Top ▲


Click here for help

Target id: 228

Nomenclature: GPR42

Family: Class A Orphans, Free fatty acid receptors

Gene and Protein Information Click here for help
class A G protein-coupled receptor: probable pseudogene
Species TM AA Chromosomal Location Gene Symbol Gene Name Reference
Human 7 346 19q13.12 GPR42 G protein-coupled receptor 42 3-4
Previous and Unofficial Names Click here for help
FFAR1L | GPR41L | FFAR3L | G protein-coupled receptor 42 (gene/pseudogene)
Database Links Click here for help
Specialist databases
GPCRdb gpr42_human (Hs), gpr42_human (Hs)
Other databases
Ensembl Gene
Entrez Gene
Human Protein Atlas
RefSeq Nucleotide
RefSeq Protein
Natural/Endogenous Ligands Click here for help
Comments: Very closely related to FFA3. Might be a pseudogene.
Agonist Comments
GPR42 is thought to have arisen as a tandem duplication of FFA3 in the human lineage and has acquired mutations since duplication that abolish its ability to respond to carboxylate ions [1].
Primary Transduction Mechanisms Click here for help
Comments:  GPR42 appears to have lost the ability to activate Gi family proteins in response to carboxylate ligands due to an amino acid change at position 174 [1].
Tissue Distribution Comments
RT-PCR detected no signal for GPR42 mRNA in samples of normal human tissues [1] .
Functional Assays Click here for help
W174R amino acid change is sufficient to restore the response of GPR42 to FFA3 agonist propionate, though at a significantly lower magnitude
Species:  Rat
Tissue:  HEK293T cells
Response measured:  Receptor response to propionate
References:  1
General Comments
Two conflicting hypotheses exist regarding GPR42: the first is that it is a pseudogene, occurring infrequently in human populations as a polymorphic insert [1]. Alternative evidence from genotyping data indicates that GPR42 may be a functional gene in a significant fraction of the population, where Arg174 is present [3]. However, the very close sequence similarity of FFA3 (formerly GPR41) and GPR42 (six nucleotide differences in the coding sequence) make this very difficult to assess. The receptor shares 98% sequence homology with free fatty acid receptor FFA3 [4]. Rodents appear to have only one ortholog of the human FFA3/GPR42 pair, suggesting duplication of the locus has occurred since divergence of primate and human lineages [2].


Show »

1. Brown AJ, Goldsworthy SM, Barnes AA, Eilert MM, Tcheang L, Daniels D, Muir AI, Wigglesworth MJ, Kinghorn I, Fraser NJ et al.. (2003) The Orphan G protein-coupled receptors GPR41 and GPR43 are activated by propionate and other short chain carboxylic acids. J Biol Chem, 278 (13): 11312-9. [PMID:12496283]

2. Brown AJ, Jupe S, Briscoe CP. (2005) A family of fatty acid binding receptors. DNA Cell Biol, 24 (1): 54-61. [PMID:15684720]

3. Liaw CW, Connolly DT. (2009) Sequence polymorphisms provide a common consensus sequence for GPR41 and GPR42. DNA Cell Biol, 28 (11): 555-60. [PMID:19630535]

4. Sawzdargo M, George SR, Nguyen T, Xu S, Kolakowski LF, O'Dowd BF. (1997) A cluster of four novel human G protein-coupled receptor genes occurring in close proximity to CD22 gene on chromosome 19q13.1. Biochem Biophys Res Commun, 239 (2): 543-7. [PMID:9344866]


Show »

How to cite this page