Seroatlas · Human Serome Atlas

CHRM4

Muscarinic acetylcholine receptor M4

Also known as: ACM4_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
P08173
Gene
CHRM4
Ensembl
ENSG00000180720
Chromosome
11
Canonical length
479 aa
Protein class
FDA approved drug targets, G-protein coupled receptors, Predicted membrane proteins
Subcellular location
Nucleoplasm,Golgi apparatus

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 clinical implications of this receptor are unknown; however, mouse studies link its function to adenylyl cyclase inhibition. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

479 residues, UniProt reviewed canonical sequence.

>P08173|CHRM4
     1  MANFTPVNGS SGNQSVRLVT SSSHNRYETV EMVFIATVTG SLSLVTVVGN ILVMLSIKVN
    61  RQLQTVNNYF LFSLACADLI IGAFSMNLYT VYIIKGYWPL GAVVCDLWLA LDYVVSNASV
   121  MNLLIISFDR YFCVTKPLTY PARRTTKMAG LMIAAAWVLS FVLWAPAILF WQFVVGKRTV
   181  PDNQCFIQFL SNPAVTFGTA IAAFYLPVVI MTVLYIHISL ASRSRVHKHR PEGPKEKKAK
   241  TLAFLKSPLM KQSVKKPPPG EAAREELRNG KLEEAPPPAL PPPPRPVADK DTSNESSSGS
   301  ATQNTKERPA TELSTTEATT PAMPAPPLQP RALNPASRWS KIQIVTKQTG NECVTAIEIV
   361  PATPAGMRPA ANVARKFASI ARNQVRKKRQ MAARERKVTR TIFAILLAFI LTWTPYNVMV
   421  LVNTFCQSCI PDTVWSIGYW LCYVNSTINP ACYALCNATF KKTFRHLLLC QYRNIGTAR

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against CHRM4 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)
0.43
Highest tissue expression
14 nTPM

Expression across tissuesHPA

Tissue

  • spleen: 14 nTPM
  • small intestine: 5.8 nTPM
  • cerebral cortex: 4.6 nTPM
  • testis: 3.2 nTPM
  • duodenum: 3 nTPM
  • retina: 2.9 nTPM

Single-cell type

  • goblet cells: 15 nCPM
  • late spermatids: 10 nCPM
  • late primary spermatocytes: 8 nCPM
  • cone photoreceptor cells: 6.2 nCPM
  • pancreatic islet cells: 5.8 nCPM
  • neuroendocrine cells: 3.5 nCPM

Immune cell

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

Brain region

  • basal ganglia: 44 nTPM
  • cerebral cortex: 14 nTPM
  • hippocampal formation: 11 nTPM
  • amygdala: 11 nTPM
  • thalamus: 8.4 nTPM
  • hypothalamus: 6.9 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)
0.27
gnomAD pLI
0.97
gnomAD missense Z
2.73
DepMap mean gene effect
-0.16
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

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads CHRM4 as an antibody target. Whether an autoantibody or antibody against CHRM4 could matter depends on whether native CHRM4 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

CHRM4 is annotated at the cell surface, where native CHRM4 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 CHRM4 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/CHRM4. 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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