1. Developmental Biology
  2. Plant Biology
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Three ancient hormonal cues co-ordinate shoot branching in a moss

  1. Yoan Coudert
  2. Wojtek Palubicki
  3. Karin Ljung
  4. Ondrej Novak
  5. Ottoline Leyser
  6. C Jill Harrison  Is a corresponding author
  1. University of Cambridge, United Kingdom
  2. Umeå University, Sweden
  3. Palacký University and Institute of Experimental Botany ASCR, Czech Republic
Research Article
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Cite this article as: eLife 2015;4:e06808 doi: 10.7554/eLife.06808

Abstract

Shoot branching is a primary contributor to plant architecture, evolving independently in flowering plant sporophytes and moss gametophytes. Mechanistic understanding of branching is largely limited to flowering plants such as Arabidopsis, which have a recent evolutionary origin. We show that in gametophytic shoots of Physcomitrella, lateral branches arise by re-specification of epidermal cells into branch initials. A simple model co-ordinating the activity of leafy shoot tips can account for branching patterns, and three known and ancient hormonal regulators of sporophytic branching interact to generate the branching pattern- auxin, cytokinin and strigolactone. The mode of auxin transport required in branch patterning is a key divergence point from known sporophytic pathways. Although PIN-mediated basipetal auxin transport regulates branching patterns in flowering plants, this is not so in Physcomitrella, where bi-directional transport is required to generate realistic branching patterns. Experiments with callose synthesis inhibitors suggest plasmodesmal connectivity as a potential mechanism for transport.

Article and author information

Author details

  1. Yoan Coudert

    Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  2. Wojtek Palubicki

    Sainsbury Laboratory, University of Cambridge, Cambridge, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  3. Karin Ljung

    Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Umeå University, Umeå, Sweden
    Competing interests
    The authors declare that no competing interests exist.
  4. Ondrej Novak

    Laboratory of Growth Regulators, Centre of the Region Haná for Biotechnological and Agricultural Research, Palacký University and Institute of Experimental Botany ASCR, Olomouc, Czech Republic
    Competing interests
    The authors declare that no competing interests exist.
  5. Ottoline Leyser

    Sainsbury Laboratory, University of Cambridge, Cambridge, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  6. C Jill Harrison

    Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
    For correspondence
    cjh97@cam.ac.uk
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Christian S Hardtke, University of Lausanne, Switzerland

Publication history

  1. Received: February 5, 2015
  2. Accepted: March 10, 2015
  3. Accepted Manuscript published: March 25, 2015 (version 1)
  4. Version of Record published: April 9, 2015 (version 2)

Copyright

© 2015, Coudert 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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