Fig. 1.

PKG enhanced myocardin (Myocd)-induced SM22 promoter activity. A: COS-7 cells were transiently transfected with Myocd (6, 12.5, or 25 ng)- with or without PKG-Iα (10, 50, or 100 ng)-expressing plasmids and SM22 promoter-driven firefly luciferase reporter plasmid. Inset: lysates for essays were immunoblotted to confirm that cotransfection of PKG and Myocd does not affect the expression of Myocd protein. B: Myocd-expressing plasmids (0.2 μg) were transiently cotransfected with SM22 promoter-driven reporter plasmid in control rat aortic smooth muscle cells [SMCs; control (Cont)] or stably PKG-expressing rat aortic SMCs (PKG-Iα). EV, empty vector. A similar expression of myocardin protein in the control and PKG-Iα cell lines was shown by immunoblot. SM22 promoter-driven firefly luciferase activities were normalized with the cotransfected renilla luciferase activity (A) or β-galactosidase activity (B). Relative luciferase activity is expressed as fold activation above the level of expression of the reporter gene alone. *P < 0.01 indicated myocardin-induced promoter activity in PKG-expressing cells vs. the control group. Data are representative of at least 3 independent experiments performed in triplicate.