Double-stranded RNA binding may be a general plant RNA viral strategy to suppress RNA silencing
- PMID: 16731914
- PMCID: PMC1472586
- DOI: 10.1128/JVI.01963-05
Double-stranded RNA binding may be a general plant RNA viral strategy to suppress RNA silencing
Abstract
In plants, RNA silencing (RNA interference) is an efficient antiviral system, and therefore successful virus infection requires suppression of silencing. Although many viral silencing suppressors have been identified, the molecular basis of silencing suppression is poorly understood. It is proposed that various suppressors inhibit RNA silencing by targeting different steps. However, as double-stranded RNAs (dsRNAs) play key roles in silencing, it was speculated that dsRNA binding might be a general silencing suppression strategy. Indeed, it was shown that the related aureusvirus P14 and tombusvirus P19 suppressors are dsRNA-binding proteins. Interestingly, P14 is a size-independent dsRNA-binding protein, while P19 binds only 21-nucleotide ds-sRNAs (small dsRNAs having 2-nucleotide 3' overhangs), the specificity determinant of the silencing system. Much evidence supports the idea that P19 inhibits silencing by sequestering silencing-generated viral ds-sRNAs. In this study we wanted to test the hypothesis that dsRNA binding is a general silencing suppression strategy. Here we show that many plant viral silencing suppressors bind dsRNAs. Beet yellows virus Peanut P21, clump virus P15, Barley stripe mosaic virus gammaB, and Tobacco etch virus HC-Pro, like P19, bind ds-sRNAs size-selectively, while Turnip crinkle virus CP is a size-independent dsRNA-binding protein, which binds long dsRNAs as well as ds-sRNAs. We propose that size-selective ds-sRNA-binding suppressors inhibit silencing by sequestering viral ds-sRNAs, whereas size-independent dsRNA-binding suppressors inactivate silencing by sequestering long dsRNA precursors of viral sRNAs and/or by binding ds-sRNAs. The findings that many unrelated silencing suppressors bind dsRNA suggest that dsRNA binding is a general silencing suppression strategy which has evolved independently many times.
Figures
Similar articles
-
Aureusvirus P14 is an efficient RNA silencing suppressor that binds double-stranded RNAs without size specificity.J Virol. 2005 Jun;79(11):7217-26. doi: 10.1128/JVI.79.11.7217-7226.2005. J Virol. 2005. PMID: 15890960 Free PMC article.
-
Double-stranded RNA-binding proteins could suppress RNA interference-mediated antiviral defences.J Gen Virol. 2003 Apr;84(Pt 4):975-980. doi: 10.1099/vir.0.18987-0. J Gen Virol. 2003. PMID: 12655099
-
A viral protein suppresses RNA silencing and binds silencing-generated, 21- to 25-nucleotide double-stranded RNAs.EMBO J. 2002 Jun 17;21(12):3070-80. doi: 10.1093/emboj/cdf312. EMBO J. 2002. PMID: 12065420 Free PMC article.
-
Plant viral suppressors of RNA silencing.Virus Res. 2004 Jun 1;102(1):97-108. doi: 10.1016/j.virusres.2004.01.020. Virus Res. 2004. PMID: 15068885 Review.
-
Effects and side-effects of viral RNA silencing suppressors on short RNAs.Trends Plant Sci. 2004 Feb;9(2):76-83. doi: 10.1016/j.tplants.2003.12.010. Trends Plant Sci. 2004. PMID: 15102373 Review.
Cited by
-
Functional Characterization of RNA Silencing Suppressor P0 from Pea Mild Chlorosis Virus.Int J Mol Sci. 2020 Sep 27;21(19):7136. doi: 10.3390/ijms21197136. Int J Mol Sci. 2020. PMID: 32992609 Free PMC article.
-
Sugarcane Streak Mosaic Virus P1 Attenuates Plant Antiviral Immunity and Enhances Potato Virus X Infection in Nicotiana benthamiana.Cells. 2022 Sep 14;11(18):2870. doi: 10.3390/cells11182870. Cells. 2022. PMID: 36139443 Free PMC article.
-
Genomics of helper component proteinase reveals effective strategy for papaya ringspot virus resistance.Mol Biotechnol. 2010 Jan;44(1):22-9. doi: 10.1007/s12033-009-9205-5. Epub 2009 Aug 12. Mol Biotechnol. 2010. PMID: 19672730
-
Suppression of antiviral silencing by cucumber mosaic virus 2b protein in Arabidopsis is associated with drastically reduced accumulation of three classes of viral small interfering RNAs.Plant Cell. 2007 Jun;19(6):2053-63. doi: 10.1105/tpc.106.047449. Epub 2007 Jun 22. Plant Cell. 2007. PMID: 17586651 Free PMC article.
-
Diverging affinity of tospovirus RNA silencing suppressor proteins, NSs, for various RNA duplex molecules.J Virol. 2010 Nov;84(21):11542-54. doi: 10.1128/JVI.00595-10. Epub 2010 Aug 25. J Virol. 2010. PMID: 20739523 Free PMC article.
References
-
- Atreya, C. D., P. L. Atreya, D. W. Thornbury, and T. P. Pirone. 1992. Site-directed mutations in the potyvirus HC-Pro gene affect helper component activity, virus accumulation, and symptom expression in infected tobacco plants. Virology 191:106-111. - PubMed
-
- Baulcombe, D. 2005. RNA silencing. Trends Biochem. Sci. 30:290-293. - PubMed
-
- Baulcombe, D. 2004. RNA silencing in plants. Nature 431:356-363. - PubMed
-
- Baulcombe, D. C., and A. Molnar. 2004. Crystal structure of p19—a universal suppressor of RNA silencing. Trends Biochem. Sci. 29:279-281. - PubMed
-
- Bennasser, Y., S. Y. Le, M. Benkirane, and K. T. Jeang. 2005. Evidence that HIV-1 encodes an siRNA and a suppressor of RNA silencing. Immunity 22:607-619. - PubMed
Publication types
MeSH terms
Substances
LinkOut - more resources
Full Text Sources
Other Literature Sources
Research Materials
Miscellaneous