April 16, 2014

expert reaction to identification of receptor on mouse egg cells that allows sperm cells to attach and fertilise egg

A receptor on mouse egg cells that allows sperm cells to attach to and fertilize the eggs was identified by researchers publishing in Nature.

Dr Allan Pacey, Fertility Expert at the University of Sheffield, said:

“We are still remarkably sketchy about some of the key molecules involved in the early stages of fertilisation when the sperm and egg first interact. Yet the information could be immensely useful to help in the diagnosis of infertility but also in the design of new novel contraceptives for both humans and other animal species.

“The paper published in Nature by Gavin Wright and colleagues makes a major advance to our knowledge by identifying one of the unknown pieces in the molecular jigsaw of mammalian fertilisation. The identification of the egg-protein (called Juno), that the sperm protein Izumo1 first interacts with, is very exciting.

“Not only have the scientists shown that this protein is essential for fertilisation, it also seems to have a key role in preventing the egg being fertilised by more than one sperm, by being shed from the egg once the first sperm has fertilised. The identification of the Juno protein opens up many exciting prospects.

“Perhaps the most obvious biomedical application of this finding is whether screening for this protein (or its gene in a blood sample) could be used as a test of fertility. We know that fertilisation failure in IVF is quite rare, and so I suspect the lack or dysfunction of this protein is probably not a major cause of infertility in couples. However, it would be useful to know how many women have eggs that lack this protein so we can properly assess this.

“The second, and perhaps most likely application, is whether scientists could devise drugs or vaccines that could block the way this protein works or how the sperm protein Izumo1 interacts with it. This could lead to a new and novel non-hormonal contraceptive for both humans and other species of mammals.

“In summary, I think this is a very exciting paper and I would like to congratulate the authors on their work.”

‘Juno is the egg Izumo receptor and is essential for mammalian fertilization’ by Enrica Bianchi et al. published in Nature on Wednesday 16 April 2014.