Localization of an accessory helicase at the replisome is critical in sustaining efficient genome duplication.
Localization of an accessory helicase at the replisome is critical in sustaining efficient genome duplication.
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DOI：
10.1093/nar/gkq889
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发表时间：
2011-02
影响因子：
14.9
通讯作者：
McGlynn P
中科院分区：
文献类型：
--
作者：
Atkinson J;Gupta MK;Rudolph CJ;Bell H;Lloyd RG;McGlynn P
基因组复制需要辅助解旋酶在复制叉前进之前取代蛋白质。大肠杆菌含有Rep、UvrD和DinG三种解旋酶，它们可能促进蛋白结合DNA的复制。这些解旋酶之一Rep也与复制解旋酶DnaB相互作用。我们证明，Rep是唯一假定的辅助解旋酶，其缺席的结果在增加染色体复制时间。我们还表明，Rep和DnaB之间的相互作用是Rep维持快速基因组复制所必需的。此外，这种Rep-DnaB相互作用在最小化对阻断的复制叉的重组加工和复制体重组的需要方面是至关重要的，这表明Rep和DnaB的共定位最小化了复制叉的停滞和随后的失活。这些数据表明，E.大肠杆菌中只含有一个解旋酶，它在野生型细胞中的分叉处充当辅助马达，这种活性对于维持快速基因组复制至关重要，并且与复制体的共定位对于这种功能至关重要。鉴于唯一的其他特征的辅助电机，酿酒酵母Rrm 3 p，与复制体物理关联，我们的演示功能的重要性，这样的协会表明，共定位可能是一个保守的功能辅助复制电机。
Genome duplication requires accessory helicases to displace proteins ahead of advancing replication forks. Escherichia coli contains three helicases, Rep, UvrD and DinG, that might promote replication of protein-bound DNA. One of these helicases, Rep, also interacts with the replicative helicase DnaB. We demonstrate that Rep is the only putative accessory helicase whose absence results in an increased chromosome duplication time. We show also that the interaction between Rep and DnaB is required for Rep to maintain rapid genome duplication. Furthermore, this Rep–DnaB interaction is critical in minimizing the need for both recombinational processing of blocked replication forks and replisome reassembly, indicating that colocalization of Rep and DnaB minimizes stalling and subsequent inactivation of replication forks. These data indicate that E. coli contains only one helicase that acts as an accessory motor at the fork in wild-type cells, that such an activity is critical for the maintenance of rapid genome duplication and that colocalization with the replisome is crucial for this function. Given that the only other characterized accessory motor, Saccharomyces cerevisiae Rrm3p, associates physically with the replisome, our demonstration of the functional importance of such an association indicates that colocalization may be a conserved feature of accessory replicative motors.
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影响因子：
16
作者：
Ivessa, AS;Lenzmeier, BA;Zakian, VA
通讯作者：
Zakian, VA
影响因子：
3.6
作者：
Baharoglu Z;Lestini R;Duigou S;Michel B
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作者：
Guy, Colin P.;Atkinson, John;Gupta, Milind K.;Mahdi, Akeel A.;Gwynn, Emma J.;Rudolph, Christian J.;Moon, Peter B.;van Knippenberg, Ingeborg C.;Cadman, Chris J.;Dillingham, Mark S.;Lloyd, Robert G.;McGlynn, Peter
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McGlynn, Peter
影响因子：
10.5
作者：
Azvolinsky, Anna;Dunaway, Stephen;Zakian, Virginia A.
通讯作者：
Zakian, Virginia A.
影响因子：
6.8
作者：
GORBALENYA, AE;KOONIN, EV
通讯作者：
KOONIN, EV