Interdependent progression of bidirectional sister replisomes in E. coli.
Interdependent progression of bidirectional sister replisomes in E. coli.
复制标题
DOI：
10.7554/elife.82241
复制
发表时间：
2023-01-09
期刊：
影响因子：
7.7
通讯作者：
Bates, David
中科院分区：
文献类型：
--
作者：
Chen, Po Jui;McMullin, Anna B.;Visser, Bryan J.;Mei, Qian;Rosenberg, Susan M.;Bates, David
关键词：
从同一起点开始的双向DNA复制复合物在其部分或全部寿命中保持共定位在工厂配置中。然而，几乎没有证据表明姐妹复制体在功能上是相互依赖的，工厂复制的后果也是未知的。在这里，我们研究了大肠杆菌中的姐妹复制体之间的功能关系，大肠杆菌在同一个复制周期中自然地表现出工厂和孤立的配置。使用诱导型转录因子路障系统，我们发现阻断一个复制体会导致姐妹复制体的整体进展和速度显着下降。值得注意的是，只有当阻断发生时，姐妹复制体仍处于工厂配置中时，进展才会受损-当姐妹复制体物理上分离时，阻断一个分支对另一个复制体没有显著影响。工厂复制的中断也导致了fork停顿和fork重启机制需求的增加。这些结果表明，姐妹复制体之间的物理关联是重要的，建立一个有效的和不间断的复制程序。我们讨论了我们的研究结果对复制工厂的结构和功能的机制，以及复制有问题的DNA，如高度转录的片段的细胞策略的影响。
Bidirectional DNA replication complexes initiated from the same origin remain colocalized in a factory configuration for part or all their lifetimes. However, there is little evidence that sister replisomes are functionally interdependent, and the consequence of factory replication is unknown. Here, we investigated the functional relationship between sister replisomes in Escherichia coli, which naturally exhibits both factory and solitary configurations in the same replication cycle. Using an inducible transcription factor roadblocking system, we found that blocking one replisome caused a significant decrease in overall progression and velocity of the sister replisome. Remarkably, progression was impaired only if the block occurred while sister replisomes were still in a factory configuration – blocking one fork had no significant effect on the other replisome when sister replisomes were physically separate. Disruption of factory replication also led to increased fork stalling and requirement of fork restart mechanisms. These results suggest that physical association between sister replisomes is important for establishing an efficient and uninterrupted replication program. We discuss the implications of our findings on mechanisms of replication factory structure and function, and cellular strategies of replicating problematic DNA such as highly transcribed segments.