Cell elongation is regulated through a central circuit of interacting transcription factors in the Arabidopsis hypocotyl

  1. Eunkyoo Oh
  2. Jia-Ying Zhu
  3. Ming-Yi Bai
  4. Rafael A Arenhart
  5. Yu Sun
  6. Zhi-Yong Wang  Is a corresponding author
  1. Carnegie Institution for Science, United States

Abstract

As the major mechanism of plant growth and morphogenesis, cell elongation is controlled by many hormonal and environmental signals. How these signals are coordinated at the molecular level to ensure coherent cellular responses remains unclear. Here, we illustrate a molecular circuit that integrates all major growth-regulating signals, including auxin, brassinosteroid, gibberellin, light, and temperature. Analyses of genome-wide targets, genetic and biochemical interactions demonstrate that the auxin-response factor ARF6, the light/temperature-regulated transcription factor PIF4, and the brassinosteroid-signaling transcription factor BZR1, interact with each other and cooperatively regulate large numbers of common target genes, but their DNA-binding activities are blocked by the gibberellin-inactivated repressor RGA. In addition, a tripartite HLH/bHLH module feedback-regulates PIFs and additional bHLH factors that interact with ARF6, and thereby modulates auxin sensitivity according to developmental and environmental cues. Our results demonstrate a central growth-regulation circuit that integrates hormonal, environmental, and developmental controls of cell elongation in Arabidopsis hypocotyl.

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Author details

  1. Eunkyoo Oh

    Carnegie Institution for Science, Stanford, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Jia-Ying Zhu

    Carnegie Institution for Science, Stanford, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Ming-Yi Bai

    Carnegie Institution for Science, Stanford, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Rafael A Arenhart

    Carnegie Institution for Science, Stanford, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Yu Sun

    Carnegie Institution for Science, Stanford, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Zhi-Yong Wang

    Carnegie Institution for Science, Stanford, United States
    For correspondence
    zywang24@stanford.edu
    Competing interests
    The authors declare that no competing interests exist.

Copyright

© 2014, Oh 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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https://doi.org/10.7554/eLife.03031

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