Cho Endonuclease Functions during DNA Interstrand Cross-Link Repair in Escherichia coli.
Cho Endonuclease Functions during DNA Interstrand Cross-Link Repair in Escherichia coli.
复制标题
Cho 核酸内切酶在大肠杆菌 DNA 链间交联修复过程中发挥作用。
DOI：
10.1128/jb.00509-16
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发表时间：
2016
影响因子：
3.2
通讯作者：
Courcelle,Justin
中科院分区：
文献类型：
--
作者：
Perera,AnthonigeVidya;Mendenhall,JamesBrian;Courcelle,CharmainTan;Courcelle,Justin
DNA 链间交联是将双链 DNA 的两条链共价连接的复杂损伤。建议通过 UvrABC 核苷酸切除修复复合物启动病变去除；然而，人们对这一复杂修复途径的后续步骤知之甚少。在这项研究中，我们描述了核苷酸切除修复突变体在补骨脂素诱导损伤的情况下对生存的贡献。出乎意料的是，我们观察到核苷酸切除修复突变体对补骨脂素诱导的损伤表现出不同的敏感性，其中uvrC突变体的敏感性低于uvrA或uvrB。我们发现 Cho，一种替代性核酸内切酶，与 UvrAB 一起作用，并负责降低 uvrC 突变体的超敏反应。我们发现Cho对生存的贡献与DNA链间交联的存在相关，而不是单加合物，并且在补骨脂素DNA加合物从基因组的整体修复过程中在初始切口之后或独立于初始切口起作用。重要性DNA链间交联是与双链DNA的两条链共价结合的复杂损伤，其修复机制仍然知之甚少。在这项研究中，我们证明 Cho（一种替代核酸内切酶）与 UvrAB 作用，参与光激活补骨脂素存在下形成的 DNA 链间交联的修复。 Cho 对生存的贡献与 DNA 链间交联的存在相关，并且在修复过程中的初始切口之后或独立于初始切口进行操作。
DNA interstrand cross-links are complex lesions that covalently link both strands of the duplex DNA. Lesion removal is proposed to be initiated via the UvrABC nucleotide excision repair complex; however, less is known about the subsequent steps of this complex repair pathway. In this study, we characterized the contribution of nucleotide excision repair mutants to survival in the presence of psoralen-induced damage. Unexpectedly, we observed that the nucleotide excision repair mutants exhibit differential sensitivity to psoralen-induced damage, withuvrCmutants being less sensitive than eitheruvrAoruvrB. We show that Cho, an alternative endonuclease, acts with UvrAB and is responsible for the reduced hypersensitivity ofuvrCmutants. We find that Cho's contribution to survival correlates with the presence of DNA interstrand cross-links, rather than monoadducts, and operates at a step after, or independently from, the initial incision during the global repair of psoralen DNA adducts from the genome.IMPORTANCEDNA interstrand cross-links are complex lesions that covalently bind to both strands of the duplex DNA and whose mechanism of repair remains poorly understood. In this study, we show that Cho, an alternative endonuclease, acts with UvrAB and participates in the repair of DNA interstrand cross-links formed in the presence of photoactivated psoralens. Cho's contribution to survival correlates with the presence of DNA interstrand cross-links and operates at a step after, or independently from, the initial incision during the repair process.