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Robeson L, Casanova‐Morales N, Burgos‐Bravo F, Alfaro‐Valdés HM, Lesch R, Ramírez‐Álvarez C, Valdivia‐Delgado M, Vega M, Matute RA, Schekman R, Wilson CAM. Characterization of the interaction between the Sec61 translocon complex and ppαF using optical tweezers. Protein Sci 2024; 33:e4996. [PMID: 38747383 PMCID: PMC11094780 DOI: 10.1002/pro.4996] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Revised: 04/03/2024] [Accepted: 04/05/2024] [Indexed: 05/19/2024]
Abstract
The Sec61 translocon allows the translocation of secretory preproteins from the cytosol to the endoplasmic reticulum lumen during polypeptide biosynthesis. These proteins possess an N-terminal signal peptide (SP) which docks at the translocon. SP mutations can abolish translocation and cause diseases, suggesting an essential role for this SP/Sec61 interaction. However, a detailed biophysical characterization of this binding is still missing. Here, optical tweezers force spectroscopy was used to characterize the kinetic parameters of the dissociation process between Sec61 and the SP of prepro-alpha-factor. The unbinding parameters including off-rate constant and distance to the transition state were obtained by fitting rupture force data to Dudko-Hummer-Szabo models. Interestingly, the translocation inhibitor mycolactone increases the off-rate and accelerates the SP/Sec61 dissociation, while also weakening the interaction. Whereas the translocation deficient mutant containing a single point mutation in the SP abolished the specificity of the SP/Sec61 binding, resulting in an unstable interaction. In conclusion, we characterize quantitatively the dissociation process between the signal peptide and the translocon, and how the unbinding parameters are modified by a translocation inhibitor.
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Affiliation(s)
- Luka Robeson
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y FarmacéuticasUniversidad de ChileSantiagoChile
| | - Nathalie Casanova‐Morales
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y FarmacéuticasUniversidad de ChileSantiagoChile
- Facultad de Artes LiberalesUniversidad Adolfo IbáñezSantiagoChile
| | - Francesca Burgos‐Bravo
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y FarmacéuticasUniversidad de ChileSantiagoChile
- California Institute for Quantitative Biosciences, Howard Hughes Medical InstituteUniversity of CaliforniaBerkeleyCaliforniaUSA
| | - Hilda M. Alfaro‐Valdés
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y FarmacéuticasUniversidad de ChileSantiagoChile
| | - Robert Lesch
- Department of Molecular and Cellular Biology, Howard Hughes Medical InstituteUniversity of CaliforniaBerkeleyCaliforniaUSA
| | - Carolina Ramírez‐Álvarez
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y FarmacéuticasUniversidad de ChileSantiagoChile
| | - Mauricio Valdivia‐Delgado
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y FarmacéuticasUniversidad de ChileSantiagoChile
| | - Marcela Vega
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y FarmacéuticasUniversidad de ChileSantiagoChile
| | - Ricardo A. Matute
- Centro Integrativo de Biología y Química Aplicada (CIBQA)Universidad Bernardo O'HigginsSantiagoChile
- Division of Chemistry and Chemical EngineeringCalifornia Institute of TechnologyPasadenaCaliforniaUSA
| | - Randy Schekman
- Department of Molecular and Cellular Biology, Howard Hughes Medical InstituteUniversity of CaliforniaBerkeleyCaliforniaUSA
| | - Christian A. M. Wilson
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y FarmacéuticasUniversidad de ChileSantiagoChile
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2
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Mistry AC, Chowdhury D, Chakraborty S, Haldar S. Elucidating the novel mechanisms of molecular chaperones by single-molecule technologies. Trends Biochem Sci 2024; 49:38-51. [PMID: 37980187 DOI: 10.1016/j.tibs.2023.10.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Revised: 10/26/2023] [Accepted: 10/27/2023] [Indexed: 11/20/2023]
Abstract
Molecular chaperones play central roles in sustaining protein homeostasis and preventing protein aggregation. Most studies of these systems have been performed in bulk, providing averaged measurements, though recent single-molecule approaches have provided an in-depth understanding of the molecular mechanisms of their activities and structural rearrangements during substrate recognition. Chaperone activities have been observed to be substrate specific, with some associated with ATP-dependent structural dynamics and others via interactions with co-chaperones. This Review aims to describe the novel mechanisms of molecular chaperones as revealed by single-molecule approaches, and to provide insights into their functioning and its implications for protein homeostasis and human diseases.
