Seroatlas · Human Serome Atlas

ACTG2

Actin, gamma-enteric smooth muscle

Also known as: ACTA3, ACTH_HUMAN, ACTL3, ACTSG

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

Protein identityUniProt · HPA

UniProt accession
P63267
Gene
ACTG2
Ensembl
ENSG00000163017
Chromosome
2
Canonical length
376 aa
Protein class
Disease related genes, Human disease related genes, Predicted intracellular proteins

OverviewNCBI Gene

Actins are highly conserved proteins that are involved in various types of cell motility and in the maintenance of the cytoskeleton. Three types of actins, alpha, beta and gamma, have been identified in vertebrates. Alpha actins are found in muscle tissues and are a major constituent of the contractile apparatus. The beta and gamma actins co-exist in most cell types as components of the cytoskeleton and as mediators of internal cell motility. This gene encodes actin gamma 2; a smooth muscle actin found in enteric tissues. Alternative splicing results in multiple transcript variants encoding distinct isoforms. Based on similarity to peptide cleavage of related actins, the mature protein of this gene is formed by removal of two N-terminal peptides.[provided by RefSeq, Dec 2010]

Canonical amino-acid sequenceUniProt

376 residues, UniProt reviewed canonical sequence.

>P63267|ACTG2
     1  MCEEETTALV CDNGSGLCKA GFAGDDAPRA VFPSIVGRPR HQGVMVGMGQ KDSYVGDEAQ
    61  SKRGILTLKY PIEHGIITNW DDMEKIWHHS FYNELRVAPE EHPTLLTEAP LNPKANREKM
   121  TQIMFETFNV PAMYVAIQAV LSLYASGRTT GIVLDSGDGV THNVPIYEGY ALPHAIMRLD
   181  LAGRDLTDYL MKILTERGYS FVTTAEREIV RDIKEKLCYV ALDFENEMAT AASSSSLEKS
   241  YELPDGQVIT IGNERFRCPE TLFQPSFIGM ESAGIHETTY NSIMKCDIDI RKDLYANNVL
   301  SGGTTMYPGI ADRMQKEITA LAPSTMKIKI IAPPERKYSV WIGGSILASL STFQQMWISK
   361  PEYDEAGPSI VHRKCF

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against ACTG2 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
Intracellular
Secreted
No
Transmembrane segments
0
Mean surface accessibility (rSASA)
0.24
Highest tissue expression
8,437 nTPM

Expression across tissuesHPA

Tissue

  • colon: 8,437 nTPM
  • smooth muscle: 8,033 nTPM
  • seminal vesicle: 5,866 nTPM
  • endometrium: 3,281 nTPM
  • urinary bladder: 3,167 nTPM
  • prostate: 2,135 nTPM

Single-cell type

  • smooth muscle cells: 5,914 nCPM
  • breast myoepithelial cells: 2,393 nCPM
  • salivary myoepithelial cells: 714 nCPM
  • vascular smooth muscle cells: 418 nCPM
  • hepatic stellate cells: 381 nCPM
  • decidual stromal cells: 368 nCPM

Immune cell

  • T-reg: 8.6 nTPM
  • total PBMC: 2.4 nTPM
  • memory CD4 T-cell: 0.8 nTPM
  • classical monocyte: 0.5 nTPM
  • naive CD8 T-cell: 0.5 nTPM
  • non-classical monocyte: 0.5 nTPM

Brain region

  • cerebral cortex: 7.8 nTPM
  • choroid plexus: 4.5 nTPM
  • basal ganglia: 2.7 nTPM
  • medulla oblongata: 1.6 nTPM
  • pons: 0.9 nTPM
  • thalamus: 0.9 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about ACTG2.

Disease | AllUniProt

Conditions ACTG2 is implicated in, by any mechanism.

  • Visceral myopathy 1 (VSCM1) MIM:155310
  • Megacystis-microcolon-intestinal hypoperistalsis syndrome 5 (MMIHS5) MIM:619431

Disease | GeneticClinVar

42 pathogenic / likely-pathogenic of 109 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

Disease | ImmuneIEDB

Conditions an epitope on ACTG2 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)
0.63
gnomAD pLI
0.07
gnomAD missense Z
3.35
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

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads ACTG2 as an antibody target. Whether an autoantibody or antibody against ACTG2 could matter depends on whether native ACTG2 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

ACTG2 is annotated as predominantly intracellular. Intracellular proteins are common autoantibody markers, becoming visible to the immune system after cell injury or altered processing, but are usually markers of disease rather than direct drivers.

Annotation status

The present source text does not explicitly label ACTG2 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/ACTG2. 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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