An 'open' structure of the RecOR complex supports ssDNA binding within the core of the complex.
An 'open' structure of the RecOR complex supports ssDNA binding within the core of the complex.
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DOI：
10.1093/nar/gkt572
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发表时间：
2013-09
影响因子：
14.9
通讯作者：
Timmins J
中科院分区：
文献类型：
--
作者：
Radzimanowski J;Dehez F;Round A;Bidon-Chanal A;McSweeney S;Timmins J
有效的DNA修复对于细胞存活和维持基因组完整性至关重要。同源重组途径负责细胞内DNA双链断裂的修复。细菌中该途径的启动可以通过RecBCD或RecFOR蛋白进行。RecFOR途径中的一个重要调控参与者是RecOR复合物，其促进RecA加载到DNA上。在这里，我们报告了关于耐辐射奇球菌RecOR的组装及其与DNA的相互作用的新数据，为RecOR在同源重组中的作用模式提供了新的机制见解。我们提出了一个更高分辨率的晶体结构的RecOR在一个“开放”的构象，其中的四聚体RecR环两侧的两个RecO分子是可访问的DNA结合。我们使用小角中子散射和诱变研究表明，DNA结合确实发生在RecR环内。单链DNA的结合发生时，RecOR复合物没有任何重大的构象变化，而在双链DNA结合时观察到结构重排。最后，我们的分子动力学模拟，我们的生化数据的支持下，提供了一个详细的图片的DNA结合基序的RecOR和揭示，单链DNA夹在两个面对的寡核苷酸结合结构域的RecR环内的RecO。
Efficient DNA repair is critical for cell survival and the maintenance of genome integrity. The homologous recombination pathway is responsible for the repair of DNA double-strand breaks within cells. Initiation of this pathway in bacteria can be carried out by either the RecBCD or the RecFOR proteins. An important regulatory player within the RecFOR pathway is the RecOR complex that facilitates RecA loading onto DNA. Here we report new data regarding the assembly of Deinococcus radiodurans RecOR and its interaction with DNA, providing novel mechanistic insight into the mode of action of RecOR in homologous recombination. We present a higher resolution crystal structure of RecOR in an ‘open’ conformation in which the tetrameric RecR ring flanked by two RecO molecules is accessible for DNA binding. We show using small-angle neutron scattering and mutagenesis studies that DNA binding does indeed occur within the RecR ring. Binding of single-stranded DNA occurs without any major conformational changes of the RecOR complex while structural rearrangements are observed on double-stranded DNA binding. Finally, our molecular dynamics simulations, supported by our biochemical data, provide a detailed picture of the DNA binding motif of RecOR and reveal that single-stranded DNA is sandwiched between the two facing oligonucleotide binding domains of RecO within the RecR ring.
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影响因子：
64.8
作者：
Cox, MM;Goodman, MF;Marians, KJ
通讯作者：
Marians, KJ
DOI：
10.1107/s0907444904019158
发表时间：
2004-12-01
影响因子：
2.2
作者：
Emsley, P;Cowtan, K
通讯作者：
Cowtan, K
影响因子：
11.4
作者：
Lee, BI;Kim, KH;Suh, SW
通讯作者：
Suh, SW
强大的体积溶剂校正和各向异性缩放程序。
DOI：
10.1107/s0907444905007894
发表时间：
2005-07
期刊：
Acta crystallographica. Section D, Biological crystallography
影响因子：
--
作者：
Afonine PV;Grosse-Kunstleve RW;Adams PD
通讯作者：
Adams PD
影响因子：
4.4
作者：
FELLER, SE;ZHANG, YH;BROOKS, BR
通讯作者：
BROOKS, BR