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protein_domains: Chap_CCT_theta. (IPR012721); Chaperone_TCP-1. (IPR017998); Chaperonin_TCP-1_CS.
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Question

Gene Research for Functional Annotation

⚠️ CRITICAL: Gene/Protein Identification Context

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.

Target Gene/Protein Identity (from UniProt):

• UniProt Accession: P47079
• Protein Description: RecName: Full=T-complex protein 1 subunit theta; Short=TCP-1-theta; AltName: Full=CCT-theta;
• Gene Information: Name=CCT8; OrderedLocusNames=YJL008C; ORFNames=J1374;
• Organism (full): Saccharomyces cerevisiae (strain ATCC 204508 / S288c) (Baker's yeast).
• Protein Family: Belongs to the TCP-1 chaperonin family. .
• Key Domains: Chap_CCT_theta. (IPR012721); Chaperone_TCP-1. (IPR017998); Chaperonin_TCP-1_CS. (IPR002194); Cpn60/GroEL/TCP-1. (IPR002423); GroEL-like_apical_dom_sf. (IPR027409)

MANDATORY VERIFICATION STEPS:

1. Check if the gene symbol "CCT8" matches the protein description above
2. Verify the organism is correct: Saccharomyces cerevisiae (strain ATCC 204508 / S288c) (Baker's yeast).
3. Check if protein family/domains align with what you find in literature
4. If you find literature for a DIFFERENT gene with the same or similar symbol, STOP

If Gene Symbol is Ambiguous or You Cannot Find Relevant Literature:

DO NOT PROCEED WITH RESEARCH ON A DIFFERENT GENE. Instead:
- State clearly: "The gene symbol 'CCT8' 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

Research Target:

Please provide a comprehensive research report on the gene CCT8 (gene ID: CCT8, UniProt: P47079) 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this with annotations you find in gene/protein databases, but these can be outdated or inaccurate.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.

Output

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.

Gene Research for Functional Annotation

⚠️ CRITICAL: Gene/Protein Identification Context

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.

Target Gene/Protein Identity (from UniProt):

• UniProt Accession: P47079
• Protein Description: RecName: Full=T-complex protein 1 subunit theta; Short=TCP-1-theta; AltName: Full=CCT-theta;
• Gene Information: Name=CCT8; OrderedLocusNames=YJL008C; ORFNames=J1374;
• Organism (full): Saccharomyces cerevisiae (strain ATCC 204508 / S288c) (Baker's yeast).
• Protein Family: Belongs to the TCP-1 chaperonin family. .
• Key Domains: Chap_CCT_theta. (IPR012721); Chaperone_TCP-1. (IPR017998); Chaperonin_TCP-1_CS. (IPR002194); Cpn60/GroEL/TCP-1. (IPR002423); GroEL-like_apical_dom_sf. (IPR027409)

MANDATORY VERIFICATION STEPS:

1. Check if the gene symbol "CCT8" matches the protein description above
2. Verify the organism is correct: Saccharomyces cerevisiae (strain ATCC 204508 / S288c) (Baker's yeast).
3. Check if protein family/domains align with what you find in literature
4. If you find literature for a DIFFERENT gene with the same or similar symbol, STOP

If Gene Symbol is Ambiguous or You Cannot Find Relevant Literature:

DO NOT PROCEED WITH RESEARCH ON A DIFFERENT GENE. Instead:
- State clearly: "The gene symbol 'CCT8' 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

Research Target:

Please provide a comprehensive research report on the gene CCT8 (gene ID: CCT8, UniProt: P47079) 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.

Research report: Functional annotation of Saccharomyces cerevisiae CCT8 (UniProt P47079; ORF YJL008C)

Executive summary

CCT8 (systematic name YJL008C) encodes T-complex protein 1 subunit theta (Cct8p/CCTθ), an essential subunit of the cytosolic TRiC/CCT (chaperonin-containing TCP-1) group II chaperonin in budding yeast. Genetic null alleles are lethal, consistent with Cct8p’s role as a required structural component of the hetero-oligomeric folding machine that supports cytoskeletal biogenesis (especially actin folding and microtubule assembly) and broader proteostasis. Quantitative proteomics places Cct8p at ~6,000 molecules/cell, and proteome-scale flux estimates indicate chaperone networks mediate folding of most newly synthesized protein molecules, with CCT contributing a smaller but essential share. Recent (2023–2024) cryo-EM and crosslinking studies of TRiC (primarily in mammalian systems) have sharpened subunit-specific models, explicitly placing CCT8 among the subunits that contact key obligate clients (tubulin) and client/co-chaperone assemblies (actin/PhLP2A), providing mechanistic context that informs interpretation of yeast Cct8p function and subunit specialization. (esser1999disruptionofsix pages 1-3, esser1999disruptionofsix pages 8-10, brownridge2013quantitativeanalysisof pages 5-6, brownridge2013quantitativeanalysisof pages 11-12, liu2023pathwayandmechanism pages 3-4, junsun2024astructuralvista pages 1-2)

