Methods of using testis-specific insulin homolog polypeptides

Abstract

The present invention provides testis-specific insulin homolog polypeptides and polynucleotides encoding the polypeptides, as well as related compositions and methods are disclosed. The polypeptides and polynucleotides may be used within methods for enhancing viability of cryopreserved sperm, for enhancing sperm motility, to enhance fertilization in methods of assisted reproduction, as contraceptives and other related uses.

1 . A method of enhancing sperm motility wherein a Zins2 testis-specific insulin homolog polypeptide selected from the group consisting of: 
 (a) polypeptides comprising a sequence of amino acids encoded by the nucleotide sequence as shown in SEQ ID NO: 1 or SEQ ID NO:12;    (b) allelic variants of (a); and    (c) Zins2 testis-specific insulin homolog polypeptides which are at least 85% identical to (a) or (b);    is added to sperm, an egg, an egg-sperm mixture, prior to fertilization.    
     
     
         2 . A method of enhancing sperm motility according to  claim 1  wherein said Zins2 testis-specific insulin homolog is added to sperm following cryopreservation.