FIGURE 2.
Impact of a PLE on mRNA and protein expression in vivo. Cells were transfected with firefly luciferase (Fluc) constructs without (control) and with (+PLE) a PLE together with a plasmid expressing Renilla luciferase (Rluc). (A) RNA extracted 24 h after transfection was analyzed by Northern blot using [32P]-labeled probes to each mRNA. Radioactivity was visualized by PhosphorImager analysis. (B) Luciferase activity was measured in cytoplasmic extracts 24 h after transfection. The data are presented as the ratio of firefly (Fluc) to Renilla (Rluc) activity and show the mean ± standard deviation for triplicate determinations. Shown are typical results from three independent experiments.