The effects of wheat germ agglutinin on the adipocyte insulin receptor.
The effects of wheat germ agglutinin on the adipocyte insulin receptor.
复制标题
小麦胚芽凝集素对脂肪细胞胰岛素受体的影响。
DOI：
10.1016/0304-4165(81)90206-3
复制
发表时间：
1981
期刊：
影响因子：
--
通讯作者：
Purvis,BJ
中科院分区：
文献类型：
--
作者：
Livingston,JN;Purvis,BJ
用麦胚凝集素处理大鼠脂肪细胞通过增加胰岛素受体的亲和力而显著增强胰岛素结合。通过柱层析和聚丙烯酰胺凝胶电泳研究了麦胚凝集素处理后脂肪细胞受体的结构，以确定是否存在胰岛素受体的聚集体。用Triton X-100溶解受体并使该物质通过Sepharose 6 B显示出两种胰岛素结合活性：一个主峰的Stokes半径为87 nm，一个次峰的Stokes半径为47 nm。麦胚凝集素处理产生的两个峰的结合活性的增加，但它们的分子量没有改变。此外，125 I标记的胰岛素通过交联剂共价连接到脂肪细胞胰岛素结合位点。胰岛素-受体复合物的柱层析再次表明存在两种物质，斯托克斯半径分别为87 nm和47 nm。在这些复合物中的杂合酶也证明了在Triton X-100的存在下，通过聚丙烯酰胺凝胶电泳。Ferguson图表明放射性峰的分子半径为60 nm，这是在存在和不存在小麦胚芽处理脂肪细胞时发现的大小。这些发现表明，小麦胚芽凝集素处理产生的受体亲和力的增加不是由受体簇的形成引起的。相反，似乎植物凝集素和受体之间的简单相互作用足以诱导脂肪细胞的胰岛素结合特性的变化。
Treatment of rat adipocytes with wheat germ agglutinin markedly enhances insulin binding by increasing the affinity of the insulin receptor. The structure of the adipocyte receptor following wheat germ agglutinin treatment was studied by column chromatography and polyacrylamide gel electrophoresis to determine if aggregates of the insulin receptor are present. Solubilization of the receptor by Triton X-100 and passage of this material over Sepharose 6B revealed two insulin binding activities: a major peak which has a Stokes radius of 87 Å and a minor peak with a Stokes radius of 47 Å. Wheat germ agglutinin treatment produced an increase in the binding activity of both peaks, but their molecular weights did not change. In addition,125I-labeled insulin was covalently attached to the adipocyte insulin binding sites by a cross-linking reagent. Column chromatography of the insulin-receptor complex again indicated the presence of two species with Stokes radii of 87 Å and 47 Å. Heterogeneity in these complexes was also demonstrated by polyacrylamide gel electrophoresis in the presence of Triton X-100. Ferguson plots indicated that the peak of radioactivity had a molecular radius of 60 Å, a size found both in the presence and absence of wheat germ treatment of adipocytes. These findings suggest that the increase in receptor affinity produced by wheat germ agglutinin treatment is not caused by the formation of receptor clusters. Instead, it appears that a simple interaction between the plant lectin and the receptor is sufficient to induce the changes in the insulin binding properties of adipocytes.