Figure 2. Drosha is involved in destabilizing LRE-containing reporter mRNA. HEK293 cells were transfected with siCon, siDrosha or siDicer. Forty-two hours post-siRNA transfection, a second transfection with reporter constructs (see below) was performed. RNA and protein were then extracted 18 h after the second transfection and levels determined by RT-qPCR (A, C and D) and western blotting (B and E), respectively. (A and D) Relative levels of indicated endogenous mRNAs are presented with levels from siCon-transfected cells arbitrarily set as 1. (B and E) Western blot results using specific antibodies indicated on the right. Beta-tubulin was used as loading control. (C) Effects of Drosha or Dicer knockdown on luciferase reporter mRNA levels. HEK293 cells were first transfected with siCon, siDrosha or siDicer, and second with each indicated report construct as described above. RNAs were extracted 18 h after the second transfection and analyzed by RT-qPCR. Relative luciferase mRNA levels are presented with mutant LRE-containing luciferase mRNA levels arbitrarily set as 1. Numbers are mean ± SD (n = 3). * p < 0.05; ** p < 0.01.