Functional cross-talk among Rad51, Rad54, and replication protein A in heteroduplex DNA joint formation
Functional cross-talk among Rad51, Rad54, and replication protein A in heteroduplex DNA joint formation
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DOI：
10.1074/jbc.m205864200
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发表时间：
2002-11-15
影响因子：
4.8
通讯作者：
Sung, P
中科院分区：
文献类型：
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作者：
Van Komen, S;Petukhova, G;Sung, P
酿酒酵母RAD51、RAD54和复制蛋白A(RPA)蛋白在同源重组过程中协同作用形成异源双链DNA关节。对于质粒长的DNA底物，当RAD51的量时，DNA关节的形成最大。大大低于饱和起始单链DNA模板所需的量，并且相对于RAD51，仅需要催化量的Rad54。RPA对于最佳反应效率仍然是必不可少的，但在这种情况下，它的作用是隔离游离单链DNA，否则会抑制RAD51和Rad54的功能。我们还证明了Rad54有助于克服DNA联合形成中的各种反应限制。这些结果揭示了Rad54在RAD51介导的同源DNA配对反应中的作用，也揭示了RPA在该反应的突触前阶段的新作用。
Saccharomyces cerevisiae Rad51, Rad54, and replication protein A (RPA) proteins work in concert to make heteroduplex DNA joints during homologous recombination. With plasmid length DNA substrates, maximal DNA joint formation is observed with amounts of Rad51. substantially below what is needed to saturate the initiating single-stranded DNA template, and, relative to Rad51, Rad54 is needed in only catalytic quantities. RPA is still indispensable for optimal reaction efficiency, but its role in this instance is to sequester free single-stranded DNA, which otherwise inhibits Rad51 and Rad54 functions. We also demonstrate that Rad54 helps overcome various reaction constraints in DNA joint formation. These results thus shed light on the function of Rad54 in the Rad51-mediated homologous DNA pairing reaction and also reveal a novel role of RPA in the presynaptic stage of this reaction.