DNA Replication Fidelity

工作总结：该项目的长期目标是通过多蛋白DNA复制和修复复合物了解DNA合成的保真度。今年，在三个领域取得了进展。我们确定了酵母DNA聚合酶的DNA合成的保真度，这是负责复制真核基因组的两种主要聚合酶之一。为了研究DNA聚合酶β在细胞中的作用，我们确定了DNA聚合酶β活性位点的点突变对其他复制蛋白存在各种缺陷的酵母菌株突变率的影响。我们还研究了酵母DNA聚合酶δ和γ-淀粉酶在胸腺嘧啶二聚体translesion合成过程中的聚合和纠错作用，胸腺嘧啶二聚体是一种暴露于阳光下的光产物，负责皮肤癌易感性的诱变。 背景资料：DNA聚合酶在细胞中并不单独工作，而是在相互关联的DNA加工途径中发挥作用，这些途径需要许多其他蛋白质来复制DNA并修复各种类型的环境DNA损伤。这些蛋白质中的一些决定DNA聚合酶可以复制哪些底物和/或影响DNA合成发生的效率和保真度。基于我们对纯化的DNA聚合酶的结构-功能研究，该项目的目标是了解多蛋白质DNA复制和DNA修复复合物对DNA合成的保真度，并了解干扰这些复合物如何导致与环境疾病相关的基因组不稳定性。这项工作的一个关键组成部分是在vi中连接

Summary of Work: The long-term goal of this project is to understand the fidelity of DNA synthesis by multiprotein DNA replication and repair complexes. This year, progress was made in three areas. We determined the fidelity of DNA synthesis by yeast DNA polymerase epsilon, one of the two major polymerases responsible for replicating the eukaryotic genome. To investigate the role of DNA polymerase epsilon in cells, we determined the influence of a point mutation in the active site of DNA polymerase epsilon on mutation rates in yeast strains with a variety of defects in other replication proteins. We also investigated the roles of yeast DNA polymerases delta and epsilon in polymerization and error correction during translesion synthesis past a thymine dimer, a photoproduct resulting from exposure to sunlight and responsible for the mutagenesis underlying susceptibility to skin cancer. Background: DNA polymerases do not work alone in cells, but function within interconnected DNA processing pathways that require many other proteins to replicate DNA and to repair various types of environmental DNA damage. Some of these proteins determine which substrates a DNA polymerase can copy and/or influence the efficiency and fidelity with which DNA synthesis occurs. Building on our structure-function studies of purified DNA polymerases, the goal of this project is to understand the fidelity of DNA synthesis by multi-protein DNA replication and DNA repair complexes, and to understand how perturbing these complexes may result in genome instability associated with environmental disease. A critical component of this effort is to connect in vi