identifier: traitmech:000615 label: tetrapolar mating system definition: A fungal mating phenotype in which compatibility between partners is governed by two independently segregating mating-type factors and requires different specificities at both factors. definition_source: DOI:10.1371/journal.pgen.1002528 trait_category: PHYSIOLOGY term_kind: CLASS mapping_status: PROPOSED parent_traits: - METPO:1000059 evidence: - reference: DOI:10.1371/journal.pgen.1002528 snippet: None of these MAT recombinant progeny mated with either parent, further confirming that C. amylolentus possesses a tetrapolar mating system notes: 'Findley et al. (2012), PMID:22359516, PMC3280970. Exact Results s2g clause, not an abstract quote. The preceding sentences report interfertility of complementary recombinants; parent sterility alone is insufficient. Introduction defines the two unlinked factors and differences at both. Actual Figures 8/9 were inspected: sexual structures and the mating matrix support the functional phenotype. Figure 9A is a conceptual model, not an observed equal-ratio result. Results s2b/s2e, direct prose of s2f/s2g and Methods s4a/s4m were read. Mixed F1 progeny include blastospores; frequent infertility and biased mating types make this a modified tetrapolar cycle. Complete Text S1 was text-extracted, not page-rendered: filamentation is not successful mating. Its description of F1S2 #16 as sterile must not override s2g''s successful crosses with some partners. Tables 1/2, other figures and other supplements remain uninspected. Physical MAT separation alone in T. wingfieldii does not establish its reproductive phenotype.' - reference: DOI:10.1534/genetics.115.177717 snippet: independent assortment of MAT alleles was observed in the meiotic progeny of a test cross. notes: Maia et al. (2015), PMID:26178967, PMC4566278. Exact scientific abstract clause, directly retrieved from Europe PMC core metadata and checked against NCBI efetch front matter. Leucosporidium scottii has physically unlinked HD and P/R regions; the reported meiotic segregation supports functional tetrapolarity independently of sequence annotation. Natural population linkage disequilibrium does not contradict the test-cross result. The abstract reports fertile progeny of four mating types but approximately two thirds nonhaploid; do not impose universal haploidy or equal ratios. Full-text XML/PDF endpoints failed with HTTP 500/403 and NCBI returned no body. Methods, figures, supplements and natural strain provenance remain uninspected; no canonical example is inferred. canonical_examples: - taxon_id: NCBITaxon:104669 taxon_label: Cryptococcus amylolentus reference: DOI:10.1371/journal.pgen.1002528 note: 'Qualified to the CBS6039 x CBS6273 cross, not every strain or laboratory-derived progeny. Natural provenance: Methods Strains and media at https://journals.plos.org/plosgenetics/article?id=10.1371/journal.pgen.1002528 reports both isolates from insect frass in South Africa. Mating used V8 pH 5 in the dark at 24 C; actual Figure 8 shows two-week sexual structures and Figure 9 compares complementary mating combinations. Recombinant fertility, not hyphae alone, supports the modified tetrapolar classification. NCBI taxonomy 104669 resolves to this species on 2026-10-05.' discussions: - discussion_id: tetrapolar-mating-scope-and-hierarchy prompt: Keep mating compatibility separate from partner dependence and MAT inventory. kind: CURATION_TODO status: OPEN rationale: This is a functional compatibility phenotype, not possession of two loci or exactly four mating types throughout a species. Factors can be multiallelic; different specificities are necessary, not a guarantee of fertile progeny in every cross. Findley describes the observed C. amylolentus cycle as heterothallic, but that example does not make the broader compatibility axis equivalent to obligatory separate-partner dependence in traitmech:000610. The latter already separates nuclear recognition from organism-level self-fertility. Use released phenotype METPO:1000059 in both record and proposal rather than infer universal self-sterility. Do not assert disjointness with homothallism, fixed segregation ratios, universal A/B naming or identical recognition architectures. Resolve bifactorial terminology and external mappings before adding synonyms or xrefs. PHYSIOLOGY is a filesystem category, not a narrower ontology parent. posed_by: codex posed_date: '2026-10-05' - discussion_id: tetrapolar-mating-mechanism-and-readouts prompt: Resolve native mechanisms and unread experiments before extending the graph. kind: CURATION_TODO status: OPEN rationale: Complete the unread Maia full text and Findley tables and supplements before finer mechanistic or strain claims. Distinguish MAT-locus separation, genetic segregation, compatibility, filamentation and fertile sexual progeny. An unsuccessful cross alone does not establish trait absence; source-specific sterility can be relative to particular partners. Resolve native protein accessions and experimentally tested dependencies before causal edges. No NONMECHANISTIC graph is used to bypass protein grounding. Manual full-text matches do not replace the abstract resolver's actual verdict. posed_by: codex posed_date: '2026-10-05' curation_history: - timestamp: '2026-10-05T07:16:00Z' curator: codex action: MINTED_TRAITMECH_ID changes: Added tetrapolar mating system with two independent DOI-backed sources and verbatim snippets, a qualified natural CBS6039 x CBS6273 example and verified NCBI taxonomy. Kept mating evidence distinct from MAT sequence inventory, universal fertility and partner dependence. Ignored-and-hidden novelty and allocation searches found no exact record or ID collision. Reserved METPO:1056900 in v492 under released phenotype. Deferred lexical mappings, protein mechanisms and explicitly unread source material. llm_assisted: true