The circadian clock ensures successful DNA replication in cyanobacteria

Disruption of circadian rhythms causes decreased health and fitness, and evidence from multiple organisms links clock disruption to dysregulation of the cell cycle. However, the function of circadian regulation for the essential process of DNA replication remains elusive. Here, we demonstrate that i...

Full description

Saved in:
Bibliographic Details
Published in:Proceedings of the National Academy of Sciences - PNAS 2021-05, Vol.118 (20), p.1-8
Main Authors: Liao, Yi, Rust, Michael J.
Format: Article
Language:English
Subjects:
Bacterial Proteins - genetics
Bacterial Proteins - metabolism
Biological clocks
Biological Sciences
Cell cycle
Cell Cycle - genetics
Chromosomes
Circadian Clocks - genetics
Circadian rhythm
Circadian Rhythm - genetics
Circadian rhythms
Computer Simulation
Cyanobacteria
Deoxyribonucleic acid
Disruption
DNA
DNA biosynthesis
DNA Replication
Gene Expression Regulation, Bacterial
Genomes
Mathematical models
Metabolism
Misalignment
Models, Statistical
Night
Photoperiod
Replication
Replication forks
Synechococcus - genetics
Synechococcus - growth & development
Synechococcus - metabolism
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Disruption of circadian rhythms causes decreased health and fitness, and evidence from multiple organisms links clock disruption to dysregulation of the cell cycle. However, the function of circadian regulation for the essential process of DNA replication remains elusive. Here, we demonstrate that in the cyanobacterium Synechococcus elongatus, a model organism with the simplest known circadian oscillator, the clock generates rhythms in DNA replication to minimize the number of open replication forks near dusk that would have to complete after sunset. Metabolic rhythms generated by the clock ensure that resources are available early at night to support any remaining replication forks. Combining mathematical modeling and experiments, we show that metabolic defects caused by clock–environment misalignment result in premature replisome disassembly and replicative abortion in the dark, leaving cells with incomplete chromosomes that persist through the night. Our study thus demonstrates that a major function of this ancient clock in cyanobacteria is to ensure successful completion of genome replication in a cycling environment.
ISSN:0027-8424
1091-6490
DOI:10.1073/pnas.2022516118