id: M9NFR3
gene_symbol: CycA
taxon:
  id: NCBITaxon:7227
  label: Drosophila melanogaster
status: COMPLETE
description: Both the CDK-regulator and mitotic-transition predictions are supported by characterized
  cyclin A biology and complete retention of the cyclin domain.
source_documents:
- genes/DROME/CycA/CycA-protnlm-source.json
- genes/DROME/CycA/CycA-bioinformatics/RESULTS.md
predictions:
- source_method: ProtNLM2
  source_version: UniProt API snapshot 2026-09-08
  source_reference_id: file:DROME/CycA/CycA-protnlm-source.json
  predicted_term:
    id: GO:0016538
    label: cyclin-dependent protein serine/threonine kinase regulator activity
  predicted_term_type: GO_MF
  review:
    assessment: CNN
    confidence_score: 2
    summary: The PC isoform preserves the complete cyclin domain of characterized Drosophila CycA. Primary
      work on the CycA–Cdk1 system demonstrates control of CDK substrate recognition through the cyclin
      hydrophobic patch. The one-residue N-terminal isoform difference lies outside that domain, supporting
      the broad regulator transfer. Sparse accession-level GOA does not make this established fly function
      biologically novel, so CNN applies; actual inclusion in the model training set is not established.
    supported_by:
    - reference_id: PMID:17431409
      supporting_text: 'We propose that binding

        of Frs to cyclins blocks the hydrophobic patch to interfere with Cdk1 substrate

        recognition.'
    - &id001
      reference_id: file:DROME/CycA/CycA-bioinformatics/RESULTS.md
      supporting_text: The annotated cyclin domain 206–332 is fully retained and maps to target 205–331.
- source_method: ProtNLM2
  source_version: UniProt API snapshot 2026-09-08
  source_reference_id: file:DROME/CycA/CycA-protnlm-source.json
  predicted_term:
    id: GO:0044772
    label: mitotic cell cycle phase transition
  predicted_term_type: GO_BP
  review:
    assessment: CNN
    confidence_score: 2
    summary: Fly cyclin A is required for continued mitotic divisions and undergoes cell-cycle-dependent
      accumulation and prophase relocalization. PC retains the complete cyclin domain, supporting the
      conserved mitotic-transition role. The original target GOA contains broader terms, but the relevant
      same-gene biology is already described in the literature. The prediction is therefore CNN; actual
      inclusion in the model training set is not established.
    supported_by:
    - reference_id: PMID:2564316
      supporting_text: 'a functional cyclin A gene was required for continued division

        after exhaustion of maternally contributed cyclin A.'
    - reference_id: PMID:2564316
      supporting_text: 'cyclin A accumulates in the interphase cytoplasm of cellularized embryos, but

        relocates to the nuclear region early in prophase'
    - *id001
references:
- id: PMID:17431409
  title: The Drosophila mitotic inhibitor Frühstart specifically binds to the hydrophobic patch of cyclins.
  findings: []
- id: file:DROME/CycA/CycA-bioinformatics/RESULTS.md
  title: RESULTS.md
  findings: []
- id: PMID:2564316
  title: Expression and function of Drosophila cyclin A during embryonic cell cycle progression.
  findings: []