Cellular requirements for Pol theta function

项目摘要 本计画将探讨哺乳动物DNA聚合酶θ（Pol θ），DNA修复的定义酵素 通过聚合酶θ介导的末端连接（TMEJ）的双链断裂。这是项目1（“蜂窝 Pol θ的要求”），这是一个名为“聚合酶θ，基因组不稳定性， 癌症”。 TMEJ的机制和生物学作用尚不清楚。重要的是，Pol θ的损失在正常人中是可以耐受的。 细胞，但在许多癌症中是致命的，使其成为癌症治疗的一个有吸引力的目标。不幸的是少校 在Pol θ的作用机制和生物学作用方面的知识空白削弱了发展 安全有效的目标定位策略 项目1将通过利用现有的专门细胞测定和 用于识别遗传相互作用的强大平台。我们还将开发新的方法来探测 Pol θ在细胞修复中的不同作用。 该项目旨在填补知识方面的几个主要空白： 在目标1中，“我们将确定蜂窝TMEJ的要求”。我们将使用特定Pol缺陷的细胞系， q活动和其他因素与TMEJ，并评估这些缺陷对细胞TMEJ的影响。 在目标2“我们将确定参与TMEJ的细胞环境”。我们将评估阻止的程度 另一条修复途径中的晚期步骤参与TMEJ（2A）。我们还将采用高通量测序， 研究Pol θ缺失对化疗剂引起的基因组瘢痕的影响（2B）。 在目标3中，“我们将采用遗传筛选来识别TMEJ的新介质”。我们将鉴定一组基因， 与Pol θ相同的途径，通过发现那些基因，当突变时，在一组缺陷的细胞中是致命的， 其他修复途径，使他们严重依赖TMEJ生存。 研究工作将在计划项目内与其他三个项目和 三个核心我们结合了多种方法，包括分子生物学，生物化学，结构生物学， 生物物理学我们将使用突变体，并根据与项目2、3和4共享的结果启动实验， 这将通过核心A的反馈进行持续监控。核心B将支持蛋白纯化， 和细胞系构建。

PROJECT SUMMARY This project will investigate mammalian DNA polymerase θ (Pol θ), the defining enzyme for repair of DNA double-strand breaks by polymerase theta-mediated end joining (TMEJ). This is Project 1 (“Cellular requirements for Pol θ”) which is part of a Program Project titled, “Polymerase theta, genome instability, and cancer”. TMEJ mechanism and biological role is not well understood. Importantly, loss of Pol θ is tolerated in normal cells but is lethal in many cancers, making it an attractive target for cancer therapy. Unfortunately, the major knowledge gaps in both the mechanism of action and biological role for Pol θ have undercut the development of safe, effective targeting strategies. Project 1 will identify requirements for Pol θ function by leveraging existing specialized cellular assays and a robust platform for identifying genetic interactions. We will additionally develop new methods to probe the different roles of Pol θ in cellular repair. This project aims to fill several major gaps in knowledge: In Aim 1 “We will identify requirements for cellular TMEJ”. We will use cell lines defective in specific Pol q activities and other factors linked to TMEJ, and assess the impact of these defects on cellular TMEJ. In Aim 2 “We will determine cellular contexts that engage TMEJ”. We will assess the extent to which blocks to late steps in another repair pathway engage TMEJ (2A). We will also employ high throughput sequencing to investigate the impact of Pol θ loss on genomic scars caused by a chemotherapeutic agent (2B). In Aim 3 “We will employ a genetic screen to identify new mediators of TMEJ”. We will identify a set of genes in the same pathway as Pol θ, by finding those genes that when mutated are lethal in a panel of cells defective in other repair pathways that renders them acutely dependent on TMEJ for survival. The research work will be highly coordinated within the Program Project with the other three Projects and the three Cores. Our combined diverse approaches include molecular biology, biochemistry, structural biology, and biophysics. We will employ mutants and initiate experiments based on results shared with projects 2, 3, and 4, which will be constantly monitored with feedback via Core A. Protein purification will be supported by Core B, and cell line construction by Core C.