持续性压力通过影响ERK1/2和GIT1的结合促进大鼠成骨细胞的迁移

目的:探讨持续压力对体外培养的大鼠成骨细胞内ERK1/2及GIT1蛋白相互关系及对大鼠成骨细胞迁移能力的影响.方法:取1～2天龄SD大鼠颅盖顶骨进行成骨细胞原代培养,采用压缩空气在密闭容器内对第2代细胞施以300 kPa的静压力,分别于未加压,加压后0.5、1.0、2.0 h提取细胞总蛋白,Western blot检测各组成骨细胞在Src抑制剂PP2不干预和干预下ERK1/2和GIT1的表达及其磷酸化,免疫共沉淀分析GIT1同活化的ERK1/2(phospho-ERK1/2,pERK1/2)相互作用的变化.Image-Pro Plus 5.0软件检测成骨细胞在Src抑制剂PP2不干预和干预下加压前后面积.结果:Western blot结果显示pERK1/2和pGIT1的表达在持续加压组较对照组明显增加;PP2干预下持续加压组的成骨细胞内的pERK1/2和pGIT1的表达较对照组无统计学差异;免疫共沉淀结果显示GIT1-pERK1/2结合力在持续加压组较对照组明显增加;持续加压后成骨细胞面积明显增加:PP2干预下持续加压后成骨细胞面积较对照组无统计学差异.结论:300 kPa左右的持续性压力能通过激活Src的活性,从而诱导ERK1/2,GIT1的磷酸化,同时增加pERK1/2和GIT1的相互结合,促进大鼠成骨细胞的迁移,Src-GIT1/ERK1/2途径可能是成骨细胞力学信号转导过程中的重要通路之一.

The role of GIT1 and ERK1/2 of osteoblast migration induced by durative pressure

Objective:To investigate the role and mechanism of G-protein-coupled receptor kinase interacting protein 1(GIT1)and extracellular signal-regulated kinases 1 and 2 (ERK1 / 2)in osteoblasts induced by durative pressure. Methods:The osteoblasts were mechanically stimulated on coverslips. The phosphorylation of ERK1 / 2 and GIT1 of osteobasts treated with or without the Src kinase inhibitor PP2 was measured by Western blot. The interaction between GIT1 and pERK1 / 2 was detected by coimmunoprecipitation. Cell a...