The Golgi complex form catalyzes the production of lactose in the lactating mammary gland and could also be responsible for the synthesis of complex-type N-linked oligosaccharides in many glycoproteins as well as the carbohydrate moieties of glycolipids. The cell surface form functions as a recognition molecule during a variety of cell to cell and cell to matrix interactions, as those occurring during development and egg fertilization, by binding to specific oligosaccharide ligands on opposing cells or in the extracellular matrix.Masri K.A., Biochem. Biophys. Res. Commun. 157:657-663(1988).Watzele G., Nucleic Acids Res. 18:7174-7174(1990).Mengle-Gaw L., Biochem. Biophys. Res. Commun. 176:1269-1276(1991).