Fig. 3.

miR-221 targets ICAM-1 3′-untranslated region (UTR) and causes posttranscriptional suppression. A: human ICAM-1 mRNA shows a potential binding site in the 3′UTR for miR-221. B: targeting of ICAM-1 3′UTR by miR-221 resulted in transcriptional suppression. The luciferase reporter constructs containing the potential binding site for miR-221 in ICAM-1 3′UTR or the mutant (Mut) sequence (TGTAGC to ACATCG) were generated. H69 cells were transiently cotransfected with the reporter construct and the miR-221 precursor or anti-miR-221 for 24 h. Luciferase activities were measured and normalized to the control (Ctrl) β-galactosidase (β-gal) level. A nonspecific precursor (precursor-Ctrl) and anti-miR (anti-miR-Ctrl) were used as the controls. Bars represent the means ± SD from 3 independent experiments. *P < 0.05 t-test vs. 3′UTR mutant; #P < 0.05 t-test vs. ICAM-1 3′UTR reporter construct.