Fig. 4

DNMT3B is the Main Enzyme Affecting the Abnormal Methylation of the PLTP Promoter. A Expression of enzymes involved in DNA methylation in HRMECs (NC vs HG, n = 8). B Expression of enzymes involved in DNA methylation in retina (NC vs DR mice, n = 3). C Western blot analysis of DNMT1 and DNMT3B in HRMECs (NC vs HG, n = 3) or retina (NC vs DR mice, n = 3). D Quantitative analysis of promoter methylation levels of PLTP in HRMECs (siNC, siDNMT1 and siDNMT3B, n = 3). E PCR analysis of PLTP in HRMECs (siNC, siDNMT1 and siDNMT3B, n = 3). F Western blot analysis of PLTP in HRMECs (siNC, siDNMT1 and siDNMT3B, n = 3). G Luciferase reporter assay for DNMT3B interaction with the PLTP promoter (n = 3). Migration assay of HRMECs H and quantitative analysis I (HG vs HG + siDNMT3B, n = 5). Tube formation assay of HRMECs J, and quantitative analysis of nodes and branches length (K) (HG vs HG + siDNMT3B, n = 3). NC, normal control; HG, high glucose; DR, diabetic retinopathy; FLuc, firefly luciferase; Rluc, renilla luciferase. *p < 0.05, **p < 0.01, ***p < 0.001