Glenney J R
Lucille P. Markey Cancer Center, Department of Biochemistry, University of Kentucky College of Medicine, Lexington 40536-0093.
J Biol Chem. 1989 Dec 5;264(34):20163-6.
Recent studies from this laboratory have identified novel cytoskeletal proteins that are phosphorylated on tyrosine in vivo in Rous sarcoma virus-transformed chick fibroblasts (Glenney, J. R., Jr., and Zokas, L. (1989) J. Cell Biol. 108, 2401-2408). In the present report, the phosphorylation of these proteins was examined in cells expressing the nonmyristylated mutants of src that are not transformed. A good correlation was found between transformation and the tyrosine phosphorylation of a 22-kDa protein. Tyrosine phosphorylation of the 22-kDa protein was reduced more than 95% in cells expressing the nonmyristylated mutants of src. Size fractionation revealed that the 22-kDa phosphoprotein in transformed chick fibroblasts is found in a Mr 150,000 complex. Monoclonal antibodies were used to screen various chicken tissues where the 22-kDa protein was found at high levels in muscle and lung with low levels in epithelial cells and brain. The 22-kDa protein becomes an excellent candidate for a mediator of transformation by the tyrosine kinase class of oncogenes.
该实验室最近的研究鉴定出了新的细胞骨架蛋白，这些蛋白在劳氏肉瘤病毒转化的鸡成纤维细胞中发生了体内酪氨酸磷酸化（Glenney, J. R., Jr., and Zokas, L. (1989) J. Cell Biol. 108, 2401 - 2408）。在本报告中，对这些蛋白的磷酸化情况在表达未转化的src非肉豆蔻酰化突变体的细胞中进行了检测。发现转化与一种22 kDa蛋白的酪氨酸磷酸化之间存在良好的相关性。在表达src非肉豆蔻酰化突变体的细胞中，22 kDa蛋白的酪氨酸磷酸化减少了95%以上。大小分级分离显示，转化的鸡成纤维细胞中的22 kDa磷蛋白存在于一个Mr 150,000的复合物中。使用单克隆抗体筛选各种鸡组织，发现22 kDa蛋白在肌肉和肺中含量高，在上皮细胞和脑中含量低。22 kDa蛋白成为酪氨酸激酶类癌基因转化介导因子的极佳候选者。
