Department of Biotechnology, Indian Institute of Technology Hyderabad, Kandi, Sangareddy, 502285, India.
DNA Repair (Amst). 2020 Mar;87:102804. doi: 10.1016/j.dnarep.2020.102804. Epub 2020 Jan 20.
Cellular processes, such as DNA replication, recombination and transcription, require DNA strands separation and single-stranded DNA is formation. The single-stranded DNA is promptly wrapped by human single-stranded DNA binding proteins, replication protein A (RPA) complex. RPA binding not only prevent nuclease degradation and annealing, but it also coordinates cell-cycle checkpoint activation and DNA repair. However, RPA binding offers little protection against the chemical modification of DNA bases. This review focuses on the type of DNA base damage that occurs in single-stranded DNA and how the damage is rectified in human cells. The discovery of DNA repair proteins, such as ALKBH3, AGT, UNG2, NEIL3, being able to repair the damaged base in the single-stranded DNA, renewed the interest to study single-stranded DNA repair. These mechanistically different proteins work independently from each other with the overarching goal of increasing fidelity of recombination and promoting error-free replication.
细胞过程，如 DNA 复制、重组和转录，需要 DNA 链的分离和单链 DNA 的形成。单链 DNA 迅速被人单链 DNA 结合蛋白，复制蛋白 A（RPA）复合物包裹。RPA 结合不仅可以防止核酸酶降解和退火，还可以协调细胞周期检验点的激活和 DNA 修复。然而，RPA 结合对 DNA 碱基的化学修饰提供的保护作用很小。本综述重点介绍了单链 DNA 中发生的 DNA 碱基损伤的类型，以及人类细胞如何修复损伤。发现 DNA 修复蛋白，如 ALKBH3、AGT、UNG2、NEIL3，能够修复单链 DNA 中的损伤碱基，这重新激发了人们对单链 DNA 修复的研究兴趣。这些机制不同的蛋白彼此独立工作，总体目标是提高重组的保真度，促进无错误复制。
