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Neupane K, Narayan A, Sen Mojumdar S, Adhikari G, Garen CR, Woodside MT. Direct observation of prion-like propagation of protein misfolding templated by pathogenic mutants. Nat Chem Biol 2024:10.1038/s41589-024-01672-8. [PMID: 39009686 DOI: 10.1038/s41589-024-01672-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2023] [Accepted: 06/06/2024] [Indexed: 07/17/2024]
Abstract
Many neurodegenerative diseases feature misfolded proteins that propagate via templated conversion of natively folded molecules. However, crucial questions about how such prion-like conversion occurs and what drives it remain unsolved, partly because technical challenges have prevented direct observation of conversion for any protein. We observed prion-like conversion in single molecules of superoxide dismutase-1 (SOD1), whose misfolding is linked to amyotrophic lateral sclerosis. Tethering pathogenic misfolded SOD1 mutants to wild-type molecules held in optical tweezers, we found that the mutants vastly increased misfolding of the wild-type molecule, inducing multiple misfolded isoforms. Crucially, the pattern of misfolding was the same in the mutant and converted wild-type domains and varied when the misfolded mutant was changed, reflecting the templating effect expected for prion-like conversion. Ensemble measurements showed decreased enzymatic activity in tethered heterodimers as conversion progressed, mirroring the single-molecule results. Antibodies sensitive to disease-specific epitopes bound to the converted protein, implying that conversion produced disease-relevant misfolded conformers.
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Affiliation(s)
- Krishna Neupane
- Department of Physics, University of Alberta, Edmonton, Alberta, Canada
| | - Abhishek Narayan
- Department of Physics, University of Alberta, Edmonton, Alberta, Canada
| | - Supratik Sen Mojumdar
- Department of Physics, University of Alberta, Edmonton, Alberta, Canada
- Department of Chemistry, Indian Institute of Technology Palakkad, Palakkad, India
| | - Gaurav Adhikari
- Department of Physics, University of Alberta, Edmonton, Alberta, Canada
| | - Craig R Garen
- Department of Physics, University of Alberta, Edmonton, Alberta, Canada
| | - Michael T Woodside
- Department of Physics, University of Alberta, Edmonton, Alberta, Canada.
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada.
- Li Ka Shing Institute of Virology, University of Alberta, Edmonton, Alberta, Canada.
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2
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McAlary L, Nan JR, Shyu C, Sher M, Plotkin SS, Cashman NR. Amyloidogenic regions in beta-strands II and III modulate the aggregation and toxicity of SOD1 in living cells. Open Biol 2024; 14:230418. [PMID: 38835240 DOI: 10.1098/rsob.230418] [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: 11/13/2023] [Accepted: 03/16/2024] [Indexed: 06/06/2024] Open
Abstract
Mutations in the protein superoxide dismutase-1 (SOD1) promote its misfolding and aggregation, ultimately causing familial forms of the debilitating neurodegenerative disease amyotrophic lateral sclerosis (ALS). Currently, over 220 (mostly missense) ALS-causing mutations in the SOD1 protein have been identified, indicating that common structural features are responsible for aggregation and toxicity. Using in silico tools, we predicted amyloidogenic regions in the ALS-associated SOD1-G85R mutant, finding seven regions throughout the structure. Introduction of proline residues into β-strands II (I18P) or III (I35P) reduced the aggregation propensity and toxicity of SOD1-G85R in cells, significantly more so than proline mutations in other amyloidogenic regions. The I18P and I35P mutations also reduced the capability of SOD1-G85R to template onto previously formed non-proline mutant SOD1 aggregates as measured by fluorescence recovery after photobleaching. Finally, we found that, while the I18P and I35P mutants are less structurally stable than SOD1-G85R, the proline mutants are less aggregation-prone during proteasome inhibition, and less toxic to cells overall. Our research highlights the importance of a previously underappreciated SOD1 amyloidogenic region in β-strand II (15QGIINF20) to the aggregation and toxicity of SOD1 in ALS mutants, and suggests that β-strands II and III may be good targets for the development of SOD1-associated ALS therapies.
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Affiliation(s)
- Luke McAlary
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, BC, Canada
- Department of Physics and Astronomy, University of British Columbia, Vancouver, BC, Canada
| | - Jeremy R Nan
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, BC, Canada
| | - Clay Shyu
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, BC, Canada
| | - Mine Sher
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, BC, Canada
| | - Steven S Plotkin
- Department of Physics and Astronomy, University of British Columbia, Vancouver, BC, Canada
- Genome Sciences and Technology Program, University of British Columbia, Vancouver, BC, Canada
| | - Neil R Cashman
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, BC, Canada
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3
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Tapia-Rojo R, Mora M, Garcia-Manyes S. Single-molecule magnetic tweezers to probe the equilibrium dynamics of individual proteins at physiologically relevant forces and timescales. Nat Protoc 2024; 19:1779-1806. [PMID: 38467905 PMCID: PMC7616092 DOI: 10.1038/s41596-024-00965-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Accepted: 12/18/2023] [Indexed: 03/13/2024]
Abstract
The reversible unfolding and refolding of proteins is a regulatory mechanism of tissue elasticity and signalling used by cells to sense and adapt to extracellular and intracellular mechanical forces. However, most of these proteins exhibit low mechanical stability, posing technical challenges to the characterization of their conformational dynamics under force. Here, we detail step-by-step instructions for conducting single-protein nanomechanical experiments using ultra-stable magnetic tweezers, which enable the measurement of the equilibrium conformational dynamics of single proteins under physiologically relevant low forces applied over biologically relevant timescales. We report the basic principles determining the functioning of the magnetic tweezer instrument, review the protein design strategy and the fluid chamber preparation and detail the procedure to acquire and analyze the unfolding and refolding trajectories of individual proteins under force. This technique adds to the toolbox of single-molecule nanomechanical techniques and will be of particular interest to those interested in proteins involved in mechanosensing and mechanotransduction. The procedure takes 4 d to complete, plus an additional 6 d for protein cloning and production, requiring basic expertise in molecular biology, surface chemistry and data analysis.
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Affiliation(s)
- Rafael Tapia-Rojo
- Single Molecule Mechanobiology Laboratory, The Francis Crick Institute, London, UK.
- Department of Physics, Randall Centre for Cell and Molecular Biophysics, Centre for the Physical Science of Life and London Centre for Nanotechnology, King's College London, London, UK.
| | - Marc Mora
- Single Molecule Mechanobiology Laboratory, The Francis Crick Institute, London, UK.
- Department of Physics, Randall Centre for Cell and Molecular Biophysics, Centre for the Physical Science of Life and London Centre for Nanotechnology, King's College London, London, UK.
| | - Sergi Garcia-Manyes
- Single Molecule Mechanobiology Laboratory, The Francis Crick Institute, London, UK.
- Department of Physics, Randall Centre for Cell and Molecular Biophysics, Centre for the Physical Science of Life and London Centre for Nanotechnology, King's College London, London, UK.
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4
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Ding X, Xu C, Zheng B, Yu H, Zheng P. Molecular Mechanism of Interaction between DNA Aptamer and Receptor-Binding Domain of Severe Acute Respiratory Syndrome Coronavirus 2 Variants Revealed by Steered Molecular Dynamics Simulations. Molecules 2024; 29:2215. [PMID: 38792076 PMCID: PMC11124494 DOI: 10.3390/molecules29102215] [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: 04/12/2024] [Revised: 05/07/2024] [Accepted: 05/08/2024] [Indexed: 05/26/2024] Open
Abstract
The ongoing SARS-CoV-2 pandemic has underscored the urgent need for versatile and rapidly deployable antiviral strategies. While vaccines have been pivotal in controlling the spread of the virus, the emergence of new variants continues to pose significant challenges to global health. Here, our study focuses on a novel approach to antiviral therapy using DNA aptamers, short oligonucleotides with high specificity and affinity for their targets, as potential inhibitors against the spike protein of SARS-CoV-2 variants Omicron and JN.1. Our research utilizes steered molecular dynamics (SMD) simulations to elucidate the binding mechanisms of a specifically designed DNA aptamer, AM032-4, to the receptor-binding domain (RBD) of the aforementioned variants. The simulations reveal detailed molecular insights into the aptamer-RBD interaction, demonstrating the aptamer's potential to maintain effective binding in the face of rapid viral evolution. Our work not only demonstrates the dynamic interaction between aptamer-RBD for possible antiviral therapy but also introduces a computational method to study aptamer-protein interactions.
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Affiliation(s)
- Xuan Ding
- Department of Biomedical Engineering, College of Engineering and Applied Sciences, Nanjing University, Nanjing 210093, China
- State Key Laboratory of Analytical Chemistry for Life Science, Nanjing University, Nanjing 210093, China
- School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China
| | - Chao Xu
- School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China
| | - Bin Zheng
- School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China
| | - Hanyang Yu
- Department of Biomedical Engineering, College of Engineering and Applied Sciences, Nanjing University, Nanjing 210093, China
| | - Peng Zheng
- School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China
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Liu B, Dou J, Cao J. Nuclear respiratory factor 1 regulates super enhancer-controlled SPIDR to protect hepatocellular carcinoma cells from oxidative stress. BMC Gastroenterol 2024; 24:97. [PMID: 38438958 PMCID: PMC10913589 DOI: 10.1186/s12876-024-03183-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Accepted: 02/20/2024] [Indexed: 03/06/2024] Open
Abstract
BACKGROUND Cellular response to oxidative stress plays significant roles in hepatocellular carcinoma (HCC) development, yet the exact mechanism by which HCC cells respond to oxidative stress remains poorly understood. This study aimed to investigate the role and mechanism of super enhancer (SE)-controlled genes in oxidative stress response of HCC cells. METHODS The GSE112221 dataset was used to identify SEs by HOMER. Functional enrichment of SE-controlled genes was performed by Metascape. Transcription factors were predicted using HOMER. Prognosis analysis was conducted using the Kaplan-Meier Plotter website. Expression correlation analysis was performed using the Tumor Immune Estimation Resource web server. NRF1 and SPIDR expression in HCC and normal liver tissues was analyzed based on the TCGA-LIHC dataset. ChIP-qPCR was used to detect acetylation of lysine 27 on histone 3 (H3K27ac) levels of SE regions of genes, and the binding of NRF1 to the SE of SPIDR. To mimic oxidative stress, HepG2 and Hep3B cells were stimulated with H2O2. The effects of NRF1 and SPIDR on the oxidative stress response of HCC cells were determined by the functional assays. RESULTS A total of 318 HCC-specific SE-controlled genes were identified. The functions of these genes was significant association with oxidative stress response. SPIDR and RHOB were enriched in the "response to oxidative stress" term and were chosen for validation. SE regions of SPIDR and RHOB exhibited strong H3K27ac modification, which was significantly inhibited by JQ1. JQ1 treatment suppressed the expression of SPIDR and RHOB, and increased reactive oxygen species (ROS) levels in HCC cells. TEAD2, TEAD3, NRF1, HINFP and TCFL5 were identified as potential transcription factors for HCC-specific SE-controlled genes related to oxidative stress response. The five transcription factors were positively correlated with SPIDR expression, with the highest correlation coefficient for NRF1. NRF1 and SPIDR expression was up-regulated in HCC tissues and cells. NRF1 activated SPIDR transcription by binding to its SE. Silencing SPIDR or NRF1 significantly promoted ROS accumulation in HCC cells. Under oxidative stress, silencing SPIDR or NRF1 increased ROS, malondialdehyde (MDA) and γH2AX levels, and decreased superoxide dismutase (SOD) levels and cell proliferation of HCC cells. Furthermore, overexpression of SPIDR partially offset the effects of NRF1 silencing on ROS, MDA, SOD, γH2AX levels and cell proliferation of HCC cells. CONCLUSION NRF1 driven SPIDR transcription by occupying its SE, protecting HCC cells from oxidative stress-induced damage. NRF1 and SPIDR are promising biomarkers for targeting oxidative stress in the treatment of HCC.
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Affiliation(s)
- Baowang Liu
- Department of Hepatobiliary Surgery, The Third Hospital of Hebei Medical University, 050051, Shijiazhuang, Hebei, China
| | - Jian Dou
- Department of Hepatobiliary Surgery, The Third Hospital of Hebei Medical University, 050051, Shijiazhuang, Hebei, China.
| | - Jinglin Cao
- Department of Hepatobiliary Surgery, The Third Hospital of Hebei Medical University, 050051, Shijiazhuang, Hebei, China.
