Isolation of an arbacia sperm fertilization antigen.
Antisperm antibody fragments (IFab) block sea urchin fertilization by inhibiting the acrosome reaction and consequently sperm-egg attachment. We describe here a 68,000 dalton MW glycoprotein which neutralizes the fertilization-inhibiting action of IFab. This glycoprotein is a minor component is SDS-polyacrylamide gels of sperm membranes, but is greatly enriched in lithium diiodosalicylate extracts of the membranes. Final purification of the antigen was accomplished by elution from preparative SDS-polyacrylamide gels. This glycoprotein is evidently the sea urchin sperm receptor which interacts wih the egg jelly coat and acts as a "trigger" for the acrosome reaction.
D000818:Animals; D000941:Antigens / Q000302:isolation & purification*; D002462:Cell Membrane / Q000648:ultrastructure; D005306:Fertilization; D007140:Immunoglobulin Fab Fragments / Q000276:immunology*; D008297:Male; D008854:Microscopy, Electron; D008970:Molecular Weight; D012617:Sea Urchins; D013094:Spermatozoa / Q000276:immunology* / Q000648:ultrastructure
D000941:Antigens; D007140:Immunoglobulin Fab Fragments