Coordination of the late steps of human nucleotide excision repair

人类核苷酸切除修复后期步骤的协调

• 批准号: 7500156
• 负责人: Orlando D. Scharer
• 金额: $ 27.35万
• 依托单位: STATE UNIVERSITY NEW YORK STONY BROOK
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-09-24 至 2011-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7500156
• 关键词: Antineoplastic Agents; Binding; Biochemical; Biochemical Pathway; Biological; Biological Assay; Cell Nucleus; Cells; Chemicals; Complex; Condition; DNA; DNA Binding; DNA Binding Domain; DNA Damage; DNA Repair; DNA Repair Pathway; DNA Sequence; DNA lesion; Defect; ERCC1 gene; ERCC5 gene; Ensure; Etiology; Event; Excision; Genes; Genome Stability; Human; In Vitro; Inborn Genetic Diseases; Incidence; Individual; Inherited; Interdisciplinary Study; Investigation; Lesion; Life; Light; Malignant Neoplasms; Mediating; Molecular; Mutation; Nucleotide Excision Repair; Nucleotide Excision Repair Inhibition; Nucleotides; Oligonucleotides; Pathway interactions; Peptides; Pharmaceutical Preparations; Process; Proteins; Reaction; Recruitment Activity; Regulation; Repair Complex; Research; Resistance; Risk; Role; Single-Stranded DNA; Site; Site-Directed Mutagenesis; Skin Cancer; Substrate Specificity; Sunlight; Surface; Surgical incisions; Testing; Therapeutic Intervention; XPA gene; XPGC protein; Xeroderma Pigmentosum; adduct; antitumor agent; base; endonuclease; environmental agent; environmental mutagens; human disease; in vivo; insight; mutant; neoplastic cell; nuclease; protein function; protein protein interaction; repaired; tumor; ultraviolet damage; ultraviolet irradiation

DESCRIPTION (provided by applicant): Nucleotide Excision Repair (NER) is a versatile DNA repair pathway involved in the removal of diverse lesions, including those formed by UV light, from DNA. The importance of NER is underscored by the fact that the cancer-prone inherited disorder xeroderma pigmentosum is caused by defects in various NER genes. NER acts by the concerted action of over 30 proteins that sequentially assemble at sites of UV damage. Although the basic biochemical transactions involved in NER have been discerned, it is less well understood how the individual steps are coordinated to ensure smooth progression through the pathway. The research outlined here combines biochemical, cell biological, chemical and structural approaches to study the regulation and coordination of the dual incision and repair synthesis steps in NER. The proposal is guided by the hypothesis that the incisions, 5' to the lesion by ERCC1-XPF and 3' to the lesion by XPG, are temporarily and spatially regulated to avoid the formation of deleterious breaks and gaps in the process. We will test the specific hypothesis that this coordination is achieved by protein-protein interactions, DNA binding and catalytic activities as follows: 1) New structural information will be used to reassign and characterize the XPA-ERCC1 interaction domains and we will study how XPA recruits ERCC1-XPF to sites of NER. 2) We will study how individual DNA binding domains of ERCC1-XPF contribute to its catalytic activity and progression through the NER pathway. 3) We will investigate how the order of incisions by ERCC1-XPF and XPG and the coordination of incision and repair synthesis activities avoids the formation of single-stranded DNA gaps following excision of a 30 nucleotide long oligonuelcotide containing the damage. Our studies will provide new insight into the molecular basis of the regulation of a complex biochemical pathway in human cells as well as the molecular basis of inherited disease and the etiology of cancer. Since NER proteins also counteract the action of many clinically important antitumor agents, our studies will also contribute new targets for therapeutic intervention. Project Narrative: Nucleotide excision repair (NER) is a complex DNA repair pathway that counteracts damage to DNA caused by UV light, environmental agents and cancer chemotherapeutic drugs. Defects in NER genes result in the cancer-prone inherited disorder xeroderma pigmentosum and our interdisciplinary studies of this pathway contribute to our understanding of the molecular basis of human disease. Since NER proteins also contribute to the resistance of tumor cells to anti-cancer agents our investigations may also provide new targets for anti- tumor therapy.

描述（由申请人提供）：核苷酸切除修复（NER）是一种多功能的DNA修复途径，涉及从DNA中去除各种损伤，包括由UV光形成的损伤。NER的重要性是由以下事实强调的，即癌症倾向的遗传性疾病着色性干皮病是由各种NER基因的缺陷引起的。NER通过30多种蛋白质的协同作用发挥作用，这些蛋白质在紫外线损伤部位依次组装。虽然NER中涉及的基本生物化学交易已经被发现，但如何协调各个步骤以确保通过该途径的顺利进展还不太清楚。本文概述的研究结合了生物化学，细胞生物学，化学和结构方法来研究NER中双切口和修复合成步骤的调节和协调。该建议是由以下假设指导的：ERCC 1-XPF在损伤的5'端和XPG在损伤的3'端的切口被暂时和空间地调节，以避免在该过程中形成有害的断裂和间隙。我们将测试特定的假设，这种协调是通过蛋白质-蛋白质相互作用，DNA结合和催化活性实现如下：1）新的结构信息将用于重新分配和表征XPA-ERCC 1相互作用结构域，我们将研究XPA如何招募ERCC 1-XPF到NER的网站。2)我们将研究ERCC 1-XPF的单个DNA结合结构域如何通过NER途径促进其催化活性和进展。3)我们将研究ERCC 1-XPF和XPG的切口顺序以及切口和修复合成活性的协调如何避免在切除含有损伤的30个核苷酸长的寡核苷酸后形成单链DNA缺口。我们的研究将为人类细胞中复杂生化途径调节的分子基础以及遗传性疾病和癌症病因的分子基础提供新的见解。由于NER蛋白也抵消了许多临床上重要的抗肿瘤药物的作用，我们的研究也将为治疗干预提供新的靶点。 项目叙述：核苷酸切除修复（NER）是一种复杂的DNA修复途径，可以抵消紫外线、环境因子和癌症化疗药物对DNA的损伤。NER基因的缺陷导致易患癌症的遗传性疾病着色性干皮病，我们对这一途径的跨学科研究有助于我们了解人类疾病的分子基础。由于NER蛋白也有助于肿瘤细胞对抗癌药物的抗性，我们的研究也可能为抗肿瘤治疗提供新的靶点。