Ca2+-mediated degradation of central nervous system (CNS) proteins: topographic and species variation.
Ca2+-mediated degradation of central nervous system (CNS) proteins: topographic and species variation.
复制标题
Ca2 介导的中枢神经系统 (CNS) 蛋白降解：地形和物种变异。
DOI：
10.1007/bf00999722
复制
发表时间：
1987
影响因子：
3.6
通讯作者：
Hogan,EL
中科院分区：
文献类型：
--
作者：
Banik,NL;Happel,RD;Sostek,MB;Chiu,FC;Hogan,EL
大鼠、兔和牛脊髓的匀浆以及牛脑白质和灰质在钙(5 MM)存在下孵育后，神经丝三联体蛋白(NFP；200K、150K和69K)发生了广泛的降解。免疫印迹法鉴定NFP的降解产物。胶质纤维酸性蛋白(GFAP)、微管蛋白(MTP)和髓鞘蛋白也被降解。150K的NFP比其他NFP更敏感。钙介导的降解程度，大鼠脊髓略大于其他各组。牛脑白质的活性高于灰质，灰质没有明显的降解活性。EGTA和亮肽素都能阻止分解，但类似浓度的氯化镁(5 MM)则不起作用。这些结果表明，在几个物种的中枢神经系统(CNS)中，NFP被一种钙激活的中性蛋白酶降解。灰质中较低的活性表明该酶在轴突、髓鞘和/或少突胶质细胞中丰富。
Incubation of homogenates of rat, rabbit, and bovine spinal cord and of bovine brain white and gray matter in the presence of calcium (5 mM) produced an extensive degradation of the neurofilament triplet proteins (NFP; 200 K, 150K, and 69K). The breakdown products of the NFPs were identified by immunoblot. The glial fibrillary acidic protein (GFAP), microtubular proteins (MTP), and myelin proteins were also degraded. The 150 K NFP was more susceptible than the other NFPs. The extent of calcium-mediated degradation was slightly greater with rat spinal cord than the others. Bovine brain white matter had more activity than gray, which had no appreciable degradative activity. The breakdown was prevented by both EGTA and leupeptin but a similar concentration of MgCl2(5 mM) had no effect. These results suggest that NFPs are degraded by a Ca2+-activated neutral proteinase in the central nervous system (CNS) of several species. The lesser activity in gray matter suggests that the enzyme is enriched in axons, myelin, and/or oligodendroglial cells.