title: Involvement of N-linked carbohydrate chains of pig zona pellucida in sperm-egg binding.
abstract: The sperm receptor activity of pig zona pellucida has been previously shown to exist in one of the components, pig zona protein 3 alpha (PZP3 alpha), that can be purified after the removal of sialylated and/or sulfated N-acetylpoly(lactosamine) by digestion with endo-beta-galactosidase. In this study, we examined whether N-linked or O-linked carbohydrate chains are involved in the sperm receptor activity of pig zona pellucida. The elimination of N-linked carbohydrate chains from endo-beta-galactosidase-digested PZP3 alpha by digestion with N-glycanase markedly reduced its inhibitory effect on sperm-egg binding in an in vitro competition assay, whereas the elimination of O-linked carbohydrate chains by alkali treatment hardly reduced the inhibitory effect. These results indicate that N-linked carbohydrate chains of PZP3 alpha play a major role in mediating the sperm binding of zona pellucida in pig.
authors.affiliation: Department of Chemistry, Faculty of Science, Chiba University, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Yonezawa
authors.forename: H
authors.initials: H
authors.lastname: Aoki
authors.forename: Y
authors.initials: Y
authors.lastname: Hatanaka
authors.forename: M
authors.initials: M
authors.lastname: Nakano
mesh_terms: D000581:Amidohydrolases; D000818:Animals; D001665:Binding Sites; D050260:Carbohydrate Metabolism; D002241:Carbohydrates / Q000737:chemistry / Q000302:isolation & purification; D004527:Egg Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D005260:Female; D006026:Glycoside Hydrolases; D066298:In Vitro Techniques; D008297:Male; D008562:Membrane Glycoproteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D015394:Molecular Structure; D043524:Peptide-N4-(N-acetyl-beta-glucosaminyl) Asparagine Amidase; D011956:Receptors, Cell Surface / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D013084:Sperm-Ovum Interactions / Q000502:physiology*; D013094:Spermatozoa / Q000378:metabolism; D013552:Swine; D015044:Zona Pellucida / Q000737:chemistry / Q000378:metabolism*; D001616:beta-Galactosidase
chemical_list: D002241:Carbohydrates; D004527:Egg Proteins; D008562:Membrane Glycoproteins; D011956:Receptors, Cell Surface; C035027:egg surface sperm receptor; D006026:Glycoside Hydrolases; C026093:keratan-sulfate endo-1,4-beta-galactosidase; D001616:beta-Galactosidase; D000581:Amidohydrolases; D043524:Peptide-N4-(N-acetyl-beta-glucosaminyl) Asparagine Amidase