Ishii T, Sugamura K, Nakamura M, Hinuma Y
Biochem Biophys Res Commun. 1986 Mar 13;135(2):487-94. doi: 10.1016/0006-291x(86)90020-3.
We have investigated interleukin 2 (IL-2)-induced protein phosphorylation in an IL-2 dependent murine cell line by the two-dimensional gel electrophoresis. IL-2 rapidly and markedly induced phosphorylation of a cellular protein distinct from the IL-2 receptor, with a molecular weight of 67,000 daltons and an isoelectric point of 5.8, named pp67. IL-2 dose-responses of pp67 phosphorylation and cell proliferation were well correlated. Phosphoamino acid analysis showed that the phosphorylation site of pp67 was a serine residue. Further, when the cells were treated with 12-O-tetradecanoylphorbol-13-acetate (TPA) instead of IL-2, similar increase of pp67 phosphorylation was observed. Such IL-2 dependent protein phosphorylation was also detected in various human IL-2 receptor bearing T cells. Thus we speculate that the phosphorylation of pp67 could be regulated by protein kinase C and it could be a common feature in an early event of the intracellular growth signaling from the IL-2 receptor.
我们通过二维凝胶电泳研究了白细胞介素2（IL-2）在一种依赖IL-2的小鼠细胞系中诱导的蛋白质磷酸化。IL-2迅速且显著地诱导了一种不同于IL-2受体的细胞蛋白的磷酸化，该蛋白分子量为67,000道尔顿，等电点为5.8，命名为pp67。pp67磷酸化的IL-2剂量反应与细胞增殖密切相关。磷酸氨基酸分析表明，pp67的磷酸化位点是一个丝氨酸残基。此外，当用12-O-十四烷酰佛波醇-13-乙酸酯（TPA）而非IL-2处理细胞时，观察到pp67磷酸化有类似增加。在各种表达人IL-2受体的T细胞中也检测到了这种依赖IL-2的蛋白质磷酸化。因此我们推测，pp67的磷酸化可能受蛋白激酶C调节，并且它可能是IL-2受体细胞内生长信号传导早期事件中的一个共同特征。
