Structural basis of replisome mediated DNA replication and repair

复制体介导的 DNA 复制和修复的结构基础

基本信息

批准号：
10620204
负责人：
Yang Gao
金额：
$ 38.43万
依托单位：
RICE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-08-01 至 2026-05-31
项目状态：
未结题

项目摘要

DNA is the blueprint of life and DNA replication and maintenance are essential for human health. Damages on DNA due to endogenous or environmental assaults can hamper DNA replication and induce genome abnormities and human diseases. A replisome is a multi-protein complex responsible for DNA replication. Moreover, as the first one to meet any replication barrier, the replisome plays essential roles in signaling replication stress and facilitating DNA repair. However, the structural basis of replisome operation and replisome mediated replication stress response and repair remains unclear. We propose to use biochemical reconstitution and cryo-EM structural determination to investigate how the replisome acts under normal and stressed conditions and how disfunction of the replisome leads to genetic variations and human diseases. First, we will employ replisome from bacteriophage T7 as a model system to investigate the structural basis of replisome operation under stressed conditions. I have recently obtained the first structure of the T7 replisome operating on its DNA substrate, which illustrated the organization and the working mechanism of a replisome. We will further investigate how the T7 replisome responses to various replication barriers to trigger appropriate replication-coupled repair. Second, we will investigate the structural basis of mitochondria DNA replication. Mitochondria is the power house of a cell and errors on mitochondria DNA due to faulty DNA replication are connected to many human genetic diseases. We will reconstitute the mitochondria replisome and investigate how mitochondria DNA is replicated and how mutations on mitochondria replisome lead to human diseases. Our investigations will provide the first structural framework for understanding replisome mediated DNA replication, stress response and repair. The structural information will contribute to the development of novel therapies to target or avoid targeting DNA replication.

DNA是生命的蓝图，DNA的复制和维护对于人类健康至关重要。由于内源性或环境攻击而造成的 DNA 损伤可能会阻碍 DNA 复制，诱发基因组异常和人类疾病。复制体是一种多蛋白复合物，负责用于DNA复制。此外，作为第一个遇到复制障碍的复制体，在发出复制应激信号和促进 DNA 修复方面发挥着重要作用。然而，结构基础复制体操作和复制体介导的复制应激反应和修复的机制仍不清楚。我们建议使用生化重建和冷冻电镜结构测定来研究如何复制体在正常和应激条件下发挥作用，以及复制体的功能障碍如何导致遗传变异和人类疾病。首先，我们将使用来自噬菌体 T7 的复制体作为模型系统研究应激条件下复制体操作的结构基础。我最近获得了第一个在其 DNA 底物上运行的 T7 复制体结构，说明了复制体的组织和工作机制。我们将进一步研究如何 T7 复制体对各种复制障碍做出反应，以触发适当的复制耦合维修。其次，我们将研究线粒体 DNA 复制的结构基础。线粒体线粒体 DNA 是细胞的动力室，由于 DNA 复制错误而导致的错误是与许多人类遗传疾病有关。我们将重建线粒体复制体并研究线粒体 DNA 的复制方式以及线粒体复制体的突变如何导致人类疾病。我们的调查将为理解提供第一个结构框架复制体介导DNA复制、应激反应和修复。结构信息将有助于开发靶向或避免靶向 DNA 复制的新疗法。