Complementary strand relocation may play vital roles in RecA-based homology recognition.
Complementary strand relocation may play vital roles in RecA-based homology recognition.
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DOI：
10.1093/nar/gks769
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发表时间：
2012-11-01
影响因子：
14.9
通讯作者：
Prentiss M
中科院分区：
文献类型：
--
作者：
Peacock-Villada A;Yang D;Danilowicz C;Feinstein E;Pollock N;McShan S;Coljee V;Prentiss M
RecA家族蛋白通过同源搜索和链交换介导同源重组和重组DNA修复。最初，蛋白质与进入的单链DNA（ssDNA）形成细丝，结合在位点I中。RecA-ssDNA丝然后在位点II结合双链DNA（dsDNA）。非同源dsDNA快速解结合，而同源dsDNA经历链交换，在位点I产生异源双链体dsDNA，在位点II产生剩余的外链。我们表明，施加力的互补链的末端显着延迟链交换，而施加相同的力的传出链不。我们还表明，晶体学确定的结合位点的位置需要一个中间结构，除了初始和最终的结构。此外，我们证明，由于链交换和自由RecA结合的特征dsDNA延伸率是相同的，这表明互补链从其在中间结构中的位置到其在最终结构中的位置的重新定位限制了这两种速率。最后，我们提出，同源性识别是由过渡到和从中间结构，其中的过渡依赖于在dsDNA的差异延伸。这种差异延伸驱动同系物的链交换向前，并增加非同系物的链交换的自由能罚分。
RecA-family proteins mediate homologous recombination and recombinational DNA repair through homology search and strand exchange. Initially, the protein forms a filament with the incoming single-stranded DNA (ssDNA) bound in site I. The RecA–ssDNA filament then binds double-stranded DNA (dsDNA) in site II. Non-homologous dsDNA rapidly unbinds, whereas homologous dsDNA undergoes strand exchange yielding heteroduplex dsDNA in site I and the leftover outgoing strand in site II. We show that applying force to the ends of the complementary strand significantly retards strand exchange, whereas applying the same force to the outgoing strand does not. We also show that crystallographically determined binding site locations require an intermediate structure in addition to the initial and final structures. Furthermore, we demonstrate that the characteristic dsDNA extension rates due to strand exchange and free RecA binding are the same, suggesting that relocation of the complementary strand from its position in the intermediate structure to its position in the final structure limits both rates. Finally, we propose that homology recognition is governed by transitions to and from the intermediate structure, where the transitions depend on differential extension in the dsDNA. This differential extension drives strand exchange forward for homologs and increases the free energy penalty for strand exchange of non-homologs.
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影响因子：
11.4
作者：
Fulconis, Renaud;Mine, Judith;Viovy, Jean-Louis
通讯作者：
Viovy, Jean-Louis
影响因子：
3.7
作者：
Fan, Hsiu-Fang;Cox, Michael M.;Li, Hung-Wen
通讯作者：
Li, Hung-Wen
影响因子：
64.8
作者：
Galletto, Roberto;Amitani, Ichiro;Kowalczykowski, Stephen C.
通讯作者：
Kowalczykowski, Stephen C.
DOI：
10.1016/s1296-2147(01)01287-2
发表时间：
2001-12-01
期刊：
COMPTES RENDUS DE L ACADEMIE DES SCIENCES SERIE IV PHYSIQUE ASTROPHYSIQUE
影响因子：
--
作者：
De Gennes, PG
通讯作者：
De Gennes, PG
影响因子：
5.6
作者：
MULLER, B;KOLLER, T;STASIAK, A
通讯作者：
STASIAK, A