Fig. 2.

Identification of PARP1 as a target gene of miR-7-5p. a The binding site of miR-7-5p in the 3′ UTR of PARP1 was predicted by bioinformatic analyses. b Luciferase reporter constructs containing the wild-type or mutated (one point mutation) 3′ UTR of PARP1 were designed according to miR-7-5p seed sequences. c Dual-luciferase reporter assay. Luciferase reporter constructs and miR-7-5p mimic/inhibitor were cotransfected into HEK293 cells, and luciferase activity was detected 48 h after transfection using nontransfected cells as control. d The level of PARP1 protein in SCLC cells was determined by Western blot using GAPDH as a loading control. e-f The expression of PARP1 protein in SCLC cells with alterations in miR-7-5p levels was detected by Western blotting. Cells were transfected with miR-7-5p mimic or inhibitor, and PARP1 protein was examined by Western blot. The mean ± SD of three independent experiments (upper panel) and representative images (lower panel) are shown for each condition (d-f). *P < 0.05, **P < 0.01 and ***P < 0.001