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Que Y, Qiu Y, Ding Z, Zhang S, Wei R, Xia J, Lin Y. The role of molecular chaperone CCT/TRiC in translation elongation: A literature review. Heliyon 2024; 10:e29029. [PMID: 38596045 PMCID: PMC11002246 DOI: 10.1016/j.heliyon.2024.e29029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Revised: 03/27/2024] [Accepted: 03/28/2024] [Indexed: 04/11/2024] Open
Abstract
Protein synthesis from mRNA is an energy-intensive and strictly controlled biological process. Translation elongation is a well-coordinated and multifactorial step in translation that ensures the accurate and efficient addition of amino acids to a growing nascent-peptide chain encoded in the sequence of messenger RNA (mRNA). Which undergoes dynamic regulation due to cellular state and environmental determinants. An expanding body of research points to translational elongation as a crucial process that controls the translation of an mRNA through multiple feedback mechanisms. Molecular chaperones are key players in protein homeostasis to keep the balance between protein synthesis, folding, assembly, and degradation. Chaperonin-containing tailless complex polypeptide 1 (CCT) or tailless complex polypeptide 1 ring complex (TRiC) is an essential eukaryotic molecular chaperone that plays an essential role in assisting cellular protein folding and suppressing protein aggregation. In this review, we give an overview of the factors that influence translation elongation, focusing on different functions of molecular chaperones in translation elongation, including how they affect translation rates and post-translational modifications. We also provide an understanding of the mechanisms by which the molecular chaperone CCT plays multiple roles in the elongation phase of eukaryotic protein synthesis.
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Affiliation(s)
- Yueyue Que
- School of Pharmacy, Hangzhou Normal University, Hangzhou, Zhejiang 311121, China
- Key Laboratory of Elemene Class Anti-Cancer Chinese Medicines, Engineering Laboratory of Development and Application of Traditional Chinese Medicines, Collaborative Innovation Center of Traditional Chinese Medicines of Zhejiang Province, Hangzhou Normal University, Hangzhou, Zhejiang 311121, China
| | - Yudan Qiu
- School of Pharmacy, Hangzhou Normal University, Hangzhou, Zhejiang 311121, China
- Key Laboratory of Elemene Class Anti-Cancer Chinese Medicines, Engineering Laboratory of Development and Application of Traditional Chinese Medicines, Collaborative Innovation Center of Traditional Chinese Medicines of Zhejiang Province, Hangzhou Normal University, Hangzhou, Zhejiang 311121, China
| | - Zheyu Ding
- School of Pharmacy, Hangzhou Normal University, Hangzhou, Zhejiang 311121, China
- Key Laboratory of Elemene Class Anti-Cancer Chinese Medicines, Engineering Laboratory of Development and Application of Traditional Chinese Medicines, Collaborative Innovation Center of Traditional Chinese Medicines of Zhejiang Province, Hangzhou Normal University, Hangzhou, Zhejiang 311121, China
| | - Shanshan Zhang
- School of Pharmacy, Hangzhou Normal University, Hangzhou, Zhejiang 311121, China
- Key Laboratory of Elemene Class Anti-Cancer Chinese Medicines, Engineering Laboratory of Development and Application of Traditional Chinese Medicines, Collaborative Innovation Center of Traditional Chinese Medicines of Zhejiang Province, Hangzhou Normal University, Hangzhou, Zhejiang 311121, China
| | - Rong Wei
- School of Pharmacy, Hangzhou Normal University, Hangzhou, Zhejiang 311121, China
- Key Laboratory of Elemene Class Anti-Cancer Chinese Medicines, Engineering Laboratory of Development and Application of Traditional Chinese Medicines, Collaborative Innovation Center of Traditional Chinese Medicines of Zhejiang Province, Hangzhou Normal University, Hangzhou, Zhejiang 311121, China
| | - Jianing Xia
- School of Pharmacy, Hangzhou Normal University, Hangzhou, Zhejiang 311121, China
- Key Laboratory of Elemene Class Anti-Cancer Chinese Medicines, Engineering Laboratory of Development and Application of Traditional Chinese Medicines, Collaborative Innovation Center of Traditional Chinese Medicines of Zhejiang Province, Hangzhou Normal University, Hangzhou, Zhejiang 311121, China
| | - Yingying Lin
- School of Pharmacy, Hangzhou Normal University, Hangzhou, Zhejiang 311121, China
- Key Laboratory of Elemene Class Anti-Cancer Chinese Medicines, Engineering Laboratory of Development and Application of Traditional Chinese Medicines, Collaborative Innovation Center of Traditional Chinese Medicines of Zhejiang Province, Hangzhou Normal University, Hangzhou, Zhejiang 311121, China
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Smith TM, Willardson BM. Mechanistic insights into protein folding by the eukaryotic chaperonin complex CCT. Biochem Soc Trans 2022; 50:1403-1414. [PMID: 36196890 PMCID: PMC9704529 DOI: 10.1042/bst20220591] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 09/08/2022] [Accepted: 09/09/2022] [Indexed: 11/17/2022]
Abstract
The cytosolic chaperonin CCT is indispensable to eukaryotic life, folding the cytoskeletal proteins actin and tubulin along with an estimated 10% of the remaining proteome. However, it also participates in human diseases such as cancer and viral infections, rendering it valuable as a potential therapeutic target. CCT consists of two stacked rings, each comprised of eight homologous but distinct subunits, that assists the folding of a remarkable substrate clientele that exhibits both broad diversity and specificity. Much of the work in recent years has been aimed at understanding the mechanisms of CCT substrate recognition and folding. These studies have revealed new binding sites and mechanisms by which CCT uses its distinctive subunit arrangement to fold structurally unrelated substrates. Here, we review recent structural insights into CCT-substrate interactions and place them into the broader context of CCT function and its implications for human health.
