Figure 1.

Caspase-3 degrades actomyosin. (a) Recombinant caspase-3 was added to purified actomyosin in vitro, and the mixture was incubated at 37°C for 2 hours. Western blot analysis of the reaction products was performed with polyclonal antibodies against the carboxy terminus of α-actin. The results revealed a characteristic 14-kDa actin fragment. (b) Purified recombinant caspase-3 was added to lysates of L6 skeletal muscle cells or to lysates of rat psoas muscle, and the mixture was incubated at 37°C for 2 hours. Immunoblot analysis of the reaction products demonstrated the appearance of the 14-kDa actin fragment.