Proteolysis of the zona pellucida by acrosin: The nature of the hydrolysis products

Boar sperm acrosin was previously shown to hydrolyze the porcine zona pellucida in a specific and limited fashion. The action of acrosin on its presumed physiological substrate was investigated further in terms of the hydrolysis products formed. Peptide mapping experiments of zona pellucida glycoprotein families using acrosin demonstrated the formation of several products 2-4K smaller than the original susceptible families. When zona pellucida hydrolysates were examined with gel filtration, the hydrolysis products were associated in large macromolecular aggregates. These observations suggest that zona pellucida solubilization by acrosin may not be a relevant criterion for assessing acrosin's role in sperm penetration of the zona pellucida.