The fidelity of DNA synthesis by yeast DNA polymerase zeta alone and with accessory proteins.
DNA polymerase zeta (pol zeta) participates in several DNA transactions in eukaryotic cells that increase spontaneous and damage-induced mutagenesis. To better understand this central role in mutagenesis in vivo, here we report the fidelity of DNA synthesis in vitro by yeast pol zeta alone and with RFC, PCNA and RPA. Overall, the accessory proteins have little effect on the fidelity of pol zeta. Pol zeta is relatively accurate for single base insertion/deletion errors. However, the average base substitution fidelity of pol zeta is substantially lower than that of homologous B family pols alpha, delta and epsilon. Pol zeta is particularly error prone for substitutions in specific sequence contexts and generates multiple single base errors clustered in short patches at a rate that is unprecedented in comparison with other polymerases. The unique error specificity of pol zeta in vitro is consistent with Pol zeta-dependent mutagenic specificity reported in vivo. This fact, combined with the high rate of single base substitution errors and complex mutations observed here, indicates that pol zeta contributes to mutagenesis in vivo not only by extending mismatches made by other polymerases, but also by directly generating its own mismatches and then extending them.
Zhong
Xuejun
X
Laboratory of Molecular Genetics and Laboratory of Structural Biology, National Institute of Environmental Health Sciences, NIH, DHHS, Research Triangle Park, NC 27709, USA.
Garg
Parie
P
Stith
Carrie M
CM
Nick McElhinny
Stephanie A
SA
Kissling
Grace E
GE
Burgers
Peter M J
PM
Kunkel
Thomas A
TA
D001483:Base Sequence; D004247:DNA / Q000096:biosynthesis* / Q000737:chemistry; D004259:DNA-Directed DNA Polymerase / Q000378:metabolism*; D016296:Mutagenesis; D009154:Mutation; D009711:Nucleotides / Q000378:metabolism; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism; D051716:Replication Protein A / Q000378:metabolism*; D051818:Replication Protein C / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism*; D001616:beta-Galactosidase / Q000235:genetics
D009711:Nucleotides; D018809:Proliferating Cell Nuclear Antigen; C092219:REV7 protein, S cerevisiae; D051716:Replication Protein A; D029701:Saccharomyces cerevisiae Proteins; D004247:DNA; D004259:DNA-Directed DNA Polymerase; C092602:REV3 protein, S cerevisiae; D001616:beta-Galactosidase; D051818:Replication Protein C