Shiu R P, Pastan I H
Biochim Biophys Acta. 1979 Jan 25;576(1):141-50. doi: 10.1016/0005-2795(79)90493-8.
A glucose-regulated protein of molecular weight 78,000 (GRP-78) had been purified from a membrane fraction isolated from viral transformed chick embryo fibroblasts. Purification was achieved by extraction of the membrane fraction with Triton X-100, and chromatography on diethylaminoethyl-cellulose and hydroxyapatite. The purified protein exhibited one single spot on two-dimensional polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate and has a pI of about 5.3. A monospecific antiserum to GRP-78 was generated in a goat. Immunofluorescence studies using affinity purified antibodies to GRP-78 revealed that this protein was not exposed on the cell surface but was localized in a granular vesicular network inside the cell that resembles the distribution of endoplasmic reticulum. The availability of purified GRP-78 and a specific antiserum to it should prove useful in elucidating the role of this protein in glucose metabolism and its relationship to malignant transformation.
一种分子量为78,000的葡萄糖调节蛋白（GRP-78）已从病毒转化的鸡胚成纤维细胞分离得到的膜组分中纯化出来。通过用Triton X-100提取膜组分，并在二乙氨基乙基纤维素和羟基磷灰石上进行层析来实现纯化。在十二烷基硫酸钠存在的情况下，纯化后的蛋白质在二维聚丙烯酰胺凝胶电泳上呈现出一个单一斑点，其pI约为5.3。在山羊体内产生了针对GRP-78的单特异性抗血清。使用针对GRP-78的亲和纯化抗体进行的免疫荧光研究表明，这种蛋白质并未暴露在细胞表面，而是定位在细胞内类似内质网分布的颗粒状囊泡网络中。纯化的GRP-78及其特异性抗血清的可得性应有助于阐明该蛋白在葡萄糖代谢中的作用及其与恶性转化的关系。
