Klein H H, Freidenberg G R, Cordera R, Olefsky J M
Biochem Biophys Res Commun. 1985 Feb 28;127(1):254-63. doi: 10.1016/s0006-291x(85)80152-2.
The abilities of insulin and EGF stimulated protein kinases to phosphorylate a series of exogenous substrates were compared using wheat germ lectin purified preparations of solubilized rat liver membranes. Three different kinds of substrates were found: substrates phosphorylated primarily by insulin stimulated kinase, substrates phosphorylated primarily by EGF stimulated kinase and substrates phosphorylated by both kinases to a similar extent. These results indicate that the insulin and the EGF receptor kinase have different, but overlapping, substrate specificities. In vivo, phosphorylation of cellular proteins by various hormone receptor kinases may be part of the signal transmission process for actions of the hormones. Different substrate specificities of kinases of different hormone receptors may therefore represent an important mechanism to preserve the specificity of the hormonal signal at the post receptor level.
利用小麦胚凝集素纯化的溶解大鼠肝细胞膜制剂，比较了胰岛素和表皮生长因子（EGF）刺激的蛋白激酶磷酸化一系列外源底物的能力。发现了三种不同类型的底物：主要由胰岛素刺激的激酶磷酸化的底物、主要由EGF刺激的激酶磷酸化的底物以及由两种激酶磷酸化程度相似的底物。这些结果表明，胰岛素和EGF受体激酶具有不同但重叠的底物特异性。在体内，各种激素受体激酶对细胞蛋白的磷酸化可能是激素作用信号传递过程的一部分。因此，不同激素受体激酶的不同底物特异性可能代表了在受体后水平保持激素信号特异性的重要机制。
