Tritimovirus P1 functions as a suppressor of RNA silencing and an enhancer of disease symptoms

Brock A. Young, Drake C. Stenger, Feng Qu, T. Jack Morris, Satyanarayana Tatineni, Roy French

Research output: Contribution to journalArticle

41 Scopus citations


Wheat streak mosaic virus (WSMV) is an eriophyid mite-transmitted virus of the genus Tritimovirus, family Potyviridae. Complete deletion of helper component-proteinase (HC-Pro) has no effect on WSMV virulence or disease synergism, suggesting that a different viral protein suppresses RNA silencing. RNA silencing suppression assays using Nicotiana benthamiana 16C plants expressing GFP were conducted with each WSMV protein; only P1 suppressed RNA silencing. Accumulation of GFP siRNAs was markedly reduced in leaves infiltrated with WSMV P1 at both 3 and 6 days post infiltration relative to WSMV HC-Pro and the empty vector control. On the other hand, helper component-proteinase (HC-Pro) of two species in the mite-transmitted genus Rymovirus, family Potyviridae was demonstrated to be a suppressor of RNA silencing. Symptom enhancement assays were conducted by inoculating Potato virus X (PVX) onto transgenic N. benthamiana. Symptoms produced by PVX were more severe on transgenic plants expressing WSMV P1 or potyvirus HC-Pro compared to transgenic plants expressing GFP or WSMV HC-Pro.

Original languageEnglish (US)
Pages (from-to)672-677
Number of pages6
JournalVirus Research
Issue number2
Publication statusPublished - Feb 1 2012



  • Post-transcriptional gene silencing suppression
  • Potyviridae
  • Wheat streak mosaic virus

ASJC Scopus subject areas

  • Cancer Research
  • Virology
  • Infectious Diseases

Cite this

Young, B. A., Stenger, D. C., Qu, F., Morris, T. J., Tatineni, S., & French, R. (2012). Tritimovirus P1 functions as a suppressor of RNA silencing and an enhancer of disease symptoms. Virus Research, 163(2), 672-677.