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Affiliation(s)
- Theresa M. Smith
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT 84602, U.S.A
| | - Barry M. Willardson
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT 84602, U.S.A
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3
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Bi Y, Jing Y, Guo L. Construction and validation of a prognostic marker and risk model for HCC ultrasound therapy combined with WGCNA identification. Front Genet 2022; 13:1017551. [PMID: 36263426 PMCID: PMC9573990 DOI: 10.3389/fgene.2022.1017551] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Accepted: 09/12/2022] [Indexed: 11/23/2022] Open
Abstract
Background: Hepatocellular carcinoma (HCC) is a malignant tumor with a highly aggressive and metastatic nature. Ultrasound remains a routine monitoring tool for screening, treatment and post-treatment recheck of HCC. Therefore, it is of great significance to explore the role of ultrasound therapy and related genes in prognosis prediction and clinical diagnosis and treatment of HCC. Methods: Gene co-expression networks were developed utilizing the R package WGCNA as per the expression profiles and clinical features of TCGA HCC samples, key modules were identified by the correlation coefficients between clinical features and modules, and hub genes of modules were determined as per the GS and MM values. Ultrasound treatment differential expression genes were identified using R package limma, and univariate Cox analysis was conducted on the intersection genes of ultrasound differential expression genes and hub genes of key HCC modules to screen the signatures linked with HCC prognosis and construct a risk model. The median risk score was used as the threshold point to classify tumor samples into high- and low-risk groups, and the R package IOBR was used to assess the proportion of immune cells in high- and low-risk groups, R package maftools to assess the genomic mutation differences in high- and low-risk groups, R package GSVA’s ssgsea algorithm to assess the HALLMARK pathway enrichment analysis, and R package pRRophetic to analyze drug sensitivity in patients with HCC. Results: WGCNA analysis based on the expression profiles and clinical data of the TCGA LIHC cohort identified three key modules with two major clinical features associated with HCC. The intersection of ultrasound-related differential genes and module hub genes was selected for univariate Cox analysis to identify prognostic factors significantly associated with HCC, and a risk score model consisting of six signatures was finally developed to analyze the prognosis of individuals with HCC. The risk model showed strength in the training set, overall set, and external validation set. The percentage of immune cell infiltration, genomic mutations, pathway enrichment scores, and chemotherapy drug resistance were significantly different between high- and low-risk groups according to the risk scores. Expression of model genes correlated with tumor immune microenvironment and clinical tumor characteristics while generally differentially expressed in pan-cancer tumor and healthy samples. In the immunotherapy dataset, patients in the high-risk group had a worse prognosis with immunotherapy, indicating that subjects in the low-risk group are more responsive to immunotherapy. Conclusion: The 6-gene signature constructed by ultrasound treatment of HCC combined with WGCNA analysis can be used for prognosis prediction of HCC patients and may become a marker for immune response.
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Affiliation(s)
- Yunlong Bi
- Department of Orthopedics, First Affiliated Hospital of Jinzhou Medical University, Jinzhou, China
| | - Yu Jing
- Department of Oncology, First Affiliated Hospital of Jinzhou Medical University, Jinzhou, China
| | - Lingling Guo
- Department of Ultrasound, First Affiliated Hospital of Jinzhou Medical University, Jinzhou, China
- *Correspondence: Lingling Guo,
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Horovitz A, Reingewertz TH, Cuéllar J, Valpuesta JM. Chaperonin Mechanisms: Multiple and (Mis)Understood? Annu Rev Biophys 2022; 51:115-133. [DOI: 10.1146/annurev-biophys-082521-113418] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The chaperonins are ubiquitous and essential nanomachines that assist in protein folding in an ATP-driven manner. They consist of two back-to-back stacked oligomeric rings with cavities in which protein (un)folding can take place in a shielding environment. This review focuses on GroEL from Escherichia coli and the eukaryotic chaperonin-containing t-complex polypeptide 1, which differ considerably in their reaction mechanisms despite sharing a similar overall architecture. Although chaperonins feature in many current biochemistry textbooks after being studied intensively for more than three decades, key aspects of their reaction mechanisms remain under debate and are discussed in this review. In particular, it is unclear whether a universal reaction mechanism operates for all substrates and whether it is passive, i.e., aggregation is prevented but the folding pathway is unaltered, or active. It is also unclear how chaperonin clients are distinguished from nonclients and what are the precise roles of the cofactors with which chaperonins interact. Expected final online publication date for the Annual Review of Biophysics, Volume 51 is May 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- Amnon Horovitz
- Department of Chemical and Structural Biology, Weizmann Institute of Science, Rehovot, Israel; Amnon.H
| | - Tali Haviv Reingewertz
- Department of Chemical and Structural Biology, Weizmann Institute of Science, Rehovot, Israel; Amnon.H
| | - Jorge Cuéllar
- Department of Macromolecular Structure, Centro Nacional de Biotecnología (CNB-CSIC), Madrid, Spain
| | - José María Valpuesta
- Department of Macromolecular Structure, Centro Nacional de Biotecnología (CNB-CSIC), Madrid, Spain
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CryoEM reveals the stochastic nature of individual ATP binding events in a group II chaperonin. Nat Commun 2021; 12:4754. [PMID: 34362932 PMCID: PMC8346469 DOI: 10.1038/s41467-021-25099-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Accepted: 07/21/2021] [Indexed: 12/05/2022] Open
Abstract
Chaperonins are homo- or hetero-oligomeric complexes that use ATP binding and hydrolysis to facilitate protein folding. ATP hydrolysis exhibits both positive and negative cooperativity. The mechanism by which chaperonins coordinate ATP utilization in their multiple subunits remains unclear. Here we use cryoEM to study ATP binding in the homo-oligomeric archaeal chaperonin from Methanococcus maripaludis (MmCpn), consisting of two stacked rings composed of eight identical subunits each. Using a series of image classification steps, we obtained different structural snapshots of individual chaperonins undergoing the nucleotide binding process. We identified nucleotide-bound and free states of individual subunits in each chaperonin, allowing us to determine the ATP occupancy state of each MmCpn particle. We observe distinctive tertiary and quaternary structures reflecting variations in nucleotide occupancy and subunit conformations in each chaperonin complex. Detailed analysis of the nucleotide distribution in each MmCpn complex indicates that individual ATP binding events occur in a statistically random manner for MmCpn, both within and across the rings. Our findings illustrate the power of cryoEM to characterize a biochemical property of multi-subunit ligand binding cooperativity at the individual particle level. The mechanism by which chaperonins coordinate ATP utilization in their multiple subunits remains unclear. Here, the authors employ an approach that uses cryo-EM single particle analysis to track the number and distribution of nucleotides bound to each subunit in the homo-oligomeric MmCpn archaeal chaperonin complex and observe that ATP binds in a statistically random manner to MmCpn both within a ring and across the rings, which shows that there is no cooperativity in ATP binding to archaeal group II chaperonins under the conditions used in this study.
