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Dürvanger Z, Bencs F, Menyhárd DK, Horváth D, Perczel A. Solvent induced amyloid polymorphism and the uncovering of the elusive class 3 amyloid topology. Commun Biol 2024; 7:968. [PMID: 39122990 PMCID: PMC11316126 DOI: 10.1038/s42003-024-06621-8] [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: 12/01/2023] [Accepted: 07/23/2024] [Indexed: 08/12/2024] Open
Abstract
Aggregation-prone-motifs (APRs) of proteins are short segments, which - as isolated peptides - form diverse amyloid-like crystals. We introduce two APRs - designed variants of the incretin mimetic Exendin-4 - that both display crystal-phase polymorphism. Crystallographic and spectroscopic analysis revealed that a single amino-acid substitution can greatly reduce topological variability: while LYIQWL can form both parallel and anti-parallel β-sheets, LYIQNL selects only the former. We also found that the parallel/anti-parallel switch of LYIQWL can be induced by simply changing the crystallization temperature. One crystal form of LYIQNL was found to belong to the class 3 topology, an arrangement previously not encountered among proteinogenic systems. We also show that subtle environmental changes lead to crystalline assemblies with different topologies, but similar interfaces. Spectroscopic measurements showed that polymorphism is already apparent in the solution state. Our results suggest that the temperature-, sequence- and environmental sensitivity of physiological amyloids is reflected in assemblies of the APR segments, which, complete with the new class 3 crystal form, effectively sample all the originally proposed basic topologies of amyloid-like aggregates.
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Affiliation(s)
- Zsolt Dürvanger
- Laboratory of Structural Chemistry and Biology, ELTE Eötvös Loránd University, Pázmány Péter sétány 1/A, H-1117, Budapest, Hungary
- HUN-REN-ELTE Protein Modeling Research Group, ELTE Eötvös Loránd University, Pázmány Péter sétány 1/A, H-1117, Budapest, Hungary
| | - Fruzsina Bencs
- Laboratory of Structural Chemistry and Biology, ELTE Eötvös Loránd University, Pázmány Péter sétány 1/A, H-1117, Budapest, Hungary
- Hevesy György PhD School of Chemistry, ELTE Eötvös Loránd University, Pázmány Péter sétány 1/A, H-1117, Budapest, Hungary
| | - Dóra K Menyhárd
- Laboratory of Structural Chemistry and Biology, ELTE Eötvös Loránd University, Pázmány Péter sétány 1/A, H-1117, Budapest, Hungary
- HUN-REN-ELTE Protein Modeling Research Group, ELTE Eötvös Loránd University, Pázmány Péter sétány 1/A, H-1117, Budapest, Hungary
| | - Dániel Horváth
- Laboratory of Structural Chemistry and Biology, ELTE Eötvös Loránd University, Pázmány Péter sétány 1/A, H-1117, Budapest, Hungary
- HUN-REN-ELTE Protein Modeling Research Group, ELTE Eötvös Loránd University, Pázmány Péter sétány 1/A, H-1117, Budapest, Hungary
| | - András Perczel
- Laboratory of Structural Chemistry and Biology, ELTE Eötvös Loránd University, Pázmány Péter sétány 1/A, H-1117, Budapest, Hungary.
- HUN-REN-ELTE Protein Modeling Research Group, ELTE Eötvös Loránd University, Pázmány Péter sétány 1/A, H-1117, Budapest, Hungary.
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2
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Mehra S, Bourkas ME, Kaczmarczyk L, Stuart E, Arshad H, Griffin JK, Frost KL, Walsh DJ, Supattapone S, Booth SA, Jackson WS, Watts JC. Convergent generation of atypical prions in knockin mouse models of genetic prion disease. J Clin Invest 2024; 134:e176344. [PMID: 39087478 PMCID: PMC11291267 DOI: 10.1172/jci176344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Accepted: 06/11/2024] [Indexed: 08/02/2024] Open
Abstract
Most cases of human prion disease arise due to spontaneous misfolding of WT or mutant prion protein, yet recapitulating this event in animal models has proven challenging. It remains unclear whether spontaneous prion generation can occur within the mouse lifespan in the absence of protein overexpression and how disease-causing mutations affect prion strain properties. To address these issues, we generated knockin mice that express the misfolding-prone bank vole prion protein (BVPrP). While mice expressing WT BVPrP (I109 variant) remained free from neurological disease, a subset of mice expressing BVPrP with mutations (D178N or E200K) causing genetic prion disease developed progressive neurological illness. Brains from spontaneously ill knockin mice contained prion disease-specific neuropathological changes as well as atypical protease-resistant BVPrP. Moreover, brain extracts from spontaneously ill D178N- or E200K-mutant BVPrP-knockin mice exhibited prion seeding activity and transmitted disease to mice expressing WT BVPrP. Surprisingly, the properties of the D178N- and E200K-mutant prions appeared identical before and after transmission, suggesting that both mutations guide the formation of a similar atypical prion strain. These findings imply that knockin mice expressing mutant BVPrP spontaneously develop a bona fide prion disease and that mutations causing prion diseases may share a uniform initial mechanism of action.
