The intricate network between the p34 and p44 subunits is central to the activity of the transcription/DNA repair factor TFIIH

Nucleic Acids Res. 2017 Oct 13;45(18):10872-10883. doi: 10.1093/nar/gkx743.


The general transcription factor IIH (TFIIH) is a multi-protein complex and its 10 subunits are engaged in an intricate protein-protein interaction network critical for the regulation of its transcription and DNA repair activities that are so far little understood on a molecular level. In this study, we focused on the p44 and the p34 subunits, which are central for the structural integrity of core-TFIIH. We solved crystal structures of a complex formed by the p34 N-terminal vWA and p44 C-terminal zinc binding domains from Chaetomium thermophilum and from Homo sapiens. Intriguingly, our functional analyses clearly revealed the presence of a second interface located in the C-terminal zinc binding region of p34, which can rescue a disrupted interaction between the p34 vWA and the p44 RING domain. In addition, we demonstrate that the C-terminal zinc binding domain of p34 assumes a central role with respect to the stability and function of TFIIH. Our data reveal a redundant interaction network within core-TFIIH, which may serve to minimize the susceptibility to mutational impairment. This provides first insights why so far no mutations in the p34 or p44 TFIIH-core subunits have been identified that would lead to the hallmark nucleotide excision repair syndromes xeroderma pigmentosum or trichothiodystrophy.

MeSH terms

  • Chaetomium / enzymology
  • Fungal Proteins / chemistry
  • Humans
  • Models, Molecular
  • Mutation
  • Protein Interaction Domains and Motifs
  • Protein Subunits / chemistry
  • Transcription Factor TFIIH / chemistry*
  • Transcription Factor TFIIH / genetics


  • Fungal Proteins
  • Protein Subunits
  • p34 TFIIH subunit, human
  • p44 TFIIH subunit, human
  • Transcription Factor TFIIH