In the United States, nearly 2.6 million couples have been treated for infertility with about 40 percent of those cases thought to be due to male infertility. Now, a study published in the August 22 issue of Cell identifies a new protein that is required for a sperm to bind to an egg during the process of fertilization. This research provides important new insight into the molecular mechanisms that are involved in the initial events of sperm-egg association and may shed light on what underlies some instances of male infertility.
There are a variety of factors that can lead to male infertility, including defects in sperm motility and insufficient sperm production. However, in many cases, the sperm of infertile men appear to be completely normal. Barry D. Shur, PhD, professor and chair of cell biology at Emory University School of Medicine, and postdoctoral fellow Michael A. Ensslin, PhD, took a close look at the specific molecules and events required for a sperm to recognize an egg so that fertilization can take place. The researchers identified a protein on the surface of mouse sperm that is required for the sperm to successfully bind to the outside of the egg. The protein, called SED1, binds specifically to unfertilized eggs and no longer recognizes an egg after it has been fertilized. When examined in the laboratory, sperm without SED1 were unable to bind to an egg. Further, mice without SED1 had greatly reduced fertility even though the sperm appeared normal in number and motility.
These results strongly suggest that SED1 plays a critical role in the initial association between sperm and egg. "An understanding of the molecular mechanisms underlying sperm-egg binding may give insight into the basis for at least some percentage of male infertility," explains Dr. Shur. "In addition, this work is of interest because the composition of SED1 is similar to other types of cell-cell binding proteins, which have not previously been implicated in sperm-egg binding."
Holly Korschun | EurekAlert!
MicroRNA helps cancer evade immune system
19.09.2017 | Salk Institute
Ruby: Jacobs University scientists are collaborating in the development of a new type of chocolate
18.09.2017 | Jacobs University Bremen gGmbH
Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!
When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...
For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.
Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...
MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems Holding GmbH about commercial use of a multi-well tissue plate for automated and reliable tissue engineering & drug testing.
MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems...
Pathogenic bacteria are becoming resistant to common antibiotics to an ever increasing degree. One of the most difficult germs is Pseudomonas aeruginosa, a...
Scientists from the MPI for Chemical Energy Conversion report in the first issue of the new journal JOULE.
Cell Press has just released the first issue of Joule, a new journal dedicated to sustainable energy research. In this issue James Birrell, Olaf Rüdiger,...
19.09.2017 | Event News
12.09.2017 | Event News
06.09.2017 | Event News
19.09.2017 | Event News
19.09.2017 | Physics and Astronomy
19.09.2017 | Power and Electrical Engineering