GAGA FACTOR AND HEAT SHOCK PROMOTER POTENTIATION

GAGA 因子和热休克启动子增强作用

• 批准号: 6385053
• 负责人: ERIK D ANDRULIS
• 金额: $ 4.02万
• 依托单位: CORNELL UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-04-01 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/6385053
• 关键词: Drosophilidae; arthropod genetics; chromatin; fungal genetics; genetic promoter element; protein binding; protein protein interaction; protein structure function; stress proteins; transcription factor; yeast two hybrid system

The heat shock response of Drosophila melanogaster is characterized by the rapid and robust activation of the major heat shock genes. Although much is known about heat shock promoter architecture and the transcription factors which recognize the promoters, the mechanistic detail of heat shock gene transcription remain unclear. Two transcription factors, GAGA factor (GAF) and TATA-binding protein, and RNA polymerase II (Pol II) occupy the uninduced heat shock promoters. Pol II, although capable of producing small transcripts, is paused at the heat shock promoter. It is thought that the protein-protein and protein-DNA interactions among these factors play an important role in the maintenance of the open chromatin structure at the promoter and in retention of the paused polymerase. To address this hypothesis, DNA-binding domain and interaction domain mutants of GAF will be constructed and subjected to rigorous in vivo and in vitro analysis. Given the similarities between heat shock promoter sequences and those of other promoters, and the presence of a paused polymerase on several non-heat shock genes in Drosophila and in mammalian cells, studies with these GAF mutants may provide a general understanding of promoter architecture, polymerase pausing, and gene activation.

果蝇的热休克响应的特征是主要热休克基因的快速而强大的激活。 尽管对热激启动子结构和识别启动子的转录因子知之甚少，但热休克基因转录的机理细节尚不清楚。 两个转录因子，GAGA因子（GAF）和TATA结合蛋白，RNA聚合酶II（POL II）占据了未诱导的热激启动子。 pol II虽然能够产生小的转录本，但在热冲击启动子上停了下来。 人们认为，这些因素之间的蛋白质 - 蛋白质和蛋白-DNA相互作用在启动子的开放染色质结构和暂停聚合酶的保留方面起着重要作用。 为了解决这一假设，将构建GAF的DNA结合结构域和相互作用结构域突变体，并进行严格的体内和体外分析。 鉴于热激启动子序列与其他启动子的相似性，以及在果蝇和哺乳动物细胞中的几个非热休克基因上暂停聚合酶的存在，这些GAF突变体的研究可能会提供对启动子结构，聚合酶暂停和基因活化的一般理解。