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6
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Foroutannejad S, Good LL, Lin C, Carter ZI, Tadesse MG, Lucius AL, Crane BR, Maillard RA. The cofactor-dependent folding mechanism of Drosophila cryptochrome revealed by single-molecule pulling experiments. Nat Commun 2023; 14:1057. [PMID: 36828841 PMCID: PMC9958137 DOI: 10.1038/s41467-023-36701-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Accepted: 02/10/2023] [Indexed: 02/26/2023] Open
Abstract
The link between cofactor binding and protein activity is well-established. However, how cofactor interactions modulate folding of large proteins remains unknown. We use optical tweezers, clustering and global fitting to dissect the folding mechanism of Drosophila cryptochrome (dCRY), a 542-residue protein that binds FAD, one of the most chemically and structurally complex cofactors in nature. We show that the first dCRY parts to fold are independent of FAD, but later steps are FAD-driven as the remaining polypeptide folds around the cofactor. FAD binds to largely unfolded intermediates, yet with association kinetics above the diffusion-limit. Interestingly, not all FAD moieties are required for folding: whereas the isoalloxazine ring linked to ribitol and one phosphate is sufficient to drive complete folding, the adenosine ring with phosphates only leads to partial folding. Lastly, we propose a dCRY folding model where regions that undergo conformational transitions during signal transduction are the last to fold.
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Affiliation(s)
| | - Lydia L Good
- Department of Chemistry, Georgetown University, Washington, DC, USA
| | - Changfan Lin
- Department of Chemistry & Chemical Biology, Cornell University, Ithaca, NY, USA
| | - Zachariah I Carter
- Department of Chemistry, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Mahlet G Tadesse
- Department of Mathematics and Statistics, Georgetown University, Washington, DC, USA
| | - Aaron L Lucius
- Department of Chemistry, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Brian R Crane
- Department of Chemistry & Chemical Biology, Cornell University, Ithaca, NY, USA
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7
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Li H. Single Molecule Force Spectroscopy Studies on Metalloproteins: Opportunities and Challenges. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023; 39:1345-1353. [PMID: 36647634 DOI: 10.1021/acs.langmuir.2c03332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Metalloproteins play important roles in a wide range of biological processes. Elucidating the mechanisms via which metalloproteins fold and constitute their metal centers is critical to the understanding of the functions and dynamics of metalloproteins. Owing to its superior force and length resolution, single-molecule force spectroscopy (SMFS) has evolved into a powerful tool to probe the unfolding and folding mechanisms of metalloproteins at the single level by forcing metalloproteins to unfold and then refold along a reaction coordinate defined by the applied stretching force. The folding of metalloproteins is complex and involves two interwound processes, the folding of the polypeptide chain and the constitution of the metal center. Experimental studies of the folding of metalloproteins are challenging. SMFS studies have allowed researchers to directly probe the folding and unfolding of metalloproteins at the single-molecule level and the effect of metal centers on the folding-unfolding energy landscape of metalloproteins. New mechanistic insights on the folding and unfolding of some metalloproteins have been obtained, demonstrating the power and unique advantages that SMFS techniques may offer. In this Perspective, using calcium-binding proteins and small iron-sulfur proteins as examples, I provide a concise overview of the information and insights that SMFS studies have provided to understand the folding and unfolding of metalloproteins. I also discuss the opportunities and challenges that are present in this fast-progressing area of research.
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Affiliation(s)
- Hongbin Li
- Department of Chemistry, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
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8
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Das B, Roychowdhury S, Mohanty P, Rizuan A, Chakraborty J, Mittal J, Chattopadhyay K. A Zn-dependent structural transition of SOD1 modulates its ability to undergo phase separation. EMBO J 2023; 42:e111185. [PMID: 36416085 PMCID: PMC9841336 DOI: 10.15252/embj.2022111185] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Revised: 10/26/2022] [Accepted: 10/31/2022] [Indexed: 11/24/2022] Open
Abstract
The misfolding and mutation of Cu/Zn superoxide dismutase (SOD1) is commonly associated with amyotrophic lateral sclerosis (ALS). SOD1 can accumulate within stress granules (SGs), a type of membraneless organelle, which is believed to form via liquid-liquid phase separation (LLPS). Using wild-type, metal-deficient, and different ALS disease mutants of SOD1 and computer simulations, we report here that the absence of Zn leads to structural disorder within two loop regions of SOD1, triggering SOD1 LLPS and amyloid formation. The addition of exogenous Zn to either metal-free SOD1 or to the severe ALS mutation I113T leads to the stabilization of the loops and impairs SOD1 LLPS and aggregation. Moreover, partial Zn-mediated inhibition of LLPS was observed for another severe ALS mutant, G85R, which shows perturbed Zn-binding. By contrast, the ALS mutant G37R, which shows reduced Cu-binding, does not undergo LLPS. In addition, SOD1 condensates induced by Zn-depletion exhibit greater cellular toxicity than aggregates formed by prolonged incubation under aggregating conditions. Overall, our work establishes a role for Zn-dependent modulation of SOD1 conformation and LLPS properties that may contribute to amyloid formation.
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Affiliation(s)
- Bidisha Das
- Structural Biology and Bioinformatics DivisionCSIR‐Indian Institute of Chemical BiologyKolkataIndia
- Academy of Scientific and Innovative Research (AcSIR)GhaziabadIndia
| | - Sumangal Roychowdhury
- Structural Biology and Bioinformatics DivisionCSIR‐Indian Institute of Chemical BiologyKolkataIndia
| | - Priyesh Mohanty
- Artie McFerrin Department of Chemical EngineeringTexas A&M UniversityCollege StationTXUSA
| | - Azamat Rizuan
- Artie McFerrin Department of Chemical EngineeringTexas A&M UniversityCollege StationTXUSA
| | - Joy Chakraborty
- Cell Biology and Physiology DivisionCSIR‐Indian Institute of Chemical BiologyKolkataIndia
| | - Jeetain Mittal
- Artie McFerrin Department of Chemical EngineeringTexas A&M UniversityCollege StationTXUSA
| | - Krishnananda Chattopadhyay
- Structural Biology and Bioinformatics DivisionCSIR‐Indian Institute of Chemical BiologyKolkataIndia
- Academy of Scientific and Innovative Research (AcSIR)GhaziabadIndia
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9
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Tapia-Rojo R, Mora M, Board S, Walker J, Boujemaa-Paterski R, Medalia O, Garcia-Manyes S. Enhanced statistical sampling reveals microscopic complexity in the talin mechanosensor folding energy landscape. NATURE PHYSICS 2023; 19:52-60. [PMID: 36660164 PMCID: PMC7614079 DOI: 10.1038/s41567-022-01808-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Statistical mechanics can describe the major conformational ensembles determining the equilibrium free-energy landscape of a folding protein. The challenge is to capture the full repertoire of low-occurrence conformations separated by high kinetic barriers that define complex landscapes. Computationally, enhanced sampling methods accelerate the exploration of molecular rare events. However, accessing the entire protein's conformational space in equilibrium experiments requires technological developments to enable extended observation times. We developed single-molecule magnetic tweezers to capture over a million individual transitions as a single talin protein unfolds and refolds under force in equilibrium. When observed at classically-probed timescales, talin folds in an apparently uncomplicated two-state manner. As the sampling time extends from minutes to days, the underlying energy landscape exhibits gradually larger signatures of complexity, involving a finite number of well-defined rare conformations. A fluctuation analysis allows us to propose plausible structures of each low-probability conformational state. The physiological relevance of each distinct conformation can be connected to the binding of the cytoskeletal protein vinculin, suggesting an extra layer of complexity in talin-mediated mechanotransduction. More generally, our experiments directly test the fundamental notion that equilibrium dynamics depend on the observation timescale.
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Affiliation(s)
- Rafael Tapia-Rojo
- Single Molecule Mechanobiology Laboratory, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, London, UK
- Department of Physics, Randall Centre for Cell and Molecular Biophysics, Centre for the Physical Science of Life and London Centre for Nanotechnology, King’s College London, Strand, WC2R 2LS London, United Kingdom
- Corresponding authors: , ,
| | - Marc Mora
- Single Molecule Mechanobiology Laboratory, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, London, UK
- Department of Physics, Randall Centre for Cell and Molecular Biophysics, Centre for the Physical Science of Life and London Centre for Nanotechnology, King’s College London, Strand, WC2R 2LS London, United Kingdom
- Corresponding authors: , ,
| | - Stephanie Board
- Single Molecule Mechanobiology Laboratory, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, London, UK
- Department of Physics, Randall Centre for Cell and Molecular Biophysics, Centre for the Physical Science of Life and London Centre for Nanotechnology, King’s College London, Strand, WC2R 2LS London, United Kingdom
| | - Jane Walker
- Single Molecule Mechanobiology Laboratory, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, London, UK
- Department of Physics, Randall Centre for Cell and Molecular Biophysics, Centre for the Physical Science of Life and London Centre for Nanotechnology, King’s College London, Strand, WC2R 2LS London, United Kingdom
| | - Rajaa Boujemaa-Paterski
- Department of Biochemistry, Zurich University, Winterhurerstrasse 190, CH-8057, Zurich, Switzerland
| | - Ohad Medalia
- Department of Biochemistry, Zurich University, Winterhurerstrasse 190, CH-8057, Zurich, Switzerland
| | - Sergi Garcia-Manyes
- Single Molecule Mechanobiology Laboratory, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, London, UK
- Department of Physics, Randall Centre for Cell and Molecular Biophysics, Centre for the Physical Science of Life and London Centre for Nanotechnology, King’s College London, Strand, WC2R 2LS London, United Kingdom
- Corresponding authors: , ,
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10
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Halma MTJ, Tuszynski JA, Wuite GJL. Optical tweezers for drug discovery. Drug Discov Today 2023; 28:103443. [PMID: 36396117 DOI: 10.1016/j.drudis.2022.103443] [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: 06/26/2022] [Revised: 09/23/2022] [Accepted: 11/09/2022] [Indexed: 11/16/2022]
Abstract
The time taken and the cost of producing novel therapeutic drugs presents a significant burden - a typical target-based drug discovery process involves computational screening of drug libraries, compound assays and expensive clinical trials. This review summarises the value of dynamic conformational information obtained by optical tweezers and how this information can target 'undruggable' proteins. Optical tweezers provide insights into the link between biological mechanisms and structural conformations, which can be used in drug discovery. Developing workflows including software and sample preparation will improve throughput, enabling adoption of optical tweezers in biopharma. As a complementary tool, optical tweezers increase the number of drug candidates, improve the understanding of a target's complex structural dynamics and elucidate interactions between compounds and their targets.
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Affiliation(s)
- Matthew T J Halma
- Department of Physics and Astronomy, Vrije Universiteit Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands; LUMICKS B.V, Paalbergweg 3, 1105 AG Amsterdam, The Netherlands
| | - Jack A Tuszynski
- Department of Physics, University of Alberta, 116 St 85 Ave, Edmonton, Alberta T6G 2R3, Canada
| | - Gijs J L Wuite
- Department of Physics and Astronomy, Vrije Universiteit Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands.
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11
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Gosset P, Camu W, Raoul C, Mezghrani A. Prionoids in amyotrophic lateral sclerosis. Brain Commun 2022; 4:fcac145. [PMID: 35783556 PMCID: PMC9242622 DOI: 10.1093/braincomms/fcac145] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Revised: 03/16/2022] [Accepted: 06/01/2022] [Indexed: 12/20/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is the third most frequent neurodegenerative disease after Alzheimer’s and Parkinson’s disease. ALS is characterized by the selective and progressive loss of motoneurons in the spinal cord, brainstem and cerebral cortex. Clinical manifestations typically occur in midlife and start with focal muscle weakness, followed by the rapid and progressive wasting of muscles and subsequent paralysis. As with other neurodegenerative diseases, the condition typically begins at an initial point and then spreads along neuroanatomical tracts. This feature of disease progression suggests the spreading of prion-like proteins called prionoids in the affected tissues, which is similar to the spread of prion observed in Creutzfeldt-Jakob disease. Intensive research over the last decade has proposed the ALS-causing gene products Cu/Zn superoxide dismutase 1, TAR DNA-binding protein of 43 kDa, and fused in sarcoma as very plausible prionoids contributing to the spread of the pathology. In this review, we will discuss the molecular and cellular mechanisms leading to the propagation of these prionoids in ALS.
