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Chang SC, Hannaoui S, Arifin MI, Huang YH, Tang X, Wille H, Gilch S. Propagation of PrP Sc in mice reveals impact of aggregate composition on prion disease pathogenesis. Commun Biol 2023; 6:1162. [PMID: 37964018 PMCID: PMC10645910 DOI: 10.1038/s42003-023-05541-3] [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: 10/10/2022] [Accepted: 11/03/2023] [Indexed: 11/16/2023] Open
Abstract
Infectious prions consist of PrPSc, a misfolded, aggregation-prone isoform of the host's prion protein. PrPSc assemblies encode distinct biochemical and biological properties. They harbor a specific profile of PrPSc species, from small oligomers to fibrils in different ratios, where the highest infectivity aligns with oligomeric particles. To investigate the impact of PrPSc aggregate complexity on prion propagation, biochemical properties, and disease pathogenesis, we fractionated elk prions by sedimentation velocity centrifugation, followed by sub-passages of individual fractions in cervidized mice. Upon first passage, different fractions generated PrPSc with distinct biochemical, biophysical, and neuropathological profiles. Notably, low or high molecular weight PrPSc aggregates caused different clinical signs of hyperexcitability or lethargy, respectively, which were retained over passage, whereas other properties converged. Our findings suggest that PrPSc quaternary structure determines an initial selection of a specific replication environment, resulting in transmissible features that are independent of PrPSc biochemical and biophysical properties.
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Affiliation(s)
- Sheng Chun Chang
- Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
- Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Samia Hannaoui
- Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
- Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Maria Immaculata Arifin
- Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
- Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Yuan-Hung Huang
- Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
- Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Xinli Tang
- Department of Biochemistry, Center for Prions and Protein Folding Diseases, University of Alberta, Edmonton, AB, Canada
| | - Holger Wille
- Department of Biochemistry, Center for Prions and Protein Folding Diseases, University of Alberta, Edmonton, AB, Canada
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, Canada
| | - Sabine Gilch
- Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada.
- Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.
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2
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Secker TJ, Hervé RC, Keevil CW. Sensitive microscopic quantification of surface-bound prion infectivity for the assessment of surgical instrument decontamination procedures. J Hosp Infect 2023; 132:116-124. [PMID: 36209927 DOI: 10.1016/j.jhin.2022.09.020] [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: 08/05/2022] [Revised: 09/07/2022] [Accepted: 09/14/2022] [Indexed: 11/08/2022]
Abstract
BACKGROUND Pathogenic prions (PrPSc) are amyloid-rich hydrophobic proteins which bind avidly to surgical surfaces and represent some of the most difficult targets during the reprocessing of reusable surgical instruments. In-vitro methods to amplify and detect the presence of otherwise undetectable prion contamination are available, but they do not measure associated infectivity. Most of these methods rely on the use of proteinase K, however this can lead to the loss of a substantial portion of PrPSc, potentially producing false negatives. AIM To develop a sensitive in-situ method without proteinase treatment for the dynamic quantification of amyloid accumulation in N2a #58 cells following 22L-prion infection from infected tissues and spiked stainless-steel surfaces. METHODS We spiked cultures of N2a #58 cells with the 22L prion strain in solution or dried on stainless-steel wires and directly measured the accumulation of prion amyloid aggregates over several passages using highly sensitive fluorescence microscopy. FINDINGS We demonstrated a 10-log dynamic range using our method to test residual prion infectivity, that was validated to show variable decontamination efficacy against prions from commercially available cleaning chemistries. CONCLUSIONS The new cell-based infectivity method presented here avoids partial or possibly total proteinase K digestion of PrPSc in samples for greater sensitivity, in addition to low cost, no ethical concerns, and adaptability to detect different prion strains. This method can be used to test cleaning chemistries' efficacy with greater sensitivity than measuring total residual proteins, which may not correlate with residual prion infectivity.
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Affiliation(s)
- T J Secker
- Environmental Healthcare Unit, School of Biological Sciences, University of Southampton, Southampton, UK
| | - R C Hervé
- Environmental Healthcare Unit, School of Biological Sciences, University of Southampton, Southampton, UK.
| | - C W Keevil
- Environmental Healthcare Unit, School of Biological Sciences, University of Southampton, Southampton, UK
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3
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Naeimi WR, Serio TR. Beyond Amyloid Fibers: Accumulation, Biological Relevance, and Regulation of Higher-Order Prion Architectures. Viruses 2022; 14:v14081635. [PMID: 35893700 PMCID: PMC9332770 DOI: 10.3390/v14081635] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 07/14/2022] [Accepted: 07/23/2022] [Indexed: 12/19/2022] Open
Abstract
The formation of amyloid fibers is associated with a diverse range of disease and phenotypic states. These amyloid fibers often assemble into multi-protofibril, high-order architectures in vivo and in vitro. Prion propagation in yeast, an amyloid-based process, represents an attractive model to explore the link between these aggregation states and the biological consequences of amyloid dynamics. Here, we integrate the current state of knowledge, highlight opportunities for further insight, and draw parallels to more complex systems in vitro. Evidence suggests that high-order fibril architectures are present ex vivo from disease relevant environments and under permissive conditions in vivo in yeast, including but not limited to those leading to prion formation or instability. The biological significance of these latter amyloid architectures or how they may be regulated is, however, complicated by inconsistent experimental conditions and analytical methods, although the Hsp70 chaperone Ssa1/2 is likely involved. Transition between assembly states could form a mechanistic basis to explain some confounding observations surrounding prion regulation but is limited by a lack of unified methodology to biophysically compare these assembly states. Future exciting experimental entryways may offer opportunities for further insight.
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4
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Serpa JJ, Popov KI, Petrotchenko EV, Dokholyan NV, Borchers CH. Structure of prion β-oligomers as determined by short-distance crosslinking constraint-guided discrete molecular dynamics simulations. Proteomics 2021; 21:e2000298. [PMID: 34482645 PMCID: PMC9285417 DOI: 10.1002/pmic.202000298] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Revised: 08/10/2021] [Accepted: 08/27/2021] [Indexed: 11/08/2022]
Abstract
The conversion of the native monomeric cellular prion protein (PrPC ) into an aggregated pathological β-oligomeric form (PrPβ ) and an infectious form (PrPSc ) is the central element in the development of prion diseases. The structure of the aggregates and the molecular mechanisms of the conformational changes involved in the conversion are still unknown. We applied mass spectrometry combined with chemical crosslinking, hydrogen/deuterium exchange, limited proteolysis, and surface modification for the differential characterization of the native and the urea+acid-converted prion β-oligomer structures to obtain insights into the mechanisms of conversion and aggregation. For the determination of the structure of the monomer and the dimer unit of the β-oligomer, we applied a recently-developed approach for de novo protein structure determination which is based on the incorporation of zero-length and short-distance crosslinking data as intra- and inter-protein constraints in discrete molecular dynamics simulations (CL-DMD). Based on all of the structural-proteomics experimental data and the computationally predicted structures of the monomer units, we propose the potential mode of assembly of the β-oligomer. The proposed β-oligomer assembly provides a clue on the β-sheet nucleation site, and how template-based conversion of the native prion molecule occurs, growth of the prion aggregates, and maturation into fibrils may occur.
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Affiliation(s)
- Jason J Serpa
- University of Victoria -Genome British Columbia Proteomics Centre, Victoria, British Columbia, Canada
| | - Konstantin I Popov
- Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Evgeniy V Petrotchenko
- Segal Cancer Proteomics Centre, Lady Davis Institute, Jewish General Hospital, McGill University, Montreal, Quebec, Canada.,Center for Computational and Data-Intensive Science and Engineering, Skolkovo Institute of Science and Technology, Moscow, Russia
| | - Nikolay V Dokholyan
- Department of Pharmacology, Department of Biochemistry & Molecular Biology, Pennsylvania State University College of Medicine, Hershey, Pennsylvania, USA
| | - Christoph H Borchers
- Segal Cancer Proteomics Centre, Lady Davis Institute, Jewish General Hospital, McGill University, Montreal, Quebec, Canada.,Center for Computational and Data-Intensive Science and Engineering, Skolkovo Institute of Science and Technology, Moscow, Russia.,Gerald Bronfman Department of Oncology, Jewish General Hospital, McGill University, Montreal, Quebec, Canada
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5
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Arshad H, Patel Z, Mehrabian M, Bourkas MEC, Al-Azzawi ZAM, Schmitt-Ulms G, Watts JC. The aminoglycoside G418 hinders de novo prion infection in cultured cells. J Biol Chem 2021; 297:101073. [PMID: 34390689 PMCID: PMC8413896 DOI: 10.1016/j.jbc.2021.101073] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Revised: 07/23/2021] [Accepted: 08/10/2021] [Indexed: 01/16/2023] Open
Abstract
The study of prions and the discovery of candidate therapeutics for prion disease have been facilitated by the ability of prions to replicate in cultured cells. Paradigms in which prion proteins from different species are expressed in cells with low or no expression of endogenous prion protein (PrP) have expanded the range of prion strains that can be propagated. In these systems, cells stably expressing a PrP of interest are typically generated via coexpression of a selectable marker and treatment with an antibiotic. Here, we report the unexpected discovery that the aminoglycoside G418 (Geneticin) interferes with the ability of stably transfected cultured cells to become infected with prions. In G418-resistant lines of N2a or CAD5 cells, the presence of G418 reduced levels of protease-resistant PrP following challenge with the RML or 22L strains of mouse prions. G418 also interfered with the infection of cells expressing hamster PrP with the 263K strain of hamster prions. Interestingly, G418 had minimal to no effect on protease-resistant PrP levels in cells with established prion infection, arguing that G418 selectively interferes with de novo prion infection. As G418 treatment had no discernible effect on cellular PrP levels or its localization, this suggests that G418 may specifically target prion assemblies or processes involved in the earliest stages of prion infection.
