Promoter Regulation in Response to Environmental Stress

描述(申请人提供)：真核基因的调控涉及数百种蛋白质。它们如何在组成基因组的数千个基因中协同工作尚不清楚。当细胞基因组被重新编程以响应信号事件(如环境压力)时，这种相互作用如何变化，人们知之甚少。这里提出的工作是一个项目的继续，该项目旨在广泛调查模式真核生物Saccharomcyes cerevisiae基因组中转录调控蛋白的位置，以及当基因组受到环境信号(如热激和其他压力)重新编程时，它们转移到哪里。热冲击为单元提供了快速而简单的编程事件。目前对该项目的研究已经揭示了对基因调控的新见解，证明了预启动复合体部分组装在无核小体启动子区域。然而，完全组装需要去除位于启动子上游的“-1”核小体。在正常和热休克条件下，用芯片在低分辨率下测定了~200个基因和染色质调节蛋白的基因组位置。目前正在对数据进行分析。将通过为CHIP-SEQ改装芯片库来实现高分辨率测绘。使用试剂来修剪芯片DNA，将在一组精选的因素上实现更高分辨率的映射。结合事件之间的关系将为转录复合体的组装和调控提供新的见解。 与公共健康相关：我们的细胞不断面临极端环境，包括温度、饥饿、辐射和有害化学物质。我们如何应对这种压力取决于我们的转录机制对基因的作用。因此，广泛了解我们的转录机制在面对各种压力时是如何工作的，对于对人类健康的生理学理解是至关重要的。

DESCRIPTION (provided by applicant): The regulation of eukaryotic genes involves many hundreds of proteins. How they work together at the many thousands of genes that comprise a genome is not known. Little is known about how this interplay changes as cellular genomes are reprogrammed in response to signaling events such as environmental stress. The work proposed here is a continuation of a project to broadly survey where transcriptional regulatory proteins are located throughout the genome of the model eukaryotic organism Saccharomcyes cerevisiae, and where they translocate to when the genome is reprogrammed by environmental signals, such as heat shock and other stresses. Heat shock provides a rapid and simple programming event for the cell. Current studies on this project have already revealed novel insights into gene regulation by demonstrating that pre-initiation complexes partially assemble in nucleosome-free promoter regions. However, full assembly requires removal of the "-1" nucleosome located on the upstream side of the promoter. The genomic location of ~200 gene- and chromatin-regulatory proteins have been determined at low resolution by ChIP-chip, under normal and heat shock conditions. The data is now being analyzed. High resolution mapping will be achieved by retrofitting the ChIP-chip libraries for ChIP-seq. Even higher resolution mapping will be achieved on a select set of factors using reagents to trim the ChIP DNA. Relationships among binding events will provide new insights into transcription complex assembly and regulation. PUBLIC HEALTH RELEVANCE: Our cells are constantly faced with environmental extremes, involving temperature, starvation, radiation and harmful chemicals. How we deal with this stress depends upon the action of our transcription machinery on genes. Therefore a broad understanding of how our transcription machinery works in the face of various stresses is essential for a physiological understanding of human health.