PSEUDORABIES VIRUS EPO IS FUNCTIONALLY HOMOLOGOUS TO VARICELLA-ZOSTERVIRUS ORF61 PROTEIN AND HERPES-SIMPLEX VIRUS TYPE-1 ICPO

Pseudorabies virus (PRV) early protein 0 (EP0) is the homolog of varic ella-zoster virus (VZV) open reading frame 61 (ORF61) protein and herp es simplex virus type 1 (HSV-1) ICP0. A PRV EP0 deletion mutant grows poorly in cell culture, suggesting that EP0 plays a critical role in t he viral replicative cycle, In this study, we have shown that the grow th defect of an EP0 deletion mutant was complemented in Vero cells exp ressing VZV ORF61 protein or HSV-1 ICP0. In transient expression assay s PRV EP0, like VZV ORF61 protein and HSV-1 ICP0, transactivates a var iety of promoters from PRV, VZV, HSV, and unrelated viruses. These dat a indicate that PRV EP0 is functionally homologous to VZV ORF61 protei n and HSV-1 ICP0. (C) 1995 Academic Press, Inc.