The genome-linked protein of picornaviruses. VI. The 5'-terminal protein of poliovirus type 2RNA is covalently linked to a nonanucleotide identical to that of poliovirus type 1 RNA.

: Digestion of poliovirus type 2[32P]-RNA with enzymes and analysis of the products by column chromatography and paper electrophoresis provides evidence that the RNA is covalently linked to a small, basic protein, VPg, via a 5'-terminal pU residue. Digestion of the RNA with proteinase K followed by labeling of the peptidyl-RNA with the Bolton and Hunter reagent [iodinated 3-(4-hydroxyphenyl)propionic acid N-hydroxysuccinimide ester] yields 5'-labeled material suitable for rapid sequencing. The 5'-terminal sequence of poliovirion type 2 RNA was determined to be VPg-pUUAAAACAG... which is identical to the sequence at the 5'-terminus of the poliovirus type 1 genome.