Rad54 protein is targeted to pairing loci by the Rad51 nucleoprotein filament
Rad54 protein is targeted to pairing loci by the Rad51 nucleoprotein filament
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DOI：
10.1016/s1097-2765(00)00057-5
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发表时间：
2000-09-01
期刊：
影响因子：
16
通讯作者：
Kowalczykowski, SC
中科院分区：
文献类型：
--
作者：
Mazin, AV;Bornarth, CJ;Kowalczykowski, SC
RAD51和RAD54蛋白在真核生物通过同源重组修复双链DNA(DsDNA)断裂过程中起重要作用。RAD51组装在单链DNA(SsDNA)上形成螺旋核蛋白细丝，与dsDNA进行同源配对；Rad54实质上刺激了这种配对。在这里，我们证明了Rad54与成熟的RAD51-ssDNA细丝协同作用。RAD54对DNA配对的促进作用在与RAD51的等摩尔比时最大。反过来，RAD51-ssDNA细丝增强了Rad54的dsDNA依赖的ATPase和dsDNA解离活性。我们得出结论，Rad54作为RAD51-核蛋白细丝的一部分参与DNA同源性搜索，并且该细丝将Rad54运送到dsDNA配对位点，从而将潜在靶DNA的解离与同源性搜索过程联系起来。
Rad51 and Rad54 proteins are important for the repair of double-stranded DNA (dsDNA) breaks by homologous recombination in eukaryotes. Rad51 assembles on single-stranded DNA (ssDNA) to form a helical nucleoprotein filament that performs homologous pairing with dsDNA; Rad54 stimulates this pairing substantially. Here, we demonstrate that Rad54 acts in concert with the mature Rad51-ssDNA filament. Enhancement of DNA pairing by Rad54 is greatest at an equimolar ratio relative to Rad51 within the filament. Reciprocally, the Rad51-ssDNA filament enhances both the dsDNA-dependent ATPase and the dsDNA unwinding activities of Rad54. We conclude that Rad54 participates in the DNA homology search as a component of the Rad51-nucleoprotein filament and that the filament delivers Rad54 to the dsDNA pairing locus, thereby linking the unwinding of potential target DNA with the homology search process.