Rhodopsin-like receptors are a

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

protein Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, respon ...

s that comprise the largest group of

G protein-coupled receptor G protein-coupled receptors (GPCRs), also known as seven-(pass)-transmembrane domain receptors, 7TM receptors, heptahelical receptors, serpentine receptors, and G protein-linked receptors (GPLR), form a large group of evolutionarily-related p ...

Scope

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. GPCRs are usually described as "superfamily" because they embrace a group of

families Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

for which there are indications of evolutionary relationship, but between which there is no statistically significant similarity in sequence. The currently known superfamily members include the rhodopsin-like GPCRs (this family), the

secretin-like GPCR Secretin family receptor proteins, also known as Family B or family 2 of G-protein coupled receptors are regulated by peptide hormones from the glucagon hormone family. The family is different from adhesion G protein-coupled receptors. The secr ...

s, the cAMP receptors, the

fungal mating pheromone receptors Fungal pheromone mating factor receptors form a distinct family of G-protein-coupled receptors G protein-coupled receptors (GPCRs), also known as seven-(pass)-transmembrane domain receptors, 7TM receptors, heptahelical receptors, serpentine ...

, and the

metabotropic glutamate receptor The metabotropic glutamate receptors, or mGluRs, are a type of glutamate receptor that are active through an indirect metabotropic process. They are members of the group C family of G-protein-coupled receptors, or GPCRs. Like all glutamate re ...

family. There is a specialised database for GPCRs.

Function

The rhodopsin-like GPCRs themselves represent a widespread protein family that includes hormone, neuropeptide, 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.

Classes

Rhodopsin-like GPCRs have been classified into the following 19 subgroups (A1-A19) based on a phylogenetic analysis.

Subfamily A1

Chemokine receptor Chemokine receptors are cytokine receptors found on the surface of certain cells that interact with a type of cytokine called a chemokine. There have been 20 distinct chemokine receptors discovered in humans. Each has a rhodopsin-like 7- tr ...

** Chemokine (C-C motif) receptor 1 (, CKR1) ** Chemokine (C-C motif) receptor 2 (, CKR2) ** Chemokine (C-C motif) receptor 3 (, CKR3) ** Chemokine (C-C motif) receptor 4 (, CKR4) ** Chemokine (C-C motif) receptor 5 (, CKR5) ** Chemokine (C-C motif) receptor 8 (, CKR8) ** Chemokine (C-C motif) receptor-like 2 (, CKRX) * chemokine (C motif) receptor 1 (, CXC1) * chemokine (C-X3-C motif) receptor 1 (, C3X1) *

GPR137B G protein-coupled receptor 137B also known as GPR137B is a G protein-coupled receptor which in humans is encoded by the ''GPR137B'' gene In biology, the word gene (from , ; "... Wilhelm Johannsen coined the word gene to describe the Mendel ...

(, TM7SF1)

Subfamily A2

** Chemokine (C-C motif) receptor-like 1 (, CCR11) ** Chemokine (C-C motif) receptor 6 (, CKR6) ** Chemokine (C-C motif) receptor 7 (, CKR7) ** Chemokine (C-C motif) receptor 9 (, CKR9) ** Chemokine (C-C motif) receptor 10 (, CKRA) *

CXC chemokine receptors CXC chemokine receptors are integral membrane proteins that specifically bind and respond to cytokines of the CXC chemokine family. They represent one subfamily of chemokine receptors, a large family of G protein-linked receptors that are k ...

** Chemokine (C-X-C motif) receptor 3 () ** Chemokine (C-X-C motif) receptor 4 (, Fusin) ** Chemokine (C-X-C motif) receptor 5 () ** Chemokine (C-X-C motif) receptor 6 (, BONZO) ** Chemokine (C-X-C motif) receptor 7 (, RDC1) *

Interleukin-8 Interleukin 8 (IL-8 or chemokine (C-X-C motif) ligand 8, CXCL8) is a chemokine produced by macrophages and other cell types such as epithelial cells, airway smooth muscle cells and endothelial cells. Endothelial cells store IL-8 in their stora ...

(IL8R) ** IL8R-α (, CXCR1) ** IL8R-β (, CXCR2) *

Adrenomedullin receptor Calcitonin receptor-like (CALCRL), also known as the calcitonin receptor-like receptor (CRLR), is a human protein; it is a receptor for calcitonin gene-related peptide. Function The protein encoded by the CALCRL gene is a G protein-coupled re ...

() * Duffy blood group, chemokine receptor (, DUFF) * G Protein-coupled Receptor 30 (, CML2, GPCR estrogen receptor)

Subfamily A3

* Angiotensin II receptor ** Angiotensin II receptor, type 1 (, AG2S) ** Angiotensin II receptor, type 2 (, AG22) **

Apelin receptor The Apelin Receptor (APLNR, also known as APJ) is a G protein-coupled receptor. APLNR possesses two endogenous ligands which are APELIN Apelin (also known as APLN) is a peptide that in humans is encoded by the ''APLN'' gene. Apelin is one of t ...

(, APJ) * Bradykinin receptor **

Bradykinin receptor B1 Bradykinin receptor B1 (B1) is a G-protein coupled receptor encoded by the BDKRB1 gene in humans. Its principal ligand is bradykinin, a 9 amino acid peptide generated in pathophysiologic conditions such as inflammation, trauma, burns, shock, and a ...

(, BRB1) ** Bradykinin receptor B2 (, BRB2) *

GPR15 G protein-coupled receptor 15 is a protein that in humans is encoded by the GPR15 gene. GPR15 is a class A orphan G protein-coupled receptor (heterotrimeric guanine nucleotide-binding protein, GPCR). The ''GPR15'' gene is localized at chromosome ...

(, GPRF) *

GPR25 Probable G-protein coupled receptor 25 is a protein that in humans is encoded by the ''GPR25'' gene In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''ge ...

