CCT3 encodes the gamma subunit of the cytosolic group II chaperonin TRiC/CCT. As one of eight obligate paralogous subunits in each ring, Cct3 contributes ATPase and substrate-contact surfaces to the hetero-oligomeric folding chamber that matures actin, tubulin, and other cytosolic clients. Its curated core function is complex-level ATP-dependent protein folding, not nonspecific protein binding.
| GO Term | Evidence | Action | Reason |
|---|---|---|---|
|
GO:0006457
protein folding
|
IBA
GO_REF:0000033 |
ACCEPT |
Summary: CCT3 participates in protein folding as an obligate subunit of TRiC/CCT, the cytosolic chaperonin that folds actin, tubulin, and other clients.
Reason: Protein folding is the correct biological-process context for the chaperonin complex, supported by direct yeast CCT actin-folding assays and PANTHER/InterPro family evidence.
Supporting Evidence:
file:yeast/CCT3/CCT3-deep-research-falcon.md
The CCT/TRiC complex is a double-ring ATP-driven folding machine
|
|
GO:0005832
chaperonin-containing T-complex
|
IBA
GO_REF:0000033 |
ACCEPT |
Summary: CCT3 is a named subunit of the chaperonin-containing T-complex.
Reason: Complex membership is central to the gene product function and is supported by yeast CCT complex literature and family evidence.
|
|
GO:0051082
unfolded protein binding
|
IBA
GO_REF:0000033 |
MODIFY |
Summary: unfolded protein binding reflects substrate engagement by TRiC/CCT, but it is less informative than the ATP-dependent folding chaperone function of the complex.
Reason: Replace generic substrate-binding language with the specific chaperonin activity supported by yeast CCT actin-folding assays and domain evidence.
Proposed replacements:
ATP-dependent protein folding chaperone
|
|
GO:0000166
nucleotide binding
|
IEA
GO_REF:0000043 |
MARK AS OVER ANNOTATED |
Summary: nucleotide binding is a true but overly broad family/keyword annotation for CCT3; ATP binding, ATP hydrolysis, and ATP-dependent chaperone annotations capture the specific chemistry.
Reason: Generic nucleotide binding does not add useful functional information beyond the more specific ATP-related chaperonin annotations already present.
|
|
GO:0005524
ATP binding
|
IEA
GO_REF:0000120 |
KEEP AS NON CORE |
Summary: CCT3 contains a conserved chaperonin ATP-binding site, but ATP binding alone is a domain property rather than the core biological function.
Reason: Keep as a valid supporting molecular property of the CCT ATPase cycle, while treating ATP hydrolysis and complex-level protein folding as the core function.
|
|
GO:0005737
cytoplasm
|
IEA
GO_REF:0000044 |
ACCEPT |
Summary: CCT3 functions as part of the cytosolic TRiC/CCT chaperonin.
Reason: Cytoplasm is the established location of the CCT/TRiC folding machine.
|
|
GO:0005832
chaperonin-containing T-complex
|
IEA
GO_REF:0000117 |
ACCEPT |
Summary: CCT3 is a named subunit of the chaperonin-containing T-complex.
Reason: Complex membership is central to the gene product function and is supported by yeast CCT complex literature and family evidence.
|
|
GO:0006457
protein folding
|
IEA
GO_REF:0000120 |
ACCEPT |
Summary: CCT3 participates in protein folding as an obligate subunit of TRiC/CCT, the cytosolic chaperonin that folds actin, tubulin, and other clients.
Reason: Protein folding is the correct biological-process context for the chaperonin complex, supported by direct yeast CCT actin-folding assays and PANTHER/InterPro family evidence.
|
|
GO:0016887
ATP hydrolysis activity
|
IEA
GO_REF:0000002 |
ACCEPT |
Summary: CCT3 is a TCP-1/CCT chaperonin subunit with conserved ATPase machinery that powers TRiC/CCT conformational cycling.
Reason: ATP hydrolysis is a defensible subunit-level molecular function for CCT family members and is directly tied to the chaperonin folding cycle.
|
|
GO:0051082
unfolded protein binding
|
IEA
GO_REF:0000120 |
MODIFY |
Summary: unfolded protein binding reflects substrate engagement by TRiC/CCT, but it is less informative than the ATP-dependent folding chaperone function of the complex.
Reason: Replace generic substrate-binding language with the specific chaperonin activity supported by yeast CCT actin-folding assays and domain evidence.
Proposed replacements:
ATP-dependent protein folding chaperone
|
|
GO:0140662
ATP-dependent protein folding chaperone
|
IEA
GO_REF:0000002 |
ACCEPT |
Summary: CCT3 is an obligate subunit of the ATP-dependent TRiC/CCT folding machine.
Reason: The term is appropriate as a complex-level chaperonin function; in the synthesized core function it is modeled as a contributed-to molecular function rather than a standalone activity of an isolated subunit.
Supporting Evidence:
PMID:16762366
The eukaryotic cytosolic chaperonin CCT is an essential ATP-dependent protein folding machine whose action is required for folding the cytoskeletal proteins actin and tubulin
|
|
GO:0005515
protein binding
|
IPI
PMID:19536198 An atlas of chaperone-protein interactions in Saccharomyces ... |
MARK AS OVER ANNOTATED |
Summary: protein binding is too generic for a CCT subunit and does not describe the chaperonin mechanism or substrate class.
Reason: Physical-interaction datasets are useful evidence context, but generic protein binding should not stand as a functional annotation when the specific TRiC/CCT chaperonin role is known.
Supporting Evidence:
PMID:19536198
It should be emphasized that the interactions presented are indirect TAP-tag based interactions and not direct binary interactions.
|
|
GO:0005515
protein binding
|
IPI
PMID:37968396 The social and structural architecture of the yeast protein ... |
MARK AS OVER ANNOTATED |
Summary: protein binding is too generic for a CCT subunit and does not describe the chaperonin mechanism or substrate class.
Reason: Physical-interaction datasets are useful evidence context, but generic protein binding should not stand as a functional annotation when the specific TRiC/CCT chaperonin role is known.
|
|
GO:0006457
protein folding
|
IDA
PMID:16762366 Quantitative actin folding reactions using yeast CCT purifie... |
ACCEPT |
Summary: CCT3 participates in protein folding as an obligate subunit of TRiC/CCT, the cytosolic chaperonin that folds actin, tubulin, and other clients.
Reason: Protein folding is the correct biological-process context for the chaperonin complex, supported by direct yeast CCT actin-folding assays and PANTHER/InterPro family evidence.
