【摘要】 本试验利用实时定量RT-PCR、酪蛋白底物酶原分析和SDS-PAGE等方法研究不同浓度钙离子对分化的大鼠L6成肌细胞中μ-calpain mRNA蛋白水平表达以及对L6细胞内蛋白的降解程度的影响。研究表明:钙离子处理可以诱导L6进一步分化为肌管,高浓度钙离子(>1000μM)还导致L6死亡率增大;钙离子诱导μ-calpain mRNA和蛋白水平表达增加。钙离子浓度为1000μM时,μ-capain mRNA的表达量为对照组的3倍多,但是当钙离子浓度升至1500μM时表达量却降低。50-100μM钙离子可以使μ-calpain酶活增加两倍,而500-1500μM钙离子增加酶活5-7倍;高浓度钙离子由于提高了μ-capaln的活性,细胞内蛋白的降解代谢增强,在SDS-PAGE凝胶电泳中发现细胞上清液中有明显的蛋白条带出现。更多还原

【Abstract】 The effects of calclum ion On theμ—calpain expression in mRNA and proteinevels of rat L6 myoblast were investigated using real—time quantatitive RT-PCR,SDS—PAGE electrophoresis and caseirzy mographic analy sis.The results reveaed Ca2+could induce the differentialion of L6 myoblasr,and high levet Ca2+(>1000μM)could lead to L6 death.mRNA expression of μ—calpain was increased when Ca2+ was added to L6.Furthermore,μ—calpaln mRNA expression evaluated by real-time quantatitive RT-PCR increased more than 3 times treated with 1000μM Ca2+,compared to Ca2+free contro L6 cells.While,the mRNA expression decreased when calcium ion increased to 1500μM.μ-calpain activity increased more than 2 and 5-7times with 50—100,and 500-1500μM Ca2+treatment compared with the control group.In addition,L6 cellular protein degradation was enhanced by Ca2+stimulation as the result of increasedμ-calpain activity.To conclude,Ca2+can activeμ-calpain and improve μ-calpain expression both in mRNA and protein levels.更多还原