1. Cell Biology
  2. Plant Biology
Download icon

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
Research Article
  • Cited 43
  • Views 4,578
  • Annotations
Cite this article as: eLife 2015;4:e05868 doi: 10.7554/eLife.05868

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.

Metrics

  • 4,578
    Page views
  • 1,214
    Downloads
  • 43
    Citations

Article citation count generated by polling the highest count across the following sources: Crossref, Scopus, PubMed Central.

Download links

A two-part list of links to download the article, or parts of the article, in various formats.

Downloads (link to download the article as PDF)

Download citations (links to download the citations from this article in formats compatible with various reference manager tools)

Open citations (links to open the citations from this article in various online reference manager services)

Categories and tags

Research organism

Further reading

    1. Biochemistry and Chemical Biology
    2. Cell Biology

    Complementary biosensors reveal different G-protein signaling modes triggered by GPCRs and non-receptor activators

    Mikel Garcia-Marcos
    Research Article Updated

    It has become evident that activation of heterotrimeric G-proteins by cytoplasmic proteins that are not G-protein-coupled receptors (GPCRs) plays a role in physiology and disease. Despite sharing the same biochemical guanine nucleotide exchange factor (GEF) activity as GPCRs in vitro, the mechanisms by which these cytoplasmic proteins trigger G-protein-dependent signaling in cells have not been elucidated. Heterotrimeric G-proteins can give rise to two active signaling species, Gα-GTP and dissociated Gβγ, with different downstream effectors, but how non-receptor GEFs affect the levels of these two species in cells is not known. Here, a systematic comparison of GPCRs and three unrelated non-receptor proteins with GEF activity in vitro (GIV/Girdin, AGS1/Dexras1, and Ric-8A) revealed high divergence in their contribution to generating Gα-GTP and free Gβγ in cells directly measured with live-cell biosensors. These findings demonstrate fundamental differences in how receptor and non-receptor G-protein activators promote signaling in cells despite sharing similar biochemical activities in vitro.

    1. Cell Biology
    2. Developmental Biology

    The recycling endosome protein Rab25 coordinates collective cell movements in the zebrafish surface epithelium

    Patrick Morley Willoughby et al.
    Research Article Updated

    In emerging epithelial tissues, cells undergo dramatic rearrangements to promote tissue shape changes. Dividing cells remain interconnected via transient cytokinetic bridges. Bridges are cleaved during abscission and currently, the consequences of disrupting abscission in developing epithelia are not well understood. We show that the Rab GTPase Rab25 localizes near cytokinetic midbodies and likely coordinates abscission through endomembrane trafficking in the epithelium of the zebrafish gastrula during epiboly. In maternal-zygotic Rab25a and Rab25b mutant embryos, morphogenic activity tears open persistent apical cytokinetic bridges that failed to undergo timely abscission. Cytokinesis defects result in anisotropic cell morphologies that are associated with a reduction of contractile actomyosin networks. This slows cell rearrangements and alters the viscoelastic responses of the tissue, all of which likely contribute to delayed epiboly. We present a model in which Rab25 trafficking coordinates cytokinetic bridge abscission and cortical actin density, impacting local cell shape changes and tissue-scale forces.

    1. Cell Biology
    2. Computational and Systems Biology

    Artistoo, a library to build, share, and explore simulations of cells and tissues in the web browser

    Inge M N Wortel, Johannes Textor
    Tools and Resources

    The Cellular Potts Model (CPM) is a powerful in silico method for simulating biological processes at tissue scale. Their inherently graphical nature makes CPMs very accessible in theory, but in practice, they are mostly implemented in specialised frameworks users need to master before they can run simulations. We here present Artistoo (Artificial Tissue Toolbox), a JavaScript library for building 'explorable' CPM simulations where viewers can change parameters interactively, exploring their effects in real time. Simulations run directly in the web browser and do not require third-party software, plugins, or back-end servers. The JavaScript implementation imposes no major performance loss compared to frameworks written in C++; Artistoo remains sufficiently fast for interactive, real time simulations. Artistoo provides an opportunity to unlock CPM models for a broader audience: Interactive simulations can be shared via a URL in a zero-install setting. We discuss applications in CPM research, science dissemination, open science, and education.