Arabidopsis formin 2 regulates cell-to-cell trafficking by capping and stabilizing actin filaments at plasmodesmata

  1. Min Diao
  2. Sulin Ren
  3. Qiannan Wang
  4. Lichao Qian
  5. Jiangfeng Shen
  6. Yule Liu
  7. Shanjin Huang  Is a corresponding author
  1. Tsinghua University, China
  2. Chinese Academy of Sciences, China

Abstract

Here, we demonstrate that Arabidopsis thaliana Formin 2 (AtFH2) localizes to PD through its transmembrane domain and is required for normal intercellular trafficking. Although loss-of-function atfh2 mutants have no overt developmental defect, PD's permeability and sensitivity to virus infection are increased in atfh2 plants. Interestingly, AtFH2 functions in a partially redundant manner with its closest homolog AtFH1, which also contains a PD localization signal. Strikingly, targeting of Class I formins to PD was also confirmed in rice, suggesting that the involvement of Class I formins in regulating actin dynamics at PD may be evolutionarily conserved in plants. In vitro biochemical analysis showed that AtFH2 fails to nucleate actin assembly but caps and stabilizes actin filaments. We also demonstrate that the interaction between AtFH2 and actin filaments is crucial for its function in vivo. These data allow us to propose that AtFH2 regulates PD's permeability by anchoring actin filaments to PD.

Data availability

All data generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided for related Figures shown in the manuscript.

Article and author information

Author details

  1. Min Diao

    Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, China
    Competing interests
    The authors declare that no competing interests exist.
  2. Sulin Ren

    Institute of Botany, Chinese Academy of Sciences, Beijing, China
    Competing interests
    The authors declare that no competing interests exist.
  3. Qiannan Wang

    Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, China
    Competing interests
    The authors declare that no competing interests exist.
  4. Lichao Qian

    MOE Key Laboratory of Bioinformatics, Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing, China
    Competing interests
    The authors declare that no competing interests exist.
  5. Jiangfeng Shen

    Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, China
    Competing interests
    The authors declare that no competing interests exist.
  6. Yule Liu

    MOE Key Laboratory of Bioinformatics, Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing, China
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-4423-6045
  7. Shanjin Huang

    Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, China
    For correspondence
    sjhuang@tsinghua.edu.cn
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-9517-2515

Funding

National Natural Science Foundation of China (31471266; 31671390)

  • Shanjin Huang

National Natural Science Foundation of China (31121065)

  • Yule Liu

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

Reviewing Editor

  1. Gary Stacey, University of Missouri, United States

Publication history

  1. Received: March 1, 2018
  2. Accepted: August 15, 2018
  3. Accepted Manuscript published: August 16, 2018 (version 1)
  4. Version of Record published: September 6, 2018 (version 2)
  5. Version of Record updated: May 1, 2019 (version 3)

Copyright

© 2018, Diao 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. Min Diao
  2. Sulin Ren
  3. Qiannan Wang
  4. Lichao Qian
  5. Jiangfeng Shen
  6. Yule Liu
  7. Shanjin Huang
(2018)
Arabidopsis formin 2 regulates cell-to-cell trafficking by capping and stabilizing actin filaments at plasmodesmata
eLife 7:e36316.
https://doi.org/10.7554/eLife.36316

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