Promoter melting by a stage-specific vaccinia virus transcription factor is independent of the presence of RNA polymerase

J C Vos, M Sasker, H.G. Stunnenberg

Research output: Contribution to JournalArticleAcademicpeer-review


Fractionation of an extract prepared from HeLa cells infected with vaccinia virus resulted in the separation of factors involved in vaccinia virus intermediate transcription. Two activities, VITF-A and VITF-B, in addition to the viral RNA polymerase are necessary and sufficient to direct intermediate transcription in vitro. VITF-B confers intermediate promoter specificity to an early-specific extract prepared from virus particles. A committed complex between VITF-B and the template can sequester VITF-A and RNA polymerase into a pre-initiation complex. VITF-B is further able to melt the promoter at the start site of transcription. Open complex formation is stimulated by ATP. In contrast to prokaryotic and eukaryotic pol III transcription, promoter melting is independent of the presence of RNA polymerase.

Original languageEnglish
Pages (from-to)105-13
Number of pages9
Issue number1
Publication statusPublished - 5 Apr 1991



  • Adenosine Triphosphate
  • Base Sequence
  • Cell Fractionation
  • DNA
  • DNA-Directed RNA Polymerases
  • Genetic Complementation Test
  • HeLa Cells
  • Heparin
  • Humans
  • Molecular Sequence Data
  • Plasmids
  • Potassium Permanganate
  • Promoter Regions, Genetic
  • Templates, Genetic
  • Transcription Factors
  • Transcription, Genetic
  • Vaccinia virus
  • Journal Article

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