1. Chromosomes and Gene Expression
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MukB ATPases are regulated independently by the N- and C-terminal domains of MukF kleisin

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Cite this article as: eLife 2018;7:e31522 doi: 10.7554/eLife.31522

Abstract

The Escherichia coli SMC complex, MukBEF, acts in chromosome segregation. MukBEF shares the distinctive architecture of other SMC complexes, with one prominent difference; unlike other kleisins, MukF forms dimers through its N-terminal domain. We show that a 4-helix bundle adjacent to the MukF dimerization domain interacts functionally with the MukB coiled-coiled 'neck' adjacent to the ATPase head. We propose that this interaction leads to an asymmetric tripartite complex, as in other SMC complexes. Since MukF dimerization is preserved during this interaction, MukF directs the formation of dimer of dimer MukBEF complexes, observed previously in vivo. The MukF N- and C-terminal domains stimulate MukB ATPase independently and additively. We demonstrate that impairment of the MukF interaction with MukB in vivo leads to ATP hydrolysis-dependent release of MukBEF complexes from chromosomes.

Article and author information

Author details

  1. Katarzyna Zawadzka

    Department of Biochemistry, University of Oxford, Oxford, United Kingdom
    Competing interests
    No competing interests declared.
  2. Pawel Zawadzki

    Department of Biochemistry, University of Oxford, Oxford, United Kingdom
    Competing interests
    No competing interests declared.
  3. Rachel Baker

    Department of Biochemistry, University of Oxford, Oxford, United Kingdom
    Competing interests
    No competing interests declared.
  4. Karthik V Rajasekar

    Department of Biochemistry, University of Oxford, Oxford, United Kingdom
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-8146-6560
  5. Florence Wagner

    Department of Biochemistry, University of Oxford, Oxford, United Kingdom
    Competing interests
    No competing interests declared.
  6. David J Sherratt

    Department of Biochemistry, University of Oxford, Oxford, United Kingdom
    For correspondence
    david.sherratt@bioch.ox.ac.uk
    Competing interests
    David J Sherratt, Reviewing editor, eLife.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2104-5430
  7. Lidia K Arciszewska

    Department of Biochemistry, University of Oxford, Oxford, United Kingdom
    For correspondence
    lidia.arciszewska@bioch.ox.ac.uk
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-0252-4874

Funding

Wellcome (Senior Investigator Award)

  • David J Sherratt

Leverhulme Trust (RP2013-K-017)

  • David J Sherratt

National Science Centre, Poland (2015/19/P/NZ1/03859)

  • Pawel Zawadzki

Foundation for Polish Science (First TEAM/2016-1/9)

  • Pawel Zawadzki

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

Reviewing Editor

  1. Andrea Musacchio, Max Planck Institute of Molecular Physiology, Germany

Publication history

  1. Received: August 24, 2017
  2. Accepted: January 10, 2018
  3. Accepted Manuscript published: January 11, 2018 (version 1)
  4. Version of Record published: February 14, 2018 (version 2)

Copyright

© 2018, Zawadzka 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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