Transcription leads to pervasive replisome instability in bacteria

  1. Sarah Mangiameli
  2. Christopher N Merrikh
  3. Paul A Wiggins  Is a corresponding author
  4. Houra Merrikh  Is a corresponding author
  1. University of Washington, United States
  2. University of Washington Medical Center, United States

Abstract

The canonical model of DNA replication describes a highly-processive and largely continuous process by which the genome is duplicated. This continuous model is based upon in vitro reconstitution and in vivo ensemble experiments. Here, we characterize the replisome-complex stoichiometry and dynamics with single-molecule resolution in bacterial cells. Strikingly, the stoichiometries of the replicative helicase, DNA polymerase, and clamp loader complexes are consistent with the presence of only one active replisome in a significant fraction of cells (>40%). Furthermore, many of the observed complexes have short lifetimes (<8 minutes), suggesting that replisome disassembly is quite prevalent, possibly occurring several times per cell cycle. The instability of the replisome complex is conflict-induced: transcription inhibition stabilizes these complexes, restoring the second replisome in many of the cells. Our results suggest that, in contrast to the canonical model, DNA replication is a largely discontinuous process in vivo due to pervasive replication-transcription conflicts.

Article and author information

Author details

  1. Sarah Mangiameli

    Department of Physics, University of Washington, Seattle, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Christopher N Merrikh

    Department of Microbiology, University of Washington, Seattle, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Paul A Wiggins

    Department of Physics, University of Washington, Seattle, United States
    For correspondence
    pwiggins@uw.edu
    Competing interests
    The authors declare that no competing interests exist.
  4. Houra Merrikh

    Department of Microbiology, University of Washington Medical Center, Seattle, United States
    For correspondence
    merrikh@uw.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-9956-9640

Funding

National Science Foundation (MCB1243492.)

  • Sarah Mangiameli
  • Christopher N Merrikh
  • Paul A Wiggins
  • Houra Merrikh

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Antoine M van Oijen, University of Wollongong, Australia

Publication history

  1. Received: July 20, 2016
  2. Accepted: January 15, 2017
  3. Accepted Manuscript published: January 16, 2017 (version 1)
  4. Version of Record published: February 13, 2017 (version 2)
  5. Version of Record updated: March 1, 2017 (version 3)

Copyright

© 2017, Mangiameli 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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  1. Sarah Mangiameli
  2. Christopher N Merrikh
  3. Paul A Wiggins
  4. Houra Merrikh
(2017)
Transcription leads to pervasive replisome instability in bacteria
eLife 6:e19848.
https://doi.org/10.7554/eLife.19848

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