Seroatlas · Human Serome Atlas

TOP1MT

DNA topoisomerase I, mitochondrial

Also known as: TOP1M_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q969P6
Gene
TOP1MT
Ensembl
ENSG00000184428
Chromosome
8
Canonical length
601 aa
Protein class
Enzymes, FDA approved drug targets, Predicted intracellular proteins
Subcellular location
Mitochondria

OverviewNCBI Gene

This gene encodes a mitochondrial DNA topoisomerase that plays a role in the modification of DNA topology. The encoded protein is a type IB topoisomerase and catalyzes the transient breaking and rejoining of DNA to relieve tension and DNA supercoiling generated in the mitochondrial genome during replication and transcription. Alternatively spliced transcript variants encoding multiple isoforms have been observed for this gene. [provided by RefSeq, May 2012]

Canonical amino-acid sequenceUniProt

601 residues, UniProt reviewed canonical sequence.

>Q969P6|TOP1MT
     1  MRVVRLLRLR AALTLLGEVP RRPASRGVPG SRRTQKGSGA RWEKEKHEDG VKWRQLEHKG
    61  PYFAPPYEPL PDGVRFFYEG RPVRLSVAAE EVATFYGRML DHEYTTKEVF RKNFFNDWRK
   121  EMAVEEREVI KSLDKCDFTE IHRYFVDKAA ARKVLSREEK QKLKEEAEKL QQEFGYCILD
   181  GHQEKIGNFK IEPPGLFRGR GDHPKMGMLK RRITPEDVVI NCSRDSKIPE PPAGHQWKEV
   241  RSDNTVTWLA AWTESVQNSI KYIMLNPCSK LKGETAWQKF ETARRLRGFV DEIRSQYRAD
   301  WKSREMKTRQ RAVALYFIDK LALRAGNEKE DGEAADTVGC CSLRVEHVQL HPEADGCQHV
   361  VEFDFLGKDC IRYYNRVPVE KPVYKNLQLF MENKDPRDDL FDRLTTTSLN KHLQELMDGL
   421  TAKVFRTYNA SITLQEQLRA LTRAEDSIAA KILSYNRANR VVAILCNHQR ATPSTFEKSM
   481  QNLQTKIQAK KEQVAEARAE LRRARAEHKA QGDGKSRSVL EKKRRLLEKL QEQLAQLSVQ
   541  ATDKEENKQV ALGTSKLNYL DPRISIAWCK RFRVPVEKIY SKTQRERFAW ALAMAGEDFE
   601  F

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against TOP1MT 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)
0.31
Highest tissue expression
46 nTPM

Expression across tissuesHPA

Tissue

  • bone marrow: 46 nTPM
  • liver: 29 nTPM
  • ovary: 27 nTPM
  • testis: 22 nTPM
  • cervix: 22 nTPM
  • skin: 22 nTPM

Single-cell type

  • differentiating spermatogonia: 60 nCPM
  • late primary spermatocytes: 60 nCPM
  • esophageal basal cells: 54 nCPM
  • undifferentiated spermatogonia: 52 nCPM
  • oocytes: 41 nCPM
  • erythrocyte progenitors: 38 nCPM

Immune cell

  • myeloid DC: 35 nTPM
  • basophil: 31 nTPM
  • plasmacytoid DC: 31 nTPM
  • memory B-cell: 29 nTPM
  • naive CD4 T-cell: 24 nTPM
  • naive CD8 T-cell: 19 nTPM

Brain region

  • cerebral cortex: 25 nTPM
  • basal ganglia: 23 nTPM
  • pons: 22 nTPM
  • amygdala: 21 nTPM
  • white matter: 21 nTPM
  • hippocampal formation: 20 nTPM

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)
1.68
gnomAD pLI
0
gnomAD missense Z
-0.11
DepMap mean gene effect
-0.02
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 15% 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

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads TOP1MT as an antibody target. Whether an autoantibody or antibody against TOP1MT could matter depends on whether native TOP1MT is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

TOP1MT 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 TOP1MT as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/TOP1MT. 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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