Sohar I, Bird J W, Moore P B
Biochem Biophys Res Commun. 1986 Feb 13;134(3):1269-75. doi: 10.1016/0006-291x(86)90387-6.
In several myopathic disorders, the internal muscle cell calcium concentration increases significantly as compared to normal muscle cells. We report that in the presence of elevated calcium levels, the calcium-binding proteins troponin C and calmodulin are protected from digestion by the chymotrypsin-like serine proteinase that co-purifies with isolated myofibrils. Degradation of the 67k calcimedin in the presence of calcium shows altered major cleavage fragments while degradation of myosin is unaffected by the presence of calcium. A role for this serine proteinase in muscle-wasting diseases is suggested.
