nuclear envelope

GO:0005635 · Membrane organelle · Membrane · Proposed

The double lipid bilayer that encloses the nucleus, separating its contents from the cytoplasm. It consists of an inner and outer nuclear membrane, with an intermembrane space (20-40 nm wide, also called the perinuclear space) between them. The envelope is supported by the nuclear lamina and contains nuclear pore complexes, which regulate molecular transport. [GO:0005635]

Part of: nucleus (GO:0005634)

Has part: nuclear inner membrane (GO:0005637); nuclear outer membrane (GO:0005640); nuclear envelope lumen (GO:0005641); nuclear pore (GO:0005643)

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

Components

Component	Type	Part of / acts on	Grounding	Essential	Role
nuclear inner membrane	Lipid	part of	`GO:0005637`	ESSENTIAL	Lumen-facing lipid bilayer of the nuclear envelope. `GO:0005637` GO:0005637 defines the nuclear inner membrane as the lumen-facing lipid bilayer of the nuclear envelope.
nuclear outer membrane	Lipid	part of	`GO:0005640`	ESSENTIAL	Cytoplasm-facing lipid bilayer of the nuclear envelope, continuous with the endoplasmic reticulum. `GO:0005640` GO:0005640 defines the nuclear outer membrane as the cytoplasm-facing lipid bilayer of the nuclear envelope.
nuclear pore	Protein complex	part of	`GO:0005643`	UNKNOWN	Protein complex embedded in the nuclear envelope where the inner and outer membranes join to gate exchange with the cytoplasm. `GO:0005643` GO:0005643 defines the nuclear pore as a protein complex that provides a discrete opening where the inner and outer nuclear membranes join.

Taxonomic distribution

NCBITaxon:2759 Eukaryota — COMMON: Nuclear envelopes separate the nucleus from the cytoplasm in eukaryotic cells. [DOI:10.1101/cshperspect.a000539]
NCBITaxon:4932 Saccharomyces cerevisiae — COMMON: Budding-yeast nuclear envelopes can form nucleus-vacuole junctions through the outer nuclear membrane protein Nvj1p. [DOI:10.1091/mbc.11.7.2445]

Canonical examples

NCBITaxon:4932 Saccharomyces cerevisiae — Budding-yeast model in which outer-nuclear-membrane Nvj1p and vacuolar Vac8p were shown to form nucleus-vacuole junctions. [DOI:10.1091/mbc.11.7.2445]

Functions

nucleocytoplasmic transport GO:0006913 — Nuclear pores in the envelope gate directed molecular movement between the nucleus and cytoplasm.
- GO:0005643 GO:0005643 places nuclear pores at the joined inner and outer membranes of the nuclear envelope.
- GO:0006913 GO:0006913 defines nucleocytoplasmic transport as directed movement between the nucleus and cytoplasm.
- DOI:10.1534/genetics.111.127803 Aitchison and Rout 2012 review budding-yeast NPC organization and transport.
nuclear envelope organization GO:0006998 — Cells assemble, arrange, remodel, and disassemble nuclear envelope membranes and embedded pores during nuclear envelope organization.
- GO:0006998 GO:0006998 defines nuclear envelope organization as assembly, arrangement, or disassembly of the nuclear envelope.
- DOI:10.1101/cshperspect.a000539 Hetzer 2010 reviews nuclear envelope remodeling during the cell cycle.

Mechanism graphs

Nuclear envelope membranes gate the nucleus (FUNCTION)

In budding yeast, inner and outer nuclear membranes form the nuclear envelope, and nuclear pores cross the envelope to mediate exchange between the nucleus and cytoplasm.

Subject	Predicate	Object	Evidence
nuclear inner membrane	is part of	nuclear envelope	`GO:0005637` GO:0005637 defines the nuclear inner membrane as part of the nuclear envelope.
nuclear outer membrane	is part of	nuclear envelope	`GO:0005640` GO:0005640 defines the nuclear outer membrane as part of the nuclear envelope.
nuclear envelope	contains	nuclear envelope lumen	`GO:0005641` GO:0005641 defines the nuclear envelope lumen as the region between the two lipid bilayers of the nuclear envelope.
nuclear pore	spans	nuclear envelope	`GO:0005643` GO:0005643 places the nuclear pore at the junction between the inner and outer nuclear membranes.
nuclear pore	mediates	nucleocytoplasmic transport	`GO:0006913` GO:0006913 defines nucleocytoplasmic transport as directed movement between the nucleus and cytoplasm. `DOI:10.1534/genetics.111.127803` Aitchison and Rout 2012 review transport through the budding-yeast nuclear pore complex.

Discussions

CURATION_TODO (OPEN): Resolve exact source-neutral boundaries and groundings for inner- and outer-nuclear-membrane protein cohorts. This first nuclear envelope record grounds the envelope membranes and nuclear pore exactly, but avoids grouping diverse nuclear-envelope-resident proteins into one ungrounded component class.

Evidence

GO:0005635 Gene Ontology cellular-component term for nuclear envelope.
GO:0031967 Gene Ontology cellular-component term for organelle envelope.
GO:0005634 Gene Ontology cellular-component term for nucleus.
GO:0005637 Gene Ontology cellular-component term for nuclear inner membrane.
GO:0005640 Gene Ontology cellular-component term for nuclear outer membrane.
GO:0005641 Gene Ontology cellular-component term for nuclear envelope lumen.
GO:0005643 Gene Ontology cellular-component term for nuclear pore.
GO:0006913 Gene Ontology biological-process term for nucleocytoplasmic transport.
GO:0006998 Gene Ontology biological-process term for nuclear envelope organization.
DOI:10.1101/cshperspect.a000539 Hetzer 2010, 'The Nuclear Envelope', Cold Spring Harbor Perspectives in Biology.
DOI:10.1091/mbc.11.7.2445 Pan et al. 2000, 'Nucleus-Vacuole Junctions in Saccharomyces cerevisiae Are Formed Through the Direct Interaction of Vac8p with Nvj1p', Molecular Biology of the Cell.
DOI:10.1534/genetics.111.127803 Aitchison and Rout 2012, 'The Yeast Nuclear Pore Complex and Transport Through It', Genetics.

Curation history

2026-09-12T05:28:15Z codex · CREATED_RECORD — Scaffolded by scripts/new_record.py
2026-09-12T05:29:32Z codex · EXPANDED_RECORD — Added organelle-envelope parentage, nucleus parthood, exact inner and outer nuclear membrane plus nuclear-pore parts, Eukaryota and Saccharomyces scope, nuclear-envelope functions, DOI/GO evidence, a nonmechanistic pore-gated-envelope graph, and a nuclear-membrane protein grounding TODO.
2026-09-12T05:35:56Z codex · REVIEW_FIXES — Resolved review issues #591 and #592 by adding the GO:0005641 nuclear envelope lumen as a core part and adding direct Aitchison/Rout NPC evidence to the nucleocytoplasmic transport function and graph edge.

Source: data/structures/membrane_organelle/nuclear_envelope.yaml