RAD51AP1 mediates RAD51 activity through nucleosome interaction.
RAD51AP1 mediates RAD51 activity through nucleosome interaction.
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DOI：
10.1016/j.jbc.2021.100844
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发表时间：
2021-07
期刊：
影响因子：
--
通讯作者：
Wiese C
中科院分区：
文献类型：
--
作者：
Pires E;Sharma N;Selemenakis P;Wu B;Huang Y;Alimbetov DS;Zhao W;Wiese C
RAD 51相关蛋白1（RAD 51 AP 1）是同源重组（HR）DNA修复途径中的关键蛋白。RAD 51 AP 1的缺失导致HR缺陷、基因组不稳定和端粒侵蚀。RAD 51 AP 1与RAD 51重组酶物理相互作用，并促进RAD 51介导的供体DNA捕获，突触复合物组装和置换环形成时，用无核小体的DNA底物进行测试。然而，在细胞中，DNA被包装成染色质，对HR反应的复杂性构成了额外的障碍。在这项研究中，我们表明，RAD 51 AP 1结合到核小体核心颗粒（NCPs），染色质的最小基本单位，其中大约两个超螺旋圈的147 bp的双链DNA被包裹在一个组蛋白八聚体周围，没有游离的DNA末端。我们确定了一个C-末端区域的RAD 51 AP 1，包括其先前映射的DNA结合域，作为关键的调解之间的关联RAD 51 AP 1和NCP和组蛋白八聚体。使用HR活性的体外替代测定，我们表明RAD 51 AP 1能够促进双链DNA捕获并分别启动与NCP和染色质化模板DNA的联合分子形成。总之，我们的研究结果表明，RAD 51 AP 1直接协助RAD 51介导的染色质中供体DNA的搜索。我们提出了一个模型，其中RAD 51 AP 1锚定的DNA模板通过其核小体的亲和力RAD 51-ssDNA核蛋白丝。
RAD51-associated protein 1 (RAD51AP1) is a key protein in the homologous recombination (HR) DNA repair pathway. Loss of RAD51AP1 leads to defective HR, genome instability, and telomere erosion. RAD51AP1 physically interacts with the RAD51 recombinase and promotes RAD51-mediated capture of donor DNA, synaptic complex assembly, and displacement-loop formation when tested with nucleosome-free DNA substrates. In cells, however, DNA is packaged into chromatin, posing an additional barrier to the complexities of the HR reaction. In this study, we show that RAD51AP1 binds to nucleosome core particles (NCPs), the minimum basic unit of chromatin in which approximately two superhelical turns of 147 bp double-stranded DNA are wrapped around one histone octamer with no free DNA ends remaining. We identified a C-terminal region in RAD51AP1, including its previously mapped DNA-binding domain, as critical for mediating the association between RAD51AP1 and both the NCP and the histone octamer. Using in vitro surrogate assays of HR activity, we show that RAD51AP1 is capable of promoting duplex DNA capture and initiating joint-molecule formation with the NCP and chromatinized template DNA, respectively. Together, our results suggest that RAD51AP1 directly assists in the RAD51-mediated search for donor DNA in chromatin. We present a model, in which RAD51AP1 anchors the DNA template through affinity for its nucleosomes to the RAD51-ssDNA nucleoprotein filament.
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DOI：
10.1038/nsb901
发表时间：
2003-03-01
期刊：
NATURE STRUCTURAL BIOLOGY
影响因子：
--
作者：
Alexeev, A;Mazin, A;Kowalczykowski, SC
通讯作者：
Kowalczykowski, SC
影响因子：
5.6
作者：
Lowary, PT;Widom, J
通讯作者：
Widom, J
影响因子：
4.6
作者：
Kobayashi W;Takaku M;Machida S;Tachiwana H;Maehara K;Ohkawa Y;Kurumizaka H
通讯作者：
Kurumizaka H
影响因子：
14.9
作者：
Kovalenko, OV;Golub, EI;Radding, CM
通讯作者：
Radding, CM
影响因子：
2.9
作者：
Gottesfeld, JM;Luger, K
通讯作者：
Luger, K