Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, Philadelphia, PA 19102, USA.
DNA Repair (Amst). 2010 Mar 2;9(3):286-302. doi: 10.1016/j.dnarep.2009.12.006. Epub 2010 Jan 20.
Homologous recombination (HR) performs crucial functions including DNA repair, segregation of homologous chromosomes, propagation of genetic diversity, and maintenance of telomeres. HR is responsible for the repair of DNA double-strand breaks and DNA interstrand cross-links. The process of HR is initiated at the site of DNA breaks and gaps and involves a search for homologous sequences promoted by Rad51 and auxiliary proteins followed by the subsequent invasion of broken DNA ends into the homologous duplex DNA that then serves as a template for repair. The invasion produces a cross-stranded structure, known as the Holliday junction. Here, we describe the properties of Rad54, an important and versatile HR protein that is evolutionarily conserved in eukaryotes. Rad54 is a motor protein that translocates along dsDNA and performs several important functions in HR. The current review focuses on the recently identified Rad54 activities which contribute to the late phase of HR, especially the branch migration of Holliday junctions.
同源重组（HR）执行包括 DNA 修复、同源染色体分离、遗传多样性传播和端粒维持在内的关键功能。HR 负责修复 DNA 双链断裂和 DNA 链间交联。HR 的过程始于 DNA 断裂和缺口处，涉及由 Rad51 和辅助蛋白促进的同源序列搜索，随后断裂的 DNA 末端侵入同源双链 DNA，然后该 DNA 作为修复的模板。入侵产生了一种称为 Holliday 连接的交错链结构。在这里，我们描述了 Rad54 的特性，Rad54 是一种重要且多功能的 HR 蛋白，在真核生物中具有进化保守性。Rad54 是一种沿着 dsDNA 迁移的运动蛋白，在 HR 中执行几个重要功能。本综述重点介绍了最近确定的 Rad54 活性，这些活性有助于 HR 的后期阶段，特别是 Holliday 连接的分支迁移。
