Roles of specialized DNA polymerases in mutagenesis by oxidized guanine.
To assess the involvement of specialized DNA polymerases in the mutagenesis induced by an oxidized form of dGTP, 8-hydroxy-2'-deoxyguanosine 5'-triphosphate (8-OH-dGTP, 7,8-dihydro-8-oxo-2'-deoxyguanosine 5'-triphosphate), shuttle plasmid DNA containing the supF gene and 8-OH-dGTP were introduced into human 293T cells in which specialized DNA polymerases were knocked-down by siRNAs. The knock-downs of DNA polymerases eta and zeta, and REV1 reduced the A:T-->C:G substitution mutations, suggesting that these DNA polymerases are involved in the misincorporation of 8-OH-dGTP opposite A. In contrast, the knock-down of DNA polymerase tau did not affect the mutations induced by 8-OH-dGTP. The decrease in the induced mutation frequency was more evident by double knock-downs of DNA pols eta plus zeta and REV1 plus DNA pol zeta (but not by that of DNA pol eta plus REV1), suggesting that REV1-DNA pol eta and DNA pol zeta work in different steps. These results indicate that specialized DNA polymerases are involved in the mutagenesis induced by 8-OH-dGTP.
Kamiya
Hiroyuki
H
Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan. hirokam@pharm.hokudai.ac.jp
Satou
Kazuya
K
Hori
Mika
M
Yamaguchi
Ayaka
A
Harashima
Hideyoshi
H
D002460:Cell Line; D004259:DNA-Directed DNA Polymerase / Q000502:physiology*; D003848:Deoxyguanine Nucleotides / Q000378:metabolism*; D055785:Gene Knockdown Techniques; D006801:Humans; D016296:Mutagenesis; D009687:Nuclear Proteins / Q000037:antagonists & inhibitors / Q000502:physiology*; D019384:Nucleic Acid Synthesis Inhibitors; D009713:Nucleotidyltransferases / Q000037:antagonists & inhibitors / Q000502:physiology*; D000099270:Y-Family DNA Polymerases
D004259:DNA-Directed DNA Polymerase; D003848:Deoxyguanine Nucleotides; D009687:Nuclear Proteins; D019384:Nucleic Acid Synthesis Inhibitors; D009713:Nucleotidyltransferases; C078206:8-oxodeoxyguanosine triphosphate; C425929:DNA polymerase zeta; C429004:REV1 protein, human; D000099270:Y-Family DNA Polymerases; C112338:Rad30 protein