Seroatlas · Human Serome Atlas

TOP3A

DNA topoisomerase 3-alpha

Also known as: TOP3, TOP3A_HUMAN, ZGRF7

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

Protein identityUniProt · HPA

UniProt accession
Q13472
Gene
TOP3A
Ensembl
ENSG00000177302
Chromosome
17
Canonical length
1001 aa
Protein class
Cancer-related genes, Disease related genes, Enzymes, Human disease related genes, Potential drug targets, Predicted intracellular proteins

OverviewNCBI Gene

This gene encodes a DNA topoisomerase, an enzyme that controls and alters the topologic states of DNA during transcription. This enzyme catalyzes the transient breaking and rejoining of a single strand of DNA which allows the strands to pass through one another, thus reducing the number of supercoils and altering the topology of DNA. This enzyme forms a complex with BLM which functions in the regulation of recombination in somatic cells. Alternative splicing results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Mar 2016]

Canonical amino-acid sequenceUniProt

1001 residues, UniProt reviewed canonical sequence.

>Q13472|TOP3A
     1  MIFPVARYAL RWLRRPEDRA FSRAAMEMAL RGVRKVLCVA EKNDAAKGIA DLLSNGRMRR
    61  REGLSKFNKI YEFDYHLYGQ NVTMVMTSVS GHLLAHDFQM QFRKWQSCNP LVLFEAEIEK
   121  YCPENFVDIK KTLERETRQC QALVIWTDCD REGENIGFEI IHVCKAVKPN LQVLRARFSE
   181  ITPHAVRTAC ENLTEPDQRV SDAVDVRQEL DLRIGAAFTR FQTLRLQRIF PEVLAEQLIS
   241  YGSCQFPTLG FVVERFKAIQ AFVPEIFHRI KVTHDHKDGI VEFNWKRHRL FNHTACLVLY
   301  QLCVEDPMAT VVEVRSKPKS KWRPQALDTV ELEKLASRKL RINAKETMRI AEKLYTQGYI
   361  SYPRTETNIF PRDLNLTVLV EQQTPDPRWG AFAQSILERG GPTPRNGNKS DQAHPPIHPT
   421  KYTNNLQGDE QRLYEFIVRH FLACCSQDAQ GQETTVEIDI AQERFVAHGL MILARNYLDV
   481  YPYDHWSDKI LPVYEQGSHF QPSTVEMVDG ETSPPKLLTE ADLIALMEKH GIGTDATHAE
   541  HIETIKARMY VGLTPDKRFL PGHLGMGLVE GYDSMGYEMS KPDLRAELEA DLKLICDGKK
   601  DKFVVLRQQV QKYKQVFIEA VAKAKKLDEA LAQYFGNGTE LAQQEDIYPA MPEPIRKCPQ
   661  CNKDMVLKTK KNGGFYLSCM GFPECRSAVW LPDSVLEASR DSSVCPVCQP HPVYRLKLKF
   721  KRGSLPPTMP LEFVCCIGGC DDTLREILDL RFSGGPPRAS QPSGRLQANQ SLNRMDNSQH
   781  PQPADSRQTG SSKALAQTLP PPTAAGESNS VTCNCGQEAV LLTVRKEGPN RGRQFFKCNG
   841  GSCNFFLWAD SPNPGAGGPP ALAYRPLGAS LGCPPGPGIH LGGFGNPGDG SGSGTSCLCS
   901  QPSVTRTVQK DGPNKGRQFH TCAKPREQQC GFFQWVDENT APGTSGAPSW TGDRGRTLES
   961  EARSKRPRAS SSDMGSTAKK PRKCSLCHQP GHTRPFCPQN R

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against TOP3A 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)
0.34
Highest tissue expression
6.4 nTPM

Expression across tissuesHPA

Tissue

  • cerebellum: 6.4 nTPM
  • liver: 6.2 nTPM
  • testis: 6.2 nTPM
  • skin: 5.8 nTPM
  • spleen: 5.8 nTPM
  • skeletal muscle: 5.5 nTPM

Single-cell type

  • choroid plexus epithelial cells: 32 nCPM
  • brain inhibitory neurons: 28 nCPM
  • brain excitatory neurons: 28 nCPM
  • renal collecting duct intercalated cells: 28 nCPM
  • other brain neurons: 25 nCPM
  • distal convoluted tubule cells: 24 nCPM

Immune cell

  • neutrophil: 4.1 nTPM
  • eosinophil: 3.4 nTPM
  • classical monocyte: 3 nTPM
  • intermediate monocyte: 2.7 nTPM
  • NK-cell: 2.2 nTPM
  • total PBMC: 2 nTPM

Brain region

  • cerebellum: 6.6 nTPM
  • choroid plexus: 4.8 nTPM
  • cerebral cortex: 4.4 nTPM
  • hypothalamus: 4.4 nTPM
  • white matter: 4.3 nTPM
  • basal ganglia: 4.2 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about TOP3A.

Disease | AllUniProt

Conditions TOP3A is implicated in, by any mechanism.

  • Microcephaly, growth restriction, and increased sister chromatid exchange 2 (MGRISCE2) MIM:618097
  • Progressive external ophthalmoplegia with mitochondrial DNA deletions, autosomal recessive 5 (PEOB5) MIM:618098

Disease | GeneticClinVar

37 pathogenic / likely-pathogenic of 514 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)
0.68
gnomAD pLI
0
gnomAD missense Z
1.31
DepMap mean gene effect
-1.18
DepMap dependency class
common

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 5% 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 TOP3A 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 TOP3A as an antibody target. Whether an autoantibody or antibody against TOP3A could matter depends on whether native TOP3A is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

TOP3A 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 TOP3A as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/TOP3A. 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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