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Affiliation(s)
- Surabhi Mehra
- Tanz Centre for Research in Neurodegenerative Diseases and
| | - Matthew E.C. Bourkas
- Tanz Centre for Research in Neurodegenerative Diseases and
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | - Lech Kaczmarczyk
- Wallenberg Center for Molecular Medicine, Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Erica Stuart
- Tanz Centre for Research in Neurodegenerative Diseases and
| | - Hamza Arshad
- Tanz Centre for Research in Neurodegenerative Diseases and
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | | | - Kathy L. Frost
- One Health Division, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba, Canada
| | | | - Surachai Supattapone
- Department of Biochemistry and Cell Biology and
- Department of Medicine, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
| | - Stephanie A. Booth
- One Health Division, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba, Canada
- Department of Medical Microbiology and Infectious Diseases, Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Walker S. Jackson
- Wallenberg Center for Molecular Medicine, Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Joel C. Watts
- Tanz Centre for Research in Neurodegenerative Diseases and
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
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3
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Arshad H, Patel Z, Amano G, Li LY, Al-Azzawi ZAM, Supattapone S, Schmitt-Ulms G, Watts JC. A single protective polymorphism in the prion protein blocks cross-species prion replication in cultured cells. J Neurochem 2023; 165:230-245. [PMID: 36511154 DOI: 10.1111/jnc.15739] [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: 10/03/2022] [Revised: 11/22/2022] [Accepted: 11/28/2022] [Indexed: 12/14/2022]
Abstract
The bank vole (BV) prion protein (PrP) can function as a universal acceptor of prions. However, the molecular details of BVPrP's promiscuity for replicating a diverse range of prion strains remain obscure. To develop a cultured cell paradigm capable of interrogating the unique properties of BVPrP, we generated monoclonal lines of CAD5 cells lacking endogenous PrP but stably expressing either hamster (Ha), mouse (Mo), or BVPrP (M109 or I109 polymorphic variants) and then challenged them with various strains of mouse or hamster prions. Cells expressing BVPrP were susceptible to both mouse and hamster prions, whereas cells expressing MoPrP or HaPrP could only be infected with species-matched prions. Propagation of mouse and hamster prions in cells expressing BVPrP resulted in strain adaptation in several instances, as evidenced by alterations in conformational stability, glycosylation, susceptibility to anti-prion small molecules, and the inability of BVPrP-adapted mouse prion strains to infect cells expressing MoPrP. Interestingly, cells expressing BVPrP containing the G127V prion gene variant, identified in individuals resistant to kuru, were unable to become infected with prions. Moreover, the G127V polymorphic variant impeded the spontaneous aggregation of recombinant BVPrP. These results demonstrate that BVPrP can facilitate cross-species prion replication in cultured cells and that a single amino acid change can override the prion-permissive nature of BVPrP. This cellular paradigm will be useful for dissecting the molecular features of BVPrP that allow it to function as a universal prion acceptor.
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Affiliation(s)
- Hamza Arshad
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario, Canada
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | - Zeel Patel
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario, Canada
| | - Genki Amano
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario, Canada
| | - Le Yao Li
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario, Canada
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | - Zaid A M Al-Azzawi
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario, Canada
| | - Surachai Supattapone
- Department of Biochemistry, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
- Department of Medicine, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
| | - Gerold Schmitt-Ulms
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Joel C Watts
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario, Canada
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
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4
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Vanni I, Iacobone F, D’Agostino C, Giovannelli M, Pirisinu L, Altmeppen HC, Castilla J, Torres JM, Agrimi U, Nonno R. An optimized Western blot assay provides a comprehensive assessment of the physiological endoproteolytic processing of the prion protein. J Biol Chem 2022; 299:102823. [PMID: 36565989 PMCID: PMC9867980 DOI: 10.1016/j.jbc.2022.102823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Revised: 12/06/2022] [Accepted: 12/10/2022] [Indexed: 12/24/2022] Open
Abstract
The prion protein (PrPC) is subjected to several conserved endoproteolytic events producing bioactive fragments that are of increasing interest for their physiological functions and their implication in the pathogenesis of prion diseases and other neurodegenerative diseases. However, systematic and comprehensive investigations on the full spectrum of PrPC proteoforms have been hampered by the lack of methods able to identify all PrPC-derived proteoforms. Building on previous knowledge of PrPC endoproteolytic processing, we thus developed an optimized Western blot assay able to obtain the maximum information about PrPC constitutive processing and the relative abundance of PrPC proteoforms in a complex biological sample. This approach led to the concurrent identification of the whole spectrum of known endoproteolytic-derived PrPC proteoforms in brain homogenates, including C-terminal, N-terminal and, most importantly, shed PrPC-derived fragments. Endoproteolytic processing of PrPC was remarkably similar in the brain of widely used wild type and transgenic rodent models, with α-cleavage-derived C1 representing the most abundant proteoform and ADAM10-mediated shedding being an unexpectedly prominent proteolytic event. Interestingly, the relative amount of shed PrPC was higher in WT mice than in most other models. Our results indicate that constitutive endoproteolytic processing of PrPC is not affected by PrPC overexpression or host factors other than PrPC but can be impacted by PrPC primary structure. Finally, this method represents a crucial step in gaining insight into pathophysiological roles, biomarker suitability, and therapeutic potential of shed PrPC and for a comprehensive appraisal of PrPC proteoforms in therapies, drug screening, or in the progression of neurodegenerative diseases.