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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
| | - Mohadeseh Mehrabian
- 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
| | - Matthew E C Bourkas
- 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; Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | - 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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6
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Cortez LM, Nemani SK, Duque Velásquez C, Sriraman A, Wang Y, Wille H, McKenzie D, Sim VL. Asymmetric-flow field-flow fractionation of prions reveals a strain-specific continuum of quaternary structures with protease resistance developing at a hydrodynamic radius of 15 nm. PLoS Pathog 2021; 17:e1009703. [PMID: 34181702 PMCID: PMC8270404 DOI: 10.1371/journal.ppat.1009703] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Revised: 07/09/2021] [Accepted: 06/09/2021] [Indexed: 11/19/2022] Open
Abstract
Prion diseases are transmissible neurodegenerative disorders that affect mammals, including humans. The central molecular event is the conversion of cellular prion glycoprotein, PrPC, into a plethora of assemblies, PrPSc, associated with disease. Distinct phenotypes of disease led to the concept of prion strains, which are associated with distinct PrPSc structures. However, the degree to which intra- and inter-strain PrPSc heterogeneity contributes to disease pathogenesis remains unclear. Addressing this question requires the precise isolation and characterization of all PrPSc subpopulations from the prion-infected brains. Until now, this has been challenging. We used asymmetric-flow field-flow fractionation (AF4) to isolate all PrPSc subpopulations from brains of hamsters infected with three prion strains: Hyper (HY) and 263K, which produce almost identical phenotypes, and Drowsy (DY), a strain with a distinct presentation. In-line dynamic and multi-angle light scattering (DLS/MALS) data provided accurate measurements of particle sizes and estimation of the shape and number of PrPSc particles. We found that each strain had a continuum of PrPSc assemblies, with strong correlation between PrPSc quaternary structure and phenotype. HY and 263K were enriched with large, protease-resistant PrPSc aggregates, whereas DY consisted primarily of smaller, more protease-sensitive aggregates. For all strains, a transition from protease-sensitive to protease-resistant PrPSc took place at a hydrodynamic radius (Rh) of 15 nm and was accompanied by a change in glycosylation and seeding activity. Our results show that the combination of AF4 with in-line MALS/DLS is a powerful tool for analyzing PrPSc subpopulations and demonstrate that while PrPSc quaternary structure is a major contributor to PrPSc structural heterogeneity, a fundamental change, likely in secondary/tertiary structure, prevents PrPSc particles from maintaining proteinase K resistance below an Rh of 15 nm, regardless of strain. This results in two biochemically distinctive subpopulations, the proportion, seeding activity, and stability of which correlate with prion strain phenotype.
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Affiliation(s)
- Leonardo M Cortez
- Centre for Prions and Protein Folding Diseases, Edmonton, Alberta, Canada
- Department of Medicine, Division of Neurology, University of Alberta, Edmonton, Alberta, Canada
| | - Satish K Nemani
- Centre for Prions and Protein Folding Diseases, Edmonton, Alberta, Canada
- Department of Medicine, Division of Neurology, University of Alberta, Edmonton, Alberta, Canada
| | - Camilo Duque Velásquez
- Centre for Prions and Protein Folding Diseases, Edmonton, Alberta, Canada
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Aishwarya Sriraman
- Centre for Prions and Protein Folding Diseases, Edmonton, Alberta, Canada
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
| | - YongLiang Wang
- Centre for Prions and Protein Folding Diseases, Edmonton, Alberta, Canada
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
| | - Holger Wille
- Centre for Prions and Protein Folding Diseases, Edmonton, Alberta, Canada
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
| | - Debbie McKenzie
- Centre for Prions and Protein Folding Diseases, Edmonton, Alberta, Canada
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Valerie L Sim
- Centre for Prions and Protein Folding Diseases, Edmonton, Alberta, Canada
- Department of Medicine, Division of Neurology, University of Alberta, Edmonton, Alberta, Canada
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7
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Silva CJ, Onisko BC, Dynin IC, Erickson-Beltran M, Requena JR. Time of Detection of Prions in the Brain by Nanoscale Liquid Chromatography Coupled to Tandem Mass Spectrometry Is Comparable to Animal Bioassay. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2021; 69:2279-2286. [PMID: 33586964 DOI: 10.1021/acs.jafc.0c06241] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Prions cause transmissible and inevitably fatal neurological diseases in agriculturally important animals, including bovine spongiform encephalopathy in domestic cattle, scrapie in sheep and goats, and chronic wasting disease in cervids. Because animals are largely asymptomatic throughout the course of the disease, early detection of prion disease is important. Hamsters were peripherally (ip) inoculated with hamster-adapted (Sc237) prions. By week 13 of a 14-week disease course, clinical signs appeared. A multiple-reaction-monitoring-based method was used to quantitate the amount of proteinase-K-digested prions (PrP 27-30) and the extent of methionine 213 oxidation present in the brains of infected hamsters. Detectable amounts of PrP 27-30 were present in all animals after 4 weeks. The extent of methionine 213 oxidation decreased over time. When we compared our quantitation results to those from other researchers using bioassay, we observed that consistent detection of PrP 27-30 by mass spectrometry occurs at a time when prions are reliably detected by bioassay.
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Affiliation(s)
- Christopher J Silva
- Produce Safety & Microbiology Research Unit, Western Regional Research Center, Agricultural Research Service, United States Department of Agriculture, 800 Buchanan Street, Albany, California 94710, United States
| | - Bruce C Onisko
- OniPro Biosciences, Kensington, California 94707, United States
| | - Irina C Dynin
- Produce Safety & Microbiology Research Unit, Western Regional Research Center, Agricultural Research Service, United States Department of Agriculture, 800 Buchanan Street, Albany, California 94710, United States
| | - Melissa Erickson-Beltran
- Produce Safety & Microbiology Research Unit, Western Regional Research Center, Agricultural Research Service, United States Department of Agriculture, 800 Buchanan Street, Albany, California 94710, United States
| | - Jesús R Requena
- CIMUS Biomedical Research Institute & Department of Medical Sciences, University of Santiago de Compostela-IDIS, 15782 Santiago de Compostela, Spain
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8
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Shoup D, Priola SA. The Size and Stability of Infectious Prion Aggregates Fluctuate Dynamically during Cellular Uptake and Disaggregation. Biochemistry 2021; 60:398-411. [PMID: 33497187 DOI: 10.1021/acs.biochem.0c00923] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Prion diseases arise when PrPSc, an aggregated, infectious, and insoluble conformer of the normally soluble mammalian prion protein, PrPC, catalyzes the conversion of PrPC into more PrPSc, which then accumulates in the brain leading to disease. PrPSc is the primary, if not sole, component of the infectious prion. Despite the stability and protease insensitivity of PrPSc aggregates, they can be degraded after cellular uptake. However, how cells disassemble and degrade PrPSc is poorly understood. In this work, we analyzed how the protease sensitivity and size distribution of PrPSc aggregates from two different mouse-adapted prion strains, 22L, that can persistently infect cells and 87V, that cannot, changed during cellular uptake. We show that within the first 4 h following uptake large PrPSc aggregates from both prion strains become less resistant to digestion by proteinase K (PK) through a mechanism that is dependent upon the acidic environment of endocytic vesicles. We further show that during disassembly, PrPSc aggregates from both strains become more resistant to PK digestion through the apparent removal of protease-sensitive PrPSc, with PrPSc from the 87V strain disassembled more readily than PrPSc from the 22L strain. Taken together, our data demonstrate that the sizes and stabilities of PrPSc from different prion strains change during cellular uptake and degradation, thereby potentially impacting the ability of prions to infect cells.
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Affiliation(s)
- Daniel Shoup
- Rocky Mountain Laboratories, Laboratory of Persistent Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana 59840, United States
| | - Suzette A Priola
- Rocky Mountain Laboratories, Laboratory of Persistent Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana 59840, United States
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9
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Ascari LM, Rocha SC, Gonçalves PB, Vieira TCRG, Cordeiro Y. Challenges and Advances in Antemortem Diagnosis of Human Transmissible Spongiform Encephalopathies. Front Bioeng Biotechnol 2020; 8:585896. [PMID: 33195151 PMCID: PMC7606880 DOI: 10.3389/fbioe.2020.585896] [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: 07/21/2020] [Accepted: 09/28/2020] [Indexed: 12/18/2022] Open
Abstract
Transmissible spongiform encephalopathies (TSEs), also known as prion diseases, arise from the structural conversion of the monomeric, cellular prion protein (PrPC) into its multimeric scrapie form (PrPSc). These pathologies comprise a group of intractable, rapidly evolving neurodegenerative diseases. Currently, a definitive diagnosis of TSE relies on the detection of PrPSc and/or the identification of pathognomonic histological features in brain tissue samples, which are usually obtained postmortem or, in rare cases, by brain biopsy (antemortem). Over the past two decades, several paraclinical tests for antemortem diagnosis have been developed to preclude the need for brain samples. Some of these alternative methods have been validated and can provide a probable diagnosis when combined with clinical evaluation. Paraclinical tests include in vitro cell-free conversion techniques, such as the real-time quaking-induced conversion (RT-QuIC), as well as immunoassays, electroencephalography (EEG), and brain bioimaging methods, such as magnetic resonance imaging (MRI), whose importance has increased over the years. PrPSc is the main biomarker in TSEs, and the RT-QuIC assay stands out for its ability to detect PrPSc in cerebrospinal fluid (CSF), olfactory mucosa, and dermatome skin samples with high sensitivity and specificity. Other biochemical biomarkers are the proteins 14-3-3, tau, neuron-specific enolase (NSE), astroglial protein S100B, α-synuclein, and neurofilament light chain protein (NFL), but they are not specific for TSEs. This paper reviews the techniques employed for definite diagnosis, as well as the clinical and paraclinical methods for possible and probable diagnosis, both those in use currently and those no longer employed. We also discuss current criteria, challenges, and perspectives for TSE diagnosis. An early and accurate diagnosis may allow earlier implementation of strategies to delay or stop disease progression.
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Affiliation(s)
- Lucas M. Ascari
- Faculty of Pharmacy, Pharmaceutical Biotechnology Department, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Stephanie C. Rocha
- Faculty of Pharmacy, Pharmaceutical Biotechnology Department, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Priscila B. Gonçalves
- Faculty of Pharmacy, Pharmaceutical Biotechnology Department, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Tuane C. R. G. Vieira
- Institute of Medical Biochemistry Leopoldo de Meis, National Institute of Science and Technology for Structural Biology and Bioimaging, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Yraima Cordeiro
- Faculty of Pharmacy, Pharmaceutical Biotechnology Department, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
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10
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Silva CJ, Erickson-Beltran ML, Dynin IC. Quantifying the Role of Lysine in Prion Replication by Nano-LC Mass Spectrometry and Bioassay. Front Bioeng Biotechnol 2020; 8:562953. [PMID: 33072723 PMCID: PMC7542330 DOI: 10.3389/fbioe.2020.562953] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2020] [Accepted: 08/24/2020] [Indexed: 11/26/2022] Open
Abstract
Prions propagate by a template driven process, inducing the normal cellular isoform (PrPC) to adopt the prion (PrPSc) conformation. In PrPC, the positions of lysines are highly conserved and strongly influence prion propagation. In this study, covalent modification was used to quantitate the role of lysines in the PrPSc template that drives prion replication. The ε-amino group of lysines in the PrPSc (hamster-adapted scrapie Sc237) template was acetylated by either acetic anhydride (Ac2O) or the N-hydroxysuccinimide ester of acetic acid (Ac-NHS). The extent of lysine acetylation in PrPSc was quantitated by mass spectrometry or Western blot-based analysis. Identical samples were bioassayed to quantitate the loss of infectivity associated with lysine acetylation. The reduction of infectivity at the highest reagent concentration was approximately 90% (∼10-fold). Ten of the eleven prion lysines were acetylated to a greater extent (25−400-fold) than the observed loss of infectivity. Only one lysine, at position 220 (K220), had a reactivity that is consistent with the loss of infectivity. Although lysines are highly conserved and play a crucial role in converting PrPC into the PrPSc conformation, once that conformation is adopted, the lysines present in the PrPSc template play only a limited role in prion replication. In principle, this approach could be used to clarify the role of other amino acids in the replication of prions and other prion-like protein misfolding diseases.
