To establish whether miR-636 modulates IL1R1, RANK, IKBKB, or FAM13A expression levels by binding to their 3′-UTRs, CF cells were co-transfected with a luciferase reporter vector containing the 3′-UTR region of WT mRNA (WT-IL1R1-3′UTR, WT-RANK-3′-UTR, WT-IKBKB-3′-UTR, and WT-FAM13A-3′-UTR) or with the 3′-UTR mutated region of each target except FAM13A (M-IL1R1-3′UTR, M-RANK-3′-UTR, and M-IKBKB-3′-UTR) and with the miR-636 mimic or mimic control. The gene discussed is IL1R1; the disease is cystic fibrosis.