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Affiliation(s)
- Philippe Gosset
- INM, Univ Montpellier, INSERM, CNRS, Montpellier 34095, France
| | - William Camu
- INM, Univ Montpellier, INSERM, CNRS, Montpellier 34095, France
| | - Cedric Raoul
- INM, Univ Montpellier, INSERM, CNRS, Montpellier 34095, France
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12
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Sarkar A, Gasic AG, Cheung MS, Morrison G. Effects of Protein Crowders and Charge on the Folding of Superoxide Dismutase 1 Variants: A Computational Study. J Phys Chem B 2022; 126:4458-4471. [PMID: 35686856 DOI: 10.1021/acs.jpcb.2c00819] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The neurodegenerative disease amyotrophic lateral sclerosis (ALS) is associated with the misfolding and aggregation of the metalloenzyme protein superoxide dismutase 1 (SOD1) via mutations that destabilize the monomer-dimer interface. In a cellular environment, crowding and electrostatic screening play essential roles in the folding and aggregation of the SOD1 monomers. Despite numerous studies on the effects of mutations on SOD1 folding, a clear understanding of the interplay between crowding, folding, and aggregation in vivo remains lacking. Using a structure-based minimal model for molecular dynamics simulations, we investigate the role of self-crowding and charge on the folding stability of SOD1 and the G41D mutant where experimentalists were intrigued by an alteration of the folding mechanism by a single point mutation from glycine to charged aspartic acid. We show that unfolded SOD1 configurations are significantly affected by charge and crowding, a finding that would be extremely costly to achieve with all-atom simulations, while the native state is not significantly altered. The mutation at residue 41 alters the interactions between proteins in the unfolded states instead of those within a protein. This paper suggests electrostatics may play an important role in the folding pathway of SOD1 and modifying the charge via mutation and ion concentration may change the dominant interactions between proteins, with potential impacts for aggregation of the mutants. This work provides a plausible reason for the alteration of the unfolded states to address why the mutant G41D causes the changes to the folding mechanism of SOD1 that have intrigued experimentalists.
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Affiliation(s)
- Atrayee Sarkar
- Department of Physics, University of Houston, Houston, Texas 77204, United States.,Center for Theoretical Biological Physics, Rice University, Houston, Texas 77005, United States
| | - Andrei G Gasic
- Center for Theoretical Biological Physics, Rice University, Houston, Texas 77005, United States
| | - Margaret S Cheung
- Department of Physics, University of Houston, Houston, Texas 77204, United States.,Center for Theoretical Biological Physics, Rice University, Houston, Texas 77005, United States.,Pacific Northwest National Laboratory, Seattle Research Center, Seattle, Washington 98109, United States
| | - Greg Morrison
- Department of Physics, University of Houston, Houston, Texas 77204, United States.,Center for Theoretical Biological Physics, Rice University, Houston, Texas 77005, United States
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13
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Trist BG, Genoud S, Roudeau S, Rookyard A, Abdeen A, Cottam V, Hare DJ, White M, Altvater J, Fifita JA, Hogan A, Grima N, Blair IP, Kysenius K, Crouch PJ, Carmona A, Rufin Y, Claverol S, Van Malderen S, Falkenberg G, Paterson DJ, Smith B, Troakes C, Vance C, Shaw CE, Al-Sarraj S, Cordwell S, Halliday G, Ortega R, Double KL. Altered SOD1 maturation and post-translational modification in amyotrophic lateral sclerosis spinal cord. Brain 2022; 145:3108-3130. [PMID: 35512359 PMCID: PMC9473357 DOI: 10.1093/brain/awac165] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 03/29/2022] [Accepted: 04/14/2022] [Indexed: 11/13/2022] Open
Abstract
Aberrant self-assembly and toxicity of wild-type and mutant superoxide dismutase 1 (SOD1) has been widely examined in silico, in vitro, and in transgenic animal models of amyotrophic lateral sclerosis (ALS). Detailed examination of the protein in disease-affected tissues from ALS patients, however, remains scarce. We employed histological, biochemical and analytical techniques to profile alterations to SOD1 protein deposition, subcellular localization, maturation and post-translational modification in post-mortem spinal cord tissues from ALS cases and controls. Tissues were dissected into ventral and dorsal spinal cord grey matter to assess the specificity of alterations within regions of motor neuron degeneration. We provide evidence of the mislocalization and accumulation of structurally-disordered, immature SOD1 protein conformers in spinal cord motor neurons of SOD1-linked and non-SOD1-linked familial ALS cases, and sporadic ALS cases, compared with control motor neurons. These changes were collectively associated with instability and mismetallation of enzymatically-active SOD1 dimers, as well as alterations to SOD1 post-translational modifications and molecular chaperones governing SOD1 maturation. Atypical changes to SOD1 protein were largely restricted to regions of neurodegeneration in ALS cases, and clearly differentiated all forms of ALS from controls. Substantial heterogeneity in the presence of these changes was also observed between ALS cases. Our data demonstrates that varying forms of SOD1 proteinopathy are a common feature of all forms of ALS, and support the presence of one or more convergent biochemical pathways leading to SOD1 proteinopathy in ALS. The majority of these alterations are specific to regions of neurodegeneration, and may therefore constitute valid targets for therapeutic development.
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Affiliation(s)
- Benjamin G Trist
- Brain and Mind Centre and School of Medical Sciences (Neuroscience), Faculty of Medicine and Health, The University of Sydney, Sydney, NSW 2006, Australia
| | - Sian Genoud
- Brain and Mind Centre and School of Medical Sciences (Neuroscience), Faculty of Medicine and Health, The University of Sydney, Sydney, NSW 2006, Australia
| | - Stéphane Roudeau
- Univ. Bordeaux, CNRS, CENBG, UMR 5797, F-33170 Gradignan, France
| | - Alexander Rookyard
- School of Life and Environmental Sciences, Faculty of Science, The University of Sydney, Sydney, NSW 2006, Australia
| | - Amr Abdeen
- Brain and Mind Centre and School of Medical Sciences (Neuroscience), Faculty of Medicine and Health, The University of Sydney, Sydney, NSW 2006, Australia
| | - Veronica Cottam
- Brain and Mind Centre and School of Medical Sciences (Neuroscience), Faculty of Medicine and Health, The University of Sydney, Sydney, NSW 2006, Australia
| | - Dominic J Hare
- School of Biosciences, The University of Melbourne, Parkville, Victoria 3010, Australia.,Atomic Medicine Initiative, University of Technology Sydney, Broadway, New South Wales 2007, Australia
| | - Melanie White
- School of Life and Environmental Sciences, Faculty of Science, The University of Sydney, Sydney, NSW 2006, Australia
| | - Jens Altvater
- Sydney Mass Spectrometry, The University of Sydney, Sydney, NSW 2006, Australia
| | - Jennifer A Fifita
- Centre for Motor Neuron Disease Research, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, New South Wales, Australia
| | - Alison Hogan
- Centre for Motor Neuron Disease Research, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, New South Wales, Australia
| | - Natalie Grima
- Centre for Motor Neuron Disease Research, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, New South Wales, Australia
| | - Ian P Blair
- Centre for Motor Neuron Disease Research, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, New South Wales, Australia
| | - Kai Kysenius
- Department of Biochemistry and Pharmacology, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Peter J Crouch
- Department of Biochemistry and Pharmacology, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Asuncion Carmona
- Univ. Bordeaux, CNRS, CENBG, UMR 5797, F-33170 Gradignan, France
| | - Yann Rufin
- Plateforme Biochimie, University of Bordeaux, France
| | | | - Stijn Van Malderen
- Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
| | - Gerald Falkenberg
- Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
| | - David J Paterson
- Australian Synchrotron, ANSTO, Clayton, Victoria 3168, Australia
| | - Bradley Smith
- Maurice Wohl Clinical Neuroscience Institute and the Institute of Psychiatry, Psychology and Neuroscience, King's College London, Camberwell, SE5 9RT, London, UK
| | - Claire Troakes
- UK Dementia Research Institute at King's College London, 5 Cutcombe Road, London, SE5 9RT, UK
| | - Caroline Vance
- Maurice Wohl Clinical Neuroscience Institute and the Institute of Psychiatry, Psychology and Neuroscience, King's College London, Camberwell, SE5 9RT, London, UK
| | - Christopher E Shaw
- UK Dementia Research Institute at King's College London, 5 Cutcombe Road, London, SE5 9RT, UK
| | - Safa Al-Sarraj
- London Neurodegenerative Diseases Brain Bank, Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, SE5 8AF, London, UK
| | - Stuart Cordwell
- School of Life and Environmental Sciences, Faculty of Science, The University of Sydney, Sydney, NSW 2006, Australia
| | - Glenda Halliday
- Brain and Mind Centre and School of Medical Sciences (Neuroscience), Faculty of Medicine and Health, The University of Sydney, Sydney, NSW 2006, Australia
| | - Richard Ortega
- Univ. Bordeaux, CNRS, CENBG, UMR 5797, F-33170 Gradignan, France
| | - Kay L Double
- Brain and Mind Centre and School of Medical Sciences (Neuroscience), Faculty of Medicine and Health, The University of Sydney, Sydney, NSW 2006, Australia
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14
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Shi S, Wu T, Zheng P. Direct Measurements of the Cobalt-thiolate Bonds Strength in Rubredoxin by Single-Molecule Force Spectroscopy. Chembiochem 2022; 23:e202200165. [PMID: 35475313 DOI: 10.1002/cbic.202200165] [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: 03/24/2022] [Revised: 04/26/2022] [Indexed: 11/07/2022]
Abstract
Cobalt is a trace transition metal. Although it is not abundant on earth, tens of cobalt-containing proteins exist in life. Moreover, the characteristic spectrum of Co(II) ion makes it a powerful probe for the characterization of metal-binding proteins through the formation of cobalt-ligand bonds. Since most of these natural and artificial cobalt-containing proteins are stable, we believe that these cobalt-ligand bonds in the protein system are also mechanically stable. To prove this, we used atomic force microscopy-based single-molecule force spectroscopy (AFM-SMFS) to directly measure the rupture force of Co(II)-thiolate bond in Co-substituted rubredoxin (CoRD). By combining the chemical denature/renature method for building metalloprotein and cysteine coupling-based polyprotein construction strategy, we successfully prepared the polyprotein sample (CoRD) n suitable for single-molecule study. Thus, we quantified the strength of Co(II)-thiolate bonds in rubredoxin with a rupture force of ~140 pN, revealing that the bond is a stable chemical bond. In addition, the Co-S bond is more labile than the Zn-S bond in proteins, similar to the result from the metal-competing titration experiment.
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Affiliation(s)
- Shengchao Shi
- Nanjing University, School of Chemistry and Chemical Engineering, CHINA
| | - Tao Wu
- Nanjing University, School of Chemistry and Chemical Engineering, CHINA
| | - Peng Zheng
- Nanjing University, School of Chemistry and Chemical Engineering, 168 Xianlin Ave, Nanjing, Jiangsu Province, 210023, Nanjing, CHINA
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15
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Abstract
Proteins have dynamic structures that undergo chain motions on time scales spanning from picoseconds to seconds. Resolving the resultant conformational heterogeneity is essential for gaining accurate insight into fundamental mechanistic aspects of the protein folding reaction. The use of high-resolution structural probes, sensitive to population distributions, has begun to enable the resolution of site-specific conformational heterogeneity at different stages of the folding reaction. Different states populated during protein folding, including the unfolded state, collapsed intermediate states, and even the native state, are found to possess significant conformational heterogeneity. Heterogeneity in protein folding and unfolding reactions originates from the reduced cooperativity of various kinds of physicochemical interactions between various structural elements of a protein, and between a protein and solvent. Heterogeneity may arise because of functional or evolutionary constraints. Conformational substates within the unfolded state and the collapsed intermediates that exchange at rates slower than the subsequent folding steps give rise to heterogeneity on the protein folding pathways. Multiple folding pathways are likely to represent distinct sequences of structure formation. Insight into the nature of the energy barriers separating different conformational states populated during (un)folding can also be obtained by resolving heterogeneity.
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Affiliation(s)
- Sandhya Bhatia
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bengaluru 560065, India.,Indian Institute of Science Education and Research, Pune 411008, India
| | - Jayant B Udgaonkar
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bengaluru 560065, India.,Indian Institute of Science Education and Research, Pune 411008, India
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16
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Abstract
Biomolecular condensates are intracellular organelles that are not bounded by membranes and often show liquid-like, dynamic material properties. They typically contain various types of proteins and nucleic acids. How the interaction of proteins and nucleic acids finally results in dynamic condensates is not fully understood. Here we use optical tweezers and fluorescence microscopy to study how the prototypical prion-like protein Fused-in-Sarcoma (FUS) condenses with individual molecules of single- and double-stranded DNA. We find that FUS adsorbs on DNA in a monolayer and hence generates an effectively sticky FUS–DNA polymer that collapses and finally forms a dynamic, reversible FUS–DNA co-condensate. We speculate that protein monolayer-based protein–nucleic acid co-condensation is a general mechanism for forming intracellular membraneless organelles. Biomolecular condensates provide distinct compartments that can localize and organize biochemistry inside cells. Recent evidence suggests that condensate formation is prevalent in the cell nucleus. To understand how different components of the nucleus interact during condensate formation is an important challenge. In particular, the physics of co-condensation of proteins together with nucleic acids remains elusive. Here we use optical tweezers to study how the prototypical prion-like protein Fused-in-Sarcoma (FUS) forms liquid-like assemblies in vitro, by co-condensing together with individual DNA molecules. Through progressive force-induced peeling of dsDNA, buffer exchange, and force measurements, we show that FUS adsorbing in a single layer on DNA effectively generates a sticky FUS–DNA polymer that can collapse to form a liquid-like FUS–DNA co-condensate. Condensation occurs at constant DNA tension for double-stranded DNA, which is a signature of phase separation. We suggest that co-condensation mediated by protein monolayer adsorption on nucleic acids is an important mechanism for intracellular compartmentalization.
