Johnson G V, Greenwood J A, Costello A C, Troncoso J C
Department of Psychiatry and Behavioral Neurobiology, University of Alabama, Birmingham 35294.
Neurochem Res. 1991 Aug;16(8):869-73. doi: 10.1007/BF00965535.
The in vitro degradation of individual neurofilament proteins by calpain and the effects of calmodulin on this proteolysis were studied. Two major results are reported. First, in the presence of calcium, calmodulin binds to the 200-kD neurofilament protein, but only weakly associates with the 150-kD neurofilament protein. The 70-kD neurofilament protein shows no specific calmodulin-binding. Second, calmodulin inhibits the calpain-mediated degradation of the 200-kD neurofilament protein, but does not alter the hydrolysis of the 150-kD and 70-kD neurofilament proteins. In addition, calmodulin is able to bind to the 200-kD neurofilament protein in the presence of other neurofilament subunits, indicating that calmodulin may play a role in the regulation of the metabolism of the 200-kD neurofilament protein in vivo.
研究了钙蛋白酶对单个神经丝蛋白的体外降解作用以及钙调蛋白对这种蛋白水解作用的影响。报道了两个主要结果。第一，在有钙存在的情况下，钙调蛋白与200-kD神经丝蛋白结合，但仅与150-kD神经丝蛋白弱缔合。70-kD神经丝蛋白未显示出特异性的钙调蛋白结合。第二，钙调蛋白抑制钙蛋白酶介导的200-kD神经丝蛋白的降解，但不改变150-kD和70-kD神经丝蛋白的水解。此外，在存在其他神经丝亚基的情况下，钙调蛋白能够与200-kD神经丝蛋白结合，这表明钙调蛋白可能在体内200-kD神经丝蛋白代谢的调节中发挥作用。
