Identification of the Xenopus DNA2 protein as a major nuclease for the 5'->3' strand-specific processing of DNA ends.
Identification of the Xenopus DNA2 protein as a major nuclease for the 5'->3' strand-specific processing of DNA ends.
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将爪蟾DNA2蛋白鉴定为DNA末端5' - > 3'链特异性加工的主要核酸酶。
DOI：
10.1093/nar/gkn616
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发表时间：
2008-11
影响因子：
14.9
通讯作者：
Yan, Hong
中科院分区：
文献类型：
--
作者：
Liao, Shuren;Toczylowski, Thomas;Yan, Hong
同源依赖的DNA双链断裂(DSB)修复的第一步是DNA末端的5‘链特异性处理，以产生3’单链尾巴。尽管进行了广泛的努力，但直接负责真核细胞5‘链切除的核酸酶(S)仍然难以捉摸。以非洲爪哇卵的核质提取物为模型系统，我们发现DNA的加工至少包括两个步骤：依赖于三磷酸腺苷的末端解离和三磷酸腺苷不依赖的单链尾巴的5‘→3’降解。解离步骤是由DNA解旋酶催化的，其中主要的解旋酶之一是非洲爪哇综合征蛋白(XWRN)，它是RecQ解旋酶家族的成员。在这项研究中，我们报道了非洲爪哇DNA 2(XDNA2)的纯化和鉴定，它是导致单链尾巴5‘→3’降解的核酸酶之一。XDNA2的免疫耗尽导致末端加工和同源依赖的DSB修复显著减少。这些结果提供了强有力的证据，证明在真核生物中，xDNA2是切除DNA末端以进行同源依赖的DSB修复的主要核酸酶。
The first step of homology-dependent DNA double-strand break (DSB) repair is the 5′ strand-specific processing of DNA ends to generate 3′ single-strand tails. Despite extensive effort, the nuclease(s) that is directly responsible for the resection of 5′ strands in eukaryotic cells remains elusive. Using nucleoplasmic extracts (NPE) derived from the eggs of Xenopus laevis as the model system, we have found that DNA processing consists of at least two steps: an ATP-dependent unwinding of ends and an ATP-independent 5′→3′ degradation of single-strand tails. The unwinding step is catalyzed by DNA helicases, the major one of which is the Xenopus Werner syndrome protein (xWRN), a member of the RecQ helicase family. In this study, we report the purification and identification of the Xenopus DNA2 (xDNA2) as one of the nucleases responsible for the 5′→3′ degradation of single-strand tails. Immunodepletion of xDNA2 resulted in a significant reduction in end processing and homology-dependent DSB repair. These results provide strong evidence that xDNA2 is a major nuclease for the resection of DNA ends for homology-dependent DSB repair in eukaryotes.
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影响因子：
16
作者：
Lengsfeld, Bettina M.;Rattray, Alison J.;Paull, Tanya T.
通讯作者：
Paull, Tanya T.
影响因子：
4.5
作者：
Budd ME;Tong AH;Polaczek P;Peng X;Boone C;Campbell JL
通讯作者：
Campbell JL
DOI：
10.1073/pnas.1431624100
发表时间：
2003-07-08
影响因子：
11.1
作者：
Imamura, O;Campbell, JL
通讯作者：
Campbell, JL
影响因子：
4.8
作者：
Clerici, M;Mantiero, D;Longhese, MP
通讯作者：
Longhese, MP
影响因子：
64.8
作者：
Bae, SH;Bae, KH;Seo, YS
通讯作者：
Seo, YS