title: Ultrastructural mapping of a sperm plasma membrane autoantigen before and after the acrosome reaction.
abstract: The rabbit sperm plasma membrane autoantigen, RSA, is a zona binding protein that binds the spermatozoon to the zona pellucida both before and after the acrosome reaction. In the present study rabbit spermatozoa undergoing the acrosome reaction in vitro are described and monospecific polyclonal mouse anti-RSA and protein A-gold label is used with the label-fracture technique (Pinto de Silva and Kan, J Cell Biol, 99:1156-1161, 1984) to map the location of RSA at the ultrastructural level before and after the acrosome reaction. RSA is most concentrated in the plasma membrane over the postacrosomal-equatorial region border. The label appears to cluster over the anterior aspects of the postacrosomal region's tooth-like projections. Following the acrosome reaction, RSA is still present in the postacrosomal region and often appears clustered in the medial aspects of the equatorial region.
authors.affiliation: Department of Cell Biology and Anatomy, University of North Carolina, Chapel Hill 27599.
authors.forename: N
authors.initials: N
authors.lastname: Esaguy
authors.forename: J E
authors.initials: JE
authors.lastname: Welch
authors.forename: M G
authors.initials: MG
authors.lastname: O'Rand
mesh_terms: D000177:Acrosome / Q000276:immunology / Q000502:physiology*; D000818:Animals; D001324:Autoantigens / Q000032:analysis*; D002462:Cell Membrane / Q000276:immunology; D005260:Female; D005455:Fluorescent Antibody Technique; D005614:Freeze Fracturing; D007150:Immunohistochemistry; D008297:Male; D008854:Microscopy, Electron; D011817:Rabbits; D013075:Sperm Capacitation; D013084:Sperm-Ovum Interactions; D013094:Spermatozoa / Q000276:immunology* / Q000502:physiology* / Q000648:ultrastructure; D015044:Zona Pellucida / Q000276:immunology
chemical_list: D001324:Autoantigens; C032872:rabbit sperm membrane autoantigen