Promoter Regulation in Response to Environmental Stress

描述（由申请人提供）：真核生物将数百种（在某些情况下数千种）蛋白质用于基因表达的调节。然而，对于所有这些蛋白质如何在组成典型基因组的数千个基因上协调它们的行为，我们知之甚少。当细胞对包括环境压力在内的信号事件进行基因组重编程时，这种协调是如何改变的，我们知之甚少。本研究以酿酒酵母为模型细胞系统，广泛研究转录调节蛋白在基因组中的位置，以及当基因组受到环境信号（如热休克和其他应激）重编程时，转录调节蛋白迁移到何处。热休克为细胞提供了一个快速而简单的编程事件。该项目的初步研究已经通过证明许多基因在启动子处经历转录机制的部分组装，揭示了对基因调控的新见解。部分复合体等待信号事件使它们完全组装。染色质免疫沉淀法可以评估转录过程中涉及的多种蛋白质的位置，其中微阵列用于检测全基因组结合事件（即所谓的chlp芯片）。地点将在正常生长条件和广泛的环境压力下进行评估，特别强调热冲击。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。通过从细胞中分离的天然转录复合物的全基因组生化解剖，将提供额外的机制见解。我们的细胞经常面临极端环境，包括温度、饥饿、辐射和有害化学物质。我们如何处理这种压力取决于我们的转录机制的作用。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，对于从生理上理解人类健康是必不可少的。

DESCRIPTION (provided by applicant): Eukaryotes dedicate hundreds (and in some cases thousands) of proteins towards the regulation of gene expression. Yet very little is known about how all of these proteins coordinate their behavior at the many thousands of genes that comprise a typical genome. Little is known about how this coordination changes as cells reprogram their genome in response to signaling events including environmental stress. The work proposed here uses Saccharomyces cerevisiae as a model cellular system to undertake a broad survey of where transcriptional regulatory proteins are located throughout the genome, and where they move 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. Preliminary studies on this project have already revealed novel insights into gene regulation by demonstrating that many genes undergo partial assembly of the transcription machinery at promoters. Partial complexes await signaling events that drive them into full assembly. The location of a wide range of proteins involved in transcription will be evaluated by chromatin immunoprecipitation assays in which microarrays are used to detected genome-wide binding events (so called chlP-chip). Location will be assessed under normal growth conditions and under a wide range of environmental stresses, with particular emphasis on heat shock. Relationships among binding events will provide new insights into transcription complex assembly and regulation. Additional mechanistic insight will be provided through genome-wide biochemical dissection of native transcription complexes isolated from cells. 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. 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.