High Resolution Mapping of Functional Elements in the Yeast Genome

芽殖酵母酿酒酵母被用作模型系统，以了解基因组机制， 哪种染色质组织得以建立。基因或启动子的起始位点通常被包裹在一个 无核小体区域，其以两个定位良好的核小体终止。这种精确的组织是 大多数基因的标准，并发挥这些基因是如何调节的。一个基本的 理解基因调控机制需要完全理解这种典型的 核小体组织出现并指导转录机器的放置。拟议工作 将利用典型核小体组织方面的生化重建， 基因组规模这将允许染色质组织因子和它们的 要明确定义的效应器。特别是，ATP依赖的染色质重塑复合物如何识别 DNA特征和序列特异性组织因素，将得到解决。染色质的组织 指导转录机器的有组织的组装。生化重组将被用来戏弄 除了染色质组织和激活子/阻遏子结合的选择性个体贡献外， 在基因组规模上组装转录机器。染色质通常被认为是由 核小体颗粒，含有四种核心组蛋白中的每一种的2个拷贝。然而，现在很明显 体内存在各种部分组装的核小体或亚核小体，这些结构可能起着 在染色质动力学中的重要作用。这些亚结构和组蛋白分子伴侣的存在， 可能参与其组装和拆卸的基因将在基因组规模上进行研究。

The budding yeast Saccharomyces cerevisiae is used as model system to understand genomic mechanisms by which chromatin organization is established. The start sites of genes, or promoters, are typically encased in a nucleosome-free region, that is bookended with two well-positioned nucleosomes. This precise organization is standard for most genes, and plays into how these genes are regulated. Therefore a fundamental understanding of gene regulatory mechanisms requires a complete understanding of how such canonical nucleosome organization arises and guides the placement of the transcription machinery. The proposed work will take advantage of biochemical reconstitution of aspects of canonical nucleosome organization on a genomic scale. This will allow individual mechanistic contributions of chromatin organizing factors and their effectors to be explicitly defined. In particular, how ATP-dependent chromatin remodeler complexes recognize DNA features and sequence-specific organizing factors, will be addressed. The organization of chromatin directs the organized assembly of the transcription machinery. Biochemical reconstitution will be used to tease apart selected individual contributions of chromatin organization and activator/repressor binding towards assembly of the transcription machinery on a genomic scale. Chromatin is generally thought to be composed of nucleosome particles containing 2 copies of each of the four core histones. However, it is now becoming clear that various partially assembled nucleosomes or subnucleosomes exist in vivo, and these structures may play critical roles in chromatin dynamics. The existence of these substructures and the histone chaperones that are likely to be involved in their assembly and disassembly will be investigated on a genomic scale.