identifier: traitmech:000685
label: toxicyst discharge
definition: A physiological phenotype in which a microbial cell releases material
  from toxicysts, its offensive extrusomes, to the cell exterior.
definition_source: DOI:10.1111/jeu.12106
trait_category: PHYSIOLOGY
term_kind: CLASS
mapping_status: PROPOSED
parent_traits:
- METPO:1000059
evidence:
- reference: DOI:10.1111/jeu.12106
  snippet: we isolated the discharge of the toxicysts from living cells
  notes: 'PMID:24512001. Scientific Abstract read directly in PubMed and Europe PMC
    (EXT_ID:24512001 AND SRC:MED); source, title and DOI agree. Coleps hirtus discharge
    was collected and tested against other ciliates. This supports extracellular release
    from living cells, not merely possession of an organelle or toxicity of a whole-cell
    extract. Abstract-only access: full Methods and figures were not inspected; the
    institutional postprint at https://hdl.handle.net/11393/192287 is access-restricted.
    The reported chemical mixture is not a universal toxicyst cargo.'
- reference: DOI:10.1007/BF01279249
  snippet: Injection of Ca2+ evoked discharge of toxicysts, if the site of the injection
    was the periphery region of the proboscis.
  notes: Scientific Summary read directly on the publisher page; Ca2+ represents its
    rendered superscript charge. Methods, Results and captions also read in the author-upload
    full-text transcript at https://www.researchgate.net/publication/227062328_Ca2_triggers_toxicyst_discharge_in_Didinium_nasutum.
    Figures were not visually inspected. Didinium nasutum pressure injection near
    the proboscis periphery produced discharge in 8/11 cells versus 1/11 calcium-free
    controls; cell-body and central-proboscis injections did not. Iontophoretic injection
    caused damage and cytoplasm outflow, motivating pressure injection. These are
    assay-specific observations, not a universal calcium requirement or proof of a
    particular fusion protein. No PMID was resolved by the exact DOI query.
- reference: DOI:10.1186/s12915-024-01904-2
  snippet: However, our understanding of the genetic processes and specific toxins
    involved in toxicyst formation and discharge is still limited.
  notes: 'PMID:38715037, PMC11077807. Scientific Abstract, Background, morphology
    Results, Discussion and collection/TEM Methods read in primary HTML/fullTextXML.
    Figure 1 was visually inspected: A-C are drawings, whereas D-F are TEM images
    of fixed Litonotus. The drawing of discharge is not direct imaging of release.
    Sequence and expression associations motivate toxin/transport hypotheses, not
    experimentally resolved discharge mechanisms. Genomics supplements were not inspected
    and are not used for accessions, prevalence or functional assignments.'
discussions:
- discussion_id: toxicyst-discharge-scope-and-parent
  prompt: Resolve the exocytosis hierarchy without equating all extrusome types.
  kind: CURATION_TODO
  status: OPEN
  rationale: Parent phenotype METPO:1000059 is conservative. The 2024 Background describes
    telescopic discharge and/or membrane fusion; its Discussion reports fusion observations.
    These statements do not establish that every toxicyst-discharge phenotype satisfies
    the fusion-pore definition of exocytosis traitmech:000637. That placement remains
    unresolved, not excluded. Mere toxicyst possession, docking, predation, prey injury
    or cell lysis does not alone establish this trait. Preserve the organelle-specific
    scope rather than equating mucocyst discharge traitmech:000684, trichocyst discharge
    traitmech:000683, pexicysts or haptocysts. Historical type-I/II terminology needs
    reconciliation before synonym or hierarchy expansion. No exact synonyms, xrefs
    or organism-level disjointness are asserted. Prey killing and complete emptying
    are not universal defining requirements.
  posed_by: codex
  posed_date: '2026-10-08'
- discussion_id: toxicyst-discharge-provenance-and-mechanism
  prompt: Resolve experimental culture provenance and protein-level mechanisms.
  kind: KNOWLEDGE_GAP
  status: OPEN
  rationale: Natural provenance and strain-level taxonomy of the positive experimental
    cultures remain unchecked; no canonical examples are assigned. Wild-collected
    genomic material is not by itself a positive discharge assay for that isolate.
    Gene-family expansion, expression and predicted toxin annotations alone do not
    establish toxicyst discharge or a causal protein. A future graph needs source-specific
    perturbations and taxon-paired accessions, distinguishing assembly, triggering,
    extrusion and toxin action. Mechanism is deferred, not claimed absent. Do not
    transfer a calcium threshold, cargo chemistry or ecological function between species
    without evidence.
  posed_by: codex
  posed_date: '2026-10-08'
curation_history:
- timestamp: '2026-10-08T18:21:12Z'
  curator: codex
  action: MINTED_TRAITMECH_ID
  changes: Added toxicyst discharge with three primary DOI sources and directly checked
    abstract/Summary snippets. Ignored-and-hidden main/worktree/open-PR checks support
    000685 and v561 block 1063800-1063899. Retained phenotype parent while making
    the exocytosis placement explicit and unresolved. Distinguished discharge from
    damage, organelle possession and sequence-based predictions. Existing records
    unchanged. Timestamp is observed UTC.
  llm_assisted: true