Solinger J A, Heyer W D
Division of Biological Sciences, Section of Microbiology, University of California, Davis, CA 95616, USA.
Proc Natl Acad Sci U S A. 2001 Jul 17;98(15):8447-53. doi: 10.1073/pnas.121009898.
Rad54 and Rad51 are important proteins for the repair of double-stranded DNA breaks by homologous recombination in eukaryotes. As previously shown, Rad51 protein forms nucleoprotein filaments on single-stranded DNA, and Rad54 protein directly interacts with such filaments to enhance synapsis, the homologous pairing with a double-stranded DNA partner. Here we demonstrate that Saccharomyces cerevisiae Rad54 protein has an additional role in the postsynaptic phase of DNA strand exchange by stimulating heteroduplex DNA extension of established joint molecules in Rad51/Rpa-mediated DNA strand exchange. This function depended on the ATPase activity of Rad54 protein and on specific protein:protein interactions between the yeast Rad54 and Rad51 proteins.
Rad54和Rad51是真核生物中通过同源重组修复双链DNA断裂的重要蛋白质。如前所示,Rad51蛋白在单链DNA上形成核蛋白细丝,而Rad54蛋白直接与这些细丝相互作用以增强联会,即与双链DNA伙伴的同源配对。在这里,我们证明酿酒酵母Rad54蛋白在DNA链交换的突触后阶段具有额外作用,即通过刺激Rad51/Rpa介导的DNA链交换中已建立的连接分子的异源双链DNA延伸。该功能依赖于Rad54蛋白的ATP酶活性以及酵母Rad54和Rad51蛋白之间特定的蛋白质-蛋白质相互作用。