()

Subfamily A4

Opioid receptor Opioid receptors are a group of inhibitory G protein-coupled receptors with opioids as ligands. The endogenous opioids are dynorphins, enkephalins, endorphins, endomorphins and nociceptin. The opioid receptors are ~40% identical to somatosta ...

delta Opioid receptor Delta commonly refers to: * Delta (letter) (Δ or δ), a letter of the Greek alphabet * River delta, at a river mouth * D ( NATO phonetic alphabet: "Delta") * Delta Air Lines, US * Delta variant of SARS-CoV-2 that causes COVID-19 Delta may als ...

(, OPRD) **

kappa Opioid receptor Kappa (uppercase Κ, lowercase κ or cursive ; el, κάππα, ''káppa'') is the 10th letter of the Greek alphabet, representing the voiceless velar plosive sound in Ancient and Modern Greek. In the system of Greek numerals, has a value ...

(, OPRK) ** mu Opioid receptor (, OPRM) **

Nociceptin receptor The nociceptin opioid peptide receptor (NOP), also known as the nociceptin/orphanin FQ (N/OFQ) receptor or kappa-type 3 opioid receptor, is a protein that in humans is encoded by the ''OPRL1'' (opioid receptor-like 1) gene. The nociceptin receptor ...

(, OPRX) *

Somatostatin receptor Somatostatin receptors are receptors for the ligand somatostatin, a small neuropeptide associated with neural signaling, particularly in the post-synaptic response to NMDA receptor co-stimulation/activation. Somatostatin is encoded by a CRE ...

Somatostatin receptor 1 Somatostatin receptor type 1 is a protein that in humans is encoded by the ''SSTR1'' gene. Function Somatostatin acts at many sites to inhibit the release of many hormones and other secretory proteins. The biological effects of somatostatin ar ...

(, SSR1) **

Somatostatin receptor 2 Somatostatin receptor type 2 is a protein that in humans is encoded by the ''SSTR2'' gene. The SSTR2 gene is located on chromosome 17 on the long arm in position 25.1 in humans. It is also found in most other vertebrates. The somatostatin recep ...

(, SSR2) **

Somatostatin receptor 3 Shekel Somatostatin receptor type 3 is a protein that in humans is encoded by the ''SSTR3'' gene. Function Somatostatin acts at many sites to inhibit the release of many hormones and other secretory proteins. The biological effects of somatos ...

(, SSR3) **

Somatostatin receptor 4 Somatostatin receptor type 4 is a protein that in humans is encoded by the ''SSTR4'' gene In biology, the word gene (from , ; "... Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation' ...

(, SSR4) **

Somatostatin receptor 5 Somatostatin receptor type 5 is a protein that in humans is encoded by the ''SSTR5'' gene. Somatostatin acts at many sites to inhibit the release of many hormones and other secretory proteins. The biological effects of somatostatin are probably ...

(, SSR5) *

GPCR neuropeptide receptor GPCR neuropeptide receptors are G-protein coupled receptors which bind various neuropeptides. Members include: * Neuropeptide B/W receptor ** NPBWR1 ** NPBWR2 * Neuropeptide FF receptor ** NPFFR1 ** NPFFR2 * Neuropeptide S receptor ** NPSR1 ...

Neuropeptides B/W receptor 1 Neuropeptides B/W receptor 1, also known as NPBW1 and GPR7, is a human protein encoded by the NPBWR1 gene. As implied by its name, it and related gene NPBW2 (with which it shares 70% nucleotide identity) are transmembranes protein that bind Neur ...

(, GPR7) ** Neuropeptides B/W receptor 2 (, GPR8) * GPR1 orphan receptor ()

Subfamily A5

Galanin receptor The galanin receptor is a G protein-coupled receptor, or metabotropic receptor which binds galanin. Galanin receptors can be found throughout the peripheral and central nervous systems and the endocrine system. So far three subtypes are known ...

** Galanin receptor 1 (, GALR) ** Galanin receptor 2 (, GALS) **

Galanin receptor 3 Galanin receptor 3 (GAL3) is a G-protein coupled receptor encoded by the GALR3 gene. Function The neuropeptide galanin modulates a variety of physiologic processes including cognition/memory, sensory/pain processing, hormone secretion, and feed ...

(, GALT) * Cysteinyl leukotriene receptor ** Cysteinyl leukotriene receptor 1 () **

Cysteinyl leukotriene receptor 2 Cysteinyl leukotriene receptor 2, also termed CYSLTR2, is a receptor for cysteinyl leukotrienes (LT) (see leukotrienes#Cysteinyl leukotrienes). CYSLTR2, by binding these cysteinyl LTs (CysLTs; viz, LTC4, LTD4, and to a much lesser extent, LT ...

() *

Leukotriene B4 receptor The leukotriene B4 receptors (BLTRs) include the following two receptors: * Leukotriene B4 receptor 1 (BLTR1) * Leukotriene B4 receptor 2 (BLTR2) See also * Eicosanoid receptor Most of the eicosanoid receptors are integral membrane protein G ...

(, P2Y7) **

Leukotriene B4 receptor 2 Leukotriene B4 receptor 2, also known as BLT2, BLT2 receptor, and BLTR2, is an Integral membrane protein that is encoded by the LTB4R2 gene in humans and the Ltbr2 gene in mice. Discovered several years after the leukotriene B4 receptor 1 (BLT1) ...

() *

Relaxin receptor The relaxin receptors are a subclass of four closely related G protein-coupled receptors (GPCR) that bind relaxin peptide hormones. Below is list of human relaxin receptors, their endogenous peptide hormones, and what downstream enzymes are ac ...

