Seroatlas · Human Serome Atlas

CYB5R2

NADH-cytochrome b5 reductase 2

Also known as: NB5R2_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q6BCY4
Gene
CYB5R2
Ensembl
ENSG00000166394
Chromosome
11
Canonical length
276 aa
Protein class
Enzymes, Metabolic proteins, Predicted intracellular proteins, Predicted membrane proteins
Subcellular location
Nucleoplasm,Golgi apparatus

OverviewNCBI Gene

The protein encoded by this gene belongs to the flavoprotein pyridine nucleotide cytochrome reductase family of proteins. Cytochrome b-type NAD(P)H oxidoreductases are implicated in many processes including cholesterol biosynthesis, fatty acid desaturation and elongation, and respiratory burst in neutrophils and macrophages. Cytochrome b5 reductases have soluble and membrane-bound forms that are the product of alternative splicing. In animal cells, the membrane-bound form binds to the endoplasmic reticulum, where it is a member of a fatty acid desaturation complex. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Nov 2014]

Canonical amino-acid sequenceUniProt

276 residues, UniProt reviewed canonical sequence.

>Q6BCY4|CYB5R2
     1  MNSRRREPIT LQDPEAKYPL PLIEKEKISH NTRRFRFGLP SPDHVLGLPV GNYVQLLAKI
    61  DNELVVRAYT PVSSDDDRGF VDLIIKIYFK NVHPQYPEGG KMTQYLENMK IGETIFFRGP
   121  RGRLFYHGPG NLGIRPDQTS EPKKTLADHL GMIAGGTGIT PMLQLIRHIT KDPSDRTRMS
   181  LIFANQTEED ILVRKELEEI ARTHPDQFNL WYTLDRPPIG WKYSSGFVTA DMIKEHLPPP
   241  AKSTLILVCG PPPLIQTAAH PNLEKLGYTQ DMIFTY

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against CYB5R2 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
0
Mean surface accessibility (rSASA)
0.27
Highest tissue expression
129 nTPM

Expression across tissuesHPA

Tissue

  • retina: 129 nTPM
  • testis: 127 nTPM
  • skin: 49 nTPM
  • salivary gland: 35 nTPM
  • spinal cord: 34 nTPM
  • hippocampal formation: 28 nTPM

Single-cell type

  • late spermatids: 1,010 nCPM
  • late primary spermatocytes: 298 nCPM
  • early spermatids: 248 nCPM
  • rod photoreceptor cells: 71 nCPM
  • schwann cells: 62 nCPM
  • esophageal apical cells: 40 nCPM

Immune cell

  • memory B-cell: 11 nTPM
  • eosinophil: 6.1 nTPM
  • naive B-cell: 2.8 nTPM
  • classical monocyte: 0.9 nTPM
  • total PBMC: 0.6 nTPM
  • intermediate monocyte: 0.5 nTPM

Brain region

  • white matter: 38 nTPM
  • basal ganglia: 28 nTPM
  • midbrain: 27 nTPM
  • thalamus: 25 nTPM
  • cerebral cortex: 25 nTPM
  • medulla oblongata: 21 nTPM

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)
1.57
gnomAD pLI
0
gnomAD missense Z
-1.28
DepMap mean gene effect
0.05
DepMap dependency class
none

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

Biological processes

Molecular functions

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads CYB5R2 as an antibody target. Whether an autoantibody or antibody against CYB5R2 could matter depends on whether native CYB5R2 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

CYB5R2 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 CYB5R2 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/CYB5R2. 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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