Seroatlas · Human Serome Atlas

COX4I1

Cytochrome c oxidase subunit 4 isoform 1, mitochondrial

Also known as: COX4, COX4-1, COX41_HUMAN, COXIV, COXIV-1

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

Protein identityUniProt · HPA

UniProt accession
P13073
Gene
COX4I1
Ensembl
ENSG00000131143
Chromosome
16
Canonical length
169 aa
Protein class
Disease related genes, Human disease related genes, Metabolic proteins, Potential drug targets, Predicted intracellular proteins, Predicted membrane proteins, Transporters
Subcellular location
Mitochondria

OverviewNCBI Gene

Cytochrome c oxidase (COX) is the terminal enzyme of the mitochondrial respiratory chain. It is a multi-subunit enzyme complex that couples the transfer of electrons from cytochrome c to molecular oxygen and contributes to a proton electrochemical gradient across the inner mitochondrial membrane. The complex consists of 13 mitochondrial- and nuclear-encoded subunits. The mitochondrially-encoded subunits perform the electron transfer and proton pumping activities. The functions of the nuclear-encoded subunits are unknown but they may play a role in the regulation and assembly of the complex. This gene encodes the nuclear-encoded subunit IV isoform 1 of the human mitochondrial respiratory chain enzyme. It is located at the 3' of the NOC4 (neighbor of COX4) gene in a head-to-head orientation, and shares a promoter with it. Pseudogenes related to this gene are located on chromosomes 13 and 14. Alternative splicing results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Jan 2016]

Canonical amino-acid sequenceUniProt

169 residues, UniProt reviewed canonical sequence.

>P13073|COX4I1
     1  MLATRVFSLV GKRAISTSVC VRAHESVVKS EDFSLPAYMD RRDHPLPEVA HVKHLSASQK
    61  ALKEKEKASW SSLSMDEKVE LYRIKFKESF AEMNRGSNEW KTVVGGAMFF IGFTALVIMW
   121  QKHYVYGPLP QSFDKEWVAK QTKRMLDMKV NPIQGLASKW DYEKNEWKK

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against COX4I1 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)
0.48
Highest tissue expression
1,925 nTPM

Expression across tissuesHPA

Tissue

  • tongue: 1,925 nTPM
  • heart muscle: 1,781 nTPM
  • skeletal muscle: 1,250 nTPM
  • choroid plexus: 1,082 nTPM
  • amygdala: 935 nTPM
  • midbrain: 920 nTPM

Single-cell type

  • parietal cells: 4,070 nCPM
  • enterocytes: 3,311 nCPM
  • esophageal suprabasal cells: 3,209 nCPM
  • esophageal apical cells: 2,870 nCPM
  • colonocytes: 2,801 nCPM
  • esophageal basal cells: 2,553 nCPM

Immune cell

  • total PBMC: 2,816 nTPM
  • myeloid DC: 1,483 nTPM
  • classical monocyte: 1,376 nTPM
  • memory B-cell: 1,308 nTPM
  • naive B-cell: 1,237 nTPM
  • intermediate monocyte: 1,201 nTPM

Brain region

  • thalamus: 469 nTPM
  • hypothalamus: 432 nTPM
  • pons: 425 nTPM
  • cerebral cortex: 411 nTPM
  • medulla oblongata: 405 nTPM
  • cerebellum: 403 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about COX4I1.

Disease | AllUniProt

Conditions COX4I1 is implicated in, by any mechanism.

  • Mitochondrial complex IV deficiency, nuclear type 16 (MC4DN16) MIM:619060

Disease | GeneticClinVar

2 pathogenic / likely-pathogenic of 50 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

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)
0.68
gnomAD pLI
0.39
gnomAD missense Z
-0.17
DepMap mean gene effect
-0.36
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

InteractionsUniProt · HPA

Protein binding partners of COX4I1 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 COX4I1 as an antibody target. Whether an autoantibody or antibody against COX4I1 could matter depends on whether native COX4I1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

COX4I1 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 COX4I1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/COX4I1. 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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