actin cortical patch

GO:0030479 · Cytoskeleton · Filament · Proposed

An endocytic patch formed from branched actin filaments just beneath the plasma membrane that assembles, moves, and disassembles rapidly. [GO:0030479]

Synonyms: actin patch

Part of: cell cortex (GO:0005938); GO:0030864 — cortical actin cytoskeleton (no local record)

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
actin	Protein	part of	Reviewed label only (reviewed name; no accession asserted)	ACT1		UNKNOWN	Polymerizes into the short, branched filaments that form the yeast actin cortical patch network. `DOI:10.1083/jcb.200404159` Young, Cooper and Bridgman 2004 examined Saccharomyces cerevisiae actin patches by correlative fluorescence and electron microscopy.
Arp2/3 protein complex	Protein complex	part of	`GO:0005885`			UNKNOWN	Branch-forming actin-nucleation complex that builds the dendritic actin filament network in cortical patches. `DOI:10.1083/jcb.200404159` Young, Cooper and Bridgman 2004 described yeast actin-patch branches characteristic of the Arp2/3 complex.

Taxonomic distribution

NCBITaxon:4932 Saccharomyces cerevisiae — COMMON: Budding yeast forms dynamic actin cortical patches at the cell cortex during endocytic internalization. [DOI:10.1016/S0092-8674(03)00883-3]

Canonical examples

NCBITaxon:4932 Saccharomyces cerevisiae — Budding-yeast model in which cortical actin patches were imaged as short, branched Arp2/3-like actin-filament networks. [DOI:10.1083/jcb.200404159]

Functions

actin cortical patch assembly GO:0000147 — The actin cortical patch is produced by assembly of a branched actin network at cortical endocytic sites.
- GO:0000147 GO:0000147 denotes assembly of an actin cortical patch.
- DOI:10.1371/journal.pbio.0060001 Galletta, Chuang and Cooper 2008 tracked actin patch assembly and movement in Arp2/3-regulator mutants.
endocytic internalization — Yeast actin cortical patches assemble at cortical endocytic sites and move inward as internalization proceeds.
- DOI:10.1016/S0092-8674(03)00883-3 Kaksonen, Sun and Drubin 2003 followed receptors, adaptors and actin during yeast endocytic internalization.

Mechanism graphs

Arp2/3 nucleates a branched actin network in yeast cortical patches (ASSEMBLY)

In Saccharomyces cerevisiae, Arp2/3 promotes formation of short branched actin filaments at cortical endocytic sites, producing actin cortical patches.

Subject	Predicate	Object	Evidence
Arp2/3 protein complex	nucleates branches in	actin cortical patch	`DOI:10.1083/jcb.200404159` Young, Cooper and Bridgman 2004 linked the patch branch pattern to Arp2/3-mediated actin polymerization.
actin	polymerizes into	actin cortical patch	`DOI:10.1083/jcb.200404159` Young, Cooper and Bridgman 2004 found networks of branched actin filaments in yeast actin patches.
actin cortical patch	assembles at	cortical endocytic site	`DOI:10.1016/S0092-8674(03)00883-3` Kaksonen, Sun and Drubin 2003 analyzed actin recruitment during yeast endocytic internalization.

Discussions

CURATION_TODO (OPEN): Resolve exact source-neutral groundings and record scope for cortical actin-patch nucleation-promoting factors, capping proteins, fimbrin, cofilin, and adaptor-linked patch proteins. This first actin cortical patch record captures the branched actin network and Arp2/3 branch nucleator but leaves the broader, timed endocytic actin module to a later pass to avoid mixing transient assembly factors with stable patch constituents.

Evidence

GO:0030479 Gene Ontology cellular-component term for the actin cortical patch.
GO:0015629 — actin cytoskeleton Actin cytoskeleton is a containing structure, not an is-a parent of the patch; the direct GO parthood relation uses cortical actin cytoskeleton.
GO:0005885 Gene Ontology cellular-component term for the Arp2/3 protein complex.
GO:0000147 Gene Ontology biological-process term for actin cortical patch assembly.
DOI:10.1016/S0092-8674(03)00883-3 Kaksonen, Sun and Drubin 2003, A Pathway for Association of Receptors, Adaptors, and Actin during Endocytic Internalization, Cell.
DOI:10.1083/jcb.200404159 Young, Cooper and Bridgman 2004, Yeast actin patches are networks of branched actin filaments, Journal of Cell Biology.
DOI:10.1371/journal.pbio.0060001 Galletta, Chuang and Cooper 2008, Distinct Roles for Arp2/3 Regulators in Actin Assembly and Endocytosis, PLoS Biology.
GO:0061645 — endocytic patch Endocytic patch is the native GO is-a parent of GO:0030479 actin cortical patch.
GO:0030864 — cortical actin cytoskeleton Cortical actin cytoskeleton contains the actin cortical patch through the native GO part_of relation.

Curation history

2026-09-12T08:27:06Z codex · CREATED_RECORD — Scaffolded by scripts/new_record.py
2026-09-12T08:27:53Z codex · EXPANDED_RECORD — Added actin-cytoskeleton parentage, cell-cortex parthood, an exact actin-patch synonym, reviewed-label-only actin and GO-grounded Arp2/3 components, Saccharomyces scope, actin cortical patch assembly and endocytic internalization functions, DOI/GO evidence, a nonmechanistic branched actin-patch assembly graph, and an accessory component-grounding TODO.
2026-09-12T08:34:59Z codex · ADDRESSED_PR_REVIEW — Resolved PR #615 review issues #616 and #617 by removing the downstream endocytic-internalization node from the assembly graph and moving Arp2/3-regulator evidence off the Arp2/3 component.
2026-10-11T07:14:17Z codex · ADDRESS_SAVED_REVIEW — Addressed #2188: Corrected endocytic-patch is-a parent and cortical actin-cytoskeleton parthood while retaining cell-cortex parthood and prior graph/evidence placement fixes.

Source: data/structures/cytoskeleton/actin_cortical_patch.yaml