Genetic and Molecular Definition of Histone Modifying Enzyme Functions

组蛋白修饰酶功能的遗传学和分子定义

• 批准号: 10364649
• 负责人: SHARON Y. R. DENT
• 金额: $ 40万
• 依托单位: UNIVERSITY OF TX MD ANDERSON CAN CTR
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-04-01 至 2024-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10364649
• 关键词: Address; Affect; Alleles; Biochemical; Biological; Bromodomain; Cell Nucleus; Cells; Cerebellar Ataxia; Cerebellum; Chromatin; Complex; Development; Disease; Embryo; Enzymes; Foundations; Funding; Gene Expression; Gene Expression Regulation; Genetic; Genetic Transcription; Genome; Genomics; Goals; Growth; Histones; Human; Knowledge; Link; LoxP-flanked allele; Malignant Neoplasms; Mammalian Cell; Molecular; Mutant Strains Mice; Mutate; Mutation; Nerve Degeneration; Neurodegenerative Disorders; Pathway interactions; Proteins; Research; Role; SAGA; Spinal; Tissues; Work; XCL1 gene; cell behavior; enzyme activity; flexibility; histone acetyltransferase; histone modification; human disease; insight; novel; novel therapeutics; programs; stem cells

Understanding how histone modifications are regulated is fundamentally important for understanding mechanisms of chromatin organization and gene regulation in both normal and disease states. The overall goal of our research is to address this challenging question, using genetic and molecular approaches to define which histone modifying enzymes, and by extension, which histone modifications, govern specific gene expression programs in particular biological contexts. Our work is focused largely on the Gcn5 histone acetyltransferase (HAT) and the USP22 histone deubiquitylase (DUB), which are both components of a large multiprotein assembly termed SAGA. Gcn5, USP22 and other SAGA components have been implicated in human maladies, including cancer and neurodegeneration, but the molecular mechanisms underlying such effects are not known. Over the past 20 years, we have created a novel toolkit of Gcn5 and USP22 mutant mice and cells, including null alleles, conditional (floxed) alleles, and point mutated alleles (in the Gcn5 HAT domain, the Gcn5 bromodomain, or the USP22 DUB domain) that affect the activity of these enzymes. Our studies of Gcn5 mutations revealed key insights to both transcriptional and non-transcriptional functions for this HAT during development, and most recently, they revealed important connections between Gcn5 and Myc functions both in normal stem cells and in cancer. Our USP22 mutant mice revealed that this DUB is also critical for embryo survival, but through different pathways than those affected by Gcn5 loss. Despite these advances, many significant gaps in knowledge still remain. We have only a partial view of which transcription programs require Gcn5 in mammalian cells. Moreover, Gcn5 is now known to be part of a second histone modifying complex called ATAC, but we do not know how Gcn5 is apportioned between these complexes or their relative roles in development or disease. We also have an incomplete understanding of the roles of USP22 and the SAGA DUB module in specific tissues such as the cerebellum, which is especially relevant since specific components of the SAGA DUB module are linked to a debilitating neurodegenerative disease, spinal cerebellar ataxia type 7 (SCA7). This MIRA will provide us stable and flexible funding to continue our genetic, biochemical, and molecular studies to address these critically important questions. In the longer term, definition of the normal functions of Gcn5 and USP22 will provide molecular foundations for development of new therapeutic options for diseases in which these factors are mis-regulated.

了解组蛋白修饰的调节是从根本上重要的 了解染色质组织和基因调节的机制 疾病状态。我们研究的总体目标是解决这个挑战的问题 遗传和分子方法来定义哪种组蛋白修饰酶，并延伸 哪些组蛋白修饰，控制特定的基因表达程序，特别是生物学 上下文。我们的工作主要集中在GCN5组蛋白乙酰转移酶（HAT）和 USP22组蛋白去泛素酶（DUB），它们都是大型多蛋白的成分 大会称为传奇。 GCN5，USP22和其他SAGA组件已与 人类疾病，包括癌症和神经退行性，但分子机制 基础这种效果尚不清楚。在过去的20年中，我们创建了一个新颖的工具包 GCN5和USP22突变小鼠和细胞，包括无效等位基因，有条件的（Floxed）等位基因和 点突变等位基因（在GCN5帽子域，GCN5溴化域或USP22 DUB中 影响这些酶活性的结构域。我们对GCN5突变的研究揭示了关键 在开发过程中，该帽子的转录和非转录功能的见解， 最近，他们揭示了GCN5和MYC功能之间的重要联系 正常干细胞和癌症。我们的USP22突变小鼠表明该配音也很关键 对于胚胎生存，但通过与受GCN5损失影响的途径不同。尽管 这些进步，知识上的许多重大差距仍然存在。我们只有部分观点 哪些转录程序需要哺乳动物细胞中的GCN5。而且，GCN5现在已知 成为第二个组蛋白修饰复合物的一部分，称为ATAC，但我们不知道GCN5是如何的 这些复合物或它们在发育或疾病中的相对作用之间分配。我们也是 对特定的USP22和SAGA配音的角色有不完全的了解 小脑等组织，这特别相关，因为 传奇配音模块与衰弱的神经退行性疾病，脊柱小脑有关 共济失调7（SCA7）。这个mira将为我们提供稳定且灵活的资金，以继续我们的遗传 生化和分子研究，以解决这些至关重要的问题。更长的时间 术语，GCN5和USP22正常功能的定义将为分子基础提供 开发这些因素被错误监管的疾病的新治疗选择。