CRISP polypeptides as contraceptives and inhibitors of sperm capacitation
Included in the present invention are methods of inhibiting sperm capacitation, inhibiting the phosphorylation of a protein at tyrosine residues, inhibiting an acrosomal reaction, and inhibiting fertilization of an egg by sperm with the administration of a CRISP polypeptide.
1. A method of inhibiting sperm capacitation comprising contacting sperm that have not undergone capacitation with a cysteine-rich secretory protein (CRISP) polypeptide under capacitation conditions, wherein the CRISP polypeptide has at least 95% sequence identity to human CRISP-1 (SEQ ID NO: 1) and the CRISP polypeptide inhibits tyrosine phosphorviation of sperm proteins.
2. A method of inhibiting sperm capacitation comprising contacting sperm that have not undergone capacitation with a cysteine-rich secretory protein (CRISP) polypeptide under capacitating conditions, wherein the CRISP polypeptide is human CRISP-1 (SEQ ID NO:1).
3. A method of inhibiting sperm capacitation comprising contacting sperm with the human CRISP-1 polypeptide SEQ ID NO: 1.