chaperonin-containing T-complex

GO:0005832 · Other · Multiprotein complex · Proposed

A multisubunit ring-shaped complex that mediates protein folding in the cytosol without a cofactor. [GO:0005832]

Synonyms: TRiC; TCP-1 ring complex; CCT complex

Part of: GO:0005829 — cytosol (no local record)

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
CCT alpha subunit	Protein	part of	Reviewed label only (reviewed name; no accession asserted)	CCT1	two copies per double-ring complex	UNKNOWN	One of the eight paralogous subunits that forms each hetero-octameric chaperonin-containing T-complex ring. `DOI:10.1038/emboj.2011.208` Dekker et al. 2011 solved the Saccharomyces cerevisiae CCT crystal structure and assigned Cct1p through Cct8p within its hetero-oligomeric rings. `PMID:8771707` Stoldt et al. 1996 reviewed CCT subunits in Saccharomyces cerevisiae and related yeasts.
CCT beta subunit	Protein	part of	Reviewed label only (reviewed name; no accession asserted)	CCT2	two copies per double-ring complex	UNKNOWN	One of the eight paralogous subunits that forms each hetero-octameric chaperonin-containing T-complex ring. `DOI:10.1038/emboj.2011.208` Dekker et al. 2011 solved the Saccharomyces cerevisiae CCT crystal structure and assigned Cct1p through Cct8p within its hetero-oligomeric rings. `PMID:8771707` Stoldt et al. 1996 reviewed CCT subunits in Saccharomyces cerevisiae and related yeasts.
CCT gamma subunit	Protein	part of	Reviewed label only (reviewed name; no accession asserted)	CCT3	two copies per double-ring complex	UNKNOWN	One of the eight paralogous subunits that forms each hetero-octameric chaperonin-containing T-complex ring. `DOI:10.1038/emboj.2011.208` Dekker et al. 2011 solved the Saccharomyces cerevisiae CCT crystal structure and assigned Cct1p through Cct8p within its hetero-oligomeric rings. `PMID:8771707` Stoldt et al. 1996 reviewed CCT subunits in Saccharomyces cerevisiae and related yeasts.
CCT delta subunit	Protein	part of	Reviewed label only (reviewed name; no accession asserted)	CCT4	two copies per double-ring complex	UNKNOWN	One of the eight paralogous subunits that forms each hetero-octameric chaperonin-containing T-complex ring. `DOI:10.1038/emboj.2011.208` Dekker et al. 2011 solved the Saccharomyces cerevisiae CCT crystal structure and assigned Cct1p through Cct8p within its hetero-oligomeric rings. `PMID:8771707` Stoldt et al. 1996 reviewed CCT subunits in Saccharomyces cerevisiae and related yeasts.
CCT epsilon subunit	Protein	part of	Reviewed label only (reviewed name; no accession asserted)	CCT5	two copies per double-ring complex	UNKNOWN	One of the eight paralogous subunits that forms each hetero-octameric chaperonin-containing T-complex ring. `DOI:10.1038/emboj.2011.208` Dekker et al. 2011 solved the Saccharomyces cerevisiae CCT crystal structure and assigned Cct1p through Cct8p within its hetero-oligomeric rings. `PMID:8771707` Stoldt et al. 1996 reviewed CCT subunits in Saccharomyces cerevisiae and related yeasts.
CCT zeta subunit	Protein	part of	Reviewed label only (reviewed name; no accession asserted)	CCT6	two copies per double-ring complex	UNKNOWN	One of the eight paralogous subunits that forms each hetero-octameric chaperonin-containing T-complex ring. `DOI:10.1038/emboj.2011.208` Dekker et al. 2011 solved the Saccharomyces cerevisiae CCT crystal structure and assigned Cct1p through Cct8p within its hetero-oligomeric rings. `PMID:8771707` Stoldt et al. 1996 reviewed CCT subunits in Saccharomyces cerevisiae and related yeasts.
CCT eta subunit	Protein	part of	Reviewed label only (reviewed name; no accession asserted)	CCT7	two copies per double-ring complex	UNKNOWN	One of the eight paralogous subunits that forms each hetero-octameric chaperonin-containing T-complex ring. `DOI:10.1038/emboj.2011.208` Dekker et al. 2011 solved the Saccharomyces cerevisiae CCT crystal structure and assigned Cct1p through Cct8p within its hetero-oligomeric rings. `PMID:8771707` Stoldt et al. 1996 reviewed CCT subunits in Saccharomyces cerevisiae and related yeasts.
CCT theta subunit	Protein	part of	Reviewed label only (reviewed name; no accession asserted)	CCT8	two copies per double-ring complex	UNKNOWN	One of the eight paralogous subunits that forms each hetero-octameric chaperonin-containing T-complex ring. `DOI:10.1038/emboj.2011.208` Dekker et al. 2011 solved the Saccharomyces cerevisiae CCT crystal structure and assigned Cct1p through Cct8p within its hetero-oligomeric rings. `PMID:8771707` Stoldt et al. 1996 reviewed CCT subunits in Saccharomyces cerevisiae and related yeasts.

