Nathan B, Bao J, Hsu C C, Yarom M, Deupree D L, Lee Y H, Tang X W, Kuo C Y, Burghen G A, Wu J Y
Department of Physiology and Cell Biology, University of Kansas, Lawrence 66045.
Brain Res. 1994 Apr 11;642(1-2):297-302. doi: 10.1016/0006-8993(94)90934-2.
A new and novel form of L-glutamate decarboxylase (GAD; EC 4.1.1.15) was purified from whole porcine brain to apparent homogeneity by a combination of column chromatographies on DE-52, ultragel AcA 34, hydroxylapatite and Sephadex G-200, and native gel electrophoresis. The purified GAD was established as an integral membrane protein based on hydrophobic interaction chromatography and membrane extraction studies. This membrane GAD (MGAD) has a native molecular weight of 120 +/- 5 kDa and is a homodimer of 60 +/- 2 kDa. Immunoprecipitation and immunoblotting tests using the sera from insulin-dependent diabetes mellitus (IDDM) patients revealed the presence of antibodies against this newly identified MGAD in IDDM. The role of MGAD in the pathogenesis of IDDM and related autoimmune disorders is also discussed.
通过在DE - 52、超凝胶AcA 34、羟基磷灰石和葡聚糖凝胶G - 200上进行柱色谱以及天然凝胶电泳相结合的方法，从整个猪脑中纯化出一种新型的L - 谷氨酸脱羧酶（GAD；EC 4.1.1.15），达到了表观均一性。基于疏水相互作用色谱和膜提取研究，纯化的GAD被确定为一种整合膜蛋白。这种膜GAD（MGAD）的天然分子量为120±5 kDa，是由60±2 kDa的同型二聚体组成。使用胰岛素依赖型糖尿病（IDDM）患者的血清进行免疫沉淀和免疫印迹试验，结果显示IDDM患者体内存在针对这种新鉴定出的MGAD的抗体。本文还讨论了MGAD在IDDM发病机制及相关自身免疫性疾病中的作用。
