CTP and parS coordinate ParB partition complex dynamics and ParA-ATPase activation for ParABS-mediated DNA partitioning

  1. James A Taylor
  2. Yeonee Seol
  3. Jagat Budhathoki
  4. Keir C Neuman
  5. Kiyoshi Mizuuchi  Is a corresponding author
  1. University of Oxford, United Kingdom
  2. National Heart, Lung and Blood Institute, National Institutes of Health, United States
  3. NIDDK/NIH, United States
  4. National Institutes of Health, United States

Abstract

ParABS partition systems, comprising the centromere-like DNA sequence parS, the parS-binding ParB-CTPase and the nucleoid-binding ParA-ATPase, ensure faithful segregation of bacterial chromosomes and low-copy-number plasmids. F-plasmid partition complexes containing ParBF and parSF move by generating and following a local concentration gradient of nucleoid-bound ParAF. However, the process through which ParBF activates ParAF-ATPase has not been defined. We studied CTP- and parSF-modulated ParAF-ParBF complex assembly, in which DNA-bound ParAF-ATP dimers are activated for ATP hydrolysis by interacting with two ParBF N-terminal domains. CTP or parSF enhances the ATPase rate without significantly accelerating ParAF-ParBF complex assembly. Together, parSF and CTP accelerate ParAF-ParBF assembly without further significant increase in ATPase rate. Magnetic-tweezers experiments showed that CTP promotes multiple ParBF loading onto parSF-containing DNA, generating condensed partition complex-like assemblies. We propose that ParBF in the partition complex adopts a conformation that enhances ParBF-ParBF and ParAF-ParBF interactions promoting efficient partitioning.

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All data generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided for all relevant figures.

Article and author information

Author details

  1. James A Taylor

    Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  2. Yeonee Seol

    Laboratory of Single Molecule Biophysics, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Jagat Budhathoki

    NIDDK/NIH, Bethesda, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Keir C Neuman

    National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-0863-5671
  5. Kiyoshi Mizuuchi

    NIDDK/NIH, Bethesda, United States
    For correspondence
    kiyoshimi@niddk.nih.gov
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-8193-9244

Funding

NIDDK/NIH (Intramural Research Fund)

  • Kiyoshi Mizuuchi

NHLBI/NIH (Intramural Research Fund)

  • Keir C Neuman

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

Copyright

This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.

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  1. James A Taylor
  2. Yeonee Seol
  3. Jagat Budhathoki
  4. Keir C Neuman
  5. Kiyoshi Mizuuchi
(2021)
CTP and parS coordinate ParB partition complex dynamics and ParA-ATPase activation for ParABS-mediated DNA partitioning
eLife 10:e65651.
https://doi.org/10.7554/eLife.65651

Share this article

https://doi.org/10.7554/eLife.65651

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