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17
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Samanta N, Ribeiro SS, Becker M, Laborie E, Pollak R, Timr S, Sterpone F, Ebbinghaus S. Sequestration of Proteins in Stress Granules Relies on the In-Cell but Not the In Vitro Folding Stability. J Am Chem Soc 2021; 143:19909-19918. [PMID: 34788540 DOI: 10.1021/jacs.1c09589] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Stress granules (SGs) are among the most studied membraneless organelles that form upon heat stress (HS) to sequester unfolded, misfolded, or aggregated protein, supporting protein quality control (PQC) clearance. The folding states that are primarily associated with SGs, as well as the function of the phase separated environment in adjusting the energy landscapes, remain unknown. Here, we investigate the association of superoxide dismutase 1 (SOD1) proteins with different folding stabilities and aggregation propensities with condensates in cells, in vitro and by simulation. We find that irrespective of aggregation the folding stability determines the association of SOD1 with SGs in cells. In vitro and in silico experiments however suggest that the increased flexibility of the unfolded state constitutes only a minor driving force to associate with the dynamic biomolecular network of the condensate. Specific protein-protein interactions in the cytoplasm in comparison to SGs determine the partitioning of folding states between the respective phases during HS.
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Affiliation(s)
- Nirnay Samanta
- Institute of Physical and Theoretical Chemistry, TU Braunschweig, Rebenring 56, D-38106 Braunschweig, Germany
| | - Sara S Ribeiro
- Institute of Physical and Theoretical Chemistry, TU Braunschweig, Rebenring 56, D-38106 Braunschweig, Germany
| | - Mailin Becker
- Institute of Physical and Theoretical Chemistry, TU Braunschweig, Rebenring 56, D-38106 Braunschweig, Germany
| | - Emeline Laborie
- CNRS Laboratoire de Biochimie Théorique, Institut de Biologie Physico-Chimique, Université Paris Denis Diderot, Sorbonne Paris Cité, PSL Research University, 13 rue Pierre et Marie Curie, Paris 75005, France
| | - Roland Pollak
- Institute of Physical and Theoretical Chemistry, TU Braunschweig, Rebenring 56, D-38106 Braunschweig, Germany
| | - Stepan Timr
- CNRS Laboratoire de Biochimie Théorique, Institut de Biologie Physico-Chimique, Université Paris Denis Diderot, Sorbonne Paris Cité, PSL Research University, 13 rue Pierre et Marie Curie, Paris 75005, France.,J. Heyrovský Institute of Physical Chemistry, Czech Academy of Sciences, Dolejskova 2155/3, Prague 8 182 23, Czech Republic
| | - Fabio Sterpone
- CNRS Laboratoire de Biochimie Théorique, Institut de Biologie Physico-Chimique, Université Paris Denis Diderot, Sorbonne Paris Cité, PSL Research University, 13 rue Pierre et Marie Curie, Paris 75005, France
| | - Simon Ebbinghaus
- Institute of Physical and Theoretical Chemistry, TU Braunschweig, Rebenring 56, D-38106 Braunschweig, Germany
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18
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Timr S, Sterpone F. Computational Insights into the Unfolding of a Destabilized Superoxide Dismutase 1 Mutant. BIOLOGY 2021; 10:1240. [PMID: 34943155 PMCID: PMC8698278 DOI: 10.3390/biology10121240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Revised: 11/17/2021] [Accepted: 11/22/2021] [Indexed: 11/16/2022]
Abstract
In this work, we investigate the β-barrel of superoxide dismutase 1 (SOD1) in a mutated form, the isoleucine 35 to alanine (I35A) mutant, commonly used as a model system to decipher the role of the full-length apoSOD1 protein in amyotrophic lateral sclerosis (ALS). It is known from experiments that the mutation reduces the stability of the SOD1 barrel and makes it largely unfolded in the cell at 37 degrees Celsius. We deploy state-of-the-art computational machinery to examine the thermal destabilization of the I35A mutant by comparing two widely used force fields, Amber a99SB-disp and CHARMM36m. We find that only the latter force field, when combined with the Replica Exchange with Solute Scaling (REST2) approach, reproduces semi-quantitatively the experimentally observed shift in the melting between the original and the mutated SOD1 barrel. In addition, we analyze the unfolding process and the conformational landscape of the mutant, finding these largely similar to those of the wildtype. Nevertheless, we detect an increased presence of partially misfolded states at ambient temperatures. These states, featuring conformational changes in the region of the β-strands β4-β6, might provide a pathway for nonnative aggregation.
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Affiliation(s)
- Stepan Timr
- Laboratoire de Biochimie Théorique (UPR 9080), CNRS, Université de Paris, 13 Rue Pierre et Marie Curie, 75005 Paris, France
- Institut de Biologie Physico-Chimique, Fondation Edmond de Rothschild, PSL Research University, 13 Rue Pierre et Marie Curie, 75005 Paris, France
- J. Heyrovsky Institute of Physical Chemistry, Czech Academy of Sciences, Dolejskova 2155/3, 18223 Prague 8, Czech Republic
| | - Fabio Sterpone
- Laboratoire de Biochimie Théorique (UPR 9080), CNRS, Université de Paris, 13 Rue Pierre et Marie Curie, 75005 Paris, France
- Institut de Biologie Physico-Chimique, Fondation Edmond de Rothschild, PSL Research University, 13 Rue Pierre et Marie Curie, 75005 Paris, France
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19
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Petrosyan R, Narayan A, Woodside MT. Single-Molecule Force Spectroscopy of Protein Folding. J Mol Biol 2021; 433:167207. [PMID: 34418422 DOI: 10.1016/j.jmb.2021.167207] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 08/11/2021] [Accepted: 08/11/2021] [Indexed: 10/20/2022]
Abstract
The use of force probes to induce unfolding and refolding of single molecules through the application of mechanical tension, known as single-molecule force spectroscopy (SMFS), has proven to be a powerful tool for studying the dynamics of protein folding. Here we provide an overview of what has been learned about protein folding using SMFS, from small, single-domain proteins to large, multi-domain proteins. We highlight the ability of SMFS to measure the energy landscapes underlying folding, to map complex pathways for native and non-native folding, to probe the mechanisms of chaperones that assist with native folding, to elucidate the effects of the ribosome on co-translational folding, and to monitor the folding of membrane proteins.
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Affiliation(s)
- Rafayel Petrosyan
- Department of Physics, University of Alberta, Edmonton, AB T6G 2E1, Canada
| | - Abhishek Narayan
- Department of Physics, University of Alberta, Edmonton, AB T6G 2E1, Canada
| | - Michael T Woodside
- Department of Physics, University of Alberta, Edmonton, AB T6G 2E1, Canada
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20
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Grau I, Nowé A, Vranken W. Interpreting a black box predictor to gain insights into early folding mechanisms. Comput Struct Biotechnol J 2021; 19:4919-4930. [PMID: 34527196 PMCID: PMC8433119 DOI: 10.1016/j.csbj.2021.08.041] [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: 03/15/2021] [Revised: 08/23/2021] [Accepted: 08/26/2021] [Indexed: 11/21/2022] Open
Abstract
Protein folding and function are closely connected, but the exact mechanisms by which proteins fold remain elusive. Early folding residues (EFRs) are amino acids within a particular protein that induce the very first stages of the folding process. High-resolution EFR data are only available for few proteins, which has previously enabled the training of a protein sequence-based machine learning 'black box' predictor (EFoldMine). Such a black box approach does not allow a direct extraction of the 'early folding rules' embedded in the protein sequence, whilst such interpretation is essential to improve our understanding of how the folding process works. We here apply and investigate a novel 'grey box' approach to the prediction of EFRs from protein sequence to gain mechanistic residue-level insights into the sequence determinants of EFRs in proteins. We interpret the rule set for three datasets, a default set comprised of natural proteins, a scrambled set comprised of the scrambled default set sequences, and a set of de novo designed proteins. Finally, we relate these data to the secondary structure adopted in the folded protein and provide all information online via http://xefoldmine.bio2byte.be/, as a resource to help understand and steer early protein folding.
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Affiliation(s)
- Isel Grau
- Artificial Intelligence Laboratory, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium
| | - Ann Nowé
- Artificial Intelligence Laboratory, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium.,Interuniversity Institute of Bioinformatics in Brussels, ULB/VUB, Triomflaan, 1050 Brussels, Belgium
| | - Wim Vranken
- Artificial Intelligence Laboratory, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium.,Interuniversity Institute of Bioinformatics in Brussels, ULB/VUB, Triomflaan, 1050 Brussels, Belgium.,Structural Biology Brussels, Vrije Universiteit Brussel, Brussels 1050, Belgium.,VIB Structural Biology Research Centre, Brussels 1050, Belgium
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21
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Nie J, Tian F, Zheng B, Wang Z, Zheng P. Exploration of Metal-Ligand Coordination Bonds in Proteins by Single-molecule Force Spectroscopy. CHEM LETT 2021. [DOI: 10.1246/cl.210307] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Jingyuan Nie
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
| | - Fang Tian
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
| | - Bin Zheng
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
| | - Ziyi Wang
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
| | - Peng Zheng
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
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22
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Unfolded and intermediate states of PrP play a key role in the mechanism of action of an antiprion chaperone. Proc Natl Acad Sci U S A 2021; 118:2010213118. [PMID: 33619087 DOI: 10.1073/pnas.2010213118] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Prion and prion-like diseases involve the propagation of misfolded protein conformers. Small-molecule pharmacological chaperones can inhibit propagated misfolding, but how they interact with disease-related proteins to prevent misfolding is often unclear. We investigated how pentosan polysulfate (PPS), a polyanion with antiprion activity in vitro and in vivo, interacts with mammalian prion protein (PrP) to alter its folding. Calorimetry showed that PPS binds two sites on natively folded PrP, but one PPS molecule can bind multiple PrP molecules. Force spectroscopy measurements of single PrP molecules showed PPS stabilizes not only the native fold of PrP but also many different partially folded intermediates that are not observed in the absence of PPS. PPS also bound tightly to unfolded segments of PrP, delaying refolding. These observations imply that PPS can act through multiple possible modes, inhibiting misfolding not only by stabilizing the native fold or sequestering natively folded PrP into aggregates, as proposed previously, but also by binding to partially or fully unfolded states that play key roles in mediating misfolding. These results underline the likely importance of unfolded states as critical intermediates on the prion conversion pathway.
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23
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Dongre AV, Das S, Bellur A, Kumar S, Chandrashekarmath A, Karmakar T, Balaram P, Balasubramanian S, Balaram H. Structural basis for the hyperthermostability of an archaeal enzyme induced by succinimide formation. Biophys J 2021; 120:3732-3746. [PMID: 34302792 DOI: 10.1016/j.bpj.2021.07.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2021] [Revised: 06/18/2021] [Accepted: 07/19/2021] [Indexed: 10/20/2022] Open
Abstract
Stability of proteins from hyperthermophiles (organisms existing under boiling water conditions) enabled by a reduction of conformational flexibility is realized through various mechanisms. A succinimide (SNN) arising from the post-translational cyclization of the side chains of aspartyl/asparaginyl residues with the backbone amide -NH of the succeeding residue would restrain the torsion angle Ψ and can serve as a new route for hyperthermostability. However, such a succinimide is typically prone to hydrolysis, transforming to either an aspartyl or β-isoaspartyl residue. Here, we present the crystal structure of Methanocaldococcus jannaschii glutamine amidotransferase and, using enhanced sampling molecular dynamics simulations, address the mechanism of its increased thermostability, up to 100°C, imparted by an unexpectedly stable succinimidyl residue at position 109. The stability of SNN109 to hydrolysis is seen to arise from its electrostatic shielding by the side-chain carboxylate group of its succeeding residue Asp110, as well as through n → π∗ interactions between SNN109 and its preceding residue Glu108, both of which prevent water access to SNN. The stable succinimidyl residue induces the formation of an α-turn structure involving 13-atom hydrogen bonding, which locks the local conformation, reducing protein flexibility. The destabilization of the protein upon replacement of SNN with a Φ-restricted prolyl residue highlights the specificity of the succinimidyl residue in imparting hyperthermostability to the enzyme. The conservation of the succinimide-forming tripeptide sequence (E(N/D)(E/D)) in several archaeal GATases strongly suggests an adaptation of this otherwise detrimental post-translational modification as a harbinger of thermostability.