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Affiliation(s)
- Christopher J Silva
- Western Regional Research Center, United States Department of Agriculture, Agricultural Research Service, Albany, CA, United States
| | - Melissa L Erickson-Beltran
- Western Regional Research Center, United States Department of Agriculture, Agricultural Research Service, Albany, CA, United States
| | - Irina C Dynin
- Western Regional Research Center, United States Department of Agriculture, Agricultural Research Service, Albany, CA, United States
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11
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Stepanchuk A, Tahir W, Nilsson KPR, Schatzl HM, Stys PK. Early detection of prion protein aggregation with a fluorescent pentameric oligothiophene probe using spectral confocal microscopy. J Neurochem 2020; 156:1033-1048. [PMID: 32799317 DOI: 10.1111/jnc.15148] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 07/14/2020] [Accepted: 07/31/2020] [Indexed: 11/30/2022]
Abstract
Misfolding of the prion protein (PrP) and templating of its pathological conformation onto cognate proteins causes a number of lethal disorders of central nervous system in humans and animals, such as Creutzfeldt-Jacob disease, chronic wasting disease and bovine spongiform encephalopathy. Structural rearrangement of PrPC into PrPSc promotes aggregation of misfolded proteins into β-sheet-rich fibrils, which can be visualized by conformationally sensitive fluorescent probes. Early detection of prion misfolding and deposition might provide useful insights into its pathophysiology. Pentameric formyl thiophene acetic acid (pFTAA) is a novel amyloid probe that was shown to sensitively detect various misfolded proteins, including PrP. Here, we compared sensitivity of pFTAA staining and spectral microscopy with conventional methods of prion detection in mouse brains infected with mouse-adapted 22L prions. pFTAA bound to prion deposits in mouse brain sections exhibited a red-shifted fluorescence emission spectrum, which quantitatively increased with disease progression. Small prion deposits were detected as early as 50 days post-inoculation, well before appearance of clinical signs. Moreover, we detected significant spectral shifts in the greater brain parenchyma as early as 25 days post-inoculation, rivaling the most sensitive conventional method (real-time quaking-induced conversion). These results showcase the potential of pFTAA staining combined with spectral imaging for screening of prion-infected tissue. Not only does this method have comparable sensitivity to established techniques, it is faster and technically simpler. Finally, this readout provides valuable information about the spatial distribution of prion aggregates across tissue in the earliest stages of infection, potentially providing valuable pathophysiological insight into prion transmission.
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Affiliation(s)
- Anastasiia Stepanchuk
- Department of Clinical Neurosciences, Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada
| | - Waqas Tahir
- Calgary Prion Research Unit, Department of Comparative Biology & Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - K Peter R Nilsson
- Department of Physics, Chemistry and Biology, Linköping University, Linköping, Sweden
| | - Hermann M Schatzl
- Calgary Prion Research Unit, Department of Comparative Biology & Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - Peter K Stys
- Department of Clinical Neurosciences, Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada
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12
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Tahir W, Abdulrahman B, Abdelaziz DH, Thapa S, Walia R, Schätzl HM. An astrocyte cell line that differentially propagates murine prions. J Biol Chem 2020; 295:11572-11583. [PMID: 32561641 PMCID: PMC7450132 DOI: 10.1074/jbc.ra120.012596] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 06/08/2020] [Indexed: 01/09/2023] Open
Abstract
Prion diseases are fatal infectious neurodegenerative disorders in human and animals caused by misfolding of the cellular prion protein (PrPC) into the pathological isoform PrPSc. Elucidating the molecular and cellular mechanisms underlying prion propagation may help to develop disease interventions. Cell culture systems for prion propagation have greatly advanced molecular insights into prion biology, but translation of in vitro to in vivo findings is often disappointing. A wider range of cell culture systems might help overcome these shortcomings. Here, we describe an immortalized mouse neuronal astrocyte cell line (C8D1A) that can be infected with murine prions. Both PrPC protein and mRNA levels in astrocytes were comparable with those in neuronal and non-neuronal cell lines permitting persistent prion infection. We challenged astrocytes with three mouse-adapted prion strains (22L, RML, and ME7) and cultured them for six passages. Immunoblotting results revealed that the astrocytes propagated 22L prions well over all six passages, whereas ME7 prions did not replicate, and RML prions replicated only very weakly after five passages. Immunofluorescence analysis indicated similar results for PrPSc. Interestingly, when we used prion conversion activity as a readout in real-time quaking-induced conversion assays with RML-infected cell lysates, we observed a strong signal over all six passages, comparable with that for 22L-infected cells. These data indicate that the C8D1A cell line is permissive to prion infection. Moreover, the propagated prions differed in conversion and proteinase K–resistance levels in these astrocytes. We propose that the C8D1A cell line could be used to decipher prion strain biology.
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Affiliation(s)
- Waqas Tahir
- Department of Comparative Biology & Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta, Canada.,Calgary Prion Research Unit, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
| | - Basant Abdulrahman
- Department of Comparative Biology & Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta, Canada.,Calgary Prion Research Unit, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.,Department of Biochemistry and Molecular Biology, Faculty of Pharmacy, Helwan University, Cairo, Egypt
| | - Dalia H Abdelaziz
- Department of Comparative Biology & Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta, Canada.,Calgary Prion Research Unit, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.,Department of Biochemistry and Molecular Biology, Faculty of Pharmacy, Helwan University, Cairo, Egypt
| | - Simrika Thapa
- Department of Comparative Biology & Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta, Canada.,Calgary Prion Research Unit, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
| | - Rupali Walia
- Department of Comparative Biology & Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta, Canada.,Calgary Prion Research Unit, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
| | - Hermann M Schätzl
- Department of Comparative Biology & Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta, Canada .,Calgary Prion Research Unit, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
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13
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Igel-Egalon A, Laferrière F, Tixador P, Moudjou M, Herzog L, Reine F, Torres JM, Laude H, Rezaei H, Béringue V. Crossing Species Barriers Relies on Structurally Distinct Prion Assemblies and Their Complementation. Mol Neurobiol 2020; 57:2572-2587. [PMID: 32239450 DOI: 10.1007/s12035-020-01897-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Accepted: 03/02/2020] [Indexed: 02/01/2023]
Abstract
Prion replication results from the autocatalytic templated assisted conversion of the host-encoded prion protein PrPC into misfolded, polydisperse PrPSc conformers. Structurally distinct PrPSc conformers can give rise to multiple prion strains. Within and between prion strains, the biological activity (replicative efficacy and specific infectivity) of PrPSc assemblies is size dependent and thus reflects an intrinsic structural heterogeneity. The contribution of such PrPSc heterogeneity across species prion adaptation, which is believed to be based on fit adjustment between PrPSc template(s) and host PrPC, has not been explored. To define the structural-to-fitness PrPSc landscape, we measured the relative capacity of size-fractionated PrPSc assemblies from different prion strains to cross mounting species barriers in transgenic mice expressing foreign PrPC. In the absence of a transmission barrier, the relative efficacy of the isolated PrPSc assemblies to induce the disease is like the efficacy observed in the homotypic context. However, in the presence of a transmission barrier, size fractionation overtly delays and even abrogates prion pathogenesis in both the brain and spleen tissues, independently of the infectivity load of the isolated assemblies. Altering by serial dilution PrPSc assembly content of non-fractionated inocula aberrantly reduces their specific infectivity, solely in the presence of a transmission barrier. This suggests that synergy between structurally distinct PrPSc assemblies in the inoculum is requested for crossing the species barrier. Our data support a mechanism whereby overcoming prion species barrier requires complementation between structurally distinct PrPSc assemblies. This work provides key insight into the "quasispecies" concept applied to prions, which would not necessarily rely on prion substrains as constituent but on structural PrPSc heterogeneity within prion population.
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Affiliation(s)
| | - Florent Laferrière
- Université Paris-Saclay, INRAE, UVSQ, VIM, 78350, Jouy-en-Josas, France.,Institute of Neurodegenerative Diseases, CNRS UMR5293, University of Bordeaux, Bordeaux, France
| | - Philippe Tixador
- Université Paris-Saclay, INRAE, UVSQ, VIM, 78350, Jouy-en-Josas, France
| | - Mohammed Moudjou
- Université Paris-Saclay, INRAE, UVSQ, VIM, 78350, Jouy-en-Josas, France
| | - Laetitia Herzog
- Université Paris-Saclay, INRAE, UVSQ, VIM, 78350, Jouy-en-Josas, France
| | - Fabienne Reine
- Université Paris-Saclay, INRAE, UVSQ, VIM, 78350, Jouy-en-Josas, France
| | - Juan Maria Torres
- Centro de Investigación en Sanidad Animal (CISA-INIA), Valdeolmos, Madrid, Spain
| | - Hubert Laude
- Université Paris-Saclay, INRAE, UVSQ, VIM, 78350, Jouy-en-Josas, France
| | - Human Rezaei
- Université Paris-Saclay, INRAE, UVSQ, VIM, 78350, Jouy-en-Josas, France.
| | - Vincent Béringue
- Université Paris-Saclay, INRAE, UVSQ, VIM, 78350, Jouy-en-Josas, France.
