Glycosylation of G-protein-coupled receptors for hormones central to normal reproductive functioning: Its occurrence and role

Many hormones that are central to normal reproductive functioning mediate their physiological effects by activating a receptor which belongs to the large family of G-protein-coupled receptors (GPCR). Members of this family of receptor proteins are usually glycosylated on extracellular domains. In recent years the role of this glycosylation in cell surface expression/protein folding, ligand recognition and receptor-effector coupling has been investigated. This review summarises current knowledge of the role of glycosylation in the functioning of the receptors for gonadotrophin-releasing hormone (GnRH), luteinizing hormone/human chorionic gonadotrophin (LH/HCG), follicle stimulating hormone (FSH), oxytocin (OT) and vasopressin (AVP).