RNA polymerase II phosphorylation: uncoupling from GAL4-VP16 directed open complex formation and transcription in a reconstituted system

Nucleic Acids Res. 1994 Nov 25;22(23):4958-62. doi: 10.1093/nar/22.23.4958.


An activated transcription system was constructed using substantially purified liver factors, Hela TFIID and GAL4-VP16. The system was used to study the relationship between RNA polymerase II large subunit phosphorylation and other ATP-dependent processes occurring during activated transcription. When C-terminal domain (CTD) kinase activity was inhibited, activator dependent open promoter complex formation proceeded normally. These open complexes could function to produce RNA in the absence of CTD phosphorylation, although the level of RNA produced was changed somewhat. The results demonstrate that RNA polymerase II CTD phosphorylation is not generally required for the formation of activator-dependent, functional open promoter complexes. Taken together with prior results the experiments suggest that a requirement for CTD phosphorylation may be situation-dependent and thus serve a regulatory function.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adenosine Triphosphate / physiology*
  • Amino Acid Sequence
  • Cell-Free System
  • Fungal Proteins / physiology*
  • HeLa Cells
  • Humans
  • Isoquinolines / pharmacology
  • Molecular Sequence Data
  • Phosphorylation / drug effects
  • Promoter Regions, Genetic / physiology
  • Protein Kinase Inhibitors
  • Protein Kinases*
  • RNA Polymerase II / metabolism*
  • Trans-Activators / physiology*
  • Transcription Factor TFIID
  • Transcription Factors / isolation & purification
  • Transcription Factors / physiology
  • Transcription, Genetic / drug effects
  • Transcription, Genetic / physiology*


  • Fungal Proteins
  • Gal-VP16
  • Isoquinolines
  • Protein Kinase Inhibitors
  • Trans-Activators
  • Transcription Factor TFIID
  • Transcription Factors
  • N-(2-(methylamino)ethyl)-5-isoquinolinesulfonamide
  • Adenosine Triphosphate
  • Protein Kinases
  • carboxy-terminal domain kinase
  • RNA Polymerase II