Interdependent progression of bidirectional sister replisomes in E. coli
- Baylor College of Medicine, United States
- Rice University, United States
Abstract
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 E. 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.
Data availability
Sequencing data generated in this study have been deposited in the National Center for Biotechnology (NCBI) Sequence Read Archive (SRA), BioProject PRJNA860928.
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Interdependent progression of bidirectional sister replisomes in E. coliNCBI Sequence Read Archive BioProject PRJNA860928.
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Association of nucleoid proteins with coding and non-coding segments of the Escherichia coli genomeNucleic Acids Research Supplementary Data.
Article and author information
Author details
Funding
National Institutes of Health (R01 GM102679)
- David Bates
National Institutes of Health (R01 GM135368)
- David Bates
National Institutes of Health (R35 GM122598)
- Susan M Rosenberg
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2023, Chen et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Interdependent progression of bidirectional sister replisomes in E. coli
eLife 12:e82241.
https://doi.org/10.7554/eLife.82241
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