Supporting Evidence:
PMID:16762366
The eukaryotic cytosolic chaperonin CCT is an essential ATP-dependent protein folding machine whose action is required for folding the cytoskeletal proteins actin and tubulin
|
|
GO:0005832
chaperonin-containing T-complex
|
IPI
PMID:15704212 Physiological effects of unassembled chaperonin Cct subunits... |
ACCEPT |
Summary: CCT3 is a named subunit of the chaperonin-containing T-complex.
Reason: Complex membership is central to the gene product function and is supported by yeast CCT complex literature and family evidence.
Supporting Evidence:
PMID:16762366
The eukaryotic cytosolic chaperonin CCT is an essential ATP-dependent protein folding machine whose action is required for folding the cytoskeletal proteins actin and tubulin
|
|
GO:0005832
chaperonin-containing T-complex
|
IDA
PMID:16762366 Quantitative actin folding reactions using yeast CCT purifie... |
ACCEPT |
Summary: CCT3 is a named subunit of the chaperonin-containing T-complex.
Reason: Complex membership is central to the gene product function and is supported by yeast CCT complex literature and family evidence.
Supporting Evidence:
PMID:15704212
Eukaryotic chaperonins, the Cct complexes, are assembled into two rings, each of which is composed of a stoichiometric array of eight different subunits
|
|
GO:0051082
unfolded protein binding
|
IDA
PMID:16762366 Quantitative actin folding reactions using yeast CCT purifie... |
MODIFY |
Summary: unfolded protein binding reflects substrate engagement by TRiC/CCT, but it is less informative than the ATP-dependent folding chaperone function of the complex.
Reason: Replace generic substrate-binding language with the specific chaperonin activity supported by yeast CCT actin-folding assays and domain evidence.
Proposed replacements:
ATP-dependent protein folding chaperone
Supporting Evidence:
PMID:16762366
The eukaryotic cytosolic chaperonin CCT is an essential ATP-dependent protein folding machine whose action is required for folding the cytoskeletal proteins actin and tubulin
|
Q: Which yeast client proteins depend specifically on Cct3 apical-domain contacts rather than on generic TRiC/CCT chamber activity?
Experiment: Profile client aggregation, solubility, and folding reporter behavior in conditional CCT3 mutants under permissive and restrictive conditions, with actin and tubulin reporters as controls.
Hypothesis: Cct3 contributes subunit-specific contacts for a subset of aggregation-prone or Q/N-rich clients.
Type: conditional mutant proteostasis profiling
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template_variables:
organism: yeast
gene_id: CCT3
gene_symbol: CCT3
uniprot_accession: P39077
protein_description: 'RecName: Full=T-complex protein 1 subunit gamma; Short=TCP-1-gamma;
AltName: Full=CCT-gamma;'
gene_info: Name=CCT3; Synonyms=BIN2, TCP3; OrderedLocusNames=YJL014W; ORFNames=J1336;
organism_full: Saccharomyces cerevisiae (strain ATCC 204508 / S288c) (Baker's yeast).
protein_family: Belongs to the TCP-1 chaperonin family. .
protein_domains: Chap_CCT_gamma. (IPR012719); Chaperone_TCP-1. (IPR017998); Chaperonin_TCP-1_CS.
(IPR002194); Cpn60/GroEL/TCP-1. (IPR002423); GroEL-like_apical_dom_sf. (IPR027409)
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BEFORE YOU BEGIN RESEARCH: You MUST verify you are researching the CORRECT gene/protein. Gene symbols can be ambiguous, especially for less well-characterized genes from non-model organisms.
DO NOT PROCEED WITH RESEARCH ON A DIFFERENT GENE. Instead:
- State clearly: "The gene symbol 'CCT3' is ambiguous or literature is limited for this specific protein"
- Explain what you found (e.g., "Found extensive literature on a different gene with the same symbol in a different organism")
- Describe the protein based ONLY on the UniProt information provided above
- Suggest that the protein function can be inferred from domain/family information
Please provide a comprehensive research report on the gene CCT3 (gene ID: CCT3, UniProt: P39077) in yeast.
The research report should be a detailed narrative explaining the function, biological processes, and localization of the gene product. Citations should be given for all claims.
You should prioritize authoritative reviews and primary scientific literature when conducting research. You can supplement
this with annotations you find in gene/protein databases, but these can be outdated or inaccurate.
We are specifically interested in the primary function of the gene - for enzymes, what reaction is catalyzed, and what is the substrate specificity? For transporters, what is the substrate? For structural proteins or adapters, what is the broader structural role? For signaling molecules, what is the role in the pathway.
We are interested in where in or outside the cell the gene product carries out its function.
We are also interested in the signaling or biochemical pathways in which the gene functions. We are less interested in broad pleiotropic effects, except where these elucidate the precise role.
Include evidence where possible. We are interested in both experimental evidence as well as inference from structure, evolution, or bioinformatic analysis. Precise studies should be prioritized over high-throughput, where available.
Question: You are an expert researcher providing comprehensive, well-cited information.
Provide detailed information focusing on:
1. Key concepts and definitions with current understanding
2. Recent developments and latest research (prioritize 2023-2024 sources)
3. Current applications and real-world implementations
4. Expert opinions and analysis from authoritative sources
5. Relevant statistics and data from recent studies
Format as a comprehensive research report with proper citations. Include URLs and publication dates where available.
Always prioritize recent, authoritative sources and provide specific citations for all major claims.
BEFORE YOU BEGIN RESEARCH: You MUST verify you are researching the CORRECT gene/protein. Gene symbols can be ambiguous, especially for less well-characterized genes from non-model organisms.
DO NOT PROCEED WITH RESEARCH ON A DIFFERENT GENE. Instead:
- State clearly: "The gene symbol 'CCT3' is ambiguous or literature is limited for this specific protein"
- Explain what you found (e.g., "Found extensive literature on a different gene with the same symbol in a different organism")
- Describe the protein based ONLY on the UniProt information provided above
- Suggest that the protein function can be inferred from domain/family information
Please provide a comprehensive research report on the gene CCT3 (gene ID: CCT3, UniProt: P39077) in yeast.
The research report should be a detailed narrative explaining the function, biological processes, and localization of the gene product. Citations should be given for all claims.
You should prioritize authoritative reviews and primary scientific literature when conducting research. You can supplement
this with annotations you find in gene/protein databases, but these can be outdated or inaccurate.
We are specifically interested in the primary function of the gene - for enzymes, what reaction is catalyzed, and what is the substrate specificity? For transporters, what is the substrate? For structural proteins or adapters, what is the broader structural role? For signaling molecules, what is the role in the pathway.
We are interested in where in or outside the cell the gene product carries out its function.
We are also interested in the signaling or biochemical pathways in which the gene functions. We are less interested in broad pleiotropic effects, except where these elucidate the precise role.
