Seroatlas · Human Serome Atlas

HTR2A

5-hydroxytryptamine receptor 2A

Also known as: 5-HT2A, 5HT2A_HUMAN, HTR2

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

Protein identityUniProt · HPA

UniProt accession
P28223
Gene
HTR2A
Ensembl
ENSG00000102468
Chromosome
13
Canonical length
471 aa
Protein class
FDA approved drug targets, G-protein coupled receptors, Human disease related genes, Predicted membrane proteins, Transporters

OverviewNCBI Gene

This gene encodes one of the receptors for serotonin, a neurotransmitter with many roles. Mutations in this gene are associated with susceptibility to schizophrenia and obsessive-compulsive disorder, and are also associated with response to the antidepressant citalopram in patients with major depressive disorder (MDD). MDD patients who also have a mutation in intron 2 of this gene show a significantly reduced response to citalopram as this antidepressant downregulates expression of this gene. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Sep 2009]

Canonical amino-acid sequenceUniProt

471 residues, UniProt reviewed canonical sequence.

>P28223|HTR2A
     1  MDILCEENTS LSSTTNSLMQ LNDDTRLYSN DFNSGEANTS DAFNWTVDSE NRTNLSCEGC
    61  LSPSCLSLLH LQEKNWSALL TAVVIILTIA GNILVIMAVS LEKKLQNATN YFLMSLAIAD
   121  MLLGFLVMPV SMLTILYGYR WPLPSKLCAV WIYLDVLFST ASIMHLCAIS LDRYVAIQNP
   181  IHHSRFNSRT KAFLKIIAVW TISVGISMPI PVFGLQDDSK VFKEGSCLLA DDNFVLIGSF
   241  VSFFIPLTIM VITYFLTIKS LQKEATLCVS DLGTRAKLAS FSFLPQSSLS SEKLFQRSIH
   301  REPGSYTGRR TMQSISNEQK ACKVLGIVFF LFVVMWCPFF ITNIMAVICK ESCNEDVIGA
   361  LLNVFVWIGY LSSAVNPLVY TLFNKTYRSA FSRYIQCQYK ENKKPLQLIL VNTIPALAYK
   421  SSQLQMGQKK NSKQDAKTTD NDCSMVALGK QHSEEASKDN SDGVNEKVSC V

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against HTR2A 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)
0.41
Highest tissue expression
18 nTPM

Expression across tissuesHPA

Tissue

  • cerebral cortex: 18 nTPM
  • blood vessel: 5.4 nTPM
  • amygdala: 3.5 nTPM
  • hypothalamus: 3.4 nTPM
  • choroid plexus: 3.2 nTPM
  • hippocampal formation: 2.7 nTPM

Single-cell type

  • choroid plexus epithelial cells: 70 nCPM
  • brain excitatory neurons: 46 nCPM
  • brain inhibitory neurons: 35 nCPM
  • other brain neurons: 28 nCPM
  • megakaryocytes: 25 nCPM
  • endometrial stromal cells: 12 nCPM

Immune cell

  • total PBMC: 0.2 nTPM
  • neutrophil: 0.1 nTPM
  • plasmacytoid DC: 0.1 nTPM
  • basophil: 0 nTPM
  • classical monocyte: 0 nTPM
  • eosinophil: 0 nTPM

Brain region

  • cerebral cortex: 40 nTPM
  • hypothalamus: 23 nTPM
  • basal ganglia: 23 nTPM
  • white matter: 19 nTPM
  • choroid plexus: 18 nTPM
  • pons: 12 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)
0.52
gnomAD pLI
0.51
gnomAD missense Z
1.75
DepMap mean gene effect
0.02
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

InteractionsUniProt · HPA

Protein binding partners of HTR2A 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 HTR2A as an antibody target. Whether an autoantibody or antibody against HTR2A could matter depends on whether native HTR2A is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

HTR2A is annotated at the cell surface, where native HTR2A 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 HTR2A as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/HTR2A. 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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