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Affiliation(s)
- Aparna Vilas Dongre
- Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore, India
| | - Sudip Das
- Chemistry and Physics of Materials Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore, India
| | - Asutosh Bellur
- Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore, India
| | - Sanjeev Kumar
- Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore, India; National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bangalore, India
| | - Anusha Chandrashekarmath
- Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore, India
| | - Tarak Karmakar
- Chemistry and Physics of Materials Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore, India; Department of Chemistry and Applied Biosciences, ETH Zurich, Lugano, Ticino, Switzerland; Facoltà di Informatica, Istituto di Scienze Computationali, Università della Svizzera Italiana, Lugano, Ticino, Switzerland
| | - Padmanabhan Balaram
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bangalore, India; Molecular Biophysics Unit, Indian Institute of Science, Bangalore, India
| | - Sundaram Balasubramanian
- Chemistry and Physics of Materials Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore, India.
| | - Hemalatha Balaram
- Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore, India.
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24
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From folding to function: complex macromolecular reactions unraveled one-by-one with optical tweezers. Essays Biochem 2021; 65:129-142. [PMID: 33438724 DOI: 10.1042/ebc20200024] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 12/08/2020] [Accepted: 12/11/2020] [Indexed: 12/13/2022]
Abstract
Single-molecule manipulation with optical tweezers has uncovered macromolecular behaviour hidden to other experimental techniques. Recent instrumental improvements have made it possible to expand the range of systems accessible to optical tweezers. Beyond focusing on the folding and structural changes of isolated single molecules, optical tweezers studies have evolved into unraveling the basic principles of complex molecular processes such as co-translational folding on the ribosome, kinase activation dynamics, ligand-receptor binding, chaperone-assisted protein folding, and even dynamics of intrinsically disordered proteins (IDPs). In this mini-review, we illustrate the methodological principles of optical tweezers before highlighting recent advances in studying complex protein conformational dynamics - from protein synthesis to physiological function - as well as emerging future issues that are beginning to be addressed with novel approaches.
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25
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Sannigrahi A, Chowdhury S, Das B, Banerjee A, Halder A, Kumar A, Saleem M, Naganathan AN, Karmakar S, Chattopadhyay K. The metal cofactor zinc and interacting membranes modulate SOD1 conformation-aggregation landscape in an in vitro ALS model. eLife 2021; 10:e61453. [PMID: 33825682 PMCID: PMC8087447 DOI: 10.7554/elife.61453] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2020] [Accepted: 04/01/2021] [Indexed: 12/22/2022] Open
Abstract
Aggregation of Cu-Zn superoxide dismutase (SOD1) is implicated in the motor neuron disease, amyotrophic lateral sclerosis (ALS). Although more than 140 disease mutations of SOD1 are available, their stability or aggregation behaviors in membrane environment are not correlated with disease pathophysiology. Here, we use multiple mutational variants of SOD1 to show that the absence of Zn, and not Cu, significantly impacts membrane attachment of SOD1 through two loop regions facilitating aggregation driven by lipid-induced conformational changes. These loop regions influence both the primary (through Cu intake) and the gain of function (through aggregation) of SOD1 presumably through a shared conformational landscape. Combining experimental and theoretical frameworks using representative ALS disease mutants, we develop a 'co-factor derived membrane association model' wherein mutational stress closer to the Zn (but not to the Cu) pocket is responsible for membrane association-mediated toxic aggregation and survival time scale after ALS diagnosis.
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Affiliation(s)
- Achinta Sannigrahi
- Structural Biology & Bio-Informatics Division, CSIR-Indian Institute of Chemical BiologyKolkataIndia
| | - Sourav Chowdhury
- Chemistry and Chemical Biology, Harvard UniversityCambridgeUnited States
| | - Bidisha Das
- Structural Biology & Bio-Informatics Division, CSIR-Indian Institute of Chemical BiologyKolkataIndia
- Academy of Scientific and Innovative Research (AcSIR), CSIR- Human Resource development Centre CampusGhaziabadIndia
| | | | | | - Amaresh Kumar
- School of Biological Sciences, National Institute of Science Education and Research (NISER)BhubaneswarIndia
| | - Mohammed Saleem
- School of Biological Sciences, National Institute of Science Education and Research (NISER)BhubaneswarIndia
| | - Athi N Naganathan
- Department of Biotechnology, Bhupat & Jyoti Mehta School of Biosciences, Indian Institute of Technology MadrasChennaiIndia
| | | | - Krishnananda Chattopadhyay
- Structural Biology & Bio-Informatics Division, CSIR-Indian Institute of Chemical BiologyKolkataIndia
- Academy of Scientific and Innovative Research (AcSIR), CSIR- Human Resource development Centre CampusGhaziabadIndia
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26
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The road less traveled in protein folding: evidence for multiple pathways. Curr Opin Struct Biol 2020; 66:83-88. [PMID: 33220553 DOI: 10.1016/j.sbi.2020.10.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Accepted: 10/11/2020] [Indexed: 11/23/2022]
Abstract
Free Energy Landscape theory of Protein Folding, introduced over 20 years ago, implies that a protein has many paths to the folded conformation with the lowest free energy. Despite the knowledge in principle, it has been remarkably hard to detect such pathways. The lack of such observations is primarily due to the fact that no one experimental technique can detect many parts of the protein simultaneously with the time resolution necessary to see such differences in paths. However, recent technical developments and employment of multiple experimental probes and folding prompts have illuminated multiple folding pathways in a number of proteins that had all previously been described with a single path.
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27
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Franklin JP, Azzouz M, Shaw PJ. SOD1-targeting therapies for neurodegenerative diseases: a review of current findings and future potential. Expert Opin Orphan Drugs 2020. [DOI: 10.1080/21678707.2020.1835638] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- John P. Franklin
- Sheffield Institute for Translational Neuroscience, University of Sheffield, Sheffield, UK
| | - Mimoun Azzouz
- Sheffield Institute for Translational Neuroscience, University of Sheffield, Sheffield, UK
| | - Pamela J. Shaw
- Sheffield Institute for Translational Neuroscience, University of Sheffield, Sheffield, UK
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28
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Song G, Ding X, Liu H, Yuan G, Tian F, Shi S, Yang Y, Li G, Zheng P. Single-Molecule Force Spectroscopy Reveals that the Fe-N Bond Enables Multiple Rupture Pathways of the 2Fe2S Cluster in a MitoNEET Monomer. Anal Chem 2020; 92:14783-14789. [PMID: 33048522 DOI: 10.1021/acs.analchem.0c03536] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The mitochondrial outer membrane protein, mitoNEET (mNT), is an iron-sulfur protein containing an Fe2S2(His)1(Cys)3 cluster with a unique single Fe-N bond. Previous studies have shown that this Fe(III)-N(His) bond is essential for metal cluster transfer and protein function. To further understand the effect of this unique Fe-N bond on the metal cluster and protein, we used atomic force microscopy-based single-molecule force spectroscopy (AFM-SMFS) to investigate the mechanical unfolding mechanism of an mNT monomer, focusing on the rupture pathway and kinetic stability of the cluster. We found that the Fe-N bond was the weakest point of the cluster, the rupture of which occurred first, and could be independent of the cluster break. Moreover, this Fe-N bond enabled a dynamic and labile iron-sulfur cluster, as multiple unfolding pathways of mNT with a unique Fe2S2(Cys)3 intermediate were observed accordingly.
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Affiliation(s)
- Guobin Song
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
| | - Xuan Ding
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
| | - Huaxing Liu
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
| | - Guodong Yuan
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
| | - Fang Tian
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
| | - Shengchao Shi
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
| | - Yang Yang
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
| | - Guoqiang Li
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
| | - Peng Zheng
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
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29
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Insight into the Folding and Dimerization Mechanisms of the N-Terminal Domain from Human TDP-43. Int J Mol Sci 2020; 21:ijms21176259. [PMID: 32872449 PMCID: PMC7504384 DOI: 10.3390/ijms21176259] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Revised: 08/21/2020] [Accepted: 08/25/2020] [Indexed: 02/06/2023] Open
Abstract
TAR DNA-binding protein 43 (TDP-43) is a 414-residue long nuclear protein whose deposition into intraneuronal insoluble inclusions has been associated with the onset of amyotrophic lateral sclerosis (ALS) and other diseases. This protein is physiologically a homodimer, and dimerization occurs through the N-terminal domain (NTD), with a mechanism on which a full consensus has not yet been reached. Furthermore, it has been proposed that this domain is able to affect the formation of higher molecular weight assemblies. Here, we purified this domain and carried out an unprecedented characterization of its folding/dimerization processes in solution. Exploiting a battery of biophysical approaches, ranging from FRET to folding kinetics, we identified a head-to-tail arrangement of the monomers within the dimer. We found that folding of NTD proceeds through the formation of a number of conformational states and two parallel pathways, while a subset of molecules refold slower, due to proline isomerism. The folded state appears to be inherently prone to form high molecular weight assemblies. Taken together, our results indicate that NTD is inherently plastic and prone to populate different conformations and dimeric/multimeric states, a structural feature that may enable this domain to control the assembly state of TDP-43.
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30
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Dantas LS, Viviani LG, Inague A, Piccirillo E, Rezende LD, Ronsein GE, Augusto O, Medeiros MHG, Amaral ATD, Miyamoto S. Lipid aldehyde hydrophobicity affects apo-SOD1 modification and aggregation. Free Radic Biol Med 2020; 156:157-167. [PMID: 32598986 DOI: 10.1016/j.freeradbiomed.2020.05.011] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Revised: 04/30/2020] [Accepted: 05/12/2020] [Indexed: 12/12/2022]
Abstract
Unsaturated lipids are oxidized by reactive oxygen species and enzymes, leading to the increased formation of lipid hydroperoxides and several electrophilic products. Lipid-derived electrophiles can modify macromolecules, such as proteins, resulting in the loss of function and/or aggregation. The accumulation of Cu,Zn-superoxide dismutase (SOD1) aggregates has been associated with familial cases of amyotrophic lateral sclerosis (ALS). The protein aggregation mechanisms in motor neurons remain unclear, although recent studies have shown that lipids and oxidized lipid derivatives may play roles in this process. Here, we aimed to compare the effects of different lipid aldehydes on the induction of SOD1 modifications and aggregation, in vitro. Human recombinant apo-SOD1 was incubated with 4-hydroxy-2-hexenal (HHE), 4-hydroxy-2-nonenal (HNE), 2-hexen-1-al (HEX), 2,4-nonadienal (NON), 2,4-decadienal (DEC), or secosterol aldehydes (SECO-A or SECO-B). High-molecular-weight apo-SOD1 aggregates dramatically increased in the presence of highly hydrophobic aldehydes (LogPcalc > 3). Notably, several Lys residues were modified by exposure to all aldehydes. The observed modifications were primarily observed on Lys residues located near the dimer interface (K3 and K9) and at the electrostatic loop (K122, K128, and K136). Moreover, HHE and HNE induced extensive apo-SOD1 modifications, by forming Schiff bases or Michael adducts with Lys, His, and Cys residues. However, these aldehydes were unable to induce large protein aggregates. Overall, our data shed light on the importance of lipid aldehyde hydrophobicity on the induction of apo-SOD1 aggregation and identified preferential sites of lipid aldehyde-induced modifications.
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Affiliation(s)
- Lucas S Dantas
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Lucas G Viviani
- Departamento de Química Fundamental, Instituto de Química, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Alex Inague
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Erika Piccirillo
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, SP, Brazil; Departamento de Química Fundamental, Instituto de Química, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Leandro de Rezende
- Departamento de Química Fundamental, Instituto de Química, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Graziella E Ronsein
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Ohara Augusto
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Marisa H G Medeiros
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Antonia T do Amaral
- Departamento de Química Fundamental, Instituto de Química, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Sayuri Miyamoto
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, SP, Brazil.
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31
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Medina E, Villalobos P, Hamilton GL, Komives EA, Sanabria H, Ramírez-Sarmiento CA, Babul J. Intrinsically Disordered Regions of the DNA-Binding Domain of Human FoxP1 Facilitate Domain Swapping. J Mol Biol 2020; 432:5411-5429. [PMID: 32735805 DOI: 10.1016/j.jmb.2020.07.017] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Revised: 07/21/2020] [Accepted: 07/22/2020] [Indexed: 01/01/2023]
Abstract
Forkhead box P (FoxP) proteins are unique transcription factors that spatiotemporally regulate gene expression by tethering two chromosome loci together via functional domain-swapped dimers formed through their DNA-binding domains. Further, the differential kinetics on this dimerization mechanism underlie an intricate gene regulation network at physiological conditions. Nonetheless, poor understanding of the structural dynamics and steps of the association process impedes to link the functional domain swapping to human-associated diseases. Here, we have characterized the DNA-binding domain of human FoxP1 by integrating single-molecule Förster resonance energy transfer and hydrogen-deuterium exchange mass spectrometry data with molecular dynamics simulations. Our results confirm the formation of a previously postulated domain-swapped (DS) FoxP1 dimer in solution and reveal the presence of highly populated, heterogeneous, and locally disordered dimeric intermediates along the dimer dissociation pathway. The unique features of FoxP1 provide a glimpse of how intrinsically disordered regions can facilitate domain swapping oligomerization and other tightly regulated association mechanisms relevant in biological processes.
