Seroatlas · Human Serome Atlas

PNP

Purine nucleoside phosphorylase

Also known as: NP, PNPH_HUMAN, PUNP

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

Protein identityUniProt · HPA

UniProt accession
P00491
Gene
PNP
Ensembl
ENSG00000198805
Chromosome
14
Canonical length
289 aa
Protein class
Disease related genes, Enzymes, FDA approved drug targets, Human disease related genes, Metabolic proteins, Plasma proteins, Predicted intracellular proteins
Subcellular location
Cytosol
Quaternary structure
Homotrimer

OverviewNCBI Gene

This gene encodes an enzyme which reversibly catalyzes the phosphorolysis of purine nucleosides. The enzyme is trimeric, containing three identical subunits. Mutations which result in nucleoside phosphorylase deficiency result in defective T-cell (cell-mediated) immunity but can also affect B-cell immunity and antibody responses. Neurologic disorders may also be apparent in patients with immune defects. A known polymorphism at aa position 51 that does not affect enzyme activity has been described. A pseudogene has been identified on chromosome 2. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

289 residues, UniProt reviewed canonical sequence.

>P00491|PNP
     1  MENGYTYEDY KNTAEWLLSH TKHRPQVAII CGSGLGGLTD KLTQAQIFDY GEIPNFPRST
    61  VPGHAGRLVF GFLNGRACVM MQGRFHMYEG YPLWKVTFPV RVFHLLGVDT LVVTNAAGGL
   121  NPKFEVGDIM LIRDHINLPG FSGQNPLRGP NDERFGDRFP AMSDAYDRTM RQRALSTWKQ
   181  MGEQRELQEG TYVMVAGPSF ETVAECRVLQ KLGADAVGMS TVPEVIVARH CGLRVFGFSL
   241  ITNKVIMDYE SLEKANHEEV LAAGKQAAQK LEQFVSILMA SIPLPDKAS

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against PNP 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
Intracellular
Secreted
No
Transmembrane segments
0
Mean surface accessibility (rSASA)
0.24
Highest tissue expression
551 nTPM

Expression across tissuesHPA

Tissue

  • epididymis: 551 nTPM
  • bone marrow: 299 nTPM
  • kidney: 192 nTPM
  • placenta: 124 nTPM
  • duodenum: 113 nTPM
  • urinary bladder: 93 nTPM

Single-cell type

  • syncytiotrophoblasts: 732 nCPM
  • epididymal principal cells: 505 nCPM
  • cytotrophoblasts: 472 nCPM
  • breast lactating cells: 263 nCPM
  • megakaryocytes: 210 nCPM
  • platelets: 208 nCPM

Immune cell

  • MAIT T-cell: 73 nTPM
  • myeloid DC: 48 nTPM
  • memory CD8 T-cell: 45 nTPM
  • memory CD4 T-cell: 44 nTPM
  • gdT-cell: 39 nTPM
  • NK-cell: 38 nTPM

Brain region

  • spinal cord: 25 nTPM
  • cerebellum: 24 nTPM
  • cerebral cortex: 24 nTPM
  • thalamus: 21 nTPM
  • medulla oblongata: 20 nTPM
  • pons: 19 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about PNP.

Disease | AllUniProt

Conditions PNP is implicated in, by any mechanism.

  • Purine nucleoside phosphorylase deficiency (PNPD) MIM:613179

Disease | GeneticClinVar

38 pathogenic / likely-pathogenic of 310 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

Disease | ImmuneIEDB

Conditions an epitope on PNP was assayed in.

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)
1.15
gnomAD pLI
0
gnomAD missense Z
0.44
DepMap mean gene effect
0
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 5% 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 PNP as an antibody target. Whether an autoantibody or antibody against PNP could matter depends on whether native PNP is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

PNP 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.

Source-annotated serology context

The source annotations explicitly mention antibody, autoantibody, autoantigen, or autoimmune context. This is biological context, not study-specific reactivity.

  • Mutations which result in nucleoside phosphorylase deficiency result in defective T-cell (cell-mediated) immunity but can also affect B-cell immunity and antibody responses.

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