1) Identity verification (critical disambiguation)

Target identity matches the UniProt context provided. A yeast chromosome X disruption study explicitly annotates YJL008C (gene symbol CCT8) and describes it as a cytosolic TRiC/CCT subunit (a “TCP ring complex” component). (Esser et al., 1999, Yeast, Jul 1999; https://doi.org/10.1002/(sici)1097-0061(199907)15:10b<921::aid-yea389>3.0.co;2-6) (esser1999disruptionofsix pages 1-3, esser1999disruptionofsix pages 8-10)

An authoritative yeast-focused review also maps CCT8 ↔ YJL008C in its gene table, supporting the ORF-to-gene correspondence. (Stoldt et al., 1996, Yeast, May 1996; https://doi.org/10.1002/(sici)1097-0061(199605)12:6<523::aid-yea962>3.0.co;2-c) (stoldt1996reviewthecct pages 1-2)

Scope note: The symbol CCT8 is also used for orthologous subunits in humans and other eukaryotes. In this report, non-yeast studies are cited only to explain conserved TRiC/CCT mechanisms and subunit-specific principles, not as direct evidence of S. cerevisiae phenotypes unless explicitly general. (liu2023pathwayandmechanism pages 3-4, junsun2024astructuralvista pages 1-2)

2) Key concepts and definitions (current understanding)

2.1 TRiC/CCT as a eukaryotic group II chaperonin

TRiC/CCT is a ~1 MDa cytosolic, ATP-dependent chaperonin that promotes folding of non-native proteins by encapsulating them within a central chamber and cycling between open and closed conformational states driven by ATP binding and hydrolysis. Each ring contains eight distinct paralogous subunits (CCT1–CCT8) arranged in a fixed order; the complex is composed of two opposed rings (16 subunits total). (Wilkinson et al., 2022, Frontiers in Molecular Biosciences, Dec 2022; https://doi.org/10.3389/fmolb.2022.1057232; Que et al., 2024, Heliyon, Apr 2024; https://doi.org/10.1016/j.heliyon.2024.e29029) (wilkinson2022themalariaparasite pages 1-2, que2024theroleof pages 2-4)

Each subunit comprises an equatorial domain (ATP binding and ring interfaces), intermediate domain, and apical domain (substrate-binding surface), consistent with a conserved chaperonin architecture. (Wilkinson et al., 2022; Que et al., 2024) (wilkinson2022themalariaparasite pages 1-2, que2024theroleof pages 2-4)

2.2 What “functional annotation” means for a chaperonin subunit

Cct8p is not an enzyme catalyzing a specific chemical reaction. Instead, its primary molecular function is as a structural and functional subunit of the TRiC/CCT folding machine, contributing to chamber formation, client binding surfaces, inter-ring contacts, and coordinated conformational cycling required for productive client folding. (esser1999disruptionofsix pages 8-10, kelly2020structuralandfunctionala pages 42-48)

3) Yeast CCT8: molecular function, processes, and pathways

3.1 Molecular function and biological role

A yeast gene-disruption study explicitly states that CCT8 (YJL008C) encodes a subunit of the heterooligomeric chaperonin TCP ring complex (TRiC/CCT) in the cytosol and that it is required for microtubule assembly and actin folding (and possibly other proteins). (Esser et al., 1999, Yeast, Jul 1999; https://doi.org/10.1002/(sici)1097-0061(199907)15:10b<921::aid-yea389>3.0.co;2-6) (esser1999disruptionofsix pages 8-10)

A yeast review similarly summarizes that Cct/TRiC is required for assembly of microtubules and actin in vivo, consistent with the core cytoskeletal role of the complex. (Stoldt et al., 1996, Yeast, May 1996; https://doi.org/10.1002/(sici)1097-0061(199605)12:6<523::aid-yea962>3.0.co;2-c) (stoldt1996reviewthecct pages 1-2)

3.2 Subcellular localization

CCT8/TRiC is described as localized in the cytosol of eukaryotes. (Esser et al., 1999) (esser1999disruptionofsix pages 8-10)

More broadly, CCT/TRiC is characterized as an ATP-dependent cytosolic chaperonin across eukaryotes, supporting the expectation that yeast Cct8p functions in cytosolic proteostasis rather than within secretory organelles. (Wilkinson et al., 2022) (wilkinson2022themalariaparasite pages 1-2)

3.3 Essentiality and phenotypes

CCT8/YJL008C is essential for viability in budding yeast. In tetrad analysis of a diploid heterozygous disruption, deletion of YJL008C showed 2:0 segregation of viability, indicating lethality. (Esser et al., 1999) (esser1999disruptionofsix pages 1-3, esser1999disruptionofsix pages 8-10)

