Fig. 2

TFF1 targets miR-423-5p in ARPE-19 cells. a The relative levels of TFF1 were measured by qRT-PCR in the normal group and DR group showed that miR-423-5p was downregulated in DR group. b The predicted binding sites of miR-423-5p in the TFF1 3′-UTR. c The luciferase reporter vector containing TFF1-WT or TFF1-MUT was co-transfected with NC mimics, miR-423-5p mimics, NC inhibitor or miR-423-5p inhibitor. The relative luciferase activity is the ratio of the luciferase activity in each test cell sample to that in the control cell sample. The signal intensity of luciferase was lowest in TFF1-WT cells transfected with miR-185-3p mimics, and the miR-423-5p inhibitor significantly enhanced the luciferase activity. For d and e, ARPE-19 and RPE-J cells were transfected with NC mimics, miR-423-5p mimics, NC inhibitor or miR-423-5p inhibitor. The relative mRNA (d) and protein (e) levels of TFF1 were measured by qRT-PCR and Western blot, respectively. The data revealed that transfection of the miR-423-5p mimics significantly reduced expression of TFF1, while transfection of the miR-423-5p inhibitor increased the TFF1 expression. Data are presented as mean ± SD. Three replicate wells were used per sample in each experiment and experiments were replicated three times. * P < 0.05; ** P < 0.01