Role of protein kinase C in the acrosome reaction of mammalian spermatozoa.
Mammalian spermatozoa undergo a Ca(2+)-dependent exocytotic event before fertilization which is known as the acrosome reaction. The process of exocytosis in several cell systems is mediated by a protein kinase C (PKC)-catalysed phosphorylation. Addition of phorbol 12-myristate-13-acetate or the membrane-permeant diacylglycerol analogue 1-oleoyl-2-acetylglycerol, which are potent activators of PKC, to bovine spermatozoa resulted in stimulation of the acrosome reaction. This stimulation was inhibited by low concentrations (50% inhibition at 0.7 nM) of the PKC inhibitor staurosporine. PKC specific activity in bovine spermatozoa is extremely low in comparison with other cells; however, it is comparable with the activity found in human spermatozoa. Immunohistochemical analysis using anti-PKC antibodies revealed staining in the equatorial segment, the post-acrosomal region and the upper region of the head. We propose that PKC is involved in the mammalian sperm acrosome reaction.
Breitbart
H
H
Department of Life Sciences, Bar Ilan University, Ramat Gran, Israel.
Lax
J
J
Rotem
R
R
Naor
Z
Z
D000177:Acrosome / Q000187:drug effects / Q000201:enzymology* / Q000502:physiology; D000470:Alkaloids / Q000494:pharmacology; D000818:Animals; D002417:Cattle; D007150:Immunohistochemistry; D066298:In Vitro Techniques; D008297:Male; D011493:Protein Kinase C / Q000037:antagonists & inhibitors / Q000378:metabolism*; D013094:Spermatozoa / Q000201:enzymology*; D019311:Staurosporine; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
D000470:Alkaloids; D011493:Protein Kinase C; D019311:Staurosporine; D013755:Tetradecanoylphorbol Acetate