The role of APETALA1 in petal number robustness

  1. Marie Monniaux
  2. Bjorn Pieper
  3. Sarah M McKim
  4. Anne-Lise Routier-Kierzkowska
  5. Daniel Kierzkowski
  6. Richard S Smith
  7. Angela Hay  Is a corresponding author
  1. Max Planck Institute for Plant Breeding Research, Germany
  2. University of Oxford, United Kingdom

Abstract

Invariant floral forms are important for reproductive success and robust to natural perturbations. Petal number, for example, is invariant in Arabidopsis thaliana flowers. However, petal number varies in the closely related species Cardamine hirsuta, and the genetic basis for this difference between species is unknown. Here we show that divergence in the pleiotropic floral regulator APETALA1 (AP1) can account for the species-specific difference in petal number robustness. This large effect of AP1 is explained by epistatic interactions: A. thaliana AP1 confers robustness by masking the phenotypic expression of quantitative trait loci controlling petal number in C. hirsuta. We show that C. hirsuta AP1 fails to complement this function of A. thaliana AP1, conferring variable petal number, and that upstream regulatory regions of AP1 contribute to this divergence. Moreover, variable petal number is maintained in C. hirsuta despite sufficient standing genetic variation in natural accessions to produce plants with four-petalled flowers.

Data availability

All data generated or analysed during this study are included in the manuscript and supporting files.

Article and author information

Author details

  1. Marie Monniaux

    Department of Comparative Development and Genetics, Max Planck Institute for Plant Breeding Research, Cologne, Germany
    Competing interests
    The authors declare that no competing interests exist.
  2. Bjorn Pieper

    Department of Comparative Development and Genetics, Max Planck Institute for Plant Breeding Research, Cologne, Germany
    Competing interests
    The authors declare that no competing interests exist.
  3. Sarah M McKim

    Plant Sciences Department, University of Oxford, Oxford, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  4. Anne-Lise Routier-Kierzkowska

    Department of Comparative Development and Genetics, Max Planck Institute for Plant Breeding Research, Cologne, Germany
    Competing interests
    The authors declare that no competing interests exist.
  5. Daniel Kierzkowski

    Department of Comparative Development and Genetics, Max Planck Institute for Plant Breeding Research, Cologne, Germany
    Competing interests
    The authors declare that no competing interests exist.
  6. Richard S Smith

    Department of Comparative Development and Genetics, Max Planck Institute for Plant Breeding Research, Cologne, Germany
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-9220-0787
  7. Angela Hay

    Department of Comparative Development and Genetics, Max Planck Institute for Plant Breeding Research, Cologne, Germany
    For correspondence
    hay@mpipz.mpg.de
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4609-5490

Funding

Biotechnology and Biological Sciences Research Council (BB/H01313X/1)

  • Angela Hay

Human Frontier Science Program (RGP0008/2013)

  • Richard S Smith

Royal Society (University Research Fellowship)

  • Angela Hay

Max Planck Society (W2 Minerva Fellowship)

  • Angela Hay

European Molecular Biology Organization (Long Term Fellowship)

  • Marie Monniaux

National Science and Engineering Research Council of Canada (Post-Doctoral Fellowship)

  • Sarah M McKim

European Molecular Biology Organization (Long Term Fellowship)

  • Sarah M McKim

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

Reviewing Editor

  1. Sheila McCormick, University of California-Berkeley, United States

Version history

  1. Received: June 23, 2018
  2. Accepted: October 11, 2018
  3. Accepted Manuscript published: October 18, 2018 (version 1)
  4. Version of Record published: October 29, 2018 (version 2)

Copyright

© 2018, Monniaux 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. Marie Monniaux
  2. Bjorn Pieper
  3. Sarah M McKim
  4. Anne-Lise Routier-Kierzkowska
  5. Daniel Kierzkowski
  6. Richard S Smith
  7. Angela Hay
(2018)
The role of APETALA1 in petal number robustness
eLife 7:e39399.
https://doi.org/10.7554/eLife.39399

Share this article

https://doi.org/10.7554/eLife.39399

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