Rapid switching of TFIIH between RNA polymerase I and II transcription and DNA repair in vivo

Mol Cell. 2002 Nov;10(5):1163-74. doi: 10.1016/s1097-2765(02)00709-8.


The transcription/repair factor TFIIH operates as a DNA helix opener in RNA polymerase II (RNAP2) transcription and nucleotide excision repair. To study TFIIH in vivo, we generated cell lines expressing functional GFP-tagged TFIIH. TFIIH was homogeneously distributed throughout the nucleus with nucleolar accumulations. We provide in vivo evidence for involvement of TFIIH in RNA polymerase I (RNAP1) transcription. Photobleaching revealed that TFIIH moves freely and gets engaged in RNAP1 and RNAP2 transcription for approximately 25 and approximately 6 s, respectively. TFIIH readily switches between transcription and repair sites (where it is immobilized for approximately 4 min) without large-scale alterations in composition. Our findings support a model of diffusion and random collision of individual components that permits a quick and versatile response to changing conditions.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • CHO Cells
  • Cell Nucleolus / metabolism
  • Cell Nucleus / metabolism
  • Cricetinae
  • Cytoplasm / metabolism
  • DNA / metabolism
  • DNA Damage
  • DNA Repair*
  • Dose-Response Relationship, Radiation
  • Green Fluorescent Proteins
  • Light
  • Luminescent Proteins / metabolism
  • Microscopy, Confocal
  • Models, Biological
  • RNA Polymerase I / chemistry*
  • RNA Polymerase I / metabolism
  • RNA Polymerase II / chemistry*
  • RNA Polymerase II / metabolism
  • Recombinant Fusion Proteins / metabolism
  • Time Factors
  • Transcription Factor TFIIH
  • Transcription Factors, TFII / chemistry
  • Transcription Factors, TFII / metabolism*
  • Transcription, Genetic
  • Transfection
  • Ultraviolet Rays


  • Luminescent Proteins
  • Recombinant Fusion Proteins
  • Transcription Factors, TFII
  • Green Fluorescent Proteins
  • Transcription Factor TFIIH
  • DNA
  • RNA Polymerase II
  • RNA Polymerase I