FIG. 1.

Wild-type p53, p73α, and p73β transactivate p53-responsive reporters in mammalian cells (A and B). H1299 cells (grown in DMEM supplemented with 10% FBS) were transiently cotransfected with the CMV-HA:p53, CMV-HA:p73α, or CMV-HA:p73β expression plasmid along with the luciferase (luc) reporter constructs indicated in boxes at the bottom. Cells were harvested for luciferase assay 18 h after cotransfection. Results are represented as fold induction of luciferase activity compared to control cells transfected with an empty CMV expression plasmid. Histograms show the mean of a typical experiment of three performed in triplicate; bars indicate the standard deviation of the mean. (C) Representative Western blot analysis. A blot loaded with 100 μg of extract was probed with the anti-HA antibody 16B12 to detect the expression levels of HA:p53, HA:p73α, and HA:p73β in transfected cells. Ct, control plasmid.