CYB5A

Protein identityUniProt · HPA

UniProt accession

P00167

Gene

CYB5A

Ensembl

ENSG00000166347

Chromosome

18

Canonical length

134 aa

Protein class

Disease related genes, Human disease related genes, Plasma proteins, Predicted intracellular proteins, Predicted membrane proteins

Subcellular location

Vesicles,Cytosol

OverviewNCBI Gene

The protein encoded by this gene is a membrane-bound cytochrome that reduces ferric hemoglobin (methemoglobin) to ferrous hemoglobin, which is required for stearyl-CoA-desaturase activity. Defects in this gene are a cause of type IV hereditary methemoglobinemia. Three transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jun 2010]

Canonical amino-acid sequenceUniProt

134 residues, UniProt reviewed canonical sequence.

>P00167|CYB5A
     1  MAEQSDEAVK YYTLEEIQKH NHSKSTWLIL HHKVYDLTKF LEEHPGGEEV LREQAGGDAT
    61  ENFEDVGHST DAREMSKTFI IGELHPDDRP KLNKPPETLI TTIDSSSSWW TNWVIPAISA
   121  VAVALMYRLY MAED

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against CYB5A 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)

0.43

Highest tissue expression

2,307 nTPM

Expression across tissuesHPA

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about CYB5A.

Disease | AllUniProt

Conditions CYB5A is implicated in, by any mechanism.

• Methemoglobinemia and ambiguous genitalia (METAG) MIM:250790

Disease | GeneticClinVar

3 pathogenic / likely-pathogenic of 34 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

• Methemoglobinemia type 4

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)

1.43

gnomAD pLI

0

gnomAD missense Z

-0.09

DepMap mean gene effect

0.15

DepMap dependency class

selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 4% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).

OntologyGO

Molecular functions

• enzyme binding
• heme binding
• metal ion binding

Cellular components

• cytosol
• endoplasmic reticulum membrane
• membrane
• mitochondrial outer membrane

Protein domainsUniProt · Pfam · InterPro

• Cytochrome b5-like heme/steroid binding domain
• Cytochrome b5, heme-binding site
• Cytochrome b5-like heme/steroid binding domain superfamily
• Cytochrome b5
• Cytochrome b5-like Heme/Steroid binding domain

KeywordsUniProt

• Acetylation
• Cytoplasm
• Electron transport
• Endoplasmic reticulum
• Heme
• Iron
• Membrane
• Metal-binding
• Microsome
• Transmembrane
• Transmembrane helix
• Transport

InteractionsUniProt · HPA

Protein binding partners of CYB5A in the human serome: UniProt-annotated complex subunits plus reported interactors. Each links to its own Seroatlas record.

• BCAP31
• RPN1
• RPN2
• SEC61B