title: UV-induced ubiquitylation of XPC protein mediated by UV-DDB-ubiquitin ligase complex.
abstract: The xeroderma pigmentosum group C (XPC) protein complex plays a key role in recognizing DNA damage throughout the genome for mammalian nucleotide excision repair (NER). Ultraviolet light (UV)-damaged DNA binding protein (UV-DDB) is another complex that appears to be involved in the recognition of NER-inducing damage, although the precise role it plays and its relationship to XPC remain to be elucidated. Here we show that XPC undergoes reversible ubiquitylation upon UV irradiation of cells and that this depends on the presence of functional UV-DDB activity. XPC and UV-DDB were demonstrated to interact physically, and both are polyubiquitylated by the recombinant UV-DDB-ubiquitin ligase complex. The polyubiquitylation altered the DNA binding properties of XPC and UV-DDB and appeared to be required for cell-free NER of UV-induced (6-4) photoproducts specifically when UV-DDB was bound to the lesion. Our results strongly suggest that ubiquitylation plays a critical role in the transfer of the UV-induced lesion from UV-DDB to XPC.
authors.affiliation: Cellular Physiology Laboratory, RIKEN Discovery Research Institute, Japan Science and Technology Agency, Wako, Saitama 351-0198, Japan. sugasawa@riken.jp
authors.forename: Kaoru
authors.initials: K
authors.lastname: Sugasawa
authors.forename: Yuki
authors.initials: Y
authors.lastname: Okuda
authors.forename: Masafumi
authors.initials: M
authors.lastname: Saijo
authors.forename: Ryotaro
authors.initials: R
authors.lastname: Nishi
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Matsuda
authors.forename: Gilbert
authors.initials: G
authors.lastname: Chu
authors.forename: Toshio
authors.initials: T
authors.lastname: Mori
authors.forename: Shigenori
authors.initials: S
authors.lastname: Iwai
authors.forename: Keiji
authors.initials: K
authors.lastname: Tanaka
authors.forename: Kiyoji
authors.initials: K
authors.lastname: Tanaka
authors.forename: Fumio
authors.initials: F
authors.lastname: Hanaoka
mesh_terms: D002460:Cell Line; D002461:Cell Line, Transformed; D045744:Cell Line, Tumor; D002474:Cell-Free System / Q000378:metabolism; D004247:DNA / Q000378:metabolism; D004260:DNA Repair; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D008954:Models, Biological; D009154:Mutation; D011485:Protein Binding; D011499:Protein Processing, Post-Translational / Q000528:radiation effects; D011740:Pyrimidine Dimers / Q000378:metabolism; D025801:Ubiquitin / Q000378:metabolism*; D043743:Ubiquitin-Protein Ligase Complexes / Q000378:metabolism*; D044767:Ubiquitin-Protein Ligases / Q000378:metabolism; D014466:Ultraviolet Rays
chemical_list: C117669:DDB2 protein, human; D004268:DNA-Binding Proteins; D011740:Pyrimidine Dimers; D025801:Ubiquitin; C058406:pyrimidine-pyrimidone dimer; C086984:XPC protein, human; D004247:DNA; D043743:Ubiquitin-Protein Ligase Complexes; D044767:Ubiquitin-Protein Ligases