title: Role of premature translational termination in the regulation of expression of the phi X174 lysis gene.
abstract: Expression of the phi X174 lysis (E) gene, a member of an overlapping gene pair, appears to depend on a frameshift-induced chain termination by ribosomes translating the upstream D gene. A -1 reading frameshift, possibly induced by misreading of an alanine codon as a doublet, causes ribosomes to terminate translation at two different sites, suggesting two modes of regulating expression of the E gene. One frameshift can cause translational termination at a stop codon(s) near the E gene ribosome binding site (RBS), resulting in reinitiation by ribosomes at the E gene RBS. Termination at a second site some 70 bases upstream from the E gene RBS, while too far away to allow ribosomal re-initiation at the E gene RBS, probably results in an unmasking of the message, allowing entry of a new ribosome at the E gene RBS.
mesh_terms: D010584:Bacteriophage phi X 174 / Q000235:genetics*; D001483:Base Sequence; D004279:DNA, Viral; D005786:Gene Expression Regulation; D005796:Genes; D005807:Genes, Overlapping; D005809:Genes, Regulator; D005814:Genes, Viral; D008969:Molecular Sequence Data; D014176:Protein Biosynthesis; D013728:Terminator Regions, Genetic
chemical_list: D004279:DNA, Viral