FIG. 6.
Basal expression levels from the pOri16L plasmids. SCC-13 cells were transfected with 0.05 μg of pRL-TK and 0.5 μg of pCMV4-XS plus 1 μg of each pOri16L template. Dual luciferase assays were performed on cell extracts prepared at 36 h posttransfection. The luciferase activity for each cell lysate was expressed as the ratio between the firefly and Renilla luciferase activities and then normalized to the pOri16L wild-type (W.T.) levels (100%) for comparisons between experiments. The average results from three independent experiments are plotted for each set of templates. (A) E2BS#3; (B) E2BS#2; (C) E2BS#1; (D) constructs with alterations to more than one E2BS. Error bars correspond to the standard deviation for each data set.