胰岛素受体的分离纯化及其酪氨酸蛋白激酶特性的研究

本文利用差速离心,2%Triton X-100增溶,伴刀豆球蛋白A-琼脂糖,胰岛素-亲和胶及麦胚凝集素-亲和胶亲和层析分离纯化了人胎盘的胰岛素受体。纯化的受体经圆盘电泳及HPLC凝胶过滤得单一峰。SDS-电泳显示分子量分别为135000及90000的两条带。纯受体有自身磷酸化作用,且对外源性底物呈现酪氨酸蛋白激酶活性。有意义地是纯化的受体的磷酸化可受促癌剂促癌因子抑制。

PURIFICATION OF INSULIN RECEPTOR AND CHARACTERIZATION OF ITS PROTEIN KINASE

Insulin receptors have been purified from human placenta by differential centrifugation solubilization in 2% Triton X-100 affinity chromatography on Co-ncanavalin A-sepharose,Insulin-Affi gel,and WGA-Affi gel.The purified insulin receptors were found to give a single band in Disc polyacrylamidc electrophoresis and gel filtration in HPLC. Two bands with Mr of 135 000 and 90 000 were revealed on SDS polyacrylamide electrophoresis. The preparation showed tyro-sine kinase activity towards exogenous substrate and autophosphorylation.It was interesting to note that the phosphorylation of the purified receptor was inhi-bited by TPA.