Taxonomic distribution

NCBITaxon:4932 Saccharomyces cerevisiae — COMMON: Budding yeast contains a cytosolic CCT complex with Cct1p through Cct8p assigned in its double-ring crystal structure. [DOI:10.1038/emboj.2011.208]

Canonical examples

NCBITaxon:4932 Saccharomyces cerevisiae — Budding-yeast model whose CCT crystal structure resolved the positions of the Cct1p through Cct8p subunits. [DOI:10.1038/emboj.2011.208]

Functions

protein folding GO:0006457 — CCT assists ATP-dependent folding of newly synthesized cytosolic substrate proteins.
- GO:0005832 GO:0005832 defines CCT as a cytosolic complex that mediates protein folding.
- DOI:10.1006/jsbi.2001.4380 Dunn et al. 2001 reviewed cellular substrates of the eukaryotic chaperonin TRiC/CCT.

Mechanism graphs

Eight CCT subunits form cytosolic substrate-folding rings (FUNCTION)

CCT is built from eight paralogous subunits that assemble into cytosolic hetero-octameric rings and assist protein folding.

Subject	Predicate	Object	Evidence
CCT alpha subunit	assembles into	chaperonin-containing T-complex	`DOI:10.1038/emboj.2011.208` Dekker et al. 2011 assigned the eight Cct1p-Cct8p subunits in the yeast CCT structure.
CCT beta subunit	assembles into	chaperonin-containing T-complex	`DOI:10.1038/emboj.2011.208` Dekker et al. 2011 assigned the eight Cct1p-Cct8p subunits in the yeast CCT structure.
CCT gamma subunit	assembles into	chaperonin-containing T-complex	`DOI:10.1038/emboj.2011.208` Dekker et al. 2011 assigned the eight Cct1p-Cct8p subunits in the yeast CCT structure.
CCT delta subunit	assembles into	chaperonin-containing T-complex	`DOI:10.1038/emboj.2011.208` Dekker et al. 2011 assigned the eight Cct1p-Cct8p subunits in the yeast CCT structure.
CCT epsilon subunit	assembles into	chaperonin-containing T-complex	`DOI:10.1038/emboj.2011.208` Dekker et al. 2011 assigned the eight Cct1p-Cct8p subunits in the yeast CCT structure.
CCT zeta subunit	assembles into	chaperonin-containing T-complex	`DOI:10.1038/emboj.2011.208` Dekker et al. 2011 assigned the eight Cct1p-Cct8p subunits in the yeast CCT structure.
CCT eta subunit	assembles into	chaperonin-containing T-complex	`DOI:10.1038/emboj.2011.208` Dekker et al. 2011 assigned the eight Cct1p-Cct8p subunits in the yeast CCT structure.
CCT theta subunit	assembles into	chaperonin-containing T-complex	`DOI:10.1038/emboj.2011.208` Dekker et al. 2011 assigned the eight Cct1p-Cct8p subunits in the yeast CCT structure.
chaperonin-containing T-complex	is part of	cytosol	`GO:0005832` GO:0005832 defines CCT as mediating protein folding in the cytosol.
chaperonin-containing T-complex	supports	protein folding	`GO:0005832` GO:0005832 defines CCT by its protein folding role. `DOI:10.1006/jsbi.2001.4380` Dunn et al. 2001 reviewed substrate classes folded by the eukaryotic chaperonin TRiC/CCT.

Discussions

CURATION_TODO (OPEN): Resolve exact source-neutral CCT1-CCT8 paralogue family groundings for the reviewed label-only component rows. GO exactly grounds the chaperonin-containing T-complex and yeast structures assign the eight paralogous Cct1p through Cct8p constituents, but exact taxon-agnostic family identifiers for each subunit were not curated in this pass.

Evidence

GO:0005832 Gene Ontology cellular-component term for the chaperonin-containing T-complex.
GO:0032991 Gene Ontology cellular-component parent term for protein-containing complexes.
GO:0005829 — cytosol Gene Ontology cellular-component term for the cytosol, where GO locates CCT.
GO:0006457 Gene Ontology biological-process term for protein folding.
PMID:8771707 Stoldt et al. 1996, The Cct eukaryotic chaperonin subunits of Saccharomyces cerevisiae and other yeasts, Yeast.
DOI:10.1006/jsbi.2001.4380 Dunn, Melville and Frydman 2001, Review: cellular substrates of the eukaryotic chaperonin TRiC/CCT, Journal of Structural Biology.
DOI:10.1038/emboj.2011.208 Dekker et al. 2011, The crystal structure of yeast CCT reveals intrinsic asymmetry of eukaryotic cytosolic chaperonins, The EMBO Journal.

Curation history

2026-09-19T00:26:36Z codex · CREATED_RECORD — Scaffolded by scripts/new_record.py
2026-09-19T00:27:31Z codex · EXPANDED_RECORD — Added CCT/TRiC synonymy, protein-complex parentage, cytosolic parthood, CCT1-CCT8 component rows, eukaryotic scope, a protein-folding function, GO/PMID/DOI evidence, a nonmechanistic CCT folding graph, and a CCT subunit-grounding TODO.
2026-09-19T00:39:13Z codex · ADDRESS_REVIEW — Resolved #1211 by narrowing the taxonomic distribution to Saccharomyces cerevisiae and resolved #1212 by expressing CCT1-CCT8 stoichiometry per complete double-ring complex.

Source: data/structures/other/chaperonin_containing_t_complex.yaml