Role of RPA Hyperphosphorylation in DNA Damage Responses

RPA 过度磷酸化在 DNA 损伤反应中的作用

• 批准号: 7885488
• 负责人: Moises Alejandro Serrano
• 金额: $ 3.06万
• 依托单位: EAST TENNESSEE STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-07-01 至 2013-12-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7885488
• 关键词: Address; Binding; Binding Proteins; Biochemical; Biological; Cell Cycle Progression; Cells; Chemicals; Coupling; DNA; DNA Damage; DNA Repair; DNA Repair Pathway; DNA damage checkpoint; DNA lesion; Data; Disease; Double Strand Break Repair; Down-Regulation; Environmental Hazards; Eukaryota; Excision; Exposure to; Failure; Goals; Health; Human; Laboratories; Malignant Neoplasms; Mediating; Metabolic Pathway; Molecular; Mutagenesis; Mutagens; Mutation; Nerve Degeneration; Pathway interactions; Phosphotransferases; Play; Premature aging syndrome; Proteins; Regulation; Replication Initiation; Replication Origin; Role; SS DNA BP; Signal Transduction; Single-Stranded DNA; Source; System; Testing; Time; Work; base; homologous recombination; human disease; insight; origin recognition complex; prevent; repaired; replication factor A; response; success; ultraviolet irradiation

DESCRIPTION (provided by applicant): Environmental hazards, including UV irradiation and genotoxic chemicals, are some of the major sources for DNA damage and believed to be the major cause to human cancers and also a cause to many other diseases such as premature aging and neurodegeneration. DNA repair and DNA damage checkpoints are the two major biological defense systems against DNA damage in cells. Coordination between these two machineries is crucial for timely removal of DNA damage, preventing the conversion of DNA lesions to permanent mutations due to replication infidelity. However, the molecular details of the coordination remain largely unknown. As the major single-stranded DNA (ssDNA) binding protein in eukaryotes, replication protein A (RPA) is involved in almost all DNA metabolic pathways such as replication, recombination, DNA damage checkpoints, and all types of DNA repair pathways. Despite its critical activity in all these pathways the question of whether and how RPA plays a role in the precise coordination between DNA repair and checkpoints remain to be elucidated. Recent findings from our laboratory have shown that RPA undergoes hyperphosphorylatlon in response to DNA damage. In this project we will test the hypothesis that the hyperphosphorylatlon may alter the biochemical activity of RPA for interaction with ssDNA and proteins, and thus may constitute an important regulatory mechanism by which some DNA damage response interactions are inhibited while others are activated owing to the failure or success of the molecular interactions with RPA. To test these hypotheses, we will specifically determine: 1) the role of hyperphosphorylated RPA in the suppression of origin firing; 2) the interaction between Rad51/Rad52 and RPA and its effect by RPA hyperphosphorylatlon; and 3) the cellular molecular interactions stimulated and/or disrupted by the hyperphosphorylation of RPA. The long-term goal of this project is to elucidate the molecular mechanism of DNA damage responses in human cells, and to better understand the damage-induced mutagenesis and related human diseases.

描述（由申请人提供）：环境危害，包括紫外线照射和遗传毒性化学品，是DNA损伤的一些主要来源，被认为是人类癌症的主要原因，也是许多其他疾病的原因，如过早衰老和神经变性。DNA修复和DNA损伤检查点是细胞内针对DNA损伤的两大生物防御系统。这两种机制之间的协调对于及时去除DNA损伤至关重要，防止DNA损伤因复制不忠而转化为永久性突变。然而，分子的协调细节仍然在很大程度上未知。作为真核生物中主要的单链DNA结合蛋白，复制蛋白A（RPA）参与了几乎所有的DNA代谢途径，如复制、重组、DNA损伤检查点以及所有类型的DNA修复途径。尽管RPA在所有这些途径中具有关键活性，但RPA是否以及如何在DNA修复和检查点之间的精确协调中发挥作用的问题仍有待阐明。我们实验室最近的研究结果表明，RPA在DNA损伤时会发生过度磷酸化。在本项目中，我们将检验这样的假设：超磷酸化可能会改变RPA与ssDNA和蛋白质相互作用的生化活性，从而可能构成一种重要的调节机制，通过这种机制，一些DNA损伤反应相互作用被抑制，而另一些DNA损伤反应相互作用则被激活。与RPA的分子相互作用的失败或成功。为了验证这些假设，我们将具体确定：1）过度磷酸化RPA在抑制起源放电中的作用; 2）Rad 51/Rad 52和RPA之间的相互作用及其通过RPA过度磷酸化的影响; 3）RPA过度磷酸化刺激和/或破坏的细胞分子相互作用。该项目的长期目标是阐明人类细胞DNA损伤反应的分子机制，并更好地了解损伤诱导的突变和相关的人类疾病。