Garnier G, Davrinche C, Charlionet R, Fontaine M
Institut National de la Santé et de la Recherche Médicale, Unité 78, Bois-Guillaume, France.
Complement. 1988;5(2):77-88. doi: 10.1159/000463038.
The involvement of sialic acids in the microheterogeneity of human complement factor B was investigated. Desialylation kinetics revealed all the charge intermediates from a complex native to a homogeneous form. The relation between this heterogeneity and posttranslational events was explored in cultured hepatoma cells. Intracellular factor B exhibited the same isoelectric focusing pattern as the desialylated purified protein, whereas a highly heterogeneous form was secreted. In contrast, when N-glycosylation was prevented by tunicamycin, both intracellular and secreted forms focused like intracellular factor B from control cultures. These data lead to the conclusion that the microheterogeneity of human factor B results from different degrees of sialylation of its N-glycans.
研究了唾液酸在人补体因子B微观异质性中的作用。去唾液酸化动力学揭示了从复杂天然形式到均一形式的所有电荷中间体。在培养的肝癌细胞中探索了这种异质性与翻译后事件之间的关系。细胞内因子B呈现出与去唾液酸化纯化蛋白相同的等电聚焦模式，而分泌形式则高度异质。相比之下，当用衣霉素阻止N-糖基化时，细胞内和分泌形式的聚焦情况都类似于对照培养物中的细胞内因子B。这些数据得出结论，人因子B的微观异质性源于其N-聚糖不同程度的唾液酸化。
