title: Enzymatic switching for efficient and accurate translesion DNA replication.
abstract: When cyclobutane pyrimidine dimers stall DNA replication by DNA polymerase (Pol) delta or epsilon, a switch occurs to allow translesion synthesis by DNA polymerase eta, followed by another switch that allows normal replication to resume. In the present study, we investigate these switches using Saccharomyces cerevisiae Pol delta, Pol epsilon and Pol eta and a series of matched and mismatched primer templates that mimic each incorporation needed to completely bypass a cis-syn thymine-thymine (TT) dimer. We report a complementary pattern of substrate use indicating that enzymatic switching involving localized translesion synthesis by Pol eta and mismatch excision and polymerization by a major replicative polymerase can account for the efficient and accurate dimer bypass known to suppress sunlight-induced mutagenesis and skin cancer.
authors.affiliation: Laboratory of Molecular Genetics and Laboratory of Structural Biology, National Institute of Environmental Health Sciences, NIH, DHHS, Research Triangle Park, NC 27709, USA.
authors.forename: Scott D
authors.initials: SD
authors.lastname: McCulloch
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Kokoska
authors.forename: Olga
authors.initials: O
authors.lastname: Chilkova
authors.forename: Carrie M
authors.initials: CM
authors.lastname: Welch
authors.forename: Erik
authors.initials: E
authors.lastname: Johansson
authors.forename: Peter M J
authors.initials: PM
authors.lastname: Burgers
authors.forename: Thomas A
authors.initials: TA
authors.lastname: Kunkel
mesh_terms: D020137:Base Pair Mismatch; D004249:DNA Damage; D004257:DNA Polymerase II / Q000378:metabolism; D004258:DNA Polymerase III / Q000378:metabolism; D004261:DNA Replication; D004259:DNA-Directed DNA Polymerase / Q000378:metabolism*; D005090:Exodeoxyribonucleases / Q000378:metabolism; D008957:Models, Genetic; D011740:Pyrimidine Dimers / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000201:enzymology; D000099270:Y-Family DNA Polymerases
chemical_list: D004257:DNA Polymerase II; D004258:DNA Polymerase III; D004259:DNA-Directed DNA Polymerase; D005090:Exodeoxyribonucleases; D011740:Pyrimidine Dimers; C112338:Rad30 protein; D000099270:Y-Family DNA Polymerases