4ERN

Crystal structure of the C-terminal domain of human XPB/ERCC-3 excision repair protein at 1.80 A

Summary for 4ERN

• Entry DOI: 10.2210/pdb4ern/pdb
• Related: 2FWR 2FZL
• Descriptor: TFIIH basal transcription factor complex helicase XPB subunit (2 entities in total)
• Functional Keywords: helicase domain 2, general transcription factor tfiih, nucleotide excision repair, transcription coupled repair, basal transcription, nucleus, hydrolase
• Biological source: Homo sapiens (human)
• Cellular location: Nucleus: P19447
• Total number of polymer chains: 1
• Total formula weight: 33420.20

Authors

Hilario, E.,Li, Y.,Fan, L. (deposition date: 2012-04-20, release date: 2013-01-30, Last modification date: 2023-09-13)

Primary citation

Hilario, E.,Li, Y.,Nobumori, Y.,Liu, X.,Fan, L.
Structure of the C-terminal half of human XPB helicase and the impact of the disease-causing mutation XP11BE.
Acta Crystallogr.,Sect.D, 69:237-246, 2013

PubMed Abstract: XPB is a DNA-dependent helicase and a subunit of the TFIIH complex required for both transcription and DNA repair. XPB contains four domains: an N-terminal domain, two conserved helicase domains (HD1 and HD2) and a C-terminal extension. The C-terminal extension is important for DNA repair since the phosphorylation of Ser751 inhibits 5'-incision by ERCC1-XPF endonuclease. A disease-causing frameshift mutation (XP11BE) that changes the last 42 amino acids of XPB causes manifestations including impaired DNA repair and deficient transcription. Here, the crystal structure of the C-terminal half of XPB (residues 494-782) is reported at 1.8 Å resolution. The structure contained the conserved XPB HD2 and a C-terminal extension which shares structural similarity with RIG-I, leading to a structural model of the XPF-XPB-DNA complex for 5' incision during DNA repair. A mutation mimicking the XP11BE mutation produced the much less soluble mutant XPBm(494-781). Western blotting results confirmed that the intracellular levels of XPB and other TFIIH subunits in XP11BE patient cells were much lower than those from the healthy parents. Together, these results indicate that the XP11BE mutation not only divests the XPF-interaction motif, impairing DNA repair, but also reduces XPB solubility, leading to a lower intracellular level of TFIIH and deficient transcription.

PubMed: 23385459
DOI: 10.1107/S0907444912045040

Experimental method

X-RAY DIFFRACTION (1.8 Å)