Fig. 2.

Activation of Sox17 at onset of EC regeneration and Sox17-mediated Cyclin E1 expression. a qPCR analysis of gene expression in sorted CD31⁺ cells from mTmG-Scl mice before and after injury (12 mg/kg i.p.). Sox17, Vegfr2, and Ccne1 increased significantly at day 2 post-LPS compared to baseline. n = 3. Color scale: the fold change increases from red to white to green color. b Western blot analysis in fresh isolated ECs from wild-type mice and quantification c showed a 5-fold increase in Sox17 protein expression within 1 day following injury compared to baseline and followed by recovery within 3 days post-LPS. n = 3. d, e Western blot analysis of cultured HLMVECs in which Sox17 was overexpressed showed 2.5x fold increase in Cyclin E1 protein expression relative to control cells. n = 3. OE, overexpression. f Representation of the CCNE1 promoter region with Sox17 binding sites (circled numbers) and their sequences. g HLMVECs were retrovirally transduced with Sox17 or control plasmid for 3 days, and Ch-IP assay followed by qPCR was performed to amplify Sox17 binding sites in the CCNE1 promoter. n = 3. h 293T cells were transfected with a Sox17 overexpression plasmid containing CCNE1 luciferase reporter constructs. Luciferase values were normalized to Renilla luciferase control reporter values. A schematic representation of corresponding deletion constructs is presented in the right panel. n = 3 and duplicates per sample. **P < 0.01 and ***P < 0.001. Data are shown as mean ± SEM. Analysis was performed using one-way ANOVA for (c) and two-way ANOVA with Bonferroni post-tests for (e, g, h)