Protein structure of vascular endothelial growth factor receptor (VEGF) and placental growth factor receptor (PIGF) Flt-1 and sFlt-1 are illustrated. Flt-1 has 7 immunoglobulin domains (lgG), which are thought to mediate ligand binding to VEGF and PIGF. sFlt-1 protein has a unique 31 AA C-terminus region derived from alternative splicing and lacks the transmembrane and cytoplasmic domains.