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Chaperonin point mutation enhances cadmium endurance in Saccharomyces cerevisiae. Biotechnol Lett 2021; 43:1735-1745. [PMID: 34047865 DOI: 10.1007/s10529-021-03151-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Accepted: 05/25/2021] [Indexed: 11/27/2022]
Abstract
OBJECTIVE To study the effect of the mutation in conserved G412E in Cct7p subunit of CCT complex on its cellular fate. RESULTS TriC/CCT is a dynamic multimeric protein that assists in protein folding in an energy-dependent manner. A point mutation in the ATP binding pocket in the equatorial domain of the Cct7p subunit delays the doubling time. The cell size was twice the wild type, and the formation of protein aggregates suggests disturbed folding of the proteins. Upon growing in stressful conditions of arsenous acid and cadmium chloride, the mutant was lethal in As3+ but grew well in Cd2+ with 10.5 µg cadmium uptake mg-1 compared to the wild type. The increased expression of vacuole transporters YCF1 and BPT1 by ten-fold and two-fold in mutant indicates the metal transportation to the vacuole. CONCLUSION CCT complex was vulnerable to the mutation in G412E in the Cct7p subunit of protein folding molecular machinery. Interestingly, already stressed cells provided robustness against oxidative stress and cadmium sequestration in the vacuole.
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Zhang Y, Krieger J, Mikulska-Ruminska K, Kaynak B, Sorzano COS, Carazo JM, Xing J, Bahar I. State-dependent sequential allostery exhibited by chaperonin TRiC/CCT revealed by network analysis of Cryo-EM maps. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2021; 160:104-120. [PMID: 32866476 PMCID: PMC7914283 DOI: 10.1016/j.pbiomolbio.2020.08.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 06/25/2020] [Accepted: 08/16/2020] [Indexed: 12/17/2022]
Abstract
The eukaryotic chaperonin TRiC/CCT plays a major role in assisting the folding of many proteins through an ATP-driven allosteric cycle. Recent structures elucidated by cryo-electron microscopy provide a broad view of the conformations visited at various stages of the chaperonin cycle, including a sequential activation of its subunits in response to nucleotide binding. But we lack a thorough mechanistic understanding of the structure-based dynamics and communication properties that underlie the TRiC/CCT machinery. In this study, we present a computational methodology based on elastic network models adapted to cryo-EM density maps to gain a deeper understanding of the structure-encoded allosteric dynamics of this hexadecameric machine. We have analysed several structures of the chaperonin resolved in different states toward mapping its conformational landscape. Our study indicates that the overall architecture intrinsically favours cooperative movements that comply with the structural variabilities observed in experiments. Furthermore, the individual subunits CCT1-CCT8 exhibit state-dependent sequential events at different states of the allosteric cycle. For example, in the ATP-bound state, subunits CCT5 and CCT4 selectively initiate the lid closure motions favoured by the overall architecture; whereas in the apo form of the heteromer, the subunit CCT7 exhibits the highest predisposition to structural change. The changes then propagate through parallel fluxes of allosteric signals to neighbours on both rings. The predicted state-dependent mechanisms of sequential activation provide new insights into TRiC/CCT intra- and inter-ring signal transduction events.
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Affiliation(s)
- Yan Zhang
- Department of Computational and Systems Biology, University of Pittsburgh, 800 Murdoch Building, 3420 Forbes Avenue, Pittsburgh, PA, 15261, USA
| | - James Krieger
- Department of Computational and Systems Biology, University of Pittsburgh, 800 Murdoch Building, 3420 Forbes Avenue, Pittsburgh, PA, 15261, USA
| | - Karolina Mikulska-Ruminska
- Department of Computational and Systems Biology, University of Pittsburgh, 800 Murdoch Building, 3420 Forbes Avenue, Pittsburgh, PA, 15261, USA
| | - Burak Kaynak
- Department of Computational and Systems Biology, University of Pittsburgh, 800 Murdoch Building, 3420 Forbes Avenue, Pittsburgh, PA, 15261, USA
| | | | - José-María Carazo
- Centro Nacional de Biotecnología (CSIC), Darwin, 3, 28049, Madrid, Spain
| | - Jianhua Xing
- Department of Computational and Systems Biology, University of Pittsburgh, 800 Murdoch Building, 3420 Forbes Avenue, Pittsburgh, PA, 15261, USA
| | - Ivet Bahar
- Department of Computational and Systems Biology, University of Pittsburgh, 800 Murdoch Building, 3420 Forbes Avenue, Pittsburgh, PA, 15261, USA.
