Seroatlas · Human Serome Atlas

PPIE

Peptidyl-prolyl cis-trans isomerase E

Also known as: CyP-33, MGC111222, MGC3736, PPIE_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q9UNP9
Gene
PPIE
Ensembl
ENSG00000084072
Chromosome
1
Canonical length
301 aa
Protein class
Enzymes, Metabolic proteins, Predicted intracellular proteins
Subcellular location
Nuclear speckles

OverviewNCBI Gene

The protein encoded by this gene is a member of the peptidyl-prolyl cis-trans isomerase (PPIase) family. PPIases catalyze the cis-trans isomerization of proline imidic peptide bonds in oligopeptides and accelerate the folding of proteins. This protein contains a highly conserved cyclophilin (CYP) domain as well as an RNA-binding domain. It was shown to possess PPIase and protein folding activities, and it also exhibits RNA-binding activity. Alternative splicing results in multiple transcript variants. A related pseudogene, which is also located on chromosome 1, has been identified. [provided by RefSeq, Aug 2010]

Canonical amino-acid sequenceUniProt

301 residues, UniProt reviewed canonical sequence.

>Q9UNP9|PPIE
     1  MATTKRVLYV GGLAEEVDDK VLHAAFIPFG DITDIQIPLD YETEKHRGFA FVEFELAEDA
    61  AAAIDNMNES ELFGRTIRVN LAKPMRIKEG SSRPVWSDDD WLKKFSGKTL EENKEEEGSE
   121  PPKAETQEGE PIAKKARSNP QVYMDIKIGN KPAGRIQMLL RSDVVPMTAE NFRCLCTHEK
   181  GFGFKGSSFH RIIPQFMCQG GDFTNHNGTG GKSIYGKKFD DENFILKHTG PGLLSMANSG
   241  PNTNGSQFFL TCDKTDWLDG KHVVFGEVTE GLDVLRQIEA QGSKDGKPKQ KVIIADCGEY
   301  V

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against PPIE 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)
0.32
Highest tissue expression
35 nTPM

Expression across tissuesHPA

Tissue

  • pancreas: 35 nTPM
  • fallopian tube: 32 nTPM
  • ovary: 31 nTPM
  • colon: 31 nTPM
  • blood vessel: 31 nTPM
  • skeletal muscle: 29 nTPM

Single-cell type

  • oocytes: 115 nCPM
  • late primary spermatocytes: 105 nCPM
  • late spermatids: 102 nCPM
  • megakaryocytes: 80 nCPM
  • esophageal basal cells: 77 nCPM
  • migrating cytotrophoblasts: 74 nCPM

Immune cell

  • NK-cell: 125 nTPM
  • total PBMC: 124 nTPM
  • naive B-cell: 111 nTPM
  • memory B-cell: 109 nTPM
  • naive CD4 T-cell: 105 nTPM
  • T-reg: 103 nTPM

Brain region

  • white matter: 23 nTPM
  • spinal cord: 22 nTPM
  • medulla oblongata: 20 nTPM
  • basal ganglia: 20 nTPM
  • cerebellum: 20 nTPM
  • cerebral cortex: 20 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)
0.45
gnomAD pLI
0.73
gnomAD missense Z
1.25
DepMap mean gene effect
-0.7
DepMap dependency class
common

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

InteractionsUniProt · HPA

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

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

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