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Affiliation(s)
- Ayush Chandrakant Mistry
- Department of Biology, Trivedi School of Biosciences, Ashoka University, Sonepat, Haryana 131029, India
| | - Debojyoti Chowdhury
- Department of Chemical and Biological Sciences, S.N. Bose National Center for Basic Sciences, Kolkata, West Bengal 700106, India
| | - Soham Chakraborty
- Department of Biology, Trivedi School of Biosciences, Ashoka University, Sonepat, Haryana 131029, India
| | - Shubhasis Haldar
- Department of Biology, Trivedi School of Biosciences, Ashoka University, Sonepat, Haryana 131029, India; Department of Chemical and Biological Sciences, S.N. Bose National Center for Basic Sciences, Kolkata, West Bengal 700106, India; Department of Chemistry, Ashoka University, Sonepat, Haryana 131029, India.
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3
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Wang Z, Wang M, Zhao Z, Zheng P. Quantification of carboxylate-bridged di-zinc site stability in protein due ferri by single-molecule force spectroscopy. Protein Sci 2023; 32:e4583. [PMID: 36718829 PMCID: PMC9926469 DOI: 10.1002/pro.4583] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2022] [Revised: 01/16/2023] [Accepted: 01/27/2023] [Indexed: 02/01/2023]
Abstract
Carboxylate-bridged diiron proteins belong to a protein family involved in different physiological processes. These proteins share the conservative EXXH motif, which provides the carboxylate bridge and is critical for metal binding. Here, we choose de novo-designed single-chain due ferri protein (DFsc), a four-helical protein with two EXXH motifs as a model protein, to study the stability of the carboxylate-bridged di-metal binding site. The mechanical and kinetic properties of the di-Zn site in DFsc were obtained by atomic force microscopy-based single-molecule force spectroscopy. Zn-DFsc showed a considerable rupture force of ~200 pN, while the apo-protein is mechanically labile. In addition, multiple rupture pathways were observed with different probabilities, indicating the importance of the EXXH-based carboxylate-bridged metal site. These results demonstrate carboxylate-bridged di-metal site is mechanically stable and improve our understanding of this important type of metalloprotein.
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Affiliation(s)
- Zhiyi Wang
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical EngineeringNanjing UniversityNanjingPeople's Republic of China
| | - Mengdie Wang
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical EngineeringNanjing UniversityNanjingPeople's Republic of China
| | - Zhongxin Zhao
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical EngineeringNanjing UniversityNanjingPeople's Republic of China
| | - Peng Zheng
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical EngineeringNanjing UniversityNanjingPeople's Republic of China
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4
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Rivera M, Mjaavatten A, Smith SB, Baez M, Wilson CAM. Temperature dependent mechanical unfolding and refolding of a protein studied by thermo-regulated optical tweezers. Biophys J 2023; 122:513-521. [PMID: 36587240 PMCID: PMC9941719 DOI: 10.1016/j.bpj.2022.12.034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 06/15/2022] [Accepted: 12/23/2022] [Indexed: 01/01/2023] Open
Abstract
Temperature is a useful system variable to gather kinetic and thermodynamic information from proteins. Usually, free energy and the associated entropic and enthalpic contributions are obtained by quantifying the conformational equilibrium based on melting experiments performed in bulk conditions. Such experiments are suitable only for those small single-domain proteins whose side reactions of irreversible aggregation are unlikely to occur. Here, we avoid aggregation by pulling single-protein molecules in a thermo-regulated optical tweezers. Thus, we are able to explore the temperature dependence of the thermodynamic and kinetic parameters of MJ0366 from Methanocaldococcus jannaschii at the single-molecule level. By performing force-ramp experiments between 2°C and 40°C, we found that MJ0366 has a nonlinear dependence of free energy with temperature and a specific heat change of 2.3 ± 1.2 kcal/mol∗K. These thermodynamic parameters are compatible with a two-state unfolding/refolding mechanism for MJ0366. However, the kinetics measured as a function of the temperature show a complex behavior, suggesting a three-state folding mechanism comprising a high-energy intermediate state. The combination of two perturbations, temperature and force, reveals a high-energy species in the folding mechanism of MJ0366 not detected in force-ramp experiments at constant temperature.
