Effect of HPyV9 LTAg on the early and late promoters of HPyV9 and UF1. BEL7402 (panel A), HEK293 (panel B), and HeLa cells (panel C) were co-transfected with the luciferase reporter plasmid containing the H9-E, H9-L, UF1-E, or UF1-L promoter, and empty vector pcDNA3.1(+) or expression plasmid for HPyV9 LTAg. Luciferase values were measured and corrected for the protein concentration. Each experiment was repeated three to five times (Appendix A). A representative experiment for each promoter and each cell line is shown. Each bar represents the average of three independent parallels ± standard deviation. (Panel D) Fold induction of the promoter by HPyV9 LTAg. The average (range) of three to four independent experiments is given.