Source:http://linkedlifedata.com/resource/umls/id/C1333232
NCI: XPG-Complementing Protein, encoded by the ERCC5 gene is involved in transcription-coupled repair of UV-induced DNA damage. It is a single-strand specific DNA endonuclease that nicks damaged DNA 3-prime to the lesion in nucleotide excision repair as a result of the combined action of the XPB helicase and XPD helicase following sequential assembly of repair proteins at the DNA damage site. In addition, it associates with CSA, CSB, or both proteins at the transcriptional pause sites to facilitate the resumption of transcript elongation without aborting the associated nascent transcript by pushing the stalled RNA polymerase II either forward or backward not only from the damaged site but also from some natural transcription pause sites. Mutational inactivation of XPG causes Cockayne syndrome, which is characterized by severe growth defects, mental retardation, and cachexia. (from OMIM 133530, LocusLink 2073 and NCI)