Neuropilin-1 is required for endothelial cell adhesion to soluble vascular endothelial growth factor receptor 1.

Neuropilin-1 (NRP-1) is a semaphorin receptor involved in neuron guidance, and a co-receptor for selected isoforms of the vascular endothelial growth factor (VEGF) family. NRP-1 binding to several VEGF-A isoforms promotes growth factor interaction with VEGF receptor (VEGFR)-2, increasing receptor phosphorylation. Additionally, NRP-1 directly interacts with VEGFR-1, but this interaction competes with NRP-1 binding to VEGF-A165 and does not enhance VEGFR-1 activation.