Matsumoto A, Matsumoto R, Enomoto T, Baba H
Department of Radiation Biophysics and Genetics, Kobe University School of Medicine, Japan.
Neurosci Lett. 1996 Jun 21;211(2):105-8. doi: 10.1016/0304-3940(96)12723-3.
A polyclonal antibody against the 68 kDa beta-secretase was established, which recognizes a single 68 kDa band in brain homogenate of Alzheimer's disease patients and normal aged. Western analysis revealed that the protease is an acidic glycoprotein with negative charge on its glycoconjugate(s). Sensitiveness to heparitinase and glycopeptidase A indicates that the protease contains asparagine-linked oligosaccharide with heparan sulfate moieties. Specific detection of the 68 kDa band in the analysis using anti-heparan sulfate antibody, and its time-course-dependent degradation, also confirm the above results. It seems that, like human blood coagulation factors IXa and XIa, the glycoconjugate(s) attached to the protease interfere with substrate specificity, stability and topological restriction of proteolysis in brain extracellular matrix, where diffuse plaque formation is taking place.
制备了一种针对68 kDaβ-分泌酶的多克隆抗体，该抗体在阿尔茨海默病患者和正常老年人的脑匀浆中识别出一条单一的68 kDa条带。蛋白质印迹分析显示，该蛋白酶是一种酸性糖蛋白，其糖缀合物带有负电荷。对肝素酶和糖肽酶A的敏感性表明，该蛋白酶含有带有硫酸乙酰肝素部分的天冬酰胺连接寡糖。在使用抗硫酸乙酰肝素抗体的分析中对68 kDa条带的特异性检测及其时间进程依赖性降解也证实了上述结果。似乎与人类凝血因子IXa和XIa一样，附着在该蛋白酶上的糖缀合物会干扰脑细胞外基质中蛋白水解的底物特异性、稳定性和拓扑限制，而脑内细胞外基质正是发生弥漫性斑块形成的地方。
