Burns L A, Karnitz L M, Sutor S L, Abraham R T
Department of Immunology, Mayo Clinic and Foundation, Rochester, Minnesota 55905.
J Biol Chem. 1993 Aug 25;268(24):17659-61.
Stimulation of activated T cells with interleukin-2 (IL-2) results in the tyrosine phosphorylation of several intracellular proteins. The present studies demonstrate that IL-2 stimulation induces phosphorylation of the src homology 2 domain-containing protein, p52shc, on both tyrosine and serine residues. The level of p52shc phosphorylation was maximal within 5 min after growth factor addition and declined gradually thereafter. In addition, anti-Shc immunoprecipitates from IL-2-stimulated T cells contained a co-precipitating protein tyrosine kinase (PTK) activity that phosphorylated p52shc on tyrosine residues in immune complex kinase assays. These results demonstrate that p52shc is an early substrate for IL-2 receptor-coupled PTK activity(s) and suggest that this protein may be involved in the transduction of PTK-dependent regulatory signals in IL-2-stimulated T cells.
用白细胞介素-2（IL-2）刺激活化的T细胞会导致几种细胞内蛋白质发生酪氨酸磷酸化。目前的研究表明，IL-2刺激会诱导含src同源2结构域的蛋白p52shc的酪氨酸和丝氨酸残基发生磷酸化。生长因子添加后5分钟内，p52shc的磷酸化水平达到最大值，此后逐渐下降。此外，来自IL-2刺激的T细胞的抗Shc免疫沉淀产物含有一种共沉淀的蛋白酪氨酸激酶（PTK）活性，在免疫复合物激酶分析中，该活性可使p52shc的酪氨酸残基发生磷酸化。这些结果表明，p52shc是IL-2受体偶联的PTK活性的早期底物，并提示该蛋白可能参与IL-2刺激的T细胞中PTK依赖性调节信号的转导。
