VEGFR-1 Protein, Rat (HEK293, His)

VEGFR-1 protein, a tyrosine-protein kinase, serves as a cell-surface receptor for VEGFA, VEGFB, and PGF, playing a crucial role in embryonic vasculature development, angiogenesis regulation, cell survival, migration, macrophage function, chemotaxis, and cancer cell invasion. It acts as a positive regulator of postnatal retinal hyaloid vessel regression and may function as a negative regulator of embryonic angiogenesis by inhibiting excessive proliferation of endothelial cells. In adulthood, VEGFR-1 can promote endothelial cell proliferation, survival, and angiogenesis, with its function in cell proliferation being cell-type specific. It facilitates PGF-mediated proliferation of endothelial cells and certain cancer cell types but does not promote proliferation of normal fibroblasts. With a high affinity for VEGFA and relatively low protein kinase activity, VEGFR-1 may function as a negative regulator of VEGFA signaling by limiting free VEGFA and preventing its binding to KDR. It modulates KDR signaling by forming heterodimers with KDR. Ligand binding activates multiple signaling cascades, including PLCG-mediated diacylglycerol and inositol 1,4,5-trisphosphate production, protein kinase C activation, phosphorylation of PIK3R1, leading to phosphatidylinositol 3-kinase activation, and subsequent downstream signaling pathways. VEGFR-1 also mediates the activation of MAP kinase and AKT1 signaling pathways, phosphorylates SRC, YES1, PLCG, and potentially CBL, and promotes phosphorylation of AKT1 and PTK2/FAK1, highlighting its diverse and integral role in regulating complex cellular processes.