Seroatlas · Human Serome Atlas

CPA3

Mast cell carboxypeptidase A

Also known as: CBPA3_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
P15088
Gene
CPA3
Ensembl
ENSG00000163751
Chromosome
3
Canonical length
417 aa
Protein class
Enzymes, Metabolic proteins, Plasma proteins, Predicted secreted proteins
Subcellular location
Nucleoplasm,Golgi apparatus
Secretome location
Secreted to blood

OverviewNCBI Gene

This gene encodes a member of the carboxypeptidase A family of zinc metalloproteases. The encoded preproprotein is proteolytically processed to generate a mature protease that is released by mast cells and may be involved in the degradation of endogenous proteins and the inactivation of venom-associated peptides. Expression of this gene may be elevated in human asthma patients. [provided by RefSeq, Nov 2015]

Canonical amino-acid sequenceUniProt

417 residues, UniProt reviewed canonical sequence.

>P15088|CPA3
     1  MRLILPVGLI ATTLAIAPVR FDREKVFRVK PQDEKQADII KDLAKTNELD FWYPGATHHV
    61  AANMMVDFRV SEKESQAIQS ALDQNKMHYE ILIHDLQEEI EKQFDVKEDI PGRHSYAKYN
   121  NWEKIVAWTE KMMDKYPEMV SRIKIGSTVE DNPLYVLKIG EKNERRKAIF TDCGIHAREW
   181  VSPAFCQWFV YQATKTYGRN KIMTKLLDRM NFYILPVFNV DGYIWSWTKN RMWRKNRSKN
   241  QNSKCIGTDL NRNFNASWNS IPNTNDPCAD NYRGSAPESE KETKAVTNFI RSHLNEIKVY
   301  ITFHSYSQML LFPYGYTSKL PPNHEDLAKV AKIGTDVLST RYETRYIYGP IESTIYPISG
   361  SSLDWAYDLG IKHTFAFELR DKGKFGFLLP ESRIKPTCRE TMLAVKFIAK YILKHTS

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against CPA3 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)
0.23
Highest tissue expression
105 nTPM

Expression across tissuesHPA

Tissue

  • gallbladder: 105 nTPM
  • lung: 81 nTPM
  • cervix: 56 nTPM
  • rectum: 53 nTPM
  • urinary bladder: 50 nTPM
  • small intestine: 43 nTPM

Single-cell type

  • mast cells: 3,889 nCPM
  • megakaryocyte progenitors: 167 nCPM
  • megakaryocyte-erythroid progenitors: 126 nCPM
  • hematopoietic stem cells: 28 nCPM
  • pancreatic acinar cells: 10 nCPM
  • pdcs: 7.3 nCPM

Immune cell

  • basophil: 1,120 nTPM
  • total PBMC: 2.9 nTPM
  • eosinophil: 0.7 nTPM
  • neutrophil: 0.4 nTPM
  • non-classical monocyte: 0.2 nTPM
  • intermediate monocyte: 0.1 nTPM

Brain region

  • basal ganglia: 0.9 nTPM
  • choroid plexus: 0.7 nTPM
  • thalamus: 0.2 nTPM
  • medulla oblongata: 0.1 nTPM
  • amygdala: 0 nTPM
  • cerebellum: 0 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)
1.32
gnomAD pLI
0
gnomAD missense Z
-0.69
DepMap mean gene effect
0.09
DepMap dependency class
none

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 3% 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 CPA3 as an antibody target. Whether an autoantibody or antibody against CPA3 could matter depends on whether native CPA3 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

CPA3 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 CPA3 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/CPA3. 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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