Introduction of UAG, UAA, and UGA Nonsense Mutations at a Specific Site in the Escherichia coli Chloramphenicol Acetyltransferase Gene: Use in Measurement of Amber, Ochre, and Opal Suppression in Mammalian Cells

We have used oligonucleotide-directed site-specific mutagenesis to convert serine codon 27 of the Escherichia coli chloramphenicol acetyltransferase (cat) gene to UAG, UAA, and UGA nonsense codons. The mutant cat genes, under transcriptional control of the Rous sarcoma virus long terminal repeat, were then introduced into mammalian cells by DNA transfection along with UAG, UAA, and UGA suppressor tRNA genes derived from a human serine tRNA. …