Seroatlas · Human Serome Atlas

HTR3B

5-hydroxytryptamine receptor 3B

Also known as: 5-HT3B, 5HT3B_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
O95264
Gene
HTR3B
Ensembl
ENSG00000149305
Chromosome
11
Canonical length
441 aa
Protein class
FDA approved drug targets, Predicted intracellular proteins, Predicted membrane proteins, Transporters

OverviewNCBI Gene

The product of this gene belongs to the ligand-gated ion channel receptor superfamily. This gene encodes subunit B of the type 3 receptor for 5-hydroxytryptamine (serotonin), a biogenic hormone that functions as a neurotransmitter, a hormone, and a mitogen. This receptor causes fast, depolarizing responses in neurons after activation. It is not functional as a homomeric complex, but a pentaheteromeric complex with subunit A (HTR3A) displays the full functional features of this receptor. [provided by RefSeq, Aug 2011]

Canonical amino-acid sequenceUniProt

441 residues, UniProt reviewed canonical sequence.

>O95264|HTR3B
     1  MLSSVMAPLW ACILVAAGIL ATDTHHPQDS ALYHLSKQLL QKYHKEVRPV YNWTKATTVY
    61  LDLFVHAILD VDAENQILKT SVWYQEVWND EFLSWNSSMF DEIREISLPL SAIWAPDIII
   121  NEFVDIERYP DLPYVYVNSS GTIENYKPIQ VVSACSLETY AFPFDVQNCS LTFKSILHTV
   181  EDVDLAFLRS PEDIQHDKKA FLNDSEWELL SVSSTYSILQ SSAGGFAQIQ FNVVMRRHPL
   241  VYVVSLLIPS IFLMLVDLGS FYLPPNCRAR IVFKTSVLVG YTVFRVNMSN QVPRSVGSTP
   301  LIGHFFTICM AFLVLSLAKS IVLVKFLHDE QRGGQEQPFL CLRGDTDADR PRVEPRAQRA
   361  VVTESSLYGE HLAQPGTLKE VWSQLQSISN YLQTQDQTDQ QEAEWLVLLS RFDRLLFQSY
   421  LFMLGIYTIT LCSLWALWGG V

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against HTR3B 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
4
Mean surface accessibility (rSASA)
0.36
Highest tissue expression
3.9 nTPM

Expression across tissuesHPA

Tissue

  • cerebral cortex: 3.9 nTPM
  • esophagus: 0.5 nTPM
  • amygdala: 0.4 nTPM
  • bone marrow: 0.4 nTPM
  • testis: 0.4 nTPM
  • hippocampal formation: 0.3 nTPM

Single-cell type

  • renal collecting duct intercalated cells: 10 nCPM
  • esophageal apical cells: 9.2 nCPM
  • brain excitatory neurons: 3.2 nCPM
  • platelets: 2.8 nCPM
  • sertoli cells: 2.2 nCPM
  • epididymal clear cells: 2 nCPM

Immune cell

  • basophil: 1 nTPM
  • neutrophil: 0.9 nTPM
  • NK-cell: 0.4 nTPM
  • naive B-cell: 0.3 nTPM
  • plasmacytoid DC: 0.3 nTPM
  • classical monocyte: 0.2 nTPM

Brain region

  • cerebral cortex: 13 nTPM
  • white matter: 7.9 nTPM
  • basal ganglia: 7.4 nTPM
  • amygdala: 5.4 nTPM
  • cerebellum: 5.2 nTPM
  • choroid plexus: 5 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)
0.96
gnomAD pLI
0
gnomAD missense Z
0.03
DepMap mean gene effect
0.14
DepMap dependency class
none

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 HTR3B as an antibody target. Whether an autoantibody or antibody against HTR3B could matter depends on whether native HTR3B is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

HTR3B is annotated at the cell surface, where native HTR3B 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 HTR3B as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/HTR3B. 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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