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14
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Lathe R, Darlix JL. Prion protein PrP nucleic acid binding and mobilization implicates retroelements as the replicative component of transmissible spongiform encephalopathy. Arch Virol 2020; 165:535-556. [PMID: 32025859 PMCID: PMC7024060 DOI: 10.1007/s00705-020-04529-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Accepted: 12/13/2019] [Indexed: 12/21/2022]
Abstract
The existence of more than 30 strains of transmissible spongiform encephalopathy (TSE) and the paucity of infectivity of purified PrPSc, as well as considerations of PrP structure, are inconsistent with the protein-only (prion) theory of TSE. Nucleic acid is a strong contender as a second component. We juxtapose two key findings: (i) PrP is a nucleic-acid-binding antimicrobial protein that is similar to retroviral Gag proteins in its ability to trigger reverse transcription. (ii) Retroelement mobilization is widely seen in TSE disease. Given further evidence that PrP also mediates nucleic acid transport into and out of the cell, a strong case is to be made that a second element – retroelement nucleic acid – bound to PrP constitutes the second component necessary to explain the multiple strains of TSE.
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Affiliation(s)
- Richard Lathe
- Division of Infection Medicine, University of Edinburgh School of Medicine, Edinburgh, UK. .,Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Pushchino, Moscow, Moscow Region, Russia.
| | - Jean-Luc Darlix
- Faculté de Pharmacie, Centre Nationale de la Recherche Scientifique (CNRS) Laboratory of Bioimaging and Pathologies (Unité Mixte de Recherche 7021), Université de Strasbourg, Illkirch, France.
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15
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Eraña H, Charco JM, Di Bari MA, Díaz-Domínguez CM, López-Moreno R, Vidal E, González-Miranda E, Pérez-Castro MA, García-Martínez S, Bravo S, Fernández-Borges N, Geijo M, D’Agostino C, Garrido J, Bian J, König A, Uluca-Yazgi B, Sabate R, Khaychuk V, Vanni I, Telling GC, Heise H, Nonno R, Requena JR, Castilla J. Development of a new largely scalable in vitro prion propagation method for the production of infectious recombinant prions for high resolution structural studies. PLoS Pathog 2019; 15:e1008117. [PMID: 31644574 PMCID: PMC6827918 DOI: 10.1371/journal.ppat.1008117] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Revised: 11/04/2019] [Accepted: 10/01/2019] [Indexed: 12/12/2022] Open
Abstract
The resolution of the three-dimensional structure of infectious prions at the atomic level is pivotal to understand the pathobiology of Transmissible Spongiform Encephalopathies (TSE), but has been long hindered due to certain particularities of these proteinaceous pathogens. Difficulties related to their purification from brain homogenates of disease-affected animals were resolved almost a decade ago by the development of in vitro recombinant prion propagation systems giving rise to highly infectious recombinant prions. However, lack of knowledge about the molecular mechanisms of the misfolding event and the complexity of systems such as the Protein Misfolding Cyclic Amplification (PMCA), have limited generating the large amounts of homogeneous recombinant prion preparations required for high-resolution techniques such as solid state Nuclear Magnetic Resonance (ssNMR) imaging. Herein, we present a novel recombinant prion propagation system based on PMCA that substitutes sonication with shaking thereby allowing the production of unprecedented amounts of multi-labeled, infectious recombinant prions. The use of specific cofactors, such as dextran sulfate, limit the structural heterogeneity of the in vitro propagated prions and makes possible, for the first time, the generation of infectious and likely homogeneous samples in sufficient quantities for studies with high-resolution structural techniques as demonstrated by the preliminary ssNMR spectrum presented here. Overall, we consider that this new method named Protein Misfolding Shaking Amplification (PMSA), opens new avenues to finally elucidate the three-dimensional structure of infectious prions.
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Affiliation(s)
- Hasier Eraña
- CIC bioGUNE, Derio (Bizkaia), Spain
- ATLAS Molecular Pharma S. L. Derio (Bizkaia), Spain
| | | | - Michele A. Di Bari
- Department of Veterinary Public Health and Food Safety, Istituto Superiore di Sanità, Rome, Italy
| | | | | | - Enric Vidal
- Centre de Recerca en Sanitat Animal (CReSA), UAB-IRTA, Barcelona, Spain
| | | | | | | | - Susana Bravo
- Proteomics Lab, IDIS, Santiago de Compostela, Spain
| | | | - Mariví Geijo
- Animal Health Department, NEIKER-Instituto Vasco de Investigación y Desarrollo Agrario, Derio (Bizkaia), Spain
| | - Claudia D’Agostino
- Department of Veterinary Public Health and Food Safety, Istituto Superiore di Sanità, Rome, Italy
| | - Joseba Garrido
- Animal Health Department, NEIKER-Instituto Vasco de Investigación y Desarrollo Agrario, Derio (Bizkaia), Spain
| | - Jifeng Bian
- Prion Research Center (PRC), Colorado State University, Fort Collins, Colorado, United States of America
| | - Anna König
- Institute of Complex Systems (ICS-6) and Jülich Center for Structural Biology (JuStruct), Forschungszentrum Jülich, Jülich, Germany
- Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | - Boran Uluca-Yazgi
- Institute of Complex Systems (ICS-6) and Jülich Center for Structural Biology (JuStruct), Forschungszentrum Jülich, Jülich, Germany
- Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | - Raimon Sabate
- Department of Pharmacy and Pharmaceutical Technology and Physical-Chemistry, Faculty of Pharmacy and Food Sciences, University of Barcelona, Spain
- Institute of Nanoscience and Nanotechnology (IN2UB), University of Barcelona, Spain
| | - Vadim Khaychuk
- Prion Research Center (PRC), Colorado State University, Fort Collins, Colorado, United States of America
| | - Ilaria Vanni
- Department of Veterinary Public Health and Food Safety, Istituto Superiore di Sanità, Rome, Italy
| | - Glenn C. Telling
- Prion Research Center (PRC), Colorado State University, Fort Collins, Colorado, United States of America
| | - Henrike Heise
- Institute of Complex Systems (ICS-6) and Jülich Center for Structural Biology (JuStruct), Forschungszentrum Jülich, Jülich, Germany
- Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | - Romolo Nonno
- Department of Veterinary Public Health and Food Safety, Istituto Superiore di Sanità, Rome, Italy
| | - Jesús R. Requena
- CIMUS Biomedical Research Institute, University of Santiago de Compostela-IDIS, Spain
| | - Joaquín Castilla
- CIC bioGUNE, Derio (Bizkaia), Spain
- IKERBasque, Basque Foundation for Science, Bilbao (Bizkaia), Spain
- * E-mail:
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16
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Hannaoui S, Arifin MI, Chang SC, Yu J, Gopalakrishnan P, Doh-Ura K, Schatzl HM, Gilch S. Cellulose ether treatment in vivo generates chronic wasting disease prions with reduced protease resistance and delayed disease progression. J Neurochem 2019; 152:727-740. [PMID: 31553058 PMCID: PMC7078990 DOI: 10.1111/jnc.14877] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Revised: 09/17/2019] [Accepted: 09/19/2019] [Indexed: 12/19/2022]
Abstract
Chronic wasting disease (CWD) is a prion disease of free-ranging and farmed cervids that is highly contagious because of extensive prion shedding and prion persistence in the environment. Previously, cellulose ether compounds (CEs) have been shown to significantly extend the survival of mice inoculated with mouse-adapted prion strains. In this study, we used CEs, TC-5RW, and 60SH-50, in vitro and in vivo to assess their efficacy to interfere with CWD prion propagation. In vitro, CEs inhibited CWD prion amplification in a dose-dependent manner. Transgenic mice over-expressing elk PrPC (tgElk) were injected subcutaneously with a single dose of either of the CEs, followed by intracerebral inoculation with different CWD isolates from white tailed deer, mule deer, or elk. All treated groups showed a prolonged survival of up to more than 30 % when compared to the control group regardless of the CWD isolate used for infection. The extended survival in the treated groups correlated with reduced proteinase K resistance of prions. Remarkably, passage of brain homogenates from treated or untreated animals in tgElk mice resulted in a prolonged life span of mice inoculated with homogenates from CE-treated mice (of + 17%) even in the absence of further treatment. Besides the delayed disease onset upon passage in TgElk mice, the reduced proteinase K resistance was maintained but less pronounced. Therefore, these compounds can be very useful in limiting the spread of CWD in captive and wild-ranging cervids.
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Affiliation(s)
- Samia Hannaoui
- Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, Hotchkiss Brain Institute, University of Calgary, Calgary, Canada
| | - Maria Immaculata Arifin
- Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, Hotchkiss Brain Institute, University of Calgary, Calgary, Canada
| | - Sheng Chun Chang
- Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, Hotchkiss Brain Institute, University of Calgary, Calgary, Canada
| | - Jie Yu
- Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, Hotchkiss Brain Institute, University of Calgary, Calgary, Canada
| | - Preetha Gopalakrishnan
- Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, Hotchkiss Brain Institute, University of Calgary, Calgary, Canada
| | - Katsumi Doh-Ura
- Department of Neurochemistry, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
| | - Hermann M Schatzl
- Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, Hotchkiss Brain Institute, University of Calgary, Calgary, Canada
| | - Sabine Gilch
- Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, Hotchkiss Brain Institute, University of Calgary, Calgary, Canada
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17
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Igel-Egalon A, Laferrière F, Moudjou M, Bohl J, Mezache M, Knäpple T, Herzog L, Reine F, Jas-Duval C, Doumic M, Rezaei H, Béringue V. Early stage prion assembly involves two subpopulations with different quaternary structures and a secondary templating pathway. Commun Biol 2019; 2:363. [PMID: 31602412 PMCID: PMC6778151 DOI: 10.1038/s42003-019-0608-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Accepted: 09/10/2019] [Indexed: 12/12/2022] Open
Abstract
The dynamics of aggregation and structural diversification of misfolded, host-encoded proteins in neurodegenerative diseases are poorly understood. In many of these disorders, including Alzheimer's, Parkinson's and prion diseases, the misfolded proteins are self-organized into conformationally distinct assemblies or strains. The existence of intrastrain structural heterogeneity is increasingly recognized. However, the underlying processes of emergence and coevolution of structurally distinct assemblies are not mechanistically understood. Here, we show that early prion replication generates two subsets of structurally different assemblies by two sequential processes of formation, regardless of the strain considered. The first process corresponds to a quaternary structural convergence, by reducing the parental strain polydispersity to generate small oligomers. The second process transforms these oligomers into larger ones, by a secondary autocatalytic templating pathway requiring the prion protein. This pathway provides mechanistic insights into prion structural diversification, a key determinant for prion adaptation and toxicity.
