Seroatlas · Human Serome Atlas

PPIAL4A

Peptidyl-prolyl cis-trans isomerase A-like 4A

Also known as: COAS2, PAL4A_HUMAN, PPIAL4, PPIAL4B

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

Protein identityUniProt · HPA

UniProt accession
Q9Y536
Gene
PPIAL4A
Ensembl
ENSG00000263353
Chromosome
1
Canonical length
164 aa
Protein class
Enzymes, Metabolic proteins, Predicted intracellular proteins

OverviewNCBI Gene

Predicted to enable cyclosporin A binding activity and peptidyl-prolyl cis-trans isomerase activity. Predicted to be involved in protein folding. Located in extracellular exosome. [provided by Alliance of Genome Resources, Jul 2025]

Canonical amino-acid sequenceUniProt

164 residues, UniProt reviewed canonical sequence.

>Q9Y536|PPIAL4A
     1  MVNSVVFFDI TVDGKPLGRI SIKLFADKIL KTAENFRALS TGEKGFRYKG SCFHRIIPGF
    61  MCQGGDFTRH NGTGDKSIYG EKFDDENLIR KHTGSGILSM ANAGPNTNGS QFFICAAKTE
   121  WLDGKHVAFG KVKERVNIVE AMEHFGYRNS KTSKKITIAD CGQF

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against PPIAL4A 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
0.5 nTPM

Expression across tissuesHPA

Tissue

  • bone marrow: 0.5 nTPM
  • appendix: 0.2 nTPM
  • cerebellum: 0.2 nTPM
  • cerebral cortex: 0.2 nTPM
  • duodenum: 0.2 nTPM
  • liver: 0.2 nTPM

Single-cell type

  • distal convoluted tubule cells: 0.1 nCPM
  • respiratory ciliated cells: 0.1 nCPM
  • transitional alveolar cells: 0.1 nCPM
  • adipocytes: 0 nCPM
  • adrenal cortex cells: 0 nCPM
  • adrenal medulla cells: 0 nCPM

Immune cell

  • total PBMC: 1.9 nTPM
  • memory B-cell: 1.2 nTPM
  • myeloid DC: 1.2 nTPM
  • plasmacytoid DC: 1.2 nTPM
  • memory CD8 T-cell: 1 nTPM
  • NK-cell: 1 nTPM

Brain region

  • medulla oblongata: 1.2 nTPM
  • thalamus: 0.7 nTPM
  • white matter: 0.6 nTPM
  • cerebral cortex: 0.5 nTPM
  • pons: 0.5 nTPM
  • basal ganglia: 0.4 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 missense Z
-0.51

OntologyGO

Biological processes

Molecular functions

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads PPIAL4A as an antibody target. Whether an autoantibody or antibody against PPIAL4A could matter depends on whether native PPIAL4A is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

PPIAL4A 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 PPIAL4A as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/PPIAL4A. 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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