ERK在NGF诱导PC12细胞分化中的作用  

Role of ERK in PC12 cells Induced by differentiation NGF

作　　者：张雯[1] 彭芳芳[1] 张百芳[1] 沈晗[1] 吴少波[1] 武栋成[1] 

机构地区：[1]武汉大学医学院生物化学与分子生物学系,湖北武汉430071

出　　处：《基础医学与临床》2005年第3期227-231,共5页Basic and Clinical Medicine

基　　金：国家自然科学基金(30170335)

摘　　要：目的探讨细胞外信号调节激酶(ERK)在NGF诱导的PC12细胞分化中的作用机制。方法以NGF处理PC12细胞建立分化模型,运用免疫印迹检测不同浓度不同作用时间时NGF对ERK1/2蛋白和磷酸化ERK1/2蛋白水平的影响,并观察MAPK/ERK激酶(MEK)抑制剂U0126对NGF诱导的细胞形态学改变的影响。结果ERK1/2蛋白的磷酸化呈现NGF剂量和时间依赖性。NGF作用细胞5min即可观察到明显的ERK1/2蛋白磷酸化,持续1h左右,2h时降低到初始水平,而细胞形态的改变出现在NGF作用12h以后。倒置相差显微镜观察可见PC12细胞分化的程度与ERK1/2活化持续的时间正相关,U0126可完全即时抑制ERK1/2的活化,而ERK1/2活化的抑制可完全阻断NGF诱导的PC12细胞分化。结论ERK1/2的活化是PC12细胞发生分化的必需事件,其活化时间的长短对分化具有决定作用。Objective To decide whether the extracellular signal-regulated kinase (ERK) play a crucial role in PC12 differentiation induced by nerve-growth factor (NGF). Methods Cells were treated with NGF, and cell extracts were subjected to immunobblotting with antibodies against ERK1/2 and pp-ERK1/2. To more clearly define the role of ERK1/2, a small molecule inhibitor of MAPK/ERK kinase named U0126 was examined for its effect on the cellular action of NGF in PC12 cells. Results We showed that NGF induced sustained activation of ERK1/2 in 1 h. In the presence of U0126, however, NGF-induced differentiation were no longer observed and the expression of pp-ERK1/2 was severely impaired. Conclusion Our results indicated that sustained activation of ERK1/2 in the early stage of cell differentiation is necessary for NGF-induced neurite outgrowth, and the differentiation was markedly regulated by NGF treatment through activation of the ERK1/2 pathway. In a word, activation of ERK1/2 is essential to neuronal differentiation of PC12 cells.

关 键 词：细胞分化 NGF ERK1/2 细胞外信号调节激酶 细胞形态学改变 PC12细胞 免疫印迹检测 ERK激酶 时间依赖性 蛋白磷酸化 作用机制 分化模型 蛋白水平 作用时间 不同浓度 MAPK 微镜观察 细胞发生 决定作用 2蛋白 活化 抑制剂 NCF 正相关 

分 类 号：R329.2[医药卫生—人体解剖和组织胚胎学] R651.3[医药卫生—基础医学]