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Affiliation(s)
| | - Florent Laferrière
- VIM, INRA, Université Paris-Saclay, 78350 Jouy-en-Josas, France
- Present Address: Institute of Neurodegenerative Diseases, CNRS UMR5293, University of Bordeaux, Bordeaux, France
| | | | - Jan Bohl
- VIM, INRA, Université Paris-Saclay, 78350 Jouy-en-Josas, France
- LCP, CNRS, Université Paris Sud, 91400 Orsay, France
| | - Mathieu Mezache
- VIM, INRA, Université Paris-Saclay, 78350 Jouy-en-Josas, France
- INRIA, MAMBA, Université Paris VI, 75005 Paris, France
| | - Tina Knäpple
- VIM, INRA, Université Paris-Saclay, 78350 Jouy-en-Josas, France
| | - Laetitia Herzog
- VIM, INRA, Université Paris-Saclay, 78350 Jouy-en-Josas, France
| | - Fabienne Reine
- VIM, INRA, Université Paris-Saclay, 78350 Jouy-en-Josas, France
| | - Christelle Jas-Duval
- VIM, INRA, Université Paris-Saclay, 78350 Jouy-en-Josas, France
- Pathogenesis and Control of Chronic Infections, EFS, INSERM, University of Montpellier, 34000 Montpellier, France
| | - Marie Doumic
- INRIA, MAMBA, Université Paris VI, 75005 Paris, France
| | - Human Rezaei
- VIM, INRA, Université Paris-Saclay, 78350 Jouy-en-Josas, France
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18
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Abstract
Prion diseases are caused by the conversion of physiological PrPC into the pathogenic misfolded protein PrPSc, conferring new properties to PrPSc that vary upon prion strains. In this work, we analyze the thermostability of three prion strains (BSE, RML and 22L) that were heated at 98 °C for 2 hours. PrPSc resistance to proteinase K (PrPres), residual infectivity by mouse bioassay and in vitro templating activity by protein misfolding cyclic amplification (PMCA) were studied. Heated strains showed a huge loss of PrPres and a radically different infectivity loss: RML was the most thermolabile strain (6 to 7 log10 infectivity loss), followed by 22L (5 log10) while BSE was the most thermostable strain with low or null infectivity reduction showing a clear dissociation between PrPres and infectivity. These results indicate that thermostability is a strain-specific feature, measurable by PMCA and mouse bioassay, and a great tool to distinguish prion strains.
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19
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Bender H, Noyes N, Annis JL, Hitpas A, Mollnow L, Croak K, Kane S, Wagner K, Dow S, Zabel M. PrPC knockdown by liposome-siRNA-peptide complexes (LSPCs) prolongs survival and normal behavior of prion-infected mice immunotolerant to treatment. PLoS One 2019; 14:e0219995. [PMID: 31329627 PMCID: PMC6645518 DOI: 10.1371/journal.pone.0219995] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Accepted: 07/05/2019] [Indexed: 11/29/2022] Open
Abstract
Prion diseases are members of neurodegenerative protein misfolding diseases (NPMDs) that include Alzheimer's, Parkinson's and Huntington diseases, amyotrophic lateral sclerosis, tauopathies, traumatic brain injuries, and chronic traumatic encephalopathies. No known therapeutics extend survival or improve quality of life of humans afflicted with prion disease. We and others developed a new approach to NPMD therapy based on reducing the amount of the normal, host-encoded protein available as substrate for misfolding into pathologic forms, using RNA interference, a catabolic pathway that decreases levels of mRNA encoding a particular protein. We developed a therapeutic delivery system consisting of small interfering RNA (siRNA) complexed to liposomes and addressed to the central nervous system using a targeting peptide derived from rabies virus glycoprotein. These liposome-siRNA-peptide complexes (LSPCs) cross the blood-brain barrier and deliver PrP siRNA to neuronal cells to decrease expression of the normal cellular prion protein, PrPC, which acts as a substrate for prion replication. Here we show that LSPCs can extend survival and improve behavior of prion-infected mice that remain immunotolerant to treatment. LSPC treatment may be a viable therapy for prion and other NPMDs that can improve the quality of life of patients at terminal disease stages.
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Affiliation(s)
- Heather Bender
- Prion Research Center, Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, United States of America
- Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO, United States of America
| | - Noelle Noyes
- Prion Research Center, Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, United States of America
- Department of Veterinary Population Medicine, College of Veterinary Medicine, University of Minnesota, St. Paul, MN, United States of America
| | - Jessica L. Annis
- Prion Research Center, Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, United States of America
| | - Amanda Hitpas
- Prion Research Center, Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, United States of America
| | - Luke Mollnow
- Prion Research Center, Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, United States of America
| | - Kendra Croak
- Prion Research Center, Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, United States of America
| | - Sarah Kane
- Prion Research Center, Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, United States of America
| | - Kaitlyn Wagner
- Prion Research Center, Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, United States of America
| | - Steven Dow
- Prion Research Center, Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, United States of America
- Center for Immune and Regenerative Medicine, Department of Clinical Sciences, Colorado State University, Fort Collins, CO, United States of America
| | - Mark Zabel
- Prion Research Center, Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, United States of America
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20
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Heterogeneity and Architecture of Pathological Prion Protein Assemblies: Time to Revisit the Molecular Basis of the Prion Replication Process? Viruses 2019; 11:v11050429. [PMID: 31083283 PMCID: PMC6563208 DOI: 10.3390/v11050429] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Revised: 05/07/2019] [Accepted: 05/08/2019] [Indexed: 01/24/2023] Open
Abstract
Prions are proteinaceous infectious agents responsible for a range of neurodegenerative diseases in animals and humans. Prion particles are assemblies formed from a misfolded, β-sheet rich, aggregation-prone isoform (PrPSc) of the host-encoded cellular prion protein (PrPC). Prions replicate by recruiting and converting PrPC into PrPSc, by an autocatalytic process. PrPSc is a pleiomorphic protein as different conformations can dictate different disease phenotypes in the same host species. This is the basis of the strain phenomenon in prion diseases. Recent experimental evidence suggests further structural heterogeneity in PrPSc assemblies within specific prion populations and strains. Still, this diversity is rather seen as a size continuum of assemblies with the same core structure, while analysis of the available experimental data points to the existence of structurally distinct arrangements. The atomic structure of PrPSc has not been elucidated so far, making the prion replication process difficult to understand. All currently available models suggest that PrPSc assemblies exhibit a PrPSc subunit as core constituent, which was recently identified. This review summarizes our current knowledge on prion assembly heterogeneity down to the subunit level and will discuss its importance with regard to the current molecular principles of the prion replication process.
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21
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Mercer RC, Harris DA. Identification of anti-prion drugs and targets using toxicity-based assays. Curr Opin Pharmacol 2019; 44:20-27. [PMID: 30684854 DOI: 10.1016/j.coph.2018.12.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Revised: 12/18/2018] [Accepted: 12/20/2018] [Indexed: 01/24/2023]
Abstract
Prion diseases are untreatable and invariably fatal, making the discovery of effective therapeutic interventions a priority. Most candidate molecules have been discovered based on their ability to reduce the levels of PrPSc, the infectious form of the prion protein, in cultured neuroblastoma cells. We have employed an alternative assay, based on an abnormal cellular phenotype associated with a mutant prion protein, to discover a novel class of anti-prion compounds, the phenethyl piperidines. Using an assay that monitors the acute toxic effects of PrPSc on the synapses of cultured hippocampal neurons, we have identified p38 MAPK as a druggable pharmacological target that is already being pursued for the treatment of other human diseases. Organotypic brain slices, which can propagate prions and mimic several neuropathological features of the disease, have also been used to test inhibitory compounds. An effective anti-prion regimen will involve synergistic combination of drugs acting at multiple steps of the pathogenic process, resulting not only in reduction in prion levels but also suppression of neurotoxic signaling.
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Affiliation(s)
- Robert Cc Mercer
- Boston University School of Medicine, Boston, MA 02118, United States
| | - David A Harris
- Boston University School of Medicine, Boston, MA 02118, United States.
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22
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Le NTT, Wu B, Harris DA. Prion neurotoxicity. Brain Pathol 2019; 29:263-277. [PMID: 30588688 DOI: 10.1111/bpa.12694] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Accepted: 11/28/2018] [Indexed: 01/04/2023] Open
Abstract
Although the mechanisms underlying prion propagation and infectivity are now well established, the processes accounting for prion toxicity and pathogenesis have remained mysterious. These processes are of enormous clinical relevance as they hold the key to identification of new molecular targets for therapeutic intervention. In this review, we will discuss two broad areas of investigation relevant to understanding prion neurotoxicity. The first is the use of in vitro experimental systems that model key events in prion pathogenesis. In this context, we will describe a hippocampal neuronal culture system we developed that reproduces the earliest pathological alterations in synaptic morphology and function in response to PrPSc . This system has allowed us to define a core synaptotoxic signaling pathway involving the activation of NMDA and AMPA receptors, stimulation of p38 MAPK phosphorylation and collapse of the actin cytoskeleton in dendritic spines. The second area concerns a striking and unexpected phenomenon in which certain structural manipulations of the PrPC molecule itself, including introduction of N-terminal deletion mutations or binding of antibodies to C-terminal epitopes, unleash powerful toxic effects in cultured cells and transgenic mice. We will describe our studies of this phenomenon, which led to the recognition that it is related to the induction of large, abnormal ionic currents by the structurally altered PrP molecules. Our results suggest a model in which the flexible N-terminal domain of PrPC serves as a toxic effector which is regulated by intramolecular interactions with the globular C-terminal domain. Taken together, these two areas of study have provided important clues to underlying cellular and molecular mechanisms of prion neurotoxicity. Nevertheless, much remains to be done on this next frontier of prion science.
