Differential effect of the IE1 trans activator on the transcription levels from various promoters. Each promoter-Luc construct was co-transfected with phsp82Renilla Luc, both in the absence and presence of the IE1 trans activator, and assayed for both firefly and Renilla luciferase expression, 24 hrs. post-transfection. One experiment with six replicates was performed with the same batch of cells, DNA/liposome complexes and luciferase reagents. Error is reported as +/- 1 standard error. Each set of data is plotted both on a linear and a log scale. (A) Addition of the trans activator (+) caused a 16-fold increase in firefly luciferase expression from the Act5C promoter, a 169-fold increase in expression from the IE1 promoter and an 11-fold increase in expression from the pUb promoter. (B) The same data as shown in (A) but plotted on a log scale. (C) Addition of the trans activator resulted in different levels of expression from the phsp82Renilla Luc construct depending upon which promoter was used to drive expression of the firefly luciferase construct. (D) The same data as shown in (C) but plotted on a log scale.