title: Affinity of yeast nucleotide excision repair factor 2, consisting of the Rad4 and Rad23 proteins, for ultraviolet damaged DNA.
abstract: Saccharomyces cerevisiae Rad4 and Rad23 proteins are required for the nucleotide excision repair of UV light-damaged DNA. Previous studies have indicated that these two DNA repair proteins are associated in a tight complex, which we refer to as nucleotide excision repair factor 2 (NEF2). In a reconstituted nucleotide excision repair reaction, incision of UV-damaged DNA is dependent on NEF2, indicating a role of NEF2 in an early step of the repair process. NEF2 does not, however, possess an enzymatic activity, and its function in the damage-specific incision reaction has not yet been defined. Here we use a DNA mobility shift assay to demonstrate that NEF2 binds specifically to UV-damaged DNA. Elimination of cyclobutane pyrimidine dimers from the UV-damaged DNA by enzymatic photoreactivation has little effect on the affinity of NEF2 for the DNA, suggesting that NEF2 recognizes the 6-(1, 2)-dihydro-2-oxo-4-pyrimidinyl)-5-methyl-2,4-(1H,3H)-pyrimidinedione photoproducts in the damaged DNA. These results highlight the intricacy of the DNA damage-demarcation reaction during nucleotide excision repair in eukaryotes.
authors.affiliation: Sealy Center for Molecular Science, University of Texas Medical Branch, Galveston, Texas 77555-1061, USA.
authors.forename: S N
authors.initials: SN
authors.lastname: Guzder
authors.forename: P
authors.initials: P
authors.lastname: Sung
authors.forename: L
authors.initials: L
authors.lastname: Prakash
authors.forename: S
authors.initials: S
authors.lastname: Prakash
mesh_terms: D002474:Cell-Free System; D004247:DNA / Q000378:metabolism / Q000528:radiation effects*; D004249:DNA Damage; D004260:DNA Repair; D004268:DNA-Binding Proteins / Q000378:metabolism*; D005656:Fungal Proteins / Q000378:metabolism*; D011485:Protein Binding; D011740:Pyrimidine Dimers / Q000378:metabolism; D012441:Saccharomyces cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D029702:Schizosaccharomyces pombe Proteins; D011503:Transglutaminases; D014466:Ultraviolet Rays
chemical_list: D004268:DNA-Binding Proteins; D005656:Fungal Proteins; D011740:Pyrimidine Dimers; C490846:RAD23 protein, S cerevisiae; C082463:RAD4 protein, S pombe; C490845:RHP23 protein, S pombe; D029701:Saccharomyces cerevisiae Proteins; D029702:Schizosaccharomyces pombe Proteins; C058406:pyrimidine-pyrimidone dimer; D004247:DNA; D011503:Transglutaminases