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COX6A2 cytochrome c oxidase subunit 6A2 [ Homo sapiens (human) ]

Gene ID: 1339, updated on 17-Jun-2024


Official Symbol
COX6A2provided by HGNC
Official Full Name
cytochrome c oxidase subunit 6A2provided by HGNC
Primary source
See related
Ensembl:ENSG00000156885 MIM:602009; AllianceGenome:HGNC:2279
Gene type
protein coding
RefSeq status
Homo sapiens
Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia; Eutheria; Euarchontoglires; Primates; Haplorrhini; Catarrhini; Hominidae; Homo
Also known as
Cytochrome c oxidase (COX), the terminal enzyme of the mitochondrial respiratory chain, catalyzes the electron transfer from reduced cytochrome c to oxygen. It is a heteromeric complex consisting of 3 catalytic subunits encoded by mitochondrial genes and multiple structural subunits encoded by nuclear genes. The mitochondrially-encoded subunits function in electron transfer, and the nuclear-encoded subunits may be involved in the regulation and assembly of the complex. This nuclear gene encodes polypeptide 2 (heart/muscle isoform) of subunit VIa, and polypeptide 2 is present only in striated muscles. Polypeptide 1 (liver isoform) of subunit VIa is encoded by a different gene, and is found in all non-muscle tissues. These two polypeptides share 66% amino acid sequence identity. [provided by RefSeq, Jul 2008]
Biased expression in heart (RPKM 177.9), prostate (RPKM 30.1) and 1 other tissue See more
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Genomic context

See COX6A2 in Genome Data Viewer
Exon count:
Annotation release Status Assembly Chr Location
RS_2023_10 current GRCh38.p14 (GCF_000001405.40) 16 NC_000016.10 (31427731..31428360, complement)
RS_2023_10 current T2T-CHM13v2.0 (GCF_009914755.1) 16 NC_060940.1 (31815129..31815775, complement)
105.20220307 previous assembly GRCh37.p13 (GCF_000001405.25) 16 NC_000016.9 (31439052..31439681, complement)

Chromosome 16 - NC_000016.10Genomic Context describing neighboring genes Neighboring gene integrin subunit alpha X pseudogene Neighboring gene integrin subunit alpha X Neighboring gene NANOG-H3K27ac hESC enhancer GRCh37_chr16:31379880-31380486 Neighboring gene H3K4me1 hESC enhancer GRCh37_chr16:31393428-31393928 Neighboring gene H3K4me1 hESC enhancer GRCh37_chr16:31393929-31394429 Neighboring gene integrin subunit alpha D Neighboring gene H3K4me1 hESC enhancer GRCh37_chr16:31446802-31447302 Neighboring gene ReSE screen-validated silencer GRCh37_chr16:31447884-31448054 Neighboring gene H3K27ac-H3K4me1 hESC enhancer GRCh37_chr16:31453737-31454532 Neighboring gene zinc finger protein 843 Neighboring gene Sharpr-MPRA regulatory region 15326 Neighboring gene H3K27ac-H3K4me1 hESC enhancer GRCh37_chr16:31464004-31464776 Neighboring gene H3K27ac-H3K4me1 hESC enhancer GRCh37_chr16:31464777-31465548 Neighboring gene H3K4me1 hESC enhancer GRCh37_chr16:31468736-31469304 Neighboring gene H3K27ac hESC enhancer GRCh37_chr16:31469952-31470492 Neighboring gene ATAC-STARR-seq lymphoblastoid active region 10764 Neighboring gene ATAC-STARR-seq lymphoblastoid silent region 7419 Neighboring gene armadillo repeat containing 5

Genomic regions, transcripts, and products


  • Project title: HPA RNA-seq normal tissues
  • Description: RNA-seq was performed of tissue samples from 95 human individuals representing 27 different tissues in order to determine tissue-specificity of all protein-coding genes
  • BioProject: PRJEB4337
  • Publication: PMID 24309898
  • Analysis date: Wed Apr 4 07:08:55 2018


GeneRIFs: Gene References Into Functions

What's a GeneRIF?

HIV-1 interactions

Protein interactions

Protein Gene Interaction Pubs
Tat tat Tat-induced mitochondrial membrane permeabilization is associated with inhibition of cytochrome c oxidase (COX) activity by Tat in disrupted mitochondria from human samples PubMed

Go to the HIV-1, Human Interaction Database

Pathways from PubChem


Products Interactant Other Gene Complex Source Pubs Description

General gene information


Gene Ontology Provided by GOA

Function Evidence Code Pubs
enables enzyme regulator activity IBA
Inferred from Biological aspect of Ancestor
more info
enables oxidoreductase activity IEA
Inferred from Electronic Annotation
more info
Process Evidence Code Pubs
involved_in generation of precursor metabolites and energy TAS
Traceable Author Statement
more info
involved_in mitochondrial electron transport, cytochrome c to oxygen IBA
Inferred from Biological aspect of Ancestor
more info
Component Evidence Code Pubs
part_of mitochondrial respiratory chain complex IV IBA
Inferred from Biological aspect of Ancestor
more info

General protein information

Preferred Names
cytochrome c oxidase subunit 6A2, mitochondrial
cytochrome c oxidase polypeptide VIa-heart
cytochrome c oxidase subunit VIA-muscle
cytochrome c oxidase subunit VIa polypeptide 2

NCBI Reference Sequences (RefSeq)

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RefSeqs maintained independently of Annotated Genomes

These reference sequences exist independently of genome builds. Explain

These reference sequences are curated independently of the genome annotation cycle, so their versions may not match the RefSeq versions in the current genome build. Identify version mismatches by comparing the version of the RefSeq in this section to the one reported in Genomic regions, transcripts, and products above.

mRNA and Protein(s)

  1. NM_005205.4NP_005196.1  cytochrome c oxidase subunit 6A2, mitochondrial precursor

    See identical proteins and their annotated locations for NP_005196.1

    Status: REVIEWED

    Source sequence(s)
    Consensus CDS
    O00761, Q02221, Q6GTW6
    ENSP00000287490.4, ENST00000287490.5
    Conserved Domains (1) summary
    Cyt_c_Oxidase_VIa; Cytochrome c oxidase subunit VIa. Cytochrome c oxidase (CcO), the terminal oxidase in the respiratory chains of eukaryotes and most bacteria, is a multi-chain transmembrane protein located in the inner membrane of mitochondria and the cell membrane of ...

RefSeqs of Annotated Genomes: GCF_000001405.40-RS_2023_10

The following sections contain reference sequences that belong to a specific genome build. Explain

Reference GRCh38.p14 Primary Assembly


  1. NC_000016.10 Reference GRCh38.p14 Primary Assembly

    31427731..31428360 complement
    GenBank, FASTA, Sequence Viewer (Graphics)

Alternate T2T-CHM13v2.0


  1. NC_060940.1 Alternate T2T-CHM13v2.0

    31815129..31815775 complement
    GenBank, FASTA, Sequence Viewer (Graphics)