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Affiliation(s)
- Nhat T T Le
- Department of Biochemistry, Boston University School of Medicine, Boston, MA
| | - Bei Wu
- Department of Biochemistry, Boston University School of Medicine, Boston, MA
| | - David A Harris
- Department of Biochemistry, Boston University School of Medicine, Boston, MA
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23
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Mechanism of aggregation and membrane interactions of mammalian prion protein. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2018. [DOI: 10.1016/j.bbamem.2018.02.031] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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24
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Thapa S, Abdulrahman B, Abdelaziz DH, Lu L, Ben Aissa M, Schatzl HM. Overexpression of quality control proteins reduces prion conversion in prion-infected cells. J Biol Chem 2018; 293:16069-16082. [PMID: 30154245 PMCID: PMC6187620 DOI: 10.1074/jbc.ra118.002754] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Revised: 08/09/2018] [Indexed: 11/06/2022] Open
Abstract
Prion diseases are fatal infectious neurodegenerative disorders in humans and other animals and are caused by misfolding of the cellular prion protein (PrPC) into the pathological isoform PrPSc. These diseases have the potential to transmit within or between species, including zoonotic transmission to humans. Elucidating the molecular and cellular mechanisms underlying prion propagation and transmission is therefore critical for developing molecular strategies for disease intervention. We have shown previously that impaired quality control mechanisms directly influence prion propagation. In this study, we manipulated cellular quality control pathways in vitro by stably and transiently overexpressing selected quality control folding (ERp57) and cargo (VIP36) proteins and investigated the effects of this overexpression on prion propagation. We found that ERp57 or VIP36 overexpression in persistently prion-infected neuroblastoma cells significantly reduces the amount of PrPSc in immunoblots and prion-seeding activity in the real-time quaking-induced conversion (RT-QuIC) assay. Using different cell lines infected with various prion strains confirmed that this effect is not cell type– or prion strain–specific. Moreover, de novo prion infection revealed that the overexpression significantly reduced newly formed PrPSc in acutely infected cells. ERp57-overexpressing cells significantly overcame endoplasmic reticulum stress, as revealed by expression of lower levels of the stress markers BiP and CHOP, accompanied by a decrease in PrP aggregates. Furthermore, application of ERp57-expressing lentiviruses prolonged the survival of prion-infected mice. Taken together, improved cellular quality control via ERp57 or VIP36 overexpression impairs prion propagation and could be utilized as a potential therapeutic strategy.
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Affiliation(s)
- Simrika Thapa
- From the Calgary Prion Research Unit, University of Calgary, Calgary, Alberta T2N 4Z6, Canada.,the Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta T2N 4Z6, Canada
| | - Basant Abdulrahman
- From the Calgary Prion Research Unit, University of Calgary, Calgary, Alberta T2N 4Z6, Canada.,the Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta T2N 4Z6, Canada.,the Department of Biochemistry and Molecular Biology, Faculty of Pharmacy, Helwan University, 11795 Cairo, Egypt, and
| | - Dalia H Abdelaziz
- From the Calgary Prion Research Unit, University of Calgary, Calgary, Alberta T2N 4Z6, Canada.,the Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta T2N 4Z6, Canada.,the Department of Biochemistry and Molecular Biology, Faculty of Pharmacy, Helwan University, 11795 Cairo, Egypt, and
| | - Li Lu
- From the Calgary Prion Research Unit, University of Calgary, Calgary, Alberta T2N 4Z6, Canada.,the Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta T2N 4Z6, Canada
| | - Manel Ben Aissa
- From the Calgary Prion Research Unit, University of Calgary, Calgary, Alberta T2N 4Z6, Canada.,the Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta T2N 4Z6, Canada
| | - Hermann M Schatzl
- From the Calgary Prion Research Unit, University of Calgary, Calgary, Alberta T2N 4Z6, Canada, .,the Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta T2N 4Z6, Canada.,the Departments of Veterinary Sciences and of Molecular Biology, University of Wyoming, Laramie, Wyoming 82071
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25
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Silva CJ. Food Forensics: Using Mass Spectrometry To Detect Foodborne Protein Contaminants, as Exemplified by Shiga Toxin Variants and Prion Strains. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2018; 66:8435-8450. [PMID: 29860833 DOI: 10.1021/acs.jafc.8b01517] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Food forensicists need a variety of tools to detect the many possible food contaminants. As a result of its analytical flexibility, mass spectrometry is one of those tools. Use of the multiple reaction monitoring (MRM) method expands its use to quantitation as well as detection of infectious proteins (prions) and protein toxins, such as Shiga toxins. The sample processing steps inactivate prions and Shiga toxins; the proteins are digested with proteases to yield peptides suitable for MRM-based analysis. Prions are detected by their distinct physicochemical properties and differential covalent modification. Shiga toxin analysis is based on detecting peptides derived from the five identical binding B subunits comprising the toxin. 15N-labeled internal standards are prepared from cloned proteins. These examples illustrate the power of MRM, in that the same instrument can be used to safely detect and quantitate protein toxins, prions, and small molecules that might contaminate our food.
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Affiliation(s)
- Christopher J Silva
- Produce Safety and Microbiology Research Unit, Western Regional Research Center, Agricultural Research Service , United States Department of Agriculture , Albany , California 94710 , United States
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26
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Prion acute synaptotoxicity is largely driven by protease-resistant PrPSc species. PLoS Pathog 2018; 14:e1007214. [PMID: 30089152 PMCID: PMC6101418 DOI: 10.1371/journal.ppat.1007214] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Revised: 08/20/2018] [Accepted: 07/12/2018] [Indexed: 01/09/2023] Open
Abstract
Although misfolding of normal prion protein (PrPC) into abnormal conformers (PrPSc) is critical for prion disease pathogenesis our current understanding of the underlying molecular pathophysiology is rudimentary. Exploiting an electrophysiology paradigm, herein we report that at least modestly proteinase K (PK)-resistant PrPSc (PrPres) species are acutely synaptotoxic. Brief exposure to ex vivo PrPSc from two mouse-adapted prion strains (M1000 and MU02) prepared as crude brain homogenates (cM1000 and cMU02) and cell lysates from chronically M1000-infected RK13 cells (MoRK13-Inf) caused significant impairment of hippocampal CA1 region long-term potentiation (LTP), with the LTP disruption approximating that reported during the evolution of murine prion disease. Proof of PrPSc (especially PrPres) species as the synaptotoxic agent was demonstrated by: significant rescue of LTP following selective immuno-depletion of total PrP from cM1000 (dM1000); modestly PK-treated cM1000 (PK+M1000) retaining full synaptotoxicity; and restoration of the LTP impairment when employing reconstituted, PK-eluted, immuno-precipitated M1000 preparations (PK+IP-M1000). Additional detailed electrophysiological analyses exemplified by impairment of post-tetanic potentiation (PTP) suggest possible heightened pre-synaptic vulnerability to the acute synaptotoxicity. This dysfunction correlated with cumulative insufficiency of replenishment of the readily releasable pool (RRP) of vesicles during repeated high-frequency stimulation utilised for induction of LTP. Broadly comparable results with LTP and PTP impairment were obtained utilizing hippocampal slices from PrPC knockout (PrPo/o) mice, with cM1000 serial dilution assessments revealing similar sensitivity of PrPo/o and wild type (WT) slices. Size fractionation chromatography demonstrated that synaptotoxic PrP correlated with PK-resistant species >100kDa, consistent with multimeric PrPSc, with levels of these species >6 ng/ml appearing sufficient to induce synaptic dysfunction. Biochemical analyses of hippocampal slices manifesting acute synaptotoxicity demonstrated reduced levels of multiple key synaptic proteins, albeit with noteworthy differences in PrPo/o slices, while such changes were absent in hippocampi demonstrating rescued LTP through treatment with dM1000. Our findings offer important new mechanistic insights into the synaptic impairment underlying prion disease, enhancing prospects for development of targeted effective therapies. Misfolding of the normal prion protein (PrPC) into disease-associated conformations (PrPSc) is the critical initiating step for prion diseases. Similar to other neurodegenerative disorders, progressive failure of brain synapses is considered a primary deleterious event underpinning prion disease evolution. Our current understanding of the underlying mechanisms associated with synaptic failure is rudimentary contributing to difficulties in developing effective treatments. Herein we report the use of an electrophysiology paradigm that allowed us to demonstrate that at least modestly proteinase K (PK)-resistant PrPSc species from two mouse-adapted prion strains (M1000 and MU02) are directly synaptotoxic causing significant acute impairment of hippocampal CA1 region long-term potentiation (LTP). Of note, the LTP disruption approximated that reported in prion animal models. Additional detailed analyses provided novel pathophysiological insights suggesting possible heightened pre-synaptic vulnerability to the acute synaptotoxicity through impairment of replenishment of the readily releasable pool of neurotransmitter vesicles, while biochemical analyses demonstrated reduced levels of multiple key pre-and post-synaptic proteins. Broadly similar acute synaptic dysfunction and dose-response susceptibility were observed in slices from mice not expressing PrPC albeit with minor but noteworthy differences in electrophysiological and biochemical findings. Our study offers important new mechanistic insights into the synaptic impairment underlying prion disease, enhancing prospects for development effective therapies.
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Honda R, Yamaguchi KI, Elhelaly AE, Fuji M, Kuwata K. Poly-L-histidine inhibits prion propagation in a prion-infected cell line. Prion 2018; 12:226-233. [PMID: 30074430 DOI: 10.1080/19336896.2018.1505395] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
Abstract
Transmissible spongiform encephalopathies (TSEs) are a group of lethal neurodegenerative diseases involving the structural conversion of cellular prion protein (PrPC) into the pathogenic isoform (PrPSc) for which no effective treatment is currently available. Previous studies have implicated that a polymeric molecule with a repeating unit, such as pentosane polysulfate and polyamidoamide dendrimers, exhibits a potent anti-prion activity, suggesting that poly-(amino acid)s could be a candidate molecule for inhibiting prion propagation. Here, by screening a series of poly-(amino acid)s in a prion-infected neuroblastoma cell line (GTFK), we identified poly-L-His as a novel anti-prion compound with an IC50 value of 1.8 µg/mL (0.18 µM). This potent anti-prion activity was specific to a high-molecular-weight poly-L-His and absent in monomeric histidine or low-molecular-weight poly-L-His. Solution NMR data indicated that poly-L-His directly binds to the loop region connecting Helix 2 and Helix 3 of PrPC and sterically blocks the structural conversion toward PrPSc. Poly-L-His, however, did not inhibit prion propagation in a prion-infected mouse when administered intraperitoneally, suggesting that the penetration of blood-brain barrier and/or the chemical stability of this polypeptide must be addressed before its application in vivo. Taken together, this study revealed the potential use of poly-L-His as a novel treatment against TSEs. (203 words).
