Location of Repository

Modularity of the Bacterial Cell Cycle Enables Independent Spatial and Temporal Control of DNA Replication

By Kristina Jonas, Y. Erin Chen and Michael T. LaubY. Erin Chen and Michael T. Laub

Abstract

Background: Complex regulatory circuits in biology are often built of simpler subcircuits or modules. In most cases, the functional consequences and evolutionary origins of modularity remain poorly defined. Results: Here, by combining single-cell microscopy with genetic approaches, we demonstrate that two separable modules independently govern the temporal and spatial control of DNA replication in the asymmetrically dividing bacterium Caulobacter crescentus. DNA replication control involves DnaA, which promotes initiation, and CtrA, which silences initiation. We show that oscillations in DnaA activity dictate the periodicity of replication while CtrA governs the asymmetric replicative fates of daughter cells. Importantly, we demonstrate that DnaA activity oscillates independently of CtrA. Conclusions: The genetic separability of spatial and temporal control modules in Caulobacter reflects their evolutionary history. DnaA is the central component of an ancient and phylogenetically widespread circuit that governs replication periodicity in Caulobacter and most other bacteria. By contrast, CtrA, which is found only in the asymmetrically dividing α-proteobacteria, was integrated later in evolution to enforce replicative asymmetry on daughter cells.National Institutes of Health (U.S.) (Grant 5R01GM082899

Publisher: Elsevier
Year: 2011
DOI identifier: 10.1016/j.cub.2011.05.040
OAI identifier: oai:dspace.mit.edu:1721.1/84668
Provided by: DSpace@MIT
Journal:
Download PDF:
Sorry, we are unable to provide the full text but you may find it at the following location(s):
  • http://hdl.handle.net/1721.1/8... (external link)
  • http://dx.doi.org/10.1016/j.cu... (external link)
  • https://orcid.org/0000-0002-82... (external link)
  • http://purl.org/eprint/type/Jo... (external link)
  • Suggested articles


    To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.