MAGP-2

MAGP-2 (Microfibril-associated glycoprotein 2), also called MFAP5 (microfibrillar associated protein 5) is a secreted, cell-associated 25 kDa mammalian member of the MFAP family of proteins. Both MAGP-1 and MAGP-2 bind and covalently crosslink Fibrillin-1 and -2 through the Cys-rich binding domain. Functionally, the MAGP-2 RGD motif binds to the integrin alpha v beta 3, allowing cell attachment to microfibrils. MAGP‑2 is thought to facilitate microfibril assembly and induce elastin fiber formation. Through its binding to EGF repeats, MAGP‑2 mediates the metalloproteinase-dependent release of Jagged1, and the metalloproteinase-independent release of Notch extracellular domains. In endothelial cells, MAGP-2 promotes angiogenic sprouting by inhibiting Notch signaling, by binding to integrin alpha v beta 3 (which then enhances VEGF signaling), and/or enhancing the endothelial cell response to FGF basic and EGF. In ovarian cancer, MAGP-2 expression is associated with cancer cell survival, increased microvessel density, and poor prognosis.