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Affiliation(s)
- Ryo Honda
- a United Graduate School of Drug Discovery and Medical Information Sciences , Gifu University , Gifu , Japan
| | | | - Abdelazim Elsayed Elhelaly
- a United Graduate School of Drug Discovery and Medical Information Sciences , Gifu University , Gifu , Japan
| | - Mitsuhiko Fuji
- a United Graduate School of Drug Discovery and Medical Information Sciences , Gifu University , Gifu , Japan
| | - Kazuo Kuwata
- a United Graduate School of Drug Discovery and Medical Information Sciences , Gifu University , Gifu , Japan.,c Department of Gene and Development , Graduate School of Medicine, Gifu University , Gifu , Japan
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Wang F, Wang X, Abskharon R, Ma J. Prion infectivity is encoded exclusively within the structure of proteinase K-resistant fragments of synthetically generated recombinant PrP Sc. Acta Neuropathol Commun 2018; 6:30. [PMID: 29699569 PMCID: PMC5921397 DOI: 10.1186/s40478-018-0534-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Accepted: 04/11/2018] [Indexed: 02/04/2023] Open
Abstract
Transmissible spongiform encephalopathies, also known as prion diseases, are a group of fatal neurodegenerative disorders affecting both humans and animals. The central pathogenic event in prion disease is the misfolding of normal prion protein (PrPC) into the pathogenic conformer, PrPSc, which self-replicates by converting PrPC to more of itself. The biochemical hallmark of PrPSc is its C-terminal resistance to proteinase K (PK) digestion, which has been historically used to define PrPSc and is still the most widely used characteristic for prion detection. We used PK-resistance as a biochemical measure for the generation of recombinant prion from bacterially expressed recombinant PrP. However, the existence of both PK- resistant and -sensitive PrPSc forms in animal and human prion disease led to the question of whether the in vitro-generated recombinant prion infectivity is due to the PK-resistant or -sensitive recombinant PrP forms. In this study, we compared undigested and PK-digested recombinant prions for their infectivity using both the classical rodent bioassay and the cell-based prion infectivity assay. Similar levels of infectivity were detected in PK-digested and -undigested samples by both assays. A time course study of recombinant prion propagation showed that the increased capability to seed the conversion of endogenous PrP in cultured cells coincided with an increase of the PK-resistant form of recombinant PrP. Moreover, prion infectivity diminished when recombinant prion was subjected to an extremely harsh PK digestion. These results demonstrated that the infectivity of recombinant prion is encoded within the structure of the PK-resistant PrP fragments. This characteristic of recombinant prion, that a simple PK digestion is able to eliminate all PK-sensitive (non-infectious) PrP species, makes possible a more homogenous material that will be ideal for dissecting the molecular basis of prion infectivity.
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29
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What Is Our Current Understanding of PrP Sc-Associated Neurotoxicity and Its Molecular Underpinnings? Pathogens 2017; 6:pathogens6040063. [PMID: 29194372 PMCID: PMC5750587 DOI: 10.3390/pathogens6040063] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Revised: 11/21/2017] [Accepted: 11/27/2017] [Indexed: 01/15/2023] Open
Abstract
The prion diseases are a collection of fatal, transmissible neurodegenerative diseases that cause rapid onset dementia and ultimately death. Uniquely, the infectious agent is a misfolded form of the endogenous cellular prion protein, termed PrPSc. Despite the identity of the molecular agent remaining the same, PrPSc can cause a range of diseases with hereditary, spontaneous or iatrogenic aetiologies. However, the link between PrPSc and toxicity is complex, with subclinical cases of prion disease discovered, and prion neurodegeneration without obvious PrPSc deposition. The toxic mechanisms by which PrPSc causes the extensive neuropathology are still poorly understood, although recent advances are beginning to unravel the molecular underpinnings, including oxidative stress, disruption of proteostasis and induction of the unfolded protein response. This review will discuss the diseases caused by PrPSc toxicity, the nature of the toxicity of PrPSc, and our current understanding of the downstream toxic signaling events triggered by the presence of PrPSc.
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30
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Simmons M, Ru G, Casalone C, Iulini B, Cassar C, Seuberlich T. DISCONTOOLS: Identifying gaps in controlling bovine spongiform encephalopathy. Transbound Emerg Dis 2017; 65 Suppl 1:9-21. [PMID: 28795509 DOI: 10.1111/tbed.12671] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Indexed: 11/29/2022]
Abstract
This article summarizes the 2016 update of the DISCONTOOLS project gap analysis on bovine spongiform encephalopathy (BSE), which was based on a combination of literature review and expert knowledge. Uncertainty still exists in relation to the pathogenesis, immunology and epidemiology of BSE, but provided that infected material is prohibited from entering the animal feed chain, cases should continue to decline. BSE does not appear to spread between cattle, but if new strains with this ability appear then control would be considerably more difficult. Atypical types of BSE (L-BSE and H-BSE) have been identified, which have different molecular patterns and pathology, and do not display the same clinical signs as classical BSE. Laboratory transmission experiments indicate that the L-BSE agent has zoonotic potential. There is no satisfactory conclusion regarding the origin of the BSE epidemic. C-BSE case numbers declined rapidly following strict controls banning ruminant protein in animal feed, but occasional cases still occur. It is unclear whether these more recent cases indicate inadequate implementation of the bans, or the possibility that C-BSE might occur spontaneously, as has been postulated for H- and L-BSE. All of this will have implications once existing bans and levels of surveillance are both relaxed. Immunochemical tests can only be applied post-mortem. There is no immunological basis for diagnosis in the live animal. All aspects of disease control are expensive, particularly surveillance, specified risk material removal and feed controls. There is pressure to relax feed controls, and concurrent pressure from other sources to reduce surveillance. While the cost benefit argument can be applied successfully to either of these approaches, it would be necessary to maintain the ban on intraspecies recycling and some baseline surveillance. However, the potential risk is not limited to intraspecies recycling; recycling with cross-species transmission may be an ideal way to select or/and modify properties of transmissible spongiform encephalopathies agents in the future.
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Affiliation(s)
- M Simmons
- OIE, National and EU Reference Laboratory for BSE and Scrapie, Department of Pathology, APHA Weybridge, Addlestone, Surrey, UK
| | - G Ru
- CEA - National Reference Laboratory for Transmissible Spongiform Encephalopathies, OIE Reference Laboratories for BSE and Scrapie, Unit of Biostatistics, Epidemiology and Risk Analysis, Istituto Zooprofilattico Sperimentale del Piemonte, Turin, Italy
| | - C Casalone
- CEA - National Reference Laboratory for Transmissible Spongiform Encephalopathies, OIE Reference Laboratories for BSE and Scrapie, Neuropathology Laboratory, Istituto Zooprofilattico Sperimentale del Piemonte, Turin, Italy
| | - B Iulini
- CEA - National Reference Laboratory for Transmissible Spongiform Encephalopathies, OIE Reference Laboratories for BSE and Scrapie, Neuropathology Laboratory, Istituto Zooprofilattico Sperimentale del Piemonte, Turin, Italy
| | - C Cassar
- OIE, National and EU Reference Laboratory for BSE and Scrapie, Department of Pathology, APHA Weybridge, Addlestone, Surrey, UK
| | - T Seuberlich
- NeuroCenter, OIE and National Reference Laboratories for BSE and Scrapie, Division of Neurological Sciences, Vetsuisse Faculty, Bern, Switzerland
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Marín-Moreno A, Fernández-Borges N, Espinosa JC, Andréoletti O, Torres JM. Transmission and Replication of Prions. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2017; 150:181-201. [PMID: 28838661 DOI: 10.1016/bs.pmbts.2017.06.014] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Transmissible spongiform encephalopathies (TSEs) are a group of progressive, invariably fatal diseases that affect the nervous system of many mammals including humans. The key molecular event in the pathogenesis of TSEs is the conversion of the cellular prion protein PrPC into a disease-associated isoform PrPSc. The "protein-only hypothesis" argues that PrPSc itself is the infectious agent. In effect, PrPSc can adopt several structures that represent different prion strains. The interspecies transmission of TSEs is difficult because of differences between the host and donor primary PrP sequence. However, transmission is not impossible as this occurred when bovine spongiform encephalopathy spread to humans causing variant Creutzfeldt-Jakob disease (vCJD). This event determined a need for a thorough understanding of prion replication and transmission so that we could be one step ahead of further threats for human health. This chapter focuses on these concepts and on new insights gained into prion propagation mechanisms.
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Affiliation(s)
| | | | - Juan C Espinosa
- Centro de Investigación en Sanidad Animal, CISA-INIA, Madrid, Spain
| | - Olivier Andréoletti
- UMR INRA-ENVT 1225, Interactions Hôte Agent Pathogène, Ecole Nationale Vétérinaire de Toulouse, Toulouse, France
| | - Juan M Torres
- Centro de Investigación en Sanidad Animal, CISA-INIA, Madrid, Spain.
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Senesi M, Lewis V, Kim JH, Adlard PA, Finkelstein DI, Collins SJ. In vivo prion models and the disconnection between transmissibility and neurotoxicity. Ageing Res Rev 2017; 36:156-164. [PMID: 28450269 DOI: 10.1016/j.arr.2017.03.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2016] [Revised: 02/03/2017] [Accepted: 03/17/2017] [Indexed: 02/01/2023]
Abstract
The primary causative event in the development of prion diseases is the misfolding of the normal prion protein (PrPC) into an ensemble of altered conformers (herein collectively denoted as PrPSc) that accumulate in the brain. Prominent amongst currently unresolved key aspects underpinning prion disease pathogenesis is whether transmission and toxicity are sub-served by different molecular species of PrPSc, which may directly impact on the development of effective targeted treatments. The use of murine models of prion disease has been of fundamental importance for probing the relationship between hypothesised "neurotoxic" and "transmissible" PrPSc and the associated kinetic profiles of their production during disease evolution, but unfortunately consensus has not been achieved. Recent in vivo studies have led to formulation of the "two-phase" hypothesis, which postulates that there is first an exponential increase in transmitting PrPSc species followed by an abrupt transition to propagation of neurotoxic PrPSc species. Such observations however, appear inconsistent with previous in vivo murine studies employing detailed time-course behavioural testing, wherein evidence of neurotoxicity could be detected early in disease progression. This review analyses the contributions of in vivo murine models attempting to provide insights into the relationship between transmitting and neurotoxic PrPSc species and explores possible refinements to the "two-phase hypothesis", that better accommodate the available historical and recent evidence.
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Affiliation(s)
- Matteo Senesi
- Department of Medicine, Royal Melbourne Hospital, The University of Melbourne, Parkville 3010, Australia
| | - Victoria Lewis
- Department of Medicine, Royal Melbourne Hospital, The University of Melbourne, Parkville 3010, Australia
| | - Jee H Kim
- The Florey Department of Neuroscience and Mental Health, The University of Melbourne, Parkville 3010, Australia
| | - Paul A Adlard
- The Florey Department of Neuroscience and Mental Health, The University of Melbourne, Parkville 3010, Australia
| | - David I Finkelstein
- The Florey Department of Neuroscience and Mental Health, The University of Melbourne, Parkville 3010, Australia
| | - Steven J Collins
- Department of Medicine, Royal Melbourne Hospital, The University of Melbourne, Parkville 3010, Australia; The Florey Department of Neuroscience and Mental Health, The University of Melbourne, Parkville 3010, Australia.