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Rattanapornsompong K, Khattiya J, Phannasil P, Phaonakrop N, Roytrakul S, Jitrapakdee S, Akekawatchai C. Impaired G2/M cell cycle arrest induces apoptosis in pyruvate carboxylase knockdown MDA-MB-231 cells. Biochem Biophys Rep 2021; 25:100903. [PMID: 33490650 PMCID: PMC7806519 DOI: 10.1016/j.bbrep.2020.100903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 12/24/2020] [Accepted: 12/25/2020] [Indexed: 11/02/2022] Open
Abstract
Background Previous studies showed that suppression of pyruvate carboxylase (PC) expression in highly invasive breast cancer cell line, MDA-MB-231 inhibits cell growth as a consequence of the impaired cellular biosynthesis. However, the precise cellular mechanism underlying this growth restriction is unknown. Methods We generated the PC knockdown (PCKD) MDA-MB-231 cells and assessed their phenotypic changes by fluorescence microscopy, proliferation, apoptotic, cell cycle assays and proteomics. Results PC knockdown MDA-MB-231 cells had a low percentage of cell viability in association with accumulation of abnormal cells with large or multi-nuclei. Flow cytometric analysis of annexin V-7-AAD positive cells showed that depletion of PC expression triggers apoptosis with the highest rate at day 4. The increased rate of apoptosis is consistent with increased cleavage of procaspase 3 and poly (ADP-Ribose) polymerase. Cell cycle analysis showed that the apoptotic cell death was associated with G2/M arrest, in parallel with marked reduction of cyclin B levels. Proteomic analysis of PCKD cells identified 9 proteins whose expression changes were correlated with the degree of apoptosis and G2/M cell cycle arrest in the PCKD cells. STITCH analysis indicated 3 of 9 candidate proteins, CCT3, CABIN1 and HECTD3, that form interactions with apoptotic and cell cycle signaling networks linking to PC via MgATP. Conclusions Suppression of PC in MDA-MB-231 cells induces G2/M arrest, leading to apoptosis. Proteomic analysis supports the potential involvement of PC expression in the aberrant cell cycle and apoptosis, and identifies candidate proteins responsible for the PC-mediated cell cycle arrest and apoptosis in breast cancer cells. General significance Our results highlight the possibility of the use of PC as an anti-cancer drug target.
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Affiliation(s)
| | - Janya Khattiya
- Department of Medical Technology, Faculty of Allied Health Sciences, Thammasat University, Pathumthani, Thailand.,Graduate Program in Biomedical Sciences, Faculty of Allied Health Sciences, Thammasat University, Pathumthani, Thailand
| | - Phatchariya Phannasil
- Thalassemia Research Center, Institute of Molecular Biosciences, Mahidol University, Nakhon-Pathom, Thailand
| | - Narumon Phaonakrop
- Functional Ingredients and Food Innovation Research Group, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Pathumthani, Thailand
| | - Sittiruk Roytrakul
- Functional Ingredients and Food Innovation Research Group, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Pathumthani, Thailand
| | - Sarawut Jitrapakdee
- Department of Biochemistry, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Chareeporn Akekawatchai
- Department of Medical Technology, Faculty of Allied Health Sciences, Thammasat University, Pathumthani, Thailand
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Structural basis for active single and double ring complexes in human mitochondrial Hsp60-Hsp10 chaperonin. Nat Commun 2020; 11:1916. [PMID: 32317635 PMCID: PMC7174398 DOI: 10.1038/s41467-020-15698-8] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Accepted: 03/17/2020] [Indexed: 01/21/2023] Open
Abstract
mHsp60-mHsp10 assists the folding of mitochondrial matrix proteins without the negative ATP binding inter-ring cooperativity of GroEL-GroES. Here we report the crystal structure of an ATP (ADP:BeF3-bound) ground-state mimic double-ring mHsp6014-(mHsp107)2 football complex, and the cryo-EM structures of the ADP-bound successor mHsp6014-(mHsp107)2 complex, and a single-ring mHsp607-mHsp107 half-football. The structures explain the nucleotide dependence of mHsp60 ring formation, and reveal an inter-ring nucleotide symmetry consistent with the absence of negative cooperativity. In the ground-state a two-fold symmetric H-bond and a salt bridge stitch the double-rings together, whereas only the H-bond remains as the equatorial gap increases in an ADP football poised to split into half-footballs. Refolding assays demonstrate obligate single- and double-ring mHsp60 variants are active, and complementation analysis in bacteria shows the single-ring variant is as efficient as wild-type mHsp60. Our work provides a structural basis for active single- and double-ring complexes coexisting in the mHsp60-mHsp10 chaperonin reaction cycle.
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Abstract
This chronologue seeks to document the discovery and development of an understanding of oligomeric ring protein assemblies known as chaperonins that assist protein folding in the cell. It provides detail regarding genetic, physiologic, biochemical, and biophysical studies of these ATP-utilizing machines from both in vivo and in vitro observations. The chronologue is organized into various topics of physiology and mechanism, for each of which a chronologic order is generally followed. The text is liberally illustrated to provide firsthand inspection of the key pieces of experimental data that propelled this field. Because of the length and depth of this piece, the use of the outline as a guide for selected reading is encouraged, but it should also be of help in pursuing the text in direct order.
