A newly discovered function of a sperm protein may help diagnose and treat human fertility problems.
It may also lead to the development of more sophisticated forms of contraception, like the male birth control pill.
The sperm protein IZUMO1 binds sex cells and plays an essential role in fusing the cells to allow the exchange of genetic material, and ultimately, the creation of the zygote.
New research has found that once the binding has taken place, the sperm protein also acts as a fusogen, meaning it fuses the membranes of the sperm and egg cells by exchanging and combining their respective DNA into a single nucleus.
Its functions of binding and fusing were found to take place in different regions of the protein, meaning that they can potentially be isolated to address specific fertilization problems. This may open the door to more tailored and personalized fertility treatments and diagnosis.
The sperm protein’s new-found function may also open the door to new approaches to next-generation male oral contraceptives that temporarily disrupt the sperm protein’s binding and/or fusing abilities.
It is the first such protein to be designated as a fusogen in mammalian reproduction. The researchers discovered this by utilizing sperm and eggs from mice and kidney cells in culture.
The study was conducted by researchers at the Technion in Haifa, in collaboration with researchers at Nagoya and Tokyo Universities in Japan.
The protein IZUMO1 was first discovered in 2005 to be critical for the binding of sex cells. It was named after one of the most sacred shrines in Japan, the Izumo Ōyashiro, which is dedicated to marriage.
The research was published in The Journal of Cell Biology.