title: Nucleotide excision repair in human cells: fate of the excised oligonucleotide carrying DNA damage in vivo.
abstract: Nucleotide excision repair is the sole mechanism for removing the major UV photoproducts from genomic DNA in human cells. In vitro with human cell-free extract or purified excision repair factors, the damage is removed from naked DNA or nucleosomes in the form of 24- to 32-nucleotide-long oligomers (nominal 30-mer) by dual incisions. Whether the DNA damage is removed from chromatin in vivo in a similar manner and what the fate of the excised oligomer was has not been known previously. Here, we demonstrate that dual incisions occur in vivo identical to the in vitro reaction. Further, we show that transcription-coupled repair, which operates in the absence of the XPC protein, also generates the nominal 30-mer in UV-irradiated XP-C mutant cells. Finally, we report that the excised 30-mer is released from the chromatin in complex with the repair factors TFIIH and XPG. Taken together, our results show the congruence of in vivo and in vitro data on nucleotide excision repair in humans.
authors.affiliation: From the Department of Biochemistry and Biophysics, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599-7260 and.
authors.forename: Jinchuan
authors.initials: J
authors.lastname: Hu
authors.affiliation: From the Department of Biochemistry and Biophysics, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599-7260 and; the Center for Bioanalysis, Department of Metrology for Quality of Life, Korea Research Institute of Standards and Science, Daejeon 305-340, South Korea.
authors.forename: Jun-Hyuk
authors.initials: JH
authors.lastname: Choi
authors.affiliation: From the Department of Biochemistry and Biophysics, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599-7260 and.
authors.forename: Shobhan
authors.initials: S
authors.lastname: Gaddameedhi
authors.affiliation: From the Department of Biochemistry and Biophysics, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599-7260 and.
authors.forename: Michael G
authors.initials: MG
authors.lastname: Kemp
authors.affiliation: From the Department of Biochemistry and Biophysics, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599-7260 and.
authors.forename: Joyce T
authors.initials: JT
authors.lastname: Reardon
authors.affiliation: From the Department of Biochemistry and Biophysics, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599-7260 and.
authors.forename: Aziz
authors.initials: A
authors.lastname: Sancar
mesh_terms: D000818:Animals; D002460:Cell Line; D004249:DNA Damage; D004260:DNA Repair / Q000528:radiation effects; D004268:DNA-Binding Proteins / Q000378:metabolism; D006801:Humans; D008954:Models, Biological; D009154:Mutation / Q000235:genetics; D009841:Oligonucleotides / Q000378:metabolism*; D011740:Pyrimidine Dimers / Q000378:metabolism; D051758:Transcription Factor TFIIH / Q000378:metabolism; D014158:Transcription, Genetic / Q000528:radiation effects; D014466:Ultraviolet Rays
chemical_list: D004268:DNA-Binding Proteins; D009841:Oligonucleotides; D011740:Pyrimidine Dimers; D051758:Transcription Factor TFIIH
keywords: Chromatin; DNA Binding Protein; DNA Damage; DNA Nucleotide Excision Repair; DNA Repair; Dual Incision; Pyrimidine Dimers; TFIIH; Transcription-coupled Repair