Detection of guanine-C8-2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine adduct as a single spot on thin-layer chromatography by modification of the 32P-postlabeling method.
N-(Deoxyguanosin-8-yl)-2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (dG-C8-PhIP) has been shown to be a major adduct in DNA of rats given [3H]PhIP. However, when DNA from organs of rats fed PhIP was analyzed by the 32P-postlabeling method under standard and adduct-intensification conditions, four adduct spots were observed, and 3',5'-pdGp-C8-PhIP was detected as a minor, not a major, adduct spot. Since the three other major adduct spots were suspected to be those of adducted di- or oligo-nucleotides, the 32P-labeled samples were further treated with nuclease P1 and phosphodiesterase I and found to yield only a single adduct spot. The material in this adduct spot was confirmed to be 5'-pdG-C8-PhIP. Thus, using this newly modified 32P-postlabeling method, dG-C8-PhIP was detected as a major adduct in DNA of rats given PhIP.
Fukutome
K
K
Carcinogenesis Division, National Cancer Center Research Institute, Tokyo.
Ochiai
M
M
Wakabayashi
K
K
Watanabe
S
S
Sugimura
T
T
Nagao
M
M
D000818:Animals; D001345:Autoradiography / Q000379:methods; D002273:Carcinogens / Q000378:metabolism*; D002855:Chromatography, Thin Layer; D004247:DNA / Q000378:metabolism*; D003849:Deoxyguanosine / Q000031:analogs & derivatives* / Q000032:analysis / Q000737:chemistry / Q000302:isolation & purification; D007093:Imidazoles / Q000032:analysis* / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism* / Q000633:toxicity; D008168:Lung / Q000187:drug effects; D008297:Male; D009153:Mutagens / Q000378:metabolism*; D010761:Phosphorus Radioisotopes; D051381:Rats; D011916:Rats, Inbred F344
D002273:Carcinogens; D007093:Imidazoles; D009153:Mutagens; D010761:Phosphorus Radioisotopes; C078255:N-(deoxyguanosin-8-yl)-2-amino-1-methyl-6-phenylimidazo(4,5-b)pyridine; D004247:DNA; C049584:2-amino-1-methyl-6-phenylimidazo(4,5-b)pyridine; D003849:Deoxyguanosine