Mechanism of translational coupling between coat protein and replicase genes of RNA bacteriophage MS2.
We have analyzed the molecular mechanism that makes translation of the MS2 replicase cistron dependent on the translation of the upstream coat cistron. Deletion mapping on cloned cDNA of the phage shows that the ribosomal binding site of the replicase cistron is masked by a long distance basepairing to an internal coat cistron region. Removal of the internal coat cistron region leads to uncoupled replicase synthesis. Our results confirm the model as originally proposed by Min Jou et al. (1). Activation of the replicase start is sensitive to the frequency of upstream translation, but never reaches the level of uncoupled replicase synthesis.
D001435:Bacteriophages / Q000235:genetics*; D002213:Capsid / Q000235:genetics*; D036022:Capsid Proteins; D002872:Chromosome Deletion; D005786:Gene Expression Regulation; D005796:Genes; D005814:Genes, Viral; D006860:Hydrogen Bonding; D009690:Nucleic Acid Conformation; D014176:Protein Biosynthesis; D012316:RNA Nucleotidyltransferases / Q000235:genetics*; D012328:RNA Viruses / Q000235:genetics*; D012367:RNA, Viral / Q000235:genetics*; D016601:RNA-Binding Proteins; D012324:RNA-Dependent RNA Polymerase / Q000235:genetics*; D012270:Ribosomes / Q000378:metabolism
D036022:Capsid Proteins; D012367:RNA, Viral; D016601:RNA-Binding Proteins; D012316:RNA Nucleotidyltransferases; D012324:RNA-Dependent RNA Polymerase