Machamer C E, Florkiewicz R Z, Rose J K
Mol Cell Biol. 1985 Nov;5(11):3074-83. doi: 10.1128/mcb.5.11.3074-3083.1985.
We investigated the role of glycosylation in intracellular transport and cell surface expression of the vesicular stomatitis virus glycoprotein (G) in cells expressing G protein from cloned cDNA. The individual contributions of the two asparagine-linked glycans of G protein to cell surface expression were assessed by site-directed mutagenesis of the coding sequence to eliminate one or the other or both of the glycosylation sites. One oligosaccharide at either position was sufficient for cell surface expression of G protein in transfected cells, and the rates of oligosaccharide processing were similar to the rate observed for wild-type protein. However, the nonglycosylated G protein synthesized when both glycosylation sites were eliminated did not reach the cell surface. This protein did appear to reach a Golgi-like region, as determined by indirect immunofluorescence microscopy, however, and was modified with palmitic acid. It was also apparently not subject to increased proteolytic breakdown.
我们研究了糖基化在水泡性口炎病毒糖蛋白（G）的细胞内运输及细胞表面表达中的作用，该研究在通过克隆cDNA表达G蛋白的细胞中进行。通过对编码序列进行定点诱变以消除一个或另一个或两个糖基化位点，评估了G蛋白的两个天冬酰胺连接聚糖对细胞表面表达的个体贡献。在转染细胞中，任一位置的一个寡糖对于G蛋白的细胞表面表达就足够了，并且寡糖加工速率与野生型蛋白观察到的速率相似。然而，当两个糖基化位点都被消除时合成的非糖基化G蛋白未到达细胞表面。通过间接免疫荧光显微镜检查确定，该蛋白似乎确实到达了类似高尔基体的区域，并且用棕榈酸进行了修饰。它显然也没有受到蛋白水解降解增加的影响。