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Affiliation(s)
- Ilaria Vanni
- Department of Food Safety, Nutrition and Veterinary Public Health, Istituto Superiore di Sanità, Rome, Italy.
| | - Floriana Iacobone
- Department of Food Safety, Nutrition and Veterinary Public Health, Istituto Superiore di Sanità, Rome, Italy
| | - Claudia D’Agostino
- Department of Food Safety, Nutrition and Veterinary Public Health, Istituto Superiore di Sanità, Rome, Italy
| | - Matteo Giovannelli
- Department of Food Safety, Nutrition and Veterinary Public Health, Istituto Superiore di Sanità, Rome, Italy
| | - Laura Pirisinu
- Department of Food Safety, Nutrition and Veterinary Public Health, Istituto Superiore di Sanità, Rome, Italy
| | | | - Joaquin Castilla
- Basque Research and Technology Alliance (BRTA) - CIC BioGUNE & IKERBasque, Bizkaia, Spain,Centro de Investigación Biomédica en Red de Enfermedades infecciosas (CIBERINFEC), Instituto de Salud Carlos III, Madrid, Spain
| | - Juan Maria Torres
- Centro de Investigación en Sanidad Animal (CISA-INIA-CSIC), Valdeolmos, Madrid, Spain
| | - Umberto Agrimi
- Department of Food Safety, Nutrition and Veterinary Public Health, Istituto Superiore di Sanità, Rome, Italy
| | - Romolo Nonno
- Department of Food Safety, Nutrition and Veterinary Public Health, Istituto Superiore di Sanità, Rome, Italy
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5
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Bowler JT, Sawaya MR, Boyer DR, Cascio D, Bali M, Eisenberg DS. Micro-electron diffraction structure of the aggregation-driving N-terminus of Drosophila neuronal protein Orb2A reveals amyloid-like β-sheets. J Biol Chem 2022; 298:102396. [PMID: 35988647 PMCID: PMC9556795 DOI: 10.1016/j.jbc.2022.102396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 08/11/2022] [Accepted: 08/12/2022] [Indexed: 11/26/2022] Open
Abstract
Amyloid protein aggregation is commonly associated with progressive neurodegenerative diseases, however not all amyloid fibrils are pathogenic. The neuronal cytoplasmic polyadenylation element binding (CPEB) protein is a regulator of synaptic mRNA translation, and has been shown to form functional amyloid aggregates that stabilize long-term memory. In adult Drosophila neurons, the CPEB homolog Orb2 is expressed as two isoforms, of which the Orb2B isoform is far more abundant, but the rarer Orb2A isoform is required to initiate Orb2 aggregation. The N-terminus is a distinctive feature of the Orb2A isoform and is critical for its aggregation. Intriguingly, replacement of phenylalanine in the 5th position of Orb2A with tyrosine (F5Y) in Drosophila impairs stabilization of long-term memory. The structure of endogenous Orb2B fibers was recently determined by cryo-EM, but the structure adopted by fibrillar Orb2A is less certain. Here we use micro-electron diffraction to determine the structure of the first nine N-terminal residues of Orb2A, at a resolution of 1.05 Å. We find that this segment (which we term M9I) forms an amyloid-like array of parallel in-register β-sheets, which interact through side chain interdigitation of aromatic and hydrophobic residues. Our structure provides an explanation for the decreased aggregation observed for the F5Y mutant, and offers a hypothesis for how the addition of a single atom (the tyrosyl oxygen) affects long-term memory. We also propose a structural model of Orb2A that integrates our structure of the M9I segment with the published Orb2B cryo-EM structure.
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Affiliation(s)
- Jeannette T Bowler
- Molecular Biology Institute, University of California, Los Angeles; Howard Hughes Medical Institute.
| | - Michael R Sawaya
- Molecular Biology Institute, University of California, Los Angeles; Howard Hughes Medical Institute
| | - David R Boyer
- Molecular Biology Institute, University of California, Los Angeles; Howard Hughes Medical Institute
| | - Duilio Cascio
- Molecular Biology Institute, University of California, Los Angeles; Howard Hughes Medical Institute
| | - Manya Bali
- Molecular Biology Institute, University of California, Los Angeles; Howard Hughes Medical Institute
| | - David S Eisenberg
- Molecular Biology Institute, University of California, Los Angeles; Howard Hughes Medical Institute.
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6
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Foley AR, Raskatov JA. Understanding and controlling amyloid aggregation with chirality. Curr Opin Chem Biol 2021; 64:1-9. [PMID: 33610939 PMCID: PMC8368077 DOI: 10.1016/j.cbpa.2021.01.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Revised: 01/11/2021] [Accepted: 01/16/2021] [Indexed: 12/22/2022]
Abstract
Amyloid aggregation and human disease are inextricably linked. Examples include Alzheimer disease, Parkinson disease, and type II diabetes. While seminal advances on the mechanistic understanding of these diseases have been made over the last decades, controlling amyloid fibril formation still represents a challenge, and it is a subject of active research. In this regard, chiral modifications have increasingly been proved to offer a particularly well-suited approach toward accessing to previously unknown aggregation pathways and to provide with novel insights on the biological mechanisms of action of amyloidogenic peptides and proteins. Here, we summarize recent advances on how the use of mirror-image peptides/proteins and d-amino acid incorporations have helped modulate amyloid aggregation, offered new mechanistic tools to study cellular interactions, and allowed us to identify key positions within the peptide/protein sequence that influence amyloid fibril growth and toxicity.
