LPA6 (P2Y5) was cloned as an orphan GPCR and is closely related to the fourth lysophosphatidic acid receptor, LPA43. GPCRs share a similar topology, with seven transmembrane helices (TMHs) connected by three extracellular loops (ECLs), and three intracellular loops (ICLs); the N terminus is on the extracellular side of the membrane, and the C terminus is on the cytoplasmic side.LPA6 mRNA is expressed ubiquitously including in skin and hair follicle cells.n A recent study suggested that LPA6 is essential for human hair growth. A loss of function is not compensated for, and ultimately leads to pathological changes and hair loss
