Various Jobs of Proteolytic Enzymes in Skeletal Muscle during Unloading: Facts and Speculations
Figure 1
Interaction between proteolytic systems in mammals skeletal muscles under disuse atrophy. Preliminary disorganization of myofibrils by calpains helps to degrade myofibril proteins by UPS. Ca2+ accumulation can activate calpains localized near Z-disk. Main calpains target is titin, whose cleavage leads to E3-ubiquitin ligases activation.