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Zhang Y, Doruker P, Kaynak B, Zhang S, Krieger J, Li H, Bahar I. Intrinsic dynamics is evolutionarily optimized to enable allosteric behavior. Curr Opin Struct Biol 2019; 62:14-21. [PMID: 31785465 DOI: 10.1016/j.sbi.2019.11.002] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Revised: 10/31/2019] [Accepted: 11/04/2019] [Indexed: 12/13/2022]
Abstract
Allosteric behavior is central to the function of many proteins, enabling molecular machinery, metabolism, signaling and regulation. Recent years have shown that the intrinsic dynamics of allosteric proteins defined by their 3-dimensional architecture or by the topology of inter-residue contacts favors cooperative motions that bear close similarity to structural changes they undergo during their allosteric actions. These conformational motions are usually driven by energetically favorable or soft modes at the low frequency end of the mode spectrum, and they are evolutionarily conserved among orthologs. These observations brought into light evolutionary adaptation mechanisms that help maintain, optimize or regulate allosteric behavior as the evolution from bacterial to higher organisms introduces sequential heterogeneities and structural complexities.
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Affiliation(s)
- Yan Zhang
- Department of Computational and Systems Biology, School of Medicine, University of Pittsburgh, 3501 Fifth Ave, Suite 3064 BST3, Pittsburgh, PA 15260, USA
| | - Pemra Doruker
- Department of Computational and Systems Biology, School of Medicine, University of Pittsburgh, 3501 Fifth Ave, Suite 3064 BST3, Pittsburgh, PA 15260, USA
| | - Burak Kaynak
- Department of Computational and Systems Biology, School of Medicine, University of Pittsburgh, 3501 Fifth Ave, Suite 3064 BST3, Pittsburgh, PA 15260, USA
| | - She Zhang
- Department of Computational and Systems Biology, School of Medicine, University of Pittsburgh, 3501 Fifth Ave, Suite 3064 BST3, Pittsburgh, PA 15260, USA
| | - James Krieger
- Department of Computational and Systems Biology, School of Medicine, University of Pittsburgh, 3501 Fifth Ave, Suite 3064 BST3, Pittsburgh, PA 15260, USA
| | - Hongchun Li
- Department of Computational and Systems Biology, School of Medicine, University of Pittsburgh, 3501 Fifth Ave, Suite 3064 BST3, Pittsburgh, PA 15260, USA; Research Center for Computer-Aided Drug Discovery, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Ivet Bahar
- Department of Computational and Systems Biology, School of Medicine, University of Pittsburgh, 3501 Fifth Ave, Suite 3064 BST3, Pittsburgh, PA 15260, USA.
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An ensemble of cryo-EM structures of TRiC reveal its conformational landscape and subunit specificity. Proc Natl Acad Sci U S A 2019; 116:19513-19522. [PMID: 31492816 PMCID: PMC6765261 DOI: 10.1073/pnas.1903976116] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
The ATP-fueled TRiC/CCT acts in the folding of 10% cytosolic proteins. TRiC consists of 8 paralogous subunits, each of which plays special roles in TRiC assembly, allosteric cooperativity, and substrate folding. However, due to lack of a thorough picture of TRiC conformational landscape and atomic-resolution details, the underlying structural mechanisms of TRiC subunit specificity in nucleotide usage and substrate binding, and the allosteric transition during ring closure remain unclear. Here, through cryo-electron microscopy (cryo-EM) analysis, we captured a thorough picture of TRiC conformational landscape from open to closed states and its gradually enhanced allosteric coordination, including the N termini, in unprecedented structural detail. Our study also offers insights into the TRiC subunit specificities in nucleotide usage and ring closure. TRiC/CCT assists the folding of ∼10% of cytosolic proteins through an ATP-driven conformational cycle and is essential in maintaining protein homeostasis. Here, we determined an ensemble of cryo-electron microscopy (cryo-EM) structures of yeast TRiC at various nucleotide concentrations, with 4 open-state maps resolved at near-atomic resolutions, and a closed-state map at atomic resolution, revealing an extra layer of an unforeseen N-terminal allosteric network. We found that, during TRiC ring closure, the CCT7 subunit moves first, responding to nucleotide binding; CCT4 is the last to bind ATP, serving as an ATP sensor; and CCT8 remains ADP-bound and is hardly involved in the ATPase-cycle in our experimental conditions; overall, yeast TRiC consumes nucleotide in a 2-ring positively coordinated manner. Our results depict a thorough picture of the TRiC conformational landscape and its allosteric transitions from the open to closed states in more structural detail and offer insights into TRiC subunit specificity in ATP consumption and ring closure, and potentially in substrate processing.
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Tafoya S, Bustamante C. Molecular switch-like regulation in motor proteins. Philos Trans R Soc Lond B Biol Sci 2019; 373:rstb.2017.0181. [PMID: 29735735 DOI: 10.1098/rstb.2017.0181] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/22/2017] [Indexed: 11/12/2022] Open
Abstract
Motor proteins are powered by nucleotide hydrolysis and exert mechanical work to carry out many fundamental biological tasks. To ensure their correct and efficient performance, the motors' activities are allosterically regulated by additional factors that enhance or suppress their NTPase activity. Here, we review two highly conserved mechanisms of ATP hydrolysis activation and repression operating in motor proteins-the glutamate switch and the arginine finger-and their associated regulatory factors. We examine the implications of these regulatory mechanisms in proteins that are formed by multiple ATPase subunits. We argue that the regulatory mechanisms employed by motor proteins display features similar to those described in small GTPases, which require external regulatory elements, such as dissociation inhibitors, exchange factors and activating proteins, to switch the protein's function 'on' and 'off'. Likewise, similar regulatory roles are taken on by the motor's substrate, additional binding factors, and even adjacent subunits in multimeric complexes. However, in motor proteins, more than one regulatory factor and the two mechanisms described here often underlie the machine's operation. Furthermore, ATPase regulation takes place throughout the motor's cycle, which enables a more complex function than the binary 'active' and 'inactive' states.This article is part of a discussion meeting issue 'Allostery and molecular machines'.
