title: Characterization of a UGA-suppressing serine tRNA from Schizosaccharomyces pombe with the help of a new in vitro assay system for eukaryotic suppressor tRNAs.
abstract: Two different allele-specific suppressor mutants of the fission yeast Schizosaccharomyces pombe produce opal (UGA) suppressor tRNAs. This was shown by the use of a new in vitro assay for eukaryotic nonsense suppression: a wheat germ extract is programmed with rabbit globin mRNAs and the readthrough products are studied. alpha-Globin is elongated upon addition of ochre (UAA) suppressor tRNAs, whereas beta-globin yields a readthrough product with opal suppressor tRNAs. This simple and very sensitive assay allowed the purification of the opal suppressor tRNA from S. pombe strain sup3-e. The pure tRNA can be aminoacylated with serine; thus, we conclude that this suppressor tRNA inserts serine in response to the UGA termination codon of pure rabbit beta-globin mRNA.
mesh_terms: D000483:Alleles; D000818:Animals; D001203:Ascomycota / Q000378:metabolism*; D005914:Globins / Q000096:biosynthesis; D009154:Mutation; D010944:Plants / Q000378:metabolism; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000378:metabolism; D012343:RNA, Transfer / Q000235:genetics / Q000378:metabolism; D011817:Rabbits; D012568:Schizosaccharomyces / Q000235:genetics / Q000378:metabolism*; D012694:Serine; D013045:Species Specificity; D014908:Triticum / Q000378:metabolism
chemical_list: D012333:RNA, Messenger; D012694:Serine; D005914:Globins; D012343:RNA, Transfer