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Affiliation(s)
- Alejandro R Foley
- Department of Chemistry and Biochemistry, University of California Santa Cruz, Santa Cruz, CA, 95064, USA
| | - Jevgenij A Raskatov
- Department of Chemistry and Biochemistry, University of California Santa Cruz, Santa Cruz, CA, 95064, USA.
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7
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Wang F, Gnewou O, Modlin C, Beltran LC, Xu C, Su Z, Juneja P, Grigoryan G, Egelman EH, Conticello VP. Structural analysis of cross α-helical nanotubes provides insight into the designability of filamentous peptide nanomaterials. Nat Commun 2021; 12:407. [PMID: 33462223 PMCID: PMC7814010 DOI: 10.1038/s41467-020-20689-w] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Accepted: 12/02/2020] [Indexed: 12/12/2022] Open
Abstract
The exquisite structure-function correlations observed in filamentous protein assemblies provide a paradigm for the design of synthetic peptide-based nanomaterials. However, the plasticity of quaternary structure in sequence-space and the lability of helical symmetry present significant challenges to the de novo design and structural analysis of such filaments. Here, we describe a rational approach to design self-assembling peptide nanotubes based on controlling lateral interactions between protofilaments having an unusual cross-α supramolecular architecture. Near-atomic resolution cryo-EM structural analysis of seven designed nanotubes provides insight into the designability of interfaces within these synthetic peptide assemblies and identifies a non-native structural interaction based on a pair of arginine residues. This arginine clasp motif can robustly mediate cohesive interactions between protofilaments within the cross-α nanotubes. The structure of the resultant assemblies can be controlled through the sequence and length of the peptide subunits, which generates synthetic peptide filaments of similar dimensions to flagella and pili.
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Affiliation(s)
- Fengbin Wang
- Department of Biochemistry and Molecular Genetics, University of Virginia, Charlottesville, VA, 22908, USA
| | - Ordy Gnewou
- Department of Chemistry, Emory University, Atlanta, GA, 30322, USA
| | - Charles Modlin
- Department of Chemistry, Emory University, Atlanta, GA, 30322, USA
| | - Leticia C Beltran
- Department of Biochemistry and Molecular Genetics, University of Virginia, Charlottesville, VA, 22908, USA
| | - Chunfu Xu
- Department of Chemistry, Emory University, Atlanta, GA, 30322, USA
| | - Zhangli Su
- Department of Biochemistry and Molecular Genetics, University of Virginia, Charlottesville, VA, 22908, USA
| | - Puneet Juneja
- The Robert P. Apkarian Integrated Electron Microscopy Core (IEMC), Emory University, Atlanta, GA, 30322, USA
| | - Gevorg Grigoryan
- Department of Computer Science, Dartmouth College, Hanover, NH, 03755, USA.,Department of Biological Sciences, Dartmouth College, Hanover, NH, 03755, USA
| | - Edward H Egelman
- Department of Biochemistry and Molecular Genetics, University of Virginia, Charlottesville, VA, 22908, USA
| | - Vincent P Conticello
- Department of Chemistry, Emory University, Atlanta, GA, 30322, USA. .,The Robert P. Apkarian Integrated Electron Microscopy Core (IEMC), Emory University, Atlanta, GA, 30322, USA.
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8
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Suzuki A, Sawada K, Yamasaki T, Denkers ND, Mathiason CK, Hoover EA, Horiuchi M. Involvement of N- and C-terminal region of recombinant cervid prion protein in its reactivity to CWD and atypical BSE prions in real-time quaking-induced conversion reaction in the presence of high concentrations of tissue homogenates. Prion 2020; 14:283-295. [PMID: 33345717 PMCID: PMC7757825 DOI: 10.1080/19336896.2020.1858694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 11/25/2020] [Accepted: 11/25/2020] [Indexed: 11/17/2022] Open
Abstract
The real-time quaking-induced conversion (RT-QuIC) reaction is a sensitive and specific method for detecting prions. However, inhibitory factors present in tissue homogenates can easily interfere with this reaction. To identify the RT-QuIC condition under which low levels of chronic wasting disease (CWD) and bovine spongiform encephalopathy (BSE) prions can be detected in the presence of high concentrations of brain tissue homogenates, reactivities of various recombinant prion proteins (rPrPs) were tested. Among the tested rPrPs, recombinant cervid PrP (rCerPrP) showed a unique reactivity: the reactivity of rCerPrP to CWD and atypical BSE prions was not highly affected by high concentrations of normal brain homogenates. The unique reactivity of rCerPrP disappeared when the N-terminal region (aa 25-93) was truncated. Replacement of aa 23-149 of mouse (Mo) PrP with the corresponding region of CerPrP partially restored the unique reactivity of rCerPrP in RT-QuIC. Replacement of the extreme C-terminal region of MoPrP aa 219-231 to the corresponding region of CerPrP partially conferred the unique reactivity of rCerPrP to rMoPrP, suggesting the involvement of both N- and C-terminal regions. Additionally, rCerN-Mo-CerCPrP, a chimeric PrP comprising CerPrP aa 25-153, MoPrP aa 150-218, and CerPrP aa 223-233, showed an additive effect of the N- and C-terminal regions. These results provide a mechanistic implication for detecting CWD and atypical BSE prions using rCerPrP and are useful for further improvements of RT-QuIC.
