Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, Philadelphia, PA 19102-1192, USA.
Methods. 2010 Jul;51(3):336-46. doi: 10.1016/j.ymeth.2010.02.010. Epub 2010 Feb 16.
The Holliday junction is a key intermediate of DNA repair, recombination, and replication. Branch migration of Holliday junctions is a process in which one DNA strand is progressively exchanged for another. Branch migration of Holliday junctions may serve several important functions such as affecting the length of genetic information transferred between homologous chromosomes during meiosis, restarting stalled replication forks, and ensuring the faithful repair of double strand DNA breaks by homologous recombination. Several proteins that promote branch migration of Holliday junctions have been recently identified. These proteins, which function during DNA replication and repair, possess the ability to bind Holliday junctions and other branched DNA structures and drive their branch migration by translocating along DNA in an ATPase-dependent manner. Here, we describe methods employing a wide range of DNA substrates for studying proteins that catalyze branch migration of Holliday junctions.
Holliday 连接点是 DNA 修复、重组和复制的关键中间体。Holliday 连接点的分支迁移是一个 DNA 链逐渐被另一个 DNA 链取代的过程。Holliday 连接点的分支迁移可能具有多种重要功能,例如影响减数分裂过程中同源染色体之间遗传信息的转移长度、重新启动停滞的复制叉、并通过同源重组确保双链 DNA 断裂的忠实修复。最近已经鉴定出几种促进 Holliday 连接点分支迁移的蛋白质。这些在 DNA 复制和修复过程中发挥作用的蛋白质能够结合 Holliday 连接点和其他分支 DNA 结构,并通过 ATP 依赖性方式沿着 DNA 易位来驱动其分支迁移。在这里,我们描述了使用广泛的 DNA 底物来研究催化 Holliday 连接点分支迁移的蛋白质的方法。