FIG 6.

BPLF1 expression increases Rad18 protein levels. (A) 293EBV+ cells were transfected with BPLF1 1-246, and the lytic cycle was induced with BZLF1. Immunoblotting revealed a substantial increase in Rad18 protein levels when BPLF1 was expressed. Rad6 levels remained largely unchanged. EA-D is an EBV early protein that indicates induction of the lytic program. (B) 293T cells were transfected with functional (BPLF1 1-246) or nonfunctional (BPLF1 C61S) BPLF1. Rad18 levels were increased only in the presence of functional BPLF1. (C) Induction of BPLF1 knockout virus results in less Rad18 protein levels than with the WT. WT and BPLF1 knockout viruses were induced into the lytic replication cycle by transfection of BZLF1. Levels of Rad18 were normalized to GAPDH protein levels.