The Sendai virus nonstructural C proteins specifically inhibit viral mRNA synthesis

Virology. 1992 Aug;189(2):647-56. doi: 10.1016/0042-6822(92)90588-g.


An in vitro transcription system for paramyxoviruses is described, in which polymerase-free templates are combined with cell extracts containing polymerase made in vivo via transfected plasmids. Both P and L are required for polymerase activity, and both must be coexpressed for optimum activity. mRNA synthesis here was found to be inversely proportional to the level of C expression, whereas defective interfering genome replication was largely unaffected by the level of C in the extract. The inhibition of transcription appeared to be due to the C' and C, but not the Y1 and Y2 proteins, and only occurred when C'/C was coexpressed with P and L. C'/C appears to intervene during polymerase formation, possibly by forming polymerase complexes which are inactive for transcription, but still competent for genome replication.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Base Sequence
  • Cells, Cultured
  • Gene Expression Regulation, Viral*
  • In Vitro Techniques
  • Molecular Sequence Data
  • Mutagenesis, Site-Directed
  • Oligodeoxyribonucleotides / chemistry
  • Parainfluenza Virus 1, Human / genetics*
  • RNA, Messenger / biosynthesis
  • RNA, Viral / biosynthesis
  • Transcription, Genetic
  • Viral Proteins / genetics*
  • Viral Proteins / metabolism


  • Oligodeoxyribonucleotides
  • RNA, Messenger
  • RNA, Viral
  • Viral Proteins
  • nonstructural C protein, Sendai virus