Shade-induced nuclear localization of PIF7 is regulated by phosphorylation and 14-3-3 proteins in Arabidopsis

Abstract

Shade avoidance syndrome enables shaded plants to grow and compete effectively against their neighbors. In Arabidopsis, the shade-induced de-phosphorylation of the transcription factor PIF7 (PHYTOCHROME-INTERACTING FACTOR 7) is the key event linking light perception to stem elongation. However, the mechanism through which phosphorylation regulates the activity of PIF7 is unclear. Here, we show that shade light induces the de-phosphorylation and nuclear accumulation of PIF7. Phosphorylation-resistant site mutations in PIF7 result in increased nuclear localization and shade-induced gene expression, and consequently augment hypocotyl elongation. PIF7 interacts with 14-3-3 proteins. Blocking the interaction between PIF7 and 14-3-3 proteins or reducing the expression of 14-3-3 proteins accelerates shade-induced nuclear localization and de-phosphorylation of PIF7, and enhances the shade phenotype. By contrast, the 14-3-3 overexpressing line displays an attenuated shade phenotype. These studies demonstrate a phosphorylation-dependent translocation of PIF7 when plants are in shade and a novel mechanism involving 14-3-3 proteins, mediated by the retention of PIF7 in the cytoplasm that suppresses the shade response.

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. Xu Huang

    State Key Laboratory of Genetic Engineering and Institute of Plant Biology, School of Life Sciences, Fudan University, Shanghai, China
    Competing interests
    The authors declare that no competing interests exist.
  2. Qian Zhang

    State Key Laboratory of Genetic Engineering and Institute of Plant Biology, School of Life Sciences, Fudan University, Shanghai, China
    Competing interests
    The authors declare that no competing interests exist.
  3. Yupei Jiang

    State Key Laboratory of Genetic Engineering and Institute of Plant Biology, School of Life Sciences, Fudan University, Shanghai, China
    Competing interests
    The authors declare that no competing interests exist.
  4. Chuanwei Yang

    State Key Laboratory of Genetic Engineering and Institute of Plant Biology, School of Life Sciences, Fudan University, Shanghai, China
    Competing interests
    The authors declare that no competing interests exist.
  5. Qianyue Wang

    State Key Laboratory of Genetic Engineering and Institute of Plant Biology, School of Life Sciences, Fudan University, Shanghai, China
    Competing interests
    The authors declare that no competing interests exist.
  6. Lin Li

    State Key Laboratory of Genetic Engineering and Institute of Plant Biology, School of Life Sciences, Fudan University, Shanghai, China
    For correspondence
    linli@fudan.edu.cn
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4840-5245

Funding

National Natural Science Foundation of China (31470374)

  • Lin Li

National Natural Science Foundation of China (31500973)

  • Lin Li

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

Reviewing Editor

  1. Zhi-Yong Wang, Carnegie Institution for Science, United States

Version history

  1. Received: August 30, 2017
  2. Accepted: April 11, 2018
  3. Accepted Manuscript published: June 21, 2018 (version 1)
  4. Version of Record published: July 9, 2018 (version 2)
  5. Version of Record updated: July 31, 2018 (version 3)

Copyright

© 2018, Huang 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. Xu Huang
  2. Qian Zhang
  3. Yupei Jiang
  4. Chuanwei Yang
  5. Qianyue Wang
  6. Lin Li
(2018)
Shade-induced nuclear localization of PIF7 is regulated by phosphorylation and 14-3-3 proteins in Arabidopsis
eLife 7:e31636.
https://doi.org/10.7554/eLife.31636

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