Structural basis of replisome mediated DNA replication and repair

DNA是生命的蓝图，DNA的复制和维持对人类健康至关重要。 由于内源性或环境攻击对DNA的损伤可阻碍DNA复制， 导致基因组异常和人类疾病。复制体是一种多蛋白复合体， for DNA复制.此外，作为第一个遇到任何复制障碍的复制体， 在传递复制应激信号和促进DNA修复中发挥重要作用。然而，结构基础 复制体的运作和复制体介导的复制应激反应和修复机制尚不清楚。 我们建议使用生化重建和冷冻电镜结构测定，以调查如何 复制体在正常和应激条件下起作用，以及复制体的功能障碍如何导致 基因变异和人类疾病。首先，我们将使用来自噬菌体T7的复制体作为噬菌体的复制体。 模型系统，以研究应激条件下复制体操作的结构基础。我 最近获得了在其DNA底物上操作的T7复制体的第一个结构， 阐明了复制体的结构和工作机制。我们将进一步调查 T7复制体响应于各种复制障碍，以触发适当的复制偶联， 修复.其次，我们将研究线粒体DNA复制的结构基础。线粒体 线粒体是细胞的动力室，由于错误的DNA复制而导致的线粒体DNA错误， 与许多人类遗传疾病有关。我们将重组线粒体复制体， 研究线粒体DNA如何复制以及线粒体复制体上的突变如何导致 人类疾病。我们的研究将提供第一个结构框架， 复制体介导的DNA复制、应激反应和修复。结构信息将 有助于开发针对或避免针对DNA复制的新型疗法。

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.