title: Synthesis of an ochre suppressor tRNA gene and expression in mammalian cells.
abstract: We have used site-specific mutagenesis to change the anticodon of a Xenopus laevis tyrosine tRNA gene so that it would recognize ochre codons. This tRNA gene is expressed when amplified in monkey cells as part of a SV40 recombinant and efficiently suppresses termination at both the ochre codon separating the adenovirus 2 hexon gene from a 23-kd downstream gene and the ochre codon at the end of the NS1 gene of influenza virus A/Tex/1/68. Termination at an amber codon of a NS1 gene of another influenza virus strain was not suppressed by the (Su+) ochre gene suggesting that in mammalian cells amber codons are not recognized by ochre suppressor tRNAs. Finally, microinjection into mammalian cells of both (Su+) ochre tRNA genes and selectible genes containing ochre nonsense mutations gives rise to colonies under selective conditions. We conclude that it should be possible to isolate a wide assortment of mammalian cell lines with ochre suppressor activity.
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D002522:Chlorocebus aethiops; D003001:Cloning, Molecular; D003062:Codon; D004262:DNA Restriction Enzymes; D005813:Genes, Synthetic; D007668:Kidney; D009154:Mutation; D009690:Nucleic Acid Conformation; D012346:RNA, Transfer, Amino Acyl / Q000235:genetics*; D013539:Simian virus 40 / Q000235:genetics; D013489:Suppression, Genetic; D014158:Transcription, Genetic; D014981:Xenopus
chemical_list: D003062:Codon; D012346:RNA, Transfer, Amino Acyl; D004262:DNA Restriction Enzymes