Molecular events regulated by the Ku heterodimer in non-homologous end-joining and DNA damage signaling pathways

非同源末端连接和 DNA 损伤信号通路中 Ku 异二聚体调控的分子事件

• 批准号: RGPIN-2018-05518
• 负责人: SchildPoulter, Caroline
• 金额: $ 3.64万
• 依托单位: University of Western Ontario
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=713716
• 关键词: Molecular; events; regulated; Ku; heterodimer

Ku is an abundant, ubiquitous factor that has been remarkably conserved throughout evolution as it has been identified in all organisms from bacteria to man. Ku is a complex of two proteins that plays an essential role in the repair of double-strand DNA breaks, a form of DNA damage in which both strands of the double helix break, leading to chromosome rearrangements and, ultimately, genomic instability. While it is understood that Ku is essential for the proper repair of DNA, its mode of action is still unclear. It is known that Ku interacts with a number of other factors that play roles in the repair of DNA, however, the details and the outcome of these interactions are poorly understood. Using the crystal structure of Ku that was recently made available, we can predict regions of the protein that are accessible to contact other proteins. Thus we have made mutations in several of these accessible regions to test if they alter Ku DNA repair functions. We have identified two Ku mutations that alter its ability to function in response to DNA damage. We found that these mutations result in different defects suggesting that the mutated regions are involved in distinct functions. We propose to identify the proteins that interact with these Ku motifs and elucidate how they function together in the repair of DNA. In the long-term, these analyses will enhance our understanding of the functions of Ku in the mechanisms that are set in place to deal with double-stranded DNA breaks.

Ku是一种丰富的、无处不在的因子，在整个进化过程中一直被显著地保守着， Ku是一种由两种蛋白质组成的复合物，在生物体内起着至关重要的作用。 修复双链DNA断裂，这是一种DNA损伤形式，其中双螺旋的两条链 断裂，导致染色体重排，最终导致基因组不稳定。 虽然Ku对DNA的正常修复至关重要，但其作用方式仍不清楚。是 已知Ku与许多在DNA修复中起作用的其他因子相互作用，然而， 对这些相互作用的细节和结果知之甚少。 使用最近可用的Ku的晶体结构，我们可以预测蛋白质的区域， 与其他蛋白质接触。因此，我们在这些可接近区域中的几个区域进行了突变，以测试 如果它们改变了库族DNA的修复功能我们已经确定了两个Ku突变，改变了它在细胞中发挥作用的能力。 DNA损伤的反应。我们发现这些突变导致不同的缺陷，这表明突变的 区域参与不同的功能。我们建议鉴定与这些Ku基序相互作用的蛋白质 并阐明它们如何在DNA修复中共同发挥作用。 从长远来看，这些分析将有助于我们更好地理解Ku在以下机制中的作用： 用来处理双链DNA断裂