Seroatlas · Human Serome Atlas

COA4

Cytochrome c oxidase assembly factor 4 homolog, mitochondrial

Also known as: CHCHD8, CMC3, COA4_HUMAN, E2IG2

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

Protein identityUniProt · HPA

UniProt accession
Q9NYJ1
Gene
COA4
Ensembl
ENSG00000181924
Chromosome
11
Canonical length
87 aa
Protein class
Predicted intracellular proteins
Subcellular location
Nucleoplasm,Nucleoli fibrillar center,Mitochondria

OverviewNCBI Gene

Predicted to be involved in mitochondrial cytochrome c oxidase assembly. Located in mitochondrion. [provided by Alliance of Genome Resources, Jul 2025]

Canonical amino-acid sequenceUniProt

87 residues, UniProt reviewed canonical sequence.

>Q9NYJ1|COA4
     1  MSTSVPQGHT WTQRVKKDDE EEDPLDQLIS RSGCAASHFA VQECMAQHQD WRQCQPQVQA
    61  FKDCMSEQQA RRQEELQRRQ EQAGAHH

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against COA4 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)
0.49
Highest tissue expression
110 nTPM

Expression across tissuesHPA

Tissue

  • liver: 110 nTPM
  • adrenal gland: 107 nTPM
  • kidney: 91 nTPM
  • skeletal muscle: 82 nTPM
  • heart muscle: 67 nTPM
  • choroid plexus: 59 nTPM

Single-cell type

  • gastric progenitor cells: 262 nCPM
  • esophageal suprabasal cells: 251 nCPM
  • hepatocytes: 210 nCPM
  • esophageal basal cells: 205 nCPM
  • cytotrophoblasts: 203 nCPM
  • migrating cytotrophoblasts: 181 nCPM

Immune cell

  • plasmacytoid DC: 80 nTPM
  • myeloid DC: 61 nTPM
  • memory B-cell: 58 nTPM
  • intermediate monocyte: 52 nTPM
  • non-classical monocyte: 52 nTPM
  • classical monocyte: 50 nTPM

Brain region

  • white matter: 52 nTPM
  • basal ganglia: 44 nTPM
  • cerebellum: 43 nTPM
  • medulla oblongata: 43 nTPM
  • thalamus: 42 nTPM
  • spinal cord: 41 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)
1.48
gnomAD pLI
0.21
gnomAD missense Z
0.29
DepMap mean gene effect
-0.1
DepMap dependency class
selective

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

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads COA4 as an antibody target. Whether an autoantibody or antibody against COA4 could matter depends on whether native COA4 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

COA4 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 COA4 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/COA4. 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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