Scientists may have discovered the key to mammalian fertilization: the interaction between two proteins, Izumo and Juno, located on the surface of sperm and eggs, respectively. But until now, scientists didnt know what Izumo recognized, or to what it might bind. So researchers at the Wellcome Trust Sanger Institute in the UK created an artificial version of Izumo that they introduced to the surface of mouse eggs. This experiment allowed the scientists to identify Izumos binding partner on the eggs surface — a partner they named Juno, after the Roman goddess of fertility.