ASSOCIATION OF HERPES-SIMPLEX VIRUS REGULATORY PROTEIN ICP22 WITH TRANSCRIPTIONAL COMPLEXES CONTAINING EAP, ICP4, RNA-POLYMERASE-II, AND VIRAL-DNA REQUIRES POSTTRANSLATIONAL MODIFICATION BY THE U(L)13 PROTEIN-KINASE

The expression of herpes simplex virus 1 gamma (late) genes requires f unctional alpha proteins (gamma(1) genes) and the onset of viral DNA s ynthesis (gamma(2) genes), We report that late in infection after the onset of viral DNA synthesis, cell nuclei exhibit defined structures w hich contain two viral regulatory proteins (infected cell proteins 4 a nd 22) required for gamma gene expression, RNA polymerase II, a host n ucleolar protein (EAP or L22) known to be associated with ribosomes an d to bind small RNAs, including the Epstein-Barr virus small nuclear R NAs, and newly synthesized progeny DNA. The formation of these complex es required the onset of viral DNA synthesis. The association of infec ted cell protein 22, a highly posttranslationally processed protein, w ith these structures did not occur in cells infected with a viral muta nt deleted in the genes U(L)13 and U(S)3, each of which specifies a pr otein kinase known to phosphorylate the protein.