Figure 6.

Morphological differences and junctional organization in control and β -catenin −/− endothelial cells in culture. A represents β-catenin flox/flox del (control) endothelial cells, whereas B represents the same cells after infection with an adeno vector expressing Cre recombinase (β-catenin flox del/flox del, or −/−). In C, E, and G, endothelial cells cultured from control embryos are shown, whereas D, F, and H show endothelial cells from β-catenin −/− embryos. Although control endothelial cells exhibit classical cobblestone morphology (A and C), β-catenin −/− cells are more elongated and have a fibroblastoid/mesenchymal morphology (B and D). Phalloidin staining shows more elongated and thinner bundles of actin filaments in β-catenin −/− cells (F), as compared with controls (E). β-Catenin staining is undetectable at intercellular contacts of −/− cells (compare G and H), whereas ZO-1 (I and J) and VE-cadherin (K and L) are correctly organized at intercellular junctions.