Sperm surface membrane protein that may be involved in sperm-egg plasma membrane adhesion and fusion during fertilization. It could be a potential receptor for the egg oligosaccharide residue N-acetylglucosamine, which is present in the extracellular matrix over the egg plasma membrane. The processed form has no detectable bacteriolytic activity in vitro (By similarity).
Subcellular locations: Cytoplasmic vesicle, Secretory vesicle, Acrosome membrane
Anterior acrosome in non-capacitated spermatozoa and retained in the equatorial segment and in the luminal face of both the inner and outer acrosomal membranes following capacitation and the acrosome reaction.