Relaxin/insulin-like family peptide receptor 1 Relaxin/insulin-like family peptide receptor 1, also known as RXFP1, is a human G protein coupled receptor that is one of the relaxin receptors. It is a rhodopsin-like GPCR which is unusual in this class as it contains a large extracellular bindin ...

(, LGR7) **

Relaxin/insulin-like family peptide receptor 2 Relaxin/insulin-like family peptide receptor 2, also known as RXFP2, is a human G-protein coupled receptor. The receptors for glycoprotein hormones such as follicle-stimulating hormone (FSH; see MIM 136530) and thyroid-stimulating hormone (TSH; s ...

(, GPR106) ** Relaxin/insulin-like family peptide receptor 3 (, SALPR) ** Relaxin/insulin-like family peptide receptor 4 (, GPR100/GPR142) *

KiSS1-derived peptide receptor The KiSS1-derived peptide receptor (also known as GPR54 or the Kisspeptin receptor) is a G protein-coupled receptor which binds the peptide hormone kisspeptin (metastin). Kisspeptin is encoded by the metastasis suppressor gene KISS1, which is ex ...

(GPR54) () *

Melanin-concentrating hormone receptor 1 Melanin-concentrating hormone receptor 1, also known as MCH1, is one of the melanin-concentrating hormone receptors found in all mammals. The protein encoded by this gene, a member of the G protein-coupled receptor family 1, is an integral plasma ...

(, GPRO) * Urotensin-II receptor (, UR2R)

Subfamily A6

* Cholecystokinin receptor **

Cholecystokinin A receptor The Cholecystokinin A receptor is a human protein, also known as CCKAR or CCK1, with CCK1 now being the IUPHAR-recommended name. Function This gene encodes a G-protein coupled receptor that binds sulfated members of the cholecystokinin (CCK) ...

(, CCKR) **

Cholecystokinin B receptor The cholecystokinin B receptor also known as CCKBR or CCK2 is a protein that in humans is encoded by the ''CCKBR'' gene. This gene encodes a G protein-coupled receptor for gastrin and cholecystokinin (CCK), regulatory peptides of the brain and ga ...

(, GASR) *

Neuropeptide FF receptor The neuropeptide FF receptors are members of the G-protein coupled receptor superfamily of integral membrane proteins which bind the pain modulatory neuropeptides AF and FF. The Neuropeptide FF receptor family is a member of the G protein-coupled ...

Neuropeptide FF receptor 1 Neuropeptide FF receptor 1, also known as NPFF1 is a human protein, encoded by the NPFFR1 gene In biology, the word gene (from , ; "... Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''genera ...

(, FF1R) **

Neuropeptide FF receptor 2 Neuropeptide FF receptor 2, also known as NPFF2 is a human protein encoded by the NPFFR2 gene. See also * Neuropeptide FF receptor The neuropeptide FF receptors are members of the G-protein coupled receptor superfamily of integral membrane prot ...

(, FF2R) *

Orexin receptor The orexin receptor (also referred to as the hypocretin receptor) is a G-protein-coupled receptor that binds the neuropeptide orexin. There are two variants, OX1 and OX2, each encoded by a different gene (, ). Both orexin receptors exhibit ...

Hypocretin (orexin) receptor 1 Orexin receptor type 1 (Ox1R or OX1), also known as hypocretin receptor type 1 (HcrtR1), is a protein that in humans is encoded by the HCRTR1 gene. Function The orexin 1 receptor (OX1), is a G-protein coupled receptor that is heavily expresse ...

(, OX1R) **

Hypocretin (orexin) receptor 2 Orexin receptor type 2 (Ox2R or OX2), also known as hypocretin receptor type 2 (HcrtR2), is a protein that in humans is encoded by the HCRTR2 gene. Structure The structure of the receptor has been solved to 2.5 Å resolution as a fusion prote ...

(, OX2R) *

Vasopressin receptor The actions of vasopressin are mediated by stimulation of tissue-specific G protein-coupled receptors (GPCRs) called vasopressin receptors that are classified into the V1 (V1A), V2, and V3 (V1B) receptor subtypes. These three subtypes differ ...

Arginine vasopressin receptor 1A Vasopressin receptor 1A (V1AR), or arginine vasopressin receptor 1A (officially called AVPR1A) is one of the three major receptor types for vasopressin ( AVPR1B and AVPR2 being the others), and is present throughout the brain, as well as in the p ...

(, V1AR) **

Arginine vasopressin receptor 1B Vasopressin V1b receptor (V1BR) also known as vasopressin 3 receptor (VPR3) or antidiuretic hormone receptor 1B is a protein that in humans is encoded by the ''AVPR1B'' (arginine vasopressin receptor 1B) gene. V1BR acts as a receptor for vasopre ...

(, V1BR) **

Arginine vasopressin receptor 2 Vasopressin receptor 2 (V2R), or arginine vasopressin receptor 2 (officially called AVPR2), is a protein that acts as receptor for vasopressin. AVPR2 belongs to the subfamily of G-protein-coupled receptors. Its activity is mediated by the Gs t ...

(, V2R) **

Oxytocin receptor The oxytocin receptor, also known as OXTR, is a protein which functions as receptor for the hormone and neurotransmitter oxytocin. In humans, the oxytocin receptor is encoded by the ''OXTR'' gene which has been localized to human chromosome 3p25 ...

() * Gonadotropin releasing hormone receptor (, GRHR) * Pyroglutamylated RFamide peptide receptor (, GPR103) *

GPR22 Probable G-protein coupled receptor 22 is a protein that in humans is encoded by the ''GPR22'' gene In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''ge ...

(, GPRM) * GPR176 (, GPR)

Subfamily A7

* Bombesin receptor **

Bombesin-like receptor 3 The bombesin receptor subtype 3 also known as BRS-3 or BB3 is a protein which in humans is encoded by the ''BRS3'' gene. Function Mammalian bombesin-like peptides are widely distributed in the central nervous system as well as in the gastroin ...

