Seroatlas · Human Serome Atlas

FFAR1

Free fatty acid receptor 1

Also known as: FFA1R, FFAR1_HUMAN, GPR40

Cross-references: UniProt · Ensembl · Human Protein Atlas · GeneCards · NCBI Gene

Protein identityUniProt · HPA

UniProt accession
O14842
Gene
FFAR1
Ensembl
ENSG00000126266
Chromosome
19
Canonical length
300 aa
Protein class
FDA approved drug targets, G-protein coupled receptors, Predicted membrane proteins, Transporters
Subcellular location
Plasma membrane

OverviewNCBI Gene

This gene encodes a member of the GP40 family of G protein-coupled receptors that are clustered together on chromosome 19. The encoded protein is a receptor for medium and long chain free fatty acids and may be involved in the metabolic regulation of insulin secretion. Polymorphisms in this gene may be associated with type 2 diabetes. [provided by RefSeq, Apr 2009]

Canonical amino-acid sequenceUniProt

300 residues, UniProt reviewed canonical sequence.

>O14842|FFAR1
     1  MDLPPQLSFG LYVAAFALGF PLNVLAIRGA TAHARLRLTP SLVYALNLGC SDLLLTVSLP
    61  LKAVEALASG AWPLPASLCP VFAVAHFFPL YAGGGFLAAL SAGRYLGAAF PLGYQAFRRP
   121  CYSWGVCAAI WALVLCHLGL VFGLEAPGGW LDHSNTSLGI NTPVNGSPVC LEAWDPASAG
   181  PARFSLSLLL FFLPLAITAF CYVGCLRALA RSGLTHRRKL RAAWVAGGAL LTLLLCVGPY
   241  NASNVASFLY PNLGGSWRKL GLITGAWSVV LNPLVTGYLG RGPGLKTVCA ARTQGGKSQK

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against FFAR1 can act on the native protein depends on physical access: surface and secreted proteins are reachable by circulating antibodies, intracellular proteins usually are not.

Antibody reachability
Cell surface
Secreted
No
Transmembrane segments
7
Mean surface accessibility (rSASA)
0.28
Highest tissue expression
2.9 nTPM

Expression across tissuesHPA

Tissue

  • bone marrow: 2.9 nTPM
  • ovary: 2.5 nTPM
  • pancreas: 2.4 nTPM
  • spinal cord: 2.2 nTPM
  • hippocampal formation: 1.1 nTPM
  • midbrain: 1.1 nTPM

Single-cell type

  • pancreatic islet cells: 34 nCPM
  • neuroendocrine cells: 7.1 nCPM
  • oligodendrocytes: 5.1 nCPM
  • granulosa cells: 4.1 nCPM
  • b-cells: 3.7 nCPM
  • mast cells: 3.4 nCPM

Immune cell

  • basophil: 1 nTPM
  • neutrophil: 0.4 nTPM
  • naive B-cell: 0.1 nTPM
  • plasmacytoid DC: 0.1 nTPM
  • classical monocyte: 0 nTPM
  • eosinophil: 0 nTPM

Brain region

  • white matter: 11 nTPM
  • cerebral cortex: 5.2 nTPM
  • medulla oblongata: 5 nTPM
  • basal ganglia: 4.7 nTPM
  • pons: 4.6 nTPM
  • thalamus: 4.1 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about FFAR1.

Disease | GeneticClinVar

1 pathogenic / likely-pathogenic of 49 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

Genetic constraint and essentialitygnomAD · DepMap

Does the body need this protein intact? Low LOEUF or a strong DepMap dependency means loss or blockade of the protein is likely to be felt.

gnomAD LOEUF (loss-of-function intolerance)
1.66
gnomAD pLI
0
gnomAD missense Z
0.61
DepMap mean gene effect
-0.07
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 3% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).

OntologyGO

Biological processes

Molecular functions

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads FFAR1 as an antibody target. Whether an autoantibody or antibody against FFAR1 could matter depends on whether native FFAR1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

FFAR1 is annotated at the cell surface, where native FFAR1 is exposed to circulating antibodies and is a prime autoantibody target that could block, deplete, or overstimulate it.

Annotation status

The present source text does not explicitly label FFAR1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/FFAR1. Study-independent annotations aggregated from UniProt, Human Protein Atlas, PubMed, IEDB, Pfam, InterPro, Gene Ontology, AlphaFold, gnomAD, DepMap, ClinVar, TCGA. Catalog release seroatlas-reviewed-human-uniprot-20260313.

Seroatlas is the reference for exploring autoantibody and antibody serology at the human-protein level: the autoreactome and human serome, multiplex serology (HuProt, HuScan, VirScan, PhIP-Seq).

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