invertebrate gonadotropin-releasing hormone receptors, member of the class A family of seven-transmembrane G protein-coupled receptors
GnRHR, also known as luteinizing hormone releasing hormone receptor (LHRHR), plays an central role in vertebrate reproductive function; its activation by binding to GnRH leads to the release of follicle stimulating hormone (FSH) and luteinizing hormone (LH) from the pituitary gland. GnRHR is expressed predominantly in the gonadotrope membrane of the anterior pituitary as well as found in nuemerous extrapituitary tissues including lymphocytes, breast, ovary, prostate, and cancer cell lines. There are at least two types of GnRH receptors, GnRHR1 and GnRHR2, which couple primarily to G proteins of the Gq/11 family. GnRHR is closely related to the adipokinetic hormone receptor (AKH), which binds to a lipid-mobilizing hormone that is involved in control of insect metabolism. They share a common ancestor and are members of the class A of the seven-transmembrane, G-protein coupled receptor (GPCR) superfamily.