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Affiliation(s)
- Maira Rivera
- Institute for Biological and Medical Engineering, Schools of Engineering, Medicine and Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile; ANID - Millennium Science Initiative Program - Millennium Institute for Integrative Biology (iBio), Santiago, Chile; Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
| | | | | | - Mauricio Baez
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile.
| | - Christian A M Wilson
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile.
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5
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Rief M, Žoldák G. Single-molecule mechanical studies of chaperones and their clients. BIOPHYSICS REVIEWS 2022; 3:041301. [PMID: 38505517 PMCID: PMC10903372 DOI: 10.1063/5.0098033] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Accepted: 09/12/2022] [Indexed: 03/21/2024]
Abstract
Single-molecule force spectroscopy provides access to the mechanics of biomolecules. Recently, magnetic and laser optical tweezers were applied in the studies of chaperones and their interaction with protein clients. Various aspects of the chaperone-client interactions can be revealed based on the mechanical probing strategies. First, when a chaperone is probed under load, one can examine the inner workings of the chaperone while it interacts with and works on the client protein. Second, when protein clients are probed under load, the action of chaperones on folding clients can be studied in great detail. Such client folding studies have given direct access to observing actions of chaperones in real-time, like foldase, unfoldase, and holdase activity. In this review, we introduce the various single molecule mechanical techniques and summarize recent single molecule mechanical studies on heat shock proteins, chaperone-mediated folding on the ribosome, SNARE folding, and studies of chaperones involved in the folding of membrane proteins. An outlook on significant future developments is given.
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Affiliation(s)
- Matthias Rief
- Center for Functional Protein Assemblies (CPA), Physik Department, Technische Universität München, Ernst-Otto-Fischer-Str., 8, D-85748 Garching, Germany
| | - Gabriel Žoldák
- Center for Interdisciplinary Biosciences, Technology and Innovation Park, P. J. Šafárik University, Trieda SNP 1, 040 11 Košice, Slovakia
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6
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Determination of protein-protein interactions at the single-molecule level using optical tweezers. Q Rev Biophys 2022; 55:e8. [PMID: 35946323 DOI: 10.1017/s0033583522000075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Biomolecular interactions are at the base of all physical processes within living organisms; the study of these interactions has led to the development of a plethora of different methods. Among these, single-molecule (in singulo) experiments have become relevant in recent years because these studies can give insight into mechanisms and interactions that are hidden for ensemble-based (in multiplo) methods. The focus of this review is on optical tweezer (OT) experiments, which can be used to apply and measure mechanical forces in molecular systems. OTs are based on optical trapping, where a laser is used to exert a force on a dielectric bead; and optically trap the bead at a controllable position in all three dimensions. Different experimental approaches have been developed to study protein–protein interactions using OTs, such as: (1) refolding and unfolding in trans interaction where one protein is tethered between the beads and the other protein is in the solution; (2) constant force in cis interaction where each protein is bound to a bead, and the tension is suddenly increased. The interaction may break after some time, giving information about the lifetime of the binding at that tension. And (3) force ramp in cis interaction where each protein is attached to a bead and a ramp force is applied until the interaction breaks. With these experiments, parameters such as kinetic constants (koff, kon), affinity values (KD), energy to the transition state ΔG≠, distance to the transition state Δx≠ can be obtained. These parameters characterize the energy landscape of the interaction. Some parameters such as distance to the transition state can only be obtained from force spectroscopy experiments such as those described here.
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7
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Zhao R, Zheng S, Li Y, Zhang X, Rao D, Chun Z, Hu Y. As a novel anticancer candidate, ether extract of Dendrobium nobile overstimulates cellular protein biosynthesis to induce cell stress and autophagy. J Appl Biomed 2022; 21:23-35. [PMID: 36708715 DOI: 10.32725/jab.2022.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Accepted: 12/16/2022] [Indexed: 01/18/2023] Open
Abstract
Increasing data has confirmed the potential anticancer properties of Dendrobium, a traditional Chinese herb. However, most anticancer compositions from the plant of Dendrobium were usually extracted by high polar solvent, while weak polar compositions with excellent anticancer activity remained largely unexplored. In this study, the differences between ether extract and ethanol extract of Dendrobium nobile Lindl. on chemical components and anticancer activities were investigated, as well as the anticancer mechanisms among different extracts. The results demonstrated that the ether extract exhibited a stronger anticancer effect than ethanol extract, and its anticancer effect was mainly due to weak polar compounds rather than polysaccharides and alkaloids. Quantitative proteomics suggested that the ether extract significantly stimulated the over-expression of immature proteins, the endoplasmic reticulum stress and unfolded protein response were subsequently induced, the intracellular reactive oxygen species level was seriously elevated, and oxidative stress occurred in the meanwhile. Eventually, autophagy and apoptosis were activated to cause cell death. Our findings demonstrate that the ether extract of D. nobile is a potential candidate for anticancer drug development, and that future research on anticancer drugs derived from medicinal plants should also concentrate on weak polar compounds.
