Plays several roles during the time course of infection, including egress of virus particles from the perinuclear space and secondary envelopment of cytoplasmic capsids that bud into specific trans-Golgi network (TGN)-derived membranes. Oligomerizes. Interacts with BBRF2; this interaction mediates BBRF2 incorporation to virions. Phosphorylated. Palmitoylation is necessary for Golgi localization. Belongs to the herpesviridae UL51 family.