Host casein kinase 1-mediated phosphorylation modulates phase separation of a rhabdovirus phosphoprotein and virus infection

Abstract

Liquid-liquid phase separation (LLPS) plays important roles in forming cellular membraneless organelles. However, how host factors regulate LLPS of viral proteins during negative-sense RNA (NSR) virus infection is largely unknown. Here, we used Barley yellow striate mosaic virus (BYSMV) as a model to demonstrate regulation of host casein kinase 1 in phase separation and infection of NSR viruses. We first found that the BYSMV phosphoprotein (P) formed spherical granules with liquid properties and recruited viral nucleotide (N) and polymerase (L) proteins in vivo. Moreover, the P-formed granules were tethered to the ER/actin network for trafficking and fusion. BYSMV P alone formed droplets and incorporated the N protein and the 5′ trailer of genomic RNA in vitro. Interestingly, phase separation of BYSMV P was inhibited by host casein kinase 1 (CK1)-dependent phosphorylation of an intrinsically disordered P protein region. Genetic assays demonstrated that the unphosphorylated mutant of BYSMV P exhibited condensed phase, which promoted viroplasm formation and virus replication. Whereas, the phosphorylation-mimic mutant existed in diffuse phase state for virus transcription. Collectively, our results demonstrate that host CK1 modulates phase separation of the viral P protein and virus infection.

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

Article and author information

Author details

  1. Xiao-Dong Fang

    College of Biological Sciences, China Agricultural University, Beijing, China
    Competing interests
    The authors declare that no competing interests exist.
  2. Qiang Gao

    College of Biological Sciences, China Agricultural University, Beijing, China
    Competing interests
    The authors declare that no competing interests exist.
  3. Ying Zang

    College of Biological Sciences, China Agricultural University, Beijing, China
    Competing interests
    The authors declare that no competing interests exist.
  4. Ji-Hui Qiao

    College of Biological Sciences, China Agricultural University, Beijing, China
    Competing interests
    The authors declare that no competing interests exist.
  5. Dong-Min Gao

    College of Biological Sciences, China Agricultural University, Beijing, China
    Competing interests
    The authors declare that no competing interests exist.
  6. Wen-Ya Xu

    College of Biological Sciences, China Agricultural University, Beijing, China
    Competing interests
    The authors declare that no competing interests exist.
  7. Ying Wang

    College of Plant Protection, China Agricultural University, Beijing, China
    Competing interests
    The authors declare that no competing interests exist.
  8. Dawei Li

    State Key Laboratory of Agro-Biotechnology, China Agricultural University, Beijing, China
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4133-1263
  9. Xian-Bing Wang

    College of Biological Sciences, China Agricultural University, Beijing, China
    For correspondence
    wangxianbing@cau.edu.cn
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-3082-2462

Funding

National Natural Science Foundation of China (31872920)

  • Xian-Bing Wang

National Natural Science Foundation of China (32102150)

  • Qiang Gao

China Postdoctoral Science Foundation (2021T140713)

  • Qiang Gao

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

Reviewing Editor

  1. Savithramma P Dinesh-Kumar, University of California, Davis, United States

Version history

  1. Received: October 20, 2021
  2. Preprint posted: November 16, 2021 (view preprint)
  3. Accepted: February 21, 2022
  4. Accepted Manuscript published: February 22, 2022 (version 1)
  5. Accepted Manuscript updated: February 24, 2022 (version 2)
  6. Version of Record published: March 1, 2022 (version 3)

Copyright

© 2022, Fang 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. Xiao-Dong Fang
  2. Qiang Gao
  3. Ying Zang
  4. Ji-Hui Qiao
  5. Dong-Min Gao
  6. Wen-Ya Xu
  7. Ying Wang
  8. Dawei Li
  9. Xian-Bing Wang
(2022)
Host casein kinase 1-mediated phosphorylation modulates phase separation of a rhabdovirus phosphoprotein and virus infection
eLife 11:e74884.
https://doi.org/10.7554/eLife.74884

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https://doi.org/10.7554/eLife.74884

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