Probably plays a major role in determining the retinal structure as well as in the closure of the neural tube.; May regulate extracellular matrix-dependent motility and morphogenesis of endothelial and non-endothelial cells; the function requires homotrimerization and implicates MAPK signaling.; Potently inhibits endothelial cell proliferation and angiogenesis. May inhibit angiogenesis by binding to the heparan sulfate proteoglycans involved in growth factor signaling. Inhibits VEGFA-induced endothelial cell proliferation and migration. Seems to inhibit VEGFA-mediated signaling by blocking the interaction of VEGFA to its receptor KDR/VEGFR2. Modulates endothelial cell migration in an integrin-dependent manner implicating integrin ITGA5:ITGB1 and to a lesser extent ITGAV:ITGB3 and ITGAV:ITGB5. May negatively regulate the activity of homotrimeric non-collagenous domain 1.

> 90% as determined by SDS-PAGE.