Structural and Mechanistic Studies of DNA Damage Bypass Pathways in Eukaryotes

项目概要/摘要 DNA损伤是对基因组稳定性的严重威胁。这是因为它会干扰DNA 复制导致突变和染色体重排-癌症的标志， 衰老和其他疾病。为了确保基因组的稳定性，细胞利用DNA损伤旁路 在复制过程中科普DNA损伤的途径。我们研究的长期目标是 该计划旨在了解DNA损伤旁路是如何在真核系统中进行的， 结构和机制层面。我们的研究将集中在两个损害旁路途径： 跨损伤合成和模板转换。这一领域的进展最近有所放缓， 与研究各种旁路组件如何组装成 并在大的、动态的、多蛋白质复合体中发挥作用。我们开发了 生物化学、生物学、生物物理学、计算和结构工具， 这些挑战。这使我们处于一个独特的位置来回答许多基本问题 关于损害绕过。我们未来的研究计划分为三大项目。一是 将研究DNA损伤旁路的调节。这将通过确定如何绕过 复合体在停止的复制分叉处组装，并通过确定该组装如何 由PCNA泛素化酶控制。第二，我们将研究 跨损伤合成这将通过确定如何最适当的非经典 选择聚合酶来绕过损伤，并通过确定每个非经典的 聚合酶容纳受损的DNA模板。第三，我们将研究 模板切换这将通过确定复制分叉的重构如何 允许绕过DNA损伤，并通过确定这一过程如何进行， 叉状重塑DNA解旋酶。在回答这些问题时，我们将获得重要的新信息。 对维持基因组稳定性的见解。

Project Summary/Abstract DNA damage is a serious threat to genome stability. This is because it interferes with DNA replication leading to mutations and chromosomal rearrangements – the hallmarks of cancer, aging, and other diseases. To ensure genome stability, cells utilize DNA damage bypass pathways to cope with DNA damage during replication. The long-term goal of our research program is to understand how DNA damage bypass is carried out in eukaryotic systems at the structural and mechanistic level. Our research will focus on two damage bypass pathways: translesion synthesis and template switching. Progress in this field has slowed recently because of the challenges associated with studying how the various bypass components assemble into and function within large, dynamic, multi-protein complexes. We have developed the biochemical, biological, biophysical, computational, and structural tools needed to overcome these challenges. This puts us in a unique position to answer many fundamental questions about damage bypass. Our future research plan is organized into three broad projects. First, we will study the regulation of DNA damage bypass. This will be done by determining how bypass complexes are assembled at stalled replication forks and by determining how this assembly is controlled by PCNA-ubiquitylating enzymes. Second, we will study the mechanisms of translesion synthesis. This will be done by determining how the most appropriate non-classical polymerase is chosen to bypass the damage and by determining how each non-classical polymerase accommodates damaged DNA templates. Third, we will study the mechanisms of template switching. This will be done by determining how the remodeling of the replication fork allows for the bypass of DNA damage and by determining how this process is carried out by fork-remodeling DNA helicases. In answering these questions, we will gain important new insights into the maintenance of genome stability.