The same study reports that spores bearing the deletion arrest growth after ~3 days, producing a very small microcolony (two cells) with a single bud, consistent with early essential failure of cytosolic proteostasis/cytoskeletal function. (Esser et al., 1999) (esser1999disruptionofsix pages 8-10)

A systems-level statement from an integrative review similarly asserts that all eight CCT genes are essential in yeast, consistent with CCT8’s essentiality as one of the eight subunits per ring. (Willison, 2018, Philosophical Transactions B, Jun 2018; https://doi.org/10.1098/rstb.2017.0192) (willison2018thesubstratespecificity pages 2-3)

3.4 Subunit specialization and inferred CCT8 sub-roles within TRiC

Although yeast genetics show CCT8 is essential as a subunit, structural/biophysical work suggests subunits differ in ATP usage and mechanical contribution. A yeast TRiC structural analysis classifies CCT8 in a low-ATP-affinity hemisphere (CCT3/6/7/8) and reports that CCT8 exhibits little movement between open and closed states and did not exchange nucleotide in the studied conditions, leading to the interpretation that CCT8 may contribute more to substrate binding and/or TRiC assembly than to ATP-driven closure mechanics. (Kelly, 2020, structural characterization) (kelly2020structuralandfunctionala pages 42-48)

This same work notes that the N-termini of CCT3/6/7/8 (including CCT8) form inter-ring stacking/locking in the closed state, providing a plausible structural rationale for subunit-specific contributions to chamber stability. (kelly2020structuralandfunctionala pages 42-48)

4) Clients/substrates (what proteins depend on CCT8/TRiC)

4.1 Best-supported yeast client classes

Direct yeast genetics links CCT8/TRiC to actin folding and microtubule assembly (which depends on tubulin biogenesis), identifying cytoskeletal proteins as the central functional axis for this gene. (Esser et al., 1999; Stoldt et al., 1996) (esser1999disruptionofsix pages 8-10, stoldt1996reviewthecct pages 1-2)

A yeast-focused experimental paper on Cct subunits reiterates that actin and tubulin constitute the bulk of Cct substrates, supporting actin/tubulin as obligate/high-throughput clients. (Kabir et al., 2005, Yeast, Feb 2005; https://doi.org/10.1002/yea.1210) (kabir2005physiologicaleffectsof pages 1-2)

4.2 Broader client spectrum and pathways

CCT/TRiC also interacts with broader client classes (e.g., nascent proteins including WD40 propeller proteins) and assists assembly of multiprotein complexes; these statements are supported by integrative review evidence (not limited to yeast) and are generally considered conserved. (Wilkinson et al., 2022) (wilkinson2022themalariaparasite pages 1-2)

Consistent with this, a dedicated review on CCT substrate specificity emphasizes that CCT has a non-random substrate set and describes yeast quantitative context and interactome breadth, including links to regulators and pathways beyond the cytoskeleton (e.g., complex assembly and regulatory networks). (Willison, 2018) (willison2018thesubstratespecificity pages 2-3, willison2018thesubstratespecificity pages 7-8)

Evidence gap (important for annotation): In the retrieved corpus, there is limited Cct8-only (subunit-resolved) yeast client mapping; most yeast evidence is for the complex-level role. Subunit-specific binding sites are better resolved in recent structural studies (below) but are largely from mammalian TRiC. (liu2023pathwayandmechanism pages 3-4, junsun2024astructuralvista pages 1-2)

5) Recent developments (prioritizing 2023–2024)

5.1 2023: TRiC-mediated tubulin folding pathway mapped with cryo-EM and XL-MS

A 2023 cryo-EM plus crosslinking-MS study resolved multiple TRiC conformational states across its ATPase cycle and captured tubulin in distinct folding stages, mapping a subunit-hemisphere preference for tubulin in the closed chamber. Tubulin in the closed state localized predominantly to the CCT6 hemisphere (including CCT1/3/6/8) with extensive contacts; this explicitly places CCT8 among the principal tubulin-contacting subunits in the productive folding state. (Liu et al., 2023, Communications Biology, May 2023; https://doi.org/10.1038/s42003-023-04915-x) (liu2023pathwayandmechanism pages 3-4)

Visual evidence from this study shows the TRiC subunit arrangement and subunit-specific interaction interfaces between tubulin and CCT3/CCT6/CCT8. (liu2023pathwayandmechanism media d6fba22a, liu2023pathwayandmechanism media ed8bbc3a)

5.2 2024: TRiC cooperation with co-chaperones (PhLP2A/prefoldin) and actin folding

A 2024 Nature Communications cryo-EM/biochemistry study characterized the ATP-driven cycle involving TRiC with prefoldin (PFD) and PhLP2A. In substrate-containing complexes, actin and PhLP2A segregate into opposing chambers and both engage positively charged inner-surface residues contributed by CCT1/3/6/8, again identifying CCT8 as part of the inner-surface contact set relevant to folding/holding in the closed chamber. (Park et al., 2024, Nature Communications, Feb 2024; https://doi.org/10.1038/s41467-024-45242-x) (junsun2024astructuralvista pages 1-2)

