Characterization of the postacrosomal sheath of bovine spermatozoa.
A purified head fraction was prepared from bovine epididymal spermatozoa and was utilized to identify the solubility characteristics and major polypeptide components of the postacrosomal sheath. Sperm heads extracted in nonionic-detergent-containing or high-salt-containing solutions retained an intact postacrosomal sheath, but it was readily solubilized by high pH extraction solutions. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed a major polypeptide of 58,000 daltons (58-kD) in the high pH extract solution. Antibodies to the 58-kD polypeptide specifically reacted with the postacrosomal segment by immunofluorescence and by electron microscopic immunohistochemistry were shown to bind the postacrosomal sheath. We conclude that this 58-kD polypeptide is a constituent of the postacrosomal sheath and that its distribution is restricted to the postacrosomal segment.
Olson
G E
GE
Department of Cell Biology, Vanderbilt University, Nashville, Tennessee 37232.
Winfrey
V P
VP
D000177:Acrosome / Q000032:analysis / Q000648:ultrastructure; D000818:Animals; D002417:Cattle / Q000502:physiology*; D002458:Cell Fractionation; D004591:Electrophoresis, Polyacrylamide Gel; D004797:Enzyme-Linked Immunosorbent Assay; D008297:Male; D008854:Microscopy, Electron; D013094:Spermatozoa / Q000032:analysis* / Q000648:ultrastructure