Nanoscale architecture of the Schizosaccharomyces pombe contractile ring

  1. Nathan A McDonald
  2. Abigail L Lind
  3. Sarah E Smith
  4. Rong Li
  5. Kathleen Gould  Is a corresponding author
  1. Vanderbilt University, United States
  2. Vanderbilt University Medical Center, United States
  3. Stowers Institute for Medical Research, United States
  4. Johns Hopkins University School of Medicine, United States

Abstract

The contractile ring is a complex molecular apparatus important for dividing many eukaryotic cells. Despite knowledge of its composition, the molecular architecture of the ring is not known. Here we applied super-resolution microscopy and FRET to determine the nanoscale spatial organization of Schizosaccharomyces pombe contractile ring components relative to the plasma membrane. As in other membrane-tethered actin structures, contractile ring proteins are stratified relative to the membrane. The lowest layer (0-80 nm) contains membrane-binding scaffolds, formin, and the myosin-II tail. An intermediate zone (80-160 nm) consists of a network of cytokinesis accessory proteins and signaling components that influence cell division. Most interior from the membrane (160-400 nm) is F-actin, myosin motor domains, and an F-actin crosslinker. Circumferentially within the ring, multiple proximal membrane proteins form different sized clusters, while components farther from the membrane are uniformly distributed. This comprehensive organizational map provides a framework for understanding contractile ring function.

Article and author information

Author details

  1. Nathan A McDonald

    Department of Cell and Developmental Biology, Vanderbilt University, Nashville, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2716-3881
  2. Abigail L Lind

    Department of Biomedical Informatics, Vanderbilt University Medical Center, Nashville, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Sarah E Smith

    Stowers Institute for Medical Research, Kansas City, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Rong Li

    Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-0540-6566
  5. Kathleen Gould

    Department of Cell and Developmental Biology, Vanderbilt University, Nashville, United States
    For correspondence
    kathy.gould@vanderbilt.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3810-4070

Funding

National Institutes of Health (Research grant)

  • Kathleen Gould

American Heart Association (Graduate Student Fellowship)

  • Nathan A McDonald

National Institutes of Health (Research grant)

  • Rong Li

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: May 22, 2017
  2. Accepted: September 14, 2017
  3. Accepted Manuscript published: September 15, 2017 (version 1)
  4. Version of Record published: September 26, 2017 (version 2)

Copyright

© 2017, McDonald 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. Nathan A McDonald
  2. Abigail L Lind
  3. Sarah E Smith
  4. Rong Li
  5. Kathleen Gould
(2017)
Nanoscale architecture of the Schizosaccharomyces pombe contractile ring
eLife 6:e28865.
https://doi.org/10.7554/eLife.28865

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