Cisplatin-modified DNA-binding proteins in a nuclear extract of rat-liver cells.
A mobility shift DNA-binding assay showed that cisplatin-modified DNA-binding proteins are present in the nuclear extract of rat-liver cells (Ac2F cells). The major binding proteins of 22.5, 23, 96.5 and 112 kDa were identified in vitro. The binding activity of the 23 kDa protein was markedly enhanced in the cells that were cultured in the presence of cisplatin, and was inhibited by addition of cycloheximide to the culture. Our previous work [Hibino et al. (1994) Biochem. Biophys. Res. Commun. 202, 749-756] has shown that an Mg(2+)-dependent endo-exonuclease activity endogenous to Ac2F-cell nuclei is enhanced in the presence of cisplatin. Thus, the results of the present study imply that specific binding of the nuclear proteins to cisplatin-DNA lesions in rat-liver cells is involved in the mechanism of enhancement of this nuclease activity.
Hibino
Y
Y
Division of Cell Biology, Faculty of Pharmaceutical Sciences, Toyama Medical & Pharmaceutical University, Japan.
Kusashio
E
E
Sugano
N
N
D000818:Animals; D002460:Cell Line; D002945:Cisplatin / Q000378:metabolism* / Q000494:pharmacology; D003513:Cycloheximide / Q000494:pharmacology; D004268:DNA-Binding Proteins / Q000378:metabolism*; D004336:Drug Antagonism; D008099:Liver / Q000378:metabolism*; D051381:Rats
D004268:DNA-Binding Proteins; D003513:Cycloheximide; D002945:Cisplatin