Histone Eviction and Mediator Function in Transcriptional Activation in Yeast

酵母转录激活中的组蛋白驱逐和介体功能

• 批准号: 0949722
• 负责人: Randall Morse
• 金额: $ 55.62万
• 依托单位: Health Research Incorporated/New York State Department of Health
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-05-01 至 2015-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0949722&HistoricalAwards=false
• 关键词: Histone; Eviction; Mediator; Function; Transcriptional

Intellectual merit: The long term goal of this project is to gain new understanding into mechanisms of transcriptional control in eukaryotes. Regulation of gene transcription is central to growth, development, and response to environment in all cells; thus, understanding transcriptional control is a central goal in genetics. The specific goals of this project are to gain new insight into chromatin remodeling during gene activation, and into the role of the Mediator complex in gene regulation. DNA in higher organisms, including humans, is packaged into nucleosomes by wrapping around an octamer of histone proteins. This creates a potential impediment to protein-DNA interactions needed for transcription of DNA into RNA, and so at many genes these nucleosomes must be remodeled to allow transcription to occur. This project will focus on chromatin remodeling at the CHA1 gene in the yeast Saccharomyces cerevisiae. Genetic and biochemical approaches will be used to examine the mechanism by which remodeling leads to histone eviction at CHA1 and at additional inducible promoters. Studies will also be conducted to investigate the role of the Mediator complex in transcriptional regulation in yeast. Mediator is a large, multi-subunit complex, comprising tail, middle, and head modules that bridges activators, whose binding is the initial step in gene activation, and the general transcription machinery. Mediator is highly conserved across the eukaryotic kingdom, and serves as a conduit for many regulatory signals, but the mechanism by which it controls gene expression is not well understood. Research will be carried out to determine whether one specific part of the Mediator complex, called the tail module, has specific functions aside from its requirement for recruitment of the middle and head modules, and to determine the role of the tail module of Mediator in CHA1 activation, in genome-wide recruitment of Mediator, and in transcriptional repression. Overall, this project will provide new information on fundamental aspects of transcriptional activation which at present is poorly understood. Transcriptional mechanisms are well conserved across eukaryotes. Hence, the information gained from this work will be broadly applicable.Broader impactThis research will include training of a graduate student and postdoctoral fellow. In addition, undergraduates will be recruited to participate in this project as summer interns, to be funded by REU supplements. The project will also result in generation of large data sets from microarray studies, and these will be made publicly available, both by providing raw data files to a public repository (GEO), and by making more user-friendly, processed data files available for download from the principal investigator's web site.

智力优点：该项目的长期目标是对真核生物中转录控制机制有了新的了解。 基因转录的调节对于所有细胞的生长，发育和对环境的反应至关重要。因此，理解转录控制是遗传学的核心目标。该项目的具体目标是在基因激活过程中对染色质重塑的新见解，以及介质复合物在基因调节中的作用。包括人类在内的较高生物体中的DNA通过包裹组蛋白的八聚体来包装到核小体中。 这会产生对DNA转录到RNA所需的蛋白-DNA相互作用的潜在障碍，因此在许多基因上，必须重塑这些核小体以允许进行转录。 该项目将着重于酿酒酵母中CHA1基因的染色质重塑。 遗传和生化方法将用于检查重塑导致CHA1和其他诱导启动子的组蛋白驱逐的机制。还将进行研究以研究介质复合物在酵母中转录调节中的作用。 介体是一种大型的多支化合物复合物，包括桥接激活剂的尾部，中间和头部模块，其结合是基因激活的第一步和一般的转录机械。 介体在整个真核生物王国中是高度保守的，并且是许多调节信号的管道，但是它控制基因表达的机制尚不清楚。 将进行研究，以确定介体复合物的一个特定部分（称为尾部模块）是否具有招募中间和头部模块的需求，并确定介体模块在CHA1激活中的作用，在整个基因组的介体募集中的作用以及在转录抑制中的作用。 总体而言，该项目将提供有关转录激活的基本方面的新信息，目前对此知之甚少。 转录机制在整个真核生物中得到很好的保守。因此，从这项工作中获得的信息将广泛适用。BoaderImpact这项研究将包括对研究生和博士后研究员的培训。 此外，将招募本科生作为暑期实习生参加该项目，并由REU补充剂资助。该项目还将从微阵列研究中产生大型数据集，并且通过向公共存储库（GEO）提供原始数据文件，并通过使更具用户友好的，处理过的数据文件可从主要研究人员的网站下载。