Auxin regulates SNARE-dependent vacuolar morphology restricting cell size

  1. Christian Löfke
  2. Kai Dünser
  3. David Scheuring
  4. Jürgen Kleine-Vehn  Is a corresponding author
  1. University of Natural Resources and Life Sciences, Austria

Abstract

The control of cellular growth is central to multicellular patterning. In plants, the encapsulating cell wall literally binds neighbouring cells to each other and limits cellular sliding/migration. In contrast to its developmental importance, growth regulation is poorly understood in plants. Here we reveal that the phytohormone auxin impacts on the shape of the biggest plant organelle, the vacuole. TIR1/AFBs-dependent auxin signalling posttranslationally controls the protein abundance of vacuolar SNARE components. Genetic and pharmacological interference with the auxin effect on vacuolar SNAREs interrelates with auxin-resistant vacuolar morphogenesis and cell size regulation. Vacuolar SNARE VTI11 is strictly required for auxin-reliant vacuolar morphogenesis and loss of function renders cells largely insensitive to auxin-dependent growth inhibition. Our data suggests that the adaptation of SNARE-dependent vacuolar morphogenesis allows auxin to limit cellular expansion, contributing to root organ growth rates.

Article and author information

Author details

  1. Christian Löfke

    Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna, Austria
    Competing interests
    The authors declare that no competing interests exist.
  2. Kai Dünser

    Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna, Austria
    Competing interests
    The authors declare that no competing interests exist.
  3. David Scheuring

    Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna, Austria
    Competing interests
    The authors declare that no competing interests exist.
  4. Jürgen Kleine-Vehn

    Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna, Austria
    For correspondence
    juergen.kleine-vehn@boku.ac.at
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Christian S Hardtke, University of Lausanne, Switzerland

Publication history

  1. Received: December 3, 2014
  2. Accepted: March 5, 2015
  3. Accepted Manuscript published: March 5, 2015 (version 1)
  4. Version of Record published: April 2, 2015 (version 2)

Copyright

© 2015, Löfke 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. Christian Löfke
  2. Kai Dünser
  3. David Scheuring
  4. Jürgen Kleine-Vehn
(2015)
Auxin regulates SNARE-dependent vacuolar morphology restricting cell size
eLife 4:e05868.
https://doi.org/10.7554/eLife.05868

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