Seroatlas · Human Serome Atlas

MT-CYB

Cytochrome b

Also known as: COB, CYB_HUMAN, CYTB, MTCYB, UQCR3

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

Protein identityUniProt · HPA

UniProt accession
P00156
Gene
MT-CYB
Ensembl
ENSG00000198727
Chromosome
MT
Canonical length
380 aa
Protein class
Disease related genes, Human disease related genes, Metabolic proteins, Predicted membrane proteins
Subcellular location
Mitochondria

OverviewNCBI Gene

Predicted to enable metal ion binding activity. Predicted to contribute to ubiquinol-cytochrome-c reductase activity. Predicted to be involved in mitochondrial electron transport, ubiquinol to cytochrome c. Located in mitochondrial inner membrane. Implicated in ovarian carcinoma and urinary bladder cancer. [provided by Alliance of Genome Resources, Apr 2025]

Canonical amino-acid sequenceUniProt

380 residues, UniProt reviewed canonical sequence.

>P00156|MT-CYB
     1  MTPMRKTNPL MKLINHSFID LPTPSNISAW WNFGSLLGAC LILQITTGLF LAMHYSPDAS
    61  TAFSSIAHIT RDVNYGWIIR YLHANGASMF FICLFLHIGR GLYYGSFLYS ETWNIGIILL
   121  LATMATAFMG YVLPWGQMSF WGATVITNLL SAIPYIGTDL VQWIWGGYSV DSPTLTRFFT
   181  FHFILPFIIA ALATLHLLFL HETGSNNPLG ITSHSDKITF HPYYTIKDAL GLLLFLLSLM
   241  TLTLFSPDLL GDPDNYTLAN PLNTPPHIKP EWYFLFAYTI LRSVPNKLGG VLALLLSILI
   301  LAMIPILHMS KQQSMMFRPL SQSLYWLLAA DLLILTWIGG QPVSYPFTII GQVASVLYFT
   361  TILILMPTIS LIENKMLKWA

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against MT-CYB 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
8
Mean surface accessibility (rSASA)
0.26
Highest tissue expression
131,222 nTPM

Expression across tissuesHPA

Tissue

  • heart muscle: 131,222 nTPM
  • basal ganglia: 74,666 nTPM
  • tongue: 59,499 nTPM
  • kidney: 59,041 nTPM
  • liver: 57,549 nTPM
  • hippocampal formation: 51,888 nTPM

Single-cell type

  • retinal bipolar cells: 27,395 nCPM
  • pancreatic acinar cells: 24,886 nCPM
  • enterocytes: 23,189 nCPM
  • urothelial cells: 18,582 nCPM
  • hepatocytes: 17,796 nCPM
  • colonocytes: 17,044 nCPM

Immune cell

  • basophil: 8,872 nTPM
  • eosinophil: 4,819 nTPM
  • classical monocyte: 3,751 nTPM
  • naive B-cell: 3,043 nTPM
  • memory B-cell: 2,816 nTPM
  • naive CD8 T-cell: 2,790 nTPM

Brain region

  • choroid plexus: 41,364 nTPM
  • medulla oblongata: 37,143 nTPM
  • cerebral cortex: 32,327 nTPM
  • pons: 30,513 nTPM
  • thalamus: 29,499 nTPM
  • basal ganglia: 27,012 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about MT-CYB.

Disease | AllUniProt

Conditions MT-CYB is implicated in, by any mechanism.

  • Cardiomyopathy, infantile histiocytoid (CMIH) MIM:500000
  • Leber hereditary optic neuropathy (LHON) MIM:535000

Disease | GeneticClinVar

5 pathogenic / likely-pathogenic of 329 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

Disease | ImmuneIEDB

Conditions an epitope on MT-CYB was assayed in.

OntologyGO

Biological processes

Molecular functions

Cellular components

Protein domainsUniProt · Pfam · InterPro

  • Cytochrome b/b6, N-terminal domain
  • Cytochrome b/b6, C-terminal
  • Di-haem cytochrome, transmembrane
  • Cytochrome b/b6-like domain superfamily
  • Cytochrome b
  • Cytochrome b/b6, C-terminal domain superfamily
  • Cytochrome b/b6, N-terminal domain, eukaryotic/bacterial
  • Cytochrome b/b6, C-terminal domain, eukaryotic/bacterial
  • Cytochrome b(C-terminal)/b6/petD
  • Cytochrome b/b6/petB

KeywordsUniProt

InteractionsUniProt · HPA

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

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

Canonical record: https://seroatlas.com/gene/MT-CYB. 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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