() ** Neuromedin B receptor () ** Gastrin-releasing peptide receptor () *

Endothelin receptor There are at least four known endothelin receptors, ETA, ETB1, ETB2 and ETC, all of which are G protein-coupled receptors whose activation result in elevation of intracellular-free calcium, which constricts the smooth muscles of the blood vessels ...

Endothelin receptor type A Endothelin receptor type A, also known as ETA, is a human G protein-coupled receptor. Interactions Endothelin receptor type A has been shown to interact with HDAC7A and HTATIP. See also * Endothelin receptor There are at least four kno ...

(, ET1R) **

Endothelin receptor type B Endothelin receptor type B, also known as ETB is a protein that in humans is encoded by the ''EDNRB'' gene. Function Endothelin receptor type B is a G protein-coupled receptor which activates a phosphatidylinositol-calcium second messenger ...

(, ETBR) **

GPR37 Probable G-protein coupled receptor 37 is a protein that in humans is encoded by the ''GPR37'' gene. Interactions GPR37 has been shown to interact with HSPA1A and Parkin (ligase). GPR37 is a receptor for prosaposin. It was previously thought t ...

(, ETBR-LP2) * Neuromedin U receptor ** Neuromedin U receptor 1 () ** Neuromedin U receptor 2 () *

Neurotensin receptor Neurotensin receptors are transmembrane receptors that bind the neurotransmitter A neurotransmitter is a signaling molecule secreted by a neuron to affect another cell across a synapse. The cell receiving the signal, any main body part or t ...

** Neurotensin receptor 1 (, NTR1) ** Neurotensin receptor 2 (, NTR2) *

Thyrotropin-releasing hormone receptor Thyrotropin-releasing hormone receptor (TRHR) is a G protein-coupled receptor which binds thyrotropin-releasing hormone. The TRHR is found on the cell membrane of thyrotropes of the anterior pituitary. When the TRHR binds TRH it activates phosph ...

(, TRFR) *

Growth hormone secretagogue receptor Growth hormone secretagogue receptor(GHS-R), also known as ghrelin receptor, is a G protein-coupled receptor that binds growth hormone secretagogues (GHSs), such as ghrelin, the "hunger hormone". The role of GHS-R is thought to be in regulating en ...

() * GPR39 () *

Motilin receptor Motilin receptor is a G protein-coupled receptor that binds motilin. Motilin in turn is an intestinal peptide that stimulates contraction of gut smooth muscle Smooth muscle is an involuntary non- striated muscle, so-called because it has no s ...

(, GPR38)

Subfamily A8

Anaphylatoxin receptors The anaphylatoxin receptors are a group of G-protein coupled receptors which bind anaphylatoxins. Members of this family include: * C3a receptor * C5a receptor The C5a receptor also known as complement component 5a receptor 1 (C5AR1) or CD88 ...

** C3a receptor (, C3AR) **

C5a receptor The C5a receptor also known as complement component 5a receptor 1 (C5AR1) or CD88 (Cluster of Differentiation 88) is a G protein-coupled receptor for C5a. It functions as a complement receptor. C5a receptor modulates inflammatory responses, obe ...

(, C5AR) ** Chemokine-like receptor 1 (, CML1) *

Formyl peptide receptor The formyl peptide receptors (FPR) belong to a class of G protein-coupled receptors involved in chemotaxis. In humans, there are three formyl peptide receptor isoforms, each encoded by a separate gene that are named FPR1, FPR2, and FPR3. T ...

Formyl peptide receptor 1 Formyl peptide receptor 1 (FPR1, FPR1 receptor, fMet-Leu-Phe receptor 1, FMLP receptor 1, or N-formylmethionyl-leucyl-phenylalanine receptor 1) is a cell surface receptor protein that in humans is encoded by the ''formyl peptide receptor 1'' (' ...

(, FMLR) **

Formyl peptide receptor-like 1 N-formyl peptide receptor 2 (FPR2) is a G-protein coupled receptor (GPCR) located on the surface of many cell types of various animal species. The human receptor protein is encoded by the ''FPR2'' gene and is activated to regulate cell functio ...

(, FML2) **

Formyl peptide receptor-like 2 N-formyl peptide receptor 3 (FPR3) is a receptor protein that in humans is encoded by the ''FPR3'' gene. Nomenclature note Confusingly, there are two nomenclatures for FPR receptors and their genes, the first one used, FPR, FPR1, and FPR2 and i ...

(, FML1) *

MAS1 oncogene The MAS1 oncogene (MAS receptor) is a G protein-coupled receptor which binds the angiotensin II metabolite angiotensin (1-7). The MAS1 receptor, when activated by binding angiotensin-(1-7), opposes many of the effects of the angiotensin II rece ...

** MAS1 (, MAS) ** MAS1L (, MRG) * GPR1 () *

GPR32 G protein-coupled receptor 32, also known as GPR32 or the RvD1 receptor, is a human receptor (biochemistry) belonging to the rhodopsin-like subfamily of G protein-coupled receptors. Gene The ''GPR32'' was initially identified and defined by mo ...

(, GPRW) * GPR44 () * GPR77 (, C5L2)

Subfamily A9

Melatonin receptor Melatonin receptors are G protein-coupled receptors (GPCR) which bind melatonin. Three types of melatonin receptors have been cloned. The MT1 (or Mel1A or MTNR1A) and MT2 (or Mel1B or MTNR1B) receptor subtypes are present in humans and other ...

Melatonin receptor 1A Melatonin receptor type 1A is a protein that in humans is encoded by the ''MTNR1A'' gene. Function This gene encodes the MT1 protein, one of two high-affinity forms of a receptor for melatonin, the primary hormone secreted by the pineal gland. ...

