mda-5, but not RIG-I, is a common target for paramyxovirus V proteins

Virology. 2007 Mar 1;359(1):190-200. doi: 10.1016/j.virol.2006.09.023. Epub 2006 Oct 16.


The induction of IFN-beta by the paramyxovirus PIV5 (formerly known as SV5) is limited by the action of the viral V protein that targets the cellular RNA helicase mda-5. Here we show that 12 other paramyxoviruses also target mda-5 by a direct interaction between the conserved cysteine-rich C-terminus of their V proteins and the helicase domain of mda-5. The inhibition of IFN-beta induction is not species-restricted, being observed in a range of mammalian cells as well as in avian cells, and we show that the inhibition of mda-5 function is also not restricted to mammalian cells. In contrast, the V proteins do not bind to the related RNA helicase RIG-I and do not inhibit its activity. The relative contributions of mda-5 and RIG-I to IFN-beta induction are discussed.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Birds
  • Cattle
  • Cell Line
  • Chlorocebus aethiops
  • DEAD-box RNA Helicases / antagonists & inhibitors*
  • DEAD-box RNA Helicases / chemistry
  • DEAD-box RNA Helicases / metabolism*
  • Humans
  • Immunoprecipitation
  • Interferon-beta / biosynthesis
  • Molecular Sequence Data
  • Parainfluenza Virus 5 / physiology*
  • Protein Binding
  • Protein Interaction Mapping
  • Protein Structure, Tertiary
  • Sequence Homology, Amino Acid
  • Two-Hybrid System Techniques
  • Viral Structural Proteins / chemistry
  • Viral Structural Proteins / metabolism*


  • V protein, Simian parainfluenza virus 5
  • Viral Structural Proteins
  • Interferon-beta
  • DEAD-box RNA Helicases