title: XPB: An unconventional SF2 DNA helicase.
abstract: XPB is a 3'-5' DNA helicase belonging to the superfamily 2 (SF2) of helicases. XPB is an essential core subunit of the eukaryotic basal transcription factor complex TFIIH which plays a dual role in transcription and DNA repair: 1) to facilitate the melting of the promoter during the initiation of RNA polymerase II transcription; 2) to unwind double stranded DNA (dsDNA) around a DNA lesion during nucleotide excision repair (NER). NER is a highly versatile DNA repair process which is able to remove a broad spectrum of structurally unrelated DNA helix-distorting lesions. The importance of a fully functional XPB is clearly illustrated by the severe clinical consequences associated with inherited defects in XPB including UV-hypersensitive syndromes xeroderma pigmentosum (XP), Cockayne syndrome (CS), combined XP and CS (XP/CS), and trichothiodystrophy (TTD). Here we discuss the structure and function of XPB in NER as well as the impact of a disease mutation in XP11BE patients with XP/CS complex manifestations.
authors: 900 University Ave, Biochemistry Department, University of California, Riverside, CA 92521, USA. Electronic address: lifan@ucr.edu.
authors: Li
authors: L
authors: Fan
authors: 900 University Ave, Biochemistry Department, University of California, Riverside, CA 92521, USA.
authors: Kevin T
authors: KT
authors: DuPrez
mesh_terms: D004247:DNA / Q000737:chemistry* / Q000235:genetics*; D004249:DNA Damage / Q000235:genetics*; D004265:DNA Helicases / Q000737:chemistry* / Q000235:genetics*; D004260:DNA Repair / Q000235:genetics; D049914:DNA Repair-Deficiency Disorders / Q000235:genetics*; D004789:Enzyme Activation; D006801:Humans
chemical_list: D004247:DNA; D004265:DNA Helicases
keywords: ERCC3; Transcription-coupled repair (TCR); XPB; helicase; nucleotide excision repair (NER); transcription factor IIH (TFIIH)