Seroatlas · Human Serome Atlas

SLC4A5

Electrogenic sodium bicarbonate cotransporter 4

Also known as: NBC4, S4A5_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q9BY07
Gene
SLC4A5
Ensembl
ENSG00000188687
Chromosome
2
Canonical length
1137 aa
Protein class
Cancer-related genes, Metabolic proteins, Predicted intracellular proteins, Predicted membrane proteins, Transporters

OverviewNCBI Gene

This gene encodes a member of the sodium bicarbonate cotransporter (NBC) family, part of the bicarbonate transporter superfamily. Sodium bicarbonate cotransporters are involved in intracellular pH regulation and electroneural or electrogenic sodium bicarbonate transport. This protein is thought to be an integral membrane protein. Multiple transcript variants encoding different isoforms have been found for this gene, but the biological validity of some variants has not been determined. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

1137 residues, UniProt reviewed canonical sequence.

>Q9BY07|SLC4A5
     1  MKVKEEKAGV GKLDHTNHRR RFPDQKECPP IHIGLPVPTY PQRKTDQKGH LSGLQKVHWG
    61  LRPDQPQQEL TGPGSGASSQ DSSMDLISRT RSPAAEQLQD ILGEEDEAPN PTLFTEMDTL
   121  QHDGDQMEWK ESARWIKFEE KVEEGGERWS KPHVSTLSLH SLFELRTCLQ TGTVLLDLDS
   181  GSLPQIIDDV IEKQIEDGLL RPELRERVSY VLLRRHRHQT KKPIHRSLAD IGKSVSTTNR
   241  SPARSPGAGP SLHHSTEDLR MRQSANYGRL CHAQSRSMND ISLTPNTDQR KNKFMKKIPK
   301  DSEASNVLVG EVDFLDQPFI AFVRLIQSAM LGGVTEVPVP TRFLFILLGP SGRAKSYNEI
   361  GRAIATLMVD DLFSDVAYKA RNREDLIAGI DEFLDEVIVL PPGEWDPNIR IEPPKKVPSA
   421  DKRKSVFSLA ELGQMNGSVG GGGGAPGGGN GGGGGGGSGG GAGSGGAGGT SSGDDGEMPA
   481  MHEIGEELIW TGRFFGGLCL DIKRKLPWFP SDFYDGFHIQ SISAILFIYL GCITNAITFG
   541  GLLGDATDNY QGVMESFLGT AMAGSLFCLF SGQPLIILSS TGPILIFEKL LFDFSKGNGL
   601  DYMEFRLWIG LHSAVQCLIL VATDASFIIK YITRFTEEGF STLISFIFIY DAIKKMIGAF
   661  KYYPINMDFK PNFITTYKCE CVAPDTVNTT VFNASAPLAP DTNASLYNLL NLTALDWSLL
   721  SKKECLSYGG RLLGNSCKFI PDLALMSFIL FFGTYSMTLT LKKFKFSRYF PTKVRALVAD
   781  FSIVFSILMF CGIDACFGLE TPKLHVPSVI KPTRPDRGWF VAPFGKNPWW VYPASILPAL
   841  LVTILIFMDQ QITAVIVNRK ENKLKKAAGY HLDLFWVGIL MALCSFMGLP WYVAATVISI
   901  AHIDSLKMET ETSAPGEQPQ FLGVREQRVT GIIVFILTGI SVFLAPILKC IPLPVLYGVF
   961  LYMGVASLNG IQMGTGGSEF KIQKKLTPFW ERCKLFLMPA KHQPDHAFLR HVPLRRIHLF
  1021  TLVQILCLAV LWILKSTVAA IIFPVMILGL IIVRRLLDFI FSQHDLAWID NILPEKEKKE
  1081  TDKKRKRKKG AHEDCDEEPQ FPPPSVIKIP MESVQSDPQN GIHCIARKRS SSWSYSL

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against SLC4A5 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
12
Mean surface accessibility (rSASA)
0.37
Highest tissue expression
42 nTPM

Expression across tissuesHPA

Tissue

  • choroid plexus: 42 nTPM
  • retina: 39 nTPM
  • thyroid gland: 25 nTPM
  • testis: 15 nTPM
  • parathyroid gland: 12 nTPM
  • skin: 4.5 nTPM

Single-cell type

  • choroid plexus epithelial cells: 485 nCPM
  • oligodendrocytes: 47 nCPM
  • ependymal cells: 43 nCPM
  • astrocytes: 32 nCPM
  • bergmann glia: 24 nCPM
  • brain excitatory neurons: 17 nCPM

Immune cell

  • basophil: 4 nTPM
  • plasmacytoid DC: 2.4 nTPM
  • neutrophil: 1.7 nTPM
  • T-reg: 1.2 nTPM
  • naive CD8 T-cell: 1 nTPM
  • memory CD4 T-cell: 0.9 nTPM

Brain region

  • choroid plexus: 161 nTPM
  • cerebellum: 32 nTPM
  • white matter: 23 nTPM
  • hippocampal formation: 20 nTPM
  • cerebral cortex: 19 nTPM
  • medulla oblongata: 19 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about SLC4A5.

Disease | ImmuneIEDB

Conditions an epitope on SLC4A5 was assayed in.

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)
0.75
gnomAD pLI
0
gnomAD missense Z
1.39
DepMap mean gene effect
-0.18
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 6% 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 SLC4A5 as an antibody target. Whether an autoantibody or antibody against SLC4A5 could matter depends on whether native SLC4A5 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

SLC4A5 is annotated at the cell surface, where native SLC4A5 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 SLC4A5 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/SLC4A5. 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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