Functional interactions between sulphated polysaccharides and proacrosin: implications in sperm binding and digestion of zona pellucida.
Acrosin is a serine protease located within mammalian acrosome as inactive proacrosin. Sulphated polymers bind to proacrosin and acrosin, to a domain different from the active site. Upon binding, these polymers induce proacrosin activation and some of them, such as fucoidan, inhibit sperm binding to the zona pellucida. In this work we have studied the interaction of solubilised zona pellucida glycoproteins (ZPGs), heparin and ARIS (Acrosome Reaction Inducing Substance of Starfish) with boar and human acrosin. We have found that ARIS, solubilised ZPGs and fucoidan, but not heparin, inhibit the binding of the monoclonal antibody against human acrosin C5F10 to boar or human proacrosin. These results suggest that fucoidan, solubilised ZPGs and ARIS bind to a related domain on the proacrosin surface. Moreover, ARIS was able to induce human proacrosin activation. On the other hand, neither ARIS nor heparin from porcine intestinal mucosa or bovine lung induced hamster sperm acrosome reaction or sperm motility. Recent data showed that acrosin is involved in dispersal of the acrosomal matrix after acrosome reaction. Thus, the control of the ZPG glycan chains over proacrosin activation may regulate both sperm penetration rate and limited proteolysis of zona pellucida proteins.
Pontifical Catholic University of Chile, Chile.
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Moreno
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Hoshi
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Barros
D000176:Acrosin / Q000187:drug effects / Q000378:metabolism*; D020101:Acrosome Reaction / Q000187:drug effects; D000818:Animals; D001665:Binding Sites; D002417:Cattle; D006224:Cricetinae; D004527:Egg Proteins / Q000378:metabolism; D004792:Enzyme Precursors / Q000187:drug effects / Q000378:metabolism*; D006023:Glycoproteins / Q000378:metabolism / Q000494:pharmacology; D006493:Heparin / Q000378:metabolism / Q000494:pharmacology; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins; D007413:Intestinal Mucosa / Q000737:chemistry; D008168:Lung / Q000737:chemistry; D008297:Male; D008562:Membrane Glycoproteins / Q000378:metabolism; D011134:Polysaccharides / Q000378:metabolism*; D011956:Receptors, Cell Surface; D013081:Sperm Motility / Q000187:drug effects; D013094:Spermatozoa / Q000378:metabolism*; D013431:Sulfates / Q000737:chemistry; D013552:Swine; D014360:Trypsin Inhibitor, Kunitz Soybean / Q000378:metabolism / Q000494:pharmacology; D015044:Zona Pellucida / Q000378:metabolism*; D000072216:Zona Pellucida Glycoproteins
C067898:ARIS protein, Asterias amurensis; D004527:Egg Proteins; D004792:Enzyme Precursors; D006023:Glycoproteins; D036341:Intercellular Signaling Peptides and Proteins; D008562:Membrane Glycoproteins; D011134:Polysaccharides; D011956:Receptors, Cell Surface; D013431:Sulfates; D000072216:Zona Pellucida Glycoproteins; D006493:Heparin; C007789:fucoidan; D014360:Trypsin Inhibitor, Kunitz Soybean; C022438:proacrosin; D000176:Acrosin