5.3 2024: Expanded functional/clinical relevance (“TRiCopathies”) and yeast as a model system for variant interpretation

A 2024 Science study defined a spectrum of neurodevelopmental disorders (“TRiCopathies”) caused by pathogenic variants in TRiC/CCT subunits, reporting that variants in seven of the eight subunits can impair function or assembly. Importantly for real-world implementation, the authors used yeast plasmid-shuffling assays (among other models) to test variant function and identify loss-of-function or dominant-negative behaviors, illustrating a concrete pipeline where yeast TRiC biology informs human variant interpretation. (Kraft et al., 2024, Science, Nov 2024; https://doi.org/10.1126/science.adp8721) (kraft2024brainmalformationsand pages 3-6, kraft2024brainmalformationsand pages 8-10)

6) Quantitative statistics and data relevant to CCT8 function in yeast

6.1 Cct8 abundance (copies per cell)

A quantitative SRM-MS (QconCAT) study of the yeast chaperone network estimated Cct8 at ~6,000 ± 100 copies per cell (with other CCT subunits in comparable low-thousands ranges). (Brownridge et al., 2013, Proteomics, Mar 2013; https://doi.org/10.1002/pmic.201200412) (brownridge2013quantitativeanalysisof pages 5-6)

6.2 System-level throughput: how much protein folding depends on chaperones

Using interaction networks and protein abundance/turnover assumptions, the same study estimated that only ~36% of proteins are annotated as chaperone targets, yet these account for ~62% of total protein synthesis flux (i.e., most newly synthesized protein molecules in the cell). They further estimated that the PFD/CCT route accounts for ~6.5% of total protein flux, with CCT alone <4%. (Brownridge et al., 2013) (brownridge2013quantitativeanalysisof pages 11-12)

6.3 mRNA-level estimate for CCT8

A dedicated substrate-specificity review estimated CCT8 mRNA at ~1.7 copies/cell (scaled from transcriptome estimates), providing an independent quantitative context for expression level. (Willison, 2018) (willison2018thesubstratespecificity pages 7-8)

6.4 CCT occupancy by key clients

Willison (2018) reports that ~50–60% of the cellular CCT pool is estimated to be occupied by folding of actin and tubulin, highlighting why cytoskeletal biogenesis is the most prominent functional axis for CCT8/TRiC in vivo. (Willison, 2018) (willison2018thesubstratespecificity pages 6-7)

7) Current applications and real-world implementations

7.1 Yeast CCT8/TRiC as a platform for interpreting conserved chaperonin dysfunction

The 2024 Science TRiCopathy study demonstrates a concrete implementation where yeast genetics (plasmid shuffling) is used to evaluate the functional impact of human TRiC subunit variants, supporting yeast as a practical translational model for conserved chaperonin systems. (Kraft et al., 2024) (kraft2024brainmalformationsand pages 3-6, kraft2024brainmalformationsand pages 8-10)

7.2 Therapeutic targeting concepts (complex-level; not yeast-specific)

A 2024 review emphasizes CCT/TRiC roles in translation elongation and links the complex to human disease contexts including cancer and viral infection, explicitly framing CCT as a “valuable potential therapeutic target.” (Que et al., 2024; https://doi.org/10.1016/j.heliyon.2024.e29029) (que2024theroleof pages 1-2)

Mechanistic structures from 2023–2024 that localize clients to specific TRiC hemispheres and identify CCT8-including contact sets (tubulin; actin/PhLP2A) provide the type of structural basis generally required for rational design of inhibitors/modulators that target client–chaperonin interfaces, even though the cited studies are not yeast therapeutic studies per se. (Liu et al., 2023; Park et al., 2024) (liu2023pathwayandmechanism pages 3-4, junsun2024astructuralvista pages 1-2)

8) Expert interpretation and analysis (authoritative synthesis)

1. Primary function is complex-integrated folding/assembly, not a standalone activity. The strongest yeast-specific statements tie CCT8 to TRiC and cytoskeletal biogenesis (actin folding and microtubule assembly), and the lethal null phenotype indicates that Cct8p is not redundant with other subunits. (esser1999disruptionofsix pages 8-10)

2. Subunit specialization likely matters mechanistically even if all subunits are essential. Yeast structural/kinetic analysis suggests CCT8 is a low-ATP-affinity subunit with limited nucleotide exchange, plausibly specializing more in substrate binding/assembly and inter-ring locking than in driving closure. This supports a modern view of TRiC as an asymmetric machine with subunit-specific roles. (kelly2020structuralandfunctionala pages 42-48)