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Affiliation(s)
- Ruoxi Zhao
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China.,Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing, China
| | - Shigang Zheng
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China.,Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing, China
| | - Ying Li
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Xueqin Zhang
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Dan Rao
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Ze Chun
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China.,Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing, China
| | - Yadong Hu
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China.,Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing, China
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8
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Li J, Li H. New insights into the folding–unfolding mechanism and conformations of cytochrome C. Chem Sci 2022; 13:7498-7508. [PMID: 35872809 PMCID: PMC9241957 DOI: 10.1039/d2sc01126c] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Accepted: 05/29/2022] [Indexed: 11/21/2022] Open
Abstract
Optical trapping experiments offer new insights into the folding and unfolding of cytochrome C.
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Affiliation(s)
- Jiayu Li
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, BC V6T 1Z1, Canada
| | - Hongbin Li
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, BC V6T 1Z1, Canada
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9
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Rivera M, Hao Y, Maillard RA, Baez M. Mechanical unfolding of a knotted protein unveils the kinetic and thermodynamic consequences of threading a polypeptide chain. Sci Rep 2020; 10:9562. [PMID: 32533020 PMCID: PMC7292828 DOI: 10.1038/s41598-020-66258-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Accepted: 05/12/2020] [Indexed: 12/21/2022] Open
Abstract
Knots are remarkable topological features in nature. The presence of knots in crystallographic structures of proteins have stimulated considerable research to determine the kinetic and thermodynamic consequences of threading a polypeptide chain. By mechanically manipulating MJ0366, a small single domain protein harboring a shallow trefoil knot, we allow the protein to refold from either the knotted or the unknotted denatured state to characterize the free energy profile associated to both folding pathways. By comparing the stability of the native state with reference to the knotted and unknotted denatured state we find that knotting the polypeptide chain of MJ0366 increase the folding energy barrier in a magnitude close to the energy cost of forming a knot randomly in the denatured state. These results support that a protein knot can be formed during a single cooperative step of folding but occurs at the expenses of a large increment on the free energy barrier.
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Affiliation(s)
- Maira Rivera
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
| | - Yuxin Hao
- Department of Chemistry, Georgetown University, Washington, DC, 20057, USA
| | - Rodrigo A Maillard
- Department of Chemistry, Georgetown University, Washington, DC, 20057, USA.
| | - Mauricio Baez
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile.
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10
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Casanova-Morales N, Quiroga-Roger D, Alfaro-Valdés HM, Alavi Z, Lagos-Espinoza MIA, Zocchi G, Wilson CAM. Mechanical properties of BiP protein determined by nano-rheology. Protein Sci 2019; 27:1418-1426. [PMID: 29696702 DOI: 10.1002/pro.3432] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Revised: 04/06/2018] [Accepted: 04/19/2018] [Indexed: 02/01/2023]
Abstract
Immunoglobulin Binding Protein (BiP) is a chaperone and molecular motor belonging to the Hsp70 family, involved in the regulation of important biological processes such as synthesis, folding and translocation of proteins in the Endoplasmic Reticulum. BiP has two highly conserved domains: the N-terminal Nucleotide-Binding Domain (NBD), and the C-terminal Substrate-Binding Domain (SBD), connected by a hydrophobic linker. ATP binds and it is hydrolyzed to ADP in the NBD, and BiP's extended polypeptide substrates bind in the SBD. Like many molecular motors, BiP function depends on both structural and catalytic properties that may contribute to its performance. One novel approach to study the mechanical properties of BiP considers exploring the changes in the viscoelastic behavior upon ligand binding, using a technique called nano-rheology. This technique is essentially a traditional rheology experiment, in which an oscillatory force is directly applied to the protein under study, and the resulting average deformation is measured. Our results show that the folded state of the protein behaves like a viscoelastic material, getting softer when it binds nucleotides- ATP, ADP, and AMP-PNP-, but stiffer when binding HTFPAVL peptide substrate. Also, we observed that peptide binding dramatically increases the affinity for ADP, decreasing it dissociation constant (KD ) around 1000 times, demonstrating allosteric coupling between SBD and NBD domains.
