hyphal septin cap

GO:0032164 · Cytoskeleton · Filament · Proposed

A faint structure formed of septins found at the leading edge of growth in hyphae of fungal cells growing filamentously. This cap of septins colocalizes with a region of the plasma membrane that is rich in ergosterol. [GO:0032164]

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 the faint cap at the leading edge of filamentous fungal hyphae. `GO:0032164` GO:0032164 defines the hyphal septin cap as a structure formed of septins. `GO:0032159` GO:0032159 defines the broader septin cap as a structure formed of septins.

Mechanism graphs

Hyphal septin-cap apical topology (ASSEMBLY)

Septin proteins form a faint cap at the leading edge of filamentous fungal hyphae.

Subject	Predicate	Object	Evidence
septin proteins	assemble into	hyphal septin cap	`GO:0032164` GO:0032164 defines the hyphal septin cap as a structure formed of septins.
hyphal septin cap	forms at	hyphal growth tip	`GO:0032164` GO:0032164 localizes the hyphal septin cap to the leading edge of growth in hyphae.
hyphal septin cap	colocalizes with	ergosterol-rich plasma membrane region	`GO:0032164` GO:0032164 defines hyphal septin caps by colocalization with an ergosterol-rich plasma-membrane region.

Discussions

INTERPRETATION (RESOLVED): Keep the hyphal septin cap distinct from the generic septin cap, the germ-tube cap, and septation-site septin rings. GO:0032164 denotes the apical septin cap at the leading edge of filamentous fungal hyphae. GO:0032159 denotes the broader hyphal-or-germ-tube septin-cap class, GO:0032171 denotes the germ-tube cap sibling, and GO:0032168 denotes a ring-shaped septin structure at future hyphal septation sites.
CURATION_TODO (OPEN): Resolve exact source-neutral family groundings for hyphal-cap septin proteins. The first hyphal septin-cap record uses a reviewed-label-only septin protein cohort rather than guessing InterPro, Pfam, or NCBIfam accessions that may not exactly delimit all septins in this apical hyphal cap.

Evidence

GO:0032164 Gene Ontology cellular-component term for the hyphal septin cap.
GO:0032159 Gene Ontology cellular-component parent term for the septin cap.
DOI:10.1128/EC.4.9.1503-1512.2005 Douglas et al. 2005, 'Septin function in yeast model systems and pathogenic fungi', Eukaryotic Cell.

Curation history

2026-09-30T11:54:27Z codex · CREATED_RECORD — Scaffolded by scripts/new_record.py
2026-09-30T11:55:20Z codex · EXPANDED_RECORD — Added GO-backed septin-cap parentage, a reviewed-label-only septin constituent, GO-backed hyphal apical-cap topology, and hyphal-cap boundary and component-grounding discussions.

Source: data/structures/cytoskeleton/hyphal_septin_cap.yaml