Kotwal G J, Buller M L, Wunner W H, Pringle C R, Ghosh H P
J Biol Chem. 1986 Jul 5;261(19):8936-43.
A temperature-sensitive mutant (ts gamma 1) of the Cocal serotype of vesicular stomatitis virus synthesizes at the permissive temperature (32 degrees C) a glycoprotein G whose size is smaller (Mr 68,000) than the wild-type (Mr 71,000) and that renders the virion thermolabile. At the nonpermissive temperature (39 degrees C), reduced amounts of noninfectious virus-like particles deficient in G protein were produced. The size of the intracellular G protein was further decreased (Mr 64,000) at the nonpermissive temperature. Biochemical studies including sugar labeling, tryptic peptide analysis, and NH2-terminal sequence analysis of the various glycoproteins suggest that at 32 degrees C a G protein containing a single glycosidic moiety is synthesized. The G protein containing only 1 oligosaccharide residue is transported to the cell surface and is incorporated in infectious virus particles. In contrast, the G protein synthesized at 39 degrees C is nonglycosylated and fails to reach the cell surface. These results suggest that glycosylation of G protein is essential for its transport to the cell surface, and the presence of a single carbohydrate chain is sufficient for this purpose.
水泡性口炎病毒科卡尔血清型的温度敏感突变体（ts gamma 1）在允许温度（32摄氏度）下合成一种糖蛋白G，其大小比野生型（Mr 71,000）小（Mr 68,000），并且使病毒粒子对热不稳定。在非允许温度（39摄氏度）下，产生了数量减少的缺乏G蛋白的无感染性病毒样颗粒。在非允许温度下，细胞内G蛋白的大小进一步减小（Mr 64,000）。包括糖标记、胰蛋白酶肽分析和各种糖蛋白的氨基末端序列分析在内的生化研究表明，在32摄氏度时合成了一种含有单个糖苷部分的G蛋白。仅含有1个寡糖残基的G蛋白被转运到细胞表面并被整合到感染性病毒颗粒中。相比之下，在39摄氏度时合成的G蛋白未被糖基化，无法到达细胞表面。这些结果表明，G蛋白的糖基化对于其转运到细胞表面至关重要，并且单个碳水化合物链的存在足以实现这一目的。
