Specific polar subpopulations of astral microtubules control spindle orientation and symmetric neural stem cell division

  1. Felipe Mora-Bermúdez
  2. Fumio Matsuzaki
  3. Wieland B Huttner  Is a corresponding author
  1. Max Planck Institute of Molecular Cell Biology and Genetics, Germany
  2. RIKEN Center for Developmental Biology, Japan

Abstract

Mitotic spindle orientation is crucial for symmetric vs. asymmetric cell division and depends on astral microtubules. Here, we show that distinct subpopulations of astral microtubules exist, which have differential functions in regulating spindle orientation and division symmetry. Specifically, in polarized stem cells of developing mouse neocortex, astral microtubules reaching the apical and basal cell cortex, but not those reaching the central cell cortex, are more abundant in symmetrically than asymmetrically dividing cells and reduce spindle orientation variability. This promotes symmetric divisions by maintaining an apico-basal cleavage plane. The greater abundance of apical/basal astrals depends on a higher concentration, at the basal cell cortex, of LGN, a known spindle-cell cortex linker. Furthermore, newly developed specific microtubule perturbations that selectively decrease apical/basal astrals recapitulate the symmetric-to-asymmetric division switch and suffice to increase neurogenesis, in vivo. Thus, our study identifies a novel link between cell polarity, astral microtubules and spindle orientation in morphogenesis.

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Author details

  1. Felipe Mora-Bermúdez

    Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
    Competing interests
    The authors declare that no competing interests exist.
  2. Fumio Matsuzaki

    RIKEN Center for Developmental Biology, Kobe, Japan
    Competing interests
    The authors declare that no competing interests exist.
  3. Wieland B Huttner

    Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
    For correspondence
    huttner@mpi-cbg.de
    Competing interests
    The authors declare that no competing interests exist.

Ethics

Animal experimentation: All animal studies were conducted in accordance with German animal welfare legislation, and the necessary licenses obtained from the regional Ethical Commission for Animal Experimentation of Dresden, Germany.

Copyright

© 2014, Mora-Bermúdez 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. Felipe Mora-Bermúdez
  2. Fumio Matsuzaki
  3. Wieland B Huttner
(2014)
Specific polar subpopulations of astral microtubules control spindle orientation and symmetric neural stem cell division
eLife 3:e02875.
https://doi.org/10.7554/eLife.02875

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https://doi.org/10.7554/eLife.02875

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