Seroatlas · Human Serome Atlas

PON3

Serum paraoxonase/lactonase 3

Also known as: PON3_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q15166
Gene
PON3
Ensembl
ENSG00000105852
Chromosome
7
Canonical length
354 aa
Protein class
Candidate cardiovascular disease genes, Enzymes, Metabolic proteins, Plasma proteins, Predicted secreted proteins
Secretome location
Secreted to blood
Quaternary structure
Homodimer

OverviewNCBI Gene

This gene is a member of the paraoxonase family and lies in a cluster on chromosome 7 with the other two family members. The encoded protein is secreted into the bloodstream and associates with high-density lipoprotein (HDL). The protein also rapidly hydrolyzes lactones and can inhibit the oxidation of low-density lipoprotein (LDL), a function that is believed to slow the initiation and progression of atherosclerosis. Alternatively spliced variants which encode different protein isoforms have been described; however, only one has been fully characterized. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

354 residues, UniProt reviewed canonical sequence.

>Q15166|PON3
     1  MGKLVALVLL GVGLSLVGEM FLAFRERVNA SREVEPVEPE NCHLIEELES GSEDIDILPS
    61  GLAFISSGLK YPGMPNFAPD EPGKIFLMDL NEQNPRAQAL EISGGFDKEL FNPHGISIFI
   121  DKDNTVYLYV VNHPHMKSTV EIFKFEEQQR SLVYLKTIKH ELLKSVNDIV VLGPEQFYAT
   181  RDHYFTNSLL SFFEMILDLR WTYVLFYSPR EVKVVAKGFC SANGITVSAD QKYVYVADVA
   241  AKNIHIMEKH DNWDLTQLKV IQLGTLVDNL TVDPATGDIL AGCHPNPMKL LNYNPEDPPG
   301  SEVLRIQNVL SEKPRVSTVY ANNGSVLQGT SVASVYHGKI LIGTVFHKTL YCEL

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against PON3 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
Secreted
Secreted
Yes
Transmembrane segments
0
Mean surface accessibility (rSASA)
0.23
Highest tissue expression
576 nTPM

Expression across tissuesHPA

Tissue

  • liver: 576 nTPM
  • breast: 29 nTPM
  • salivary gland: 25 nTPM
  • pituitary gland: 24 nTPM
  • pancreas: 14 nTPM
  • lung: 13 nTPM

Single-cell type

  • hepatocytes: 660 nCPM
  • alveolar cells type 2: 73 nCPM
  • transitional alveolar cells: 68 nCPM
  • gonadotrophs: 59 nCPM
  • corticotrophs: 58 nCPM
  • pancreatic islet cells: 49 nCPM

Immune cell

  • basophil: 0 nTPM
  • classical monocyte: 0 nTPM
  • eosinophil: 0 nTPM
  • gdT-cell: 0 nTPM
  • intermediate monocyte: 0 nTPM
  • MAIT T-cell: 0 nTPM

Brain region

  • medulla oblongata: 3.9 nTPM
  • pons: 3.4 nTPM
  • midbrain: 2.2 nTPM
  • thalamus: 2.1 nTPM
  • hypothalamus: 2 nTPM
  • amygdala: 1.9 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)
1.26
gnomAD pLI
0
gnomAD missense Z
-0.05
DepMap mean gene effect
0.03
DepMap dependency class
none

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 PON3 as an antibody target. Whether an autoantibody or antibody against PON3 could matter depends on whether native PON3 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

PON3 is annotated as secreted, so native PON3 circulates and is directly accessible to antibodies. Secreted and cell-surface proteins are the autoantibody targets most likely to act like drugs, blocking or depleting the native protein.

Annotation status

The present source text does not explicitly label PON3 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/PON3. 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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