Hou Lin, Kousaku Ohno
Medical College, Qingdao University, Qingdao Shandong 266021 P. R. China.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi. 2003 Apr;20(2):103-6.
To study the molecular mechanism of GM(2) gangliosidosis.
The skin fibroblasts from 4 patients with GM(2) gangliosidosis were subjected to culture. Enzyme activities assay, Western blot and immunocytochemical analysis were performed using the cultured fibroblasts.
The hexosaminidase (Hex) activities of 4 patients with GM(2) gangliosidosis were significantly decreased. The activities were 12% 3% 15% and 6% of control values, respectively. Western blot analysis indicated that the amount of Hex mature alpha- and beta- subunits (alpha m, beta m) was decreased in cells from patients 2 and 3, but only decreased alpha m was found in patient 1 and both alpha m and beta m were normal in cells from patient 4. Immunocytochemical analysis revealed the accumulated GM(2) ganglioside in cells from patients 1-4.
The pathogenesis of GM(2) gangliosidosis was associated with deficiency of Hex alpha m and beta m and GM(2) activator caused by HEXA, HEXB and GM(2)A gene mutations.
研究GM(2)神经节苷脂沉积症的分子机制。
对4例GM(2)神经节苷脂沉积症患者的皮肤成纤维细胞进行培养。对培养的成纤维细胞进行酶活性测定、蛋白质印迹法和免疫细胞化学分析。
4例GM(2)神经节苷脂沉积症患者的己糖胺酶(Hex)活性显著降低。活性分别为对照值的12%、3%、15%和6%。蛋白质印迹分析表明,患者2和3的细胞中Hex成熟的α和β亚基(αm,βm)量减少,但患者1中仅发现αm减少,患者4的细胞中αm和βm均正常。免疫细胞化学分析显示患者1 - 4的细胞中GM(2)神经节苷脂蓄积。
GM(2)神经节苷脂沉积症的发病机制与由HEXA、HEXB和GM(2)A基因突变导致的Hexαm和βm以及GM(2)激活剂缺乏有关。