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Affiliation(s)
- Akio Suzuki
- Laboratory of Veterinary Hygiene, Graduate School of Infectious Diseases, Hokkaido University, Kita-ku, Sapporo, Japan
| | - Kazuhei Sawada
- Laboratory of Veterinary Hygiene, Graduate School of Infectious Diseases, Hokkaido University, Kita-ku, Sapporo, Japan
| | - Takeshi Yamasaki
- Laboratory of Veterinary Hygiene, Graduate School of Infectious Diseases, Hokkaido University, Kita-ku, Sapporo, Japan
| | - Nathaniel D Denkers
- Prion Research Center, Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA
| | - Candace K Mathiason
- Prion Research Center, Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA
| | - Edward A Hoover
- Prion Research Center, Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA
| | - Motohiro Horiuchi
- Laboratory of Veterinary Hygiene, Graduate School of Infectious Diseases, Hokkaido University, Kita-ku, Sapporo, Japan
- Global Station for Zoonosis Control. Global Institute for Collaborative Research and Education, Hokkaido University, Kita-ku, Sapporo, Japan
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9
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Wiegand T, Malär AA, Cadalbert R, Ernst M, Böckmann A, Meier BH. Asparagine and Glutamine Side-Chains and Ladders in HET-s(218-289) Amyloid Fibrils Studied by Fast Magic-Angle Spinning NMR. Front Mol Biosci 2020; 7:582033. [PMID: 33195425 PMCID: PMC7556116 DOI: 10.3389/fmolb.2020.582033] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Accepted: 08/28/2020] [Indexed: 12/11/2022] Open
Abstract
Asparagine and glutamine side-chains can form hydrogen-bonded ladders which contribute significantly to the stability of amyloid fibrils. We show, using the example of HET-s(218–289) fibrils, that the primary amide side-chain proton resonances can be detected in cross-polarization based solid-state NMR spectra at fast magic-angle spinning (MAS). J-coupling based experiments offer the possibility to distinguish them from backbone amide groups if the spin-echo lifetimes are long enough, which turned out to be the case for the glutamine side-chains, but not for the asparagine side-chains forming asparagine ladders. We explore the sensitivity of NMR observables to asparagine ladder formation. One of the two possible asparagine ladders in HET-s(218–289), the one comprising N226 and N262, is assigned by proton-detected 3D experiments at fast MAS and significant de-shielding of one of the NH2 proton resonances indicative of hydrogen-bond formation is observed. Small rotating-frame 15N relaxation-rate constants point to rigidified asparagine side-chains in this ladder. The proton resonances are homogeneously broadened which could indicate chemical exchange, but is presently not fully understood. The second asparagine ladder (N243 and N279) in contrast remains more flexible.
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Affiliation(s)
- Thomas Wiegand
- Physical Chemistry, Eidgenössische Technische Hochschule (ETH) Zurich, Zurich, Switzerland
| | - Alexander A Malär
- Physical Chemistry, Eidgenössische Technische Hochschule (ETH) Zurich, Zurich, Switzerland
| | - Riccardo Cadalbert
- Physical Chemistry, Eidgenössische Technische Hochschule (ETH) Zurich, Zurich, Switzerland
| | - Matthias Ernst
- Physical Chemistry, Eidgenössische Technische Hochschule (ETH) Zurich, Zurich, Switzerland
| | - Anja Böckmann
- Molecular Microbiology and Structural Biochemistry, UMR 5086 CNRS/Université de Lyon, Labex Ecofect, Lyon, France
| | - Beat H Meier
- Physical Chemistry, Eidgenössische Technische Hochschule (ETH) Zurich, Zurich, Switzerland
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10
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Arshad H, Bourkas MEC, Watts JC. The utility of bank voles for studying prion disease. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2020; 175:179-211. [PMID: 32958232 DOI: 10.1016/bs.pmbts.2020.08.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The transmission of prions between species is typically an inefficient process due to the species barrier, which represents incompatibility between prion seed and substrate molecules. Bank voles (Myodes glareolus) are an exception to this rule, as they are susceptible to a diverse range of prion strains from many different animal species. In particular, bank voles can be efficiently infected with most types of human prions and have played a critical role in validating variably protease-sensitive prionopathy (VPSPr) and certain forms of Gerstmann-Sträussler-Scheinker (GSS) disease as bona fide prion disorders rather than non-transmissible proteinopathies. The bank vole prion protein (BVPrP) confers a "universal prion acceptor" phenotype when expressed in mice and when used as a substrate for in vitro prion amplification assays, indicating that the unique prion transmission properties of bank voles are mediated by BVPrP. Over-expression of BVPrP in mice can also promote the spontaneous development of prion disease, indicating that BVPrP is intrinsically prone to both spontaneous and template-directed misfolding. Here, we discuss the utility of bank voles and BVPrP for prion research and how they have provided new tools for establishing rapid animal bioassays, modeling spontaneous prion disease, standardizing prion diagnostics, and understanding the molecular basis of the species barrier.
