dinoflagellate sulcal notch

GO:0097618 · Other · Subcellular region · Proposed

A dinoflagellate sulcus that extends all the way to the posterior end of the cell (also known as antapex). The presence of a sulcal notch makes the dinoflagellate hypocone appear bilobed. [GO:0097618]

Synonyms: dinoflagellate sulcus notch; sulcal notch

UniProt location names: UniProt Consortium, CC BY 4.0. Reference label and route sources.

Taxonomic distribution

NCBITaxon:2864 Dinophyceae — VARIABLE: GO:0097618 defines the sulcal notch as a dinoflagellate sulcus that reaches the posterior antapex and can make the hypocone appear bilobed. [GO:0097618]

Mechanism graphs

Sulcal-notch sulcus topology (FUNCTION)

The dinoflagellate sulcal notch is a specialized sulcus that extends to the posterior antapex and can make the hypocone appear bilobed.

Subject	Predicate	Object	Evidence
dinoflagellate sulcal notch	is a	dinoflagellate sulcus	`GO:0097618` The QuickGO GO:0097618 history records an is_a relation to GO:0097612.
dinoflagellate sulcal notch	extends to	dinoflagellate antapex	`GO:0097618` The GO:0097618 definition defines a sulcal notch as a dinoflagellate sulcus that extends to the posterior antapex. `GO:0097684` Gene Ontology term for the dinoflagellate antapex reached by the GO:0097618 sulcal notch.
dinoflagellate sulcal notch	gives bilobed appearance to	dinoflagellate hypocone	`GO:0097618` The GO:0097618 definition states that a sulcal notch makes the dinoflagellate hypocone appear bilobed. `GO:0097614` Gene Ontology term for the dinoflagellate hypocone whose bilobed appearance can indicate a sulcal notch.

Discussions

CURATION_TODO (OPEN): Add sulcal-notch molecular components only after directly localized constituents and exact source-neutral family groundings have been identified. GO defines the dinoflagellate sulcal notch morphologically as a sulcus extension to the antapex, but this pass did not find exact family-level evidence for sulcal-notch-specific molecular constituents.
INTERPRETATION (RESOLVED): Keep dinoflagellate sulcal notch separate from the general dinoflagellate sulcus unless curating the broader GO:0097612 class. QuickGO records GO:0097618 as an is_a child of GO:0097612 for a sulcus that extends to the posterior antapex and can make the hypocone appear bilobed, so the sulcal notch should remain a specialized child class of the general sulcus.
INTERPRETATION (RESOLVED): Model the dinoflagellate sulcal notch as a sulcus extension to the antapex that affects hypocone shape, not as an antapex or hypocone child class. GO:0097618 is_a GO:0097612 and its definition states that a sulcal notch extends to the antapex and can make the hypocone appear bilobed, so its antapex and hypocone links are morphological adjacency and appearance edges rather than subclass relations.

Evidence

GO:0097618 Gene Ontology cellular-component term for the dinoflagellate sulcal notch, a sulcus subclass that extends to the antapex and can make the hypocone appear bilobed.
GO:0097612 Gene Ontology cellular-component term for the dinoflagellate sulcus, the direct is_a parent in the GO:0097618 history.
GO:0097684 Gene Ontology cellular-component term for the dinoflagellate antapex reached by the GO:0097618 sulcal notch.
GO:0097614 Gene Ontology cellular-component term for the dinoflagellate hypocone that GO:0097618 says can appear bilobed when a sulcal notch is present.
PMID:7002229 PubMed record for Taylor 1980, the subscription Biosystems dinoflagellate-evolution review cited by GO:0097618; EuropePMC reported no PMC, open-access, full-text, or PDF route in this pass.
DOI:10.1016/0303-2647(80)90006-4 Crossref and EuropePMC metadata identify DOI:10.1016/0303-2647(80)90006-4 as the Taylor 1980 Biosystems review behind PMID:7002229; no article-body text was reachable through the checked metadata routes, so this record uses it only as bibliographic corroboration for the GO definition xref.

Curation history

2026-10-02T22:22:48Z codex · CREATED_RECORD — Scaffolded by scripts/new_record.py
2026-10-02T22:23:33Z codex · EXPANDED_RECORD — Added GO sulcal-notch synonyms, GO sulcus parentage, Dinophyceae taxon evidence, sulcal-notch/sulcus/antapex/hypocone topology, Taylor 1980 metadata-only evidence, and curation discussions for molecular components and the sulcal-notch/sulcus boundary.
2026-10-02T22:38:40Z codex · ADDRESSED_PR_REVIEW — Addressed PR #1948 review issues #1949 and #1950 by adding edge-level antapex and hypocone GO evidence and documenting that the sulcal notch reaches the antapex and changes hypocone shape without being an antapex or hypocone class.

Source: data/structures/other/dinoflagellate_sulcal_notch.yaml