Mechanical design principles of a mitotic spindle

  1. Jonathan J Ward
  2. Helio Roque
  3. Claude Antony
  4. Francois J Nedelec  Is a corresponding author
  1. European Molecular Biology Laboratory, Germany
  2. University of Oxford, United Kingdom
  3. Institut Génétique Biologie Moléculaire Cellulaire, France

Abstract

An organised spindle is crucial to the fidelity of chromosome segregation, but the relationship between spindle structure and function is not well understood in any cell type. The anaphase B spindle in fission yeast has a slender morphology and must elongate against compressive forces. This 'pushing' mode of chromosome transport renders the spindle susceptible to breakage, as observed in cells with a variety of defects. Here we perform electron tomographic analyses of the spindle, which suggest that it organises a limited supply of structural components to increase its compressive strength. Structural integrity is maintained throughout the spindle's four-fold elongation by organising microtubules into a rigid transverse array, preserving correct microtubule number and dynamically rescaling microtubule length.

Article and author information

Author details

  1. Jonathan J Ward

    Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany
    Competing interests
    The authors declare that no competing interests exist.
  2. Helio Roque

    Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  3. Claude Antony

    Department of Integrated Structural Biology, UMR7104, Institut Génétique Biologie Moléculaire Cellulaire, Illkirch, France
    Competing interests
    The authors declare that no competing interests exist.
  4. Francois J Nedelec

    Cell Biology and Biophysics, European Molecular Biology Laboratory, Heidelberg, Germany
    For correspondence
    nedelec@embl.de
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Frank Jülicher, Max Planck Institute for the Physics of Complex Systems, Germany

Version history

  1. Received: May 16, 2014
  2. Accepted: December 17, 2014
  3. Accepted Manuscript published: December 18, 2014 (version 1)
  4. Version of Record published: January 14, 2015 (version 2)

Copyright

© 2014, Ward 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. Jonathan J Ward
  2. Helio Roque
  3. Claude Antony
  4. Francois J Nedelec
(2014)
Mechanical design principles of a mitotic spindle
eLife 3:e03398.
https://doi.org/10.7554/eLife.03398

Share this article

https://doi.org/10.7554/eLife.03398

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