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Affiliation(s)
- Sara Tafoya
- Jason L. Choy Laboratory of Single Molecule Biophysics and Biophysics Graduate Group, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Carlos Bustamante
- Jason L. Choy Laboratory of Single Molecule Biophysics and Biophysics Graduate Group, University of California, Berkeley, Berkeley, CA 94720, USA .,Departments of Molecular and Cell Biology, Physics and Chemistry, University of California, Berkeley, Berkeley, CA 94720, USA.,Howard Hughes Medical Institute, California Institute for Quantitative Biosciences and Kavli Energy Nanoscience Institute, University of California, Berkeley, Berkeley, CA 94720, USA
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Gruber R, Horovitz A. Unpicking allosteric mechanisms of homo-oligomeric proteins by determining their successive ligand binding constants. Philos Trans R Soc Lond B Biol Sci 2019; 373:rstb.2017.0176. [PMID: 29735730 DOI: 10.1098/rstb.2017.0176] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/09/2018] [Indexed: 11/12/2022] Open
Abstract
Advances in native mass spectrometry and single-molecule techniques have made it possible in recent years to determine the values of successive ligand binding constants for large multi-subunit proteins. Given these values, it is possible to distinguish between different allosteric mechanisms and, thus, obtain insights into how various bio-molecular machines work. Here, we describe for ring-shaped homo-oligomers, in particular, how the relationship between the values of successive ligand binding constants is diagnostic for concerted, sequential and probabilistic allosteric mechanisms.This article is part of a discussion meeting issue 'Allostery and molecular machines'.
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Affiliation(s)
- Ranit Gruber
- Department of Structural Biology, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Amnon Horovitz
- Department of Structural Biology, Weizmann Institute of Science, Rehovot 7610001, Israel
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15
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Willison KR. The substrate specificity of eukaryotic cytosolic chaperonin CCT. Philos Trans R Soc Lond B Biol Sci 2019; 373:rstb.2017.0192. [PMID: 29735743 DOI: 10.1098/rstb.2017.0192] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/12/2018] [Indexed: 12/22/2022] Open
Abstract
The cytosolic chaperonin CCT (chaperonin containing TCP-1) is an ATP-dependent double-ring protein machine mediating the folding of members of the eukaryotic cytoskeletal protein families. The actins and tubulins are obligate substrates of CCT because they are completely dependent on CCT activity to reach their native states. Genetic and proteomic analysis of the CCT interactome in the yeast Saccharomyces cerevisiae revealed a CCT network of approximately 300 genes and proteins involved in many fundamental biological processes. We classified network members into sets such as substrates, CCT cofactors and CCT-mediated assembly processes. Many members of the 7-bladed propeller family of proteins are commonly found tightly bound to CCT isolated from human and plant cells and yeasts. The anaphase promoting complex (APC/C) cofactor propellers, Cdh1p and Cdc20p, are also obligate substrates since they both require CCT for folding and functional activation. In vitro translation analysis in prokaryotic and eukaryotic cell extracts of a set of yeast propellers demonstrates their highly differential interactions with CCT and GroEL (another chaperonin). Individual propeller proteins have idiosyncratic interaction modes with CCT because they emerged independently with neo-functions many times throughout eukaryotic evolution. We present a toy model in which cytoskeletal protein biogenesis and folding flux through CCT couples cell growth and size control to time dependent cell cycle mechanisms.This article is part of a discussion meeting issue 'Allostery and molecular machines'.
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Affiliation(s)
- Keith R Willison
- Department of Chemistry, Imperial College London, South Kensington Campus, London SW7 2AZ, UK
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16
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Wodak SJ, Paci E, Dokholyan NV, Berezovsky IN, Horovitz A, Li J, Hilser VJ, Bahar I, Karanicolas J, Stock G, Hamm P, Stote RH, Eberhardt J, Chebaro Y, Dejaegere A, Cecchini M, Changeux JP, Bolhuis PG, Vreede J, Faccioli P, Orioli S, Ravasio R, Yan L, Brito C, Wyart M, Gkeka P, Rivalta I, Palermo G, McCammon JA, Panecka-Hofman J, Wade RC, Di Pizio A, Niv MY, Nussinov R, Tsai CJ, Jang H, Padhorny D, Kozakov D, McLeish T. Allostery in Its Many Disguises: From Theory to Applications. Structure 2019; 27:566-578. [PMID: 30744993 PMCID: PMC6688844 DOI: 10.1016/j.str.2019.01.003] [Citation(s) in RCA: 233] [Impact Index Per Article: 46.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Revised: 11/29/2018] [Accepted: 01/02/2019] [Indexed: 12/19/2022]
Abstract
Allosteric regulation plays an important role in many biological processes, such as signal transduction, transcriptional regulation, and metabolism. Allostery is rooted in the fundamental physical properties of macromolecular systems, but its underlying mechanisms are still poorly understood. A collection of contributions to a recent interdisciplinary CECAM (Center Européen de Calcul Atomique et Moléculaire) workshop is used here to provide an overview of the progress and remaining limitations in the understanding of the mechanistic foundations of allostery gained from computational and experimental analyses of real protein systems and model systems. The main conceptual frameworks instrumental in driving the field are discussed. We illustrate the role of these frameworks in illuminating molecular mechanisms and explaining cellular processes, and describe some of their promising practical applications in engineering molecular sensors and informing drug design efforts.
