- The major fat-globule membrane proteins, bovine components 15/16 and guinea-pig GP 55, are homologous to MGF-E8, a murine glycoprotein containing epidermal growth factor-like and factor V/VIII-like sequences. Mather, I.H., Banghart, L.R., Lane, W.S. Biochem. Mol. Biol. Int. (1993)