CAREER: Understanding the Non-proteolytic Function of Ubiquitin in Eukaryotic Translesion DNA Synthesis

泛素和泛素样蛋白在许多基本的重要细胞过程中具有不同的功能。除了已知的泛素在26S蛋白酶体介导的蛋白质降解途径中的作用外，泛素的非蛋白水解性作用正在迅速被发现。特别是，DNA损伤反应领域的研究人员在过去十年中见证了快速的进步。这在很大程度上是由开创性的发现刺激的，即关键的DNA复制/修复蛋白--增殖细胞核抗原(增殖细胞核抗原)的泛素化和SUMO化精确地控制着细胞如何对不同类型的DNA损伤做出反应，以及如何选择不同的DNA损伤修复或耐受途径来应对DNA损伤。这个职业项目的目标有两个：开发有效的泛素化的增殖细胞核抗原的化学方法，以及使用泛素化的增殖细胞核抗原来研究模式生物酿酒酵母跨损伤DNA合成的分子机制。这些信息还将帮助其他领域的研究人员破译泛素在基本细胞过程中的非蛋白分解功能。此外，新开发的泛素化化学方法可以推广到其他涉及泛素或泛素样蛋白翻译后修饰的过程的研究。更广泛的影响这个职业项目旨在激发高中生和化学和生物领域未被充分代表的少数群体的科学好奇心和职业抱负。研究和教育活动的跨学科性质将使本科生和研究生在新兴的化学生物学领域获得新的想法和最新的实验技能。外联活动还将加强机构基础设施(特拉华州生物技术研究所的虚拟现实可视化或CAVE系统)，这不仅将使研究界受益，也将使普通公众受益。将与匈牙利科学院遗传学研究所建立长期伙伴关系，以促进合作努力，解决DNA损伤应对中的这一极具挑战性的问题。该项目的最终目标是建立研究和教育计划，不仅通过提高对DNA损伤耐受性的科学理解来促进化学生物学领域的发展，而且还激励和教育下一代化学生物学家。

Ubiquitin and ubiquitin-like proteins have diverse functions in many fundamentally important cellular processes. Besides the well-known role of ubiquitin in the 26S proteasome-mediated protein degradation pathway, the non-proteolytic roles of ubiquitin are being uncovered at a fast pace. In particular, researchers in the area of DNA damage response have witnessed rapid progress within the past decade. This was largely stimulated by the seminal findings that ubiquitylation and SUMOylation of a key DNA replication/repair protein, proliferating cell nuclear antigen (PCNA), controls precisely how cells respond to different types of DNA damage, and how the different DNA damage repair or tolerance pathways are chosen to cope with the DNA damage. The objective of this CAREER project is twofold: developing chemical approaches for efficient ubiquitylation of PCNA, and using the ubiquitylated PCNA to investigate the molecular mechanism of translesion DNA synthesis in the model organism Saccharomyces cerevisiae. This information will also help researchers in other fields to decipher the non-proteolytic function of ubiquitin in essential cellular processes. Moreover, the newly developed chemical approaches for ubiquitylation can be generalized for investigation of other processes that involve post-translational modification by ubiquitin or ubiquitin-like proteins. Broader ImpactThis CAREER project seeks to spark the scientific curiosity and career aspirations of high school students and underrepresented minorities in chemistry and biology. The interdisciplinary nature of the research and educational activities will equip the undergraduate and graduate students with novel ideas and the most up-to-date experimental skills in the burgeoning field of chemical biology. The outreach activities will also enhance the institutional infrastructure (the virtual reality visualization or CAVE system at the Delaware Biotechnology Institute) that will benefit not only the research community but also the general public. A long-term partnership will be established with the Institute of Genetics, Hungarian Academy of Sciences to facilitate a collaborative effort in attacking this very challenging problem in the DNA damage response. The ultimate goal of this project is to establish research and educational programs that not only advance the field of chemical biology by enhancing the scientific understanding of DNA damage tolerance, but also inspire and educate the next generation of chemical biologists.