Include evidence where possible. We are interested in both experimental evidence as well as inference from structure, evolution, or bioinformatic analysis. Precise studies should be prioritized over high-throughput, where available.
CCT3 encodes T-complex protein 1 subunit gamma (CCTγ; TRiC/CCT subunit 3), one of eight essential subunits comprising the eukaryotic cytosolic group II chaperonin CCT/TRiC. The CCT/TRiC complex is a double-ring ATP-driven folding machine that is required for proteostasis, including folding of key cytoskeletal proteins such as actin and tubulin. Yeast-specific evidence indicates that CCT3 has detectable subunit-specific client preferences, particularly affecting Q/N-rich proteins and P-body-associated proteins, and that perturbing CCT3 function produces broad stress sensitivities including ethanol and cell-wall integrity–associated phenotypes. (grantham2020themolecularchaperone pages 1-2, nadlerholly2012interactionsofsubunit pages 2-2, narayanan2016defectsinprotein pages 4-6)
The literature summarized here pertains to Saccharomyces cerevisiae (S288C) CCT3/YJL014W, encoding a subunit of the CCT/TRiC chaperonin complex. This is consistent with the UniProt description for P39077 as a TCP-1 chaperonin family member (CCTγ) and with yeast genetics studies that explicitly mutate CCT3 and assay phenotypes in yeast (e.g., CCT3 D91E; cct3-1). (nadlerholly2012interactionsofsubunit pages 2-2, narayanan2016defectsinprotein pages 2-4)
CCT/TRiC (chaperonin-containing TCP-1; tailless complex polypeptide 1 ring complex) is a eukaryotic ATP-dependent chaperonin. It is an obligate hetero-oligomer composed of two rings, each containing eight distinct subunits (commonly denoted CCT1–CCT8 or α–θ), generating a central chamber where client proteins fold. (grantham2020themolecularchaperone pages 1-2)
CCT3 is one of these eight distinct subunits. Structural/mechanistic work synthesized in the literature places CCT3 as part of a subunit pairing/grouping (e.g., CCT1–CCT3) and within a lower ATP-affinity hemisphere of the ring (CCT3/6/7/8) relative to a higher-affinity hemisphere (CCT1/2/4/5), implying subunit-specialized contributions to the ATPase cycle. (kelly2020structuralandfunctional pages 42-48)
CCT/TRiC operates via a coordinated ATPase-driven conformational cycle: substrate binds to apical domains, ATP binding/hydrolysis drives ring closure and encapsulation, and conformational changes promote folding. This general mechanism and architecture are described in authoritative reviews emphasizing the complex’s role as an essential proteostasis component. (grantham2020themolecularchaperone pages 1-2, que2024theroleof pages 1-2)
A mechanistic quantitative detail highlighted in structural/functional synthesis is that, on average, ~4 subunits per ring are occupied under saturating ATP, consistent with asymmetric ATP usage across subunits and supporting the view that not all subunits contribute equivalently to nucleotide binding/hydrolysis at a given time. CCT3 is categorized among lower ATP-affinity subunits in this model. (kelly2020structuralandfunctional pages 42-48)
CCT/TRiC is described as required for folding of the abundant cytoskeletal proteins actin and tubulin, which are central to microfilament and microtubule assembly. These clients are repeatedly treated as key/obligate substrates of the complex in reviews and in yeast stress-phenotype work that links impaired folding to cytoskeleton-mediated stress adaptation. (grantham2020themolecularchaperone pages 1-2, narayanan2016defectsinprotein pages 4-6)
A yeast-focused PNAS study directly probed subunit specialization using ATP-site mutations in CCT3 vs CCT6 and high-throughput microscopy. A CCT3 mutant (D91E; “MA3”) produced a strong, specific phenotype: dramatic accumulation of P-bodies, with multiple known P-body proteins forming prominent cytoplasmic puncta that colocalize with an established P-body marker. (nadlerholly2012interactionsofsubunit pages 2-2, nadlerholly2012interactionsofsubunit media 88c0bc6b)
Quantitatively, the same study reported that in MA3 relative to wild type, 46 proteins increased and 18 decreased at P < 0.01, and that the screen involved ~5,100 GFP-tagged strains, supporting a large-scale systematic assessment of proteome-level changes in a CCT3-perturbed background. (nadlerholly2012interactionsofsubunit pages 2-2)
The authors further concluded that subunit CCT3 shows a stronger in vivo interaction with Q/N-rich proteins than CCT6 and proposed that CCT3 contains features compatible with binding Q/N-rich segments, linking CCT3 activity to proteostasis of aggregation-prone regions commonly enriched in P-body components. (nadlerholly2012interactionsofsubunit pages 2-2, nadlerholly2012interactionsofsubunit pages 4-5)
CCT/TRiC is classically treated as a cytosolic chaperonin that acts on cytosolic proteins, consistent with its canonical substrates (actin/tubulin) and broad role in folding newly synthesized proteins. (grantham2020themolecularchaperone pages 1-2, que2024theroleof pages 1-2)
A 2024 yeast preprint reports that TRiC/CCT governs RNA polymerase II activity in the nucleus to support RNA homeostasis, indicating that in yeast the complex has functionally relevant nuclear activity beyond canonical cytosolic folding. The study used yeast TRiC purification and nuclear extract transcription assays (including 100 ng immobilized DNA template and 100 µg nuclear extract), supporting mechanistic investigation of nuclear transcription outputs in a TRiC-compromised condition (cct1-2). Although this is not CCT3-specific, it is a recent yeast development expanding the functional landscape in which CCT subunits operate. (gvozdenov2024triccctchaperoningoverns pages 30-33)
CCT/TRiC subunits are encoded by essential yeast genes, consistent with the central role of TRiC/CCT in folding core cellular proteins and maintaining homeostasis. (grantham2020themolecularchaperone pages 1-2)
A focused phenotyping study of yeast folding-machinery mutants reports that the cct3-1 mutant shows sensitivity to diverse stressors. In the authors’ categorical scoring, cct3-1 was sensitive/supersensitive across multiple conditions including ethanol, NaCl, DTT, arsenate, H2O2, SDS (cell-wall integrity proxy), and methanol, and was supersensitive to TBZ (a microtubule/actin-related stressor used in the study). (narayanan2016defectsinprotein pages 2-4)