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Affiliation(s)
| | | | - Nikolay V Dokholyan
- Department of Biochemistry & Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA; Departments of Pharmacology and Biochemistry & Molecular Biology, Penn State Medical Center, Hershey, PA, USA
| | - Igor N Berezovsky
- Bioinformatics Institute (BII), Agency for Science, Technology and Research (A(∗)STAR), and Department of Biological Sciences, National University of Singapore, Singapore, Singapore
| | - Amnon Horovitz
- Department of Structural Biology, Weizmann Institute of Science, Rehovot, Israel
| | - Jing Li
- Departments of Biology and T.C. Jenkins Department of Biophysics, Johns Hopkins University, Baltimore, USA
| | - Vincent J Hilser
- Departments of Biology and T.C. Jenkins Department of Biophysics, Johns Hopkins University, Baltimore, USA
| | - Ivet Bahar
- School of Medicine, University of Pittsburgh, Pittsburgh, USA
| | | | - Gerhard Stock
- Biomolecular Dynamics, Institute of Physics, Albert Ludwigs University, Freiburg, Germany
| | - Peter Hamm
- Department of Chemistry, University of Zurich, Zurich, Switzerland
| | - Roland H Stote
- Department of Integrative Structural Biology, Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Illkirch, France
| | - Jerome Eberhardt
- Department of Integrative Structural Biology, Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Illkirch, France
| | - Yassmine Chebaro
- Department of Integrative Structural Biology, Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Illkirch, France
| | - Annick Dejaegere
- Department of Integrative Structural Biology, Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Illkirch, France
| | - Marco Cecchini
- Institut de Chimie de Strasbourg, UMR7177 CNRS & Université de Strasbourg, Strasbourg, France
| | | | - Peter G Bolhuis
- van 't Hoff Institute for Molecular Sciences (HIMS), University of Amsterdam, Amsterdam, Netherlands
| | - Jocelyne Vreede
- van 't Hoff Institute for Molecular Sciences (HIMS), University of Amsterdam, Amsterdam, Netherlands
| | - Pietro Faccioli
- Physics Department, Università di Trento and INFN-TIFPA, Trento, Italy
| | - Simone Orioli
- Physics Department, Università di Trento and INFN-TIFPA, Trento, Italy
| | - Riccardo Ravasio
- Institute of Physics, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Le Yan
- Kavli Institute for Theoretical Physics, University of California, Santa Barbara, CA 93106, USA
| | - Carolina Brito
- Instituto de Física, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS 91501-970, Brazil
| | - Matthieu Wyart
- Institute of Physics, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Paraskevi Gkeka
- Structure Design and Informatics, Sanofi R&D, Chilly-Mazarin, France
| | - Ivan Rivalta
- École Normale Supérieure de Lyon, Université de Lyon, CNRS, Université Claude Bernard Lyon 1, Lyon, France
| | - Giulia Palermo
- Department of Chemistry and Biochemistry, University of California, San Diego, USA; Department of Bioengineering, University of California Riverside, CA 92507, USA
| | - J Andrew McCammon
- Department of Chemistry and Biochemistry, University of California, San Diego, USA
| | - Joanna Panecka-Hofman
- Division of Biophysics, Institute of Experimental Physics, Faculty of Physics, University of Warsaw, Warsaw, Poland
| | - Rebecca C Wade
- Molecular and Cellular Modeling Group, Heidelberg Institute for Theoretical Studies (HITS) and Center for Molecular Biology (ZMBH), DKFZ-ZMBH Alliance, Heidelberg University, Heidelberg, Germany; Interdisciplinary Center for Scientific Computing (IWR), Heidelberg University, Heidelberg, Germany
| | - Antonella Di Pizio
- Leibniz-Institute for Food Systems Biology, Technical University of Munich, Munich, Germany
| | - Masha Y Niv
- Institute of Biochemistry, Food Science and Nutrition, Robert H Smith Faculty of Agriculture Food and Environment, The Hebrew University, Jerusalem, Israel
| | - Ruth Nussinov
- Frederick National Laboratory for Cancer Research, National Cancer Institute, Frederick, USA; Sackler Institute of Molecular Medicine, Department of Human Genetics and Molecular Medicine Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Chung-Jung Tsai
- Frederick National Laboratory for Cancer Research, National Cancer Institute, Frederick, USA
| | - Hyunbum Jang
- Frederick National Laboratory for Cancer Research, National Cancer Institute, Frederick, USA
| | - Dzmitry Padhorny
- Department of Applied Mathematics and Statistics, Stony Brook University, Stony Brook, NY 11794, USA
| | - Dima Kozakov
- Department of Applied Mathematics and Statistics, Stony Brook University, Stony Brook, NY 11794, USA
| | - Tom McLeish
- Department of Physics, University of York, York, UK
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Vallin J, Grantham J. The role of the molecular chaperone CCT in protein folding and mediation of cytoskeleton-associated processes: implications for cancer cell biology. Cell Stress Chaperones 2019; 24:17-27. [PMID: 30506376 PMCID: PMC6363620 DOI: 10.1007/s12192-018-0949-3] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Revised: 11/02/2018] [Accepted: 11/09/2018] [Indexed: 11/21/2022] Open
Abstract
The chaperonin-containing tailless complex polypeptide 1 (CCT) is required in vivo for the folding of newly synthesized tubulin and actin proteins and is thus intrinsically connected to all cellular processes that rely on the microtubule and actin filament components of the cytoskeleton, both of which are highly regulated and dynamic assemblies. In addition to CCT acting as a protein folding oligomer, further modes of CCT action mediated either by the CCT oligomer itself or via CCT subunits in their monomeric forms can influence processes associated with assembled actin filaments and microtubules. Thus, there is an extended functional role for CCT with regard to its major folding substrates with a complex interplay between CCT as folding machine for tubulin/actin and as a modulator of processes involving the assembled cytoskeleton. As cell division, directed cell migration, and invasion are major drivers of cancer development and rely on the microtubule and actin filament components of the cytoskeleton, CCT activity is fundamentally linked to cancer. Furthermore, the CCT oligomer also folds proteins connected to cell cycle progression and interacts with several other proteins that are linked to cancer such as tumor-suppressor proteins and regulators of the cytoskeleton, while CCT monomer function can influence cell migration. Thus, understanding CCT activity is important for many aspects of cancer cell biology and may reveal new ways to target tumor growth and invasion.
