Structural basis for transcription-coupled repair: The N terminus of Mfd resembles UvrB with degenerate ATPase motifs
Structural basis for transcription-coupled repair: The N terminus of Mfd resembles UvrB with degenerate ATPase motifs
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DOI：
10.1016/j.jmb.2005.10.033
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发表时间：
2006-01-27
影响因子：
5.6
通讯作者：
Hopfner, KP
中科院分区：
文献类型：
--
作者：
Assenmacher, N;Wenig, K;Hopfner, KP
转录修复偶联因子Mfd从DNA损伤中去除停滞的RNA聚合酶，并将转录与原核生物中的UVrABC依赖性核苷酸切除修复联系起来。我们报告了大肠杆菌Mfd（Mfd-N）的UvrA结合N末端（残基1-333）的2.1埃晶体结构。值得注意的是，Mfd-N揭示了一个类似于修复酶UvrB的三个N-末端结构域的折叠。Mfd的结构域1A采用典型的RecA折叠，结构域1B匹配UvrB的损伤结合结构域，结构域2高度类似于UvrB的牵连UvrA结合结构域。然而，Mfd显然缺乏一个功能性的ATP结合位点，不包含UvrB的DNA损伤结合基序。因此，我们的研究结果表明，Mfd可能会形成一个UvrA招募因子在停滞的转录复合物，结构上，但不催化类似UvrB。(c)2005爱思唯尔有限公司保留所有权利。
The transcription repair coupling factor Mfd removes stalled RNA polymerase from DNA lesions and links transcription to UvrABC-dependent nucleotide excision repair in prokaryotes. We report the 2.1 angstrom crystal structure of the UvrA-binding N terminus (residues 1-333) of Escherichia coli Mfd (Mfd-N). Remarkably, Mfd-N reveals a fold that resembles the three N-terminal domains of the repair enzyme UvrB. Domain 1A of Mfd adopts a typical RecA fold, domain 1B matches the damage-binding domain of the UvrB, and domain 2 highly resembles the implicated UvrA-binding domain of UvrB. However, Mfd apparently lacks a functional ATP-binding site and does not contain the DNA damage-binding motifs of UvrB. Thus, our results suggest that Mfd might form a UvrA recruitment factor at stalled transcription complexes that architecturally but not catalytically resembles UvrB. (c) 2005 Elsevier Ltd. All rights reserved.