The same work reports ethanol-specific findings: cct3-1 is noted as sensitive at 3% ethanol, and while all tested cct mutants failed to grow at 8% ethanol, many recovered tolerance to 6% ethanol by 48 h—with cct1 and cct3 mutants highlighted as exceptions in this recovery pattern. The authors also used Congo Red and zymolyase sensitivity and SEM morphology changes to support that defects in the folding machinery correlate with cell wall integrity defects, providing a plausible mechanistic link between CCT3 impairment, actin/cytoskeletal dysfunction, and cell-wall biosynthetic/maintenance pathways. (narayanan2016defectsinprotein pages 4-6)
The yeast CCT3 D91E mutant (MA3) triggers prominent P-body formation and altered abundance/localization of multiple P-body components; this is consistent with the hypothesis that CCT3 function supports folding/stability of specific aggregation-prone/QN-rich components that influence ribonucleoprotein granule formation. (nadlerholly2012interactionsofsubunit pages 2-2, nadlerholly2012interactionsofsubunit media 88c0bc6b)
CCT/TRiC is positioned as a major node in cellular proteostasis, supporting folding and suppressing aggregation, and it participates in protein biogenesis processes that intersect with translation. (grantham2020themolecularchaperone pages 1-2, que2024theroleof pages 1-2)
A 2024 review synthesizes evidence that CCT/TRiC has multiple roles related to translation elongation, including interacting with emerging peptides to protect them from aggregation/degradation and facilitating proper folding programs during protein synthesis. This provides a modern conceptual framework for interpreting CCT3 function as part of a chaperonin machine integrated with translation and nascent-chain quality control (even when the review is not yeast-exclusive). (que2024theroleof pages 1-2)
Que et al. (Heliyon; available online 1 Apr 2024) frame CCT/TRiC as an essential molecular chaperone in the elongation phase of eukaryotic translation and summarize how it contributes to maintaining balance among synthesis, folding, assembly, and degradation—an updated synthesis of field consensus relevant to interpreting yeast CCT3 phenotypes in conditions that stress protein biogenesis. URL: https://doi.org/10.1016/j.heliyon.2024.e29029 (que2024theroleof pages 1-2)
Gvozdenov et al. (bioRxiv; posted 26 Sep 2024) report that TRiC/CCT supports RNA polymerase II activity in the yeast nucleus, expanding the apparent functional reach of TRiC beyond canonical cytosolic folding and suggesting that TRiC perturbation can impact RNA homeostasis. URL: https://doi.org/10.1101/2024.09.26.615188 (gvozdenov2024triccctchaperoningoverns pages 30-33)
A 2023 structural study of TRiC-mediated tubulin folding reports that near-natively folded tubulin engages mainly with the CCT3/6/8 subunits through electrostatic/hydrophilic interactions in the closed chamber (in a human TRiC system). While not yeast-specific, this provides current mechanistic support for why CCT3 subunits can contribute specialized binding surfaces for key cytoskeletal clients—consistent with long-standing yeast genetics emphasizing actin/tubulin dependence on TRiC. URL: https://doi.org/10.1038/s42003-023-04915-x (gvozdenov2024triccctchaperoningoverns pages 33-36)
A practical implementation in yeast structural biology is the use of CCT3 as a subunit for internal tagging: Zang et al. (Scientific Reports; Feb 2018) describe a yeast internal-subunit eGFP labeling strategy (YISEL) and note purification of yeast CCT via an internal tag in the CCT3/γ subunit to enable cryo-EM subunit assignment. This is a concrete experimental application leveraging the endogenous yeast CCT3 locus. URL: https://doi.org/10.1038/s41598-017-18962-y (zang2018developmentofa pages 7-8)
Ethanol tolerance and cell wall integrity are central to industrial yeast performance. The observation that cct3-1 mutants show ethanol sensitivity and cell-wall-related phenotypes suggests that CCT3/TRiC integrity is a factor to consider in strain robustness under high-ethanol fermentations or other envelope-stressing conditions (noting that the cited study is phenotyping-focused rather than an industrial deployment report). URL: https://doi.org/10.1007/s00284-016-1024-x (narayanan2016defectsinprotein pages 4-6)
Microscopy and quantitative panels illustrating that CCT3 mutation (MA3) causes P-body accumulation and stronger Q/N-rich protein effects than a CCT6 mutant are shown in the retrieved figure crops from Nadler-Holly et al. (PNAS, 2012). (nadlerholly2012interactionsofsubunit media 88c0bc6b, nadlerholly2012interactionsofsubunit media 61c31059, nadlerholly2012interactionsofsubunit media 27997266)
| Aspect | Key points | Best supporting citations | Key source URLs+publication dates |
|---|---|---|---|
| identity/synonyms | • Verified target is Saccharomyces cerevisiae CCT3 / YJL014W, encoding the TRiC/CCT chaperonin subunit gamma (CCTγ). • CCT3 is one of the eight distinct paralogous subunits of the eukaryotic cytosolic chaperonin CCT/TRiC. • The literature also uses the CCT/TRiC-wide naming scheme CCT1–CCT8 / α–θ, so care is needed to avoid mixing with non-yeast CCT3 orthologs. | (grantham2020themolecularchaperone pages 1-2, gvozdenov2024triccctchaperoningoverns pages 33-36, kelly2020structuralandfunctional pages 42-48) | https://doi.org/10.3389/fgene.2020.00172 (Mar 2020); https://doi.org/10.1101/2024.09.26.615188 (Sep 26, 2024); https://doi.org/10.1073/pnas.1209277109 (Oct 2012) |
| complex | • CCT3 functions as a subunit of the CCT/TRiC hetero-oligomer, a barrel-shaped chaperonin with two rings of eight distinct subunits each. • Each subunit occupies a defined position within the ring. • Structural work places CCT3 in the CCT1–CCT3 apical-domain pair and in the low-ATP-affinity hemisphere (CCT3/6/7/8). | (grantham2020themolecularchaperone pages 1-2, kelly2020structuralandfunctional pages 42-48, zang2018developmentofa pages 7-8) | https://doi.org/10.3389/fgene.2020.00172 (Mar 2020); https://doi.org/10.1038/s41598-017-18962-y (Feb 2018) |
| mechanism | • CCT/TRiC is an ATP-dependent folding machine with substrate-binding apical domains and nucleotide-binding equatorial domains. • For CCT3 specifically, structural/functional characterization places it among the lower ATP-affinity subunits; under saturating ATP, an average of ~4 subunits per ring are occupied. • CCT3 contributes to the inter-ring interaction network via its N-terminus in models of ring closure. | (grantham2020themolecularchaperone pages 1-2, kelly2020structuralandfunctional pages 42-48) | https://doi.org/10.3389/fgene.2020.00172 (Mar 2020) |
