Genetic Analysis of H2B Ubiquitylation in Yeast

酵母中 H2B 泛素化的遗传分析

• 批准号: 7904473
• 负责人: MARY ANN OSLEY
• 金额: $ 16.45万
• 依托单位: UNIVERSITY OF NEW MEXICO
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-08-31 至 2012-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7904473
• 关键词: Acute leukemia; Address; Affect; Aging; Biological; Cell model; Cells; Chromatin; Chromatin Structure; Code; Complex; Coupled; DNA Microarray Chip; DNA Polymerase II; Disease; Elongation Factor; Epigenetic Process; Gene Expression; Genes; Genetic Transcription; Glucose; Goals; Growth; Histone H2B; Histone H3; Histones; Human; Ligase; Link; Lysine; Malignant Neoplasms; Mediating; Methylation; Modification; Molecular; Molecular Chaperones; Molecular Genetics; Mutate; Mutation; Neurodegenerative Disorders; Nucleosomes; Nutrient; Pathway interactions; Peptide Hydrolases; Phase; Phenotype; Phosphorylation; Phosphotransferases; Protein Kinase; Proteins; Regulation; Regulatory Pathway; Reporting; Research; Role; SET Domain; Saccharomyces cerevisiae; Saccharomycetales; Serine; Signal Pathway; Signal Transduction; Testing; Transcriptional Activation; Ubiquitin; Yeasts; chromatin immunoprecipitation; deprivation; genetic analysis; genome-wide; histone methyltransferase; histone modification; in vivo; insight; mutant; neoplastic cell; novel; promoter; ubiquitin-protein ligase

DESCRIPTION (provided by applicant): Histone covalent modifications are tightly linked to the regulation of eukaryotic gene expression. Monoubiquitylation of histone H2B (H2Bub) in the budding yeast, Saccharomyces cerevisiae, is associated with transcriptional activation, and regulates a novel trans-histone pathway that leads to methylation of histone H3 on lysines 4 (H3K4) and 79 (H3K79). The broad goals of the proposed research are to understand how H2Bub is regulated and how this histone modification influences transcription and stationary phase, a specialized quiescent state that results from nutrient deprivation. These goals will be pursued in three specific aims. In Specific Aim 1, the role of H2Bub in Pol II transcription will be defined using genetic and molecular approaches to determine if the histone modification co-operates with histone chaperones to regulate chromatin stability during Pol II initiation and elongation. In Specific Aim 2, the factors that regulate H2Bub will be studied by focusing on the roles of the E3 ligase, Bre1, in activation of the E2, Rad6. In Specific Aim 3, molecular and genetic approaches will be employed to identify the factors that regulate the deubiquitylation of H2Bub when cells enter stationary phase and the rapid ubiquitylation of H2B when cells re-enter the growth phase. The role of H2Bub in stationary phase will be investigated using molecular and cell biological approaches to determine whether H2Bub regulates the formation of quiescent cells. Aberrations in transcription can frequently result from epigenetic changes that are linked to the modification state of histones. These changes, in turn, have been associated with a number of disease states. The proposed studies on H2B ubiquitylation have relevance to cancer through the role of H2Bub in the trans- histone methylation of H3K4. The human SET domain protein, MLL1, is an H3K4 histone methyltransferase that is frequently rearranged in acute leukemias, and thus studies in yeast could provide insight into the roles of aberrant H3K4 methylation in tumor cells. In addition, studies on the role of H2Bub in cellular quiescence could provide a new understanding of aging and neurodegenerative diseases.

描述（由申请人提供）：组蛋白共价修饰与真核基因表达的调控紧密相关。组蛋白H2B（H2Bub）在芽殖酵母（Saccharomycescerevisiae）中的单泛素化与转录激活相关，并且调节导致组蛋白H3在赖氨酸4（H3K4）和79（H3K79）上的甲基化的新的转组蛋白途径。拟议研究的广泛目标是了解H2Bub是如何调节的，以及这种组蛋白修饰如何影响转录和静止期，这是一种由营养缺乏引起的特殊静止状态。这些目标将在三个具体目标中实现。在特定目标1中，将使用遗传和分子方法来确定H2Bub在Pol II转录中的作用，以确定组蛋白修饰是否与组蛋白伴侣蛋白合作，以在Pol II起始和延伸期间调节染色质稳定性。在具体目标2中，将通过关注E3连接酶Bre1在E2 Rad6激活中的作用来研究调节H2Bub的因素。在具体目标3中，将采用分子和遗传方法来确定当细胞进入稳定期时调节H2Bub去泛素化的因子，以及当细胞重新进入生长期时调节H2B快速泛素化的因子。将使用分子和细胞生物学方法研究H2Bub在静止期的作用，以确定H2Bub是否调节静止细胞的形成。转录异常通常是由与组蛋白修饰状态相关的表观遗传变化引起的。这些变化反过来又与一些疾病状态有关。所提出的关于H2B泛素化的研究通过H2Bub在H3K4的反式组蛋白甲基化中的作用与癌症相关。人类SET结构域蛋白MLL1是一种H3K4组蛋白甲基转移酶，在急性白血病中经常重排，因此在酵母中的研究可以深入了解异常H3K4甲基化在肿瘤细胞中的作用。此外，对H2Bub在细胞静止中的作用的研究可以为衰老和神经退行性疾病提供新的认识。