Active suppression of a leaf meristem orchestrates determinate leaf growth

Abstract

Leaves are flat determinate organs derived from indeterminate shoot apical meristems. The presence of a specific leaf meristem is debated, as anatomical features typical of meristems are not present in leaves. Here we demonstrate that multiple NGATHA (NGA) and CINCINNATA-class-TCP (CIN-TCP) transcription factors act redundantly, shortly after leaf initiation, to gradually restrict the activity of a leaf meristem in Arabidopsis thaliana to marginal and basal domains, and that their absence confers persistent marginal growth to leaves, cotyledons and floral organs. The marginal restriction of the broadly acting leaf meristem following primordia initiation, is mediated by the juxtaposition of adaxial and abaxial domains and maintained by WOX homeobox transcription factors, whereas other marginal elaboration genes are dispensable for its maintenance. This genetic framework parallels the morphogenetic program of shoot apical meristems and may represent a relic of an ancestral shoot system from which seed plant leaves evolved.

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Article and author information

Author details

  1. John Paul Alvarez

    School of Biological Sciences, Monash University, Melbourne, Australia
    Competing interests
    The authors declare that no competing interests exist.
  2. Chihiro Furumizu

    School of Biological Sciences, Monash University, Melbourne, Australia
    Competing interests
    The authors declare that no competing interests exist.
  3. Idan Efroni

    School of Biological Sciences, Monash University, Melbourne, Australia
    Competing interests
    The authors declare that no competing interests exist.
  4. Yuval Eshed

    School of Biological Sciences, Monash University, Melbourne, Australia
    Competing interests
    The authors declare that no competing interests exist.
  5. John L Bowman

    School of Biological Sciences, Monash University, Melbourne, Australia
    For correspondence
    John.Bowman@monash.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-7347-3691

Funding

Australian Research Council (DP110100070, DP130100177, DP160100892)

  • John Paul Alvarez
  • Chihiro Furumizu
  • John L Bowman

Israel Science Foundation (863-06)

  • John Paul Alvarez
  • Yuval Eshed

European Molecular Biology Organization (185-2010)

  • Idan Efroni

United States - Israel Binational Agricultural Research and Development Fund (3767-05)

  • John Paul Alvarez
  • Yuval Eshed
  • John L Bowman

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Richard Amasino, University of Wisconsin, United States

Version history

  1. Received: February 5, 2016
  2. Accepted: September 30, 2016
  3. Accepted Manuscript published: October 6, 2016 (version 1)
  4. Accepted Manuscript updated: October 11, 2016 (version 2)
  5. Version of Record published: November 4, 2016 (version 3)

Copyright

© 2016, Alvarez 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. John Paul Alvarez
  2. Chihiro Furumizu
  3. Idan Efroni
  4. Yuval Eshed
  5. John L Bowman
(2016)
Active suppression of a leaf meristem orchestrates determinate leaf growth
eLife 5:e15023.
https://doi.org/10.7554/eLife.15023

Share this article

https://doi.org/10.7554/eLife.15023

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