Vascular Endothelial Growth Factor Receptor 1 (VEGFR1)

Vascular endothelial growth factor receptor-1 was originally discovered through the screening of a human placental cDNA library . It is a receptor tyrosine kinase (RTK) specific for the angiogenic factors VEGF (VEGF-A), PlGF, and VEGF-B. VEGF R1 is expressed in two forms via alternate splicing at the pre-mRNA level: a full-length, membrane bound receptor capable of transducing signal, and a truncated, soluble receptor (sVEGF R1) capable of sequestering ligand or dimerizing with full-length receptor and preventing signal transduction.

Although VEGF R1 null mutations are lethal, deletions of the kinase domain are not, suggesting that the soluble form, or at least the extracellular domain, is all that is necessary for normal vascular development.