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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