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Affiliation(s)
- Hamza Arshad
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, ON, Canada; Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Matthew E C Bourkas
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, ON, Canada; Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Joel C Watts
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, ON, Canada; Department of Biochemistry, University of Toronto, Toronto, ON, Canada.
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11
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Identification of a homology-independent linchpin domain controlling mouse and bank vole prion protein conversion. PLoS Pathog 2020; 16:e1008875. [PMID: 32898162 PMCID: PMC7508373 DOI: 10.1371/journal.ppat.1008875] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Revised: 09/22/2020] [Accepted: 08/11/2020] [Indexed: 11/19/2022] Open
Abstract
Prions are unorthodox pathogens that cause fatal neurodegenerative diseases in humans and other mammals. Prion propagation occurs through the self-templating of the pathogenic conformer PrPSc, onto the cell-expressed conformer, PrPC. Here we study the conversion of PrPC to PrPSc using a recombinant mouse PrPSc conformer (mouse protein-only recPrPSc) as a unique tool that can convert bank vole but not mouse PrPC substrates in vitro. Thus, its templating ability is not dependent on sequence homology with the substrate. In the present study, we used chimeric bank vole/mouse PrPC substrates to systematically determine the domain that allows for conversion by Mo protein-only recPrPSc. Our results show that that either the presence of the bank vole amino acid residues E227 and S230 or the absence of the second N-linked glycan are sufficient to allow PrPC substrates to be converted by Mo protein-only recPrPSc and several native infectious prion strains. We propose that residues 227 and 230 and the second glycan are part of a C-terminal domain that acts as a linchpin for bank vole and mouse prion conversion. Prions are unconventional infectious agents that lack nucleic acids such as DNA and RNA, and the mechanism by which prions replicate is not fully understood. It has been established that a central feature of the replication mechanism involves the misfolding of a host protein (PrPC) into an infectious shape termed PrPSc, but it is unclear how this misfolding occurs. Interestingly, it has been observed that a particular animal species, the European bank vole, is unusually susceptible to prion infection and that this near-universal susceptibility is caused by the specific PrPC sequence of this protein. Here we use a powerful and unique biochemical system to determine the specific region of bank vole PrPC that is primarily responsible for its propensity to misfold into PrPSc. This critical region, which is located at the extreme C-terminal end of the protein, appears to act as a linchpin domain that normally stabilizes the shape of PrPC and thereby regulates its misfolding into PrPSc.
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12
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Slapšak U, Salzano G, Ilc G, Giachin G, Bian J, Telling G, Legname G, Plavec J. Unique Structural Features of Mule Deer Prion Protein Provide Insights into Chronic Wasting Disease. ACS OMEGA 2019; 4:19913-19924. [PMID: 31788624 PMCID: PMC6882122 DOI: 10.1021/acsomega.9b02824] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/01/2019] [Accepted: 11/06/2019] [Indexed: 06/10/2023]
Abstract
Chronic wasting disease (CWD) is a highly infectious prion disease of cervids. Accumulation of prions, the disease-specific structural conformers of the cellular prion protein (PrPC), in the central nervous system, is the key pathological event of the disorder. The analysis of cervid PrPC sequences revealed the existence of polymorphism at position 226, in which deer PrP contains glutamine (Q), whereas elk PrP contains glutamate (E). The effects of this polymorphism on CWD are still unknown. We determined the high-resolution nuclear magnetic resonance structure of the mule deer prion protein that was compared to previously published PrP structures of elk and white-tailed deer. We found that the polymorphism Q226E could influence the long-range intramolecular interactions and packing of the β2-α2 loop and the C-terminus of the α3 helix of cervid PrP structures. This solvent-accessible epitope is believed to be involved in prion conversion. Additional differences were observed at the beginning of the well-defined C-terminus domain, in the α2-α3 region, and in its interactions with the α1 helix. Here, we highlight the importance of the PrP structure in prion susceptibility and how single amino acid differences might influence the overall protein folding.
