Seroatlas · Human Serome Atlas

COA3

Cytochrome c oxidase assembly factor 3 homolog, mitochondrial

Also known as: CCDC56, COA3_HUMAN, COX25, hCOA3, HSPC009, MITRAC12

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

Protein identityUniProt · HPA

UniProt accession
Q9Y2R0
Gene
COA3
Ensembl
ENSG00000183978
Chromosome
17
Canonical length
106 aa
Protein class
Disease related genes, Human disease related genes, Predicted membrane proteins
Subcellular location
Mitochondria

OverviewNCBI Gene

This gene encodes a member of the cytochrome c oxidase assembly factor family. Studies of a related gene in fly suggest that the encoded protein is localized to mitochondria and is essential for cytochrome c oxidase function. [provided by RefSeq, Nov 2012]

Canonical amino-acid sequenceUniProt

106 residues, UniProt reviewed canonical sequence.

>Q9Y2R0|COA3
     1  MASSGAGDPL DSKRGEAPFA QRIDPTREKL TPEQLHSMRQ AELAQWQKVL PRRRTRNIVT
    61  GLGIGALVLA IYGYTFYSIS QERFLDELED EAKAARARAL ARASGS

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against COA3 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
Other membrane
Secreted
No
Transmembrane segments
1
Mean surface accessibility (rSASA)
0.56
Highest tissue expression
266 nTPM

Expression across tissuesHPA

Tissue

  • kidney: 266 nTPM
  • pancreas: 163 nTPM
  • epididymis: 163 nTPM
  • liver: 152 nTPM
  • amygdala: 133 nTPM
  • cerebral cortex: 127 nTPM

Single-cell type

  • esophageal suprabasal cells: 707 nCPM
  • parietal cells: 654 nCPM
  • esophageal apical cells: 568 nCPM
  • hepatocytes: 414 nCPM
  • esophageal basal cells: 386 nCPM
  • epididymal principal cells: 383 nCPM

Immune cell

  • total PBMC: 246 nTPM
  • memory B-cell: 220 nTPM
  • classical monocyte: 210 nTPM
  • intermediate monocyte: 208 nTPM
  • basophil: 208 nTPM
  • T-reg: 192 nTPM

Brain region

  • cerebellum: 61 nTPM
  • pons: 58 nTPM
  • thalamus: 57 nTPM
  • choroid plexus: 56 nTPM
  • midbrain: 56 nTPM
  • spinal cord: 56 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about COA3.

Disease | AllUniProt

Conditions COA3 is implicated in, by any mechanism.

  • Mitochondrial complex IV deficiency, nuclear type 14 (MC4DN14) MIM:619058

Disease | ImmuneIEDB

Conditions an epitope on COA3 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)
1.53
gnomAD pLI
0.06
gnomAD missense Z
-0.19
DepMap mean gene effect
-0.29
DepMap dependency class
selective

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

Cellular components

Protein domainsUniProt · Pfam · InterPro

  • Cytochrome c oxidase assembly factor 3, mitochondrial, coiled-coil domain
  • Cytochrome c oxidase assembly factor 3, mitochondrial
  • Cytochrome c oxidase assembly factor 3

KeywordsUniProt

InteractionsUniProt · HPA

Protein binding partners of COA3 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 COA3 as an antibody target. Whether an autoantibody or antibody against COA3 could matter depends on whether native COA3 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

COA3 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 COA3 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/COA3. 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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