Vascular Endothelial Growth Factor Receptor 3 (VEGFR3)

FLT4, is a tyrosine kinase receptor for vascular endothelial growth factors C and D. The protein is thought to be involved in lymphangiogenesis and maintenance of the lymphatic endothelium. Mutations in this gene cause hereditary lymphedema type IA.The FLT4 mRNA signals first became detectable in the angioblasts of head mesenchyme, the cardinal vein, and extraembryonally in the allantois of 8.5-day p.c. postcoitus embryos. In 12.5-day p.c. embryos, the FLT4 signal decorated developing venous and presumptive lymphatic endothelia, but arterial endothelia were negative. FLT4 mRNA became restricted to vascular plexuses devoid of red cells, representing developing lymphatic vessels. In adult human tissues, only the lymphatic endothelia and some high endothelial venules expressed FLT4 mRNA.