Partial N-terminal amino acid sequences of polypeptides p14 and p12 of encephalomyocarditis virus are identical and correspond to the N-terminus of the viral polyprotein.
Our previous data suggested that translation in an EMC virus RNA-programmed cell-free system from Krebs-2 cells is initiated predominantly at a single site and that the earliest amino acid sequences synthesized correspond to non-structural 'leader' polypeptides p14 and p12 [(1982) FEBS Lett. 141, 153-156]. Here, polypeptides p14 and p12 were labelled in vitro by tritiated amino acids, isolated and subjected to automated Edman degradation. Both polypeptides (after the loss of the N-terminal methionine) were shown to contain alanine in position 1 and glutamic acid in positions 5 and 7. These and other data demonstrate that p14 and p12 share a common N-terminal sequence. This sequence coincides precisely with the N-terminus of EMC virus polyprotein sequence deduced from the primary structure of the viral genome [(1984) Nucleic Acids Res., in press]. Thus, the single initiation site operating in our translation system corresponds to the start of the polyprotein molecule.
D000595:Amino Acid Sequence; D001483:Base Sequence; D003062:Codon; D004686:Encephalomyocarditis virus / Q000235:genetics*; D005814:Genes, Viral; D010442:Peptide Chain Initiation, Translational; D010446:Peptide Fragments; D014176:Protein Biosynthesis; D012367:RNA, Viral / Q000378:metabolism*; D014764:Viral Proteins / Q000235:genetics*
D003062:Codon; D010446:Peptide Fragments; D012367:RNA, Viral; D014764:Viral Proteins