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Affiliation(s)
- Exequiel Medina
- Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Casilla 653, Santiago 7800003, Chile
| | - Pablo Villalobos
- Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Casilla 653, Santiago 7800003, Chile
| | - George L Hamilton
- Department of Physics & Astronomy, Clemson University, Clemson, SC 29634, USA
| | - Elizabeth A Komives
- Department of Chemistry & Biochemistry, University of California San Diego, La Jolla, CA, USA
| | - Hugo Sanabria
- Department of Physics & Astronomy, Clemson University, Clemson, SC 29634, USA.
| | - César A Ramírez-Sarmiento
- Institute for Biological and Medical Engineering, Schools of Engineering, Medicine and Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile; Millennium Institute for Integrative Biology (iBio), Santiago, Chile.
| | - Jorge Babul
- Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Casilla 653, Santiago 7800003, Chile.
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32
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Timr S, Gnutt D, Ebbinghaus S, Sterpone F. The Unfolding Journey of Superoxide Dismutase 1 Barrels under Crowding: Atomistic Simulations Shed Light on Intermediate States and Their Interactions with Crowders. J Phys Chem Lett 2020; 11:4206-4212. [PMID: 32364389 DOI: 10.1021/acs.jpclett.0c00699] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
The thermal stability of the superoxide dismutase 1 protein in a crowded solution is investigated by performing enhanced sampling molecular simulations. By complementing thermal unfolding experiments done close to physiological conditions (200 mg/mL), we provide evidence that the presence of the protein crowder bovine serum albumin in different packing states has only a minor, and essentially destabilizing, effect. The finding that quinary interactions counteract the pure stabilization contribution stemming from excluded volume is rationalized here by exploring the SOD1 unfolding mechanism in microscopic detail. In agreement with recent experiments, we unveil the importance of intermediate unfolded states as well as the correlation between protein conformations and local packing with the crowders. This link helps us to elucidate why certain SOD1 mutations involved in the ALS disease reverse the stability effect of the intracellular environment.
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Affiliation(s)
- Stepan Timr
- CNRS, Université de Paris, UPR 9080, Laboratoire de Biochimie Théorique, 13 rue Pierre et Marie Curie, F-75005 Paris, France
- Institut de Biologie Physico-Chimique-Fondation Edmond de Rothschild, PSL Research University, F-75005 Paris, France
| | - David Gnutt
- Institute of Physical and Theoretical Chemistry, Technical University Braunschweig, Rebenring 56, 38106 Braunschweig, Germany
- Department of Physical Chemistry II, Ruhr University Bochum, Universitätsstrasse 150, 44801 Bochum, Germany
| | - Simon Ebbinghaus
- Institute of Physical and Theoretical Chemistry, Technical University Braunschweig, Rebenring 56, 38106 Braunschweig, Germany
- Department of Physical Chemistry II, Ruhr University Bochum, Universitätsstrasse 150, 44801 Bochum, Germany
| | - Fabio Sterpone
- CNRS, Université de Paris, UPR 9080, Laboratoire de Biochimie Théorique, 13 rue Pierre et Marie Curie, F-75005 Paris, France
- Institut de Biologie Physico-Chimique-Fondation Edmond de Rothschild, PSL Research University, F-75005 Paris, France
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33
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Kibria MG, Akazawa-Ogawa Y, Rahman N, Hagihara Y, Kuroda Y. The immunogenicity of an anti-EGFR single domain antibody (V HH) is enhanced by misfolded amorphous aggregation but not by heat-induced aggregation. Eur J Pharm Biopharm 2020; 152:164-174. [PMID: 32416134 DOI: 10.1016/j.ejpb.2020.05.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Revised: 05/07/2020] [Accepted: 05/10/2020] [Indexed: 11/30/2022]
Abstract
Amorphous aggregates of therapeutic proteins can provoke an unwanted immune response (anti-drug antibodies; ADAs), but counter-examples have led to some controversy. Amorphous aggregates can possess unique biophysical and biochemical attributes depending on both the way they are generated and the protein's biophysical/biochemical properties. Here, we examine the immunogenicity of an anti-EGFR single domain antibody (VHH) in four types of amorphous aggregates: two heat-aggregated VHH incubated at 65 °C (VHH-65) and 95 °C (VHH-95), a misfolded VHH isolated from the insoluble fraction of the E. coli lysate (VHH-Ins), and a low solubility misfolded VHH produced by miss-shuffling the SS bonds of the native VHH (VHH-Mis). Biophysical and biochemical measurements indicated that VHH was indeed natively folded, monomeric, and β-sheeted; that VHH-65 was partially unfolded and formed aggregates with a Z-average (Zave) of 771 nm; whereas VHH-95 was unfolded and formed aggregates of 1722 nm; and that both VHH-Ins and VHH-Mis were misfolded with non-native intermolecular SS bonds and formed aggregates with a Zave of 1846 nm and 1951 nm, respectively. The IgG level generated in Jcl:ICR mice determined by ELISA showed that the native VHH was barely immunogenic, VHH-95 was not immunogenic, while VHH-65 was mildly immunogenic. By contrast, the misfolded aggregates, VHH-Ins and VHH-Mis, having a Zave and an aggregation propensity similar to that of VHH-95, were highly immunogenic. These findings indicate the critical role of the biochemical and biophysical attributes of the amorphous aggregates in generating an immune response against a protein, rather than just their sizes.
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Affiliation(s)
- Md Golam Kibria
- Department of Biotechnology and Life Science, Graduate School of Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Nakamachi, Koganei-shi, Tokyo 184-8588, Japan
| | - Yoko Akazawa-Ogawa
- Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 1-8-31, Midorigaoka, Ikeda, Osaka 563-8577, Japan
| | - Nafsoon Rahman
- Department of Biotechnology and Life Science, Graduate School of Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Nakamachi, Koganei-shi, Tokyo 184-8588, Japan
| | - Yoshihisa Hagihara
- Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 1-8-31, Midorigaoka, Ikeda, Osaka 563-8577, Japan
| | - Yutaka Kuroda
- Department of Biotechnology and Life Science, Graduate School of Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Nakamachi, Koganei-shi, Tokyo 184-8588, Japan.
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Srinivasan E, Rajasekaran R. A Systematic and Comprehensive Review on Disease-Causing Genes in Amyotrophic Lateral Sclerosis. J Mol Neurosci 2020; 70:1742-1770. [PMID: 32415434 DOI: 10.1007/s12031-020-01569-w] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Accepted: 04/22/2020] [Indexed: 12/13/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder and is characterized by degeneration and axon loss from the upper motor neuron, that descends from the lower motor neuron in the brain. Over the period, assorted outcomes from medical findings, molecular pathogenesis, and structural and biophysical studies have abetted in providing thoughtful insights underlying the importance of disease-causing genes in ALS. Consequently, numerous mechanisms were proposed for the pathogenesis of ALS, considering protein mutations, aggregation, and misfolding. Besides, the answers to the majority of ALS cases that happen to be sporadic still remain obscure. The application in discovering susceptibility factors in ALS contemplating the genetic factors is to be further dissevered in the future years with innovation in research studies. Hence, this review targets in revisiting the breakthroughs on the disease-causing genes related with ALS.
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Affiliation(s)
- E Srinivasan
- Bioinformatics Lab, Department of Biotechnology, School of Bio Sciences and Technology, Vellore Institute of Technology (deemed to be university), Vellore, Tamil Nadu, 632014, India
| | - R Rajasekaran
- Bioinformatics Lab, Department of Biotechnology, School of Bio Sciences and Technology, Vellore Institute of Technology (deemed to be university), Vellore, Tamil Nadu, 632014, India.
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35
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Maffucci I, Laage D, Stirnemann G, Sterpone F. Differences in thermal structural changes and melting between mesophilic and thermophilic dihydrofolate reductase enzymes. Phys Chem Chem Phys 2020; 22:18361-18373. [DOI: 10.1039/d0cp02738c] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The thermal resistance of two homolog enzymes is investigated, with an emphasis on their local stability and flexibility, and on the possible implications regarding their reactivity.
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Affiliation(s)
- Irene Maffucci
- CNRS Laboratoire de Biochimie Théorique
- Institut de Biologie Physico-Chimique
- PSL University
- Paris
- France
| | - Damien Laage
- PASTEUR
- Département de chimie
- École Normale Supérieure
- PSL University
- Sorbonne Université
| | - Guillaume Stirnemann
- CNRS Laboratoire de Biochimie Théorique
- Institut de Biologie Physico-Chimique
- PSL University
- Paris
- France
| | - Fabio Sterpone
- CNRS Laboratoire de Biochimie Théorique
- Institut de Biologie Physico-Chimique
- PSL University
- Paris
- France
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36
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Abstract
Large proteins composed of multiple domains are abundant in all proteomes, but their folding and structural dynamics remain poorly understood. Using single-molecule force spectroscopy, we have defined how stabilizing interfaces among the domains of elongation factor G (EF-G) shape its folding pathway. Contrary to the expectation that multidomain proteins fold sequentially as they emerge from the ribosome, we find that folding cannot be completed until the full protein has been synthesized. This posttranslational folding mechanism results in a propensity for misfolding. It is dictated by an energetic coupling among domains that enables conformational flexibility crucial for EF-G function. EF-G thus provides an example of how distinct biological ends—robust folding and functionally important flexibility—come into conflict during protein biogenesis. Large proteins with multiple domains are thought to fold cotranslationally to minimize interdomain misfolding. Once folded, domains interact with each other through the formation of extensive interfaces that are important for protein stability and function. However, multidomain protein folding and the energetics of domain interactions remain poorly understood. In elongation factor G (EF-G), a highly conserved protein composed of 5 domains, the 2 N-terminal domains form a stably structured unit cotranslationally. Using single-molecule optical tweezers, we have defined the steps leading to fully folded EF-G. We find that the central domain III of EF-G is highly dynamic and does not fold upon emerging from the ribosome. Surprisingly, a large interface with the N-terminal domains does not contribute to the stability of domain III. Instead, it requires interactions with its folded C-terminal neighbors to be stably structured. Because of the directionality of protein synthesis, this energetic dependency of domain III on its C-terminal neighbors disrupts cotranslational folding and imposes a posttranslational mechanism on the folding of the C-terminal part of EF-G. As a consequence, unfolded domains accumulate during synthesis, leading to the extensive population of misfolded species that interfere with productive folding. Domain III flexibility enables large-scale conformational transitions that are part of the EF-G functional cycle during ribosome translocation. Our results suggest that energetic tuning of domain stabilities, which is likely crucial for EF-G function, complicates the folding of this large multidomain protein.
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37
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Yuan G, Liu H, Ma Q, Li X, Nie J, Zuo J, Zheng P. Single-Molecule Force Spectroscopy Reveals that Iron-Ligand Bonds Modulate Proteins in Different Modes. J Phys Chem Lett 2019; 10:5428-5433. [PMID: 31433648 DOI: 10.1021/acs.jpclett.9b01573] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The iron-amino acid interactions Fe-O(Glu/Asp), Fe-N(His), and Fe-S(Cys) are the three major iron-ligand bonds in proteins. To compare their properties in proteins, we used atomic force microscopy (AFM)-based single-molecule force spectroscopy to investigate a superoxide reductase (Fe(III)-SOR) with all three types of bonds forming an Fe(His)4CysGlu center. We first found that Apo-SOR without bound iron showed multiple unfolding pathways only from the β-barrel core. Then, using Holo-SOR with a ferric ion, we found that a single Fe-O(Glu) bond can tightly connect the flexible N-terminal fragment to the β-barrel and stabilize the whole protein, showing a complete protein unfolding scenario, while the single Fe-N(His) bond was weak and unable to provide such a stabilization. Moreover, when multiple Fe-N bonds are present, a similar stabilization effect can be achieved. Our results showed that the iron-ligand bond modulates protein structure and stability in different modes at the single-bond level.
