Nishida E, Tobe K, Kadowaki T, Kasuga M, Sato C, Sakai H
Department of Biophysics and Biochemistry, Faculty of Science, University of Tokyo, Japan.
Cell Struct Funct. 1988 Oct;13(5):417-23. doi: 10.1247/csf.13.417.
Insulin-like growth factor-I (IGF-I) stimulated the phosphorylation of cytoskeletal 350-kDa and 300-kDa proteins which were immunoprecipitated with antibodies against brain high molecular weight microtubule-associated proteins in quiescent rat 3Y1 cells. The data on the effective concentrations of IGF-I and 125I-labeled IGF-I binding indicated that type I IGF receptors mediate this IGF-I effect. Platelet-derived growth factor (PDGF) as well as phorbol ester (TPA) also stimulated the phosphorylation of these proteins. These proteins, whether immunoprecipitated from cells stimulated by insulin, IGF-I, TPA, PDGF, or epidermal growth factor, produced very similar phosphopeptide mapping patterns irrespective of the stimulant. The results suggest the possibility that these growth factors and phorbol esters may activate a common protein kinase which is responsible for the phosphorylation of the 350-kDa and 300-kDa proteins in cells.
胰岛素样生长因子-I（IGF-I）刺激了350-kDa和300-kDa细胞骨架蛋白的磷酸化，这些蛋白是用针对静止大鼠3Y1细胞中脑高分子量微管相关蛋白的抗体进行免疫沉淀得到的。关于IGF-I有效浓度和125I标记的IGF-I结合的数据表明，I型IGF受体介导了这种IGF-I效应。血小板衍生生长因子（PDGF）以及佛波酯（TPA）也刺激了这些蛋白的磷酸化。这些蛋白，无论从受胰岛素、IGF-I、TPA、PDGF或表皮生长因子刺激的细胞中免疫沉淀得到，无论刺激物是什么，都产生非常相似的磷酸肽图谱。结果表明，这些生长因子和佛波酯可能激活一种共同的蛋白激酶，该激酶负责细胞中350-kDa和300-kDa蛋白的磷酸化。
