Figure 7.

Dll4 and Kdr expression in mutant embryos. Embryos of the indicated genotypes were hybridized with riboprobes for Dll4 (A–C) and Kdr (D–F). Note the more severe dysmorphogenesis of the Notch1^−/− Notch4^−/− double mutant embryos (C,F) compared with the Notch1^−/− single mutant embryos (B,E). Dll4 expression was not downregulated in either the Notch1^−/− or Notch1^−/− Notch4^−/− mutant embryos. However, the expression patterns of both Dll4 and Kdr reveal disruptions in vascular morphogenesis in the mutant embryos.