Mori E, Mori T, Takasaki S
Department of Biochemistry, University of Tokyo, Japan.
Biochem Biophys Res Commun. 1997 Sep 8;238(1):95-9. doi: 10.1006/bbrc.1997.7249.
Mouse eggs fixed with paraformaldehyde were incubated with various exoglycosidases and their sperm-binding activities were examined. The number of sperm bound per egg was increased by sialidase treatment and decreased by beta-galactosidase treatment. No prominent reduction of sperm-binding was observed after alpha-galactosidase treatment. Mouse sperm also bound to asialofetuin-coupled agarose beads but not to fetuin-coupled beads. The sperm-binding was abolished when asialofetuin-gel was treated with beta-galactosidase specific to the beta 1-->4 linkage or N-Glycanase. Furthermore asialofetuin, but not beta-galactosidase-treated asialofetuin, competitively inhibited the binding of sperm to the zona pellucida of live eggs. These results suggest that mouse sperm recognize beta-galactose residues of the zona pellucida at the initial stage of the binding.
