A viral transcription factor exhibits antiviral RNA silencing suppression activity independent of its nuclear localization

J Gen Virol. 2014 Dec;95(Pt 12):2831-2837. doi: 10.1099/vir.0.067884-0. Epub 2014 Aug 20.


Viral suppressors of RNA silencing (VSRs) are critical for the success of virus infection and efficient accumulation of virus progeny. The chrysanthemum virus B p12 protein acts as a transcription factor to regulate cell size and proliferation favourable for virus infection. Here, we showed that the p12 protein suppressed RNA silencing and was able to complement a VSR-deficient unrelated virus. Moreover, p12 counter-silencing activity could be uncoupled from its function as a transcription factor in the nucleus. The altered p12 protein, which lacked a nuclear localization signal and was not imported into the nucleus, was able to suppress RNA silencing as efficiently as the native protein. The data revealed new aspects of p12 functioning and identified a novel role for this viral zinc-finger transcription factor. The results provided a general insight into one of the activities of the p12 protein, which appeared to possess more than one function.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Active Transport, Cell Nucleus
  • Genes, Viral
  • MicroRNAs
  • Mutation
  • Nuclear Localization Signals
  • Plant Leaves / virology
  • Plant Viruses / genetics
  • Plant Viruses / metabolism*
  • RNA Interference*
  • Tobacco / virology
  • Transcription Factors / genetics
  • Transcription Factors / metabolism*
  • Viral Proteins / genetics
  • Viral Proteins / metabolism*


  • MicroRNAs
  • Nuclear Localization Signals
  • Transcription Factors
  • Viral Proteins