3. Recent cryo-EM resolves direct involvement of CCT8 in obligate-client interfaces. High-resolution tubulin-TRiC and actin/PhLP2A-TRiC studies explicitly include CCT8 in the major client-contact sets, strengthening mechanistic plausibility for CCT8’s role in cytoskeletal proteostasis and motivating subunit-informed hypotheses in yeast. (liu2023pathwayandmechanism pages 3-4, junsun2024astructuralvista pages 1-2, liu2023pathwayandmechanism media ed8bbc3a)

4. Quantitative proteomics puts Cct8p in the “core chaperone economy” of the cell. Thousands of copies per cell and significant (though not dominant) flux allocation to the PFD/CCT pathway align with an essential but specialized folding role, consistent with the known focus on high-value clients such as actin/tubulin and certain β-propeller proteins. (brownridge2013quantitativeanalysisof pages 5-6, brownridge2013quantitativeanalysisof pages 11-12, willison2018thesubstratespecificity pages 6-7)

9) Practical functional-annotation statement for yeast CCT8 (recommended)

Gene: CCT8 (YJL008C)

Protein: T-complex protein 1 subunit theta (Cct8p)

Molecular function: Essential subunit of the cytosolic TRiC/CCT ATP-dependent chaperonin; contributes to substrate binding and the conformational cycle that encapsulates non-native clients to promote folding/assembly. (esser1999disruptionofsix pages 8-10, kelly2020structuralandfunctionala pages 42-48)

Biological processes: Cytoskeletal protein biogenesis—actin folding and microtubule assembly; broader cytosolic proteostasis and folding of a defined subset of cytosolic proteins. (esser1999disruptionofsix pages 8-10, kabir2005physiologicaleffectsof pages 1-2, willison2018thesubstratespecificity pages 2-3)

Cellular component: Cytosol/cytoplasm; TRiC/CCT chaperonin complex. (esser1999disruptionofsix pages 8-10, wilkinson2022themalariaparasite pages 1-2)

Essentiality: Essential; null spores arrest after a few divisions and are inviable in tetrad analysis. (esser1999disruptionofsix pages 1-3, esser1999disruptionofsix pages 8-10)

Evidence map table

The following table provides a compact map from claims to evidence.

Table: This table summarizes the most relevant functional-annotation facts for Saccharomyces cerevisiae CCT8/YJL008C, including identity, essentiality, molecular role, localization, substrates, quantitative measurements, and recent mechanistic advances. It is useful as a compact evidence map for building the full research report.

Visual evidence (figure citations)

The 2023 TRiC-tubulin cryo-EM study provides figures showing (i) subunit arrangement and (ii) CCT8-including interfaces with tubulin. (liu2023pathwayandmechanism media d6fba22a, liu2023pathwayandmechanism media ed8bbc3a)

Limitations and open questions (yeast CCT8-specific)

• Subunit-resolved yeast client list remains limited in the retrieved evidence: most yeast data are genetic/complex-level, while the most detailed subunit-contact maps for CCT8 come from mammalian cryo-EM. Translating these to yeast is mechanistically plausible but should be validated by yeast subunit-resolved crosslinking, mutational scanning of Cct8p substrate-binding surfaces, or client co-IP under defined folding states. (liu2023pathwayandmechanism pages 3-4, junsun2024astructuralvista pages 1-2)

• The apparent tension between statements that “all eight CCT genes are essential” and findings that certain low-ATP-affinity subunits tolerate P-loop mutations in some assays likely reflects that essentiality arises from complex integrity and coordinated cycling, not solely from ATP hydrolysis at every subunit. (willison2018thesubstratespecificity pages 2-3, kelly2020structuralandfunctionala pages 42-48)

References

1. (esser1999disruptionofsix pages 1-3): Karlheinz Esser, Bettina Scholle, and Georg Michaelis. Disruption of six open reading frames on chromosome x of saccharomyces cerevisiae reveals a cluster of four essential genes. Yeast, 15:921-933, Jul 1999. URL: https://doi.org/10.1002/(sici)1097-0061(199907)15:10b<921::aid-yea389>3.0.co;2-6, doi:10.1002/(sici)1097-0061(199907)15:10b<921::aid-yea389>3.0.co;2-6. This article has 8 citations and is from a peer-reviewed journal.

2. (esser1999disruptionofsix pages 8-10): Karlheinz Esser, Bettina Scholle, and Georg Michaelis. Disruption of six open reading frames on chromosome x of saccharomyces cerevisiae reveals a cluster of four essential genes. Yeast, 15:921-933, Jul 1999. URL: https://doi.org/10.1002/(sici)1097-0061(199907)15:10b<921::aid-yea389>3.0.co;2-6, doi:10.1002/(sici)1097-0061(199907)15:10b<921::aid-yea389>3.0.co;2-6. This article has 8 citations and is from a peer-reviewed journal.

