Machamer C E, Rose J K
Molecular Biology and Virology Laboratory, Salk Institute, San Diego, California 92138.
J Biol Chem. 1988 Apr 25;263(12):5955-60.
In this report we have extended our studies on a panel of vesicular stomatitis virus G proteins with altered glycosylation sites. These mutant proteins were generated by oligonucleotide-directed mutagenesis of the coding sequence to create new consensus sites for asparagine-linked oligosaccharide addition. We report that the intracellular transport of most of the mutant proteins is temperature-sensitive, implying a polypeptide folding step is affected. In addition, we find that the nonglycosylated G protein and those mutant proteins which lack oligosaccharides at the normal positions are subject to aberrant intermolecular disulfide bonding, leading to the accumulation of large complexes in the endoplasmic reticulum. These results imply that carbohydrate plays an indirect role in the intracellular transport of G protein.
在本报告中,我们扩展了对一组糖基化位点改变的水疱性口炎病毒G蛋白的研究。这些突变蛋白是通过对编码序列进行寡核苷酸定向诱变产生的,以创建新的天冬酰胺连接寡糖添加共有位点。我们报告称,大多数突变蛋白的细胞内运输对温度敏感,这意味着多肽折叠步骤受到影响。此外,我们发现非糖基化的G蛋白以及那些在正常位置缺乏寡糖的突变蛋白会发生异常的分子间二硫键结合,导致内质网中积累大的复合物。这些结果表明,碳水化合物在G蛋白的细胞内运输中起间接作用。