Protein Domain : Chemerin-like receptor 2 IPR002275

Type	Family
Description	G protein-coupled receptors (GPCRs) constitute a vast protein family that encompasses a wide range of functions, including various autocrine, paracrine and endocrine processes. They show considerable diversity at the sequence level, on the basis of which they can be separated into distinct groups [ ]. The term clan can be used to describe the GPCRs, as they embrace a group of families for which there are indications of evolutionary relationship, but between which there is no statistically significant similarity in sequence []. The currently known clan members include rhodopsin-like GPCRs (Class A, GPCRA), secretin-like GPCRs (Class B, GPCRB), metabotropic glutamate receptor family (Class C, GPCRC), fungal mating pheromone receptors (Class D, GPCRD), cAMP receptors (Class E, GPCRE) and frizzled/smoothened (Class F, GPCRF) [, , , , ]. GPCRs are major drug targets, and are consequently the subject of considerable research interest. It has been reported that the repertoire of GPCRs for endogenous ligands consists of approximately 400 receptors in humans and mice []. Most GPCRs are identified on the basis of their DNA sequences, rather than the ligand they bind, those that are unmatched to known natural ligands are designated by as orphan GPCRs, or unclassified GPCRs [].The rhodopsin-like GPCRs (GPCRA) represent a widespread protein family that includes hormone, neurotransmitter and light receptors, all of which transduce extracellular signals through interaction with guanine nucleotide-binding (G) proteins. Although their activating ligands vary widely in structure and character, the amino acid sequences of the receptors are very similar and are believed to adopt a common structural framework comprising 7 transmembrane (TM) helices [ , , ].Chemerin-like receptor 2 (CML2, also known as GPCR1), is a receptor for chemoattractant adipokine chemerin/RARRES2 that may have a role for in the regulation of inflammation and energy homeostasis [ , ]. This protein also acts also as a receptor for TAFA1, mediates its effects on neuronal stem-cell proliferation and differentiation via the activation of ROCK/ERK and ROCK/STAT3 signaling pathway []. In humans, GPR1 is expressed in the human hippocampus []. By contrast, the rat GPR1 gene is not expressed in hippocampus, demonstrating a functional variation for this receptor in these species [ ].
Short Name	CML2