(, ML1A) **

Melatonin receptor 1B Melatonin receptor 1B, also known as MTNR1B, is a protein that in humans is encoded by the ''MTNR1B'' gene. Function This gene encodes the MT2 protein, one of two high-affinity forms of a receptor for melatonin, the primary hormone secreted by ...

(, ML1B) * Neurokinin receptor ** Tachykinin receptor 1 (, NK1R) **

Tachykinin receptor 2 Substance-K receptor is a protein that in humans is encoded by the ''TACR2'' gene. Function This gene belongs to a family of genes that function as receptors for tachykinins. Receptor affinities are specified by variations in the 5'-end of th ...

(, NK2R) **

Tachykinin receptor 3 Tachykinin receptor 3, also known as TACR3, is a protein which in humans is encoded by the ''TACR3'' gene. Function This gene belongs to a family of genes that function as receptors for tachykinins. Receptor affinities are specified by varia ...

(, NK3R) *

Neuropeptide Y receptor Neuropeptide Y receptors are a family of receptors belonging to class A G-protein coupled receptors and they are activated by the closely related peptide hormones neuropeptide Y, peptide YY and pancreatic polypeptide. These receptors are invo ...

** Neuropeptide Y receptor Y1 (, NY1R) ** Neuropeptide Y receptor Y2 (, NY2R) ** Pancreatic polypeptide receptor 1 (, NY4R) **

Neuropeptide Y receptor Y5 Neuropeptide Y receptor type 5 is a protein that in humans is encoded by the ''NPY5R'' gene. Selective ligands Agonists * Neuropeptide Y (endogenous agonist, non subtype selective) * BWX-46 (selective NPY5 agonist, CAS# 172997-92-1) * Pe ...

(, NY5R) * Prolactin-releasing peptide receptor ( PRLHR, GPRA) *

Prokineticin receptor 1 Prokineticin receptor 1, also known as PKR1, is a human protein encoded by the PROKR1 gene In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation' ...

(, GPR73) *

Prokineticin receptor 2 Prokineticin receptor 2 (PKR2), is a dimeric G protein-coupled receptor encoded by the PROKR2 gene in humans. Function Prokineticins are secreted proteins that can promote angiogenesis and induce strong gastrointestinal smooth muscle contracti ...

(, PKR2) * GPR19 (, GPRJ) *

GPR50 G protein-coupled receptor 50 is a protein which in humans is encoded by the ''GPR50'' gene. Function GPR50 is a member of the G protein-coupled receptor family of integral membrane proteins and is most closely related to the melatonin receptor ...

(, ML1X) * GPR75 () * GPR83 (, GPR72)

Subfamily A10

* Glycoprotein hormone receptor **

FSH-receptor The follicle-stimulating hormone receptor or FSH receptor (FSHR) is a transmembrane receptor that interacts with the follicle-stimulating hormone (FSH) and represents a G protein-coupled receptor (GPCR). Its activation is necessary for the hormo ...

() **

Luteinizing hormone/choriogonadotropin receptor The luteinizing hormone/choriogonadotropin receptor (LHCGR), also lutropin/choriogonadotropin receptor (LCGR) or luteinizing hormone receptor (LHR) is a transmembrane receptor found predominantly in the ovary and testis, but also many extragonad ...

(, LSHR) **

Thyrotropin receptor The thyrotropin receptor (or TSH receptor) is a receptor (and associated protein) that responds to thyroid-stimulating hormone (also known as "thyrotropin") and stimulates the production of thyroxine (T4) and triiodothyronine (T3). The TSH recep ...

() * Leucine-rich repeat-containing G protein-coupled receptor 4 (, GPR48) * Leucine-rich repeat-containing G protein-coupled receptor 5 (, GPR49) * Leucine-rich repeat-containing G protein-coupled receptor 6 ()

Subfamily A11

* GPR40-related receptor **

Free fatty acid receptor 1 Free fatty acid receptor 1 (FFA1), also known as GPR40, is a class A G-protein coupled receptor that in humans is encoded by the FFAR1 gene. It is strongly expressed in the cells of the pancreas and to a lesser extent in the brain. This membran ...

(, GPR40) **

Free fatty acid receptor 2 Free fatty acid receptor 2 (FFA2) is a G-protein coupled receptor encoded by the ''FFAR2'' gene. Expression ''FFAR2'' mRNA is expressed in adipose tissue, pancreas, spleen, lymph nodes, bone marrow, and peripheral blood mononuclear cells. ''FFAR2 ...

(, GPR43) **

Free fatty acid receptor 3 Free fatty acid receptor 3 (FFA3) is a G-protein coupled receptor that in humans is encoded by the ''FFAR3'' gene. Animal studies Knockout mouse studies have implicated FFAR3 in diabetes, colitis, hypertension and asthma. However, discrepancies ...

(, GPR41) **

GPR42 Putative G-protein coupled receptor 42 (previously termed FFAR1L, FFAR3L, GPR41L, and GPR42P) is a protein that in humans is encoded by the ''GPR42'' gene. The human GPR gene is located at the same site as the human ''FFAR1, FFAR,'' and ''FFAR3'' ...

(, FFAR1L) * P2 purinoceptor ** Purinergic receptor P2Y₁ () ** Purinergic receptor P2Y₂ () ** Purinergic receptor P2Y₄ () ** Purinergic receptor P2Y₆ () ** Purinergic receptor P2Y₈ () ** Purinergic receptor P2Y₁₁ () * Hydroxycarboxylic acid receptor 1 (, GPR81) * Hydroxycarboxylic acid receptor 2, Niacin receptor 1 (, GPR109A) * Hydroxycarboxylic acid receptor 3, Niacin receptor 2 (, GPR109B, HM74) *

GPR31 G-protein coupled receptor 31 also known as 12-(S)-HETE receptor is a protein that in humans is encoded by the ''GPR31'' gene. The human gene is located on chromosome 6q27 and encodes a G-protein coupled receptor protein composed of 319 amino aci ...

