endoplasmic reticulum Sec complex

GO:0031205 · Other · Multiprotein complex · Proposed

An endoplasmic reticulum membrane-associated complex involved in the translocation of proteins that are targeted to the ER. In yeast, this complex consists of two subcomplexes, namely, the Sec61 complex and the Sec62/Sec63 complex. [GO:0031205]

Part of: endoplasmic reticulum membrane (GO:0005789)

Has part: Sec61 translocon complex (GO:0005784); Sec62/Sec63 complex (GO:0031207)

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

Taxonomic distribution

NCBITaxon:4932 Saccharomyces cerevisiae — COMMON: Budding yeast contains an ER-membrane Sec complex assembled from the Sec61 heterotrimer and the Sec62/Sec63 subcomplex for posttranslational protein import. [DOI:10.1016/0092-8674(95)90077-2]

Canonical examples

NCBITaxon:4932 Saccharomyces cerevisiae — Yeast model in which purified Sec proteins and Kar2p reconstituted posttranslational ER protein transport. [DOI:10.1016/0092-8674(95)90077-2]

Functions

posttranslational ER protein import — The ER Sec complex brings the Sec61 protein-conducting channel and the Sec62/Sec63 subcomplex together at the ER membrane to support Kar2/BiP-coupled posttranslational import of substrate proteins into the endoplasmic reticulum.
- GO:0031205 GO:0031205 defines the ER Sec complex as an ER-membrane complex involved in protein translocation into the ER.
- DOI:10.1016/0092-8674(95)90077-2 Panzner et al. 1995 reconstituted yeast posttranslational protein transport with a purified Sec-protein complex and Kar2p.
- DOI:10.1091/mbc.e03-06-0390 Plath et al. 2004 photo-crosslinked a substrate precursor to Sec62p and Sec61p in the yeast Sec complex during posttranslational ER import.
- DOI:10.1038/s41586-018-0856-x Wu, Cabanos and Rapoport 2019 determined the structure of the yeast ER post-translational protein translocation machinery.

Mechanism graphs

ER Sec complex links Sec61 with Sec62/Sec63 (FUNCTION)

The yeast ER Sec complex contains the Sec61 translocon and Sec62/Sec63 subcomplexes at the endoplasmic-reticulum membrane and supports posttranslational ER protein import.

Subject	Predicate	Object	Evidence
Sec61 translocon complex	is subcomplex of	endoplasmic reticulum Sec complex	`GO:0031205` GO:0031205 defines the yeast ER Sec complex as containing the Sec61 and Sec62/Sec63 subcomplexes.
Sec62/Sec63 complex	is subcomplex of	endoplasmic reticulum Sec complex	`GO:0031205` GO:0031205 defines the yeast ER Sec complex as containing the Sec61 and Sec62/Sec63 subcomplexes. `DOI:10.1038/s41586-018-0856-x` Wu, Cabanos and Rapoport 2019 structurally resolved the Sec62/Sec63 subcomplex with Sec61 in the yeast post-translational ER translocation machinery.
endoplasmic reticulum Sec complex	is embedded in	endoplasmic reticulum membrane	`GO:0031205` GO:0031205 defines the complex as endoplasmic-reticulum membrane associated. `GO:0005789` GO:0005789 identifies the endoplasmic reticulum membrane.
endoplasmic reticulum Sec complex	supports	posttranslational ER protein import	`DOI:10.1016/0092-8674(95)90077-2` Panzner et al. 1995 reconstituted posttranslational transport using purified Sec proteins and Kar2p. `DOI:10.1091/mbc.e03-06-0390` Plath et al. 2004 detected interactions between prepro-alpha-factor and Sec complex components during posttranslational transport.

Discussions

INTERPRETATION (RESOLVED): Should individual Sec61p, Sbh1p, Sss1p, Sec62p, Sec63p, Sec71p, or Sec72p subunits be duplicated as direct ER Sec complex components? GO:0031205 is the parent ER Sec complex made from Sec61 and Sec62/Sec63 subcomplexes in yeast. The individual Sec61p/Sbh1p/Sss1p and Sec62p/Sec63p/Sec71p/Sec72p proteins belong on those lower-level subcomplex records, so this parent record uses has_part links to avoid duplicating the same components at two hierarchy levels.

Evidence

GO:0031205 Gene Ontology cellular-component term for the endoplasmic reticulum Sec complex.
GO:0140534 Gene Ontology parent term for endoplasmic-reticulum protein-containing complexes.
GO:0005789 Gene Ontology cellular-component term for the endoplasmic reticulum membrane.
GO:0005784 Gene Ontology cellular-component term for the Sec61 translocon subcomplex of the yeast ER Sec complex.
GO:0031207 Gene Ontology cellular-component term for the Sec62/Sec63 subcomplex of the yeast ER Sec complex.
DOI:10.1016/0092-8674(95)90077-2 Panzner et al. 1995, Posttranslational protein transport in yeast reconstituted with a purified complex of Sec proteins and Kar2p, Cell.
DOI:10.1091/mbc.e03-06-0390 Plath et al. 2004, Interactions between Sec complex and prepro-alpha-factor during posttranslational protein transport into the endoplasmic reticulum, Molecular Biology of the Cell.
DOI:10.1038/s41586-018-0856-x Wu, Cabanos and Rapoport 2019, Structure of the post-translational protein translocation machinery of the ER membrane, Nature.

Curation history

2026-09-23T23:03:15Z codex · CREATED_RECORD — Scaffolded by scripts/new_record.py
2026-09-23T23:04:07Z codex · EXPANDED_RECORD — Added ER-protein-complex parentage, ER-membrane parthood, Sec61 and Sec62/Sec63 has-part subcomplexes, Saccharomyces scope, GO/DOI evidence, a nonmechanistic ER Sec topology graph, and a resolved subcomplex-boundary discussion.

Source: data/structures/other/endoplasmic_reticulum_sec_complex.yaml