Seroatlas · Human Serome Atlas

CYB5R1

NADH-cytochrome b5 reductase 1

Also known as: humb5R2, NB5R1_HUMAN, NQO3A2

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

Protein identityUniProt · HPA

UniProt accession: Q9UHQ9
Gene: CYB5R1
Ensembl: ENSG00000159348
Chromosome: 1
Canonical length: 305 aa
Protein class: Enzymes, Metabolic proteins, Predicted intracellular proteins
Subcellular location: Mitochondria,Cytosol

OverviewNCBI Gene

Predicted to enable FAD binding activity. Predicted to be involved in bicarbonate transport. Located in cytosol and mitochondrion. [provided by Alliance of Genome Resources, Jul 2025]

Canonical amino-acid sequenceUniProt

305 residues, UniProt reviewed canonical sequence.

>Q9UHQ9|CYB5R1
     1  MGIQTSPVLL ASLGVGLVTL LGLAVGSYLV RRSRRPQVTL LDPNEKYLLR LLDKTTVSHN
    61  TKRFRFALPT AHHTLGLPVG KHIYLSTRID GSLVIRPYTP VTSDEDQGYV DLVIKVYLKG
   121  VHPKFPEGGK MSQYLDSLKV GDVVEFRGPS GLLTYTGKGH FNIQPNKKSP PEPRVAKKLG
   181  MIAGGTGITP MLQLIRAILK VPEDPTQCFL LFANQTEKDI ILREDLEELQ ARYPNRFKLW
   241  FTLDHPPKDW AYSKGFVTAD MIREHLPAPG DDVLVLLCGP PPMVQLACHP NLDKLGYSQK
   301  MRFTY

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against CYB5R1 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: Cell surface
Secreted: No
Transmembrane segments: 1
Mean surface accessibility (rSASA): 0.29
Highest tissue expression: 592 nTPM

Expression across tissuesHPA

Tissue

skeletal muscle: 592 nTPM
tongue: 288 nTPM
heart muscle: 149 nTPM
epididymis: 124 nTPM
choroid plexus: 124 nTPM
skin: 119 nTPM

Single-cell type

syncytiotrophoblasts: 389 nCPM
migrating cytotrophoblasts: 348 nCPM
platelets: 305 nCPM
extravillous trophoblasts: 269 nCPM
parietal cells: 249 nCPM
myonuclei: 194 nCPM

Immune cell

classical monocyte: 57 nTPM
total PBMC: 53 nTPM
eosinophil: 47 nTPM
neutrophil: 46 nTPM
intermediate monocyte: 43 nTPM
naive CD4 T-cell: 42 nTPM

Brain region

choroid plexus: 68 nTPM
pons: 65 nTPM
midbrain: 52 nTPM
hypothalamus: 48 nTPM
medulla oblongata: 43 nTPM
white matter: 39 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): 1.36
gnomAD pLI: 0
gnomAD missense Z: 0.51
DepMap mean gene effect: -0.06
DepMap dependency class: selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 7% 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 CYB5R1 as an antibody target. Whether an autoantibody or antibody against CYB5R1 could matter depends on whether native CYB5R1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

CYB5R1 is annotated at the cell surface, where native CYB5R1 is exposed to circulating antibodies and is a prime autoantibody target that could block, deplete, or overstimulate it.

Annotation status

The present source text does not explicitly label CYB5R1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Loading the interactive Seroatlas protein explorer...