Structural basis of human transcription-DNA repair coupling

Nature. 2021 Oct;598(7880):368-372. doi: 10.1038/s41586-021-03906-4. Epub 2021 Sep 15.

Abstract

Transcription-coupled DNA repair removes bulky DNA lesions from the genome1,2 and protects cells against ultraviolet (UV) irradiation3. Transcription-coupled DNA repair begins when RNA polymerase II (Pol II) stalls at a DNA lesion and recruits the Cockayne syndrome protein CSB, the E3 ubiquitin ligase, CRL4CSA and UV-stimulated scaffold protein A (UVSSA)3. Here we provide five high-resolution structures of Pol II transcription complexes containing human transcription-coupled DNA repair factors and the elongation factors PAF1 complex (PAF) and SPT6. Together with biochemical and published3,4 data, the structures provide a model for transcription-repair coupling. Stalling of Pol II at a DNA lesion triggers replacement of the elongation factor DSIF by CSB, which binds to PAF and moves upstream DNA to SPT6. The resulting elongation complex, ECTCR, uses the CSA-stimulated translocase activity of CSB to pull on upstream DNA and push Pol II forward. If the lesion cannot be bypassed, CRL4CSA spans over the Pol II clamp and ubiquitylates the RPB1 residue K1268, enabling recruitment of TFIIH to UVSSA and DNA repair. Conformational changes in CRL4CSA lead to ubiquitylation of CSB and to release of transcription-coupled DNA repair factors before transcription may continue over repaired DNA.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Carrier Proteins / chemistry
  • Carrier Proteins / metabolism
  • Carrier Proteins / ultrastructure
  • Cryoelectron Microscopy*
  • DNA Helicases / chemistry
  • DNA Helicases / metabolism
  • DNA Helicases / ultrastructure
  • DNA Repair Enzymes / chemistry
  • DNA Repair Enzymes / metabolism
  • DNA Repair Enzymes / ultrastructure
  • DNA Repair*
  • DNA-Binding Proteins / chemistry
  • DNA-Binding Proteins / metabolism
  • DNA-Binding Proteins / ultrastructure
  • Humans
  • Models, Molecular
  • Multiprotein Complexes / chemistry*
  • Multiprotein Complexes / metabolism
  • Multiprotein Complexes / ultrastructure*
  • Poly-ADP-Ribose Binding Proteins / chemistry
  • Poly-ADP-Ribose Binding Proteins / metabolism
  • Poly-ADP-Ribose Binding Proteins / ultrastructure
  • RNA Polymerase II / chemistry*
  • RNA Polymerase II / metabolism
  • RNA Polymerase II / ultrastructure*
  • Transcription Elongation, Genetic
  • Transcription Factor TFIIH / chemistry
  • Transcription Factor TFIIH / metabolism
  • Transcription Factor TFIIH / ultrastructure
  • Transcription Factors / chemistry
  • Transcription Factors / metabolism
  • Transcription Factors / ultrastructure
  • Transcription, Genetic*
  • Ubiquitin-Protein Ligases / chemistry
  • Ubiquitin-Protein Ligases / metabolism
  • Ubiquitin-Protein Ligases / ultrastructure
  • Ubiquitination

Substances

  • Carrier Proteins
  • DDB1 protein, human
  • DNA-Binding Proteins
  • IL17RB protein, human
  • Multiprotein Complexes
  • PCLAF protein, human
  • Poly-ADP-Ribose Binding Proteins
  • SUPT6H protein, human
  • Transcription Factors
  • UVSSA protein, human
  • Transcription Factor TFIIH
  • Ubiquitin-Protein Ligases
  • RNA Polymerase II
  • DNA Helicases
  • ERCC6 protein, human
  • DNA Repair Enzymes