Virus-induced diseases cause severe damage to cultivated plants, resulting in crop losses. Certain plant–virus interactions allow disease recovery at later stages of infection and have the potential to reveal important molecular targets for achieving disease control. Although recovery is known to involve antiviral RNA silencing1,2, the specific components of the many plant RNA silencing pathways3 required for recovery are not known. We found that Arabidopsis thaliana plants infected with oilseed rape mosaic virus (ORMV) undergo symptom recovery. The recovered leaves contain infectious, replicating virus, but exhibit a loss of viral suppressor of RNA silencing (VSR) protein activity. We demonstrate that recovery depends on the 21–22 nt siRNA-mediated post-transcriptional gene silencing (PTGS) pathway and on components of a transcriptional gene silencing (TGS) pathway that is known to facilitate non-cell-autonomous silencing signalling. Collectively, our observations indicate that recovery reflects the establishment of a tolerant state in infected tissues and occurs following robust delivery of antiviral secondary siRNAs from source to sink tissues, and establishment of a dosage able to block the VSR activity involved in the formation of disease symptoms.
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Ghoshal, B. & Sanfaçon, H. Symptom recovery in virus-infected plants: revisiting the role of RNA silencing mechanisms. Virology 479–480, 167–179 (2015).
Ma, X. et al. Different roles for RNA silencing and RNA processing components in virus recovery and virus-induced gene silencing in plants. J. Exp. Bot. 66, 919–932 (2015).
Bologna, N. G. & Voinnet, O. The diversity, biogenesis, and activities of endogenous silencing small RNAs in Arabidopsis. Annu Rev. Plant Biol. 65, 473–503 (2014).
Csorba, T., Kontra, L. & Burgyan, J. Viral silencing suppressors: tools forged to fine-tune host-pathogen coexistence. Virology 479–480C, 85–103 (2015).
Glazov, E. et al. A gene encoding an RNase D exonuclease-like protein is required for post-transcriptional silencing in Arabidopsis. Plant J. 35, 342–349 (2003).
Voinnet, O., Pinto, Y. M. & Baulcombe, D. C. Suppression of gene silencing: a general strategy used by diverse DNA and RNA viruses of plants. Proc. Natl Acad. Sci. USA 96, 14147–14152 (1999).
Csorba, T., Bovi, A., Dalmay, T. & Burgyan, J. The p122 subunit of Tobacco mosaic virus replicase is a potent silencing suppressor and compromises both small interfering RNA- and microRNA-mediated pathways. J. Virol. 81, 11768–11780 (2007).
Dalmay, T., Hamilton, A., Mueller, E. & Baulcombe, D. C. Potato virus X amplicons in Arabidopsis mediate genetic and epigenetic gene silencing. Plant Cell 12, 369–379 (2000).
Blevins, T. et al. Four plant Dicers mediate viral small RNA biogenesis and DNA virus induced silencing. Nucleic Acids Res. 34, 6233–6246 (2006).
Hu, Q. et al. Specific impact of tobamovirus infection on the Arabidopsis small RNA profile. PLoS One 6, e19549 (2011).
Himber, C., Dunoyer, P., Moissiard, G., Ritzenthaler, C. & Voinnet, O. Transitivity-dependent and -independent cell-to-cell movement of RNA silencing. EMBO J. 22, 4523–4533 (2003).
Ye, K. & Patel, D. J. RNA silencing suppressor p21 of Beet yellows virus forms an RNA binding octameric ring structure. Structure 13, 1375–1384 (2005).
Chapman, E. J., Prokhnevsky, A. I., Gopinath, K., Dolja, V. V. & Carrington, J. C. Viral RNA silencing suppressors inhibit the microRNA pathway at an intermediate step. Genes Dev. 18, 1179–1186 (2004).
Morel, J. B. et al. Fertile hypomorphic ARGONAUTE (ago1) mutants impaired in post-transcriptional gene silencing and virus resistance. Plant Cell 14, 629–639 (2002).
Vaucheret, H. Plant ARGONAUTES. Trends Plant Sci. 13, 350–358 (2008).
Kim, S. et al. Two cap-binding proteins CBP20 and CBP80 are involved in processing primary microRNAs. Plant Cell Physiol. 49, 1634–1644 (2008).
Vazquez, F., Gasciolli, V., Crété, P. & Vaucheret, H. The nuclear dsRNA binding protein HYL1 is required for microRNA accumulation and plant development, but not posttranscriptional transgene silencing. Curr. Biol. 14, 346–351 (2004).
Xie, Z. et al. Expression of Arabidopsis miRNA genes. Plant Physiol. 138, 2145–2154 (2005).
Lobbes, D., Rallapalli, G., Schmidt, D. D., Martin, C. & Clarke, J. SERRATE: a new player on the plant microRNA scene. EMBO Rep. 7, 1052–1058 (2006).
Gregory, B. D. et al. A link between RNA metabolism and silencing affecting Arabidopsis development. Dev. Cell 14, 854–866 (2008).
Montgomery, T. A. et al. Specificity of ARGONAUTE7-miR390 interaction and dual functionality in TAS3 trans-acting siRNA formation. Cell 133, 128–141 (2008).
Jouannet, V. et al. Cytoplasmic Arabidopsis AGO7 accumulates in membrane-associated siRNA bodies and is required for ta-siRNA biogenesis. EMBO J. 31, 1704–1713 (2012).
Deleris, A. et al. Hierarchical action and inhibition of plant Dicer-like proteins in antiviral defense. Science 313, 68–71 (2006).
Donaire, L. et al. Structural and genetic requirements for the biogenesis of Tobacco rattle virus-derived small interfering RNAs. J. Virol. 82, 5167–5177 (2008).
