GPR49/LGR5 (G protein-coupled receptor 49/leucine-rich repeat-containing G protein-coupled receptor 5) is also known by the names FEX, GPR67, GRP49, HG38, and MGC117008). It is an orphan receptor and structurally related to members of the mammalian large transmembrane glycoprotein hormone receptor family (FSH-R, TSH-R, and LH-R). Within the LGR family here are three major subgroups: glycoprotein hormone receptors, a subgroup of GPR48, GPR49, and LGR6, and the receptors of relaxin family ligands (LGR7 and LGR8). LGR5 and GPR48/LGR4 were first identified and characterized in Hsu’s lab (1). Within its subgroup family, GPR49 is emerging as a significant player in stem cell biology as it is highly expressed on stem cells found in the small intestine, colon, and hair follicle.
Deficiency of GPR49 in mice has been shown to cause neonatal lethality characterized by the craniofacial ankyloglossia phenotype and gastrointestinal distension. LGR5 is a downstream target gene of Wnt signaling pathway (critical for morphogenesis and tumorigenesis) and it has also been reported as a receptor for R-spondins which are potent mediators of Wnt/beta-catenin as well as Wnt/PCP signaling. Yamamoto’s lab was able to correlate GPR49/LGR5 overexpression with beta-catenin mutations in hepatoceullular carcinomas (2). Accordingly, when compared to normal tissues, LGR5 is found upregulated in certain cancers such as colon and ovarian, where concommitant inhibition of LGR5 causes apoptosis (3).
Novus Biologicals offers various GPR49/LGR5 reagents for your research needs including: