Vascular endothelial growth factor (VEGF) is an important mediator of vascular development and postnatal angiogenesis.1,2 Homozygous deletion of VEGF gene leads to impaired vascular formation and early embryonic lethality.3 Interestingly, deletion of just one VEGF allele is sufficient to produce similar vascular abnormalities,3,4 suggesting that the strength and integrity of the VEGF signaling ...
