mitochondrial inner boundary membrane

GO:0097002 · Membrane organelle · Membrane · Proposed

The portion of the mitochondrial inner membrane that is not invaginated to form cristae and lies parallel to the outer membrane. [GO:0097002]

Part of: mitochondrial inner membrane (GO:0005743)

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
mitochondrial inner boundary lipid bilayer	Lipid	part of	Reviewed label only (reviewed name; no accession asserted)			ESSENTIAL	Non-invaginated lipid bilayer domain of the mitochondrial inner membrane that runs parallel to the outer membrane. `GO:0097002` GO:0097002 identifies the inner boundary membrane as the portion of the mitochondrial inner membrane that is not invaginated to form cristae.

Taxonomic distribution

NCBITaxon:2759 Eukaryota — VARIABLE: Canonical inner boundary membranes occur with crista-forming mitochondria, while some anaerobic eukaryotic lineages carry reduced mitochondrion-related organelles. [GO:0097002]
NCBITaxon:4932 Saccharomyces cerevisiae — COMMON: Budding-yeast mitochondrial inner membranes contain inner boundary and crista membrane domains connected by crista junctions. [DOI:10.1016/j.devcel.2011.08.026]

Canonical examples

NCBITaxon:4932 Saccharomyces cerevisiae — Reference yeast for MINOS and MICOS studies that connect crista membranes to the mitochondrial inner boundary membrane through crista junctions. [DOI:10.1016/j.devcel.2011.08.026]

Functions

inner mitochondrial membrane organization GO:0007007 — The inner boundary membrane provides the non-invaginated inner-membrane domain to which cristae remain connected through crista junctions.
- GO:0097002 GO:0097002 defines the inner boundary membrane as the non-invaginated portion of the mitochondrial inner membrane.
- GO:0044284 GO:0044284 defines the crista junction as the tubular connection between a mitochondrial crista and the inner boundary membrane.
- GO:0007007 GO:0007007 defines inner mitochondrial membrane organization as assembly, arrangement of constituent parts, or disassembly of the mitochondrial inner membrane.

Mechanism graphs

Yeast mitochondrial inner boundary membrane topology (ASSEMBLY)

In budding yeast, the inner boundary membrane is the non-invaginated mitochondrial inner-membrane domain that connects to crista membranes through crista junctions.

Subject	Predicate	Object	Evidence
mitochondrial inner boundary membrane	is part of	mitochondrial inner membrane	`GO:0097002` GO:0097002 defines the inner boundary membrane as a portion of the mitochondrial inner membrane. `GO:0005743` GO:0005743 identifies the mitochondrial inner membrane.
mitochondrial inner boundary membrane	is connected to	mitochondrial crista junction	`GO:0044284` GO:0044284 defines a crista junction as the tubular structure that connects a mitochondrial crista to the inner boundary membrane.
mitochondrial crista junction	connects	mitochondrial crista	`GO:0044284` GO:0044284 defines a crista junction as the connection between a crista and the inner boundary membrane. `GO:0030061` GO:0030061 defines a mitochondrial crista as an inward fold of the mitochondrial inner membrane.
mitochondrial inner boundary membrane	participates in	inner mitochondrial membrane organization	`GO:0097002` GO:0097002 distinguishes the non-invaginated inner boundary membrane from invaginated cristae. `GO:0007007` GO:0007007 denotes assembly, arrangement of constituent parts, or disassembly of the mitochondrial inner membrane.

Discussions

CURATION_TODO (OPEN): Resolve an exact source-neutral grounding for the lipid constituent of the mitochondrial inner boundary membrane. GO:0097002 identifies the whole inner boundary membrane, but the lipid-bilayer constituent is intentionally left as reviewed-label-only until an exact source-neutral lipid or membrane-constituent CURIE is curated.

Evidence

GO:0097002 Gene Ontology cellular-component term for mitochondrial inner boundary membrane.
GO:0005743 Gene Ontology cellular-component term for mitochondrial inner membrane.
GO:0030061 Gene Ontology cellular-component term for mitochondrial crista.
GO:0044284 Gene Ontology cellular-component term for mitochondrial crista junction.
GO:0007007 Gene Ontology biological-process term for inner mitochondrial membrane organization.
DOI:10.1016/j.devcel.2011.08.026 von der Malsburg et al. 2011, 'Dual role of mitofilin in mitochondrial membrane organization and protein biogenesis', Developmental Cell.
DOI:10.7554/elife.07739 Friedman et al. 2015, 'MICOS coordinates with respiratory complexes and lipids to establish mitochondrial inner membrane architecture', eLife.
DOI:10.1038/nature12985 Friedman and Nunnari 2014, 'Mitochondrial form and function', Nature.

Curation history

2026-09-30T04:29:35Z codex · CREATED_RECORD — Scaffolded by scripts/new_record.py
2026-09-30T04:31:39Z codex · EXPANDED_RECORD — Added mitochondrial-inner-membrane parthood, a reviewed-label-only lipid-bilayer component, Eukaryota and Saccharomyces scope, inner-membrane-organization function evidence, a nonmechanistic inner-boundary topology graph, and a lipid-bilayer grounding TODO.

Source: data/structures/membrane_organelle/mitochondrial_inner_boundary_membrane.yaml