Seroatlas · Human Serome Atlas

ARPC4

Actin-related protein 2/3 complex subunit 4

Also known as: ARC20, ARPC4_HUMAN, p20-Arc

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

Protein identityUniProt · HPA

UniProt accession
P59998
Gene
ARPC4
Ensembl
ENSG00000241553
Chromosome
3
Canonical length
168 aa
Protein class
Plasma proteins, Predicted intracellular proteins

OverviewNCBI Gene

This gene encodes one of seven subunits of the human Arp2/3 protein complex. This complex controls actin polymerization in cells and has been conserved throughout eukaryotic evolution. This gene encodes the p20 subunit, which is necessary for actin nucleation and high-affinity binding to F-actin. Alternative splicing results in multiple transcript variants. Naturally occurring read-through transcription exists between this gene and the downstream tubulin tyrosine ligase-like family, member 3 (TTLL3), which results in the production of a fusion protein. [provided by RefSeq, Nov 2010]

Canonical amino-acid sequenceUniProt

168 residues, UniProt reviewed canonical sequence.

>P59998|ARPC4
     1  MTATLRPYLS AVRATLQAAL CLENFSSQVV ERHNKPEVEV RSSKELLLQP VTISRNEKEK
    61  VLIEGSINSV RVSIAVKQAD EIEKILCHKF MRFMMMRAEN FFILRRKPVE GYDISFLITN
   121  FHTEQMYKHK LVDFVIHFME EIDKEISEMK LSVNARARIV AEEFLKNF

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against ARPC4 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)
0.31
Highest tissue expression
192 nTPM

Expression across tissuesHPA

Tissue

  • tonsil: 192 nTPM
  • spleen: 165 nTPM
  • lymph node: 160 nTPM
  • esophagus: 158 nTPM
  • blood vessel: 142 nTPM
  • bone marrow: 140 nTPM

Single-cell type

  • megakaryocytes: 43 nCPM
  • microglia: 36 nCPM
  • platelets: 28 nCPM
  • cardiomyocytes: 23 nCPM
  • oligodendrocytes: 21 nCPM
  • other brain neurons: 21 nCPM

Immune cell

  • neutrophil: 642 nTPM
  • total PBMC: 481 nTPM
  • intermediate monocyte: 470 nTPM
  • non-classical monocyte: 461 nTPM
  • eosinophil: 434 nTPM
  • plasmacytoid DC: 434 nTPM

Brain region

  • hippocampal formation: 128 nTPM
  • thalamus: 121 nTPM
  • pons: 104 nTPM
  • cerebral cortex: 104 nTPM
  • white matter: 104 nTPM
  • hypothalamus: 103 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about ARPC4.

Disease | AllUniProt

Conditions ARPC4 is implicated in, by any mechanism.

  • Developmental delay, language impairment, and ocular abnormalities (DEVLO) MIM:620141

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
2.21
DepMap mean gene effect
-0.67
DepMap dependency class
common

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 5% 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 ARPC4 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 ARPC4 as an antibody target. Whether an autoantibody or antibody against ARPC4 could matter depends on whether native ARPC4 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

ARPC4 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 ARPC4 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/ARPC4. 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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