Hashim O H, Cushley W
Department of Biochemistry, University of Glasgow, Scotland, U.K.
Mol Immunol. 1987 Oct;24(10):1087-96. doi: 10.1016/0161-5890(87)90077-0.
The effects of inhibition of N-linked oligosaccharide processing by glucosidase and mannosidase activities upon secretion of rat hybridoma IgM and IgG have been investigated. The inhibitor of glucosidase I, castanospermine, prevents conversion of the N-linked carbohydrate groups of IgM to a complex form as assessed by resistance to digestion by endo H. The rate of secretion of IgM or IgG from the treated cells is not diminished relative to controls. Similar data are obtained for studies employing the inhibitor of glucosidase I and II activities, 1-deoxynojirimycin. Inhibition of processing by the mannosidase inhibitors 1-deoxymannojirimycin and swainsonine leads to alteration of the qualitative structure of the oligosaccharide groups present on IgG molecules, but again has no effect upon the rate of export of IgG or IgM molecules from treated cells. In each case studied the mu or gamma heavy chains isolated from lysates or culture supernatants of cells treated with glucosidase inhibitors had a higher Mr than the equivalent chains isolated either from control cultures or cultures exposed to either mannosidase inhibitor.
已研究了通过葡糖苷酶和甘露糖苷酶活性抑制N-连接寡糖加工对大鼠杂交瘤IgM和IgG分泌的影响。葡糖苷酶I抑制剂栗精胺可阻止IgM的N-连接碳水化合物基团转化为复合形式，这可通过对内切糖苷酶H消化的抗性来评估。与对照相比，处理过的细胞中IgM或IgG的分泌速率并未降低。使用葡糖苷酶I和II活性抑制剂1-脱氧野尻霉素进行的研究也获得了类似的数据。甘露糖苷酶抑制剂1-脱氧甘露野尻霉素和苦马豆素对加工的抑制导致IgG分子上存在的寡糖基团的定性结构发生改变，但同样对处理过的细胞中IgG或IgM分子的输出速率没有影响。在所研究的每种情况下，从用葡糖苷酶抑制剂处理的细胞的裂解物或培养上清液中分离的μ或γ重链的相对分子质量高于从对照培养物或暴露于任何一种甘露糖苷酶抑制剂的培养物中分离的等效链。
