septin collar

GO:0032173 · Cytoskeleton · Filament · Proposed

A tubular, hourglass-shaped structure composed of highly ordered arrays of septin filaments; in budding yeast cells, the septin collar forms from the initial septin ring by expanding into the daughter cell. [GO:0032173]

Synonyms: septin hourglass

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

Components

Component	Type	Part of / acts on	Grounding	Genes	Stoichiometry	Essential	Role
septin proteins	Protein	part of	Reviewed label only (reviewed name; no accession asserted)			ESSENTIAL	Septin GTPases that form highly ordered filament arrays in the tubular hourglass-shaped collar. `GO:0032173` GO:0032173 defines the septin collar as a tubular, hourglass-shaped structure composed of highly ordered arrays of septin filaments.

Taxonomic distribution

NCBITaxon:4932 Saccharomyces cerevisiae — COMMON: Saccharomyces cerevisiae cells reorganize the initial septin ring into an hourglass-shaped septin collar at the mother-bud neck after budding. [DOI:10.1091/mbc.E04-09-0764]

Canonical examples

NCBITaxon:4932 Saccharomyces cerevisiae — Budding-yeast model in which Bni4 and Kcc4 reporters were used to follow asymmetric protein localization relative to the septin ring and mother-bud-neck septin collar. [DOI:10.1091/mbc.E04-09-0764]

Mechanism graphs

Budding-yeast septin-ring to septin-collar topology (ASSEMBLY)

Septin proteins form highly ordered arrays in an hourglass-shaped collar after the initial budding-yeast septin ring expands into the daughter cell.

Subject	Predicate	Object	Evidence
septin proteins	assemble into	septin collar	`GO:0032173` GO:0032173 defines the septin collar as a tubular, hourglass-shaped array of septin filaments.
septin ring	expands into	septin collar	`GO:0032173` GO:0032173 describes the budding-yeast septin collar as forming from the initial septin ring by expansion into the daughter cell.

Discussions

INTERPRETATION (RESOLVED): Keep the generic septin collar distinct from localized bud-neck and hyphal septin-collar subtypes. GO:0032173 denotes the broader hourglass-shaped septin filament collar class, while GO:0032174 narrows the same architecture to the cellular bud neck and GO:0062140 narrows it to the pathogenic-fungal hyphae collar at plant plasmodesmata.
CURATION_TODO (OPEN): Resolve exact source-neutral family groundings for septin-collar septin proteins. The first generic septin-collar record reuses a reviewed-label-only septin protein cohort rather than guessing InterPro, Pfam, or NCBIfam accessions that may not exactly delimit all fungal septins that form collar architectures.

Evidence

GO:0032173 Gene Ontology cellular-component term for the septin collar.
GO:0032156 — septin cytoskeleton Gene Ontology cellular-component parent term for the septin cytoskeleton.
GO:0032174 Gene Ontology cellular-component child term for the cellular bud neck septin collar.
GO:0062140 Gene Ontology cellular-component child term for the hyphae septin collar.
DOI:10.1091/mbc.E04-09-0764 Kozubowski, Larson and Tatchell 2005, 'Role of the Septin Ring in the Asymmetric Localization of Proteins at the Mother-Bud Neck in Saccharomyces cerevisiae', Molecular Biology of the Cell.

Curation history

2026-09-30T07:49:49Z codex · CREATED_RECORD — Scaffolded by scripts/new_record.py
2026-09-30T07:52:19Z codex · EXPANDED_RECORD — Added septin-hourglass synonymy, septin-cytoskeleton parentage, a reviewed-label-only septin constituent, Saccharomyces distribution and canonical example evidence, GO-backed ring-to-collar topology, and collar-boundary and component-grounding discussions.
2026-09-30T08:17:49Z codex · ADDRESSED_REVIEW — Resolved #1815 by citing Kozubowski et al. 2005 for the Saccharomyces septin-collar distribution and canonical example rows.

Source: data/structures/cytoskeleton/septin_collar.yaml