The herpes simplex virus 1 Us3 kinase is involved in assembly of membranes needed for viral envelopment and in distribution of glycoprotein K

Us3 is a non-essentail viral kinase involved in regulation of apoptosis, membrane biosynthesis postulated to act via phopshorylation of many viral and cellular substrate. gK is an essential hydrophobic viral glycoprotein postulated to act excludisvely at the Golgi level. Immunolabelling using a hemagglutinin (HA) tagged Us3 deletion mutant revealed localisation of gK in nuclei, cytoplasm, on nuclear and Golgi membranes and on envelopes of viruses in the perinuclear space that derive by buding of capsids at nuclear membranes. We conclude that Us3 has an impact on gK synthesis and/or distribution in association with regulation of membrane biosynthesis. The presence of gK at nuclear membranes and viral envelopes strongly indicates that gK plays a signifcant role in nucleus-to-cytoplasm capsid translocation