3. (brownridge2013quantitativeanalysisof pages 5-6): Philip Brownridge, Craig Lawless, Aishwarya B. Payapilly, Karin Lanthaler, Stephen W. Holman, Victoria M. Harman, Christopher M. Grant, Robert J. Beynon, and Simon J. Hubbard. Quantitative analysis of chaperone network throughput in budding yeast. Proteomics, 13:1276-1291, Mar 2013. URL: https://doi.org/10.1002/pmic.201200412, doi:10.1002/pmic.201200412. This article has 43 citations and is from a peer-reviewed journal.

4. (brownridge2013quantitativeanalysisof pages 11-12): Philip Brownridge, Craig Lawless, Aishwarya B. Payapilly, Karin Lanthaler, Stephen W. Holman, Victoria M. Harman, Christopher M. Grant, Robert J. Beynon, and Simon J. Hubbard. Quantitative analysis of chaperone network throughput in budding yeast. Proteomics, 13:1276-1291, Mar 2013. URL: https://doi.org/10.1002/pmic.201200412, doi:10.1002/pmic.201200412. This article has 43 citations and is from a peer-reviewed journal.

5. (liu2023pathwayandmechanism pages 3-4): Caixuan Liu, Mingliang Jin, Shutian Wang, Wenyu Han, Qiaoyu Zhao, Yifan Wang, Cong Xu, Lei Diao, Yue Yin, Chao Peng, Lan Bao, Yanxing Wang, and Yao Cong. Pathway and mechanism of tubulin folding mediated by tric/cct along its atpase cycle revealed using cryo-em. Communications Biology, May 2023. URL: https://doi.org/10.1038/s42003-023-04915-x, doi:10.1038/s42003-023-04915-x. This article has 28 citations and is from a peer-reviewed journal.

6. (junsun2024astructuralvista pages 1-2): Junsun Park, Hyunmin Kim, Daniel Gestaut, Seyeon Lim, Kwadwo A. Opoku-Nsiah, Alexander Leitner, Judith Frydman, and Soung-Hun Roh. A structural vista of phosducin-like phlp2a-chaperonin tric cooperation during the atp-driven folding cycle. Nature Communications, Feb 2024. URL: https://doi.org/10.1038/s41467-024-45242-x, doi:10.1038/s41467-024-45242-x. This article has 16 citations and is from a highest quality peer-reviewed journal.

7. (stoldt1996reviewthecct pages 1-2): Volker Stoldt, Felicitas Rademacher, Verena Kehren, Joachim F. Ernst, David A. Pearce, and Fred Sherman. Review: the cct eukaryotic chaperonin subunits of saccharomyces cerevisiae and other yeasts. Yeast, 12:523-529, May 1996. URL: https://doi.org/10.1002/(sici)1097-0061(199605)12:6<523::aid-yea962>3.0.co;2-c, doi:10.1002/(sici)1097-0061(199605)12:6<523::aid-yea962>3.0.co;2-c. This article has 153 citations and is from a peer-reviewed journal.

8. (wilkinson2022themalariaparasite pages 1-2): Mark D. Wilkinson, Josie L. Ferreira, Morgan Beeby, Jake Baum, and Keith R. Willison. The malaria parasite chaperonin containing tcp-1 (cct) complex: data integration with other cct proteomes. Frontiers in Molecular Biosciences, Dec 2022. URL: https://doi.org/10.3389/fmolb.2022.1057232, doi:10.3389/fmolb.2022.1057232. This article has 1 citations.

9. (que2024theroleof pages 2-4): 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.

10. (kelly2020structuralandfunctionala pages 42-48): J Kelly. Structural and functional characterisation of the group ii chaperonin cct/tric. Unknown journal, 2020.

11. (willison2018thesubstratespecificity pages 2-3): Keith R. Willison. The substrate specificity of eukaryotic cytosolic chaperonin cct. Philosophical Transactions of the Royal Society B: Biological Sciences, 373:20170192, Jun 2018. URL: https://doi.org/10.1098/rstb.2017.0192, doi:10.1098/rstb.2017.0192. This article has 75 citations and is from a domain leading peer-reviewed journal.

12. (kabir2005physiologicaleffectsof pages 1-2): M. Anaul Kabir, Joanna Kaminska, George B. Segel, Gabor Bethlendy, Paul Lin, Flavio Della Seta, Casey Blegen, Kristine M. Swiderek, Teresa ?o??dek, Kim T. Arndt, and Fred Sherman. Physiological effects of unassembled chaperonin cct subunits in the yeast saccharomyces cerevisiae. Yeast, 22:219-239, Feb 2005. URL: https://doi.org/10.1002/yea.1210, doi:10.1002/yea.1210. This article has 60 citations and is from a peer-reviewed journal.

13. (willison2018thesubstratespecificity pages 7-8): Keith R. Willison. The substrate specificity of eukaryotic cytosolic chaperonin cct. Philosophical Transactions of the Royal Society B: Biological Sciences, 373:20170192, Jun 2018. URL: https://doi.org/10.1098/rstb.2017.0192, doi:10.1098/rstb.2017.0192. This article has 75 citations and is from a domain leading peer-reviewed journal.

