FIGURE 5.

STAT3 attenuates the SRF-dependent transcriptional activation of CArG box containing contractile VSMC-specific genes. A and B, T/G HA-VSMCs were transiently transfected with myocardin, myocardin/STAT3, or a control vector (pcDNA3.1) for 24 h, and ChIP assays were performed by PCR with primers targeting ACTA2 and SM22α as described under “Experimental Procedures.” Sheared DNA-protein complexes were immunoprecipitated by using an anti-Myc-myocardin antibody followed by PCR to detect the endogenous CArG regions. The amount of DNA in each sample (2% input) is shown in the 2nd lane. Immunoprecipitations without primary antibody (No Ab) serve as a mock-treated control and IgG as a negative control.