Autophagy functions as an antiviral mechanism against geminiviruses in plants

Abstract

Autophagy is an evolutionarily conserved process that recycles damaged or unwanted cellular components, and has been linked to plant immunity. However, how autophagy contributes to plant immunity is unknown. Here we reported that the plant autophagic machinery targets the virulence factor βC1 of Cotton leaf curl Multan virus (CLCuMuV) for degradation through its interaction with the key autophagy protein ATG8. A V32A mutation in βC1 abolished its interaction with NbATG8f, and virus carrying βC1V32A showed increased symptoms and viral DNA accumulation in plants. Furthermore, silencing of autophagy-related genes ATG5 and ATG7 reduced plant resistance to the DNA viruses CLCuMuV, Tomato yellow leaf curl virus, and Tomato yellow leaf curl China virus, whereas activating autophagy by silencing GAPC genes enhanced plant resistance to viral infection. Thus, autophagy represents a novel anti-pathogenic mechanism that plays an important role in antiviral immunity in plants.

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Author details

  1. Yakupjan Haxim

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

    Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, China
    Competing interests
    The authors declare that no competing interests exist.
  3. Qi Jia

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

    Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, China
    Competing interests
    The authors declare that no competing interests exist.
  5. Xiyin Zheng

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

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

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

    Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, China
    Competing interests
    The authors declare that no competing interests exist.
  9. Yunjing Wang

    Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, China
    Competing interests
    The authors declare that no competing interests exist.
  10. Han shaojie

    Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, China
    Competing interests
    The authors declare that no competing interests exist.
  11. Jiaxuan Cheng

    Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, China
    Competing interests
    The authors declare that no competing interests exist.
  12. Qi Yijun

    Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, China
    Competing interests
    The authors declare that no competing interests exist.
  13. Yiguo Hong

    Research Centre for Plant RNA Signaling, College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, China
    Competing interests
    The authors declare that no competing interests exist.
  14. Yule Liu

    Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, China
    For correspondence
    yuleliu@mail.tsinghua.edu.cn
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-4423-6045

Funding

National Natural Science Foundation of China (31530059)

  • Yule Liu

National Natural Science Foundation of China (31421001)

  • Yule Liu

National Natural Science Foundation of China (31470254)

  • Yule Liu

National Natural Science Foundation of China (31370180)

  • Yule Liu

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

Copyright

© 2017, Haxim 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. Yakupjan Haxim
  2. Asigul Ismayil
  3. Qi Jia
  4. Yan Wang
  5. Xiyin Zheng
  6. Tianyuan Chen
  7. Lichao Qian
  8. Na Liu
  9. Yunjing Wang
  10. Han shaojie
  11. Jiaxuan Cheng
  12. Qi Yijun
  13. Yiguo Hong
  14. Yule Liu
(2017)
Autophagy functions as an antiviral mechanism against geminiviruses in plants
eLife 6:e23897.
https://doi.org/10.7554/eLife.23897

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https://doi.org/10.7554/eLife.23897

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