Fig. 4

DIXDC1 regulates VEGFR2 level in vitro and in vivo. A VEGFR2 protein expression level was reduced when DIXDC1 was suppressed in EC by using DIXDC1 siRNA (60 nM). B Significantly increased VEGFR2 protein expression was observed when DIXDC1 was overexpressed in EC. C, D Relative mRNA level of VEGFR2 and DIXDC1. E Whole-mount staining of E10.5 WT and DIXDC1 KO embryos with CD31 and VEGFR2, demonstrating overall decrease in VEGFR2. n = 5 per group. Scale bars 500 μm. F Quantification of E (percentage of control). G Whole-mount staining of retinae of P8.5 retinae from WT and DIXDC1-KO pups showing decreased VEGFR2 expression. n = 6 per group. Scale bars 500 μm. H Quantification of G (percentage of control). I MLEC from WT and Dixdc1 KO mice at p9.5 displaying reduced VEGFR2 level leading to decreased downstream VEGFR2 signaling. J, K, and L Quantification of relative intensity of p-VEGFR2, p-AKT, and p-ERK1/2 of MLEC western blot. All experiments were repeated at least 5 different sets of ECs treated with siRNA or DIXDC1 siRNA. All experiments were repeated at least 3 different sets of WT and DIXDC1-KO littermates. *p < 0.05, **p < 0.005, and ***p < 0.0001, by paired, 2-tailed Student’s t test and one-way ANOVA. Error bars represent the mean ± SD. Individual values can be found in Additional file 6: Fig 4