FIG. 4.

Z and R increase phosphorylation of ATF2. HeLa cells were infected with adenovirus (Ad)-LacZ, adenovirus-Z, or adenovirus-R as indicated. Immunoblot analysis was performed with antibodies directed against total ATF2 and phosphorylated ATF2 (A) or total CREB and phosphorylated CREB/ATF1 (B). Both phosphorylated CREB and phosphorylated ATF1 are recognized by a single antibody. At least two separate experiments are presented for each antibody. Infection of cells with adenovirus-LacZ did not affect ATF2, ATF1, or CREB phosphorylation in comparison to levels in mock-infected cells (data not shown).