Histone Modifying Enzymes and Transcription

描述（由申请人提供）：本研究的长期目标是了解组蛋白修饰（如乙酰化和甲基化）的作用及其对染色体功能的影响，使用广泛研究的酵母酿酒酵母研究这些过程。特别是，该基金将重点关注组蛋白修饰对转录的影响。赠款有三个目标。第一个（1）集中于细胞周期蛋白依赖性激酶Bur 1如何控制组蛋白甲基化酶Set 2对组蛋白H3赖氨酸36的甲基化。已知Set 2在转录延伸过程中与RNA聚合酶II相关，我们认为Bur 1通过Set 2控制延伸过程中的关键步骤。第二个目标是使用质谱法对高度纯化的酵母组蛋白H2 A和H2 B进行鉴定，如赖氨酸残基的乙酰化和甲基化。一旦确定了特定的修饰残基，将研究它们突变的影响，并确定负责修饰的酶。第三个目标是研究Spt 10，这是一种已知对组蛋白基因和其他基因的转录很重要的蛋白质。根据其序列，Spt 10被认为是一种N-乙酰转移酶，但其底物可能不是组蛋白。一种涉及肽库的新方法将用于鉴定Spt 10乙酰化的蛋白质。由于组蛋白及其修饰从酵母到人类都是高度保守的，基因表达过程也是如此，这些研究将有助于更好地了解人类细胞中染色体的基本功能。

DESCRIPTION (provided by applicant): The long term goal of this research is to understand the role of histone modifications such as acetylation and methylation and their effect on chromosome function, using the widely-studied yeast, Saccharomyces cerevisiae, to study these processes. In particular this grant will focus on the effect of histone modifications on transcription. The grant has 3 aims. The first one (1) focuses on how the cyclin-dependent kinase Bur1 controls methylation of histone H3 lysine 36 by the histone methylase Set2. Set2 is known to be associated with RNA polymerase II during transcriptional elongation, and we think that Bur1 controls a crucial step in the elongation process, acting through Set2. The second aim is concerned with using mass spectroscopy on highly purified yeast histones H2A and H2B to identify modifications such as acetylation and methylation of lysine residues. Once specific modified residues have been identified, the effects of mutating them will be investigated and the enzymes responsible for the modifications will be determined. The third aim is to study Spt10, a protein known to be important for transcription of histone genes and perhaps other genes. Spt10 is thought to be an N-acetyltransferase based on its sequence, but its substrate may not be histones. A novel method involving peptide libraries will be used to identify the protein(s) that Spt10 acetylates. Since histones and their modifications are highly conserved from yeast to humans, as is the process of gene expression, these studies will lead to a greater understanding of fundamental functions of chromosomes in human cells.