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Affiliation(s)
- Guodong Yuan
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering , Nanjing University , Nanjing , Jiangsu 210023 , People's Republic of China
| | - Huaxing Liu
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering , Nanjing University , Nanjing , Jiangsu 210023 , People's Republic of China
| | - Qun Ma
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering , Nanjing University , Nanjing , Jiangsu 210023 , People's Republic of China
| | - Xi Li
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering , Nanjing University , Nanjing , Jiangsu 210023 , People's Republic of China
| | - Jingyuan Nie
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering , Nanjing University , Nanjing , Jiangsu 210023 , People's Republic of China
| | - Jinglin Zuo
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering , Nanjing University , Nanjing , Jiangsu 210023 , People's Republic of China
| | - Peng Zheng
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering , Nanjing University , Nanjing , Jiangsu 210023 , People's Republic of China
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38
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Wang Z, Jumper JM, Freed KF, Sosnick TR. On the Interpretation of Force-Induced Unfolding Studies of Membrane Proteins Using Fast Simulations. Biophys J 2019; 117:1429-1441. [PMID: 31587831 DOI: 10.1016/j.bpj.2019.09.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2019] [Revised: 08/25/2019] [Accepted: 09/12/2019] [Indexed: 11/25/2022] Open
Abstract
Single-molecule force spectroscopy has proven extremely beneficial in elucidating folding pathways for membrane proteins. Here, we simulate these measurements, conducting hundreds of unfolding trajectories using our fast Upside algorithm for slow enough speeds to reproduce key experimental features that may be missed using all-atom methods. The speed also enables us to determine the logarithmic dependence of pulling velocities on the rupture levels to better compare to experimental values. For simulations of atomic force microscope measurements in which force is applied vertically to the C-terminus of bacteriorhodopsin, we reproduce the major experimental features including even the back-and-forth unfolding of single helical turns. When pulling laterally on GlpG to mimic the experiment, we observe quite different behavior depending on the stiffness of the spring. With a soft spring, as used in the experimental studies with magnetic tweezers, the force remains nearly constant after the initial unfolding event, and a few pathways and a high degree of cooperativity are observed in both the experiment and simulation. With a stiff spring, however, the force drops to near zero after each major unfolding event, and numerous intermediates are observed along a wide variety of pathways. Hence, the mode of force application significantly alters the perception of the folding landscape, including the number of intermediates and the degree of folding cooperativity, important issues that should be considered when designing experiments and interpreting unfolding data.
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Affiliation(s)
- Zongan Wang
- Department of Chemistry, James Franck Institute, The University of Chicago, Chicago, Illinois; Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, Illinois
| | - John M Jumper
- Department of Chemistry, James Franck Institute, The University of Chicago, Chicago, Illinois; Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, Illinois
| | - Karl F Freed
- Department of Chemistry, James Franck Institute, The University of Chicago, Chicago, Illinois.
| | - Tobin R Sosnick
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, Illinois; Institute for Biophysical Dynamics, The University of Chicago, Chicago, Illinois.
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39
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Li Q, Scholl ZN, Marszalek PE. Unraveling the Mechanical Unfolding Pathways of a Multidomain Protein: Phosphoglycerate Kinase. Biophys J 2019; 115:46-58. [PMID: 29972811 DOI: 10.1016/j.bpj.2018.05.028] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Revised: 03/31/2018] [Accepted: 05/21/2018] [Indexed: 01/12/2023] Open
Abstract
Phosphoglycerate kinase (PGK) is a highly conserved enzyme that is crucial for glycolysis. PGK is a monomeric protein composed of two similar domains and has been the focus of many studies for investigating interdomain interactions within the native state and during folding. Previous studies used traditional biophysical methods (such as circular dichroism, tryptophan fluorescence, and NMR) to measure signals over a large ensemble of molecules, which made it difficult to observe transient changes in stability or structure during unfolding and refolding of single molecules. Here, we unfold single molecules of PGK using atomic force spectroscopy and steered molecular dynamic computer simulations to examine the conformational dynamics of PGK during its unfolding process. Our results show that after the initial forced separation of its domains, yeast PGK (yPGK) does not follow a single mechanical unfolding pathway; instead, it stochastically follows two distinct pathways: unfolding from the N-terminal domain or unfolding from the C-terminal domain. The truncated yPGK N-terminal domain unfolds via a transient intermediate, whereas the structurally similar isolated C-terminal domain has no detectable intermediates throughout its mechanical unfolding process. The N-terminal domain in the full-length yPGK displays a strong unfolding intermediate 13% of the time, whereas the truncated domain (yPGKNT) transitions through the intermediate 81% of the time. This effect indicates that the mechanical properties of yPGK cannot be simply deduced from the mechanical properties of its constituents. We also find that Escherichia coli PGK is significantly less mechanically stable as compared to yPGK, contrary to bulk unfolding measurements. Our results support the growing body of observations that the folding behavior of multidomain proteins is difficult to predict based solely on the studies of isolated domains.
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Affiliation(s)
- Qing Li
- Center for Biologically Inspired Materials and Material Systems, Department of Mechanical Engineering and Materials Science, Pratt School of Engineering, Duke University, Durham, North Carolina.
| | - Zackary N Scholl
- Program in Computational Biology and Bioinformatics, Department of Mechanical Engineering and Materials Science, Pratt School of Engineering, Duke University, Durham, North Carolina.
| | - Piotr E Marszalek
- Center for Biologically Inspired Materials and Material Systems, Department of Mechanical Engineering and Materials Science, Pratt School of Engineering, Duke University, Durham, North Carolina.
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40
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Complex dynamics under tension in a high-efficiency frameshift stimulatory structure. Proc Natl Acad Sci U S A 2019; 116:19500-19505. [PMID: 31409714 DOI: 10.1073/pnas.1905258116] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Specific structures in mRNA can stimulate programmed ribosomal frameshifting (PRF). PRF efficiency can vary enormously between different stimulatory structures, but the features that lead to efficient PRF stimulation remain uncertain. To address this question, we studied the structural dynamics of the frameshift signal from West Nile virus (WNV), which stimulates -1 PRF at very high levels and has been proposed to form several different structures, including mutually incompatible pseudoknots and a double hairpin. Using optical tweezers to apply tension to single mRNA molecules, mimicking the tension applied by the ribosome during PRF, we found that the WNV frameshift signal formed an unusually large number of different metastable structures, including all of those previously proposed. From force-extension curve measurements, we mapped 2 mutually exclusive pathways for the folding, each encompassing multiple intermediates. We identified the intermediates in each pathway from length changes and the effects of antisense oligomers blocking formation of specific contacts. Intriguingly, the number of transitions between the different conformers of the WNV frameshift signal was maximal in the range of forces applied by the ribosome during -1 PRF. Furthermore, the occupancy of the pseudoknotted conformations was far too low for static pseudoknots to account for the high levels of -1 PRF. These results support the hypothesis that conformational heterogeneity plays a key role in frameshifting and suggest that transitions between different conformers under tension are linked to efficient PRF stimulation.
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41
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Micsonai A, Wien F, Bulyáki É, Kun J, Moussong É, Lee YH, Goto Y, Réfrégiers M, Kardos J. BeStSel: a web server for accurate protein secondary structure prediction and fold recognition from the circular dichroism spectra. Nucleic Acids Res 2019; 46:W315-W322. [PMID: 29893907 PMCID: PMC6031044 DOI: 10.1093/nar/gky497] [Citation(s) in RCA: 662] [Impact Index Per Article: 132.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2018] [Accepted: 05/22/2018] [Indexed: 12/31/2022] Open
Abstract
Circular dichroism (CD) spectroscopy is a widely used method to study the protein secondary structure. However, for decades, the general opinion was that the correct estimation of β-sheet content is challenging because of the large spectral and structural diversity of β-sheets. Recently, we showed that the orientation and twisting of β-sheets account for the observed spectral diversity, and developed a new method to estimate accurately the secondary structure (PNAS, 112, E3095). BeStSel web server provides the Beta Structure Selection method to analyze the CD spectra recorded by conventional or synchrotron radiation CD equipment. Both normalized and measured data can be uploaded to the server either as a single spectrum or series of spectra. The originality of BeStSel is that it carries out a detailed secondary structure analysis providing information on eight secondary structure components including parallel-β structure and antiparallel β-sheets with three different groups of twist. Based on these, it predicts the protein fold down to the topology/homology level of the CATH protein fold classification. The server also provides a module to analyze the structures deposited in the PDB for BeStSel secondary structure contents in relation to Dictionary of Secondary Structure of Proteins data. The BeStSel server is freely accessible at http://bestsel.elte.hu.
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Affiliation(s)
- András Micsonai
- ELTE NAP Neuroimmunology Research Group, Department of Biochemistry, ELTE Eötvös Loránd University, Budapest H-1117, Hungary
| | - Frank Wien
- Synchrotron SOLEIL, Gif-sur-Yvette 91192, France
| | - Éva Bulyáki
- ELTE NAP Neuroimmunology Research Group, Department of Biochemistry, ELTE Eötvös Loránd University, Budapest H-1117, Hungary
| | - Judit Kun
- ELTE NAP Neuroimmunology Research Group, Department of Biochemistry, ELTE Eötvös Loránd University, Budapest H-1117, Hungary
| | - Éva Moussong
- ELTE NAP Neuroimmunology Research Group, Department of Biochemistry, ELTE Eötvös Loránd University, Budapest H-1117, Hungary
| | - Young-Ho Lee
- Institute for Protein Research, Osaka University, Osaka 565-0871, Japan
| | - Yuji Goto
- Institute for Protein Research, Osaka University, Osaka 565-0871, Japan
| | | | - József Kardos
- ELTE NAP Neuroimmunology Research Group, Department of Biochemistry, ELTE Eötvös Loránd University, Budapest H-1117, Hungary
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42
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Cohen NR, Zitzewitz JA, Bilsel O, Matthews CR. Nonnative structure in a peptide model of the unfolded state of superoxide dismutase 1 (SOD1): Implications for ALS-linked aggregation. J Biol Chem 2019; 294:13708-13717. [PMID: 31341015 DOI: 10.1074/jbc.ra119.008765] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Revised: 06/28/2019] [Indexed: 12/13/2022] Open
Abstract
Dozens of mutations throughout the sequence of the gene encoding superoxide dismutase 1 (SOD1) have been linked to toxic protein aggregation in the neurodegenerative disease amyotrophic lateral sclerosis (ALS). A parsimonious explanation for numerous genotypes resulting in a common phenotype would be mutation-induced perturbation of the folding free-energy surface that increases the populations of high-energy states prone to aggregation. The absence of intermediates in the folding of monomeric SOD1 suggests that the unfolded ensemble is a potential source of aggregation. To test this hypothesis, here we dissected SOD1 into a set of peptides end-labeled with FRET probes to model the local behavior of the corresponding sequences in the unfolded ensemble. Using time-resolved FRET, we observed that the peptide corresponding to the Loop VII-β8 sequence at the SOD1 C terminus was uniquely sensitive to denaturant. Utilizing a two-dimensional form of maximum entropy modeling, we demonstrate that the sensitivity to denaturant is the surprising result of a two-state-like transition from a compact to an expanded state. Variations of the peptide sequence revealed that the compact state involves a nonnative interaction between the disordered N terminus and the hydrophobic C terminus of the peptide. This nonnative intramolecular structure could serve as a precursor for intermolecular association and result in aggregation associated with ALS. We propose that this precursor would provide a common molecular target for therapeutic intervention in the dozens of ALS-linked SOD1 mutations.
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Affiliation(s)
- Noah R Cohen
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts 01605
| | - Jill A Zitzewitz
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts 01605
| | - Osman Bilsel
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts 01605
| | - C Robert Matthews
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts 01605
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43
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Banks CJ, Andersen JL. Mechanisms of SOD1 regulation by post-translational modifications. Redox Biol 2019; 26:101270. [PMID: 31344643 PMCID: PMC6658992 DOI: 10.1016/j.redox.2019.101270] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Revised: 06/28/2019] [Accepted: 07/03/2019] [Indexed: 12/18/2022] Open
Abstract
SOD1 is commonly known for its ROS scavenging activity, but recent work has uncovered additional roles in modulating metabolism, maintaining redox balance, and regulating transcription. This new paradigm of expanded SOD1 function raises questions regarding the regulation of SOD1 and the cellular partitioning of its biological roles. Despite decades of research on SOD1, much of which focuses on its pathogenic role in amyotrophic lateral sclerosis, relatively little is known about its regulation by post-translational modifications (PTMs). However, over the last decade, advancements in mass spectrometry have led to a boom in PTM discovery across the proteome, which has also revealed new mechanisms of SOD1 regulation by PTMs and an array of SOD1 PTMs with high likelihood of biological function. In this review, we address emerging mechanisms of SOD1 regulation by post-translational modifications, many of which begin to shed light on how the various functions of SOD1 are regulated within the cell.
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Affiliation(s)
- C J Banks
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT, USA
| | - J L Andersen
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT, USA.
