Figure 2. miR-450b-3p directly targets 3′ UTR of HER3 and its downstream pathways. (A) Structures of the plasmid pGL3-promoter-HER3-3′ UTR. The whole HER3 3′ UTR (wild type or mutant) was fused to the immediate downstream of firefly luciferase cDNA in pGL3-promoter (Promega) to yield pGL3-promoter-HER3-3′ UTR wild type or mutant. (B) The luciferase activity of pGL3-promoter-HER3-3′ UTR wild type or mutant was measured in presence of scrambled miRNA or miR-450b-3p precursor. The renilla luciferase activity was used as the transfection control. The data was calculated from three independent experiments. Bars, SD. *, significantly different compared with scrambled control (P < 0.05). (C) The SKBR3 cells were transfected with pSUPER or increasing amount of pSUPER-miR-450b-3p for 36 h, and indicated molecules were analyzed by western blot. The results are representative of three independent experiments. Bars, SD. *, # and §, significantly different compared with scrambled control (P < 0.05).