(A) Quantitative real-time PCR analysis of the mRNA expression levels of endothelial markers (VE-Cadherin, PECAM-1) and mesenchymal markers (α-SMA, VIMENTIN and FN1) in AdV-GFP and AdV-SOX7 infected HUVECs. Results were normalized to reference gene GAPDH. RNA levels in control (AdV-GFP) are set as 1. Data are shown as the mean ± SEM, two-tailed unpaired t test was used for statistical calculation for each marker, n=3 independent experiments, **P<0.01 vs AdV-GFP. (B) (Left), Representative immunoblots of VE-cadherin and SOX7 in HUVECs transfected with AdV-GFP and AdV-SOX7. GAPDH was used as internal control. (Right), The band density of VE-cadherin on the Western blot of five independent protein samples was digitally quantified by ImageJ software. Data shown are the mean ± SEM, two-tailed unpaired t test was used for statistical calculation, n=5 per group, ***P<0.001 vs AdV-GFP. (C) Immunofluorescence staining for Sox7 (red) and VE-cadherin (green) in E10.5 embryonic mouse hearts. White arrows denote that both SOX7 and VE-cadherin are expressed in ECs. The experiments were repeated at least three times independently. A, atrium; V, ventricle. Up panel, scale bars = 200 μm; lower panel, scale bars = 100 μm.