Molecular machinery of the bacterial nucleotide excision repair pathway

这个项目的目标是了解细胞如何修复受损的DNA。DNA修复过程对于确保DNA基因组中的遗传信息保持完好至关重要。在细胞内部，DNA不断受到多种来源的攻击，包括它的水环境、新陈代谢产生的化学物质，或者暴露在外部辐射或毒素中。为了保护DNA，细胞进化了生物化学过程，巡逻基因组，检测损伤，并组织反应，旨在恢复DNA的完整性。这个项目的重点是一个这样的修复过程，称为核苷酸切除修复，在这个过程中，受损的DNA片段被移除，并用正常的DNA取代。这项工作将在细菌中进行，但由于DNA修复机制在包括人类在内的高等生物体中类似，因此这一结果应该会产生广泛的科学影响。该项目还将通过让本科生参与研究和创意艺术的项目，以及与纽约市公立学校的接触，产生教育影响。这些教育活动将有助于完成两大使命：一是帮助科学家吸引和留住科学、技术、工程和数学(STEM)领域的学生；二是帮助纽约城市学院为纽约市的儿童、移民、少数族裔和那些没有经济能力的人提供高质量和负担得起的教育。DNA修复是致力于维护遗传信息的基本过程，然而DNA修复的许多机械细节仍然不清楚。这项研究将填补我们对DNA修复途径--细菌核苷酸切除修复--的理解空白。以前的研究确定了三种蛋白质UvrA、UvrB和UvrC的作用，它们通过一系列大型和动态的多蛋白复合体发挥作用。通过应用生化、生物物理和结构方法，实验将测试基于结构的模型的三种机制：1)从天然DNA背景中识别受损DNA，2)核苷酸结合和水解，以及3)UvrA和UvrB在含有病变的DNA上的分子编排。这些结果有望为核苷酸切除修复如何在基因组监测和修复的背景下发生提供新的见解。此外，这一知识将影响我们对其他细胞活动的看法，包括DNA复制、基因表达、进化过程以及细胞凋亡、衰老和肿瘤发生的细胞过程。该奖项由生物科学局分子和细胞生物科学部的遗传机制和分子生物物理学项目共同资助。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

The goal of this project is to understand how cells repair damaged DNA. The process of DNA repair is essential to ensure that the genetic information in the DNA genome remains intact. Inside cells, DNA is continually under assault from multiple sources, including its watery environment, chemicals produced by metabolism, or exposure to external radiation or toxins. To protect the DNA, cells have evolved biochemical processes that patrol the genome, detect damage, and organize responses aimed at restoring the integrity of the DNA. This project focuses on one such repair process, called nucleotide excision repair, in which damaged segments of DNA are removed and replaced with normal DNA. This work will be carried out in bacteria, but because DNA repair mechanisms are similar in higher organisms, including humans, the results should have wide-ranging scientific impact. The project also will have educational impact through programs for engaging undergraduates in research and creative arts and for outreach to public schools in New York City. These educational activities will help fulfill two broad missions: for scientists to attract and retain students in science, technology, engineering, and mathematics (STEM) fields, and for the City College of New York to provide a high-quality and affordable education to children of New York City, immigrants, minorities, and those without economic means. DNA repair is a fundamental process dedicated to maintenance of genetic information, yet many mechanistic details of DNA repair remain obscure. This research will fill gaps in our understanding of one DNA repair pathway, bacterial nucleotide excision repair. Previous research established roles for three proteins, UvrA, UvrB, and UvrC, which function via a series of large and dynamic multi-protein complexes. By applying biochemical, biophysical, and structural approaches, experiments will test structure-based models for three mechanisms: 1) identification of damaged DNA from a background of native DNA, 2) nucleotide binding and hydrolysis, and 3) the molecular choreography of UvrA and UvrB on lesion-containing DNA. The results are expected to provide new insights into how nucleotide excision repair occurs in the context of genome surveillance and repair. Moreover, this knowledge will influence our views of other cellular activities, including DNA replication, gene expression, evolutionary processes and the cellular processes of apoptosis, senescence, and tumorigenesis.This award is co-funded by the Genetic Mechanisms and the Molecular Biophysics programs in the Division of Molecular and Cellular Biosciences in the Directorate for Biological Sciences.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.