Administrative supplement to support investigation into the structural basis of ubiquitin signaling in response to DNA alkylation damage

项目总结/摘要 DNA烷基化损伤包括一类普遍的、有害的核碱基修饰， 由于内源性和外源性来源，人体内每个细胞每天的时间为。如果没有修复， DNA烷基化损伤可导致基因突变、DNA复制抑制和细胞死亡。几 DNA修复途径已经发展到逆转由烷基化引起的许多DNA修饰 损害虽然这些途径中的修复酶已经得到了很好的研究，但对上游的修复酶却知之甚少。 启动DNA修复并将修复复合物定位于损伤位点的信号传导事件。最近显示 ALKBH 3-ASCC DNA修复复合物被ALKBH 3-ASCC DNA修复复合物的结合链募集到烷基化损伤位点。 在DNA损伤附近组装的蛋白质泛素。ASCC 2蛋白负责 结合定位ALKBH 3-ASCC复合物的多聚泛素链。大量不同类型的 然而，细胞中存在多聚泛素链，ASCC 2如何选择性地识别K63-泛素链尚不清楚。 连接的多聚泛素链，信号烷基化损伤。PI建议使用结构组合 生物学、细胞生物学和生物物理学研究ASCC 2对K63连接的多聚泛素链的选择性， ALKBH 3-ASCC复合物定位对ASCC 2独特的泛素结合特性的依赖性。 该项目的具体目标是：1）鉴定新的ASCC 2：泛素结合界面， 对多聚泛素链的亲和力增强，2）确定ASCC 2结合特异性的结构基础 K63连接的多聚泛素链，以及3）量化ASCC 2的泛素结合特性对 DNA烷基化损伤修复。DNA烷基化损伤相关问题的研究 修复将使临床医生能够更好地了解由烷基化损伤修复缺陷引起的疾病 本发明的目的是提供一种用于治疗癌症的方法，该方法用于治疗癌症途径，并且更有效地将烷化剂用作治疗剂，特别是用于治疗癌症。 此外，这些实验也将提供宝贵的研究机会，在圣山的学生。 玛丽大学（MSMU），其中生物，化学和生物化学专业的大量人口 第一代大学生（16.7%），有色人种学生（42.5%），或来自中等或低收入家庭的学生 家庭（27.1%的佩尔助学金获得者）。总的来说，拟议的实验将解决缺乏知识的问题， 目前对DNA烷基化损伤修复的理解，同时大大提高了研究机会， MSMU的学生

Project Summary/Abstract DNA alkylation damage comprises a class of prevalent, harmful nucleobase modifications that occur thousands of times per cell per day in the human body as a result of endogenous and exogenous sources. Left unrepaired, DNA alkylation damage can result in genetic mutations, the inhibition of DNA replication, and cell death. Several DNA repair pathways have evolved to reverse the numerous DNA modifications that result from alkylation damage. While the repair enzymes in these pathways are well studied, much less is known about the upstream signaling events that initiate DNA repair and localize repair complexes to damage sites. It was recently shown that the ALKBH3-ASCC DNA repair complex is recruited to alkylation damage sites by binding chains of the protein ubiquitin that are assembled in proximity to the DNA lesions. The protein ASCC2 is responsible for binding the polyubiquitin chains that localize the ALKBH3-ASCC complex. A vast array of different types of polyubiquitin chains are present in cells, however, and it is unclear how ASCC2 selectively recognizes the K63- linked polyubiquitin chains that signal alkylation damage. The PI proposes to use a combination of structural biology, cell biology, and biophysics to investigate ASCC2’s selectivity for K63-linked polyubiquitin chains and the dependence of ALKBH3-ASCC complex localization on the unique ubiquitin-binding properties of ASCC2. The specific aims of the project are: 1) to identify the novel ASCC2:ubiquitin binding interface that imparts enhanced affinity for polyubiquitin chains, 2) to determine the structural basis of ASCC2’s specificity for binding K63-linked polyubiquitin chains, and 3) to quantify the contribution of ASCC2’s ubiquitin-binding properties to DNA alkylation damage repair. Investigating the outstanding questions associated with DNA alkylation damage repair will allow clinicians to better understand diseases that result from defects in alkylation damage repair pathways and to more effectively deploy alkylating agents as therapeutics, especially for the treatment of cancer. Furthermore, these experiments will also provide valuable research opportunities for students at Mount St. Mary’s University (MSMU), where substantial populations of the biology, chemistry, and biochemistry majors are first-generation college students (16.7%), students of color (42.5%), or students from moderate- or low-income families (27.1 % Pell Grant recipients). Overall, the proposed experiments will address a lack of knowledge in the current understanding of DNA alkylation damage repair while greatly enhancing research opportunities for students at MSMU.