Chromosomal over-replication in Escherichia coli recG cells is triggered by replication fork fusion and amplified if replichore symmetry is disturbed.
Chromosomal over-replication in Escherichia coli recG cells is triggered by replication fork fusion and amplified if replichore symmetry is disturbed.
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DOI：
10.1093/nar/gky566
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发表时间：
2018-09-06
影响因子：
14.9
通讯作者：
Rudolph CJ
中科院分区：
文献类型：
--
作者：
Midgley-Smith SL;Dimude JU;Taylor T;Forrester NM;Upton AL;Lloyd RG;Rudolph CJ
染色体复制是通过在确定的起始处组装复制叉来启动的。叉子朝相反的方向前进，直到它们与汇聚的叉子融合。最近的工作强调，在亲核细胞和真核细胞中，分叉融合都是高度编排的。环状大肠杆菌染色体从单一来源(ORIC)复制，单叉融合发生在ORIC对面的特殊终止区，该区域建立了一个由TER序列结合的TUS蛋白介导的分叉陷阱，允许分叉进入但不能离开。在这里，我们进一步定义了分叉融合的分子细节以及RecG解旋酶在复制终止中的作用。我们的数据支持这样的观点，即分叉融合有可能引发已经复制的DNA的本地重新复制。在ΔRecG细胞中，这种潜力在相当一部分细胞中实现，当一个叉子在汇聚的叉子到达之前被困住一段时间时，这种潜力会显着提高。他们还支持这样的观点，即终止区进化到包含这种过度复制，我们认为在TER/TUS复合体上复制叉子的稳定阻止是限制复制终止时出现问题的可能性的一个重要特征。
Chromosome duplication initiates via the assembly of replication forks at defined origins. Forks proceed in opposite directions until they fuse with a converging fork. Recent work highlights that fork fusions are highly choreographed both in pro- and eukaryotic cells. The circular Escherichia coli chromosome is replicated from a single origin (oriC), and a single fork fusion takes place in a specialised termination area opposite oriC that establishes a fork trap mediated by Tus protein bound at ter sequences that allows forks to enter but not leave. Here we further define the molecular details of fork fusions and the role of RecG helicase in replication termination. Our data support the idea that fork fusions have the potential to trigger local re-replication of the already replicated DNA. In ΔrecG cells this potential is realised in a substantial fraction of cells and is dramatically elevated when one fork is trapped for some time before the converging fork arrives. They also support the idea that the termination area evolved to contain such over-replication and we propose that the stable arrest of replication forks at ter/Tus complexes is an important feature that limits the likelihood of problems arising as replication terminates.
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影响因子：
4.5
作者：
Azeroglu B;Mawer JS;Cockram CA;White MA;Hasan AM;Filatenkova M;Leach DR
通讯作者：
Leach DR
影响因子：
3.5
作者：
Dimude JU;Midgley-Smith SL;Stein M;Rudolph CJ
通讯作者：
Rudolph CJ
影响因子：
4.5
作者：
De Septenville, Anne L.;Duigou, Stephane;Michel, Benedicte
通讯作者：
Michel, Benedicte
DOI：
10.1073/pnas.84.7.1754
发表时间：
1987-04-01
影响因子：
11.1
作者：
HILL, TM;HENSON, JM;KUEMPEL, PL
通讯作者：
KUEMPEL, PL
DOI：
10.1073/pnas.111008998
发表时间：
2001-07-17
影响因子：
11.1
作者：
Barre, FX;Soballe, B;Sherratt, D
通讯作者：
Sherratt, D