title: Resolution of the discrepancy between a gene translation--termination codon and the deduced sequence for release of the encoded polypeptide.
abstract: The translation-termination codon of the synthetase gene of the RNA phage MS2 has been determined, by nucleotide sequencing and suppression studies in vitro, to be UAG. However in one of the only two studies on the signals for polypeptide chain release at the end of genes, Capecchi and Klein [(1970) Nature (Lond.) 226, 1029-1033] deduced that the synthetase of an almost identical phage, R17, is released at UAA. Here we show that under certain conditions the synthetase is released at the UAG terminator but that this UAG is especially prone to read-through with resulting release at the downstream UAA codon. The possible significance of the UAG being in a context prone to leakiness is discussed but is unresolved.
mesh_terms: D001345:Autoradiography; D001483:Base Sequence; D002499:Centrifugation, Density Gradient; D003062:Codon; D010443:Peptide Chain Termination, Translational; D014176:Protein Biosynthesis; D012317:RNA Phages / Q000235:genetics*; D012333:RNA, Messenger
chemical_list: D003062:Codon; D012333:RNA, Messenger