Seroatlas · Human Serome Atlas

APTX

Aprataxin

Also known as: AOA, AOA1, APTX_HUMAN, AXA1, EAOH, EOAHA, FLJ20157

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

Protein identityUniProt · HPA

UniProt accession
Q7Z2E3
Gene
APTX
Ensembl
ENSG00000137074
Chromosome
9
Canonical length
356 aa
Protein class
Disease related genes, Enzymes, Human disease related genes, Potential drug targets, Predicted intracellular proteins
Subcellular location
Nucleoplasm,Nucleoli

OverviewNCBI Gene

This gene encodes a member of the histidine triad (HIT) superfamily. The encoded protein may play a role in single-stranded DNA repair through its nucleotide-binding activity and its diadenosine polyphosphate hydrolase activity. Mutations in this gene have been associated with ataxia-ocular apraxia. Alternatively spliced transcript variants have been identified for this gene.[provided by RefSeq, Aug 2010]

Canonical amino-acid sequenceUniProt

356 residues, UniProt reviewed canonical sequence.

>Q7Z2E3|APTX
     1  MSNVNLSVSD FWRVMMRVCW LVRQDSRHQR IRLPHLEAVV IGRGPETKIT DKKCSRQQVQ
    61  LKAECNKGYV KVKQVGVNPT SIDSVVIGKD QEVKLQPGQV LHMVNELYPY IVEFEEEAKN
   121  PGLETHRKRK RSGNSDSIER DAAQEAEAGT GLEPGSNSGQ CSVPLKKGKD APIKKESLGH
   181  WSQGLKISMQ DPKMQVYKDE QVVVIKDKYP KARYHWLVLP WTSISSLKAV AREHLELLKH
   241  MHTVGEKVIV DFAGSSKLRF RLGYHAIPSM SHVHLHVISQ DFDSPCLKNK KHWNSFNTEY
   301  FLESQAVIEM VQEAGRVTVR DGMPELLKLP LRCHECQQLL PSIPQLKEHL RKHWTQ

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against APTX 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
Intracellular
Secreted
No
Transmembrane segments
0
Mean surface accessibility (rSASA)
0.37
Highest tissue expression
15 nTPM

Expression across tissuesHPA

Tissue

  • liver: 15 nTPM
  • parathyroid gland: 11 nTPM
  • kidney: 11 nTPM
  • rectum: 11 nTPM
  • bone marrow: 10 nTPM
  • testis: 10 nTPM

Single-cell type

  • choroid plexus epithelial cells: 187 nCPM
  • ependymal cells: 125 nCPM
  • early spermatids: 105 nCPM
  • adrenal cortex cells: 98 nCPM
  • lactotrophs: 90 nCPM
  • neutrophils: 88 nCPM

Immune cell

  • NK-cell: 23 nTPM
  • non-classical monocyte: 22 nTPM
  • myeloid DC: 18 nTPM
  • T-reg: 17 nTPM
  • memory B-cell: 16 nTPM
  • naive B-cell: 16 nTPM

Brain region

  • hypothalamus: 6.4 nTPM
  • cerebral cortex: 6.3 nTPM
  • pons: 6 nTPM
  • white matter: 5.7 nTPM
  • medulla oblongata: 5.6 nTPM
  • cerebellum: 5.5 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about APTX.

Disease | AllUniProt

Conditions APTX is implicated in, by any mechanism.

  • Ataxia-oculomotor apraxia syndrome (AOA) MIM:208920

Disease | GeneticClinVar

40 pathogenic / likely-pathogenic of 343 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)
1.3
gnomAD pLI
0
gnomAD missense Z
-0.37
DepMap mean gene effect
-0.02
DepMap dependency class
none

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

InteractionsUniProt · HPA

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

APTX 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 APTX as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

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