Fig. 5

tiRNA-Val targets sirt1 3′UTR leading to the accumulation of Hif-1α. a Sequence alignment of tiRNA-Val with the 3′UTRs of Sirt1. The seed region of tiRNA-Val is indicated in bold. b Luciferase assay indicated the mutation of the predicted tiRNA-Val binding site in Sirt1 3′UTR,and it abrogated the repressive effect of tiRNA-Val on the activity of Sirt1 3′UTR. Data are represented as the mean ± SD, n = 4, ^∗∗∗p < 0.001 vs. Sirt1 3′UTR^WT group. Statistical significance was assessed by two-tailed Student's t-test. c Luciferase assay indicated the mutation of the tiRNA-Val seed region, and it abrogated the repressive effect of tiRNA-Val on the activity of Sirt1 3′UTR. Data are represented as the mean ± SD, n = 4, ^∗∗∗p < 0.001 vs. pSIF + tiRNA-Val group. Statistical significance was assessed by two-tailed Student's t-test. d, e Western blotting analysis of Hif-1α and Sirt1 expression in HRMECs transfected with tiRNA-Val mimics and the scramble sequence RNA. Data are represented as the mean ± SD, n = 3, ^∗∗∗p < 0.001 vs. Control group. Statistical significance was assessed by two-tailed Student's t-test. f, g Western blotting analysis of Hif-1α and Sirt1 expression in the entire retina of normal and DR mice. Data are represented as the mean ± SD, n = 3, ^∗∗∗p < 0.001 vs. Control group. Statistical significance was assessed by two-tailed Student's t-test. WT: wile type; DR: diabetic retinopathy; Mut: mutation; OE: overexpression