Seroatlas · Human Serome Atlas

POR

NADPH--cytochrome P450 reductase

Also known as: CYPOR, FLJ26468, NCPR_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
P16435
Gene
POR
Ensembl
ENSG00000127948
Chromosome
7
Canonical length
677 aa
Protein class
Disease related genes, Enzymes, Human disease related genes, Metabolic proteins, Plasma proteins, Potential drug targets, Predicted intracellular proteins, Predicted membrane proteins
Subcellular location
Nucleoplasm,Vesicles,Cytosol

OverviewNCBI Gene

This gene encodes an endoplasmic reticulum membrane oxidoreductase that is essential for multiple metabolic processes, including reactions catalyzed by cytochrome P450 proteins for metabolism of steroid hormones, drugs and xenobiotics. The encoded protein has a flavin adenine dinucleotide (FAD)-binding domain and a flavodoxin-like domain which bind two cofactors, FAD and FMN, that allow it to donate electrons directly from NADPH to all microsomal P450 enzymes. Mutations in this gene cause a complex set of disorders, including apparent combined P450C17 and P450C21 deficiency, amenorrhea and disordered steroidogenesis, congenital adrenal hyperplasia and Antley-Bixler syndrome, that resemble those caused by defects in steroid metabolizing enzymes such as aromatase, 21-hydroxylase, and 17 alpha-hydroxylase. [provided by RefSeq, Aug 2020]

Canonical amino-acid sequenceUniProt

677 residues, UniProt reviewed canonical sequence.

>P16435|POR
     1  MGDSHVDTSS TVSEAVAEEV SLFSMTDMIL FSLIVGLLTY WFLFRKKKEE VPEFTKIQTL
    61  TSSVRESSFV EKMKKTGRNI IVFYGSQTGT AEEFANRLSK DAHRYGMRGM SADPEEYDLA
   121  DLSSLPEIDN ALVVFCMATY GEGDPTDNAQ DFYDWLQETD VDLSGVKFAV FGLGNKTYEH
   181  FNAMGKYVDK RLEQLGAQRI FELGLGDDDG NLEEDFITWR EQFWPAVCEH FGVEATGEES
   241  SIRQYELVVH TDIDAAKVYM GEMGRLKSYE NQKPPFDAKN PFLAAVTTNR KLNQGTERHL
   301  MHLELDISDS KIRYESGDHV AVYPANDSAL VNQLGKILGA DLDVVMSLNN LDEESNKKHP
   361  FPCPTSYRTA LTYYLDITNP PRTNVLYELA QYASEPSEQE LLRKMASSSG EGKELYLSWV
   421  VEARRHILAI LQDCPSLRPP IDHLCELLPR LQARYYSIAS SSKVHPNSVH ICAVVVEYET
   481  KAGRINKGVA TNWLRAKEPA GENGGRALVP MFVRKSQFRL PFKATTPVIM VGPGTGVAPF
   541  IGFIQERAWL RQQGKEVGET LLYYGCRRSD EDYLYREELA QFHRDGALTQ LNVAFSREQS
   601  HKVYVQHLLK QDREHLWKLI EGGAHIYVCG DARNMARDVQ NTFYDIVAEL GAMEHAQAVD
   661  YIKKLMTKGR YSLDVWS

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against POR 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)
0.26
Highest tissue expression
293 nTPM

Expression across tissuesHPA

Tissue

  • liver: 293 nTPM
  • adrenal gland: 189 nTPM
  • thyroid gland: 123 nTPM
  • seminal vesicle: 107 nTPM
  • duodenum: 100 nTPM
  • small intestine: 87 nTPM

Single-cell type

  • hepatocytes: 710 nCPM
  • neutrophils: 513 nCPM
  • enterocytes: 378 nCPM
  • syncytiotrophoblasts: 263 nCPM
  • esophageal apical cells: 217 nCPM
  • proximal tubule cells: 192 nCPM

Immune cell

  • basophil: 67 nTPM
  • eosinophil: 60 nTPM
  • neutrophil: 54 nTPM
  • myeloid DC: 46 nTPM
  • classical monocyte: 43 nTPM
  • intermediate monocyte: 40 nTPM

Brain region

  • hypothalamus: 81 nTPM
  • thalamus: 63 nTPM
  • midbrain: 62 nTPM
  • medulla oblongata: 59 nTPM
  • pons: 54 nTPM
  • hippocampal formation: 54 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about POR.

Disease | AllUniProt

Conditions POR is implicated in, by any mechanism.

  • Antley-Bixler syndrome, with genital anomalies and disordered steroidogenesis (ABS1) MIM:201750
  • Disordered steroidogenesis due to cytochrome P450 oxidoreductase deficiency (DISPORD) MIM:613571

Disease | GeneticClinVar

101 pathogenic / likely-pathogenic of 951 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

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)
0.84
gnomAD pLI
0
gnomAD missense Z
-0.07
DepMap mean gene effect
-0.05
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 10% 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

InteractionsUniProt · HPA

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

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

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