Effect of siRNA on mcl-1 expression in HepG2 cells

AIM: To investigate the effect of specific siRNA on mcl-1 expression in hepatoma cell line HepG2. METHODS: Human hepatoma cell line HepG2 was cultured in vitro and transfected with two siRNAs(different loci) of mcl-1 by lipofectamine 2000. The levels of mcl-1 mRNA expression before and after transfection were detected by semi-quantitative reverse transcription polymerase chain reaction(RT-PCR).The interfering effect between the two siRNAs and the specificity and time effect for interference were compared.Then the levels of Mcl-1 protein expression before and after transfection were detected by Western Blot. RESULTS: The level of mcl-1 mRNA in HepG2 cells was inhibited by the specific siRNAs.The expression of mcl-1 mRNA began to decrease 24 h after transfection; and the most apparent interfering efficiency was 67.25% 48 h after transfection,which was markedly higher than that in the cells transfected with the control siRNAs; at 72 h, the expression restored a little. Both siRNAs(siRNA-F1 and siRNA-F2)from different loci had interfering effect on mcl-1 mRNA expression, and there was only a little difference between them.Western Blot indicated that the expression of Mcl-1 protein was downregulated in HepG2 cells after interfered with siRNA-F1. CONCLUSION: RNA interference can downregulate the level of mcl-1 mRNA in HepG2 cells.And Mcl-1 protein expression is also downregulated by specific siRNA.