MAML1 regulates EGR1 mRNA and protein expression.

(A) HEK-293 cells were transfected with MAML1 siRNA or control (Ctrl) siRNA, and cultured in the presence of TPA to induce expression of EGR1. Proteins were detected by immunoblotting using antibodies recognizing MAML1, EGR1 and GAPDH. (B) Whole cell extracts were prepared from cells expressing MAML1 and control HEK-293 cells cultured with TPA. Proteins were detected by immunoblotting using the indicated antibodies. (C) HEK-293 cells were transfected with MAML1 siRNA or control siRNA, cultured with TPA; then EGR1 mRNA expression was analyzed by real-time PCR. (D) HEK-293 control cells and HEK-293 cells stably expressing FLAG-MAML1 were cultured with TPA; then EGR1 mRNA expression was analyzed by real time PCR. The data is presented as the mean ± standard error of the mean (SEM) and expressed relative to EGR1 levels in control HEK-293 cells cultured in the absence of TPA.