FIG. 7.

Effect of the coexpression of EBV Rta on the activation of early antigen by mutants with point mutations in the basic domain of ZEBRA. BZKO cells were transfected with vectors expressing the wild-type (gZ) or mutant ZEBRA proteins. In one set of cells, the empty vector, pRts, was cotransfected; in the other set of cells, the pRts vector expressing Rta (pRta) was cotransfected. Immunoblots of cell extracts prepared 48 h after transfection were probed for Rta, EA-D, and ZEBRA (Z) with monospecific antibodies. X, a cross-reactive protein detected by the antibody to Rta that controls for protein loading; E, early mutant; R, Rta.