septin complex

GO:0031105 · Cytoskeleton · Multiprotein complex · Proposed

A protein complex containing septins. Typically, these complexes contain multiple septins and are oligomeric. [GO:0031105]

Part of: GO:0032156 — septin cytoskeleton (no local record); cell cortex (GO:0005938)

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 associate into oligomeric septin protein complexes. `GO:0031105` GO:0031105 defines a septin complex as a protein complex containing septins that is typically oligomeric. `DOI:10.1091/mbc.E04-07-0640` An et al. 2004 assayed fission-yeast septin requirements for septin complex formation.

NCBITaxon:4896 Schizosaccharomyces pombe — COMMON: Fission yeast Spn1, Spn2, Spn3 and Spn4 form an oligomeric septin complex. An et al. 2004 detected at least two copies of each septin and proposed a two-copy-per-subunit model, while noting that the exact stoichiometry remained to be proven rigorously. [DOI:10.1091/mbc.E04-07-0640]

NCBITaxon:4896 Schizosaccharomyces pombe — Fission-yeast model in which An et al. 2004 mapped an oligomeric septin complex containing Spn1, Spn2, Spn3 and Spn4. [DOI:10.1091/mbc.E04-07-0640]

Septin proteins associate into oligomeric septin protein complexes.

Subject	Predicate	Object	Evidence
septin proteins	oligomerize into	septin complex	`GO:0031105` GO:0031105 defines the septin complex as an oligomeric protein complex containing septins. `DOI:10.1091/mbc.E04-07-0640` An et al. 2004 tested which fission-yeast septins are required for septin complex formation.

INTERPRETATION (RESOLVED): Keep oligomeric septin complexes distinct from higher-order septin filaments, rings, and collars. GO:0031105 denotes oligomeric septin protein complexes. GO:0005940 denotes higher-order cortical septin rings at division planes, and GO:0032173 denotes tubular septin collars assembled from ordered filament arrays.
CURATION_TODO (OPEN): Resolve exact source-neutral family groundings for septin-complex septin proteins. The first septin-complex record uses a reviewed-label-only septin protein cohort rather than guessing a family CURIE that may not exactly delimit every septin protein participating in GO:0031105 oligomeric complexes.

GO:0031105 Gene Ontology cellular-component term for the septin complex.
GO:0032991 Gene Ontology cellular-component parent term for protein-containing complexes.
GO:0032156 — septin cytoskeleton Gene Ontology cellular-component term for the septin cytoskeleton.
GO:0005938 Gene Ontology cellular-component term for the cell cortex.
DOI:10.1091/mbc.E04-07-0640 An, Morrell, Jennings, Link and Gould 2004, 'Requirements of fission yeast septins for complex formation, localization, and function', Molecular Biology of the Cell.

2026-09-30T10:02:21Z codex · CREATED_RECORD — Scaffolded by scripts/new_record.py
2026-09-30T10:04:17Z codex · EXPANDED_RECORD — Added protein-containing-complex parentage, septin-cytoskeleton and cell-cortex parthood, a reviewed-label-only septin constituent, Schizosaccharomyces pombe scope and canonical example evidence, a GO-backed oligomerization graph, and complex-boundary and component-grounding discussions.
2026-09-30T10:23:25Z codex · ADDRESSED_REVIEW — Resolved #1820 from PR #1819 by tightening the Schizosaccharomyces pombe taxonomic-distribution and canonical-example notes to cite the Spn1/Spn2/Spn3/Spn4 oligomeric septin complex.
2026-10-11T13:43:15Z codex · ADDRESS_SAVED_REVIEW — Addressed #2215: Qualified the detected minimum of two Spn1-4 copies versus the proposed exact two-copy model in An et al. 2004.