SWI/SNF chromatin remodeling in nucleotide excision repair

核苷酸切除修复中的 SWI/SNF 染色质重塑

• 批准号: 8658223
• 负责人: FENG GONG
• 金额: $ 1.26万
• 依托单位: UNIVERSITY OF MIAMI SCHOOL OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-08-10 至 2015-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8658223
• 关键词: Binding; Biochemical; Biochemistry; Biological Assay; Cells; Chromatin; Chromatin Remodeling Factor; Chromatin Structure; Complement; Complex; DNA; DNA Binding; DNA Damage; DNA Double Strand Break; DNA Repair; DNA Repair Pathway; DNA lesion; Defense Mechanisms; Detection; Development; Due Process; Environment; Environmental Exposure; Eukaryotic Cell; Genetic Transcription; Genome; Genome Stability; Goals; Guanine Nucleotide Exchange Factors; Health; Hereditary Disease; Histones; Human; Human Genetics; In Vitro; Knowledge; Label; Laboratories; Link; Mammalian Cell; Metabolism; Methods; Microscopy; Molecular; Monitor; Nucleosomes; Nucleotide Excision Repair; Organism; Pathway interactions; Play; Positioning Attribute; Prevention strategy; Process; Proteins; Recruitment Activity; Repair Complex; Research; Role; Saccharomyces cerevisiae; Site; System; Techniques; Testing; Ultraviolet Rays; Yeasts; cancer therapy; chromatin immunoprecipitation; chromatin modification; chromatin remodeling; cigarette smoking; disease-causing mutation; gene function; histone modification; innovation; protein protein interaction; prototype; public health relevance; reconstitution; repaired; research study; skin cancer prevention; ultraviolet; ultraviolet damage; ultraviolet irradiation; ultraviolet lesions; yeast genetics

DESCRIPTION (provided by applicant): A wide variety of human genetic diseases are caused by mutations in genes that function in DNA repair pathways. As an important defense mechanism to maintain genome stability, DNA repair also contributes to the normal development and health of organisms. Bulky DNA lesions resulting from ultraviolet (UV) radiation, cigarette smoke and other endogenous and exogenous agents are repaired by the conserved nucleotide excision repair (NER) pathway. The assembly of DNA into chromatin in eukaryotic cells interferes with the NER process. How NER operates in the context of chromatin is largely unknown. Our previous studies in Saccharomyces cerevisiae first linked the prototype ATP-dependent chromatin remodeling complex SWI/SNF to NER. Very recent findings from our group and others have established a connection between SWI/SNF and NER in human cells. However, the process by which SWI/SNF remodels chromatin to facilitate NER remains undefined. Also unknown is the SWI/SNF recruitment mechanism in NER facilitation. The central objective of this proposal is to elucidate the mechanism by which SWI/SNF facilitates damage detection and repair in S. cerevisiae and cultured mammalian cells. Additionally, in vitro biochemical studies will be undertaken to validate cellular findings and provide detailed biochemical mechanisms on the coordination of chromatin remodeling and NER. We hypothesize that DNA damage recognition factors recruit SWI/SNF to sites of DNA damage via protein-protein interactions. We will also test an alternative mechanism that histone modifications are involved in SWI/SNF recruitment/or retention at sites of UV damage. In Aim I, we will determine the role of chromatin modifying activities required for efficient global genome NER (GG-NER) in yeast. We will investigate SWI/SNF remodeling at the Sir complex coated HML locus during NER. Aim II will discern the role of chromatin modification and remodeling during NER in mammalian cells. We will investigate the consequence of SWI/SNF inactivation on the dynamic NER process. In Aim III, we will ascertain the mechanisms of damage recognition and NER of nucleosomes in vitro. A purified system will be used to examine how a DNA lesion 'buried' in a mononucleosome is detected by DDB2 and XPC and how SWI/SNF remodels the mononucleosome to facilitate damage detection.

描述（由申请人提供）：多种人类遗传性疾病是由DNA修复途径中的基因突变引起的。DNA修复作为维持基因组稳定的重要防御机制，也有助于生物体的正常发育和健康。由紫外线（UV）辐射、香烟烟雾和其他内源性和外源性试剂引起的大体积DNA损伤通过保守的核苷酸切除修复（NER）途径修复。在真核细胞中，DNA组装成染色质会干扰NER过程。NER如何在染色质的背景下运作在很大程度上是未知的。我们先前在酿酒酵母中的研究首先将原型ATP依赖的染色质重塑复合物SWI/SNF与NER联系起来。我们小组和其他人最近的发现已经建立了SWI/SNF和NER在人类细胞中的联系。然而，SWI/SNF重塑染色质以促进NER的过程仍然不确定。同样不为人知的是社会工作局/国家家庭基金在促进净入学率方面的招募机制。该建议的中心目标是阐明SWI/SNF促进S.酿酒酵母和培养的哺乳动物细胞。此外，将进行体外生化研究，以验证细胞结果，并提供有关染色质重塑和NER协调的详细生化机制。我们推测DNA损伤识别因子通过蛋白质-蛋白质相互作用将SWI/SNF募集到DNA损伤位点。我们还将测试另一种机制，即组蛋白修饰参与UV损伤位点的SWI/SNF募集/或保留。在目的I中，我们将确定在酵母中高效的全局基因组NER（GG-NER）所需的染色质修饰活动的作用。我们将研究NER过程中Sir复合物包被的HML位点的SWI/SNF重塑。目的二是了解哺乳动物细胞核内转录还原过程中染色质修饰和重构的作用。我们将研究SWI/SNF失活对动态NER过程的影响。第三部分，我们将在体外研究核小体的损伤识别机制和NER。纯化的系统将用于检查DDB 2和XPC如何检测“埋藏”在单核小体中的DNA损伤，以及SWI/SNF如何重塑单核小体以促进损伤检测。