| localization | • The strongest supported localization for the yeast complex is the cytosol/cytoplasm, consistent with its role folding newly made cytosolic proteins. • Recent yeast work also supports a nuclear role for TRiC/CCT in RNA polymerase II activity and RNA homeostasis, though this was shown for the complex rather than CCT3 specifically. • Older cited background also notes reports of association with Golgi membranes, nuclear matrix, and heterochromatin for CCT/TRiC literature more broadly. | (gvozdenov2024triccctchaperoningoverns pages 30-33, gvozdenov2024triccctchaperoningoverns pages 33-36, que2024theroleof pages 1-2) | https://doi.org/10.1101/2024.09.26.615188 (Sep 26, 2024); https://doi.org/10.1016/j.heliyon.2024.e29029 (Apr 1, 2024) |
| substrates/clients | • Canonical CCT/TRiC clients include actin and tubulin, described as major/obligate substrates of the complex. • A CCT3-specific yeast study found stronger interaction of CCT3 than CCT6 with Q/N-rich proteins, especially proteins linked to P-bodies. • In the CCT3 mutant screen, 46 proteins increased and 18 decreased relative to wild type, and 8 of 9 most-changed proteins had physical/genetic interactions with Q/N-rich proteins. | (nadlerholly2012interactionsofsubunit pages 2-2, grantham2020themolecularchaperone pages 1-2, nadlerholly2012interactionsofsubunit pages 4-5, nadlerholly2012interactionsofsubunit pages 5-6) | https://doi.org/10.1073/pnas.1209277109 (Oct 2012); https://doi.org/10.3389/fgene.2020.00172 (Mar 2020) |
| phenotypes | • Yeast CCT genes are essential, and the review literature states CCT subunits are encoded by essential yeast genes. • A CCT3 ATP-site mutant (D91E/MA3) caused strong P-body accumulation; several canonical P-body proteins formed prominent puncta, and the screen covered ~5,100 GFP-tagged strains. • In stress-phenotype work, cct3-1 showed sensitivity to multiple stressors including ethanol, NaCl, DTT, arsenate, H2O2, SDS, methanol, and was reported as supersensitive to TBZ; cct3-1 was sensitive at 3% ethanol, and cct3 mutants were among strains not recovering tolerance like most others by 48 h. | (nadlerholly2012interactionsofsubunit pages 2-2, grantham2020themolecularchaperone pages 1-2, narayanan2016defectsinprotein pages 2-4, narayanan2016defectsinprotein pages 4-6) | https://doi.org/10.1073/pnas.1209277109 (Oct 2012); https://doi.org/10.1007/s00284-016-1024-x (Mar 2016); https://doi.org/10.3389/fgene.2020.00172 (Mar 2020) |
| recent 2023-2024 developments | • A 2024 review emphasizes CCT/TRiC as an important regulator of translation elongation/protein synthesis coupling. • A 2023 structural study on TRiC-mediated tubulin folding captured a near-native folding intermediate engaging mainly CCT3/6/8 subunits in the closed chamber, supporting subunit-specialized substrate contacts. • A 2024 yeast preprint reports nuclear TRiC/CCT support of RNA polymerase II activity and RNA homeostasis. | (gvozdenov2024triccctchaperoningoverns pages 30-33, que2024theroleof pages 1-2) | https://doi.org/10.1016/j.heliyon.2024.e29029 (Apr 1, 2024); https://doi.org/10.1038/s42003-023-04915-x (May 2023); https://doi.org/10.1101/2024.09.26.615188 (Sep 26, 2024) |
| applications | • Yeast CCT3 has been used experimentally as an anchor for internal subunit eGFP labeling to map TRiC/CCT subunit arrangement in cryo-EM studies. • CCT/TRiC is used as a model system for studying proteostasis, aggregation control, and folding of complex proteins. • Stress-sensitive yeast cct mutants, including cct3-1, provide practical models for probing cell wall integrity and ethanol tolerance relevant to industrial/biotechnology contexts. | (zang2018developmentofa pages 7-8, grantham2020themolecularchaperone pages 1-2, narayanan2016defectsinprotein pages 4-6) | https://doi.org/10.1038/s41598-017-18962-y (Feb 2018); https://doi.org/10.3389/fgene.2020.00172 (Mar 2020); https://doi.org/10.1007/s00284-016-1024-x (Mar 2016) |
Table: This table summarizes the evidence-supported functional annotation of Saccharomyces cerevisiae CCT3/YJL014W, including complex membership, mechanism, localization, substrates, phenotypes, and recent developments. It is useful as a compact reference anchored to specific context IDs and source URLs.
References
(grantham2020themolecularchaperone pages 1-2): Julie Grantham. The molecular chaperone cct/tric: an essential component of proteostasis and a potential modulator of protein aggregation. Frontiers in Genetics, Mar 2020. URL: https://doi.org/10.3389/fgene.2020.00172, doi:10.3389/fgene.2020.00172. This article has 139 citations and is from a peer-reviewed journal.
(nadlerholly2012interactionsofsubunit pages 2-2): Michal Nadler-Holly, Michal Breker, Ranit Gruber, Ariel Azia, Melissa Gymrek, Miriam Eisenstein, Keith R. Willison, Maya Schuldiner, and Amnon Horovitz. Interactions of subunit cct3 in the yeast chaperonin cct/tric with q/n-rich proteins revealed by high-throughput microscopy analysis. Proceedings of the National Academy of Sciences, 109:18833-18838, Oct 2012. URL: https://doi.org/10.1073/pnas.1209277109, doi:10.1073/pnas.1209277109. This article has 52 citations and is from a highest quality peer-reviewed journal.
(narayanan2016defectsinprotein pages 4-6): Aswathy Narayanan, Dileep Pullepu, Praveen Kumar Reddy, Wasim Uddin, and M. Anaul Kabir. Defects in protein folding machinery affect cell wall integrity and reduce ethanol tolerance in s. cerevisiae. Current Microbiology, 73:38-45, Mar 2016. URL: https://doi.org/10.1007/s00284-016-1024-x, doi:10.1007/s00284-016-1024-x. This article has 7 citations and is from a peer-reviewed journal.
(narayanan2016defectsinprotein pages 2-4): Aswathy Narayanan, Dileep Pullepu, Praveen Kumar Reddy, Wasim Uddin, and M. Anaul Kabir. Defects in protein folding machinery affect cell wall integrity and reduce ethanol tolerance in s. cerevisiae. Current Microbiology, 73:38-45, Mar 2016. URL: https://doi.org/10.1007/s00284-016-1024-x, doi:10.1007/s00284-016-1024-x. This article has 7 citations and is from a peer-reviewed journal.
(kelly2020structuralandfunctional pages 42-48): J Kelly. Structural and functional characterisation of the group ii chaperonin cct/tric. Unknown journal, 2020.
