MECHANISMS OF TRANSCRIPTIONAL REGULATION IN CHROMATIN

染色质转录调控机制

• 批准号: 2185274
• 负责人: JERRY L WORKMAN
• 金额: $ 23.49万
• 依托单位: PENNSYLVANIA STATE UNIVERSITY, THE
• 依托单位国家: 美国
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-08-01 至 1997-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2185274
• 关键词: DNA binding protein; Xenopus; alternatives to animals in research; cell growth regulation; chromatin; fresh water environment; gene expression; gene induction /repression; genetic promoter element; histones; nucleosomes; transcription factor

The growth, differentiation and transformation of human cells is largely governed by the of cellular gene expression. One of the primary levels at which this regulation is applied is at the level of transcription. The importance of transcription control to cellular growth is evidenced by the observation that numerous nuclear oncogene products are regulatory transcription factors. In addition to the function of these and other regulatory transcription factors, structural, biochemical and genetic studies have indicated that chromosomal structural proteins also play a crucial role in the regulation of transcription. These proteins appear to prevent the interaction of RNA polymerases and basal factors with promoters of genes in cells where those genes are necessarily repressed. The long term goal of this application is to elucidate mechanisms by which this repression occurs and how regulatory transcription factors overcome this repression to activate specific genes in a programmed pattern of gene expression. Understanding the interactions of regulatory transcription factors with chromosomal structural proteins is a necessary step in elucidating the details of transcription control. This proposal is to perform a series of detailed biochemical studies on the interaction of different transcription factors with nucleosomes (the primary level of chromosome structure). Direct binding studies will be performed with purified factors and nucleosome core particles reconstituted with purified histones. These studies will reveal the ability of factors with different binding domains to interact with nucleosome DNA. Protein analysis of the purified bound complexes will reveal if the binding of some transcription factors leads to displacement of histones. In addition these studies will reveal if factors cooperate in binding to nucleosomes and the role of different factors in such processes. These results may indicate whether facilitated binding of to nucleosomes is a mechanism by which the combined action of multiple factors regulates transcription. Further studies will address the functional consequence of factors binding to nucleosomes in the activation of transcription. The function of acidic, glurich and pro-rich activation domains in overcoming nucleosome-mediated repression of transcription will be addressed (in fusion proteins with GAL4 and native factors). The role of histone modifications (i.e. acetylation) will be addressed in similar factor binding and transcription studies to investigate their role in transcription control.

人类细胞的生长，分化和转化在很大程度上是 受细胞基因表达的控制。 主要级别之一 应用该调节的是转录水平。 这 转录控制对细胞生长的重要性由 观察到众多核癌基产品是调节性的 转录因子。 除了这些和其他的功能 调节转录因子，结构，生化和遗传 研究表明，染色体结构蛋白也发挥 在转录调节中的关键作用。 这些蛋白质似乎 防止RNA聚合酶和基础因子与启动子的相互作用 这些基因一定会抑制的细胞中的基因。 长 该应用程序的术语目标是阐明此应用的机制 发生抑制以及调节转录因素如何克服这一点 抑制以编程基因模式激活特定基因 表达。 了解调节转录的相互作用 染色体结构蛋白的因素是必要的一步 阐明转录控制的细节。 该建议是 进行一系列有关相互作用的详细生化研究 核小体的不同转录因子（主要水平 染色体结构）。 直接结合研究将与 纯化的因子和核小体核心颗粒与纯化 组蛋白。 这些研究将揭示因不同的因素的能力 结合结构域与核小体DNA相互作用。 蛋白质分析 纯化的结合复合物将揭示某些转录的结合 因素导致组蛋白的位移。 另外，这些研究将 揭示因素在与核小体结合时是否合作和 在这样的过程中的不同因素。 这些结果可能表明是否 促进与核小体的结合是一种结合的机制 多种因素的作用调节转录。 进一步的研究将会 解决因素与核小体结合的功能结果 转录的激活。 酸性，格鲁希和富含酸性的功能 克服核小体介导的抑制的活化域 转录将被解决（在与GAL4和天然的融合蛋白中 因素）。 组蛋白修饰（即乙酰化）的作用将是 在类似因素结合和转录研究中解决 研究它们在转录控制中的作用。