Bouché, N., Lauressergues, D., Gasciolli, V. & Vaucheret, H. An antagonistic function for Arabidopsis DCL2 in development and a new function for DCL4 in generating viral siRNAs. EMBO J. 25, 3347–3356 (2006).
Moissiard, G., Parizotto, E. A., Himber, C. & Voinnet, O. Transitivity in Arabidopsis can be primed, requires the redundant action of the antiviral Dicer-like 4 and Dicer-like 2, and is compromised by viral-encoded suppressor proteins. RNA 13, 1268–1278 (2007).
Gazzani, S., Lawrenson, T., Woodward, C., Headon, D. & Sablowski, R. A link between mRNA turnover and RNA interference in Arabidopsis. Science 306, 1046–1048 (2004).
Moreno, A. B. et al. Cytoplasmic and nuclear quality control and turnover of single-stranded RNA modulate post-transcriptional gene silencing in plants. Nucleic Acids Res. 41, 4699–4708 (2013).
Potuschak, T. et al. The exoribonuclease XRN4 is a component of the ethylene response pathway in Arabidopsis. Plant Cell 18, 3047–3057 (2006).
Olmedo, G. et al. ETHYLENE-INSENSITIVE5 encodes a 5’→3’ exoribonuclease required for regulation of the EIN3-targeting F-box proteins EBF1/2. Proc. Natl Acad. Sci. USA 103, 13286–13293 (2006).
De Vleesschauwer, D., Xu, J. & Höfte, M. Making sense of hormone-mediated defense networking: from rice to Arabidopsis. Front Plant Sci. 5, 611 (2014).
Smith, L. M. et al. An SNF2 protein associated with nuclear RNA silencing and the spread of a silencing signal between cells in Arabidopsis. Plant Cell 19, 1507–1521 (2007).
Dunoyer, P., Himber, C., Ruiz-Ferrer, V., Alioua, A. & Voinnet, O. Intra- and intercellular RNA interference in Arabidopsis thaliana requires components of the microRNA and heterochromatic silencing pathways. Nat. Genet. 39, 848–856 (2007).
Eamens, A., Vaistij, F. E. & Jones, L. NRPD1a and NRPD1b are required to maintain post-transcriptional RNA silencing and RNA-directed DNA methylation in Arabidopsis. Plant J. 55, 596–606 (2008).
Brosnan, C. A. et al. Nuclear gene silencing directs reception of long-distance mRNA silencing in Arabidopsis. Proc. Natl Acad. Sci. USA 104, 14741–14746 (2007).
Matzke, M. A. & Mosher, R. A. RNA-directed DNA methylation: an epigenetic pathway of increasing complexity. Nat. Rev. Genet. 15, 394–408 (2014).
Roberts, A. G. et al. Phloem unloading in sink leaves of Nicotiana benthamiana: comparison of a fluorescent solute with a fluorescent virus. Plant Cell 9, 1381–1396 (1997).
Voinnet, O., Vain, P., Angell, S. & Baulcombe, D. C. Systemic spread of sequence-specific transgene RNA degradation in plants is initiated by localized introduction of ectopic promoterless DNA. Cell 95, 177–187 (1998).
Imlau, A., Truernit, E. & Sauer, N. Cell-to-cell and long-distance trafficking of green fluorescent protein in the phloem and symplastic unloading of the protein into sink tissues. Plant Cell 11, 309–322 (1999).
Watanabe, T. et al. Isolation from Tobacco mosaic virus-infected tobacco of a solubilized template-specific RNA-dependent RNA polymerase containing a 126K/183K protein heterodimer. J. Virol. 73, 2633–2640 (1999).
Hagiwara-Komoda, Y. et al. Overexpression of a host factor TOM1 inhibits Tomato mosaic virus propagation and suppression of RNA silencing. Virology 376, 132–139 (2008).
Vogler, H. et al. Modification of small RNAs associated with suppression of RNA silencing by tobamovirus replicase protein. J. Virol. 81, 10379–10388 (2007).
Kurihara, Y. et al. Binding of tobamovirus replication protein with small RNA duplexes. J. Gen. Virol. 88, 2347–2352 (2007).
Malpica-Lopez, N. et al. Revisiting the roles of tobamovirus replicase complex proteins in viral replication and silencing suppression. Mol. Plant Microbe Interact. 31, 125–144 (2018).
This work was supported by funding from the Swiss National Science Foundation (SNF, grant 124940 and 144084 to MH, grant 126329 to FV), the Agence National de la Recherche Scientifique (ANR, grants ANR-08-BLAN-0244 and ANR-13-KBBE-005 to M.H.), the Région Alsace (PhD fellowship to N.P.) and the Centre National de la Recherche Scientifique (CNRS, grant PICS06702 to E.J.P. and M.H.). We would like to thank E. Bucher and T. Blevins for helpful discussions and suggestions, and P. Dunoyer and R. Stadler for providing the SUC:SUL and SUC:GFP Arabidopsis lines, respectively. We thank P. Dunoyer for also providing the Col-0 lines expressing the TBSV p19 and the BYV p21 VSRs. We are grateful to M. Pooggin (INRA, Montpellier) for the anti-P125/P182 antibody. Furthermore, we would like to thank M. Böhrer and T. Blevins for their support with RNA blotting and hybridization, and M. DiDonato, A. Niehl, K. Amari and D. Windels for other technical assistance, discussions and critical comments.
The authors declare no competing interests.
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Kørner, C.J., Pitzalis, N., Peña, E.J. et al. Crosstalk between PTGS and TGS pathways in natural antiviral immunity and disease recovery. Nature Plants 4, 157–164 (2018). https://doi.org/10.1038/s41477-018-0117-x
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