(, GPRV) *

GPR82 Probable G-protein coupled receptor 82 is a protein that in humans is encoded by the ''GPR82'' gene In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''ge ...

() * Oxoglutarate (alpha-ketoglutarate) receptor 1 (, GPR80) * Succinate receptor 1 (, GPR91)

Subfamily A12

* P2 purinoceptor ** Purinergic receptor P2Y₁₂ () ** Purinergic receptor P2Y₁₃ (, GPR86) ** Purinergic receptor P2Y₁₄ (, UDP-glucose receptor, KI01) *

GPR34 Probable G-protein coupled receptor 34 is a protein that in humans is encoded by the ''GPR34'' gene In biology, the word gene (from , ; "... Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''g ...

() *

GPR87 Probable G-protein coupled receptor 87 is a protein that in humans is encoded by the ''GPR87'' gene In biology, the word gene (from , ; "... Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''g ...

() *

GPR171 Probable G-protein coupled receptor 171 is a protein that in humans is encoded by the ''GPR171'' gene In biology, the word gene (from , ; "... Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ' ...

(, H963) * Platelet-activating factor receptor (, PAFR)

Subfamily A13

Cannabinoid receptor Cannabinoid receptors, located throughout the body, are part of the endocannabinoid system a class of cell membrane receptors in the G protein-coupled receptor superfamily. As is typical of G protein-coupled receptors, the cannabinoid recep ...

Cannabinoid receptor 1 (brain) Cannabinoid receptor type 1 (CB1), also known as cannabinoid receptor 1, is a G protein-coupled cannabinoid receptor that in humans is encoded by the ''CNR1'' gene. The human CB1 receptor is expressed in the peripheral nervous system and centr ...

(, CB1R) ** Cannabinoid receptor 2 (macrophage) (, CB2R) * Lysophosphatidic acid receptor ** Lysophosphatidic acid receptor 1 () ** Lysophosphatidic acid receptor 2 () ** Lysophosphatidic acid receptor 3 () * Sphingosine 1-phosphate receptor ** Sphingosine 1-phosphate receptor 1 () ** Sphingosine 1-phosphate receptor 2 () ** Sphingosine 1-phosphate receptor 3 () ** Sphingosine 1-phosphate receptor 4 () ** Sphingosine 1-phosphate receptor 5 () * Melanocortin/ACTH receptor **

Melanocortin 1 receptor The melanocortin 1 receptor (MC1R), also known as melanocyte-stimulating hormone receptor (MSHR), melanin-activating peptide receptor, or melanotropin receptor, is a G protein–coupled receptor that binds to a class of pituitary peptide hormones ...

(, MSHR) **

Melanocortin 3 receptor Melanocortin 3 receptor (MC3R) is a protein that in humans is encoded by the gene. Function This gene encodes MC3R, a G-protein coupled receptor (GPCR) for melanocyte-stimulating hormone (MSH) and adrenocorticotropic hormone (ACTH) that is exp ...

() **

Melanocortin 4 receptor Melanocortin 4 receptor (MC4R) is a melanocortin receptor that in humans is encoded by the gene. It encodes the MC4R protein, a G protein-coupled receptor (GPCR) that binds α-melanocyte stimulating hormone (α-MSH). In mouse models, MC4 recepto ...

() **

Melanocortin 5 receptor Melanocortin 5 receptor (MC5R) is a protein that in humans is encoded by the gene. It is located on the chromosome 18 in the human genome. When the MC5R was disrupted in transgenic mice, it induced disruption of their exocrine glands and resulted ...

() **

ACTH receptor The adrenocorticotropic hormone receptor or ACTH receptor also known as the melanocortin receptor 2 or MC2 receptor is a type of melanocortin receptor (type 2) which is specific for ACTH. A G protein–coupled receptor located on the external ce ...

(), ACTR) * GPR3 () * GPR6 () * GPR12 (, GPRC)

Subfamily A14

Eicosanoid receptor Most of the eicosanoid receptors are integral membrane protein G protein-coupled receptors (GPCRs) that bind and respond to eicosanoid signaling molecules. Eicosanoids are rapidly metabolized to inactive products and therefore are short-lived. A ...

** Prostaglandin D₂ receptor (, PD2R) ** Prostaglandin E₁ receptor (, PE21) ** Prostaglandin E₂ receptor (, PE22) ** Prostaglandin E₃ receptor (, PE23) ** Prostaglandin E₄ receptor (, PE24) **

Prostaglandin F receptor Prostaglandin F receptor (FP) is a receptor (biochemistry), receptor belonging to the prostaglandin receptor, prostaglandin (PG) group of receptors. FP binds to and mediates the biological actions of Prostaglandin F2alpha, Prostaglandin F2α (PG ...

(, PF2R) ** Prostaglandin I₂ (prostacyclin) receptor (, PI2R) ** Thromboxane A₂ receptor (, TA2R)

Subfamily A15

* Lysophosphatidic acid receptor ** Lysophosphatidic acid receptor 4 () ** Lysophosphatidic acid receptor 5 () ** Lysophosphatidic acid receptor 6 () * P2 purinoceptor ** Purinergic receptor P2Y₁₀ (, P2Y10) *

Protease-activated receptor Protease-activated receptors (PAR) are a subfamily of related G protein-coupled receptors that are activated by cleavage of part of their extracellular domain. They are highly expressed in platelets, and also on endothelial cells, myocytes an ...

