Zonadhesin

Zonadhesin is a protein that in humans is encoded by the ZAN gene. It is a member of the DUF285 family and is known to play a crucial role in sperm-egg binding during the process of fertilization.

Function

Zonadhesin is a sperm-specific protein that has been shown to bind to the egg's extracellular matrix, the zona pellucida. This binding is thought to be an essential step in the process of sperm-egg fusion. The protein is located in the acrosomal region of the sperm, which is the part of the sperm that first comes into contact with the egg.

Structure

The ZAN gene encodes a protein that is approximately 2,400 amino acids in length. The protein contains multiple domains, including a MAM domain, which is thought to mediate protein-protein interactions, and several von Willebrand factor type D domains, which are thought to be involved in binding to the zona pellucida.

Clinical significance

Mutations in the ZAN gene have been associated with infertility in men. In particular, some studies have found that men with certain mutations in the ZAN gene have sperm that are unable to bind to the zona pellucida, which prevents the sperm from fertilizing the egg.

Research

Research into zonadhesin and its role in fertilization is ongoing. Understanding the precise mechanisms by which zonadhesin mediates sperm-egg binding could potentially lead to new treatments for infertility.

See also

• Zona pellucida
• Fertilization
• Infertility
• Protein
• Gene