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Affiliation(s)
- Nathalie Casanova-Morales
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, 8380494, Chile
| | - Diego Quiroga-Roger
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, 8380494, Chile
| | - Hilda M Alfaro-Valdés
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, 8380494, Chile
| | - Zahra Alavi
- Department of Physics and Astronomy, University of California - Los Angeles, Los Angeles, California, 90095, US.,Department of Physics, Loyola Marymount University, Los Angeles, California, 90045, US
| | - Miguel I A Lagos-Espinoza
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, 8380494, Chile
| | - Giovanni Zocchi
- Department of Physics and Astronomy, University of California - Los Angeles, Los Angeles, California, 90095, US
| | - Christian A M Wilson
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, 8380494, Chile
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11
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Schönfelder J, Alonso-Caballero A, De Sancho D, Perez-Jimenez R. The life of proteins under mechanical force. Chem Soc Rev 2018; 47:3558-3573. [PMID: 29473060 DOI: 10.1039/c7cs00820a] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Although much of our understanding of protein folding comes from studies of isolated protein domains in bulk, in the cellular environment the intervention of external molecular machines is essential during the protein life cycle. During the past decade single molecule force spectroscopy techniques have been extremely useful to deepen our understanding of these interventional molecular processes, as they allow for monitoring and manipulating mechanochemical events in individual protein molecules. Here, we review some of the critical steps in the protein life cycle, starting with the biosynthesis of the nascent polypeptide chain in the ribosome, continuing with the folding supported by chaperones and the translocation into different cell compartments, and ending with proteolysis in the proteasome. Along these steps, proteins experience molecular forces often combined with chemical transformations, affecting their folding and structure, which are measured or mimicked in the laboratory by the application of force with a single molecule apparatus. These mechanochemical reactions can potentially be used as targets for fighting against diseases. Inspired by these insightful experiments, we devise an outlook on the emerging field of mechanopharmacology, which reflects an alternative paradigm for drug design.
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12
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Nillegoda NB, Wentink AS, Bukau B. Protein Disaggregation in Multicellular Organisms. Trends Biochem Sci 2018; 43:285-300. [PMID: 29501325 DOI: 10.1016/j.tibs.2018.02.003] [Citation(s) in RCA: 79] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Revised: 01/29/2018] [Accepted: 02/01/2018] [Indexed: 12/13/2022]
Abstract
Protein aggregates are formed in cells with profoundly perturbed proteostasis, where the generation of misfolded proteins exceeds the cellular refolding and degradative capacity. They are a hallmark of protein conformational disorders and aged and/or environmentally stressed cells. Protein aggregation is a reversible process in vivo, which counteracts proteotoxicities derived from aggregate persistence, but the chaperone machineries involved in protein disaggregation in Metazoa were uncovered only recently. Here we highlight recent advances in the mechanistic understanding of the major protein disaggregation machinery mediated by the Hsp70 chaperone system and discuss emerging alternative disaggregation activities in multicellular organisms.
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Affiliation(s)
- Nadinath B Nillegoda
- Center for Molecular Biology of Heidelberg University (ZMBH), Im Neuenheimer Feld 282, 69120 Heidelberg, Germany; German Cancer Research Center (DKFZ), DKFZ-ZMBH Alliance, Heidelberg, Germany.
| | - Anne S Wentink
- Center for Molecular Biology of Heidelberg University (ZMBH), Im Neuenheimer Feld 282, 69120 Heidelberg, Germany
| | - Bernd Bukau
- Center for Molecular Biology of Heidelberg University (ZMBH), Im Neuenheimer Feld 282, 69120 Heidelberg, Germany; German Cancer Research Center (DKFZ), DKFZ-ZMBH Alliance, Heidelberg, Germany.
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