Figure 6. Endothelial YAP/TAZ is required for vascular network formation in brain.

(A) Diagram for EC-specific deletion of Yap/Taz in brain vessels from P2 and their analyses at P12 in Yap/Taz^iΔEC mice. (B and C) Images of CD31⁺ vessels of cerebral cortex and striatum, and comparisons of indicated parameters in WT and Yap/Taz^iΔEC mice (n = 5, each group). The yellow dashed line demarcates the border between cortex and striatum. Scale bars: 500 μm. (D and E) Magnified images of tip ECs and comparisons of indicated parameters in WT and Yap/Taz^iΔEC mice (n = 5, each group). Tip ECs of Yap/Taz^iΔEC mice exhibit an aneurysm-like structure with less and dysmorphic filopodia (white arrowheads). Scale bars: 25 μm. (F and G) Images and comparisons of levels of glucose transporter 1 (GLUT1), transferrin receptor (TfR), PLVAP, and PDGFRβ⁺ pericyte coverage onto CD31⁺ vessels in cerebral striatum of WT and Yap/Taz^iΔEC mice (n = 5, each group). Scale bars: 50 μm. (H) Diagram for EC-specific deletion of Yap/Taz from P2 and sampling of brain ECs and their analyses at P8 in Yap/Taz^iΔEC mice. (I) GSEA of isolated brain ECs showing downregulation of YAP signature genes in Yap/Taz^iΔEC compared with those in WT mice, and correspondent heatmaps of the top 15 enriched genes. ES, enrichment score; NES, normalized enrichment score. Error bars represent mean ± SD. *P < 0.05 vs. WT by Mann-Whitney U test.