Seroatlas · Human Serome Atlas

SLC4A2

Anion exchange protein 2

Also known as: AE2, B3A2_HUMAN, BND3L, EPB3L1, HKB3, NBND3

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

Protein identityUniProt · HPA

UniProt accession
P04920
Gene
SLC4A2
Ensembl
ENSG00000164889
Chromosome
7
Canonical length
1241 aa
Protein class
Metabolic proteins, Predicted intracellular proteins, Predicted membrane proteins, Transporters
Subcellular location
Nuclear speckles,Plasma membrane,Cytosol

OverviewNCBI Gene

This gene encodes a member of the anion exchanger family of membrane transport proteins. The encoded protein regulates intracellular pH, biliary bicarbonate secretion, and chloride uptake. Reduced expression of this gene may be associated with primary biliary cirrhosis (PBC) in human patients, while differential expression of this gene may be associated with malignant hepatocellular carcinoma, colon and gastric cancers. [provided by RefSeq, Nov 2016]

Canonical amino-acid sequenceUniProt

1241 residues, UniProt reviewed canonical sequence.

>P04920|SLC4A2
     1  MSSAPRRPAK GADSFCTPEP ESLGPGTPGF PEQEEDELHR TLGVERFEEI LQEAGSRGGE
    61  EPGRSYGEED FEYHRQSSHH IHHPLSTHLP PDARRRKTPQ GPGRKPRRRP GASPTGETPT
   121  IEEGEEDEDE ASEAEGARAL TQPSPVSTPS SVQFFLQEDD SADRKAERTS PSSPAPLPHQ
   181  EATPRASKGA QAGTQVEEAE AEAVAVASGT AGGDDGGASG RPLPKAQPGH RSYNLQERRR
   241  IGSMTGAEQA LLPRVPTDEI EAQTLATADL DLMKSHRFED VPGVRRHLVR KNAKGSTQSG
   301  REGREPGPTP RARPRAPHKP HEVFVELNEL LLDKNQEPQW RETARWIKFE EDVEEETERW
   361  GKPHVASLSF RSLLELRRTL AHGAVLLDLD QQTLPGVAHQ VVEQMVISDQ IKAEDRANVL
   421  RALLLKHSHP SDEKDFSFPR NISAGSLGSL LGHHHGQGAE SDPHVTEPLM GGVPETRLEV
   481  ERERELPPPA PPAGITRSKS KHELKLLEKI PENAEATVVL VGCVEFLSRP TMAFVRLREA
   541  VELDAVLEVP VPVRFLFLLL GPSSANMDYH EIGRSISTLM SDKQFHEAAY LADEREDLLT
   601  AINAFLDCSV VLPPSEVQGE ELLRSVAHFQ RQMLKKREEQ GRLLPTGAGL EPKSAQDKAL
   661  LQMVEAAGAA EDDPLRRTGR PFGGLIRDVR RRYPHYLSDF RDALDPQCLA AVIFIYFAAL
   721  SPAITFGGLL GEKTQDLIGV SELIMSTALQ GVVFCLLGAQ PLLVIGFSGP LLVFEEAFFS
   781  FCSSNHLEYL VGRVWIGFWL VFLALLMVAL EGSFLVRFVS RFTQEIFAFL ISLIFIYETF
   841  YKLVKIFQEH PLHGCSASNS SEVDGGENMT WAGARPTLGP GNRSLAGQSG QGKPRGQPNT
   901  ALLSLVLMAG TFFIAFFLRK FKNSRFFPGR IRRVIGDFGV PIAILIMVLV DYSIEDTYTQ
   961  KLSVPSGFSV TAPEKRGWVI NPLGEKSPFP VWMMVASLLP AILVFILIFM ETQITTLIIS
  1021  KKERMLQKGS GFHLDLLLIV AMGGICALFG LPWLAAATVR SVTHANALTV MSKAVAPGDK
  1081  PKIQEVKEQR VTGLLVALLV GLSIVIGDLL RQIPLAVLFG IFLYMGVTSL NGIQFYERLH
  1141  LLLMPPKHHP DVTYVKKVRT LRMHLFTALQ LLCLALLWAV MSTAASLAFP FILILTVPLR
  1201  MVVLTRIFTD REMKCLDANE AEPVFDEREG VDEYNEMPMP V

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against SLC4A2 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
10
Mean surface accessibility (rSASA)
0.42
Highest tissue expression
265 nTPM

Expression across tissuesHPA

Tissue

  • choroid plexus: 265 nTPM
  • stomach: 71 nTPM
  • parathyroid gland: 68 nTPM
  • pancreas: 50 nTPM
  • liver: 47 nTPM
  • colon: 40 nTPM

Single-cell type

  • retinal pigment epithelial cells: 333 nCPM
  • choroid plexus epithelial cells: 329 nCPM
  • parietal cells: 170 nCPM
  • syncytiotrophoblasts: 127 nCPM
  • alveolar cells type 1: 59 nCPM
  • tuft cells: 46 nCPM

Immune cell

  • plasmacytoid DC: 2.1 nTPM
  • classical monocyte: 1.6 nTPM
  • intermediate monocyte: 1.6 nTPM
  • myeloid DC: 1 nTPM
  • non-classical monocyte: 1 nTPM
  • memory B-cell: 0.9 nTPM

Brain region

  • choroid plexus: 1,044 nTPM
  • hippocampal formation: 82 nTPM
  • white matter: 80 nTPM
  • medulla oblongata: 69 nTPM
  • thalamus: 68 nTPM
  • pons: 61 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about SLC4A2.

Disease | AllUniProt

Conditions SLC4A2 is implicated in, by any mechanism.

  • Osteopetrosis, autosomal recessive 9 (OPTB9) MIM:620366

Disease | GeneticClinVar

3 pathogenic / likely-pathogenic of 219 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)
0.3
gnomAD pLI
0.99
gnomAD missense Z
2.97
DepMap mean gene effect
0.07
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 9% 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 SLC4A2 as an antibody target. Whether an autoantibody or antibody against SLC4A2 could matter depends on whether native SLC4A2 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

SLC4A2 is annotated at the cell surface, where native SLC4A2 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 SLC4A2 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/SLC4A2. 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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