title: Expression and characterization of a 5-oxo-6E,8Z,11Z,14Z-eicosatetraenoic acid receptor highly expressed on human eosinophils and neutrophils.
abstract: Using a bioinformatics approach, we have isolated a novel G-protein-coupled receptor (GPCR), R527, and have demonstrated that this receptor shows no significant homology to previously deorphanized GPCRs. Quantitative reverse transcription-polymerase chain reaction analysis of the expression of GPCR R527 indicated a very high level of mRNA expression in eosinophils, with high expression also detected in neutrophils and lung macrophages. Stable cell lines were generated expressing this receptor together with the G-protein alpha-subunit G alpha(16). These cells were used to screen an agonist collection in a calcium mobilization assay and 5-oxo-6E,8Z,11Z,14Z-eicosatetraenoic acid (5-oxo-ETE) was identified as a putative ligand. 5(S)-hydroxyperoxy-6E,8Z,11Z,14Z-eicosatetraenoic acid was also shown to activate the receptor, whereas the leukotrienes LTB(4), LTC(4), LTD(4), and LTE(4) failed to elicit a response. In cAMP assays, pertussis toxin reversed the inhibitory effects of 5-oxo-ETE on cAMP production, indicating that the receptor is G alpha(i)-coupled. The GPCR R527 shows pharmacological properties similar to those of the previously described 5-oxo-ETE receptor expressed on eosinophils, neutrophils, and monocytes. These cell types show chemotactic responses to 5-oxo-ETE, and this eicosanoid has been proposed to play a key role in the inflammatory response. The molecular identification of a receptor binding 5-oxo-ETE will expand our understanding of the physiological role of this mediator and may provide new therapeutic opportunities.
authors.affiliation: Novartis Horsham Research Centre, Horsham West Sussex, UK. carol.jones@pharma.novartis.com
authors.forename: Carol E
authors.initials: CE
authors.lastname: Jones
authors.forename: Suzanne
authors.initials: S
authors.lastname: Holden
authors.forename: Laurent
authors.initials: L
authors.lastname: Tenaillon
authors.forename: Umesh
authors.initials: U
authors.lastname: Bhatia
authors.forename: Klaus
authors.initials: K
authors.lastname: Seuwen
authors.forename: Pamela
authors.initials: P
authors.lastname: Tranter
authors.forename: Jonathan
authors.initials: J
authors.lastname: Turner
authors.forename: Rachel
authors.initials: R
authors.lastname: Kettle
authors.forename: Rochdi
authors.initials: R
authors.lastname: Bouhelal
authors.forename: Steven
authors.initials: S
authors.lastname: Charlton
authors.forename: N R
authors.initials: NR
authors.lastname: Nirmala
authors.forename: Gabor
authors.initials: G
authors.lastname: Jarai
authors.forename: Peter
authors.initials: P
authors.lastname: Finan
mesh_terms: D000595:Amino Acid Sequence; D001095:Arachidonic Acids / Q000378:metabolism*; D001483:Base Sequence; D002460:Cell Line; D002478:Cells, Cultured; D003001:Cloning, Molecular; D000242:Cyclic AMP / Q000378:metabolism; D004804:Eosinophils / Q000378:metabolism*; D015870:Gene Expression; D006801:Humans; D008024:Ligands; D008969:Molecular Sequence Data; D009504:Neutrophils / Q000378:metabolism*; D011956:Receptors, Cell Surface / Q000235:genetics*; D043562:Receptors, G-Protein-Coupled; D017386:Sequence Homology, Amino Acid
chemical_list: D001095:Arachidonic Acids; C472320:G-protein-coupled receptor R527, human; D008024:Ligands; D011956:Receptors, Cell Surface; D043562:Receptors, G-Protein-Coupled; C080828:5-oxo-6,8,11,14-eicosatetraenoic acid; D000242:Cyclic AMP