Vascular Endothelial Growth Factor Receptors

Vascular endothelial growth factor receptors (VEGFRs) are a set of three homologous transmembrane receptor tyrosine kinases that bind vascular endothelial growth factors (VEGFs). VEGFRs are expressed throughout the vascular and lymphatic systems and by some cells of the immune and nervous systems. Dimeric VEGF binding to the VEGFR extracellular domains promotes receptor dimerization and mutual receptor subunit tyrosine transphosphorylation of the intracellular domains. Specific proteins bind these receptor phosphotyrosine residues initiating a signaling cascade that culminates in cellular migration, mitosis, and survival promoting the growth of blood and lymphatic vessels, respectively, termed ‘angiogenesis’ and ‘lymphangiogenesis’. Alternative splicing generates soluble VEGFRs that can sequester VEGF ligands and inhibit VEGFR activation.