GPR44

Prostaglandin D2 receptor 2
Identifiers
Symbols	PTGDR2; CD294; CRTH2; DL1R; DP2; GPR44
External IDs	OMIM: 604837 MGI: 1330275 HomoloGene: 3508 IUPHAR: DP2 ChEMBL: 5071 GeneCards: PTGDR2 Gene
Gene Ontology Molecular function • prostaglandin J receptor activity • G-protein coupled receptor activity • prostaglandin D receptor activity • prostaglandin F receptor activity • N-formyl peptide receptor activity Cellular component • plasma membrane • integral to plasma membrane Biological process • chemotaxis • immune response • G-protein coupled receptor signaling pathway • adenylate cyclase-inhibiting G-protein coupled receptor signaling pathway • calcium-mediated signaling • positive regulation of G-protein coupled receptor protein signaling pathway Sources: Amigo / QuickGO
RNA expression pattern
More reference expression data
Orthologs
Species	Human	Mouse
Entrez	11251	14764
Ensembl	ENSG00000183134	ENSMUSG00000034117
UniProt	Q9Y5Y4	Q9Z2J6
RefSeq (mRNA)	NM_004778	NM_009962
RefSeq (protein)	NP_004769	NP_034092
Location (UCSC)	Chr 11: 60.62 – 60.62 Mb	Chr 19: 10.94 – 10.94 Mb
PubMed search	[1]	[2]

G protein-coupled receptor 44 (GPR44) is a human protein. GPR44 has also been designated as CD294 (cluster of differentiation 294).

G protein-coupled receptors (GPCRs), such as GPR44, are integral membrane proteins containing 7 putative transmembrane domains (TMs). These proteins mediate signals to the interior of the cell via activation of heterotrimeric G proteins that in turn activate various effector proteins, ultimately resulting in a physiologic response.[supplied by OMIM]

GPR44 has recently been found to belong to the prostanoid receptor family and named DP₂, with this becoming the official IUPHAR nomenclature.

GPR44 has recently been found when activated by elevated level of prostaglandin D₂ (PGD₂), it could inhibit hair growth. This suggests the PGD2-GPR44 pathway as a potential target for bald treatment. A particularly promising compound for blocking the PGD2-GPR44 pathway is a compound known as TM-30089, which exhibits a "functional insurmountability" of PGD2 expression.

Further reading

• Nagata K (2004). "CRTH2". J. Biol. Regul. Homeost. Agents 17 (4): 334–7. PMID 15065763. 
• Chiba T, Kanda A, Ueki S et al. (2007). "Possible novel receptor for PGD2 on human bronchial epithelial cells". Int. Arch. Allergy Immunol. 143 Suppl 1: 23–7. doi:10.1159/000101400. PMID 17541272. 
• Nagata K, Tanaka K, Ogawa K et al. (1999). "Selective expression of a novel surface molecule by human Th2 cells in vivo". J. Immunol. 162 (3): 1278–86. PMID 9973380. 
• Marchese A, Sawzdargo M, Nguyen T et al. (1999). "Discovery of three novel orphan G-protein-coupled receptors". Genomics 56 (1): 12–21. doi:10.1006/geno.1998.5655. PMID 10036181. 
• Hirai H, Tanaka K, Yoshie O et al. (2001). "Prostaglandin D2 Selectively Induces Chemotaxis in T Helper Type 2 Cells, Eosinophils, and Basophils via Seven-Transmembrane Receptor Crth2". J. Exp. Med. 193 (2): 255–61. doi:10.1084/jem.193.2.255. PMC 2193345. PMID 11208866. 
• Hirai H, Tanaka K, Takano S et al. (2002). "Cutting edge: agonistic effect of indomethacin on a prostaglandin D2 receptor, CRTH2". J. Immunol. 168 (3): 981–5. PMID 11801628. 
• Iwasaki M, Nagata K, Takano S et al. (2002). "Association of a new-type prostaglandin D2 receptor CRTH2 with circulating T helper 2 cells in patients with atopic dermatitis". J. Invest. Dermatol. 119 (3): 609–16. doi:10.1046/j.1523-1747.2002.01862.x. PMID 12230502. 
• Strausberg RL, Feingold EA, Grouse LH et al. (2003). "Generation and initial analysis of more than 15,000 full-length human and mouse cDNA sequences". Proc. Natl. Acad. Sci. U.S.A. 99 (26): 16899–903. doi:10.1073/pnas.242603899. PMC 139241. PMID 12477932. 
• Böhm E, Sturm GJ, Weiglhofer I et al. (2004). "11-Dehydro-thromboxane B2, a stable thromboxane metabolite, is a full agonist of chemoattractant receptor-homologous molecule expressed on TH2 cells (CRTH2) in human eosinophils and basophils". J. Biol. Chem. 279 (9): 7663–70. doi:10.1074/jbc.M310270200. PMID 14668348. 
• Huang JL, Gao PS, Mathias RA et al. (2005). "Sequence variants of the gene encoding chemoattractant receptor expressed on Th2 cells (CRTH2) are associated with asthma and differentially influence mRNA stability". Hum. Mol. Genet. 13 (21): 2691–7. doi:10.1093/hmg/ddh279. PMID 15345705. 
• Gerhard DS, Wagner L, Feingold EA et al. (2004). "The Status, Quality, and Expansion of the NIH Full-Length cDNA Project: The Mammalian Gene Collection (MGC)". Genome Res. 14 (10B): 2121–7. doi:10.1101/gr.2596504. PMC 528928. PMID 15489334. 
• Venet F, Lepape A, Debard AL et al. (2004). "The Th2 response as monitored by CRTH2 or CCR3 expression is severely decreased during septic shock". Clin. Immunol. 113 (3): 278–84. doi:10.1016/j.clim.2004.07.005. PMID 15507393. 
• Gazi L, Gyles S, Rose J et al. (2005). "Delta12-prostaglandin D2 is a potent and selective CRTH2 receptor agonist and causes activation of human eosinophils and Th2 lymphocytes". Prostaglandins Other Lipid Mediat. 75 (1–4): 153–67. doi:10.1016/j.prostaglandins.2004.11.003. PMID 15789622. 
• Hata AN, Lybrand TP, Breyer RM (2005). "Identification of determinants of ligand binding affinity and selectivity in the prostaglandin D2 receptor CRTH2". J. Biol. Chem. 280 (37): 32442–51. doi:10.1074/jbc.M502563200. PMID 16030019. 
• Sandig H, Andrew D, Barnes AA et al. (2006). "9alpha,11beta-PGF2 and its stereoisomer PGF2alpha are novel agonists of the chemoattractant receptor, CRTH2". FEBS Lett. 580 (2): 373–9. doi:10.1016/j.febslet.2005.11.052. PMID 16378605. 
• Schratl P, Royer JF, Kostenis E et al. (2007). "The role of the prostaglandin D2 receptor, DP, in eosinophil trafficking". J. Immunol. 179 (7): 4792–9. PMID 17878378. 

External links

• "Prostanoid Receptors: DP₂". IUPHAR Database of Receptors and Ion Channels. International Union of Basic and Clinical Pharmacology. 
• GPR44 protein, human at the US National Library of Medicine Medical Subject Headings (MeSH)

This article incorporates text from the United States National Library of Medicine, which is in the public domain.