id: Q09683
gene_symbol: mre11
locus_tag: SPAC13C5.07
taxon:
  id: NCBITaxon:284812
  label: Schizosaccharomyces pombe (strain 972 / ATCC 24843)
status: COMPLETE
description: Mre11 DNA endonuclease, exonuclease and meiotic-cell-cycle predictions are supported but
  less precise than established substrate-specific activities and meiotic repair annotations.
source_documents:
- genes/SCHPO/mre11/mre11-protnlm-source.xml
- genes/SCHPO/mre11/mre11-uniprot.txt
- genes/SCHPO/mre11/mre11-ai-review.yaml
predictions:
- source_method: ProtNLM2
  source_version: pre-release post-processed-2026_02_28k.xml
  predicted_term:
    id: GO:0004520
    label: DNA endonuclease activity
  predicted_term_type: GO_MF
  review:
    assessment: LSP
    confidence_score: 2
    summary: DNA endonuclease activity is supported by fission yeast nuclease-mutant experiments and conserved
      Mre11 biochemistry. GOA already includes single-stranded DNA endonuclease activity (GO:0000014),
      in addition to this exact broad term. The prediction loses substrate specificity relative to that
      established annotation. This biological overlap does not establish training-set membership.
    supported_by:
    - &id003
      reference_id: PMID:19139281
      supporting_text: This study demonstrates for the first time that Mre11 (Schizosaccharomyces pombe
        Rad32(Mre11)) nuclease activity is required for the removal of Rec12(Spo11).
    - &id001
      reference_id: PMID:9651580
      supporting_text: We have investigated the enzymatic activities of the purified proteins and found
        that Mre11 by itself has 3' to 5' exonuclease activity that is increased when Mre11 is in a complex
        with Rad50. Mre11 also exhibits endonuclease activity, as shown by the asymmetric opening of DNA
        hairpin loops.
    - &id002
      reference_id: PMID:22705791
      supporting_text: To understand the functional architecture of MRN, we determined the crystal structures
        of the Schizosaccharomyces pombe Mre11 dimeric catalytic domain alone and in complex with a fragment
        of Nbs1.
    - reference_id: PMID:9705271
      supporting_text: We show that the Rad50-Mre11-p95 complex possesses manganese-dependent single-stranded
        DNA endonuclease and 3' to 5' exonuclease activities.
  source_reference_id: file:SCHPO/mre11/mre11-protnlm-source.xml
- source_method: ProtNLM2
  source_version: pre-release post-processed-2026_02_28k.xml
  predicted_term:
    id: GO:0008296
    label: 3'-5'-DNA exonuclease activity
  predicted_term_type: GO_MF
  review:
    assessment: LSP
    confidence_score: 2
    summary: The conserved Mre11 nuclease domain supports 3′-to-5′ exonuclease chemistry, supported by
      purified-protein biochemistry and fission yeast catalytic-domain structure. GOA already records
      double-stranded DNA 3′-5′ DNA exonuclease activity (GO:0008311) by curated orthology transfer. The
      predicted term omits the substrate specificity of that established function. The net polarity of
      DNA-end resection does not refute the intrinsic exonuclease polarity.
    supported_by:
    - *id001
    - *id002
  source_reference_id: file:SCHPO/mre11/mre11-protnlm-source.xml
- source_method: ProtNLM2
  source_version: pre-release post-processed-2026_02_28k.xml
  predicted_term:
    id: GO:0051321
    label: meiotic cell cycle
  predicted_term_type: GO_BP
  review:
    assessment: LSP
    confidence_score: 2
    summary: Fission yeast rad32 mutants impair meiotic recombination, and Rad32 nuclease activity is
      required for removal of Rec12-linked ends. These experiments establish participation in the meiotic
      cell cycle. GOA already captures reciprocal meiotic recombination and double-strand break repair
      involved in meiotic recombination, which are more informative than the broad cell-cycle term. The
      prediction does not imply a general requirement for Rec12-dependent break formation.
    supported_by:
    - reference_id: PMID:7885834
      supporting_text: Pulsed field gel electrophoresis of DNA from irradiated cells indicates that the
        rad32 mutant, in comparison to wild type cells, has decreased ability to repair DNA double strand
        breaks. The mutant also undergoes decreased meiotic recombination and displays reduced stability
        of minichromosomes.
    - *id003
    - reference_id: PMID:15238514
      supporting_text: Meiotic DNA breakage in Schizosaccharomyces pombe did not require Rad50 or Rad32,
        although the homologs Rad50 and Mre11 are required in Saccharomyces cerevisiae; these proteins
        are required for meiotic DNA break repair in both yeasts.
  source_reference_id: file:SCHPO/mre11/mre11-protnlm-source.xml
references:
- id: PMID:19139281
  title: Ctp1CtIP and Rad32Mre11 nuclease activity are required for Rec12Spo11 removal, but Rec12Spo11
    removal is dispensable for other MRN-dependent meiotic functions.
- id: PMID:9651580
  title: The 3' to 5' exonuclease activity of Mre 11 facilitates repair of DNA double-strand breaks.
- id: PMID:22705791
  title: Structure of Mre11-Nbs1 complex yields insights into ataxia-telangiectasia-like disease mutations
    and DNA damage signaling.
- id: PMID:7885834
  title: 'Cloning and characterisation of the Schizosaccharomyces pombe rad32 gene: a gene required for
    repair of double strand breaks and recombination.'
- id: PMID:15238514
  title: Conserved and nonconserved proteins for meiotic DNA breakage and repair in yeasts.
- id: file:SCHPO/mre11/mre11-protnlm-source.xml
  title: Original pre-release ProtNLM2 XML entry for mre11
- id: PMID:9705271
  title: Nuclease activities in a complex of human recombination and DNA repair factors Rad50, Mre11,
    and p95.