目的 探讨信号转导接头蛋白2 (STAP2)和输入蛋白5 (Ipo5)表达对骨骼肌蛋白质周转的影响。方法 12只雄性Sprague-Dawley大鼠随机分入对照组(n=6)和模型组(n=6)。对照组不处理,模型组采用阻血诱导大鼠骨骼肌肥大。体外培养两组比目鱼肌细胞,模型组细胞用shRNA慢病毒感染细胞,先后实现基因STAP2、Ipo5沉默、过表达和功能挽救。Western blotting检测两组细胞STAP2、Ipo5和myostatin蛋白表达。结果 模型组较对照组STAP2表达显著上升(t=-11.786, P<0.001),Ipo5和myostatin表达下降(t>14.039, P<0.001);在对照组、模型组、沉默组、过表达组、挽救组中,myostatin表达随STAP2表达降低而升高,随Ipo5表达升高而升高。结论 STAP2表达上调和Ipo5表达下降可促进蛋白质合成。
Objective To explore the expression of signal-transducing adaptor protein 2 (STAP2) and importin 5 (Ipo5), and the effect of them on skeletal muscle protein turnover. Methods Twelve male Sprague-Dawley rats were divided into control group (n=6) and model group (n=6). The model group established skeletal muscle hypertrophy induced by blood flow restriction. The soleus muscle cells in both groups were cultured in vitro, and those in the model group infected with shRNA lentivirus to make the expression of STAP2 and Ipo5 silencing, over-expression and gene function salvage finally. The expression of STAP2, Ipo5 and myostatin were determined with Western blotting in soleus muscle in both groups.Results The expression of STAP2 increased (t=-11.786, P<0.001), while the expression of Ipo5 and myostatin decreased (t>14.039, P<0.001) in the model groups compared with those in the control group. Under the control group and the model group, and target genes silencing group, overexpressing group and rescuing group, the expression of myostatin increased with STAP2 decrease and Ipo5 increase.Conclusion The expression of STAP2 increasing and Ipo5 decreasing would promote the protein synthesis.
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