contractile vacuolar membrane

GO:0031164 · Membrane organelle · Membrane · Proposed

The lipid bilayer surrounding the contractile vacuole. [GO:0031164]

Synonyms: contractile vacuole membrane

Part of: contractile vacuole (GO:0000331)

Xrefs: uniprot.location:SL-0074 — Contractile vacuole membrane

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
contractile-vacuole lipid bilayer	Lipid	part of	Reviewed label only (reviewed name; no accession asserted)			ESSENTIAL	Bounding bilayer that separates the contractile-vacuole lumen from the cytosol and carries water channels involved in vacuole filling. `GO:0031164` GO:0031164 identifies the contractile vacuolar membrane as the lipid bilayer surrounding the contractile vacuole. `uniprot.location:SL-0074` — Contractile vacuole membrane UniProt Subcellular Location SL-0074 maps Contractile vacuole membrane to GO:0031164.
contractile-vacuole membrane aquaporins	Protein	part of	Reviewed label only (reviewed name; no accession asserted)			UNKNOWN	Water channels that increase contractile-vacuole-system membrane permeability during water filling. `DOI:10.1042/BC20070091` Nishihara et al. 2008 cloned an Amoeba proteus aquaporin and localized it to the contractile vacuole membrane and perivacuolar vesicles. `DOI:10.1016/j.ejop.2024.126078` More et al. 2024 review channels implicated in contractile-vacuole filling.

Taxonomic distribution

NCBITaxon:2759 Eukaryota — RARE: Contractile vacuoles and their surrounding membranes occur patchily in unicellular freshwater and soil eukaryotes rather than across all eukaryotes. [DOI:10.1016/j.ejop.2024.126078]

Canonical examples

NCBITaxon:5775 Amoeba proteus — Amoeba model in which aquaporin and V-ATPase were localized to the contractile-vacuole membrane and associated vesicles. [DOI:10.1042/BC20070091]

Functions

contractile-vacuole membrane permeation — The contractile vacuolar membrane carries aquaporin water channels that increase membrane water permeability during contractile-vacuole filling.
- DOI:10.1042/BC20070091 Nishihara et al. 2008 localized aquaporin and V-ATPase to Amoeba contractile-vacuole-system membranes.

Mechanism graphs

Contractile-vacuole aquaporins and perivacuolar V-ATPase support filling (FUNCTION)

The contractile vacuolar membrane bounds the vacuole and carries aquaporins that support water permeability, while neighboring V-ATPase-positive vesicles support ion-gradient steps in vacuole filling.

Subject	Predicate	Object	Evidence
contractile vacuolar membrane	bounds	contractile vacuole	`GO:0031164` GO:0031164 defines the membrane as the lipid bilayer surrounding the contractile vacuole.
perivacuolar V-ATPase	resides in	perivacuolar V-ATPase-positive vesicles	`DOI:10.1042/BC20070091` Nishihara et al. 2008 detected V-ATPase-positive vesicles around the Amoeba contractile vacuole.
perivacuolar V-ATPase	contributes to	osmotic gradient toward the vacuole	`DOI:10.1042/BC20070091` Nishihara et al. 2008 interpreted V-ATPase-positive vesicles around the Amoeba contractile vacuole as participants in osmotic-gradient generation.
contractile-vacuole membrane aquaporins	increase	contractile-vacuole membrane water permeability	`DOI:10.1042/BC20070091` Nishihara et al. 2008 localized Amoeba ApAQP to the contractile vacuole membrane and perivacuolar vesicles.
contractile-vacuole membrane water permeability	supports	contractile-vacuole filling	`DOI:10.1042/BC20070091` Nishihara et al. 2008 proposed that Amoeba ApAQP helps explain high CV membrane water permeability.

Discussions

CURATION_TODO (OPEN): Resolve exact contractile-vacuolar membrane lipid and aquaporin groundings, and determine whether perivacuolar V-ATPase-positive vesicles warrant a separate record. The membrane record captures the lipid boundary and aquaporin-mediated water permeability at the exact CV membrane. V-ATPase-positive perivacuolar vesicles are represented only as graph context because the cited Amoeba localization does not make them constituents of GO:0031164.

Evidence

GO:0031164 Gene Ontology cellular-component term for the contractile vacuolar membrane.
GO:0005774 Gene Ontology cellular-component parent term for the vacuolar membrane.
GO:0000331 Gene Ontology cellular-component term for the containing contractile vacuole.
uniprot.location:SL-0074 — Contractile vacuole membrane UniProt Subcellular Location entry SL-0074 maps to GO:0031164 and lists contractile vacuolar membrane as an exact synonym.
DOI:10.1242/jcs.115.14.2893 Clarke et al. 2002, Dynamics of the vacuolar H+-ATPase in the contractile vacuole complex and the endosomal pathway of Dictyostelium cells, Journal of Cell Science.
DOI:10.1042/BC20070091 Nishihara et al. 2008, Presence of aquaporin and V-ATPase on the contractile vacuole of Amoeba proteus, Biology of the Cell.
DOI:10.1016/j.ejop.2024.126078 More et al. 2024, Contractile vacuoles: a rapidly expanding and occasionally diminishing understanding, European Journal of Protistology.

Curation history

2026-09-13T17:21:37Z codex · CREATED_RECORD — Scaffolded by scripts/new_record.py
2026-09-13T17:22:46Z codex · EXPANDED_RECORD — Added the UniProt SL contractile-vacuole membrane synonym and xref, vacuolar-membrane parentage, contractile-vacuole parthood, lipid bilayer, V-ATPase and aquaporin components, eukaryotic scope with amoebozoan examples, a membrane-permeation function, GO/UniProt/DOI evidence, a nonmechanistic filling graph, and a component-grounding TODO.
2026-09-13T17:27:36Z codex · REFINED_GRAPH — Retargeted the final water-permeability graph edge to a contractile-vacuole filling process node so the state supports the process rather than the organelle itself.
2026-09-13T17:33:26Z codex · ADDRESSED_PR_REVIEW — Addressed #817 by removing V-ATPase as a direct membrane component, retargeting the V-ATPase graph edge to perivacuolar vesicles, narrowing the canonical example to Amoeba proteus, and updating the component grounding TODO.

Source: data/structures/membrane_organelle/contractile_vacuolar_membrane.yaml