Seroatlas · Human Serome Atlas

PTGIS

Prostacyclin synthase

Also known as: CYP8A1, PGIS, PTGIS_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q16647
Gene
PTGIS
Ensembl
ENSG00000124212
Chromosome
20
Canonical length
500 aa
Protein class
Disease related genes, Enzymes, FDA approved drug targets, Metabolic proteins, Plasma proteins, Predicted membrane proteins
Subcellular location
Endoplasmic reticulum,Golgi apparatus,Cytosol

OverviewNCBI Gene

This gene encodes a member of the cytochrome P450 superfamily of enzymes. The cytochrome P450 proteins are monooxygenases which catalyze many reactions involved in drug metabolism and synthesis of cholesterol, steroids and other lipids. However, this protein is considered a member of the cytochrome P450 superfamily on the basis of sequence similarity rather than functional similarity. This endoplasmic reticulum membrane protein catalyzes the conversion of prostglandin H2 to prostacyclin (prostaglandin I2), a potent vasodilator and inhibitor of platelet aggregation. An imbalance of prostacyclin and its physiological antagonist thromboxane A2 contribute to the development of myocardial infarction, stroke, and atherosclerosis. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

500 residues, UniProt reviewed canonical sequence.

>Q16647|PTGIS
     1  MAWAALLGLL AALLLLLLLS RRRTRRPGEP PLDLGSIPWL GYALDFGKDA ASFLTRMKEK
    61  HGDIFTILVG GRYVTVLLDP HSYDAVVWEP RTRLDFHAYA IFLMERIFDV QLPHYSPSDE
   121  KARMKLTLLH RELQALTEAM YTNLHAVLLG DATEAGSGWH EMGLLDFSYS FLLRAGYLTL
   181  YGIEALPRTH ESQAQDRVHS ADVFHTFRQL DRLLPKLARG SLSVGDKDHM CSVKSRLWKL
   241  LSPARLARRA HRSKWLESYL LHLEEMGVSE EMQARALVLQ LWATQGNMGP AAFWLLLFLL
   301  KNPEALAAVR GELESILWQA EQPVSQTTTL PQKVLDSTPV LDSVLSESLR LTAAPFITRE
   361  VVVDLAMPMA DGREFNLRRG DRLLLFPFLS PQRDPEIYTD PEVFKYNRFL NPDGSEKKDF
   421  YKDGKRLKNY NMPWGAGHNH CLGRSYAVNS IKQFVFLVLV HLDLELINAD VEIPEFDLSR
   481  YGFGLMQPEH DVPVRYRIRP

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against PTGIS 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)
0.24
Highest tissue expression
124 nTPM

Expression across tissuesHPA

Tissue

  • blood vessel: 124 nTPM
  • endometrium: 77 nTPM
  • fallopian tube: 77 nTPM
  • urinary bladder: 75 nTPM
  • adipose tissue: 41 nTPM
  • heart muscle: 39 nTPM

Single-cell type

  • mesothelial cells: 336 nCPM
  • fibro-adipogenic progenitors: 237 nCPM
  • peritubular myoid cells: 227 nCPM
  • smooth muscle cells: 205 nCPM
  • fibroblasts: 172 nCPM
  • epicardial cells: 162 nCPM

Immune cell

  • basophil: 0.6 nTPM
  • neutrophil: 0.4 nTPM
  • classical monocyte: 0.1 nTPM
  • naive B-cell: 0.1 nTPM
  • NK-cell: 0.1 nTPM
  • plasmacytoid DC: 0.1 nTPM

Brain region

  • basal ganglia: 7.1 nTPM
  • cerebral cortex: 5.9 nTPM
  • choroid plexus: 5.8 nTPM
  • hypothalamus: 3.9 nTPM
  • medulla oblongata: 3.2 nTPM
  • spinal cord: 3.1 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about PTGIS.

Disease | AllUniProt

Conditions PTGIS is implicated in, by any mechanism.

Disease | GeneticClinVar

2 pathogenic / likely-pathogenic of 118 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)
1.1
gnomAD pLI
0
gnomAD missense Z
-0.37
DepMap mean gene effect
-0.12
DepMap dependency class
selective

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

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

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