates cellular differentiation, adipogenesis, and insulin resistance by recruiting transcriptional coregulator proteins (corepressor and coactivator proteins) to target gene promoters in a ligand-dependent manner. Structure-function approaches have defined how the transcriptionally active structural conformation and coactivator-selective functions of PPARγ are influenced by agonist ligands. However, little is known about the transcriptionally repressive conformation and corepressor-selective functions of PPARγ. Our long-term goal is to close this knowledge gap by defining how different pharmacological PPARγ ligands influence the structure and function of PPARγ between transcriptionally active and repressive states. In preliminary studies, we solved crystal structures of the PPARγ ligand-binding domain (LBD) in a transcriptionally repressive state using a unique corepressor-selective ligand, revealing a unique structural conformation that we have started to validate using solution NMR methods. In this project, we will use mechanistic studies to define how small molecule ligands impact PPARγ activation and repression on the molecular, structural, and cellular levels. Successful outcomes from our studies will define the activity-dependent conformational ensemble of the PPARγ LBD, develop ligands with enhanced corepressor-selective activity, and determine the molecular mechanisms by which corepressor-selective repressive ligands modulate PPARγ cellular functions.

过氧化物组增殖物激活的受体伽马（PPARγ）是一种核受体转录因子， 通过募集转录核心节目来调节细胞分化，脂肪生成和胰岛素抵抗 以配体依赖性方式靶向基因启动子的蛋白质（核心蛋白和共激活蛋白）。 结构功能方法已经定义了转录活跃的结构构象和 PPARγ的共激活者选择性功能受激动剂配体的影响。但是，关于 PPARγ的转录反射性考虑和核心选择性功能。我们的长期目标是 通过定义不同的药物PPARγ配体如何影响结构，来缩小这一知识差距 PPARγ在转录活性状态和反射状态之间的功能。在初步研究中，我们解决了 PPARγ配体结合结构域（LBD）在转录反射状态下使用A 独特的Corepressor选择配体，揭示了我们已经开始验证的独特结构构象 使用解决方案NMR方法。在这个项目中，我们将使用机械研究来定义小分子的方式 配体会影响PPARγ激活和反射对分子，结构和细胞水平。成功的 我们研究的结果将定义PPARγLBD的活动依赖性宪法合奏， 开发具有增强的核压球性活性的配体，并通过 哪种核心选择性反射配体调节PPARγ细胞功能。