Researchers from the Sanger Institute have recently identified two of the proteins involved in mammalian fertilization. The sperm protein, named Izumo after a marriage shrine from Japan, and the egg protein, named Juno after the Roman goddess of fertility, are two key components to having the egg and the sperm bind. Twenty percent of infertility cases have no known cause, and lack of these proteins might help to explain these mysteries. Researchers also theorize that Juno has a role in the formation of the fertilization envelope. Since we just studied this, I thought it was very interesting!

http://www.ncbi.nlm.nih.gov/pubmed/24739963