(que2024theroleof pages 1-2): Yueyue Que, Yudan Qiu, Zheyu Ding, Shanshan Zhang, Rong Wei, Jianing Xia, and Yingying Lin. The role of molecular chaperone cct/tric in translation elongation: a literature review. Heliyon, 10:e29029, Apr 2024. URL: https://doi.org/10.1016/j.heliyon.2024.e29029, doi:10.1016/j.heliyon.2024.e29029. This article has 12 citations.
(nadlerholly2012interactionsofsubunit media 88c0bc6b): Michal Nadler-Holly, Michal Breker, Ranit Gruber, Ariel Azia, Melissa Gymrek, Miriam Eisenstein, Keith R. Willison, Maya Schuldiner, and Amnon Horovitz. Interactions of subunit cct3 in the yeast chaperonin cct/tric with q/n-rich proteins revealed by high-throughput microscopy analysis. Proceedings of the National Academy of Sciences, 109:18833-18838, Oct 2012. URL: https://doi.org/10.1073/pnas.1209277109, doi:10.1073/pnas.1209277109. This article has 52 citations and is from a highest quality peer-reviewed journal.
(nadlerholly2012interactionsofsubunit pages 4-5): Michal Nadler-Holly, Michal Breker, Ranit Gruber, Ariel Azia, Melissa Gymrek, Miriam Eisenstein, Keith R. Willison, Maya Schuldiner, and Amnon Horovitz. Interactions of subunit cct3 in the yeast chaperonin cct/tric with q/n-rich proteins revealed by high-throughput microscopy analysis. Proceedings of the National Academy of Sciences, 109:18833-18838, Oct 2012. URL: https://doi.org/10.1073/pnas.1209277109, doi:10.1073/pnas.1209277109. This article has 52 citations and is from a highest quality peer-reviewed journal.
(gvozdenov2024triccctchaperoningoverns pages 30-33): Zlata Gvozdenov, Audrey Yi Tyan Peng, Anusmita Biswas, Zeno Barcutean, Daniel Gestaut, Judith Frydman, Kevin Struhl, and Brian C. Freeman. Tric/cct chaperonin governs rna polymerase ii activity in the nucleus to support rna homeostasis. bioRxiv, Sep 2024. URL: https://doi.org/10.1101/2024.09.26.615188, doi:10.1101/2024.09.26.615188. This article has 3 citations.
(gvozdenov2024triccctchaperoningoverns pages 33-36): Zlata Gvozdenov, Audrey Yi Tyan Peng, Anusmita Biswas, Zeno Barcutean, Daniel Gestaut, Judith Frydman, Kevin Struhl, and Brian C. Freeman. Tric/cct chaperonin governs rna polymerase ii activity in the nucleus to support rna homeostasis. bioRxiv, Sep 2024. URL: https://doi.org/10.1101/2024.09.26.615188, doi:10.1101/2024.09.26.615188. This article has 3 citations.
(zang2018developmentofa pages 7-8): Yunxiang Zang, Huping Wang, Zhicheng Cui, Mingliang Jin, Caixuan Liu, Wenyu Han, Yanxing Wang, and Yao Cong. Development of a yeast internal-subunit egfp labeling strategy and its application in subunit identification in eukaryotic group ii chaperonin tric/cct. Scientific Reports, Feb 2018. URL: https://doi.org/10.1038/s41598-017-18962-y, doi:10.1038/s41598-017-18962-y. This article has 22 citations and is from a peer-reviewed journal.
(nadlerholly2012interactionsofsubunit media 61c31059): Michal Nadler-Holly, Michal Breker, Ranit Gruber, Ariel Azia, Melissa Gymrek, Miriam Eisenstein, Keith R. Willison, Maya Schuldiner, and Amnon Horovitz. Interactions of subunit cct3 in the yeast chaperonin cct/tric with q/n-rich proteins revealed by high-throughput microscopy analysis. Proceedings of the National Academy of Sciences, 109:18833-18838, Oct 2012. URL: https://doi.org/10.1073/pnas.1209277109, doi:10.1073/pnas.1209277109. This article has 52 citations and is from a highest quality peer-reviewed journal.
(nadlerholly2012interactionsofsubunit media 27997266): Michal Nadler-Holly, Michal Breker, Ranit Gruber, Ariel Azia, Melissa Gymrek, Miriam Eisenstein, Keith R. Willison, Maya Schuldiner, and Amnon Horovitz. Interactions of subunit cct3 in the yeast chaperonin cct/tric with q/n-rich proteins revealed by high-throughput microscopy analysis. Proceedings of the National Academy of Sciences, 109:18833-18838, Oct 2012. URL: https://doi.org/10.1073/pnas.1209277109, doi:10.1073/pnas.1209277109. This article has 52 citations and is from a highest quality peer-reviewed journal.
(nadlerholly2012interactionsofsubunit pages 5-6): Michal Nadler-Holly, Michal Breker, Ranit Gruber, Ariel Azia, Melissa Gymrek, Miriam Eisenstein, Keith R. Willison, Maya Schuldiner, and Amnon Horovitz. Interactions of subunit cct3 in the yeast chaperonin cct/tric with q/n-rich proteins revealed by high-throughput microscopy analysis. Proceedings of the National Academy of Sciences, 109:18833-18838, Oct 2012. URL: https://doi.org/10.1073/pnas.1209277109, doi:10.1073/pnas.1209277109. This article has 52 citations and is from a highest quality peer-reviewed journal.
id: P39077
gene_symbol: CCT3
product_type: PROTEIN
status: COMPLETE
taxon:
id: NCBITaxon:559292
label: Saccharomyces cerevisiae
description: >-
CCT3 encodes the gamma subunit of the cytosolic group II chaperonin TRiC/CCT. As one of eight obligate
paralogous subunits in each ring, Cct3 contributes ATPase and substrate-contact surfaces to the hetero-oligomeric
folding chamber that matures actin, tubulin, and other cytosolic clients. Its curated core function
is complex-level ATP-dependent protein folding, not nonspecific protein binding.
references:
- id: GO_REF:0000002
title: Gene Ontology annotation through association of InterPro records with GO terms
findings: []
- id: GO_REF:0000033
title: Annotation inferences using phylogenetic trees
findings: []
- id: GO_REF:0000043
title: Gene Ontology annotation based on UniProtKB/Swiss-Prot keyword mapping
findings: []
- id: GO_REF:0000044
title: >-
Gene Ontology annotation based on UniProtKB/Swiss-Prot Subcellular Location vocabulary mapping, accompanied
by conservative changes to GO terms applied by UniProt
findings: []
- id: GO_REF:0000117
title: Electronic Gene Ontology annotations created by ARBA machine learning models
findings: []
- id: GO_REF:0000120
title: Combined Automated Annotation using Multiple IEA Methods
findings: []
- id: PMID:15704212
title: Physiological effects of unassembled chaperonin Cct subunits in the yeast Saccharomyces cerevisiae.
