title: Human sperm binding is mediated by the sialyl-Lewis(x) oligosaccharide on the zona pellucida.
abstract: Human fertilization begins when spermatozoa bind to the extracellular matrix coating of the oocyte, known as the zona pellucida (ZP). One spermatozoan then penetrates this matrix and fuses with the egg cell, generating a zygote. Although carbohydrate sequences on the ZP have been implicated in sperm binding, the nature of the ligand was unknown. Here, ultrasensitive mass spectrometric analyses revealed that the sialyl-Lewis(x) sequence [NeuAcα2-3Galβ1-4(Fucα1-3)GlcNAc], a well-known selectin ligand, is the most abundant terminal sequence on the N- and O-glycans of human ZP. Sperm-ZP binding was largely inhibited by glycoconjugates terminated with sialyl-Lewis(x) sequences or by antibodies directed against this sequence. Thus, the sialyl-Lewis(x) sequence represents the major carbohydrate ligand for human sperm-egg binding.
authors.affiliation: Division of Molecular Biosciences, Faculty of Natural Sciences, Imperial College London, SW7 2AZ, UK.
authors.forename: Poh-Choo
authors.initials: PC
authors.lastname: Pang
authors.forename: Philip C N
authors.initials: PC
authors.lastname: Chiu
authors.forename: Cheuk-Lun
authors.initials: CL
authors.lastname: Lee
authors.forename: Lan-Yi
authors.initials: LY
authors.lastname: Chang
authors.forename: Maria
authors.initials: M
authors.lastname: Panico
authors.forename: Howard R
authors.initials: HR
authors.lastname: Morris
authors.forename: Stuart M
authors.initials: SM
authors.lastname: Haslam
authors.forename: Kay-Hooi
authors.initials: KH
authors.lastname: Khoo
authors.forename: Gary F
authors.initials: GF
authors.lastname: Clark
authors.forename: William S B
authors.initials: WS
authors.lastname: Yeung
authors.forename: Anne
authors.initials: A
authors.lastname: Dell
mesh_terms: D000906:Antibodies / Q000276:immunology; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D004527:Egg Proteins / Q000737:chemistry / Q000378:metabolism*; D005260:Female; D005643:Fucose / Q000737:chemistry; D006001:Glycoconjugates / Q000378:metabolism; D006801:Humans; D008024:Ligands; D008297:Male; D008562:Membrane Glycoproteins / Q000737:chemistry / Q000378:metabolism*; D009844:Oligosaccharides / Q000737:chemistry / Q000276:immunology / Q000378:metabolism*; D011956:Receptors, Cell Surface / Q000737:chemistry / Q000378:metabolism*; D019087:Selectins / Q000378:metabolism; D000080506:Sialyl Lewis X Antigen; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013084:Sperm-Ovum Interactions; D013094:Spermatozoa / Q000378:metabolism*; D015044:Zona Pellucida / Q000737:chemistry / Q000378:metabolism*; D000072216:Zona Pellucida Glycoproteins
chemical_list: D000906:Antibodies; D004527:Egg Proteins; D006001:Glycoconjugates; D008024:Ligands; D008562:Membrane Glycoproteins; D009844:Oligosaccharides; D011956:Receptors, Cell Surface; D019087:Selectins; D000080506:Sialyl Lewis X Antigen; D000072216:Zona Pellucida Glycoproteins; D005643:Fucose