Seroatlas · Human Serome Atlas

FFAR4

Free fatty acid receptor 4

Also known as: FFAR4_HUMAN, GPR120, GPR129, O3FAR1, PGR4

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

Protein identityUniProt · HPA

UniProt accession
Q5NUL3
Gene
FFAR4
Ensembl
ENSG00000186188
Chromosome
10
Canonical length
361 aa
Protein class
FDA approved drug targets, G-protein coupled receptors, Human disease related genes, Predicted membrane proteins, Transporters
Subcellular location
Vesicles,Plasma membrane,Basal body

OverviewNCBI Gene

This gene encodes a G protein-coupled receptor (GPR) which belongs to the rhodopsin family of GPRs. The encoded protein functions as a receptor for free fatty acids, including omega-3, and participates in suppressing anti-inflammatory responses and insulin sensitizing. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Feb 2012]

Canonical amino-acid sequenceUniProt

361 residues, UniProt reviewed canonical sequence.

>Q5NUL3|FFAR4
     1  MSPECARAAG DAPLRSLEQA NRTRFPFFSD VKGDHRLVLA AVETTVLVLI FAVSLLGNVC
    61  ALVLVARRRR RGATACLVLN LFCADLLFIS AIPLVLAVRW TEAWLLGPVA CHLLFYVMTL
   121  SGSVTILTLA AVSLERMVCI VHLQRGVRGP GRRARAVLLA LIWGYSAVAA LPLCVFFRVV
   181  PQRLPGADQE ISICTLIWPT IPGEISWDVS FVTLNFLVPG LVIVISYSKI LQITKASRKR
   241  LTVSLAYSES HQIRVSQQDF RLFRTLFLLM VSFFIMWSPI IITILLILIQ NFKQDLVIWP
   301  SLFFWVVAFT FANSALNPIL YNMTLCRNEW KKIFCCFWFP EKGAILTDTS VKRNDLSIIS
   361  G

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against FFAR4 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)
0.34
Highest tissue expression
11 nTPM

Expression across tissuesHPA

Tissue

  • rectum: 11 nTPM
  • pituitary gland: 10 nTPM
  • colon: 7.8 nTPM
  • adipose tissue: 3.8 nTPM
  • lung: 3.4 nTPM
  • cerebral cortex: 1.4 nTPM

Single-cell type

  • epicardial cells: 357 nCPM
  • adipocytes: 167 nCPM
  • goblet cells: 126 nCPM
  • somatotrophs: 112 nCPM
  • early spermatids: 66 nCPM
  • corticotrophs: 30 nCPM

Immune cell

  • myeloid DC: 0.9 nTPM
  • classical monocyte: 0.8 nTPM
  • basophil: 0.3 nTPM
  • neutrophil: 0.2 nTPM
  • total PBMC: 0.2 nTPM
  • intermediate monocyte: 0.1 nTPM

Brain region

  • hypothalamus: 7.1 nTPM
  • basal ganglia: 4.2 nTPM
  • cerebral cortex: 4.1 nTPM
  • amygdala: 3.4 nTPM
  • midbrain: 3.3 nTPM
  • white matter: 3.2 nTPM

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)
1.26
gnomAD pLI
0
gnomAD missense Z
0.63
DepMap mean gene effect
-0.15
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

InteractionsUniProt · HPA

Protein binding partners of FFAR4 in the human serome: UniProt-annotated complex subunits plus reported interactors. Each links to its own Seroatlas record.

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads FFAR4 as an antibody target. Whether an autoantibody or antibody against FFAR4 could matter depends on whether native FFAR4 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

FFAR4 is annotated at the cell surface, where native FFAR4 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 FFAR4 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/FFAR4. 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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