Molecular Analysis of a Yeast Transcriptional Regulator

酵母转录调节因子的分子分析

• 批准号: 7911437
• 负责人: David T. Auble
• 金额: $ 19.77万
• 依托单位: UNIVERSITY OF VIRGINIA
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-09 至 2012-02-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7911437
• 关键词: ATP Hydrolysis; ATP phosphohydrolase; Address; Affect; Architecture; Area; Binding; Biochemical; Biological; Biological Assay; Cells; Chromatin; Cockayne Syndrome; Complex; DNA; Defect; Development; Dissociation; Ensure; Enzymes; Family; FeBABE; Generations; Genes; Genetic; Genetic Transcription; Growth; Heterogeneity; Human; In Vitro; Individual; Lead; Malignant Neoplasms; Mechanics; Mediating; Metabolism; Modeling; Molecular; Molecular Analysis; Molecular Mechanisms of Action; Mutation; Nuclear; Play; Positioning Attribute; Protein Binding; Protein Dynamics; Proteins; Quality Control; RNA analysis; Reaction; Recycling; Research Personnel; Role; SAGA; Saccharomyces cerevisiae; Saccharomycetales; Signal Transduction; Site; Staging; TATA-Box Binding Protein; Testing; Thalassemia; Transcriptional Activation; Transcriptional Regulation; Work; X-Linked Mental Retardation; Yeasts; analog; base; genome-wide; histone acetyltransferase; in vitro activity; in vivo; insight; member; mutant; programs; promoter; protein complex; response; yeast protein

DESCRIPTION (provided by applicant): The long-term objectives of the proposed project are to elucidate the mechanism of action and in vivo function of Mot1, an essential, conserved, transcriptional regulator in the yeast Saccharomyces cerevisiae. Mot1 forms a unique complex with the TATA-binding protein (TBP) and regulates TBP's function and DMA binding activity on a genome-wide scale. Mot1 is a member of a large family of evolutionary conserved nuclear ATPases (the Snf2/Swi2 family) involved in virtually all aspects of DMA metabolism. Defects in human Snf2/Swi2-related protein complexes contribute to certain cancers, Cockayne's Syndrome, a-thalassemia, and the most common form of X-linked mental retardation. Despite the ubiquitous occurrence of proteins in this family, their molecular mechanisms of action are not understood in detail, nor is it understood what roles many of these proteins play in vivo. Mot1 's ATPase activity is required to activate or repress transcription of specific genes in vivo. Consistent with its role as a repressor, Mot1 can dissociate TATA-binding protein (TBP)-DNA complexes in an ATP-dependent reaction. We propose that Mot1 can also activate transcription by using this activity to displace stably-bound, transcriptionally inactive forms of TBP from promoters. Such TBP recycling is proposed to provide quality control for transcription complex assembly and to ensure an adequate pool of free TBP for dynamic control of promoter activity genome-wide. Mot1- mediated activation also involves poorly understood cooperation with the NC2 and SAGA complexes. Biochemical, molecular biological, and genetic approaches will be used to test the recycling model and to define how Mot1, NC2 and SAGA cooperate in transcriptional control. Biochemical approaches will be used to test a specific and generally applicable model for Motl's catalytic mechanism in which ATP hydrolysis drives the interconversion of the ATPase between two different conformational forms. The proposed analysis of Mot1 function will lead to a better understanding of transcription complex dynamics and will provide general insight into how Snf2/Swi2-related proteins couple ATP hydrolysis to the generation of mechanical force.

描述（由申请人提供）：拟议项目的长期目标是阐明 Mot1 的作用机制和体内功能，Mot1 是酿酒酵母中必需的、保守的转录调节因子。 Mot1 与 TATA 结合蛋白 (TBP) 形成独特的复合物，并在全基因组范围内调节 TBP 的功能和 DMA 结合活性。 Mot1 是进化保守的核 ATP 酶大家族（Snf2/Swi2 家族）的成员，几乎参与 DMA 代谢的所有方面。人类 Snf2/Swi2 相关蛋白复合物的缺陷会导致某些癌症、科凯恩综合症、α-地中海贫血和最常见的 X 连锁智力低下。尽管该家族中的蛋白质普遍存在，但它们的分子作用机制尚未被详细了解，也不了解这些蛋白质中的许多在体内发挥什么作用。 Mot1 的 ATP 酶活性是激活或抑制体内特定基因转录所必需的。与其作为阻遏蛋白的作用一致，Mot1 可以在 ATP 依赖性反应中解离 TATA 结合蛋白 (TBP)-DNA 复合物。我们认为 Mot1 还可以通过利用这种活性从启动子中取代稳定结合的、转录失活形式的 TBP 来激活转录。这种 TBP 回收旨在为转录复合物组装提供质量控制，并确保有足够的游离 TBP 库来动态控制全基因组启动子活性。 Mot1 介导的激活还涉及与 NC2 和 SAGA 复合体的合作知之甚少。生物化学、分子生物学和遗传学方法将用于测试回收模型并定义Mot1、NC2和SAGA如何在转录控制中合作。生化方法将用于测试 Motl 催化机制的特定且普遍适用的模型，其中 ATP 水解驱动 ATP 酶在两种不同构象形式之间的相互转化。对 Mot1 功能的拟议分析将有助于更好地理解转录复合物动力学，并将提供对 Snf2/Swi2 相关蛋白如何将 ATP 水解与机械力的产生耦合的一般见解。