UNDERSTANDING THE MOLECULAR BASIS OF EPIGENETIC TRANSCRIPTIONAL SILENCING

了解表观遗传转录沉默的分子基础

• 批准号: 8360578
• 负责人: Yvonne Nsokika Fondufe-Mittendorf
• 金额: $ 18.38万
• 依托单位: UNIVERSITY OF KENTUCKY
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-07-01 至 2012-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8360578
• 关键词: Alpha Cell; Binding; Cells; Centers of Research Excellence; Chromatin; Complex; Data; Development; Epigenetic Process; Equilibrium; Event; Freezing; Funding; Gene Expression Regulation; Gene Silencing; Genes; Grant; Growth; Histones; Homeostasis; Malignant Neoplasms; Measures; Molecular; National Center for Research Resources; Partner in relationship; Pattern; Polymerase Chain Reaction; Principal Investigator; Regulator Genes; Relative (related person); Research; Research Infrastructure; Resources; Source; Structure; System; Testing; Time; Transcription Factor TFIIB; United States National Institutes of Health; Yeasts; base; chromatin immunoprecipitation; cost; gene repression; human disease; promoter; transcription factor

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Epigenetic silencing, the heritable repression of transcription within chromatin domains, is critical in eukaryotic gene regulation. Maintaining homeostasis requires a delicate balance of gene regulatory events involving transcription factors. Deregulation of silencing patterns ushers growth of aberrant cells, and development and proliferation of cancer. However, the molecular mechanism of epigenetic silencing remains unknown. My previous data indicate that silencing is initiated downstream of activator binding but upstream of TFIIB recruitment and preinitiation-complex assembly suggesting silencing acts through posttranslationally modifying histones, to govern TFIIB recruitment to promoters. This project aims to identify transcription factors and molecular mechanisms responsible for transcriptional silencing. We will determine the essential regulators of silenced genes by backtracking from TFIIB binding to activator binding and quantify the relative occupancy of these crucial regulators at silenced versus active genes. Utilizing the silenced mating system in yeast to examine the mechanism of silencing in a natural context, the extent of occupancy of key regulatory factors at the silenced/active mating loci in "a" and "alpha" cells, will be measured by chromatin immunoprecipitation and real-time polymerase chain reaction. We will test the hypothesis that these key regulators control silencing through ongoing, reversible, dynamic competition rather than through frozen, inert structure.

这个子项目是许多利用资源的研究子项目之一 由NIH/NCRR资助的中心拨款提供。子项目的主要支持 而子项目的主要调查员可能是由其他来源提供的， 包括其它NIH来源。 列出的子项目总成本可能 代表子项目使用的中心基础设施的估计数量， 而不是由NCRR赠款提供给子项目或子项目工作人员的直接资金。 表观遗传沉默是一种可遗传的染色质结构域内的转录抑制，在真核生物基因调控中起着重要作用。维持体内平衡需要涉及转录因子的基因调控事件的微妙平衡。沉默模式的失调导致异常细胞的生长以及癌症的发展和增殖。然而，表观遗传沉默的分子机制仍然未知。我以前的数据表明，沉默启动下游的激活剂结合，但上游的TFIIB招聘和preinitiation-complex组装表明沉默的行为，通过posterallymodifying组蛋白，管理TFIIB招聘启动子。 该项目旨在鉴定转录因子和负责转录沉默的分子机制。我们将通过从TFIIB结合到激活剂结合的回溯来确定沉默基因的基本调节剂，并量化这些关键调节剂在沉默基因与活性基因处的相对占有率。利用酵母中沉默的交配系统来检查自然环境中沉默的机制，将通过染色质免疫沉淀和实时聚合酶链反应来测量“a”和“α”细胞中沉默/活性交配位点处的关键调节因子的占据程度。我们将测试的假设，这些关键调节器控制沉默通过持续的，可逆的，动态的竞争，而不是通过冻结，惰性结构。