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Atomic Force Microscopy Investigations of DNA Lesion Recognition in Nucleotide Excision Repair
Published on: May 24, 2017
Mutations in the XPD helicase gene result in XP and TTD phenotypes, preventing interaction between XPD and the p44
F Coin1, J C Marinoni, C Rodolfo
1Institut de Génétique et de Biologie Moléculaire et Cellulaire, CNRS/INSERM/ULP, B.P.163, Illkirch, C.U. de Strasbourg, France.
Abstract:
In most cases, xeroderma pigmentosum group D (XP-D) and trichothiodystrophy (TTD) patients carry mutations in the carboxy-terminal domain of the evolutionarily conserved helicase XPD, which is one of the subunits of the transcription/repair factor TFIIH (refs 1,2). In this study, we demonstrate that XPD interacts specifically with p44, another subunit of TFIIH, and that this interaction results in the stimulation of 5'-->3' helicase activity. Mutations in the XPD C-terminal domain, as found in most patients, prevent the interaction with p44, thus explaining the decrease in XPD helicase activity and the nucleotide excision repair (NER) defect.
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