** Coagulation factor II (thrombin) receptor-like 1 (, PAR2) ** Coagulation factor II (thrombin) receptor-like 2 (, PAR3) ** Coagulation factor II (thrombin) receptor-like 3 (, PAR4) * Epstein-Barr virus induced gene 2 (lymphocyte-specific G protein-coupled receptor) () *

Proton-sensing G protein-coupled receptors Proton-sensing G protein-coupled receptors are transmembrane receptors which sense acidic pH and include GPR132 (G2A), GPR4, GPR68 (OGR1) and GPR65 (TDAG8). These G protein-coupled receptors are activated when extracellular pH falls into the rang ...

GPR4 G-protein coupled receptor 4 is a protein that in humans is encoded by the ''GPR4'' gene. See also *Proton-sensing G protein-coupled receptors Proton-sensing G protein-coupled receptors are transmembrane receptors which sense acidic pH and incl ...

() ** GPR65 () ** GPR68 () **

GPR132 G protein coupled receptor 132, also termed G2A, is classified as a member of the proton sensing G protein coupled receptor (GPR) subfamily. Like other members of this subfamily, i.e. GPR4, GPR68 (OGR1), and GPR65 (TDAG8), G2A is a G protein c ...

(, G2A) *

GPR17 Uracil nucleotide/cysteinyl leukotriene receptor is a G protein-coupled receptor that in humans is encoded by the ''GPR17'' gene located on chromosome 2 at position q21. The actual activating ligands for and some functions of this receptor are d ...

(, GPRH) *

GPR18 ''N''-Arachidonyl glycine receptor (NAGly receptor), also known as G protein-coupled receptor 18 (GPR18), is a protein that in humans is encoded by the ''GPR18'' gene. Along with the other previously "orphan" receptors GPR55 and GPR119, GPR18 has ...

(, GPRI) * GPR20 (, GPRK) *

GPR35 G protein-coupled receptor 35 also known as GPR35 is a G protein-coupled receptor which in humans is encoded by the ''GPR35'' gene. Heightened expression of GPR35 is found in immune and gastrointestinal tissues, including the crypts of Lieberküh ...

() *

GPR55 G protein-coupled receptor 55 also known as GPR55 is a G protein-coupled receptor that in humans is encoded by the ''GPR55'' gene. GPR55, along with GPR119 and GPR18, have been implicated as novel cannabinoid receptors. History GPR55 was ...

() *

Coagulation factor II receptor Proteinase-activated receptor 1 (PAR1) also known as protease-activated receptor 1 or coagulation factor II (thrombin) receptor is a protein that in humans is encoded by the ''F2R'' gene. PAR1 is a G protein-coupled receptor and one of four prote ...

(, THRR)

Subfamily A16

Opsin Animal opsins are G-protein-coupled receptors and a group of proteins made light-sensitive via a chromophore, typically retinal. When bound to retinal, opsins become Retinylidene proteins, but are usually still called opsins regardless. Most pro ...

s **

Rhodopsin Rhodopsin, also known as visual purple, is a protein encoded by the RHO gene and a G-protein-coupled receptor (GPCR). It is the opsin of the rod cells in the retina and a light-sensitive receptor protein that triggers visual phototransduct ...

(, OPSD) ** Opsin 1 (cone pigments), short-wave-sensitive (color blindness, tritan) (, OPSB) (blue-sensitive opsin) ** Opsin 1 (cone pigments), medium-wave-sensitive (color blindness, deutan) (, OPSG) (green-sensitive opsin) ** Opsin 1 (cone pigments), long-wave-sensitive (color blindness, protan) (, OPSR) (red-sensitive opsin) ** Opsin 3, Panopsin () ** Opsin 4, Melanopsin () ** Opsin 5 (, GPR136) **

Retinal G protein coupled receptor RPE-retinal G protein-coupled receptor also known as RGR-opsin is a protein that in humans is encoded by the ''RGR'' gene. RGR-opsin is a member of the rhodopsin-like receptor subfamily of GPCR. Like other opsins which bind retinaldehyde, it cont ...

() ** Retinal pigment epithelium-derived rhodopsin homolog (, OPSX) (visual pigment-like receptor opsin)

Subfamily A17

* 5-Hydroxytryptamine (5-HT) receptor ** 5-HT_2A (, 5H2A) ** 5-HT_2B (, 5H2B) ** 5-HT_2C (, 5H2C) ** 5-HT₆ (, 5H6) *

Adrenergic receptor The adrenergic receptors or adrenoceptors are a class of G protein-coupled receptors that are targets of many catecholamines like norepinephrine (noradrenaline) and epinephrine (adrenaline) produced by the body, but also many medications like beta ...

** Alpha_1A (, A1AA) ** Alpha_1B (, A1AB) ** Alpha_1D (, A1AD) ** Alpha_2A (, A2AA) ** Alpha_2B (, A2AB) ** Alpha_2C (, A2AC) ** Beta₁ (, B1AR) ** Beta₂ (, B2AR) ** Beta₃ (, B3AR) *

Dopamine receptor Dopamine receptors are a class of G protein-coupled receptors that are prominent in the vertebrate central nervous system (CNS). Dopamine receptors activate different effectors through not only G-protein coupling, but also signaling through diffe ...

** D₁ (, DADR) ** D₂ (, D2DR) ** D₃ (, D3DR) ** D₄ (, D4DR) ** D₅ (, DBDR) *

Trace amine receptor Trace amine-associated receptors (TAARs), sometimes referred to as trace amine receptors (TAs or TARs), are a class of G protein-coupled receptors that were discovered in 2001. TAAR1, the first of six functional human TAARs, has gained considerab ...

TAAR1 Trace amine-associated receptor 1 (TAAR1) is a trace amine-associated receptor (TAAR) protein that in humans is encoded by the ''TAAR1'' gene. TAAR1 is an intracellular amine-activated and G protein-coupled receptor (GPCR) that is primarily ex ...

