Seroatlas · Human Serome Atlas

ATXN3

Ataxin-3

Also known as: ATX3, ATX3_HUMAN, JOS, MJD, SCA3

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

Protein identityUniProt · HPA

UniProt accession
P54252
Gene
ATXN3
Ensembl
ENSG00000066427
Chromosome
14
Canonical length
361 aa
Protein class
Disease related genes, Enzymes, Human disease related genes, Plasma proteins, Potential drug targets, Predicted intracellular proteins, Predicted membrane proteins
Subcellular location
Nucleoplasm,Nucleoli,Plasma membrane

OverviewNCBI Gene

Machado-Joseph disease, also known as spinocerebellar ataxia-3, is an autosomal dominant neurologic disorder. The protein encoded by this gene contains (CAG)n repeats in the coding region, and the expansion of these repeats from the normal 12-44 to 52-86 is one cause of Machado-Joseph disease. There is a negative correlation between the age of onset and CAG repeat numbers. Alternatively spliced transcript variants encoding different isoforms have been described for this gene. [provided by RefSeq, Jul 2016]

Canonical amino-acid sequenceUniProt

361 residues, UniProt reviewed canonical sequence.

>P54252|ATXN3
     1  MESIFHEKQE GSLCAQHCLN NLLQGEYFSP VELSSIAHQL DEEERMRMAE GGVTSEDYRT
    61  FLQQPSGNMD DSGFFSIQVI SNALKVWGLE LILFNSPEYQ RLRIDPINER SFICNYKEHW
   121  FTVRKLGKQW FNLNSLLTGP ELISDTYLAL FLAQLQQEGY SIFVVKGDLP DCEADQLLQM
   181  IRVQQMHRPK LIGEELAQLK EQRVHKTDLE RVLEANDGSG MLDEDEEDLQ RALALSRQEI
   241  DMEDEEADLR RAIQLSMQGS SRNISQDMTQ TSGTNLTSEE LRKRREAYFE KQQQKQQQQQ
   301  QQQQQGDLSG QSSHPCERPA TSSGALGSDL GDAMSEEDML QAAVTMSLET VRNDLKTEGK
   361  K

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against ATXN3 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
0
Mean surface accessibility (rSASA)
0.42
Highest tissue expression
12 nTPM

Expression across tissuesHPA

Tissue

  • skin: 12 nTPM
  • bone marrow: 9.3 nTPM
  • adipose tissue: 7 nTPM
  • esophagus: 6.9 nTPM
  • thymus: 6.5 nTPM
  • tonsil: 6.5 nTPM

Single-cell type

  • fibro-adipogenic progenitors: 199 nCPM
  • lymphatic endothelial cells: 171 nCPM
  • leydig cells: 151 nCPM
  • sertoli cells: 143 nCPM
  • peritubular myoid cells: 131 nCPM
  • lactotrophs: 127 nCPM

Immune cell

  • non-classical monocyte: 19 nTPM
  • intermediate monocyte: 15 nTPM
  • myeloid DC: 14 nTPM
  • classical monocyte: 13 nTPM
  • neutrophil: 11 nTPM
  • eosinophil: 9.9 nTPM

Brain region

  • pons: 18 nTPM
  • midbrain: 17 nTPM
  • medulla oblongata: 16 nTPM
  • cerebellum: 15 nTPM
  • hypothalamus: 15 nTPM
  • white matter: 15 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about ATXN3.

Disease | AllUniProt

Conditions ATXN3 is implicated in, by any mechanism.

Disease | GeneticClinVar

3 pathogenic / likely-pathogenic of 109 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)
0.49
gnomAD pLI
0.11
gnomAD missense Z
1.35
DepMap mean gene effect
0.04
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 ATXN3 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 ATXN3 as an antibody target. Whether an autoantibody or antibody against ATXN3 could matter depends on whether native ATXN3 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

ATXN3 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 ATXN3 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/ATXN3. 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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