Casein kinase II specifically nucleotidylylates in vitro the amino acid sequence of the protein encoded by the alpha 22 gene of herpes simplex virus 1.

An earlier report has shown that eight viral proteins with a common amino acid sequence (R/P)RA(P/S)R are nucleotidylyated in vitro by nuclear extracts from cells infected with herpes simplex virus 1. One, the product of the alpha 22 gene, is nucleotidylylated in the absence of viral proteins made late in infection. A chimeric protein (GST22P) consisting of amino acids 50-200 of the alpha 22 coding sequence fused to the C terminus of the glutathione S-transferase was nucleotidylylated by enzymes in nuclear extracts of infected or mock-infected cells and also by a casein kinase II enzyme purified from the sea star. The enzyme did not nucleotidylylate common casein kinase II substrates (casein, phosvitin) and the reaction was inhibited by heparin. The results are consistent with the hypothesis that nucleotidylylation of the eight viral proteins involves casein kinase II. IMAGES: