Seroatlas · Human Serome Atlas

ATP6AP1

V-type proton ATPase subunit S1

Also known as: 16A, Ac45, ATP6IP1, ATP6S1, CF2, ORF, VAS1_HUMAN, VATPS1, XAP-3, XAP3

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

Protein identityUniProt · HPA

UniProt accession
Q15904
Gene
ATP6AP1
Ensembl
ENSG00000071553
Chromosome
X
Canonical length
470 aa
Protein class
Disease related genes, Human disease related genes, Metabolic proteins, Plasma proteins, Potential drug targets, Predicted intracellular proteins, Predicted membrane proteins, Transporters

OverviewNCBI Gene

This gene encodes a component of a multisubunit enzyme that mediates acidification of eukaryotic intracellular organelles. Vacuolar ATPase (V-ATPase) is comprised of a cytosolic V1 (site of the ATP catalytic site) and a transmembrane V0 domain. V-ATPase dependent organelle acidification is necessary for such intracellular processes as protein sorting, zymogen activation, and receptor-mediated endocytosis. The encoded protein of this gene may assist in the V-ATPase-mediated acidification of neuroendocrine secretory granules. This protein may also play a role in early development. [provided by RefSeq, Aug 2013]

Canonical amino-acid sequenceUniProt

470 residues, UniProt reviewed canonical sequence.

>Q15904|ATP6AP1
     1  MMAAMATARV RMGPRCAQAL WRMPWLPVFL SLAAAAAAAA AEQQVPLVLW SSDRDLWAPA
    61  ADTHEGHITS DLQLSTYLDP ALELGPRNVL LFLQDKLSIE DFTAYGGVFG NKQDSAFSNL
   121  ENALDLAPSS LVLPAVDWYA VSTLTTYLQE KLGASPLHVD LATLRELKLN ASLPALLLIR
   181  LPYTASSGLM APREVLTGND EVIGQVLSTL KSEDVPYTAA LTAVRPSRVA RDVAVVAGGL
   241  GRQLLQKQPV SPVIHPPVSY NDTAPRILFW AQNFSVAYKD QWEDLTPLTF GVQELNLTGS
   301  FWNDSFARLS LTYERLFGTT VTFKFILANR LYPVSARHWF TMERLEVHSN GSVAYFNASQ
   361  VTGPSIYSFH CEYVSSLSKK GSLLVARTQP SPWQMMLQDF QIQAFNVMGE QFSYASDCAS
   421  FFSPGIWMGL LTSLFMLFIF TYGLHMILSL KTMDRFDDHK GPTISLTQIV

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against ATP6AP1 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
Other membrane
Secreted
No
Transmembrane segments
1
Mean surface accessibility (rSASA)
0.37
Highest tissue expression
214 nTPM

Expression across tissuesHPA

Tissue

  • choroid plexus: 214 nTPM
  • parathyroid gland: 165 nTPM
  • cerebral cortex: 149 nTPM
  • cerebellum: 141 nTPM
  • epididymis: 137 nTPM
  • hypothalamus: 120 nTPM

Single-cell type

  • esophageal apical cells: 334 nCPM
  • hofbauer cells: 310 nCPM
  • syncytiotrophoblasts: 231 nCPM
  • kupffer cells: 182 nCPM
  • cytotrophoblasts: 160 nCPM
  • neutrophils: 147 nCPM

Immune cell

  • myeloid DC: 377 nTPM
  • eosinophil: 365 nTPM
  • neutrophil: 328 nTPM
  • intermediate monocyte: 314 nTPM
  • classical monocyte: 296 nTPM
  • non-classical monocyte: 257 nTPM

Brain region

  • choroid plexus: 170 nTPM
  • white matter: 165 nTPM
  • pons: 163 nTPM
  • cerebral cortex: 153 nTPM
  • hypothalamus: 152 nTPM
  • basal ganglia: 135 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about ATP6AP1.

Disease | AllUniProt

Conditions ATP6AP1 is implicated in, by any mechanism.

Disease | GeneticClinVar

13 pathogenic / likely-pathogenic of 401 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

  • Immunodeficiency 47

Disease | ImmuneIEDB

Conditions an epitope on ATP6AP1 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)
0.21
gnomAD pLI
0.99
gnomAD missense Z
1.53
DepMap mean gene effect
-0.97
DepMap dependency class
common

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 7% 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 ATP6AP1 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 ATP6AP1 as an antibody target. Whether an autoantibody or antibody against ATP6AP1 could matter depends on whether native ATP6AP1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

ATP6AP1 is annotated as predominantly intracellular. Intracellular proteins are common autoantibody markers, becoming visible to the immune system after cell injury or altered processing, but are usually markers of disease rather than direct drivers.

Annotation status

The present source text does not explicitly label ATP6AP1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/ATP6AP1. 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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