Figure 3. circ_CELF1 binds miR-491-5p in NSCLC cells. (A) AGO2 RIP experiments were performed using an antibody against Ago2 on extracts from A549 cells. n = 3, *P < 0.05. (B) A schematic drawing showing the putative binding sites of miR-491-5p, miR-6763-5p, and miR-3150a-3p with respect to circ_CELF1. (C) The luciferase activity of WT- circ_CELF1 or mutant circ_CELF1 in HEK293 cells after co-transfection with miR-491-5p, miR-6763-5p, and miR-3150a-3p. n = 3, *P < 0.05. (D) A549 and H1975 cells were transfected with miR-491-5p or miR-NC for 48 h. The association between circ_CELF1 and miR-491-5p was assessed by FISH assay. (E) The expression of circ_CELF1 was detected by qRT-PCR under transfection of miR-491-5p mimic and si-miR-491-5p. n = 4, *P < 0.05. (F–G) The expression of miR-491-5p was explored by upregulation or downregulation of circ_CELF1. n = 4, *P < 0.05.