Seroatlas · Human Serome Atlas

HCAR3

Hydroxycarboxylic acid receptor 3

Also known as: GPR109B, HCA3, HCAR3_HUMAN, HM74

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

Protein identityUniProt · HPA

UniProt accession: P49019
Gene: HCAR3
Ensembl: ENSG00000255398
Chromosome: 12
Canonical length: 387 aa
Protein class: FDA approved drug targets, G-protein coupled receptors, Predicted membrane proteins
Subcellular location: Cell Junctions

OverviewNCBI Gene

Predicted to enable GTP binding activity; nicotinic acid receptor activity; and purinergic nucleotide receptor activity. Predicted to be involved in G protein-coupled receptor signaling pathway. Located in cell junction. [provided by Alliance of Genome Resources, Jul 2025]

Canonical amino-acid sequenceUniProt

387 residues, UniProt reviewed canonical sequence.

>P49019|HCAR3
     1  MNRHHLQDHF LEIDKKNCCV FRDDFIAKVL PPVLGLEFIF GLLGNGLALW IFCFHLKSWK
    61  SSRIFLFNLA VADFLLIICL PFVMDYYVRR SDWKFGDIPC RLVLFMFAMN RQGSIIFLTV
   121  VAVDRYFRVV HPHHALNKIS NWTAAIISCL LWGITVGLTV HLLKKKLLIQ NGTANVCISF
   181  SICHTFRWHE AMFLLEFFLP LGIILFCSAR IIWSLRQRQM DRHAKIKRAI TFIMVVAIVF
   241  VICFLPSVVV RIHIFWLLHT SGTQNCEVYR SVDLAFFITL SFTYMNSMLD PVVYYFSSPS
   301  FPNFFSTLIN RCLQRKITGE PDNNRSTSVE LTGDPNKTRG APEALIANSG EPWSPSYLGP
   361  TSNNHSKKGH CHQEPASLEK QLGCCIE

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against HCAR3 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): 0.35
Highest tissue expression: 26 nTPM

Expression across tissuesHPA

Tissue

bone marrow: 26 nTPM
spleen: 19 nTPM
skin: 18 nTPM
esophagus: 17 nTPM
appendix: 8.6 nTPM
lung: 8.2 nTPM

Single-cell type

esophageal apical cells: 174 nCPM
ocular epithelial cells: 169 nCPM
epididymal basal cells: 150 nCPM
urothelial cells: 148 nCPM
neutrophils: 146 nCPM
suprabasal keratinocytes: 90 nCPM

Immune cell

neutrophil: 178 nTPM
non-classical monocyte: 85 nTPM
basophil: 59 nTPM
intermediate monocyte: 17 nTPM
total PBMC: 2.9 nTPM
myeloid DC: 2.6 nTPM

Brain region

cerebral cortex: 10 nTPM
pons: 2 nTPM
choroid plexus: 0.4 nTPM
hippocampal formation: 0.3 nTPM
basal ganglia: 0.2 nTPM
thalamus: 0.2 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): 1.94
gnomAD pLI: 0
gnomAD missense Z: 0.01
DepMap mean gene effect: 0.05
DepMap dependency class: selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 4% 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 HCAR3 as an antibody target. Whether an autoantibody or antibody against HCAR3 could matter depends on whether native HCAR3 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

HCAR3 is annotated at the cell surface, where native HCAR3 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 HCAR3 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Loading the interactive Seroatlas protein explorer...