Induces capillary permeability and angiogenesis through VEGF receptor (KDR/VEGFR-2) signaling. Induces DNA synthesis in human umbilical vein endothelial cells, and promotes mouse embryonic stem cell proliferation and differentiation. Homodimer; disulfide-linked. Interacts with high affinity with KDR/VEGFR-2, and with a lower affinity with neuropilin-1 (NRP1) and neuropilin-2 (NRP2). Expressed by the venom gland. Belongs to the PDGF/VEGF growth factor family. Snake venom VEGF subfamily.