AQP5

Protein identityUniProt · HPA

UniProt accession

P55064

Gene

AQP5

Ensembl

ENSG00000161798

Chromosome

12

Canonical length

265 aa

Protein class

Disease related genes, Human disease related genes, Metabolic proteins, Potential drug targets, Predicted membrane proteins, Transporters

Subcellular location

Plasma membrane

Quaternary structure

Homotetramer

OverviewNCBI Gene

Aquaporin 5 (AQP5) is a water channel protein. Aquaporins are a family of small integral membrane proteins related to the major intrinsic protein (MIP or AQP0). Aquaporin 5 plays a role in the generation of saliva, tears and pulmonary secretions. AQP0, AQP2, AQP5, and AQP6 are closely related and all map to 12q13. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

265 residues, UniProt reviewed canonical sequence.

>P55064|AQP5
     1  MKKEVCSVAF LKAVFAEFLA TLIFVFFGLG SALKWPSALP TILQIALAFG LAIGTLAQAL
    61  GPVSGGHINP AITLALLVGN QISLLRAFFY VAAQLVGAIA GAGILYGVAP LNARGNLAVN
   121  ALNNNTTQGQ AMVVELILTF QLALCIFAST DSRRTSPVGS PALSIGLSVT LGHLVGIYFT
   181  GCSMNPARSF GPAVVMNRFS PAHWVFWVGP IVGAVLAAIL YFYLLFPNSL SLSERVAIIK
   241  GTYEPDEDWE EQREERKKTM ELTTR

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against AQP5 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

586 nTPM

Expression across tissuesHPA

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about AQP5.

Disease | AllUniProt

Conditions AQP5 is implicated in, by any mechanism.

• Keratoderma, palmoplantar, Bothnian type (PPKB) MIM:600231

Disease | GeneticClinVar

5 pathogenic / likely-pathogenic of 87 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

• Palmoplantar keratoderma, Bothnian type

Disease | ImmuneIEDB

Conditions an epitope on AQP5 was assayed in.

• Sjogren's syndrome B cell
• autoimmune disease B cell
• systemic lupus erythematosus B cell
• rheumatoid arthritis B cell

Disease | AutoantibodyPubMed

Conditions in which antibodies against AQP5 are reported. Each links to that disease's full target list.

• Sjogren's Syndrome 9

ReferencesPubMed · IEDB

Publications for AQP5 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.

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. IEDB — curated epitope assays from the Immune Epitope Database (Vita et al., Nucleic Acids Research 2019). 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)

1.06

gnomAD pLI

0.05

gnomAD missense Z

0.38

DepMap mean gene effect

-0.01

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

• camera-type eye morphogenesis
• carbon dioxide transport
• cellular hypotonic response
• odontogenesis
• pancreatic juice secretion
• protein homotetramerization
• saliva secretion
• water transport

Molecular functions

• identical protein binding
• water channel activity

Cellular components

• apical plasma membrane
• basal plasma membrane
• cytoplasmic vesicle membrane
• endoplasmic reticulum
• extracellular exosome
• microvillus
• plasma membrane

Protein domainsUniProt · Pfam · InterPro

• Major intrinsic protein
• Major intrinsic protein, conserved site
• Aquaporin-like
• Aquaporin transporter
• Major intrinsic protein
• Aquaporin 5

KeywordsUniProt

• Cell membrane
• Cytoplasmic vesicle
• Glycoprotein
• Membrane
• Palmoplantar keratoderma
• Repeat
• Transmembrane
• Transmembrane helix
• Transport

InteractionsUniProt · HPA

Protein binding partners of AQP5 in the human serome: UniProt-annotated complex subunits plus reported interactors. Each links to its own Seroatlas record.

• TRPV4