【摘要】 目的探讨成骨样细胞MG-63中c-fos基因和细胞骨架丝状肌动蛋白(F-actin)的相互关系。方法对MG-63细胞施加周期性张应力,频率为0.5 Hz,细胞应变为2 000μstrain,按3、6、12 h不同时间段进行加载,采用荧光定量聚合酶链反应(PCR)检测c-fos mRNA的变化,筛选最佳加载时间点,并作为实验组和0 h组进行对比,检测在细胞松弛素D作用下c-fos mRNA和F-actin的表达变化。结果周期性张应力可以诱导c-fos mRNA的表达增加,至3 h达到峰值;在周期性张应力作用下,MG-63细胞中F-actin的结构、排列发生改变,但荧光强度无明显变化;经细胞松弛素D处理后,张应力作用下的MG-63细胞的应力纤维明显减少,F-actin荧光强度降低,c-fos mRNA表达受抑制。结论周期性张应力作用下,F-actin的量并没有明显变化,只是出现了结构上的重组,且重组的是既有的F-actin。F-actin重组是应力诱导c-fos基因高表达的一个重要环节。更多还原

【Abstract】 Objective To investigate the relationship between c-fos gene and filamentous actin(F-actin) in MG63 osteoblasts under cyclic tensile stress.Methods MG-63 osteoblasts were subjected to cyclic tensile stress(0.5 Hz, 2 000 μstrain) for 3,6,and 12 h.The changes of c-fos gene were investigated by fluorescent quantitation polymerase chain reaction.Then the best loading time group was screened as the experimental group compared with 0 h group.The changes of F-actin and c-fos were investigated with or without cytochalasin D treatment.Results Cyclic tensile stress induced high expression of c-fos mRNA,and peaked at 3 h.After loading,F-actin had a structure reorgani-zation,but had no change in expression.After cytochalasin D treatment,the formation of stress fibers and the fluo-rescence intensity of F-actin cytoskeleton significantly reduced,meanwhile the c-fos mRNA expression was inhibited.Conclusion After loading,there is only structure reorganization for F-actin,and the expression has not any change.That means the remodeling F-actin is the existing one.F-actin reorganization is an important part in c-fos gene ex-pression induced by stress.更多还原