RecQ family members combine strand pairing and unwinding activities to catalyze strand exchange
RecQ family members combine strand pairing and unwinding activities to catalyze strand exchange
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DOI：
10.1074/jbc.m414130200
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发表时间：
2005-06-17
影响因子：
4.8
通讯作者：
Orren, DK
中科院分区：
文献类型：
--
作者：
Machwe, A;Xiao, LR;Orren, DK
RecQ解旋酶对于维持基因组完整性至关重要。在这项研究中，我们表明，三个RecQ成员（WRN，缺乏沃纳综合征; BLM，缺乏布卢姆综合征;和果蝇RecQ 5 b（dmRecQ 5 b））具有新的链配对活动。此外，这些酶中的每一种都将这种链配对活性与其固有的DNA解旋能力相结合，以进行协调的链交换。在这方面，WRN和BLM比dmRecQ 5 b有效得多，显然是因为dmRecQ 5 b缺乏有助于DNA结合、链配对和链交换的解旋酶结构域C-末端的保守序列。基于我们的研究结果，我们假设，某些RecQ解旋酶的结构设计，以完成复杂的复制和重组中间体的链交换。这与RecQ成员在DNA代谢中的作用以及与RecQ缺陷相关的非法重组和癌症易感表型高度一致。
RecQ helicases are critical for maintaining genomic integrity. In this study, we show that three RecQ members (WRN, deficient in the Werner syndrome; BLM, deficient in the Bloom syndrome; and Drosophila melanogaster RecQ5b (dmRecQ5b)) possess a novel strand pairing activity. Furthermore, each of these enzymes combines this strand pairing activity with its inherent DNA unwinding capability to perform coordinated strand exchange. In this regard, WRN and BLM are considerably more efficient than dmRecQ5b, apparently because dmRecQ5b lacks conserved sequences C-terminal to the helicase domain that contribute to DNA binding, strand pairing, and strand exchange. Based on our findings, we postulate that certain RecQ helicases are structurally designed to accomplish strand exchange on complex replication and recombination intermediates. This is highly consistent with proposed roles for RecQ members in DNA metabolism and the illegitimate recombination and cancer-prone phenotypes associated with RecQ defects.