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.

Data availability

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.

Metrics

  • 1,446
    Page views
  • 311
    Downloads
  • 11
    Citations

Article citation count generated by polling the highest count across the following sources: Crossref, PubMed Central, Scopus.

Download links

A two-part list of links to download the article, or parts of the article, in various formats.

Downloads (link to download the article as PDF)

Open citations (links to open the citations from this article in various online reference manager services)

Cite this article (links to download the citations from this article in formats compatible with various reference manager tools)

  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

Further reading

    1. Microbiology and Infectious Disease
    2. Plant Biology
    Christopher Kesten, Valentin Leitner ... Clara Sanchez-Rodriguez
    Research Article

    Purinergic signaling activated by extracellular nucleotides and their derivative nucleosides trigger sophisticated signaling networks. The outcome of these pathways determine the capacity of the organism to survive under challenging conditions. Both extracellular ATP (eATP) and Adenosine (eAdo) act as primary messengers in mammals, essential for immunosuppressive responses. Despite the clear role of eATP as a plant damage-associated molecular pattern, the function of its nucleoside, eAdo, and of the eAdo/eATP balance in plant stress response remain to be fully elucidated. This is particularly relevant in the context of plant-microbe interaction, where the intruder manipulates the extracellular matrix. Here, we identify Ado as a main molecule secreted by the vascular fungus Fusarium oxysporum. We show that eAdo modulates the plant's susceptibility to fungal colonization by altering the eATP-mediated apoplastic pH homeostasis, an essential physiological player during the infection of this pathogen. Our work indicates that plant pathogens actively imbalance the apoplastic eAdo/eATP levels as a virulence mechanism.

    1. Plant Biology
    2. Structural Biology and Molecular Biophysics
    Jinping Lu, Ingo Dreyer ... Rainer Hedrich
    Research Article

    To fire action-potential-like electrical signals, the vacuole membrane requires the two-pore channel TPC1, formerly called SV channel. The TPC1/SV channel functions as a depolarization-stimulated, non-selective cation channel that is inhibited by luminal Ca2+. In our search for species-dependent functional TPC1 channel variants with different luminal Ca2+ sensitivity, we found in total three acidic residues present in Ca2+ sensor sites 2 and 3 of the Ca2+-sensitive AtTPC1 channel from Arabidopsis thaliana that were neutral in its Vicia faba ortholog and also in those of many other Fabaceae. When expressed in the Arabidopsis AtTPC1-loss-of-function background, wild-type VfTPC1 was hypersensitive to vacuole depolarization and only weakly sensitive to blocking luminal Ca2+. When AtTPC1 was mutated for these VfTPC1-homologous polymorphic residues, two neutral substitutions in Ca2+ sensor site 3 alone were already sufficient for the Arabidopsis At-VfTPC1 channel mutant to gain VfTPC1-like voltage and luminal Ca2+ sensitivity that together rendered vacuoles hyperexcitable. Thus, natural TPC1 channel variants exist in plant families which may fine-tune vacuole excitability and adapt it to environmental settings of the particular ecological niche.