ERMES complex

GO:0032865 · Other · Multiprotein complex · Proposed

A protein complex that links the endoplasmic reticulum with mitochondria and may have a role in promoting exchange of calcium and phospholipids between the two organelles. [GO:0032865]

Synonyms: ER-mitochondria encounter structure; Mdm10/Mdm12/Mmm1 complex; mitochore; MMM1 complex

Part of: mitochondrial outer membrane (GO:0005741)

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

Taxonomic distribution

NCBITaxon:4932 Saccharomyces cerevisiae — COMMON: Budding yeast contains ERMES at ER-mitochondria junctions; Kornmann et al. identified the Mmm1/Mdm10/Mdm12/Mdm34 complex as an ER-mitochondria tether. [DOI:10.1126/science.1175088]

Canonical examples

NCBITaxon:4932 Saccharomyces cerevisiae — Budding-yeast model in which a synthetic tether screen identified Mmm1, Mdm10, Mdm12, and Mdm34 as an ER-mitochondria tethering complex. [DOI:10.1126/science.1175088]

Mechanism graphs

ERMES links the ER with mitochondria (FUNCTION)

ERMES localizes at ER-mitochondria junctions, links the endoplasmic reticulum with the mitochondrial outer membrane, and contains an Mmm1-Mdm12 module that can transfer lipids between membranes in vitro.

Subject	Predicate	Object	Evidence
ERMES complex	is part of	mitochondrial outer membrane	`GO:0098799` GO places ERMES under the class of protein complexes that are part of the mitochondrial outer membrane.
ERMES complex	links	endoplasmic reticulum	`GO:0032865` GO:0032865 defines ERMES as a protein complex that links the ER with mitochondria. `DOI:10.1126/science.1175088` Kornmann et al. 2009 identified the Mmm1/Mdm10/Mdm12/Mdm34 complex as a molecular tether between ER and mitochondria.
ERMES complex	contains lipid-transfer module	Mmm1-Mdm12 intermembrane lipid transfer	`GO:0032865` GO:0032865 notes only a possible role for ERMES in calcium and phospholipid exchange between the linked organelles. `DOI:10.1083/jcb.201704119` Kawano et al. 2018 found that the Mmm1-Mdm12 complex mediated efficient lipid transfer between liposomes.

Discussions

CURATION_TODO (OPEN): Resolve exact source-neutral component groundings for Mmm1, Mdm10, Mdm12, and Mdm34 before adding ERMES subunit rows. GO exactly grounds the ERMES complex itself, but this first record does not assert InterPro, Pfam, NCBIfam, or UniProt family CURIEs for Mmm1, Mdm10, Mdm12, or Mdm34 until source-neutral family boundaries are verified.

Evidence

GO:0032865 Gene Ontology cellular-component term for the ERMES complex.
GO:0098799 Gene Ontology cellular-component parent term for outer mitochondrial membrane protein complexes.
GO:0005783 Gene Ontology cellular-component term for the endoplasmic reticulum.
GO:0005741 Gene Ontology cellular-component term for the mitochondrial outer membrane.
DOI:10.1126/science.1175088 Kornmann et al. 2009, An ER-mitochondria tethering complex revealed by a synthetic biology screen, Science.
DOI:10.1083/jcb.201704119 Kawano et al. 2018, Structure-function insights into direct lipid transfer between membranes by Mmm1-Mdm12 of ERMES, Journal of Cell Biology.

Curation history

2026-09-18T15:54:21Z codex · CREATED_RECORD — Scaffolded by scripts/new_record.py
2026-09-18T15:55:15Z codex · EXPANDED_RECORD — Added GO synonymy, outer-mitochondrial-membrane protein-complex parentage, mitochondrial-outer-membrane parthood, Saccharomyces scope, ER-mitochondria tethering and lipid-exchange evidence, a nonmechanistic ERMES graph, and an ERMES subunit-boundary TODO.
2026-09-18T16:06:01Z codex · ADDRESS_REVIEW — Resolved #1164 and #1165 by removing the over-assertive top-level lipid-exchange function, dropping the broad mitochondrion graph node and duplicate tethering edge, and narrowing the lipid-transfer graph claim to the Mmm1-Mdm12 in vitro module.

Source: data/structures/other/ermes_complex.yaml