Abstract: The present invention provides compositions and methods for regulating fertility in mammals. In general, the invention relates to a novel protein produced by oocytes named JY-1, and nucleic acids encoding the JY-1 protein, for controlling folliculogenesis and early embryonic development, particularly in monoovulatory species. In particular, the present invention provides nucleic acid and amino acid sequences encoding JY-1, vectors for the expression of JY-1, host cells expressing JY-1, RNAi probes for reducing levels of JY-1 message, and antibodies to JY-1. Specifically, developing and mature oocytes express JY-1 in vivo, while granulosa cells treated in vitro with recombinant JY-1 (rJY-1) protein reduced cell proliferation while increasing progesterone synthesis and estradiol production. Further, reducing JY-1 protein in developing embryos in vitro using inhibitory siRNA constructs corresponded with arrested blastocyte maturation.

Abstract: A fusion protein formed of an antigenic inhibin peptide inserted into hepatitis B capsid protein is expressed from a chimeric gene forming an effective immunogen which induces anti-inhibin antibodies when administered to a host animal.