Tyrosine phosphorylation of alpha-tubulin is an early response to NGF and pp60v-src in PC12 cells.
Tyrosine phosphorylation of alpha-tubulin is an early response to NGF and pp60v-src in PC12 cells.
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α-微管蛋白的酪氨酸磷酸化是 PC12 细胞中对 NGF 和 pp60v-src 的早期反应。
DOI：
10.1007/bf02782119
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发表时间：
1993
期刊：
影响因子：
--
通讯作者：
Maness,PF
中科院分区：
文献类型：
--
作者：
Cox,ME;Maness,PF
神经元分化伴随着细胞骨架的广泛重组以启动神经炎过程的延伸。我们已经使用大鼠PC 12嗜铬细胞瘤细胞系研究蛋白酪氨酸激酶活性在诱导这些事件中的作用。磷酸酪氨酸抗体免疫印迹显示，在PC 12细胞中的α-微管蛋白的酪氨酸磷酸化发生在神经生长因子（NGF）处理10分钟内。在一个含有小鼠金属硫蛋白酶I基因启动子转录控制下的诱导型v-src基因的PC 12细胞系（PC 12-B 9）中，α-微管蛋白的酪氨酸磷酸化也发生在pp 60 v-src表达的诱导过程中。在NGF和pp 60 v-src诱导的PC 12细胞中，两种酪氨酸磷酸化蛋白质与α-微管蛋白在双向电泳上共迁移，用磷酸化酪氨酸抗体免疫沉淀，然后用α-微管蛋白特异性单克隆抗体免疫印迹，鉴定为α-微管蛋白亚型。这些结果表明，α-微管蛋白是一种体内酪氨酸激酶底物，其在PC 12细胞神经元分化途径中响应于NGF或pp 60 v-src而被磷酸化作为早期事件。可以想象，α-微管蛋白的酪氨酸磷酸化可以改变神经突延伸诱导过程中的微管动力学。
Neuronal differentiation is accompanied by extensive reorganization of the cytoskeleton to initiate the extension of neuritic processes. We have used the rat PC12 pheochromocytoma cell line to examine the role of protein tyrosine kinase activity in the induction of these events. Immunoblotting with phosphotyrosine antibodies revealed that tyrosine phosphorylation of α-tubulin in PC12 cells occurred within 10 min of nerve growth factor (NGF) treatment. Tyrosine phosphorylation of α-tubulin also occurred on induction of pp60v-srcexpression in a PC12 cell line (PC12-B9) harboring an inducible v-srcgene under transcriptional control of the mouse metallothionine I gene promoter. Two tyrosine phosphorylated proteins in NGF-and pp60v-srcinduced PC12 cells were identified as α-tubulin isoforms by comigration with α-tubulin on two-dimensional gel electrophoresis, and by immunoprecipitation with phosphotyrosine antibodies followed by immunoblotting with a monoclonal antibody specific for α-tubulin. These results demonstrate that α-tubulin is an in vivo tyrosine kinase substrate, which is phosphorylated as an early event in the neuronal differentiation pathway of PC12 cells in response to NGF or pp60v-src. Tyrosine phosphorylation of α-tubulin could conceivably alter microtubule dynamics during induction of neurite extension.