14. (liu2023pathwayandmechanism media d6fba22a): Caixuan Liu, Mingliang Jin, Shutian Wang, Wenyu Han, Qiaoyu Zhao, Yifan Wang, Cong Xu, Lei Diao, Yue Yin, Chao Peng, Lan Bao, Yanxing Wang, and Yao Cong. Pathway and mechanism of tubulin folding mediated by tric/cct along its atpase cycle revealed using cryo-em. Communications Biology, May 2023. URL: https://doi.org/10.1038/s42003-023-04915-x, doi:10.1038/s42003-023-04915-x. This article has 28 citations and is from a peer-reviewed journal.

15. (liu2023pathwayandmechanism media ed8bbc3a): Caixuan Liu, Mingliang Jin, Shutian Wang, Wenyu Han, Qiaoyu Zhao, Yifan Wang, Cong Xu, Lei Diao, Yue Yin, Chao Peng, Lan Bao, Yanxing Wang, and Yao Cong. Pathway and mechanism of tubulin folding mediated by tric/cct along its atpase cycle revealed using cryo-em. Communications Biology, May 2023. URL: https://doi.org/10.1038/s42003-023-04915-x, doi:10.1038/s42003-023-04915-x. This article has 28 citations and is from a peer-reviewed journal.

16. (kraft2024brainmalformationsand pages 3-6): Florian Kraft, Piere Rodriguez-Aliaga, Weimin Yuan, Lena Franken, Kamil Zajt, Dimah Hasan, Ting-Ting Lee, Elisabetta Flex, Andreas Hentschel, A. Micheil Innes, Bixia Zheng, Dong Sun Julia Suh, Cordula Knopp, Eva Lausberg, Jeremias Krause, Xiaomeng Zhang, Pamela Trapane, Riley Carroll, Martin McClatchey, Andrew E. Fry, Lisa Wang, Sebastian Giesselmann, Hieu Hoang, Dustin Baldridge, Gary A. Silverman, Francesca Clementina Radio, Enrico Bertini, Andrea Ciolfi, Katherine A Blood, Jean-Madeleine de Sainte Agathe, Perrine Charles, Gaber Bergant, Goran Čuturilo, Borut Peterlin, Karin Diderich, Haley Streff, Laurie Robak, Renske Oegema, Ellen van Binsbergen, John Herriges, Carol J. Saunders, Andrea Maier, Stefan Wolking, Yvonne Weber, Hanns Lochmüller, Stefanie Meyer, Alberto Aleman, Kiran Polavarapu, Gael Nicolas, Alice Goldenberg, Lucie Guyant, Kathleen Pope, Katherine N. Hehmeyer, Kristin G. Monaghan, Annegret Quade, Thomas Smol, Roseline Caumes, Sarah Duerinckx, Chantal Depondt, Wim Van Paesschen, Claudine Rieubland, Claudia Poloni, Michel Guipponi, Severine Arcioni, Marije Meuwissen, Anna C. Jansen, Jessica Rosenblum, Tobias B. Haack, Miriam Bertrand, Lea Gerstner, Janine Magg, Olaf Riess, Jörg B. Schulz, Norbert Wagner, Martin Wiesmann, Joachim Weis, Thomas Eggermann, Matthias Begemann, Andreas Roos, Martin Häusler, Tim Schedl, Marco Tartaglia, Juliane Bremer, Stephen C. Pak, Judith Frydman, Miriam Elbracht, and Ingo Kurth. Brain malformations and seizures by impaired chaperonin function of tric. Science, 386 6721:516-525, Nov 2024. URL: https://doi.org/10.1126/science.adp8721, doi:10.1126/science.adp8721. This article has 21 citations and is from a highest quality peer-reviewed journal.

