MECHANISM OF SYNERGISTIC GENE ACTIVATION BY ZEBRA

斑马协同基因激活机制

基本信息

批准号：
6180510
负责人：
MICHAEL F CAREY
金额：
$ 27万
依托单位：
UNIVERSITY OF CALIFORNIA LOS ANGELES
依托单位国家：
美国
项目类别：
财政年份：
1998
资助国家：
美国
起止时间：
1998-07-01 至 2002-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/6180510
关键词：
DNA footprinting Epstein Barr virus RNase protection assay gene expression genetic promoter element genetic regulatory element genetic transcription nuclear runoff assay nucleoproteins transcription factor virus genetics

项目摘要

The long term objective of our work is to understand the molecular mechanisms underlying synergistic gene expression in eukaryotic cells. We will study how a well-characterized eukaryotic transactivator called ZEBRA differentially controls transcription of a family of target genes involved in the lytic cycle of Epstein-Barr virus. Our hypothesis is that the concentration of ZEBRA regulates the timing of target gene expression, and that different promoters respond to specific activator thresholds based on a promoter architecture that guides the cooperative assembly of upstream promoter-activator complexes and the ability of these complexes to recruit limiting components of the RNA polymerase II general transcription machinery to a gene. Our approach will be to correlate biochemical events in purified transcription systems with natural lytic expression patterns to establish a model for how a single activator can singularly control a genetic regulatory circuit. Our specific aims are to i.) refine our knowledge of ZEBRA-mediated differential gene regulation in vivo and recreate expression of a subset of target genes in vitro; ii) employ purified ZEBRA, Sp-1 and HMG-1 in a study of how promoter architecture regulates assembly of nucleoprotein structures called enhanceosomes on target promoters; iii) investigate the biochemical mechanism by which activators recruit TFIIA, TFIID and TFIIB to a core promoter to nucleate assembly of a preinitiation complex and iv.) further study the biochemical details of a ZEBRA-mediated isomerization event in TFIID, necessary for full levels of gene activation in vitro. The mechanism by which a eukaryotic activator controls gene expression has represented one of the most intensively studied problems in contemporary biology, largely because of the central role aberrant gene expression plays in pathological processes. My laboratory has the technology to combine biochemical and biologic approaches towards understanding the molecular details of this central issue.

我们工作的长期目标是了解分子真核细胞中协同基因表达的机制。我们将研究一种被充分表征的真核反式激活蛋白 ZEBRA 差异性地控制靶基因家族的转录参与 Epstein-Barr 病毒的裂解循环。我们的假设是 ZEBRA的浓度调节靶基因的时间表达，并且不同的启动子响应特定的激活剂基于指导合作社的发起人架构的阈值上游启动子-激活子复合物的组装和能力这些复合物招募 RNA 聚合酶 II 的限制性成分基因的一般转录机制。我们的方法将是将纯化转录系统中的生化事件与自然裂解表达模式建立了一个模型激活剂可以单独控制基因调节回路。我们的具体目标是 i.) 完善我们对 ZEBRA 介导的知识体内差异基因调控并重建子集的表达体外靶基因； ii) 在中使用纯化的ZEBRA、Sp-1和HMG-1 启动子结构如何调节核蛋白组装的研究目标启动子上称为增强体的结构； iii) 调查激活剂招募 TFIIA、TFIID 和的生化机制 TFIIB 与核心启动子一起使预引发复合物成核组装 iv.) 进一步研究 ZEBRA 介导的生化细节 TFIID 中的异构化事件是基因全水平所必需的体外激活。真核激活剂控制基因表达的机制代表了最深入研究的问题之一当代生物学，很大程度上是因为异常基因的核心作用表达在病理过程中发挥作用。我的实验室有结合生化和生物学方法的技术了解这个中心问题的分子细节。