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Affiliation(s)
- Urška Slapšak
- Slovenian NMR Centre, National Institute of Chemistry, SI-1000 Ljubljana, Ljubljana, Slovenia
| | - Giulia Salzano
- Laboratory of Prion Biology, Department
of Neuroscience, Scuola Internazionale Superiore
di Studi Avanzati (SISSA), Via Bonomea 265, I-34136 Trieste, Trieste, Italy
| | - Gregor Ilc
- Slovenian NMR Centre, National Institute of Chemistry, SI-1000 Ljubljana, Ljubljana, Slovenia
- EN-FIST Centre of Excellence, SI-1000 Ljubljana, Ljubljana, Slovenia
| | - Gabriele Giachin
- Laboratory of Prion Biology, Department
of Neuroscience, Scuola Internazionale Superiore
di Studi Avanzati (SISSA), Via Bonomea 265, I-34136 Trieste, Trieste, Italy
- Structural
Biology Group, European Synchrotron Radiation
Facility (ESRF), 38000 Grenoble, Auvergne-Rhône-Alpes, France
| | - Jifeng Bian
- Prion Research Center (PRC) and Department of Microbiology,
Immunology and Pathology, Colorado State
University, Fort Collins, Colorado 80525, United States
| | - Glenn Telling
- Prion Research Center (PRC) and Department of Microbiology,
Immunology and Pathology, Colorado State
University, Fort Collins, Colorado 80525, United States
| | - Giuseppe Legname
- Laboratory of Prion Biology, Department
of Neuroscience, Scuola Internazionale Superiore
di Studi Avanzati (SISSA), Via Bonomea 265, I-34136 Trieste, Trieste, Italy
- ELETTRA-Sincrotrone Trieste S.C.p.A, 34149 Trieste, Friuli Venezia Giulia, Italy
| | - Janez Plavec
- Slovenian NMR Centre, National Institute of Chemistry, SI-1000 Ljubljana, Ljubljana, Slovenia
- EN-FIST Centre of Excellence, SI-1000 Ljubljana, Ljubljana, Slovenia
- Department of Chemistry and Biochemistry, Faculty of Chemistry and
Chemical Technology, University of Ljubljana, SI-1000 Ljubljana, Ljubljana, Slovenia
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13
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Ma T, Deng J, Ma S, Zhao W, Chang Z, Yu K, Yang J. Structural Mechanism of Barriers to Interspecies Seeding Transmissibility of Full-Length Prion Protein Amyloid. Chembiochem 2019; 20:2757-2766. [PMID: 31161647 DOI: 10.1002/cbic.201900218] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Indexed: 12/13/2022]
Abstract
A puzzling feature of prion diseases is the cross-species barriers. The detailed molecular mechanisms underlying these interspecies barriers remain poorly understood because of a lack of high-resolution structural information on the scrapie isoform of the prion protein (PrPSc ). In this study we identified the critical role of the residues 165/167 in the barrier to seeding mouse PrP (mPrP) fibril seeds to human cellular prion protein (PrPC ). Solid-state NMR revealed a C-terminal β-sheet core spanning residues 165-230 and the packing arrangement of mPrP fibrils. Residues 165/167 are located on one end of the fibril core. Molecular dynamics simulations demonstrated that the stabilities of the seeding-induced β-strand structures are significantly impacted by hydrogen bonds involving the side chain of residue 167 and steric resistance involving residue 165. These findings suggest that the α2-β2 loop containing residues 165/167 could be the initial site of seed-template conformational conversion.
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Affiliation(s)
- Tao Ma
- National Center for Magnetic Resonance in Wuhan, Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and, Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, 430071, P. R. China.,University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Jing Deng
- National Center for Magnetic Resonance in Wuhan, Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and, Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, 430071, P. R. China.,University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Shaojie Ma
- National Center for Magnetic Resonance in Wuhan, Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and, Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, 430071, P. R. China.,College of Life Science & Technology, Huazhong University of Science and Technology, Wuhan, 430071, P. R. China
| | - Weijing Zhao
- National Center for Magnetic Resonance in Wuhan, Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and, Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, 430071, P. R. China
| | - Ziwei Chang
- National Center for Magnetic Resonance in Wuhan, Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and, Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, 430071, P. R. China
| | - Kunqian Yu
- Drug Discovery and Design Center, CAS Key Laboratory of Receptor Research, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, P. R. China.,University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Jun Yang
- National Center for Magnetic Resonance in Wuhan, Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and, Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, 430071, P. R. China.,College of Life Science & Technology, Huazhong University of Science and Technology, Wuhan, 430071, P. R. China
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14
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Foley AR, Finn TS, Kung T, Hatami A, Lee HW, Jia M, Rolandi M, Raskatov JA. Trapping and Characterization of Nontoxic Aβ42 Aggregation Intermediates. ACS Chem Neurosci 2019; 10:3880-3887. [PMID: 31319029 DOI: 10.1021/acschemneuro.9b00340] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Amyloid β (Aβ) 42 is an aggregation-prone peptide and the believed seminal etiological agent of Alzheimer's disease (AD). Intermediates of Aβ42 aggregation, commonly referred to as diffusible oligomers, are considered to be among the most toxic forms of the peptide. Here, we studied the effect of the age-related epimerization of Ser26 (i.e., S26s chiral edit) in Aβ42 and discovered that this subtle molecular change led to reduced fibril formation propensity. Surprisingly, the resultant soluble aggregates were nontoxic. To gain insight into the structural changes that occurred in the peptide upon S26s substitution, the system was probed using an array of biophysical and biochemical methods. These experiments consistently pointed to the stabilization of aggregation intermediates in the Aβ42-S26s system. To better understand the changes arising as a consequence of the S26s substitution, molecular level structural studies were performed. Using a combined nuclear magnetic resonance (NMR)- and density functional theory (DFT)-computational approach, we found that the S26s chiral edit induced only local structural changes in the Gly25-Ser26-Asn27 region. Interestingly, these subtle changes enabled the formation of an intramolecular Ser26-Asn27 H-bond, which disrupted the ability of Asn27 to engage in the fibrillogenic side chain-to-side chain H-bonding pattern. This reveals that intermolecular stabilizing interactions between Asn27 side chains are a key element controlling Aβ42 aggregation and toxicity.
