Interdependent progression of bidirectional sister replisomes in E. coli

• Published in: eLife Vol. 12
• Main Authors: Chen, Po Jui, McMullin, Anna B, Visser, Bryan J, Mei, Qian, Rosenberg, Susan M, Bates, David
• Format: Journal Article
• Language: English
• Published: England eLife Sciences Publications Ltd 09-01-2023; eLife Sciences Publications, Ltd
• Subjects: Bacteria; Cell cycle; Chromosomes; Chromosomes - metabolism; DNA; DNA biosynthesis; DNA Replication; DNA-Binding Proteins - metabolism; E coli; Escherichia coli - genetics; Escherichia coli - metabolism; Factories; Flow cytometry; Genetics and Genomics; Microbiology and Infectious Disease; Microscopy; Proteins; Replication; replication factory; replication fork progression; replication fork stalling; replisome dynamics; replisome localization; Structure-function relationships; Transcription factors; replication fork stalling; genetics; replisome dynamics; infectious disease; microbiology; replication factory; genomics; replisome localization; E. coli; replication fork progression
• ISSN: 2050-084X; 2050-084X
• DOI: 10.7554/eLife.82241

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
, 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.