1. Cell Biology

The equatorial position of the metaphase plate ensures symmetric cell divisions

  1. Chia Huei Tan
  2. Ivana Gasic
  3. Sabina P Huber-Reggi
  4. Damian Dudka
  5. Marin Barisic
  6. Helder Maiato
  7. Patrick Meraldi  Is a corresponding author
  1. University of Geneva, Switzerland
  2. ETH Zurich, Switzerland
  3. Universidade do Porto, Portugal
https://doi.org/10.7554/eLife.05124
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Cite this article
  1. Chia Huei Tan
  2. Ivana Gasic
  3. Sabina P Huber-Reggi
  4. Damian Dudka
  5. Marin Barisic
  6. Helder Maiato
  7. Patrick Meraldi
(2015)
The equatorial position of the metaphase plate ensures symmetric cell divisions
eLife 4:e05124.
https://doi.org/10.7554/eLife.05124
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Abstract

Chromosome alignment in the middle of the bipolar spindle is a hallmark of metazoan cell divisions. When we offset the metaphase plate position by creating an asymmetric centriole distribution on each pole, we find that metaphase plates relocate to the middle of the spindle before anaphase. The spindle assembly checkpoint enables this centering mechanism by providing cells enough time to correct metaphase plate position. The checkpoint responds to unstable kinetochore-microtubule attachments resulting from an imbalance in microtubule stability between the two half-spindles in cells with an asymmetric centriole distribution. Inactivation of the checkpoint prior to metaphase plate centering leads to asymmetric cell divisions and daughter cells of unequal size; in contrast, if the checkpoint is inactivated after the metaphase plate has centered its position, symmetric cell divisions ensue. This indicates that the equatorial position of the metaphase plate is essential for symmetric cell divisions.

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Author details

  1. Chia Huei Tan

    Department of Physiology and Metabolism, Medical Faculty, University of Geneva, Geneva, Switzerland
    Competing interests
    The authors declare that no competing interests exist.

  2. Ivana Gasic

    Department of Physiology and Metabolism, Medical Faculty, University of Geneva, Geneva, Switzerland
    Competing interests
    The authors declare that no competing interests exist.

  3. Sabina P Huber-Reggi

    Institute of Biochemistry, ETH Zurich, Zurich, Switzerland
    Competing interests
    The authors declare that no competing interests exist.

  4. Damian Dudka

    Department of Physiology and Metabolism, Medical Faculty, University of Geneva, Geneva, Switzerland
    Competing interests
    The authors declare that no competing interests exist.

  5. Marin Barisic

    Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
    Competing interests
    The authors declare that no competing interests exist.

  6. Helder Maiato

    Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
    Competing interests
    The authors declare that no competing interests exist.

  7. Patrick Meraldi

    Department of Physiology and Metabolism, Medical Faculty, University of Geneva, Geneva, Switzerland
    For correspondence
    Patrick.meraldi@unige.ch
    Competing interests
    The authors declare that no competing interests exist.

Copyright

© 2015, Huei Tan 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. Chia Huei Tan
  2. Ivana Gasic
  3. Sabina P Huber-Reggi
  4. Damian Dudka
  5. Marin Barisic
  6. Helder Maiato
  7. Patrick Meraldi
(2015)
The equatorial position of the metaphase plate ensures symmetric cell divisions
eLife 4:e05124.
https://doi.org/10.7554/eLife.05124

Share this article

https://doi.org/10.7554/eLife.05124

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