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Affiliation(s)
- Josefine Vallin
- Department of Chemistry and Molecular Biology, University of Gothenburg, 40530, Gothenburg, Sweden
| | - Julie Grantham
- Department of Chemistry and Molecular Biology, University of Gothenburg, 40530, Gothenburg, Sweden.
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18
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The structure and evolution of eukaryotic chaperonin-containing TCP-1 and its mechanism that folds actin into a protein spring. Biochem J 2018; 475:3009-3034. [DOI: 10.1042/bcj20170378] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Revised: 08/16/2018] [Accepted: 08/28/2018] [Indexed: 12/15/2022]
Abstract
Actin is folded to its native state in eukaryotic cytosol by the sequential allosteric mechanism of the chaperonin-containing TCP-1 (CCT). The CCT machine is a double-ring ATPase built from eight related subunits, CCT1–CCT8. Non-native actin interacts with specific subunits and is annealed slowly through sequential binding and hydrolysis of ATP around and across the ring system. CCT releases a folded but soft ATP-G-actin monomer which is trapped 80 kJ/mol uphill on the folding energy surface by its ATP-Mg2+/Ca2+ clasp. The energy landscape can be re-explored in the actin filament, F-actin, because ATP hydrolysis produces dehydrated and more compact ADP-actin monomers which, upon application of force and strain, are opened and closed like the elements of a spring. Actin-based myosin motor systems underpin a multitude of force generation processes in cells and muscles. We propose that the water surface of F-actin acts as a low-binding energy, directional waveguide which is recognized specifically by the myosin lever-arm domain before the system engages to form the tight-binding actomyosin complex. Such a water-mediated recognition process between actin and myosin would enable symmetry breaking through fast, low energy initial binding events. The origin of chaperonins and the subsequent emergence of the CCT–actin system in LECA (last eukaryotic common ancestor) point to the critical role of CCT in facilitating phagocytosis during early eukaryotic evolution and the transition from the bacterial world. The coupling of CCT-folding fluxes to the cell cycle, cell size control networks and cancer are discussed together with directions for further research.
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19
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Fuxreiter M. Fuzziness in Protein Interactions-A Historical Perspective. J Mol Biol 2018; 430:2278-2287. [PMID: 29477337 DOI: 10.1016/j.jmb.2018.02.015] [Citation(s) in RCA: 100] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Revised: 02/09/2018] [Accepted: 02/16/2018] [Indexed: 12/22/2022]
Abstract
The proposal that coupled folding to binding is not an obligatory mechanism for intrinsically disordered (ID) proteins was put forward 10 years ago. The notion of fuzziness implies that conformational heterogeneity can be maintained upon interactions of ID proteins, which has a functional impact either on regulated assembly or activity of the corresponding complexes. Here I review how the concept has evolved in the past decade, via increasing experimental data providing insights into the mechanisms, pathways and regulatory modes. The effects of structural diversity and transient contacts on protein assemblies have been collected and systematically analyzed (Fuzzy Complexes Database, http://protdyn-database.org). Fuzziness has also been exploited as a framework to decipher molecular organization of higher-order protein structures. Quantification of conformational heterogeneity opens exciting future perspectives for drug discovery from small molecule-ID protein interactions to supramolecular assemblies.
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Affiliation(s)
- Monika Fuxreiter
- MTA-DE Laboratory of Protein Dynamics, Department of Biochemistry and Molecular Biology, University of Debrecen, Debrecen, Hungary.
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20
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Shoemark DK, Sessions RB, Brancaccio A, Bigotti MG. Intraring allostery controls the function and assembly of a hetero-oligomeric class II chaperonin. FASEB J 2018; 32:2223-2234. [PMID: 29233859 PMCID: PMC5983026 DOI: 10.1096/fj.201701061r] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Class II chaperonins are essential multisubunit complexes that aid the folding of nonnative proteins in the cytosol of archaea and eukarya. They use energy derived from ATP to drive a series of structural rearrangements that enable polypeptides to fold within their central cavity. These events are regulated by an elaborate allosteric mechanism in need of elucidation. We employed mutagenesis and experimental analysis in concert with in silico molecular dynamics simulations and interface-binding energy calculations to investigate the class II chaperonin from Thermoplasma acidophilum. Here we describe the effects on the asymmetric allosteric mechanism and on hetero-oligomeric complex formation in a panel of mutants in the ATP-binding pocket of the α and β subunits. Our observations reveal a potential model for a nonconcerted folding mechanism optimized for protecting and refolding a range of nonnative substrates under different environmental conditions, starting to unravel the role of subunit heterogeneity in this folding machine and establishing important links with the behavior of the most complex eukaryotic chaperonins.—Shoemark, D. K., Sessions, R. B., Brancaccio, A., Bigotti, M. G. Intraring allostery controls the function and assembly of a hetero-oligomeric class II chaperonin.
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Affiliation(s)
| | | | - Andrea Brancaccio
- School of Biochemistry, University of Bristol, Bristol, United Kingdom.,Istituto di Chimica del Riconoscimento Molecolare-Consiglio Nazionale delle Ricerche (CNR), Università Cattolica del Sacro Cuore, Rome, Italy
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