Neutralization of mobile antiviral small RNA through peroxisomal import

  • Nature Plants 3, Article number: 17094 (2017)
  • doi:10.1038/nplants.2017.94
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In animals, certain viral proteins are targeted to peroxisomes to dampen the antiviral immune response mediated by these organelles1,​2,​3. In plants, RNA interference (RNAi) mediated by small interfering (si)RNA is the main antiviral defence mechanism. To protect themselves against the cell- and non-cell autonomous effects of RNAi, viruses produce viral suppressors of RNA silencing (VSR)4, whose study is crucial to properly understand the biological cycle of plant viruses and potentially find new solutions to control these pathogens. By combining biochemical approaches, cell-specific inhibition of RNAi movement and peroxisome isolation, we show here that one such VSR, the peanut clump virus (PCV)-encoded P15, isolates siRNA from the symplasm by delivering them into the peroxisomal matrix. Infection with PCV lacking this ability reveals that piggybacking of these VSR-bound nucleic acids into peroxisomes potentiates viral systemic movement by preventing the spread of antiviral siRNA. Collectively, these results highlight organellar confinement of antiviral molecules as a novel pathogenic strategy that may have its direct counterpart in other plant and animal viruses.

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This work was supported by a research grant from Agence Nationale de la Recherche (ANR-14-CE19-0014-01). It was also performed under the framework of the LABEX: ANR-10-LABX-0036_NETRNA and benefits from a funding from the state managed by the French National Research Agency as part of the Investments for the future program. We deeply thank S. Reumann for advice on plant peroxisome isolation and S. Bouzoubaa for advice on PCV purification.

Author information


  1. Institut de Biologie Moléculaire des Plantes du CNRS, UPR2357, Université de Strasbourg, F-67000 Strasbourg, France

    • M. Incarbone
    • , A. Zimmermann
    • , M. Erhardt
    • , F. Michel
    •  & P. Dunoyer
  2. Institut de Biologie Moléculaire et Cellulaire du CNRS, Plateforme Protéomique Strasbourg – Esplanade, FRC1589, F-67000 Strasbourg, France

    • P. Hammann


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M.I. and P.D. designed the experiments. M.I. performed transgene construction, plant transformation and manipulation, viral purification and infection, immunoprecipitation and peroxisome isolation. M.I. and A.Z. performed RNA and protein extraction, RNA and protein gel blot analysis with the assistance of F.M. P.H. performed MS-MS protein analyses, while M.I. and M.E. performed immunohistochemistry. P.D. and M.I. wrote the manuscript and prepared the figures.

Competing interests

The authors declare no competing financial interests.

Corresponding author

Correspondence to P. Dunoyer.

Supplementary information

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    Supplementary Methods, Supplementary References, Supplementary Figures 1–10, Supplementary Source Data, Supplementary Raw Data 1–10.

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