Ad-eIF5A1 infection induces increased expression and phosphorylation of p53 tumor suppressor protein. A549 lung carcinoma cells were infected with adenovirus expressing either LacZ (L) or eIF5A1 (5A). Four hours after infection, the media was replaced with media containing either DMSO, 10 μM of p38 inhibitor SB203580 (SB), 10 μM of the JNK inhibitor SP600125 (JNK), or 10 μM of the MEK inhibitor U1026. Forty-eight hours later the cell lysate was harvested. Western blots were performed on the lysate using antibodies directed against either total p53 (p53), or p53 phosphorylated on ser15, ser37, or ser392. The data is representative of three independent experiments.