Seroatlas · Human Serome Atlas

HTR1B

5-hydroxytryptamine receptor 1B

Also known as: 5-HT1B, 5-HT1DB, 5HT1B_HUMAN, HTR1D2, S12

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

Protein identityUniProt · HPA

UniProt accession
P28222
Gene
HTR1B
Ensembl
ENSG00000135312
Chromosome
6
Canonical length
390 aa
Protein class
FDA approved drug targets, G-protein coupled receptors, Predicted membrane proteins, Transporters
Subcellular location
Endoplasmic reticulum,Plasma membrane
Quaternary structure
Homodimer

OverviewNCBI Gene

The protein encoded by this intronless gene is a G-protein coupled receptor for serotonin (5-hydroxytryptamine). Ligand binding activates second messengers that inhibit the activity of adenylate cyclase and manage the release of serotonin, dopamine, and acetylcholine in the brain. The encoded protein may be involved in several neuropsychiatric disorders and therefore is often a target of antidepressant and other psychotherapeutic drugs. [provided by RefSeq, Nov 2015]

Canonical amino-acid sequenceUniProt

390 residues, UniProt reviewed canonical sequence.

>P28222|HTR1B
     1  MEEPGAQCAP PPPAGSETWV PQANLSSAPS QNCSAKDYIY QDSISLPWKV LLVMLLALIT
    61  LATTLSNAFV IATVYRTRKL HTPANYLIAS LAVTDLLVSI LVMPISTMYT VTGRWTLGQV
   121  VCDFWLSSDI TCCTASILHL CVIALDRYWA ITDAVEYSAK RTPKRAAVMI ALVWVFSISI
   181  SLPPFFWRQA KAEEEVSECV VNTDHILYTV YSTVGAFYFP TLLLIALYGR IYVEARSRIL
   241  KQTPNRTGKR LTRAQLITDS PGSTSSVTSI NSRVPDVPSE SGSPVYVNQV KVRVSDALLE
   301  KKKLMAARER KATKTLGIIL GAFIVCWLPF FIISLVMPIC KDACWFHLAI FDFFTWLGYL
   361  NSLINPIIYT MSNEDFKQAF HKLIRFKCTS

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against HTR1B 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)
0.38
Highest tissue expression
7.5 nTPM

Expression across tissuesHPA

Tissue

  • blood vessel: 7.5 nTPM
  • placenta: 6.3 nTPM
  • stomach: 4.7 nTPM
  • basal ganglia: 2.6 nTPM
  • cerebral cortex: 1.7 nTPM
  • urinary bladder: 1 nTPM

Single-cell type

  • adrenal medulla cells: 11 nCPM
  • retinal ganglion cells: 3.9 nCPM
  • vascular smooth muscle cells: 3.7 nCPM
  • foveolar cells: 2.7 nCPM
  • gastric progenitor cells: 2.6 nCPM
  • mucous neck cells: 1.9 nCPM

Immune cell

  • basophil: 0.4 nTPM
  • classical monocyte: 0 nTPM
  • eosinophil: 0 nTPM
  • gdT-cell: 0 nTPM
  • intermediate monocyte: 0 nTPM
  • MAIT T-cell: 0 nTPM

Brain region

  • hypothalamus: 23 nTPM
  • basal ganglia: 16 nTPM
  • midbrain: 13 nTPM
  • cerebral cortex: 11 nTPM
  • amygdala: 7.9 nTPM
  • thalamus: 7.1 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)
0.71
gnomAD pLI
0.19
gnomAD missense Z
0.78
DepMap mean gene effect
0.03
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 HTR1B 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 HTR1B as an antibody target. Whether an autoantibody or antibody against HTR1B could matter depends on whether native HTR1B is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

HTR1B is annotated at the cell surface, where native HTR1B 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 HTR1B as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/HTR1B. 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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