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rapid axopodial contraction

traitmech:000682 · CLASS · PROPOSED

A physiological phenotype in which a microbial cell rapidly shortens its microtubule-supported axopodia in response to stimulation or prey uptake.

Trait evidence (2)

  • DOI:10.2108/zsj.20.1367
    Axopodial contraction of the centrohelid heliozoon Raphidiophrys contractilis was induced by mechanical or electrical stimulation.

    Khan et al. (2003), scientific Abstract, directly retrieved from Europe PMC for PMID:14624035 at https://www.ebi.ac.uk/europepmc/webservices/rest/search?query=EXT_ID:14624035&resultType=core&format=json. Abstract-only access; full Methods and figures were not inspected. The study reports contraction faster than 3.0 mm/sec, followed by re-elongation initially about 0.30 microm/sec, and a microtubule bundle in each axopodium. Extracellular calcium dependence is restricted to this stimulation assay, not a universal defining threshold. Failure to detect other filaments with the reported fixation method does not prove their biological absence. Source taxon spelling is retained; natural culture provenance and current taxonomic identity are not established here.

  • DOI:10.1111/j.1550-7408.2001.tb00187.x
    Upon food uptake, the tubules shorten and transform into a mass of small granules when rapid axopodial contraction occurs

    Kinoshita et al. (2001), scientific Abstract, directly read at https://pubmed.ncbi.nlm.nih.gov/11596916/ and cross-checked against Europe PMC's scientific abstract. Abstract-only access; full Methods and figures were not inspected. The study concerns Actinophrys sol. Contractile-tubule shortening and granulation accompany the food-uptake response; the authors suggest, rather than prove, a causal role. Cold and colchicine both induce microtubule disassembly, but only cold induces tubule granulation in the reported comparison. Neither intervention alone defines the natural rapid-contraction phenotype. No protein identity, effect size or strain provenance is inferred.

Provenance

Identifier source
TraitMech local identifier
Definition source
DOI:10.2108/zsj.20.1367

Parent traits (1)

kg-microbe context

No kg-microbe node embedding matched this record in the 2026-04-25 deepwalk.

Discussions and Knowledge Gaps (2)

Open questions attached to this trait. Seeded by just knowledge-gap-scan and curated; see the corpus-wide index.

Resolve a closer cellular-contractility parent and assay boundaries.

CURATION TODO OPEN axopodial-contraction-scope-and-parent · raised by codex · 2026-10-08

Not yet attached to a section of this record — a curator sets attaches_to (e.g. causal_graphs#some_edge) so the gap shows beside the mechanism it concerns.

Phenotype METPO:1000059 is a broad parent. Existing motile METPO:1000702 is curated around organismal locomotion; rapid shortening of a cellular projection does not alone establish whole-cell locomotion. Keep axopodial contraction separate from ordinary pseudopod extension, re-elongation, slow structural loss, stalk or whole-cell contraction, and drug-induced microtubule disassembly. The reported speed is an observation, not a universal cutoff. No exact synonyms, xrefs, SSSOM equivalences or organism-level disjointness are asserted. Closer hierarchy and comparable time-resolved assays remain open.

Resolve culture provenance and taxon-specific contraction mechanisms.

KNOWLEDGE GAP OPEN axopodial-contraction-provenance-and-mechanism · raised by codex · 2026-10-08

Not yet attached to a section of this record — a curator sets attaches_to (e.g. causal_graphs#some_edge) so the gap shows beside the mechanism it concerns.

The directly read abstracts do not establish natural strain provenance or accession-level identities for canonical examples. Retain the source-named organisms as qualified evidence, not universal taxon assertions; resolve their current taxonomy and original culture descriptions before adding exemplars. Calcium dependence, microtubule disassembly and contractile-tubule observations must not be combined into one universal heliozoan mechanism. A protein-resolved graph requires direct perturbation evidence and taxon-paired accessions. Mechanism is deferred, not claimed absent; tubulin sequence features alone do not establish this response.

Curation history

  1. · MINTED_TRAITMECH_ID · codex

    Added rapid axopodial contraction with two primary DOI sources and contiguous scientific-abstract snippets checked directly. Ignored-and-hidden main/worktree/open-PR checks support 000682 and v558 block 1063500-1063599. Kept natural culture provenance, closer hierarchy and protein mechanism unresolved. Distinguished rapid response from locomotion and induced structural breakdown. Existing records unchanged. Timestamp is observed UTC.

Recorded curation sessions

  • · codex
    • CREATE — Add evidence-backed rapid axopodial contraction

      Added traitmech:000682 with two primary DOI scientific-abstract snippets, broad phenotype parent and proposal v558. Deferred natural culture exemplars, closer hierarchy and protein mechanism; no existing records changed.

    Read this curation session