(a) Structure of psiCHECK-SM, which has three tandem repeats in the Renilla
luciferase 3′ UTR. (b) Structure of psiCHECK-CM, which has a complete-matched target
sequence in the Renilla luciferase 3′ UTR. (c) The miRNA-mediated gene-silencing
activities in HeLa cells as a function of miRNA concentration at 0.05, 0.5, and 5 nM.
The indicated concentration of synthetic miRNA, psiCHECK-SM construct (10 ng), and
pGL3-control (100 ng) were simultaneously transfected into HeLa cells, and
Renilla luciferase activity / firefly luciferase activity was determined
24 hours after transfection. The gene-silencing efficiencies of target mRNA varied
significantly depending on the miRNA duplex used for transfection. The sequences of
miRNAs and target mRNAs are shown in Figure S1. The ordinate
represents relative luciferase activity (%) and the abscissa represents miRNA
concentration. The black bar indicates the result of psiCHECK-SM. The white bar, the
result of psiCHECK-CM.