Role of cotranslational disulfide bond formation in the folding of the hemagglutinin-neuraminidase protein of Newcastle disease virus.
Role of cotranslational disulfide bond formation in the folding of the hemagglutinin-neuraminidase protein of Newcastle disease virus.
复制标题
共翻译二硫键形成在新城疫病毒血凝素-神经氨酸酶蛋白折叠中的作用。
DOI：
10.1006/viro.1996.0553
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发表时间：
1996
期刊：
影响因子：
--
通讯作者：
Morrison,TG
中科院分区：
文献类型：
--
作者：
McGinnes,LW;Morrison,TG
探讨了共翻译二硫键形成在纽卡斯尔病毒血凝素-神经氨酸酶（HN）糖蛋白折叠途径中的作用。在存在或不存在还原剂的情况下的脉冲标记的HN蛋白的电泳表明，许多糖蛋白的特征，新生HN蛋白含有分子内二硫键。正如Braakmanet al. (EMBO J. 11，1717-1722，1992），在二硫苏糖醇（DTT）中孵育细胞阻断了这些键的形成。去除DTT后的脉冲标签允许随后形成的分子内二硫键和分子的折叠，如通过构象敏感的抗原位点的出现和通过形成二硫键连接的二聚体所测定的。然而，在DTT存在下合成后形成构象敏感抗原位点的θ 1/2是对照的两倍以上。此外，抗原位点的出现顺序与对照不同，表明抑制共翻译二硫键形成改变了蛋白质的折叠途径。在含有膜的无细胞系统中获得了类似的结果。HN蛋白被迫形成的分子内二硫键posteradionally没有检测到的神经氨酸酶或细胞附着活性，这表明该蛋白质有一个异常的构象。
The role of cotranslational disulfide bond formation in the folding pathway of the hemagglutinin-neuraminidase (HN) glycoprotein of Newcastle disease virus was explored. Electrophoresis of pulse-labeled HN protein in the presence or absence of reducing agent showed that, characteristic of many glycoproteins, the nascent HN protein contains intramolecular disulfide bonds. As reported by Braakmanet al.(EMBO J.11, 1717–1722, 1992), incubation of cells in dithiothreitol (DTT) blocked the formation of these bonds. Removal of DTT after a pulse-label allowed for the subsequent formation of intramolecular disulfide bonds and folding of the molecule as assayed by the appearance of conformationally sensitive antigenic sites and by the formation of disulfide-linked dimers. However, thet1/2for the formation of a conformationally sensitive antigenic site after synthesis in the presence of DTT was over twice that of the control. Furthermore, the order of appearance of the antigenic sites was different from the control, suggesting that inhibition of cotranslational disulfide bond formation altered the folding pathway of the protein. Similar results were obtained in a cell-free system containing membranes. The HN protein forced to form intramolecular disulfide bonds posttranslationally had no detectable neuraminidase or cell attachment activity, suggesting that the protein had an abnormal conformation.