(, TAR1) ** TAAR2 (, GPR58) **

TAAR3 Putative trace amine-associated receptor 3 (TAAR3) is a human pseudogene Pseudogenes are nonfunctional segments of DNA that resemble functional genes. Most arise as superfluous copies of functional genes, either directly by DNA duplication or ...

(, GPR57) ** TAAR5 (, PNR) **

TAAR6 Trace amine associated receptor 6, also known as TAAR6, is a protein which in humans is encoded by the ''TAAR6'' gene. Function TAAR6 belongs to the trace amine-associated receptor family. Trace amines are endogenous amine compounds that are c ...

(, TAR4) ** TAAR8 (, GPR102) ** TAAR9 (, TAR3) * Histamine H₂ receptor (, HH2R)

Subfamily A18

* Histamine H₁ receptor (, HH1R) * Histamine H₃ receptor () * Histamine H₄ receptor () *

Adenosine receptor The adenosine receptors (or P1 receptors) are a class of purinergic G protein-coupled receptors with adenosine as the endogenous ligand. There are four known types of adenosine receptors in humans: A1, A2A, A2B and A3; each is encoded by a dif ...

** A₁ (, AA1R) ** A_2a (, AA2A) ** A_2b (, AA2B) ** A₃ (, AA3R) *

Muscarinic acetylcholine receptor Muscarinic acetylcholine receptors, or mAChRs, are acetylcholine receptors that form G protein-coupled receptor, G protein-coupled receptor complexes in the cell membranes of certain neurons and other Cell (biology), cells. They play several r ...

** M₁ (, ACM1) ** M₂ (, ACM2) ** M₃ (, ACM3) ** M₄ (, ACM4) ** M₅ (, ACM5) *

GPR21 Probable G-protein coupled receptor 21 is a protein that in humans is encoded by the ''GPR21'' gene In biology, the word gene (from , ; "... Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''g ...

(, GPRL) *

GPR27 Probable G-protein coupled receptor 27 is a protein that in humans is encoded by the ''GPR27'' gene In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''ge ...

() * GPR45 (, PSP24) *

GPR52 Probable G-protein coupled receptor 52 is a protein that in humans is encoded by the ''GPR52'' gene. Members of the G protein-coupled receptor (GPR) family play important roles in signal transduction from the external environment to the inside of ...

() *

GPR61 Probable G-protein coupled receptor 61 is a protein that in humans is encoded by the ''GPR61'' gene In biology, the word gene (from , ; "... Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''g ...

() * GPR62 () * GPR63 () *

GPR78 Probable G-protein coupled receptor 78 is a protein that in humans is encoded by the ''GPR78'' gene. G protein-coupled receptors (GPCRs, or GPRs) contain 7 transmembrane domains and transduce extracellular signals through heterotrimeric G protei ...

() * GPR84 () *

GPR85 Probable G-protein coupled receptor 85 is a protein that in humans is encoded by the ''GPR85'' gene In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''ge ...

() *

GPR88 Probable G-protein coupled receptor 88 is a protein that in humans is encoded by the ''GPR88'' gene In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''ge ...

() *

GPR101 Probable G-protein coupled receptor 101 is a protein that in humans is encoded by the ''GPR101'' gene. G protein-coupled receptors (GPCRs, or GPRs) contain 7 transmembrane domains and transduce extracellular signals through heterotrimeric G prote ...

() * GPR161 (, RE2) * GPR173 (, SREB3)

Subfamily A19

* 5-Hydroxytryptamine (5-HT) receptor ** 5-HT_1A (, 5H1A) ** 5-HT_1B (, 5H1B) ** 5-HT_1D (, 5H1D) ** 5-HT_1E (, 5H1E) ** 5-HT_1F (, 5H1F) ** 5-HT₄ () ** 5-HT_5A (, 5H5A) ** 5-HT₇ (, 5H7)

Unclassified

Olfactory receptor Olfactory receptors (ORs), also known as odorant receptors, are chemoreceptors expressed in the cell membranes of olfactory receptor neurons and are responsible for the detection of odorants (for example, compounds that have an odor) which give ri ...

Nematode chemoreceptor Nematode chemoreceptors are chemoreceptors of nematodes. Animals recognise a wide variety of chemicals using their senses of taste and smell. The nematode ''Caenorhabditis elegans'' has only 14 types of chemosensory neuron, yet is able to respon ...

(multiple, including ） *

Taste receptor A taste receptor or tastant is a type of cellular receptor which facilitates the sensation of taste. When food or other substances enter the mouth, molecules interact with saliva and are bound to taste receptors in the oral cavity and other loca ...

type 2 *

Vomeronasal receptor Vomeronasal receptors are a class of olfactory receptors that putatively function as receptors for pheromones. Pheromones have evolved in all animal phyla, to signal sex and dominance status, and are responsible for stereotypical social and se ...

type 1 **

VN1R1 Vomeronasal type-1 receptor 1 is a protein that in humans is encoded by the ''VN1R1'' gene. Function Pheromones are chemical signals that elicit specific behavioral responses and physiologic alterations in recipients of the same species. The p ...

VN1R2 Vomeronasal type-1 receptor 2 is a protein that in humans is encoded by the ''VN1R2'' gene In biology, the word gene (from , ; "... Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation ...

VN1R3 Vomeronasal type-1 receptor 3 is a protein that is encoded by the ''VN1R3'' gene In biology, the word gene (from , ; "... Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''bi ...

VN1R4 Vomeronasal type-1 receptor 4 is a protein that in humans is encoded by the ''VN1R4'' gene In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation' ...

VN1R5 Vomeronasal type-1 receptor 5 is a protein that in humans is encoded by the ''VN1R5'' gene In biology, the word gene (from , ; "... Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation ...

References

External links

* * This database includes multiple sequence alignments of all GPCR families and sub-families. {{G protein-coupled receptors G protein-coupled receptors Protein domains Protein families