1. Structural Biology and Molecular Biophysics
  2. Cell Biology
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Bipolar filaments of human nonmuscle myosin 2-A and 2-B have distinct motile and mechanical properties

  1. Luca Melli  Is a corresponding author
  2. Neil Billington
  3. Sara A Sun
  4. Jonathan E Bird
  5. Attila Nagy
  6. Thomas B Friedman
  7. Yasuharu Takagi
  8. James R Sellers  Is a corresponding author
  1. National Heart, Lung and Blood Institute, National Institutes of Health, United States
  2. National Institute on Deafness and Other Communication Disorders, National Institutes of Health, United States
  3. National Institutes of Allergy and Infectious Diseases, National Institutes of Health, United States
Research Article
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Cite this article as: eLife 2018;7:e32871 doi: 10.7554/eLife.32871

Abstract

Nonmuscle myosin 2 (NM-2) powers cell motility and tissue morphogenesis by assembling into bipolar filaments that interact with actin. Although the enzymatic properties of purified NM-2 motor fragments have been determined, the emergent properties of filament ensembles are unknown. Using single myosin filament in vitro motility assays, we report fundamental differences in filaments formed of different NM-2 motors. Filaments consisting of NM2-B moved processively along actin, while under identical conditions, NM2-A filaments did not. By more closely mimicking the physiological milieu, either by increasing solution viscosity or by co-polymerization with NM2-B, NM2-A containing filaments moved processively. Our data demonstrate that both the kinetic and mechanical properties of these two myosins, in addition to the stochiometry of NM-2 subunits, can tune filament mechanical output. We propose altering NM-2 filament composition is a general cellular strategy for tailoring force production of filaments to specific functions such as maintaining tension or remodeling actin.

Article and author information

Author details

  1. Luca Melli

    Cell Biology and Physiology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, United States
    For correspondence
    luca.melli@nih.gov
    Competing interests
    The authors declare that no competing interests exist.
  2. Neil Billington

    Cell Biology and Physiology Center, 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:" 0000-0003-2306-0228
  3. Sara A Sun

    Cell Biology and Physiology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Jonathan E Bird

    Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, 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:" 0000-0001-5531-8794
  5. Attila Nagy

    Vaccine Production Program Laboratory, National Institutes of Allergy and Infectious Diseases, National Institutes of Health, Gaithersburg, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Thomas B Friedman

    Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, United States
    Competing interests
    The authors declare that no competing interests exist.
  7. Yasuharu Takagi

    Cell Biology and Physiology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, United States
    Competing interests
    The authors declare that no competing interests exist.
  8. James R Sellers

    Cell Biology and Physiology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, United States
    For correspondence
    sellersj@nhlbi.nih.gov
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-6296-564X

Funding

National Heart, Lung, and Blood Institute (HL001786)

  • Jonathan E Bird
  • Attila Nagy

National Institute on Deafness and Other Communication Disorders (DC000039)

  • Thomas B Friedman

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

Reviewing Editor

  1. Mohan K Balasubramanian, University of Warwick, United Kingdom

Publication history

  1. Received: October 17, 2017
  2. Accepted: January 22, 2018
  3. Accepted Manuscript published: February 8, 2018 (version 1)
  4. Version of Record published: February 28, 2018 (version 2)

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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