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44
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Deng Y, Wu T, Wang M, Shi S, Yuan G, Li X, Chong H, Wu B, Zheng P. Enzymatic biosynthesis and immobilization of polyprotein verified at the single-molecule level. Nat Commun 2019; 10:2775. [PMID: 31235796 PMCID: PMC6591319 DOI: 10.1038/s41467-019-10696-x] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Accepted: 05/23/2019] [Indexed: 11/09/2022] Open
Abstract
The recent development of chemical and bio-conjugation techniques allows for the engineering of various protein polymers. However, most of the polymerization process is difficult to control. To meet this challenge, we develop an enzymatic procedure to build polyprotein using the combination of a strict protein ligase OaAEP1 (Oldenlandia affinis asparaginyl endopeptidases 1) and a protease TEV (tobacco etch virus). We firstly demonstrate the use of OaAEP1-alone to build a sequence-uncontrolled ubiquitin polyprotein and covalently immobilize the coupled protein on the surface. Then, we construct a poly-metalloprotein, rubredoxin, from the purified monomer. Lastly, we show the feasibility of synthesizing protein polymers with rationally-controlled sequences by the synergy of the ligase and protease, which are verified by protein unfolding using atomic force microscopy-based single-molecule force spectroscopy (AFM-SMFS). Thus, this study provides a strategy for polyprotein engineering and immobilization.
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Affiliation(s)
- Yibing Deng
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu, 210023, P. R. China
| | - Tao Wu
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu, 210023, P. R. China
| | - Mengdi Wang
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu, 210023, P. R. China
| | - Shengchao Shi
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu, 210023, P. R. China
| | - Guodong Yuan
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu, 210023, P. R. China
| | - Xi Li
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu, 210023, P. R. China
| | - Hanchung Chong
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore, 637551, Singapore
- NTU Institute of Structural Biology, Nanyang Technological University, EMB 06-01, 59 Nanyang Drive, Singapore, 636921, Singapore
| | - Bin Wu
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore, 637551, Singapore
- NTU Institute of Structural Biology, Nanyang Technological University, EMB 06-01, 59 Nanyang Drive, Singapore, 636921, Singapore
| | - Peng Zheng
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu, 210023, P. R. China.
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45
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Measuring the average shape of transition paths during the folding of a single biological molecule. Proc Natl Acad Sci U S A 2019; 116:8125-8130. [PMID: 30952784 DOI: 10.1073/pnas.1816602116] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Transition paths represent the parts of a reaction where the energy barrier separating products and reactants is crossed. They are essential to understanding reaction mechanisms, yet many of their properties remain unstudied. Here, we report measurements of the average shape of transition paths, studying the folding of DNA hairpins as a model system for folding reactions. Individual transition paths were detected in the folding trajectories of hairpins with different sequences held under tension in optical tweezers, and path shapes were computed by averaging all transitions in the time domain, 〈t(x)〉, or by averaging transitions of a given duration in the extension domain, 〈x(t|τ)〉 τ Whereas 〈t(x)〉 was close to straight, with only a subtle curvature, 〈x(t|τ)〉 τ had more pronounced curvature that fit well to theoretical expectations for the dominant transition path, returning diffusion coefficients similar to values obtained previously from independent methods. Simulations suggested that 〈t(x)〉 provided a less reliable representation of the path shape than 〈x(t|τ)〉 τ , because it was far more sensitive to the effects of coupling the molecule to the experimental force probe. Intriguingly, the path shape variance was larger for some hairpins than others, indicating sequence-dependent changes in the diversity of transition paths reflective of differences in the character of the energy barriers, such as the width of the barrier saddle-point or the presence of parallel paths through multiple barriers between the folded and unfolded states. These studies of average path shapes point the way forward for probing the rich information contained in path shape fluctuations.
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46
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Kou L, Jin L, Lei H, Hu C, Li H, Hu X, Hu X. Real-time parallel 3D multiple particle tracking with single molecule centrifugal force microscopy. J Microsc 2018; 273:178-188. [PMID: 30489640 DOI: 10.1111/jmi.12773] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2018] [Revised: 11/16/2018] [Accepted: 11/20/2018] [Indexed: 12/20/2022]
Abstract
Real-time tracking of multiple particles is key for quantitative analysis of dynamic biophysical processes and materials science via time-lapse microscopy image data, especially for single molecule biophysical techniques, such as magnetic tweezers and centrifugal force microscopy. However, real-time multiple particle tracking with high resolution is limited by the current imaging processes or tracking algorithms. Here, we demonstrate 1 nm resolution in three dimensions in real-time with a graphics-processing unit (GPU) based on a compute unified device architecture (CUDA) parallel computing framework instead of only a central processing unit (CPU). We also explore the trade-offs between processing speed and size of the utilized regions of interest and a maximum speedup of 137 is achieved with the GPU compared with the CPU. Moreover, we utilize this method with our recently self-built centrifugal force microscope (CFM) in experiments that track multiple DNA-tethered particles. Our approach paves the way for high-throughput single molecule techniques with high resolution and efficiency. LAY DESCRIPTION: Particles are widely used as probes in life sciences through their motions. In single molecule techniques such as optical tweezers and magnetic tweezers, microbeads are used to study intermolecular or intramolecular interactions via beads tracking. Also tracking multiple beads' motions could study cell-cell or cell-ECM interactions in traction force microscopy. Therefore, particle tracking is of key important during these researches. However, parallel 3D multiple particle tracking in real-time with high resolution is a challenge either due to the algorithm or the program. Here, we combine the performance of CPU and CUDA-based GPU to make a hybrid implementation for particle tracking. In this way, a speedup of 137 is obtained compared the program before only with CPU without loss of accuracy. Moreover, we improve and build a new centrifugal force microscope for multiple single molecule force spectroscopy research in parallel. Then we employed our program into centrifugal force microscope for DNA stretching study. Our results not only demonstrate the application of this program in single molecule techniques, also indicate the capability of multiple single molecule study with centrifugal force microscopy.
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Affiliation(s)
- L Kou
- State Key Laboratory of Precision Measuring Technology and Instruments, Tianjin University, Tianjin, China
| | - L Jin
- State Key Laboratory of Precision Measuring Technology and Instruments, Tianjin University, Tianjin, China
| | - H Lei
- State Key Laboratory of Precision Measuring Technology and Instruments, Tianjin University, Tianjin, China
| | - C Hu
- State Key Laboratory of Precision Measuring Technology and Instruments, Tianjin University, Tianjin, China
| | - H Li
- State Key Laboratory of Precision Measuring Technology and Instruments, Tianjin University, Tianjin, China.,Department of Chemistry, University of British Columbia, Vancouver, BC, Canada
| | - X Hu
- State Key Laboratory of Precision Measuring Technology and Instruments, Tianjin University, Tianjin, China
| | - X Hu
- State Key Laboratory of Precision Measuring Technology and Instruments, Tianjin University, Tianjin, China
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47
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Pokrishevsky E, McAlary L, Farrawell NE, Zhao B, Sher M, Yerbury JJ, Cashman NR. Tryptophan 32-mediated SOD1 aggregation is attenuated by pyrimidine-like compounds in living cells. Sci Rep 2018; 8:15590. [PMID: 30349065 PMCID: PMC6197196 DOI: 10.1038/s41598-018-32835-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Accepted: 09/14/2018] [Indexed: 12/19/2022] Open
Abstract
Over 160 mutations in superoxide dismutase 1 (SOD1) are associated with familial amyotrophic lateral sclerosis (fALS), where the main pathological feature is deposition of SOD1 into proteinaceous cytoplasmic inclusions. We previously showed that the tryptophan residue at position 32 (W32) mediates the prion-like propagation of SOD1 misfolding in cells, and that a W32S substitution blocks this phenomenon. Here, we used in vitro protein assays to demonstrate that a W32S substitution in SOD1-fALS mutants significantly diminishes their propensity to aggregate whilst paradoxically decreasing protein stability. We also show SOD1-W32S to be resistant to seeded aggregation, despite its high abundance of unfolded protein. A cell-based aggregation assay demonstrates that W32S substitution significantly mitigates inclusion formation. Furthermore, this assay reveals that W32 in SOD1 is necessary for the formation of a competent seed for aggregation under these experimental conditions. Following the observed importance of W32 for aggregation, we established that treatment of living cells with the W32-interacting 5-Fluorouridine (5-FUrd), and its FDA approved analogue 5-Fluorouracil (5-FU), substantially attenuate inclusion formation similarly to W32S substitution. Altogether, we highlight W32 as a significant contributor to SOD1 aggregation, and propose that 5-FUrd and 5-FU present promising lead drug candidates for the treatment of SOD1-associated ALS.
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Affiliation(s)
- Edward Pokrishevsky
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, BC, V6T 2B5, Canada
| | - Luke McAlary
- Faculty of Science Medicine and Health, University of Wollongong, Wollongong, NSW, 2522, Australia.,Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, NSW, 2522, Australia
| | - Natalie E Farrawell
- Faculty of Science Medicine and Health, University of Wollongong, Wollongong, NSW, 2522, Australia.,Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, NSW, 2522, Australia
| | - Beibei Zhao
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, BC, V6T 2B5, Canada
| | - Mine Sher
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, BC, V6T 2B5, Canada
| | - Justin J Yerbury
- Faculty of Science Medicine and Health, University of Wollongong, Wollongong, NSW, 2522, Australia. .,Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, NSW, 2522, Australia.
| | - Neil R Cashman
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, BC, V6T 2B5, Canada.
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48
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Del Poggetto E, Toto A, Aloise C, Di Piro F, Gori L, Malatesta F, Gianni S, Chiti F, Bemporad F. Stability of an aggregation-prone partially folded state of human profilin-1 correlates with aggregation propensity. J Biol Chem 2018; 293:10303-10313. [PMID: 29760185 DOI: 10.1074/jbc.ra118.002087] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Revised: 05/02/2018] [Indexed: 12/11/2022] Open
Abstract
A set of missense mutations in the gene encoding profilin-1 has been linked to the onset of familial forms of ALS (fALS), also known as Lou Gehrig's disease. The pathogenic potential of these mutations is linked to the formation of intracellular inclusions of the mutant proteins and correlates with the mutation-induced destabilization of its native, fully folded state. However, the mechanism by which these mutations promote misfolding and self-assembly is yet unclear. Here, using temperature-jump and stopped-flow kinetic measurements, we show that, during refolding, WT profilin-1 transiently populates a partially folded (PF) state endowed with hydrophobic clusters exposed to the solvent and with no detectable secondary structure. We observed that this conformational state is marginally stable at neutral pH but becomes significantly populated at mildly acidic pH. Interestingly, the fALS-associated mutations did not cause a change in the refolding mechanism of profilin-1, but induced a stabilization of the PF state. In the presence of preformed profilin-1 aggregates, the PF state, unlike the unfolded and folded states, could interact with these aggregates via nonspecific hydrophobic interactions and also increase thioflavin-T fluorescence, revealing its amyloidogenic potential. Moreover, in the variants tested, we found a correlation between conformational stability of PF and aggregation propensity, defining this conformational state as an aggregation-prone folding intermediate. In conclusion, our findings indicate that mutation-induced stabilization of a partially folded state can enhance profilin-1 aggregation and thereby contribute to the pathogenicity of the mutations.
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Affiliation(s)
- Edoardo Del Poggetto
- From the Department of Experimental and Clinical Biomedical Sciences "Mario Serio," University of Florence, Viale G. B. Morgagni 50, 50134, Firenze, Italy
| | - Angelo Toto
- the Dipartimento di Scienze Biochimiche "A. Rossi Fanelli," Sapienza University of Rome, 00185 Rome, Italy, and
| | - Chiara Aloise
- From the Department of Experimental and Clinical Biomedical Sciences "Mario Serio," University of Florence, Viale G. B. Morgagni 50, 50134, Firenze, Italy
| | - Francesco Di Piro
- From the Department of Experimental and Clinical Biomedical Sciences "Mario Serio," University of Florence, Viale G. B. Morgagni 50, 50134, Firenze, Italy
| | - Ludovica Gori
- From the Department of Experimental and Clinical Biomedical Sciences "Mario Serio," University of Florence, Viale G. B. Morgagni 50, 50134, Firenze, Italy
| | - Francesco Malatesta
- the Dipartimento di Scienze Biochimiche "A. Rossi Fanelli," Sapienza University of Rome, 00185 Rome, Italy, and
| | - Stefano Gianni
- the Dipartimento di Scienze Biochimiche "A. Rossi Fanelli," Sapienza University of Rome, 00185 Rome, Italy, and.,the Istituto Pasteur-Fondazione Cenci Bolognetti and Istituto di Biologia e Patologia Molecolari del CNR, 00185 Rome, Italy
| | - Fabrizio Chiti
- From the Department of Experimental and Clinical Biomedical Sciences "Mario Serio," University of Florence, Viale G. B. Morgagni 50, 50134, Firenze, Italy
| | - Francesco Bemporad
- From the Department of Experimental and Clinical Biomedical Sciences "Mario Serio," University of Florence, Viale G. B. Morgagni 50, 50134, Firenze, Italy,
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