Malik M N, Sheikh A M, Fenko M D, Wisniewski H M
Life Sci. 1986 Oct 13;39(15):1335-43. doi: 10.1016/0024-3205(86)90331-0.
The effect of the three forms (CANP1, CANP2 & CANP3) of calf brain calcium activated neutral protease (CANP) on the hydrolysis of purified neurofilament triplet proteins was investigated. It was observed that: each of the purified neurofilament proteins, was hydrolyzed slowly by CANP2 whereas the hydrolysis of 150 KDa and 68 kDa proteins by CANP1 & CANP3 was rapid; when assembled neurofilaments were used as a substrate, again differences in the rate and extent of degradation of the triplet proteins by the three proteases were observed. For example, little cleavage of the 68 kDa protein by CANP2 and CANP3 was noted whereas 210 kDa and 150 kDa proteins remained largely intact. CANP1 degraded the 150 kDa and 68 kDa proteins more rapidly than 210 kDa protein, where only a slight effect was noted. These data provide further proof of the existence of three different forms of CANP in the brain, and indications of the resistance of 210 kDa protein to proteolysis which may be compatible with its proposed special role in crossbridge formation.
研究了小牛脑钙激活中性蛋白酶（CANP）的三种形式（CANP1、CANP2和CANP3）对纯化的神经丝三联体蛋白水解的影响。观察到：每种纯化的神经丝蛋白，被CANP2缓慢水解，而CANP1和CANP3对150 kDa和68 kDa蛋白的水解迅速；当使用组装好的神经丝作为底物时，再次观察到三种蛋白酶对三联体蛋白降解的速率和程度存在差异。例如，CANP2和CANP3对68 kDa蛋白的切割很少，而210 kDa和150 kDa蛋白基本保持完整。CANP1降解150 kDa和68 kDa蛋白的速度比210 kDa蛋白快，对210 kDa蛋白只有轻微影响。这些数据进一步证明了大脑中存在三种不同形式的CANP，并表明210 kDa蛋白对蛋白水解具有抗性，这可能与其在桥连形成中所提出的特殊作用相一致。
