Bax1 is a novel endonuclease: implications for archaeal nucleotide excision repair.

ABSTRACT: The helicases XPB and XPD are part of the TFIIH complex, which mediates transcription initiation as well as eukaryotic nucleotide excision repair (NER). Although there is no TFIIH complex present in archaea, most species contain both XPB and XPD and serve as a model for their eukaryotic homologs. Recently, a novel binding partner for XPB, Bax1 (binds archeal XPB), was identified in archaea. To gain insights into its role in NER, Bax1 from Thermoplasma acidophilum was characterized. We identified Bax1 as a novel Mg(2+)-dependent structure-specific endonuclease recognizing DNA containing a 3' overhang. Incision assays conducted with DNA substrates providing different lengths of the 3' overhang indicate that Bax1 specifically incises DNA in the single-stranded region of the 3' overhang 4-6 nu

SUBMITTER: Roth HM 

PROVIDER: S-EPMC2781640 | biostudies-literature | 2009 Nov

REPOSITORIES: biostudies-literature