Figure 4.

Mdm2 augments the activity of CREB. (a) P53^−/− and p53^−/−;mdm2^−/− MEFs were treated with IBMX for 4 h. mRNA levels were measured using real-time PCR. Areg, amphiregulin; CREM, cAMP-response element modulator; Dusp1, dual-specificity phosphatase 1; Hlf, hepatic leukemia factor. (b) P53^−/−;mdm2^−/− MEFs were transfected with UAS-GAL luciferase reporter plasmid, CMV-β-galactosidase reporter plasmid, GAL4-CREB and increasing levels of a vector expressing Mdm2. Cells were treated overnight with vehicle or forskolin. Luciferase activity was normalized to β-galactosidase measurements. (c) P53^−/− and p53^−/−;mdm2^−/− MEFs were treated with TPA for 1 h. mRNA levels were measured using real-time PCR