FIG. 10.

HDAC activity contributes to the PKA inhibitory effect on MEF2D. (A) Cos7 cells were transfected with empty vector or pcDNA3-MEF2D (wild type or mutant [S121/190A]), with and without pFC-PKA. pGL3-4 × MEF2-Luc was used as the reporter gene. pCMV-β-galactosidase was transfected as an internal control for transfection efficiency. Cells were treated with or without 0.1 μM TSA for 16 h prior to being harvested. (B) EMSA was used to determine whether PKA modulates MEF2D DNA binding properties. (Top) PKA does not alter the DNA binding properties of wild-type MEF2D or S121/190A mutant MEF2D. The inclusion of HDAC4 with PKA does appear to stabilize the MEF2D DNA binding complex. (Bottom) Western blots of the extracts used in EMSA.