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The Tombusvirus-encoded P19: from irrelevance to elegance

Nature Reviews Microbiology volume 4, pages 405–411 (2006)Cite this article

Abstract

Since its discovery in the late 1980s, the status of the Tombusvirus-encoded p19 protein (P19) changed from being thought obsolete to its identification a decade later as an important viral pathogenicity factor. The recent finding that P19 suppresses RNA interference (RNAi) by appropriating short interfering RNAs led to its widespread use as an RNAi-probing tool in various plant and animal models. Here, I discuss how our knowledge of p19 has developed over the years, with emphasis on the relevance of understanding its biological roles during Tombusvirus infection of plants.

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Figure 1: Gene-expression strategy of the Tombusvirus p19 as illustrated for Tomato bushy stunt virus (TBSV).
Figure 2: A model showing how RNA interference (RNAi) and P19 influence Tombusvirus infection of plants.
Figure 3: P19–short interfering (si)RNA structure: side view (top) and view from the dimer-base up towards siRNA (bottom).

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Acknowledgements

I thank R. Omarov and K.-B. G. Scholthof for providing helpful suggestions, and J. Hsieh for customizing the P19 structure representation. Funding for our TBSV work was provided by the National Science Foundation.

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Authors and Affiliations

  1. Department of Plant Pathology and Microbiology and Intercollegiate Faculty of Virology, Texas A&M University, 2132 TAMU, College Station, 77843, Texas, USA

    Herman B. Scholthof

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Scholthof, H. The Tombusvirus-encoded P19: from irrelevance to elegance. Nat Rev Microbiol 4, 405–411 (2006). https://doi.org/10.1038/nrmicro1395

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