Regulation of DNA Replication and Repair

DNA 复制和修复的调控

• 批准号: 6887404
• 负责人: MARK D. SUTTON
• 金额: $ 29.7万
• 依托单位: STATE UNIVERSITY OF NEW YORK AT BUFFALO
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-05-01 至 2008-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6887404
• 关键词: DNA damage; DNA directed DNA polymerase; DNA repair; DNA replication; DNA replication origin; Escherichia coli; cell cycle; enzyme mechanism; mutant; protein binding

DESCRIPTION (provided by applicant): The long-term goal of this research is to understand how organisms accurately duplicate their genetic material by coordinating the actions of their DNA replication machinery with those of other cellular proteins involved in repair, damage tolerance, and cell cycle progression. Failure of an organism to do so can have catastrophic consequences ranging from disease, such as cancer, to death. The proposed research program utilizes both biochemical and genetic approaches to understand the roles played by the beta processivity clamp of the E. coli replicative DNA polymerase in coordinating DNA replication, repair, damage tolerance, and cell cycle progression. The beta clamp participates in a DNA damage checkpoint control as well as in translesion DNA synthesis (TLS). In addition, it interacts with a variety of proteins known to function in various aspects of DNA metabolism. As one Aim, we will test our hypothesis that unique interactions of beta with the different umuDC gene products influence the choice between replication, checkpoint, and TLS. These studies will have broad relevance to understanding integration of replication and TLS in both prokaryotic and eukaryotic cells. As a second Aim, we will test our proposal that beta participates in at least one DNA repair and/or umuDC-independent damage tolerance function by determining the molecular basis of the UV light sensitivity of a dnaN59 beta mutant. These studies will further our understanding of mechanisms that couple replication and repair. As a third Aim, we will test our hypothesis that certain partner proteins bind to overlapping surfaces on beta, and that by competing with each other for binding to the clamp, beta is able to regulate which proteins gain access to the replication fork. These studies will provide important insights into fundamental mechanisms of polymerase switching and replication fork management. In summation, we anticipate that the study of the coordinated regulation of DNA replication, DNA damage tolerance and repair, and cell cycle progression in E. coli will provide a valuable framework for understanding these same processes in humans, where the complexity of the events is far greater.

描述（由申请人提供）：本研究的长期目标是了解生物体如何通过协调其DNA复制机制与参与修复、损伤耐受性和细胞周期进程的其他细胞蛋白质的作用来准确地复制其遗传物质。如果生物体不能做到这一点，可能会造成灾难性的后果，从疾病（如癌症）到死亡。拟议的研究计划利用生化和遗传方法来了解大肠杆菌复制DNA聚合酶的β加工钳在协调DNA复制、修复、损伤耐受性和细胞周期进程中所起的作用。β钳参与DNA损伤检查点控制以及翻译DNA合成（TLS）。此外，它还与多种已知在DNA代谢的各个方面起作用的蛋白质相互作用。作为一个目标，我们将验证我们的假设，即β与不同的umuDC基因产物的独特相互作用会影响复制、检查点和TLS之间的选择。这些研究将对理解原核和真核细胞中复制和TLS的整合具有广泛的相关性。作为第二个目标，我们将通过确定dnaN59 β突变体的紫外光敏感性的分子基础来验证我们的提议，即β参与至少一种DNA修复和/或不依赖于umudc的损伤耐受功能。这些研究将进一步加深我们对复制和修复耦合机制的理解。作为第三个目标，我们将验证我们的假设，即某些伴侣蛋白结合在β的重叠表面上，并且通过相互竞争以结合钳，β能够调节哪些蛋白质进入复制叉。这些研究将为聚合酶转换和复制叉管理的基本机制提供重要的见解。总之，我们预计对大肠杆菌中DNA复制、DNA损伤耐受和修复以及细胞周期进程的协调调节的研究将为理解人类中这些相同的过程提供一个有价值的框架，在人类中，这些过程的复杂性要大得多。