Promotes adhesion of endothelial cells through interaction with the alpha-v/beta-3 integrin receptor. Inhibits formation of vascular-like structures. May be involved in regulation of vascular morphogenesis of remodeling in embryonic development. Expressed in angioblasts and early endothelial cells. By embryonic day 13.5, also expressed in a restricted group of non-endothelial cells including chondrocytes and retinal neurons. Expressed in the embryo from day 7. After day 15.5, expression decreases and disappears completely by the time of birth. EGF2 and EGF3 form a rigid rod via an interdomain calcium ion binding site, while the long linker between EGF1 and EGF2 lends considerable flexibility to EGF1.