title: Spectrum of cis-diamminedichloroplatinum(II)-induced mutations in a shuttle vector propagated in human cells.
abstract: The supF gene of the shuttle vector pZ189 was used as a target for the study of mutations induced by cis-diamminedichloroplatinum(II) (cis-DDP). Normal human repair-proficient fibroblasts and cis-DDP repair-deficient xeroderma pigmentosum (XP) cells were used as host cells to study the effect of cis-DDP on the inhibition of shuttle vector replication and mutagenesis. Transfection of cis-DDP-treated pZ189 into normal and XP cell lines resulted in a marked increase in the mutation frequency and a decrease in the replication efficiency of the vector. However, these effects were much greater for the plasmid propagated in XP cells. Atomic absorption spectroscopy showed that six to eight Pt-DNA adducts per plasmid were necessary to inhibit plasmid replication by 50% in normal cells. In contrast, only one to two Pt-DNA adducts were necessary to inhibit replication of the plasmid by 50% in XP cells. Analysis of mutation sites demonstrated that cis-DDP treatment resulted primarily in single and double mutations separated by one base and limited to a few locations within the 85-bp mature tRNA. Propagation of the cis-DDP-treated vector in either normal or XP cells led to predominantly transversion mutations at AGA, AGG, and GAG sites and a cis-DDP-associated deletion of 174 bp. Although mutations occurred at target sites for cis-DDP adduct formation, there was no correlation between sites of mutation and the most frequent sites of adduct formation.
authors.affiliation: Charles A. Dana Research Institute, Harvard-Thorndike Laboratory of Beth Israel Hospital, Boston, MA 02215.
authors.forename: G J
authors.initials: GJ
authors.lastname: Bubley
authors.forename: B P
authors.initials: BP
authors.lastname: Ashburner
authors.forename: B A
authors.initials: BA
authors.lastname: Teicher
mesh_terms: D001483:Base Sequence; D002478:Cells, Cultured; D002945:Cisplatin / Q000633:toxicity*; D004249:DNA Damage; D004260:DNA Repair; D004261:DNA Replication; D016153:Genes, Suppressor; D005822:Genetic Vectors; D006801:Humans; D066298:In Vitro Techniques; D008969:Molecular Sequence Data; D016296:Mutagenesis; D009153:Mutagens; D019384:Nucleic Acid Synthesis Inhibitors; D009841:Oligonucleotides / Q000737:chemistry; D010957:Plasmids
chemical_list: D009153:Mutagens; D019384:Nucleic Acid Synthesis Inhibitors; D009841:Oligonucleotides; D002945:Cisplatin