Isolation and characterization of extremely minor gangliosides, GM1b and GD1 alpha, in adult bovine brains as developmentally regulated antigens.
Isolation and characterization of extremely minor gangliosides, GM1b and GD1 alpha, in adult bovine brains as developmentally regulated antigens.
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成年牛大脑中作为发育调节抗原的极小神经节苷脂 GM1b 和 GD1 α 的分离和表征。
DOI：
10.1016/s0021-9258(19)39049-0
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发表时间：
1990
期刊：
影响因子：
--
通讯作者：
S. Ando
中科院分区：
文献类型：
--
作者：
Y. Hirabayashi;A. Hyogo;T. Nakao;K. Tsuchiya;Y. Suzuki;M. Matsumoto;K. Kon;S. Ando
除神经节苷脂GM1b外，通过Q-Sepharose和Iatrobeads柱层析，还从牛脑中有效分离到了一种罕见且极少量的神经节苷脂GD1 α。在纯化过程中，通过高灵敏度的TLC/酶免疫染色法证实了唾液酸酶不稳定的神经节苷脂的存在。通过气液色谱、过甲基化研究、唾液酸酶降解、特异性抗体免疫染色、快速原子轰击-质谱分析和质子磁共振谱分析对其结构进行了表征。神经节苷脂在总神经节苷脂中含量极低（0.016%）。这一发现提示，在哺乳动物大脑中可能存在asialo GM1----GM1b----GD1 α的合成途径。用纯化的GM1b免疫小鼠获得的单克隆抗体NA-6与GM1b特异性反应，但与其他结构相关的神经节苷类如GM1a、GD1a等无交叉反应性。采用TLC/ NA-6免疫染色的方法，发现GM1b在胚胎14-17天在鸡脑中强烈表达。因此，假设在成人大脑中发现的极少量神经节苷类如GM1b和GD1 α具有胚胎分子的特征。
In addition to ganglioside GM1b, an unusual and extremely minor ganglioside, GD1 alpha, was efficiently isolated from bovine brain by combination of Q-Sepharose and Iatrobeads column chromatographies. In the course of purification steps, the presence of the sialidase-labile ganglioside was proved by a highly sensitive TLC/enzyme-immunostaining method. The structure was characterized by gas-liquid chromatography, permethylation study, sialidase degradation, immunostaining with specific antibodies, fast atom bombardment-mass spectrometry, and proton magnetic resonance spectrometry. The content of the ganglioside was very small (0.016%) in the total gangliosides. This finding suggests that a synthetic pathway of asialo GM1----GM1b----GD1 alpha may exist in mammalian brains. A monoclonal antibody NA-6 that was obtained by immunizing mice with purified GM1b reacted specifically with GM1b but showed no cross-reactivity with other structurally related gangliosides such as GM1a, GD1a, and so on. Using the method of TLC/immunostaining with NA-6, GM1b was found to be strongly expressed during embryonic days 14-17 in chick brains. Thus, it is assumed that extremely minor gangliosides like GM1b and GD1 alpha found in adult brains are characterized as embryonic molecules.