id: Q0E9F2
gene_symbol: sns
taxon:
  id: NCBITaxon:7227
  label: Drosophila melanogaster
status: COMPLETE
description: Sns has established gene-level developmental roles, but the selected isoform B contains an
  extra 63-residue insertion with a predicted membrane-spanning segment. Gene-level Sns-dependent muscle
  and tissue morphogenesis is strongly supported. Membrane association is supported by the retained hydrophobic
  regions and direct Sns cell-surface localization.
source_documents:
- genes/DROME/sns/sns-predictions-source.json
- genes/DROME/sns/sns-uniprot-source.json
references:
- id: PMID:10859168
  title: Drosophila SNS, a member of the immunoglobulin superfamily that is essential for myoblast fusion.
  findings: []
  full_text_unavailable: true
- id: PMID:20599904
  title: Preferential adhesion maintains separation of ommatidia in the Drosophila eye.
  findings: []
  full_text_unavailable: false
- id: file:DROME/sns/sns-bioinformatics/RESULTS.md
  title: DROME/sns/sns-bioinformatics/RESULTS.md
  findings: []
predictions:
- source_method: ProtNLM2
  source_version: UniProt API snapshot 2026-09-08
  source_reference_id: file:DROME/sns/sns-predictions-source.json
  predicted_term:
    id: GO:0030154
    label: cell differentiation
  predicted_term_type: GO_BP
  review:
    assessment: UNC
    confidence_score: 1
    summary: Sns has established gene-level developmental roles, but the selected isoform B contains an
      extra 63-residue insertion with a predicted membrane-spanning segment. All shared residues are conserved,
      yet an additional membrane crossing could change presentation of the signaling tail required in
      fusion and differentiation. The accessible experiments do not resolve this topology or establish
      function of this exact longer form. Thus the prediction remains uncertain for the selected sequence,
      without disputing Sns gene-level differentiation biology.
    supported_by:
    - &id001
      reference_id: PMID:10859168
      supporting_text: The Drosophila sticks-and-stones (sns) locus was identified on the basis of its
        mutant phenotype, the complete absence of body wall muscles and corresponding presence of unfused
        myoblasts.
    - &id002
      reference_id: file:DROME/sns/sns-bioinformatics/RESULTS.md
      supporting_text: The sole difference is a 63-residue insertion at the reference 1059/1060 junction,
        corresponding to target 1060–1122.
    - &id003
      reference_id: file:DROME/sns/sns-bioinformatics/RESULTS.md
      supporting_text: The selected record predicts transmembrane segments 1089–1112 (within the insertion)
        and 1141–1166 (in the shared sequence).
- source_method: ProtNLM2
  source_version: UniProt API snapshot 2026-09-08
  source_reference_id: file:DROME/sns/sns-predictions-source.json
  predicted_term:
    id: GO:0009653
    label: anatomical structure morphogenesis
  predicted_term_type: GO_BP
  review:
    assessment: UNC
    confidence_score: 1
    summary: Gene-level Sns-dependent muscle and tissue morphogenesis is strongly supported. The exact
      selected isoform has a specific extra hydrophobic insertion that could alter the membrane topology
      required to couple extracellular adhesion to intracellular signaling. Its consequence is untested,
      so the morphology claim is not refuted but remains uncertain for this sequence. Mere agreement with
      the existing broad automated annotation would not resolve that issue.
    supported_by:
    - *id001
    - reference_id: PMID:20599904
      supporting_text: These results strongly suggest expression of Hbs and Sns is sufficient to render
        ommatidia less adhesive to other ommatidia than to IOCs.
    - *id002
    - *id003
- source_method: ProtNLM2
  source_version: UniProt API snapshot 2026-09-08
  source_reference_id: file:DROME/sns/sns-predictions-source.json
  predicted_term:
    id: GO:0016020
    label: membrane
  predicted_term_type: GO_CC
  review:
    assessment: LSP
    confidence_score: 2
    summary: Membrane association is supported by the retained hydrophobic regions and direct Sns cell-surface
      localization. The extra hydrophobic insertion raises signaling-topology questions but does not undermine
      membrane association itself. The prediction is broader than the existing plasma-membrane and nephrocyte-diaphragm
      annotations.
    supported_by:
    - reference_id: PMID:10859168
      supporting_text: SNS is enriched at the membrane and clusters at discrete sites, coincident with
        the occurrence of myoblast fusion.
    - *id003