17. (kraft2024brainmalformationsand pages 8-10): Florian Kraft, Piere Rodriguez-Aliaga, Weimin Yuan, Lena Franken, Kamil Zajt, Dimah Hasan, Ting-Ting Lee, Elisabetta Flex, Andreas Hentschel, A. Micheil Innes, Bixia Zheng, Dong Sun Julia Suh, Cordula Knopp, Eva Lausberg, Jeremias Krause, Xiaomeng Zhang, Pamela Trapane, Riley Carroll, Martin McClatchey, Andrew E. Fry, Lisa Wang, Sebastian Giesselmann, Hieu Hoang, Dustin Baldridge, Gary A. Silverman, Francesca Clementina Radio, Enrico Bertini, Andrea Ciolfi, Katherine A Blood, Jean-Madeleine de Sainte Agathe, Perrine Charles, Gaber Bergant, Goran Čuturilo, Borut Peterlin, Karin Diderich, Haley Streff, Laurie Robak, Renske Oegema, Ellen van Binsbergen, John Herriges, Carol J. Saunders, Andrea Maier, Stefan Wolking, Yvonne Weber, Hanns Lochmüller, Stefanie Meyer, Alberto Aleman, Kiran Polavarapu, Gael Nicolas, Alice Goldenberg, Lucie Guyant, Kathleen Pope, Katherine N. Hehmeyer, Kristin G. Monaghan, Annegret Quade, Thomas Smol, Roseline Caumes, Sarah Duerinckx, Chantal Depondt, Wim Van Paesschen, Claudine Rieubland, Claudia Poloni, Michel Guipponi, Severine Arcioni, Marije Meuwissen, Anna C. Jansen, Jessica Rosenblum, Tobias B. Haack, Miriam Bertrand, Lea Gerstner, Janine Magg, Olaf Riess, Jörg B. Schulz, Norbert Wagner, Martin Wiesmann, Joachim Weis, Thomas Eggermann, Matthias Begemann, Andreas Roos, Martin Häusler, Tim Schedl, Marco Tartaglia, Juliane Bremer, Stephen C. Pak, Judith Frydman, Miriam Elbracht, and Ingo Kurth. Brain malformations and seizures by impaired chaperonin function of tric. Science, 386 6721:516-525, Nov 2024. URL: https://doi.org/10.1126/science.adp8721, doi:10.1126/science.adp8721. This article has 21 citations and is from a highest quality peer-reviewed journal.

18. (willison2018thesubstratespecificity pages 6-7): Keith R. Willison. The substrate specificity of eukaryotic cytosolic chaperonin cct. Philosophical Transactions of the Royal Society B: Biological Sciences, 373:20170192, Jun 2018. URL: https://doi.org/10.1098/rstb.2017.0192, doi:10.1098/rstb.2017.0192. This article has 75 citations and is from a domain leading peer-reviewed journal.

19. (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.

20. (brownridge2013quantitativeanalysisof pages 8-9): Philip Brownridge, Craig Lawless, Aishwarya B. Payapilly, Karin Lanthaler, Stephen W. Holman, Victoria M. Harman, Christopher M. Grant, Robert J. Beynon, and Simon J. Hubbard. Quantitative analysis of chaperone network throughput in budding yeast. Proteomics, 13:1276-1291, Mar 2013. URL: https://doi.org/10.1002/pmic.201200412, doi:10.1002/pmic.201200412. This article has 43 citations and is from a peer-reviewed journal.

21. (brownridge2013quantitativeanalysisof pages 6-8): Philip Brownridge, Craig Lawless, Aishwarya B. Payapilly, Karin Lanthaler, Stephen W. Holman, Victoria M. Harman, Christopher M. Grant, Robert J. Beynon, and Simon J. Hubbard. Quantitative analysis of chaperone network throughput in budding yeast. Proteomics, 13:1276-1291, Mar 2013. URL: https://doi.org/10.1002/pmic.201200412, doi:10.1002/pmic.201200412. This article has 43 citations and is from a peer-reviewed journal.

22. (kelly2020structuralandfunctional pages 42-48): J Kelly. Structural and functional characterisation of the group ii chaperonin cct/tric. Unknown journal, 2020.

23. (kabir2005physiologicaleffectsof pages 2-4): M. Anaul Kabir, Joanna Kaminska, George B. Segel, Gabor Bethlendy, Paul Lin, Flavio Della Seta, Casey Blegen, Kristine M. Swiderek, Teresa ?o??dek, Kim T. Arndt, and Fred Sherman. Physiological effects of unassembled chaperonin cct subunits in the yeast saccharomyces cerevisiae. Yeast, 22:219-239, Feb 2005. URL: https://doi.org/10.1002/yea.1210, doi:10.1002/yea.1210. This article has 60 citations and is from a peer-reviewed journal.

24. (stoldt1996reviewthecct pages 2-4): Volker Stoldt, Felicitas Rademacher, Verena Kehren, Joachim F. Ernst, David A. Pearce, and Fred Sherman. Review: the cct eukaryotic chaperonin subunits of saccharomyces cerevisiae and other yeasts. Yeast, 12:523-529, May 1996. URL: https://doi.org/10.1002/(sici)1097-0061(199605)12:6<523::aid-yea962>3.0.co;2-c, doi:10.1002/(sici)1097-0061(199605)12:6<523::aid-yea962>3.0.co;2-c. This article has 153 citations and is from a peer-reviewed journal.

25. (brownridge2013quantitativeanalysisof pages 1-2): Philip Brownridge, Craig Lawless, Aishwarya B. Payapilly, Karin Lanthaler, Stephen W. Holman, Victoria M. Harman, Christopher M. Grant, Robert J. Beynon, and Simon J. Hubbard. Quantitative analysis of chaperone network throughput in budding yeast. Proteomics, 13:1276-1291, Mar 2013. URL: https://doi.org/10.1002/pmic.201200412, doi:10.1002/pmic.201200412. This article has 43 citations and is from a peer-reviewed journal.

Citations

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