findings:
- statement: Yeast CCT is a double-ring complex with a stoichiometric set of eight distinct Cct subunits.
supporting_text: >-
Eukaryotic chaperonins, the Cct complexes, are assembled into two rings, each of which is composed
of a stoichiometric array of eight different subunits
- id: PMID:16762366
title: >-
Quantitative actin folding reactions using yeast CCT purified via an internal tag in the CCT3/gamma
subunit.
findings:
- statement: >-
Purified yeast CCT, tagged through CCT3, catalyzes ATP-dependent actin folding; this supports protein-folding
and chaperonin activity annotations for CCT3 as a TRiC/CCT subunit.
supporting_text: >-
The eukaryotic cytosolic chaperonin CCT is an essential ATP-dependent protein folding machine whose
action is required for folding the cytoskeletal proteins actin and tubulin
- id: PMID:19536198
title: >-
An atlas of chaperone-protein interactions in Saccharomyces cerevisiae: implications to protein folding
pathways in the cell.
findings:
- statement: >-
The chaperone interactome study is useful context for CCT contacts but reports indirect TAP-tag
interactions rather than a specific molecular activity.
supporting_text: >-
It should be emphasized that the interactions presented are indirect TAP-tag based interactions
and not direct binary interactions.
- id: PMID:37968396
title: The social and structural architecture of the yeast protein interactome.
findings: []
- id: file:yeast/CCT3/CCT3-deep-research-falcon.md
title: Falcon deep research report for CCT3
findings:
- statement: >-
The Falcon report was reviewed and synthesized into the CCT3 curation, including core-function framing,
family/PANTHER context, and evidence limitations.
existing_annotations:
- term:
id: GO:0006457
label: protein folding
qualifier: involved_in
evidence_type: IBA
original_reference_id: GO_REF:0000033
review:
summary: >-
CCT3 participates in protein folding as an obligate subunit of TRiC/CCT, the cytosolic chaperonin
that folds actin, tubulin, and other clients.
action: ACCEPT
reason: >-
Protein folding is the correct biological-process context for the chaperonin complex, supported
by direct yeast CCT actin-folding assays and PANTHER/InterPro family evidence.
supported_by:
- reference_id: file:yeast/CCT3/CCT3-deep-research-falcon.md
supporting_text: The CCT/TRiC complex is a double-ring ATP-driven folding machine
- term:
id: GO:0005832
label: chaperonin-containing T-complex
qualifier: part_of
evidence_type: IBA
original_reference_id: GO_REF:0000033
review:
summary: CCT3 is a named subunit of the chaperonin-containing T-complex.
action: ACCEPT
reason: >-
Complex membership is central to the gene product function and is supported by yeast CCT complex
literature and family evidence.
- term:
id: GO:0051082
label: unfolded protein binding
qualifier: enables
evidence_type: IBA
original_reference_id: GO_REF:0000033
review:
summary: >-
unfolded protein binding reflects substrate engagement by TRiC/CCT, but it is less informative than
the ATP-dependent folding chaperone function of the complex.
action: MODIFY
reason: >-
Replace generic substrate-binding language with the specific chaperonin activity supported by yeast
CCT actin-folding assays and domain evidence.
proposed_replacement_terms:
- id: GO:0140662
label: ATP-dependent protein folding chaperone
- term:
id: GO:0000166
label: nucleotide binding
qualifier: enables
evidence_type: IEA
original_reference_id: GO_REF:0000043
review:
summary: >-
nucleotide binding is a true but overly broad family/keyword annotation for CCT3; ATP binding, ATP
hydrolysis, and ATP-dependent chaperone annotations capture the specific chemistry.
action: MARK_AS_OVER_ANNOTATED
reason: >-
Generic nucleotide binding does not add useful functional information beyond the more specific ATP-related
chaperonin annotations already present.
- term:
id: GO:0005524
label: ATP binding
qualifier: enables
evidence_type: IEA
original_reference_id: GO_REF:0000120
review:
summary: >-
CCT3 contains a conserved chaperonin ATP-binding site, but ATP binding alone is a domain property
rather than the core biological function.
action: KEEP_AS_NON_CORE
reason: >-
Keep as a valid supporting molecular property of the CCT ATPase cycle, while treating ATP hydrolysis
and complex-level protein folding as the core function.
- term:
id: GO:0005737
label: cytoplasm
qualifier: located_in
evidence_type: IEA
original_reference_id: GO_REF:0000044
review:
summary: CCT3 functions as part of the cytosolic TRiC/CCT chaperonin.
action: ACCEPT
reason: Cytoplasm is the established location of the CCT/TRiC folding machine.
- term:
id: GO:0005832
label: chaperonin-containing T-complex
qualifier: part_of
evidence_type: IEA
original_reference_id: GO_REF:0000117
review:
summary: CCT3 is a named subunit of the chaperonin-containing T-complex.
action: ACCEPT
reason: >-
Complex membership is central to the gene product function and is supported by yeast CCT complex
literature and family evidence.
- term:
id: GO:0006457
label: protein folding
qualifier: involved_in
evidence_type: IEA
original_reference_id: GO_REF:0000120
review:
summary: >-
CCT3 participates in protein folding as an obligate subunit of TRiC/CCT, the cytosolic chaperonin
that folds actin, tubulin, and other clients.
action: ACCEPT
reason: >-
Protein folding is the correct biological-process context for the chaperonin complex, supported
by direct yeast CCT actin-folding assays and PANTHER/InterPro family evidence.
- term:
id: GO:0016887
label: ATP hydrolysis activity
qualifier: enables
evidence_type: IEA
original_reference_id: GO_REF:0000002
review:
summary: >-
CCT3 is a TCP-1/CCT chaperonin subunit with conserved ATPase machinery that powers TRiC/CCT conformational
cycling.
action: ACCEPT
reason: >-
ATP hydrolysis is a defensible subunit-level molecular function for CCT family members and is directly
tied to the chaperonin folding cycle.
