Dynamic F-actin movement is essential for fertilization in Arabidopsis thaliana

  1. Tomokazu Kawashima
  2. Daisuke Maruyama
  3. Murat Shagirov
  4. Jing Li
  5. Yuki Hamamura
  6. Ramesh Yelagandula
  7. Yusuke Toyama
  8. Frédéric Berger  Is a corresponding author
  1. Gregor Mendel Institute, Austria
  2. Nagoya University, Japan
  3. National University of Singapore, Singapore
  4. Nagoya University Graduate School of Science, Japan
  5. National Univeristy of Singapore, Singapore

Abstract

In animals, microtubules and centrosomes direct the migration of gamete pronuclei for fertilization. By contrast, flowering plants have lost essential components of the centrosome, raising the question of how flowering plants control gamete nuclei migration during fertilization. Here, we use Arabidopsis thaliana to document a novel mechanism that regulates F-actin dynamics in the female gametes and is essential for fertilization. Live imaging shows that F-actin structures assist the male nucleus during its migration towards the female nucleus. We identify a female gamete-specific Rho-GTPase that regulates F-actin dynamics, and further show that actin-myosin interactions are also involved in male gamete nucleus migration. Genetic analyses and imaging indicate that microtubules are dispensable for migration and fusion of male and female gamete nuclei. The innovation of a novel actin-based mechanism of fertilization during plant evolution might account for the complete loss of the centrosome in flowering plants.

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Author details

  1. Tomokazu Kawashima

    Gregor Mendel Institute, Vienna, Austria
    Competing interests
    The authors declare that no competing interests exist.
  2. Daisuke Maruyama

    Nagoya University, Nagoya, Japan
    Competing interests
    The authors declare that no competing interests exist.
  3. Murat Shagirov

    National University of Singapore, Singapore, Singapore
    Competing interests
    The authors declare that no competing interests exist.
  4. Jing Li

    Gregor Mendel Institute, Vienna, Austria
    Competing interests
    The authors declare that no competing interests exist.
  5. Yuki Hamamura

    Nagoya University Graduate School of Science, Nagoya, Japan
    Competing interests
    The authors declare that no competing interests exist.
  6. Ramesh Yelagandula

    Gregor Mendel Institute, Vienna, Austria
    Competing interests
    The authors declare that no competing interests exist.
  7. Yusuke Toyama

    National University of Singapore, Singapore, Singapore
    Competing interests
    The authors declare that no competing interests exist.
  8. Frédéric Berger

    National Univeristy of Singapore, Singapore, Singapore
    For correspondence
    fred@tll.org.sg
    Competing interests
    The authors declare that no competing interests exist.

Copyright

© 2014, Kawashima 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. Tomokazu Kawashima
  2. Daisuke Maruyama
  3. Murat Shagirov
  4. Jing Li
  5. Yuki Hamamura
  6. Ramesh Yelagandula
  7. Yusuke Toyama
  8. Frédéric Berger
(2014)
Dynamic F-actin movement is essential for fertilization in Arabidopsis thaliana
eLife 3:e04501.
https://doi.org/10.7554/eLife.04501

Share this article

https://doi.org/10.7554/eLife.04501

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