Seroatlas · Human Serome Atlas

AQP3

Aquaporin-3

Also known as: AQP3_HUMAN, GIL

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

Protein identityUniProt · HPA

UniProt accession
Q92482
Gene
AQP3
Ensembl
ENSG00000165272
Chromosome
9
Canonical length
292 aa
Protein class
Blood group antigen proteins, Metabolic proteins, Plasma proteins, Predicted membrane proteins, Transporters
Subcellular location
Plasma membrane
Quaternary structure
Homotetramer

OverviewNCBI Gene

This gene encodes the water channel protein aquaporin 3. Aquaporins are a family of small integral membrane proteins related to the major intrinsic protein, also known as aquaporin 0. Aquaporin 3 is localized at the basal lateral membranes of collecting duct cells in the kidney. In addition to its water channel function, aquaporin 3 has been found to facilitate the transport of nonionic small solutes such as urea and glycerol, but to a smaller degree. It has been suggested that water channels can be functionally heterogeneous and possess water and solute permeation mechanisms. Alternative splicing of this gene results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Dec 2015]

Canonical amino-acid sequenceUniProt

292 residues, UniProt reviewed canonical sequence.

>Q92482|AQP3
     1  MGRQKELVSR CGEMLHIRYR LLRQALAECL GTLILVMFGC GSVAQVVLSR GTHGGFLTIN
    61  LAFGFAVTLG ILIAGQVSGA HLNPAVTFAM CFLAREPWIK LPIYTLAQTL GAFLGAGIVF
   121  GLYYDAIWHF ADNQLFVSGP NGTAGIFATY PSGHLDMING FFDQFIGTAS LIVCVLAIVD
   181  PYNNPVPRGL EAFTVGLVVL VIGTSMGFNS GYAVNPARDF GPRLFTALAG WGSAVFTTGQ
   241  HWWWVPIVSP LLGSIAGVFV YQLMIGCHLE QPPPSNEEEN VKLAHVKHKE QI

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against AQP3 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
6
Mean surface accessibility (rSASA)
0.28
Highest tissue expression
1,458 nTPM

Expression across tissuesHPA

Tissue

  • esophagus: 1,458 nTPM
  • urinary bladder: 642 nTPM
  • skin: 554 nTPM
  • vagina: 505 nTPM
  • salivary gland: 377 nTPM
  • cervix: 331 nTPM

Single-cell type

  • esophageal suprabasal cells: 7,328 nCPM
  • esophageal apical cells: 4,827 nCPM
  • esophageal basal cells: 3,864 nCPM
  • suprabasal keratinocytes: 2,386 nCPM
  • ocular epithelial cells: 1,729 nCPM
  • basal keratinocytes: 1,613 nCPM

Immune cell

  • T-reg: 206 nTPM
  • MAIT T-cell: 182 nTPM
  • memory CD4 T-cell: 172 nTPM
  • naive CD4 T-cell: 98 nTPM
  • memory CD8 T-cell: 53 nTPM
  • naive CD8 T-cell: 47 nTPM

Brain region

  • pons: 47 nTPM
  • medulla oblongata: 23 nTPM
  • hippocampal formation: 14 nTPM
  • cerebral cortex: 9.9 nTPM
  • cerebellum: 8.1 nTPM
  • choroid plexus: 6.2 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)
0.64
gnomAD pLI
0.13
gnomAD missense Z
1.58
DepMap mean gene effect
0.03
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

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads AQP3 as an antibody target. Whether an autoantibody or antibody against AQP3 could matter depends on whether native AQP3 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

AQP3 is annotated at the cell surface, where native AQP3 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 AQP3 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/AQP3. 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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