FIG. 4.

Transcriptional activation of promoter/CAT reporters by ZEBRA and a panel of Z(S186) mutants. (A) Activation of BMRF1p/CAT. BJAB cells were transfected with 10 μg of BMRF1 promoter reporter plasmid and 10 μg of wild-type (wt) or mutant BZLF1 expression plasmid. The wild type and mutants are indicated by the amino acid present at position 186. The data represent the mean and standard error of the mean of three separate transfections. Fold activation is percent acetylation in the presence of BZLF1 or mutant expression vector/percent acetylation in the presence of CMV vector alone. (B) Activation of BRLF1p/CAT (Rp/CAT). BJAB cells were cotransfected with 10 μg of Rp/CAT reporter and with a total of 10 μg of activator plasmid. The activator consisted of 5 μg of BZLF1 or mutant expression vector plus 5 μg of vector alone (CMV) (solid bars) or 5 μg of Rta (open bars). Transfection efficiency was corrected by transfection of 1 μg of pGL2 Basic + HMP. Fold activation is relative to the level with reporter together with 10 μg of CMV. Synergy index: percent acetylation by ZEBRA or Z(S186) mutant in the presence of Rta/percent acetylation by ZEBRA or mutant alone plus percent acetylation by Rta alone.