Analysis of 8-hydroxyguanine in rat kidney genomic DNA after administration of a renal carcinogen, ferric nitrilotriacetate.
The frequency of oxidative base damage, such as 8-hydroxyguanine (8-OH-Gua), was determined at the nucleotide level of resolution using the ligation-mediated PCR technique. Administration of a renal carcinogen, ferric nitrilotriacetate (Fe-NTA), is known to induce oxidative stress and subsequent formation of 8-OH-Gua in the rat kidney. Whole genomic DNA was isolated from the rat kidney after or without Fe-NTA treatment and then cleaved with hot piperidine. In order to assess the frequency of 8-OH-Gua formation, we chose three genes, the tumor suppressor gene p53, the heat shock protein 70 (HSP70-1) gene and the Na,K-ATPase alpha1 subunit gene. No alteration in the cleavage profile was observed in the p53 and HSP70 genes after Fe-NTA treatment. In the case of the p53 gene, a low incidence of point mutations has been observed in this carcinogenesis system. On the other hand, time-dependent alterations, corresponding to the time course of overall 8-OH-Gua formation and repair, were detected in the promoter region of the Na,K-ATPase alpha1 subunit gene. GpG and GpGpG in specific regions seem to be hotspots for the formation of 8-OH-Gua. These results were confirmed by formamidopyrimidine-DNA glycosylase-dependent DNA cleavage patterns. Thus, oxidative base damage, such as 8-OH-Gua, was not distributed uniformly along the whole genome, but seemed to be restricted to particular genes and regions.
Nomoto
M
M
Department of Molecular Biology, School of Medicine, University of Occupational and Environmental Health Japan, Kitakyushu. m-nomoto@mail.med.uoeh-u.ac.jp
Yamaguchi
R
R
Kawamura
M
M
Kohno
K
K
Kasai
H
H
D000818:Animals; D001483:Base Sequence; D002273:Carcinogens / Q000009:adverse effects*; D004247:DNA / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D004249:DNA Damage; D005290:Ferric Compounds / Q000009:adverse effects*; D006147:Guanine / Q000031:analogs & derivatives* / Q000032:analysis / Q000378:metabolism; D018840:HSP70 Heat-Shock Proteins / Q000187:drug effects / Q000235:genetics; D007668:Kidney / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D008969:Molecular Sequence Data; D009571:Nitrilotriacetic Acid / Q000009:adverse effects / Q000031:analogs & derivatives*; D010880:Piperidines / Q000494:pharmacology; D015800:Protozoan Proteins / Q000187:drug effects / Q000235:genetics; D051381:Rats; D017208:Rats, Wistar; D000254:Sodium-Potassium-Exchanging ATPase / Q000187:drug effects / Q000235:genetics; D016159:Tumor Suppressor Protein p53 / Q000187:drug effects / Q000235:genetics
D002273:Carcinogens; D005290:Ferric Compounds; D018840:HSP70 Heat-Shock Proteins; D010880:Piperidines; D015800:Protozoan Proteins; D016159:Tumor Suppressor Protein p53; C081884:heat-shock protein 70.1; C024829:8-hydroxyguanine; D006147:Guanine; C032727:piperidine; D004247:DNA; D000254:Sodium-Potassium-Exchanging ATPase; D009571:Nitrilotriacetic Acid; C020326:ferric nitrilotriacetate