Seroatlas · Human Serome Atlas

CHRM3

Muscarinic acetylcholine receptor M3

Also known as: ACM3_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
P20309
Gene
CHRM3
Ensembl
ENSG00000133019
Chromosome
1
Canonical length
590 aa
Protein class
Disease related genes, FDA approved drug targets, G-protein coupled receptors, Human disease related genes, Predicted membrane proteins
Subcellular location
Plasma membrane
Quaternary structure
Homodimer

OverviewNCBI Gene

The muscarinic cholinergic receptors belong to a larger family of G protein-coupled receptors. The functional diversity of these receptors is defined by the binding of acetylcholine and includes cellular responses such as adenylate cyclase inhibition, phosphoinositide degeneration, and potassium channel mediation. Muscarinic receptors influence many effects of acetylcholine in the central and peripheral nervous system. The muscarinic cholinergic receptor 3 controls smooth muscle contraction and its stimulation causes secretion of glandular tissue. Alternative promoter use and alternative splicing results in multiple transcript variants that have different tissue specificities. [provided by RefSeq, Dec 2016]

Canonical amino-acid sequenceUniProt

590 residues, UniProt reviewed canonical sequence.

>P20309|CHRM3
     1  MTLHNNSTTS PLFPNISSSW IHSPSDAGLP PGTVTHFGSY NVSRAAGNFS SPDGTTDDPL
    61  GGHTVWQVVF IAFLTGILAL VTIIGNILVI VSFKVNKQLK TVNNYFLLSL ACADLIIGVI
   121  SMNLFTTYII MNRWALGNLA CDLWLAIDYV ASNASVMNLL VISFDRYFSI TRPLTYRAKR
   181  TTKRAGVMIG LAWVISFVLW APAILFWQYF VGKRTVPPGE CFIQFLSEPT ITFGTAIAAF
   241  YMPVTIMTIL YWRIYKETEK RTKELAGLQA SGTEAETENF VHPTGSSRSC SSYELQQQSM
   301  KRSNRRKYGR CHFWFTTKSW KPSSEQMDQD HSSSDSWNNN DAAASLENSA SSDEEDIGSE
   361  TRAIYSIVLK LPGHSTILNS TKLPSSDNLQ VPEEELGMVD LERKADKLQA QKSVDDGGSF
   421  PKSFSKLPIQ LESAVDTAKT SDVNSSVGKS TATLPLSFKE ATLAKRFALK TRSQITKRKR
   481  MSLVKEKKAA QTLSAILLAF IITWTPYNIM VLVNTFCDSC IPKTFWNLGY WLCYINSTVN
   541  PVCYALCNKT FRTTFKMLLL CQCDKKKRRK QQYQQRQSVI FHKRAPEQAL

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against CHRM3 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)
0.47
Highest tissue expression
17 nTPM

Expression across tissuesHPA

Tissue

  • salivary gland: 17 nTPM
  • pancreas: 10 nTPM
  • cerebral cortex: 9.4 nTPM
  • urinary bladder: 7.2 nTPM
  • esophagus: 7 nTPM
  • colon: 6.4 nTPM

Single-cell type

  • salivary acinar cells: 2,061 nCPM
  • salivary myoepithelial cells: 1,306 nCPM
  • pancreatic acinar cells: 984 nCPM
  • hematopoietic stem cells: 699 nCPM
  • mucous neck cells: 597 nCPM
  • lacrimal acinar cells: 585 nCPM

Immune cell

  • naive CD4 T-cell: 0.3 nTPM
  • intermediate monocyte: 0.2 nTPM
  • MAIT T-cell: 0.1 nTPM
  • naive CD8 T-cell: 0.1 nTPM
  • non-classical monocyte: 0.1 nTPM
  • basophil: 0 nTPM

Brain region

  • cerebral cortex: 62 nTPM
  • white matter: 43 nTPM
  • basal ganglia: 41 nTPM
  • thalamus: 40 nTPM
  • amygdala: 34 nTPM
  • pons: 23 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about CHRM3.

Disease | AllUniProt

Conditions CHRM3 is implicated in, by any mechanism.

Disease | GeneticClinVar

3 pathogenic / likely-pathogenic of 153 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

Disease | ImmuneIEDB

Conditions an epitope on CHRM3 was assayed in.

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)
0.25
gnomAD pLI
0.99
gnomAD missense Z
1.96
DepMap mean gene effect
0.1
DepMap dependency class
none

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 7% 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 CHRM3 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 CHRM3 as an antibody target. Whether an autoantibody or antibody against CHRM3 could matter depends on whether native CHRM3 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

CHRM3 is annotated at the cell surface, where native CHRM3 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 CHRM3 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/CHRM3. 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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