Electrophoretic separation of ventricular myosin isoenzymes using a native polyacrylamide minigel system

A method is presented to separate rabbit cardiac ventricular myosin isoenzymes (V(1), V(2), V(3)), which are large and important contractile proteins. This polyacrylamide gel electrophoresis--using a slab minigel format--does not involve preparation of an acrylamide gradient or denaturing conditions. The isoenzyme migration order was confirmed through identification with an anti beta-myosin heavy chain in cardiac ventricles (i.e., V(3)) antibody. Extracts from atrial and soleus muscle were used as positive control for V(1) and V(3), respectively. The relative quantification was obtained densitometrically and analyzed via TINA/Software. The reproducibility of method was additionally tested. The procedure employs Coomassie blue staining and is rapid and reproducible. Thus, the method permits easy and economic analysis of myosin isoenzymes under native conditions.