Protein that gets sperm into egg identified

Chemical signals sent between mammalian sperm's Izumo1 protein and the egg protein Juno or Folr4 ensure that the reproductive cells fuse.

Genome Research Limited

Exactly what molecule in a mammal’s egg cell talks to sperm to let them wriggle inside has been difficult to identify. 

In 2005, scientists discovered that sperm carry a protein called Izumo1 that gets them to fuse with an egg. Now, research on mice shows that it’s the protein folate receptor 4, or Folr4, on the egg that plays the partner role to bring the reproductive cells together. The discovery, published April 16 in Nature, could lead to better contraceptives and fertility treatments. The team also suggests renaming the protein Juno after the Roman goddess of fertility and marriage. 

Ashley Yeager is the associate news editor at Science News. She has worked at The Scientist, the Simons Foundation, Duke University and the W.M. Keck Observatory, and was the web producer for Science News from 2013 to 2015. She has a bachelor’s degree in journalism from the University of Tennessee, Knoxville, and a master’s degree in science writing from MIT.

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