The mesh is a network of microtubule connectors that stabilizes individual kinetochore fibers of the mitotic spindle

  1. Faye M Nixon
  2. Cristina Gutiérrez-Caballero
  3. Fiona E Hood
  4. Daniel G Booth
  5. Ian A Prior
  6. Stephen J Royle  Is a corresponding author
  1. Warwick Medical School, United Kingdom
  2. University of Liverpool, United Kingdom
  3. University of Edinburgh, United Kingdom

Abstract

Kinetochore fibers (K-fibers) of the mitotic spindle are force-generating units that power chromosome movement during mitosis. K-fibers are composed of many microtubules that are held together throughout their length. Here we show, using 3D electron microscopy, that K-fiber microtubules are connected by a network of microtubule connectors. We term this network 'the mesh'. The K-fiber mesh is made of linked multipolar connectors. Each connector has up to four struts, so that a single connector can link up to four microtubules. Molecular manipulation of the mesh by overexpression of TACC3 causes disorganization of the K-fiber microtubules. Optimal stabilization of K-fibers by the mesh is required for normal progression through mitosis. We propose that the mesh stabilizes K-fibers by pulling MTs together and thereby maintaining the integrity of the fiber. Our work thus identifies the K-fiber meshwork of linked multipolar connectors as a key integrator and determinant of K-fiber structure and function.

Article and author information

Author details

  1. Faye M Nixon

    Division of Biomedical Cell Biology, Warwick Medical School, Coventry, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  2. Cristina Gutiérrez-Caballero

    Division of Biomedical Cell Biology, Warwick Medical School, Coventry, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  3. Fiona E Hood

    Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Liverpool, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  4. Daniel G Booth

    Wellcome Trust Centre for Cell Biolog, University of Edinburgh, Edinburgh, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  5. Ian A Prior

    Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Liverpool, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  6. Stephen J Royle

    Division of Biomedical Cell Biology, Warwick Medical School, Coventry, United Kingdom
    For correspondence
    s.j.royle@warwick.ac.uk
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Anna Akhmanova, Utrecht University, Netherlands

Version history

  1. Received: March 20, 2015
  2. Accepted: June 18, 2015
  3. Accepted Manuscript published: June 19, 2015 (version 1)
  4. Version of Record published: July 9, 2015 (version 2)

Copyright

© 2015, Nixon 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. Faye M Nixon
  2. Cristina Gutiérrez-Caballero
  3. Fiona E Hood
  4. Daniel G Booth
  5. Ian A Prior
  6. Stephen J Royle
(2015)
The mesh is a network of microtubule connectors that stabilizes individual kinetochore fibers of the mitotic spindle
eLife 4:e07635.
https://doi.org/10.7554/eLife.07635

Share this article

https://doi.org/10.7554/eLife.07635

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