GLYCOPROTEIN-110, THE EPSTEIN-BARR-VIRUS HOMOLOG OF HERPES-SIMPLEX VIRUS GLYCOPROTEIN-B, IS ESSENTIAL FOR EPSTEIN-BARR-VIRUS REPLICATION IN-VIVO

The Epstein-Barr virus (EBV) glycoprotein gp110 has substantial amino acid homology to gB of herpes simplex virus but localizes differently within infected cells and is essentially undetectable in virions. To i nvestigate whether gp110, like gB, is essential for EBV infection, a s electable marker was inserted within the gp110 reading frame, BALF4, a nd the resulting null mutant EBV strain, B95-110HYG, was recovered in lymphoblastoid cell lines (LCLs). While LCLs infected with the parenta l virus B95-8 expressed the gp110 protein product following productive cycle induction, neither full-length gp110 nor the predicted gp110 tr uncation product was detectable in B95-110HYG LCLs. Infectious virus c ould not be recovered from B95-110HYG LCLs unless gp110 was provided i n trans. Rescued B95-110HYG virus latently infected and growth transfo rmed primary B lymphocytes. Thus, gp110 is required for the production of transforming virus but not for the maintenance of transformation o f primary B lymphocytes by EBV.