- term:
id: GO:0051082
label: unfolded protein binding
qualifier: enables
evidence_type: IEA
original_reference_id: GO_REF:0000120
review:
summary: >-
unfolded protein binding reflects substrate engagement by TRiC/CCT, but it is less informative than
the ATP-dependent folding chaperone function of the complex.
action: MODIFY
reason: >-
Replace generic substrate-binding language with the specific chaperonin activity supported by yeast
CCT actin-folding assays and domain evidence.
proposed_replacement_terms:
- id: GO:0140662
label: ATP-dependent protein folding chaperone
- term:
id: GO:0140662
label: ATP-dependent protein folding chaperone
qualifier: enables
evidence_type: IEA
original_reference_id: GO_REF:0000002
review:
summary: CCT3 is an obligate subunit of the ATP-dependent TRiC/CCT folding machine.
action: ACCEPT
reason: >-
The term is appropriate as a complex-level chaperonin function; in the synthesized core function
it is modeled as a contributed-to molecular function rather than a standalone activity of an isolated
subunit.
supported_by:
- reference_id: PMID:16762366
supporting_text: >-
The eukaryotic cytosolic chaperonin CCT is an essential ATP-dependent protein folding machine
whose action is required for folding the cytoskeletal proteins actin and tubulin
reference_section_type: ABSTRACT
- term:
id: GO:0005515
label: protein binding
qualifier: enables
evidence_type: IPI
original_reference_id: PMID:19536198
supporting_entities:
- UniProtKB:P32324
review:
summary: >-
protein binding is too generic for a CCT subunit and does not describe the chaperonin mechanism
or substrate class.
action: MARK_AS_OVER_ANNOTATED
reason: >-
Physical-interaction datasets are useful evidence context, but generic protein binding should not
stand as a functional annotation when the specific TRiC/CCT chaperonin role is known.
supported_by:
- reference_id: PMID:19536198
supporting_text: >-
It should be emphasized that the interactions presented are indirect TAP-tag based interactions
and not direct binary interactions.
- term:
id: GO:0005515
label: protein binding
qualifier: enables
evidence_type: IPI
original_reference_id: PMID:37968396
supporting_entities:
- UniProtKB:P32324
review:
summary: >-
protein binding is too generic for a CCT subunit and does not describe the chaperonin mechanism
or substrate class.
action: MARK_AS_OVER_ANNOTATED
reason: >-
Physical-interaction datasets are useful evidence context, but generic protein binding should not
stand as a functional annotation when the specific TRiC/CCT chaperonin role is known.
- term:
id: GO:0006457
label: protein folding
qualifier: involved_in
evidence_type: IDA
original_reference_id: PMID:16762366
review:
summary: >-
CCT3 participates in protein folding as an obligate subunit of TRiC/CCT, the cytosolic chaperonin
that folds actin, tubulin, and other clients.
action: ACCEPT
reason: >-
Protein folding is the correct biological-process context for the chaperonin complex, supported
by direct yeast CCT actin-folding assays and PANTHER/InterPro family evidence.
supported_by:
- reference_id: PMID:16762366
supporting_text: >-
The eukaryotic cytosolic chaperonin CCT is an essential ATP-dependent protein folding machine
whose action is required for folding the cytoskeletal proteins actin and tubulin
reference_section_type: ABSTRACT
- term:
id: GO:0005832
label: chaperonin-containing T-complex
qualifier: part_of
evidence_type: IPI
original_reference_id: PMID:15704212
supporting_entities:
- SGD:S000002596
review:
summary: CCT3 is a named subunit of the chaperonin-containing T-complex.
action: ACCEPT
reason: >-
Complex membership is central to the gene product function and is supported by yeast CCT complex
literature and family evidence.
supported_by:
- reference_id: PMID:16762366
supporting_text: >-
The eukaryotic cytosolic chaperonin CCT is an essential ATP-dependent protein folding machine
whose action is required for folding the cytoskeletal proteins actin and tubulin
reference_section_type: ABSTRACT
- term:
id: GO:0005832
label: chaperonin-containing T-complex
qualifier: part_of
evidence_type: IDA
original_reference_id: PMID:16762366
review:
summary: CCT3 is a named subunit of the chaperonin-containing T-complex.
action: ACCEPT
reason: >-
Complex membership is central to the gene product function and is supported by yeast CCT complex
literature and family evidence.
supported_by:
- reference_id: PMID:15704212
supporting_text: >-
Eukaryotic chaperonins, the Cct complexes, are assembled into two rings, each of which is composed
of a stoichiometric array of eight different subunits
reference_section_type: ABSTRACT
- term:
id: GO:0051082
label: unfolded protein binding
qualifier: enables
evidence_type: IDA
original_reference_id: PMID:16762366
review:
summary: >-
unfolded protein binding reflects substrate engagement by TRiC/CCT, but it is less informative than
the ATP-dependent folding chaperone function of the complex.
action: MODIFY
reason: >-
Replace generic substrate-binding language with the specific chaperonin activity supported by yeast
CCT actin-folding assays and domain evidence.
proposed_replacement_terms:
- id: GO:0140662
label: ATP-dependent protein folding chaperone
supported_by:
- reference_id: PMID:16762366
supporting_text: >-
The eukaryotic cytosolic chaperonin CCT is an essential ATP-dependent protein folding machine
whose action is required for folding the cytoskeletal proteins actin and tubulin
reference_section_type: ABSTRACT
core_functions:
- description: >-
CCT3 is the gamma subunit of the cytosolic TRiC/CCT chaperonin. The subunit contributes ATPase and
substrate-contact surfaces to the hetero-oligomeric double-ring complex, whose ATP-dependent conformational
cycle folds actin, tubulin, and other cytosolic client proteins. The synthesized function is modeled
as subunit ATP hydrolysis contributing to the complex-level ATP-dependent protein folding chaperone
activity.
molecular_function:
id: GO:0016887
label: ATP hydrolysis activity
contributes_to_molecular_function:
id: GO:0140662
label: ATP-dependent protein folding chaperone
directly_involved_in:
- id: GO:0006457
label: protein folding
locations:
- id: GO:0005737
label: cytoplasm
in_complex:
id: GO:0005832
label: chaperonin-containing T-complex
supported_by:
- reference_id: PMID:16762366
supporting_text: >-
The eukaryotic cytosolic chaperonin CCT is an essential ATP-dependent protein folding machine whose
action is required for folding the cytoskeletal proteins actin and tubulin
reference_section_type: ABSTRACT
- reference_id: PMID:15704212
supporting_text: >-
Eukaryotic chaperonins, the Cct complexes, are assembled into two rings, each of which is composed
of a stoichiometric array of eight different subunits
reference_section_type: ABSTRACT
suggested_questions:
- question: >-
Which yeast client proteins depend specifically on Cct3 apical-domain contacts rather than on generic
TRiC/CCT chamber activity?
suggested_experiments:
- hypothesis: Cct3 contributes subunit-specific contacts for a subset of aggregation-prone or Q/N-rich
clients.
description: >-
Profile client aggregation, solubility, and folding reporter behavior in conditional CCT3 mutants
under permissive and restrictive conditions, with actin and tubulin reporters as controls.
experiment_type: conditional mutant proteostasis profiling