2-Hydroxy-2'-deoxyadenosine 5'-triphosphate enhances A.T --> C.G mutations caused by 8-hydroxy-2'-deoxyguanosine 5'-triphosphate by suppressing its degradation upon replication in a HeLa extract.
The coexistence effects of multiple kinds of oxidized deoxyribonucleotides were examined using an SV40 origin-dependent in vitro replication system with a HeLa extract. Oxidized dGTP and dATP, 8-hydroxy-2'-deoxyguanosine 5'-triphosphate (8-OH-dGTP) and 2-hydroxy-2'-deoxyadenosine 5'-triphosphate (2-OH-dATP), were used in this study. The mutation frequency synergistically increased when the two oxidized deoxyribonucleotides were together in the reaction. 2-OH-dATP enhanced the mutagenicity of 8-OH-dGTP, since the induced mutations were A.T --> C.G transversions. The contribution of the highly error-prone DNA polymerase eta was unlikely, since similar results were observed with an XP-V cell extract. The possible involvement of 2-hydroxyadenine in the complementary (template) strand was excluded on the basis of experiments using plasmids containing 2-hydroxyadenine as templates in the reactions with 8-OH-dGTP. 2-OH-dATP suppressed hydrolysis of 8-OH-dGTP, suggesting that the inhibition of the MTH1 protein played the major role in the enhancement. These results highlight the importance of specific hydrolysis of 8-OH-dGTP for the suppression of its induced mutation.
Satou
Kazuya
K
Faculty of Pharmaceutical Sciences, Hokkaido University, Kita-12, Nishi-6, Kita-ku, Sapporo 060-0812, Japan.
Kasai
Hiroshi
H
Masutani
Chikahide
C
Hanaoka
Fumio
F
Harashima
Hideyoshi
H
Kamiya
Hiroyuki
H
D000255:Adenosine Triphosphate / Q000031:analogs & derivatives* / Q000494:pharmacology*; D002457:Cell Extracts; D002474:Cell-Free System; D002478:Cells, Cultured; D004252:DNA Mutational Analysis; D045643:DNA Repair Enzymes / Q000187:drug effects* / Q000378:metabolism; D004261:DNA Replication / Q000187:drug effects*; D003848:Deoxyguanine Nucleotides; D006160:Guanosine Triphosphate / Q000031:analogs & derivatives* / Q000235:genetics; D006367:HeLa Cells; D006801:Humans; D008957:Models, Genetic; D016296:Mutagenesis / Q000187:drug effects*; D009154:Mutation; D010100:Oxygen / Q000378:metabolism; D010744:Phosphoric Monoester Hydrolases
C095141:2-hydroxydeoxyadenosine triphosphate; D002457:Cell Extracts; D003848:Deoxyguanine Nucleotides; D006160:Guanosine Triphosphate; C029603:deoxyguanosine triphosphate; D000255:Adenosine Triphosphate; D010744:Phosphoric Monoester Hydrolases; C078207:8-oxodGTPase; D045643:DNA Repair Enzymes; D010100:Oxygen