Myocardin drives formation of caveolae.

<p>Coronary smooth muscle cells, cultured on polycarbonate membranes, were transduced with Ad-CMV-MYOCD or Ad-CMV-null for 96h and prepared for electron microscopy. Left micrographs in panel A show control cells (Ad-CMV-null) where caveolae were rare. Rough endoplasmic reticulum was very prominent in these cultured cells. Right micrographs show caveolae in cells transduced with MYOCD (black arrowheads). Panel B shows quantification of the number of caveolae per μm membrane in cells from three independent transductions. The total membrane lengths examined for Ad-CMV-null and Ad-CMV-MYOCD were 501 and 340 μm, respectively. Panel C shows the diameters of caveolae in control and MYOCD transduced cells. Panel D shows area of rough endoplasmic reticulum compared to total cell area. Scale bars in the upper micrographs of panel A represent 500 nm whereas those in the lower micrographs represent 200 nm.