Seroatlas · Human Serome Atlas

CA2

Carbonic anhydrase 2

Also known as: CA-II, CAH2_HUMAN, CAII, Car2

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

Protein identityUniProt · HPA

UniProt accession
P00918
Gene
CA2
Ensembl
ENSG00000104267
Chromosome
8
Canonical length
260 aa
Protein class
Disease related genes, Enzymes, FDA approved drug targets, Human disease related genes, Metabolic proteins, Plasma proteins, Predicted intracellular proteins

OverviewNCBI Gene

The protein encoded by this gene is one of several isozymes of carbonic anhydrase, which catalyzes reversible hydration of carbon dioxide. Defects in this enzyme are associated with osteopetrosis and renal tubular acidosis. Two transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jun 2014]

Canonical amino-acid sequenceUniProt

260 residues, UniProt reviewed canonical sequence.

>P00918|CA2
     1  MSHHWGYGKH NGPEHWHKDF PIAKGERQSP VDIDTHTAKY DPSLKPLSVS YDQATSLRIL
    61  NNGHAFNVEF DDSQDKAVLK GGPLDGTYRL IQFHFHWGSL DGQGSEHTVD KKKYAAELHL
   121  VHWNTKYGDF GKAVQQPDGL AVLGIFLKVG SAKPGLQKVV DVLDSIKTKG KSADFTNFDP
   181  RGLLPESLDY WTYPGSLTTP PLLECVTWIV LKEPISVSSE QVLKFRKLNF NGEGEPEELM
   241  VDNWRPAQPL KNRQIKASFK

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against CA2 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
Cell surface
Secreted
No
Transmembrane segments
0
Mean surface accessibility (rSASA)
0.23
Highest tissue expression
1,047 nTPM

Expression across tissuesHPA

Tissue

  • stomach: 1,047 nTPM
  • choroid plexus: 944 nTPM
  • colon: 644 nTPM
  • rectum: 605 nTPM
  • retina: 362 nTPM
  • kidney: 309 nTPM

Single-cell type

  • foveolar cells: 3,492 nCPM
  • colonocytes: 2,145 nCPM
  • erythrocyte progenitors: 1,624 nCPM
  • müller glia: 1,235 nCPM
  • parietal cells: 810 nCPM
  • platelets: 723 nCPM

Immune cell

  • basophil: 51 nTPM
  • total PBMC: 33 nTPM
  • myeloid DC: 15 nTPM
  • intermediate monocyte: 15 nTPM
  • non-classical monocyte: 13 nTPM
  • neutrophil: 13 nTPM

Brain region

  • choroid plexus: 825 nTPM
  • white matter: 174 nTPM
  • basal ganglia: 139 nTPM
  • cerebellum: 131 nTPM
  • medulla oblongata: 118 nTPM
  • thalamus: 116 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about CA2.

Disease | AllUniProt

Conditions CA2 is implicated in, by any mechanism.

  • Osteopetrosis, autosomal recessive 3 (OPTB3) MIM:259730

Disease | GeneticClinVar

23 pathogenic / likely-pathogenic of 223 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

Disease | AutoantibodyPubMed

Conditions in which antibodies against CA2 are reported. Each links to that disease's full target list.

Showing 5 of 10 — disease pages carrying at least 10 antigens.

ReferencesPubMed · IEDB

Publications for CA2 from three distinct lines of evidence, kept separate because they answer different questions: whether antibodies are directed at the protein, whether a B-cell epitope has been mapped on it, and whether a T-cell epitope has. Each is labelled with its source.

Reference: AutoantibodyPubMed

43 publications

Show 20 more of 43 total

Sources: PubMed — antigen-level antibody evidence from a custom retrieval. Records matching a controlled set of autoantibody terms (the MeSH descriptors Autoantibodies and Autoantigens, with title and abstract term variants) were obtained through NCBI E-utilities, and their titles and abstracts parsed for constructions that direct an antibody at a named protein rather than for co-occurrence. Captured names were resolved against UniProt nomenclature and each antigen adjudicated individually against the source text. Bibliographic records from PubMed and MeSH, U.S. National Library of Medicine; citation metrics from NIH iCite (Hutchins et al., PLoS Biology 2016). Titles link to PubMed; abstracts are not reproduced here. The NLM does not endorse this analysis.

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)
1.37
gnomAD pLI
0
gnomAD missense Z
0.36
DepMap mean gene effect
0.02
DepMap dependency class
none

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

InteractionsUniProt · HPA

Protein binding partners of CA2 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 CA2 as an antibody target. Whether an autoantibody or antibody against CA2 could matter depends on whether native CA2 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

CA2 is annotated at the cell surface, where native CA2 is exposed to circulating antibodies and is a prime autoantibody target that could block, deplete, or overstimulate it.

Annotation status

The present source text does not explicitly label CA2 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/CA2. 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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