FIG. 6.

Intracellular colocalization of p53 and Ad12 E1B-55 kDa. H1299 cells were transiently transfected with plasmids (400 ng) expressing HA-tagged Ad12 E1B-55 kDa. In addition, expression plasmids (100 ng) for wild-type or mutant (mt) (L22Q/W23S) p53 were cotransfected as indicated. As a control, the corresponding empty vector was transfected instead of the E1B expression plasmid (a and b). The cells were fixed and stained simultaneously with murine anti-HA antibody and rabbit anti-p53 antibody, followed by secondary antibodies labeled with different fluorescent dyes. Cells with strong expression of Ad12 E1B-55 kDa were monitored. The same areas were visualized for expression of E1B-55 kDa (a, c, and e) and p53 (b, d, and f). Note that in panel e, a cell that expressed Ad12 E1B-55 kDa almost exclusively in the cytoplasm was chosen. This pattern was not always observed (compare Fig. 5) but is shown here to facilitate the observation of any colocalization with p53.