A repair system for 8-oxo-7,8-dihydrodeoxyguanine.
Active oxygen species can damage DNA and may play a role in aging and carcinogenesis. We have tested MutY glycosylase for activity on undamaged mispairs as well as mispairs formed with the oxidatively damaged substrates, 8-oxo-7,8-dihydrodeoxyguanine (GO) or 8-oxo-7,8-dihydrodeoxyadenine (AO). MutY acts as a glycosylase on four of the heteroduplexes tested, A/G, A/GO, A/C, and A/AO, removing the undamaged adenine from each substrate. Genetic data suggest that the primary substrate for MutY glycosylase in vivo is the A/GO mispair. We present biochemical evidence demonstrating that MutY glycosylase is an important part of a repair system that includes the MutM and MutT proteins. The GO repair system is dedicated to the repair of the oxidatively damaged guanine and the mutations it can induce.
Michaels
M L
ML
Department of Microbiology and Molecular Genetics, University of California, Los Angeles 90024.
Tchou
J
J
Grollman
A P
AP
Miller
J H
JH
D000080242:8-Hydroxy-2'-Deoxyguanosine / Q000031:analogs & derivatives; D001483:Base Sequence; D004249:DNA Damage; D045647:DNA Glycosylases; D004260:DNA Repair; D043382:DNA-Formamidopyrimidine Glycosylase; D006147:Guanine / Q000031:analogs & derivatives* / Q000378:metabolism; D008969:Molecular Sequence Data; D009699:N-Glycosyl Hydrolases / Q000235:genetics / Q000378:metabolism; D009692:Nucleic Acid Heteroduplexes; D013379:Substrate Specificity
D009692:Nucleic Acid Heteroduplexes; D006147:Guanine; C078307:8-oxo-7,8-dihydrodeoxyguanine; D000080242:8-Hydroxy-2'-Deoxyguanosine; D045647:DNA Glycosylases; D009699:N-Glycosyl Hydrolases; C061738:mutY adenine glycosylase; D043382:DNA-Formamidopyrimidine Glycosylase