Seroatlas · Human Serome Atlas

CHRNB3

Neuronal acetylcholine receptor subunit beta-3

Also known as: ACHB3_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q05901
Gene
CHRNB3
Ensembl
ENSG00000147432
Chromosome
8
Canonical length
458 aa
Protein class
FDA approved drug targets, Predicted intracellular proteins, Predicted membrane proteins

OverviewNCBI Gene

The nicotinic acetylcholine receptors (nAChRs) are members of a superfamily of ligand-gated ion channels that mediate fast signal transmission at synapses. The nAChRs are (hetero)pentamers composed of homologous subunits. The subunits that make up the muscle and neuronal forms of nAChRs are encoded by separate genes and have different primary structure. There are several subtypes of neuronal nAChRs that vary based on which homologous subunits are arranged around the central channel. They are classified as alpha-subunits if, like muscle alpha-1 (MIM 100690), they have a pair of adjacent cysteines as part of the presumed acetylcholine binding site. Subunits lacking these cysteine residues are classified as beta-subunits (Groot Kormelink and Luyten, 1997 [PubMed 9009220]). Elliott et al. (1996) [PubMed 8906617] stated that the proposed structure for each subunit is a conserved N-terminal extracellular domain followed by 3 conserved transmembrane domains, a variable cytoplasmic loop, a fourth conserved transmembrane domain, and a short C-terminal extracellular region.[supplied by OMIM, Apr 2010]

Canonical amino-acid sequenceUniProt

458 residues, UniProt reviewed canonical sequence.

>Q05901|CHRNB3
     1  MLPDFMLVLI VLGIPSSATT GFNSIAENED ALLRHLFQGY QKWVRPVLHS NDTIKVYFGL
    61  KISQLVDVDE KNQLMTTNVW LKQEWTDHKL RWNPDDYGGI HSIKVPSESL WLPDIVLFEN
   121  ADGRFEGSLM TKVIVKSNGT VVWTPPASYK SSCTMDVTFF PFDRQNCSMK FGSWTYDGTM
   181  VDLILINENV DRKDFFDNGE WEILNAKGMK GNRRDGVYSY PFITYSFVLR RLPLFYTLFL
   241  IIPCLGLSFL TVLVFYLPSD EGEKLSLSTS VLVSLTVFLL VIEEIIPSSS KVIPLIGEYL
   301  LFIMIFVTLS IIVTVFVINV HHRSSSTYHP MAPWVKRLFL QKLPKLLCMK DHVDRYSSPE
   361  KEESQPVVKG KVLEKKKQKQ LSDGEKVLVA FLEKAADSIR YISRHVKKEH FISQVVQDWK
   421  FVAQVLDRIF LWLFLIVSVT GSVLIFTPAL KMWLHSYH

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against CHRNB3 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)
0.34
Highest tissue expression
3.5 nTPM

Expression across tissuesHPA

Tissue

  • retina: 3.5 nTPM
  • midbrain: 2.5 nTPM
  • pancreas: 1.7 nTPM
  • cerebellum: 1.3 nTPM
  • testis: 1.2 nTPM
  • cerebral cortex: 0.3 nTPM

Single-cell type

  • retinal ganglion cells: 70 nCPM
  • retinal amacrine cells: 30 nCPM
  • epicardial cells: 14 nCPM
  • brain excitatory neurons: 7.7 nCPM
  • other brain neurons: 5.4 nCPM
  • late primary spermatocytes: 4.7 nCPM

Immune cell

  • naive CD4 T-cell: 0.2 nTPM
  • T-reg: 0.2 nTPM
  • basophil: 0 nTPM
  • classical monocyte: 0 nTPM
  • eosinophil: 0 nTPM
  • gdT-cell: 0 nTPM

Brain region

  • cerebellum: 26 nTPM
  • midbrain: 22 nTPM
  • hypothalamus: 5.4 nTPM
  • cerebral cortex: 4.4 nTPM
  • white matter: 1.7 nTPM
  • thalamus: 1.4 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
0.84
DepMap mean gene effect
-0.01
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 2% 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 CHRNB3 as an antibody target. Whether an autoantibody or antibody against CHRNB3 could matter depends on whether native CHRNB3 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

CHRNB3 is annotated at the cell surface, where native CHRNB3 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 CHRNB3 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/CHRNB3. 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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