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Affiliation(s)
- Alejandro R. Foley
- Department of Chemistry and Biochemistry, University of California Santa Cruz, Santa Cruz, California 95064, United States
| | - Thomas S. Finn
- Department of Chemistry and Biochemistry, University of California Santa Cruz, Santa Cruz, California 95064, United States
| | - Timothy Kung
- Department of Chemistry and Biochemistry, University of California Santa Cruz, Santa Cruz, California 95064, United States
| | - Asa Hatami
- Sangamo Therapeutics, Richmond, California 94804, United States
| | - Hsiau-Wei Lee
- Department of Chemistry and Biochemistry, University of California Santa Cruz, Santa Cruz, California 95064, United States
| | - Manping Jia
- Department of Electrical Engineering, University of California Santa Cruz, Santa Cruz, California 95064, United States
| | - Marco Rolandi
- Department of Electrical Engineering, University of California Santa Cruz, Santa Cruz, California 95064, United States
| | - Jevgenij A. Raskatov
- Department of Chemistry and Biochemistry, University of California Santa Cruz, Santa Cruz, California 95064, United States
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15
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Wu H, Saltzberg DJ, Kratochvil HT, Jo H, Sali A, DeGrado WF. Glutamine Side Chain 13C═ 18O as a Nonperturbative IR Probe of Amyloid Fibril Hydration and Assembly. J Am Chem Soc 2019; 141:7320-7326. [PMID: 30998340 DOI: 10.1021/jacs.9b00577] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Infrared (IR) spectroscopy has provided considerable insight into the structures, dynamics, and formation mechanisms of amyloid fibrils. IR probes, such as main chain 13C═18O, have been widely employed to obtain site-specific structural information, yet only secondary structures and strand-to-strand arrangements can be probed. Very few nonperturbative IR probes are available to report on the side-chain conformation and environments, which are critical to determining sheet-to-sheet arrangements in steric zippers within amyloids. Polar residues, such as glutamine, contribute significantly to the stability of amyloids and thus are frequently found in core regions of amyloid peptides/proteins. Furthermore, polyglutamine (polyQ) repeats form toxic aggregates in several neurodegenerative diseases. Here we report the synthesis and application of a new nonperturbative IR probe-glutamine side chain 13C═18O. We use side chain 13C═18O labeling and isotope dilution to detect the presence of intermolecularly hydrogen-bonded arrays of glutamine side chains (Gln ladders) in amyloid-forming peptides. Moreover, the line width of the 13C═18O peak is highly sensitive to its local hydration environment. The IR data from side chain labeling allows us to unambiguously determine the sheet-to-sheet arrangement in a short amyloid-forming peptide, GNNQQNY, providing insight that was otherwise inaccessible through main chain labeling. With several different fibril samples, we also show the versatility of this IR probe in studying the structures and aggregation kinetics of amyloids. Finally, we demonstrate the capability of modeling amyloid structures with IR data using the integrative modeling platform (IMP) and the potential of integrating IR with other biophysical methods for more accurate structural modeling. Together, we believe that side chain 13C═18O will complement main chain isotope labeling in future IR studies of amyloids and integrative modeling using IR data will significantly expand the power of IR spectroscopy to elucidate amyloid assemblies.
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16
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Blodgett KN, Fischer JL, Lee J, Choi SH, Zwier TS. Conformation-Specific Spectroscopy of Asparagine-Containing Peptides: Influence of Single and Adjacent Asn Residues on Inherent Conformational Preferences. J Phys Chem A 2018; 122:8762-8775. [PMID: 30343572 DOI: 10.1021/acs.jpca.8b08418] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Karl N. Blodgett
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907-2084, United States
| | - Joshua L. Fischer
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907-2084, United States
| | - Jaeyeon Lee
- Department of Chemistry, Yonsei University, Seoul 03722, Korea
| | - Soo Hyuk Choi
- Department of Chemistry, Yonsei University, Seoul 03722, Korea
| | - Timothy S. Zwier
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907-2084, United States
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17
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Sub-ångström cryo-EM structure of a prion protofibril reveals a polar clasp. Nat Struct Mol Biol 2018; 25:131-134. [PMID: 29335561 PMCID: PMC6170007 DOI: 10.1038/s41594-017-0018-0] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Accepted: 12/07/2017] [Indexed: 11/18/2022]
Abstract
The atomic structure of the infectious, protease-resistant, β-sheet-rich and fibrillar mammalian prion remains unknown. Through the cryo-EM method, MicroED, we reveal the sub-1Å resolution structure of a protofibril formed by a wild-type segment from the β2-α2 loop of the bank vole prion protein. The structure of this protofibril reveals a stabilizing network of hydrogen bonds that link polar zippers within a sheet, producing motifs we name ‘polar clasps’. Ultrahigh-resolution cryo-EM structure reveals a prion protofibril stabilized by a dense three-dimensional network of hydrogen bonds.
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