Seroatlas · Human Serome Atlas

TOP1

DNA topoisomerase 1

Also known as: TOP1_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
P11387
Gene
TOP1
Ensembl
ENSG00000198900
Chromosome
20
Canonical length
765 aa
Protein class
Cancer-related genes, Disease related genes, Enzymes, FDA approved drug targets, Predicted intracellular proteins
Subcellular location
Nucleoplasm,Nucleoli fibrillar center

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 altering the topology of DNA. This gene is localized to chromosome 20 and has pseudogenes which reside on chromosomes 1 and 22. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

765 residues, UniProt reviewed canonical sequence.

>P11387|TOP1
     1  MSGDHLHNDS QIEADFRLND SHKHKDKHKD REHRHKEHKK EKDREKSKHS NSEHKDSEKK
    61  HKEKEKTKHK DGSSEKHKDK HKDRDKEKRK EEKVRASGDA KIKKEKENGF SSPPQIKDEP
   121  EDDGYFVPPK EDIKPLKRPR DEDDADYKPK KIKTEDTKKE KKRKLEEEED GKLKKPKNKD
   181  KDKKVPEPDN KKKKPKKEEE QKWKWWEEER YPEGIKWKFL EHKGPVFAPP YEPLPENVKF
   241  YYDGKVMKLS PKAEEVATFF AKMLDHEYTT KEIFRKNFFK DWRKEMTNEE KNIITNLSKC
   301  DFTQMSQYFK AQTEARKQMS KEEKLKIKEE NEKLLKEYGF CIMDNHKERI ANFKIEPPGL
   361  FRGRGNHPKM GMLKRRIMPE DIIINCSKDA KVPSPPPGHK WKEVRHDNKV TWLVSWTENI
   421  QGSIKYIMLN PSSRIKGEKD WQKYETARRL KKCVDKIRNQ YREDWKSKEM KVRQRAVALY
   481  FIDKLALRAG NEKEEGETAD TVGCCSLRVE HINLHPELDG QEYVVEFDFL GKDSIRYYNK
   541  VPVEKRVFKN LQLFMENKQP EDDLFDRLNT GILNKHLQDL MEGLTAKVFR TYNASITLQQ
   601  QLKELTAPDE NIPAKILSYN RANRAVAILC NHQRAPPKTF EKSMMNLQTK IDAKKEQLAD
   661  ARRDLKSAKA DAKVMKDAKT KKVVESKKKA VQRLEEQLMK LEVQATDREE NKQIALGTSK
   721  LNYLDPRITV AWCKKWGVPI EKIYNKTQRE KFAWAIDMAD EDYEF

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against TOP1 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)
0.4
Highest tissue expression
71 nTPM

Expression across tissuesHPA

Tissue

  • bone marrow: 71 nTPM
  • tonsil: 57 nTPM
  • lymph node: 56 nTPM
  • thymus: 55 nTPM
  • placenta: 47 nTPM
  • appendix: 47 nTPM

Single-cell type

  • syncytiotrophoblasts: 1,442 nCPM
  • alveolar cells type 2: 1,250 nCPM
  • neutrophils: 1,184 nCPM
  • transitional alveolar cells: 883 nCPM
  • ocular epithelial cells: 736 nCPM
  • esophageal apical cells: 694 nCPM

Immune cell

  • neutrophil: 19 nTPM
  • plasmacytoid DC: 19 nTPM
  • eosinophil: 17 nTPM
  • non-classical monocyte: 13 nTPM
  • basophil: 13 nTPM
  • memory B-cell: 11 nTPM

Brain region

  • choroid plexus: 39 nTPM
  • cerebellum: 31 nTPM
  • cerebral cortex: 28 nTPM
  • thalamus: 26 nTPM
  • hypothalamus: 25 nTPM
  • white matter: 25 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about TOP1.

Disease | GeneticClinVar

1 pathogenic / likely-pathogenic of 78 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

  • DNA topoisomerase I, camptothecin-resistant

Disease | ImmuneIEDB

Conditions an epitope on TOP1 was assayed in.

Disease | AutoantibodyPubMed

Conditions in which antibodies against TOP1 are reported. Each links to that disease's full target list.

Showing 20 of 27 — disease pages carrying at least 10 antigens.

ReferencesPubMed · IEDB

Publications for TOP1 from three distinct lines of evidence, kept separate because they answer different questions: whether antibodies are directed at the protein, whether a B-cell epitope has been mapped on it, and whether a T-cell epitope has. Each is labelled with its source.

Reference: AutoantibodyPubMed

485 publications

Show 20 more of 485 total

Reference: B cellIEDB

2 publications

Reference: T cellIEDB

5 publications

Sources: PubMed — antigen-level antibody evidence from a custom retrieval. Records matching a controlled set of autoantibody terms (the MeSH descriptors Autoantibodies and Autoantigens, with title and abstract term variants) were obtained through NCBI E-utilities, and their titles and abstracts parsed for constructions that direct an antibody at a named protein rather than for co-occurrence. Captured names were resolved against UniProt nomenclature and each antigen adjudicated individually against the source text. IEDB — curated epitope assays from the Immune Epitope Database (Vita et al., Nucleic Acids Research 2019). Bibliographic records from PubMed and MeSH, U.S. National Library of Medicine; citation metrics from NIH iCite (Hutchins et al., PLoS Biology 2016). Titles link to PubMed; abstracts are not reproduced here. The NLM does not endorse this analysis.

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)
0.06
gnomAD pLI
1
gnomAD missense Z
4.47
DepMap mean gene effect
-1
DepMap dependency class
common

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 9% 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 TOP1 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 TOP1 as an antibody target. Whether an autoantibody or antibody against TOP1 could matter depends on whether native TOP1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

TOP1 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 TOP1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/TOP1. 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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