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Das NR, Miyata H, Hara H, Uchiyama K, Chida J, Yano M, Watanabe H, Kondoh G, Sakaguchi S. Effects of prion protein devoid of the N-terminal residues 25-50 on prion pathogenesis in mice. Arch Virol 2017; 162:1867-1876. [DOI: 10.1007/s00705-017-3295-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2016] [Accepted: 02/02/2017] [Indexed: 12/23/2022]
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Leske H, Hornemann S, Herrmann US, Zhu C, Dametto P, Li B, Laferriere F, Polymenidou M, Pelczar P, Reimann RR, Schwarz P, Rushing EJ, Wüthrich K, Aguzzi A. Protease resistance of infectious prions is suppressed by removal of a single atom in the cellular prion protein. PLoS One 2017; 12:e0170503. [PMID: 28207746 PMCID: PMC5313174 DOI: 10.1371/journal.pone.0170503] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2016] [Accepted: 12/16/2016] [Indexed: 11/18/2022] Open
Abstract
Resistance to proteolytic digestion has long been considered a defining trait of prions in tissues of organisms suffering from transmissible spongiform encephalopathies. Detection of proteinase K-resistant prion protein (PrPSc) still represents the diagnostic gold standard for prion diseases in humans, sheep and cattle. However, it has become increasingly apparent that the accumulation of PrPSc does not always accompany prion infections: high titers of prion infectivity can be reached also in the absence of protease resistant PrPSc. Here, we describe a structural basis for the phenomenon of protease-sensitive prion infectivity. We studied the effect on proteinase K (PK) resistance of the amino acid substitution Y169F, which removes a single oxygen atom from the β2–α2 loop of the cellular prion protein (PrPC). When infected with RML or the 263K strain of prions, transgenic mice lacking wild-type (wt) PrPC but expressing MoPrP169F generated prion infectivity at levels comparable to wt mice. The newly generated MoPrP169F prions were biologically indistinguishable from those recovered from prion-infected wt mice, and elicited similar pathologies in vivo. Surprisingly, MoPrP169F prions showed greatly reduced PK resistance and density gradient analyses showed a significant reduction in high-density aggregates. Passage of MoPrP169F prions into mice expressing wt MoPrP led to full recovery of protease resistance, indicating that no strain shift had taken place. We conclude that a subtle structural variation in the β2–α2 loop of PrPC affects the sensitivity of PrPSc to protease but does not impact prion replication and infectivity. With these findings a specific structural feature of PrPC can be linked to a physicochemical property of the corresponding PrPSc.
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Affiliation(s)
- Henning Leske
- Institute of Neuropathology, University Hospital of Zurich, University of Zurich, Schmelzbergstrasse 12, Zurich, Switzerland
| | - Simone Hornemann
- Institute of Neuropathology, University Hospital of Zurich, University of Zurich, Schmelzbergstrasse 12, Zurich, Switzerland
| | - Uli Simon Herrmann
- Institute of Neuropathology, University Hospital of Zurich, University of Zurich, Schmelzbergstrasse 12, Zurich, Switzerland
| | - Caihong Zhu
- Institute of Neuropathology, University Hospital of Zurich, University of Zurich, Schmelzbergstrasse 12, Zurich, Switzerland
| | - Paolo Dametto
- Institute of Neuropathology, University Hospital of Zurich, University of Zurich, Schmelzbergstrasse 12, Zurich, Switzerland
| | - Bei Li
- Institute of Neuropathology, University Hospital of Zurich, University of Zurich, Schmelzbergstrasse 12, Zurich, Switzerland
| | - Florent Laferriere
- Institute of Molecular Life Sciences, University of Zurich, Winterthurerstrasse 190, Zurich, Switzerland
| | - Magdalini Polymenidou
- Institute of Molecular Life Sciences, University of Zurich, Winterthurerstrasse 190, Zurich, Switzerland
| | - Pawel Pelczar
- Institute of Molecular Biology and Biophysics, ETH Zurich, Otto-Stern-Weg 5, Zurich, Switzerland
| | - Regina Rose Reimann
- Institute of Neuropathology, University Hospital of Zurich, University of Zurich, Schmelzbergstrasse 12, Zurich, Switzerland
| | - Petra Schwarz
- Institute of Neuropathology, University Hospital of Zurich, University of Zurich, Schmelzbergstrasse 12, Zurich, Switzerland
| | - Elisabeth Jane Rushing
- Institute of Neuropathology, University Hospital of Zurich, University of Zurich, Schmelzbergstrasse 12, Zurich, Switzerland
| | - Kurt Wüthrich
- Department of Integrative Structural and Computational Biology and Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA, United States of America
- * E-mail: (AA); , (KW)
| | - Adriano Aguzzi
- Institute of Neuropathology, University Hospital of Zurich, University of Zurich, Schmelzbergstrasse 12, Zurich, Switzerland
- * E-mail: (AA); , (KW)
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PrP Knockout Cells Expressing Transmembrane PrP Resist Prion Infection. J Virol 2017; 91:JVI.01686-16. [PMID: 27847358 DOI: 10.1128/jvi.01686-16] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Accepted: 11/01/2016] [Indexed: 11/20/2022] Open
Abstract
Glycosylphosphatidylinositol (GPI) anchoring of the prion protein (PrPC) influences PrPC misfolding into the disease-associated isoform, PrPres, as well as prion propagation and infectivity. GPI proteins are found in cholesterol- and sphingolipid-rich membrane regions called rafts. Exchanging the GPI anchor for a nonraft transmembrane sequence redirects PrPC away from rafts. Previous studies showed that nonraft transmembrane PrPC variants resist conversion to PrPres when transfected into scrapie-infected N2a neuroblastoma cells, likely due to segregation of transmembrane PrPC and GPI-anchored PrPres in distinct membrane environments. Thus, it remained unclear whether transmembrane PrPC might convert to PrPres if seeded by an exogenous source of PrPres not associated with host cell rafts and without the potential influence of endogenous expression of GPI-anchored PrPC To further explore these questions, constructs containing either a C-terminal wild-type GPI anchor signal sequence or a nonraft transmembrane sequence containing a flexible linker were expressed in a cell line derived from PrP knockout hippocampal neurons, NpL2. NpL2 cells have physiological similarities to primary neurons, representing a novel and advantageous model for studying transmissible spongiform encephalopathy (TSE) infection. Cells were infected with inocula from multiple prion strains and in different biochemical states (i.e., membrane bound as in brain microsomes from wild-type mice or purified GPI-anchorless amyloid fibrils). Only GPI-anchored PrPC supported persistent PrPres propagation. Our data provide strong evidence that in cell culture GPI anchor-directed membrane association of PrPC is required for persistent PrPres propagation, implicating raft microdomains as a location for conversion. IMPORTANCE Mechanisms of prion propagation, and what makes them transmissible, are poorly understood. Glycosylphosphatidylinositol (GPI) membrane anchoring of the prion protein (PrPC) directs it to specific regions of cell membranes called rafts. In order to test the importance of the raft environment on prion propagation, we developed a novel model for prion infection where cells expressing either GPI-anchored PrPC or transmembrane-anchored PrPC, which partitions it to a different location, were treated with infectious, misfolded forms of the prion protein, PrPres We show that only GPI-anchored PrPC was able to convert to PrPres and able to serially propagate. The results strongly suggest that GPI anchoring and the localization of PrPC to rafts are crucial to the ability of PrPC to propagate as a prion.
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Leblanc P, Arellano-Anaya ZE, Bernard E, Gallay L, Provansal M, Lehmann S, Schaeffer L, Raposo G, Vilette D. Isolation of Exosomes and Microvesicles from Cell Culture Systems to Study Prion Transmission. Methods Mol Biol 2017; 1545:153-176. [PMID: 27943213 DOI: 10.1007/978-1-4939-6728-5_11] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Extracellular vesicles (EVs) are composed of microvesicles and exosomes. Exosomes are small membrane vesicles (40-120 nm sized) of endosomal origin released in the extracellular medium from cells when multivesicular bodies fuse with the plasma membrane, whereas microvesicles (i.e., shedding vesicles, 100 nm to 1 μm sized) bud from the plasma membrane. Exosomes and microvesicles carry functional proteins and nucleic acids (especially mRNAs and microRNAs) that can be transferred to surrounding cells and tissues and can impact multiple dimensions of the cellular life. Most of the cells, if not all, from neuronal to immune cells, release exosomes and microvesicles in the extracellular medium, and all biological fluids including blood (serum/plasma), urine, cerebrospinal fluid, and saliva contain EVs.Prion-infected cultured cells are known to secrete infectivity into their environment. We characterized this cell-free form of prions and showed that infectivity was associated with exosomes. Since exosomes are produced by a variety of cells, including cells that actively accumulate prions, they could be a vehicle for infectivity in body fluids and could participate to the dissemination of prions in the organism. In addition, such infectious exosomes also represent a natural, simple, biological material to get key information on the abnormal PrP forms associated with infectivity.In this chapter, we describe first a method that allows exosomes and microvesicles isolation from prion-infected cell cultures and in a second time the strategies to characterize the prions containing exosomes and their ability to disseminate the prion agent.
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Affiliation(s)
- Pascal Leblanc
- CNRS UMR5239, LBMC, Ecole Normale Supérieure de Lyon, Lyon, 69007, France.
- Institut NeuroMyoGène (INMG), CNRS UMR5310 - INSERM U1217, Université de Lyon - Université Claude Bernard, Lyon, 69000, France.
| | | | | | - Laure Gallay
- CNRS UMR5239, LBMC, Ecole Normale Supérieure de Lyon, Lyon, 69007, France
- Institut NeuroMyoGène (INMG), CNRS UMR5310 - INSERM U1217, Université de Lyon - Université Claude Bernard, Lyon, 69000, France
| | | | | | - Laurent Schaeffer
- CNRS UMR5239, LBMC, Ecole Normale Supérieure de Lyon, Lyon, 69007, France
- Institut NeuroMyoGène (INMG), CNRS UMR5310 - INSERM U1217, Université de Lyon - Université Claude Bernard, Lyon, 69000, France
| | - Graça Raposo
- CNRS UMR144, Institut Curie, Paris, 75248, France
| | - Didier Vilette
- IHAP, Université de Toulouse, INRA, ENVT, Toulouse, France.
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Silva CJ, Erickson-Beltran ML, Hui C, Badiola JJ, Nicholson EM, Requena JR, Bolea R. Quantitating PrP Polymorphisms Present in Prions from Heterozygous Scrapie-Infected Sheep. Anal Chem 2016; 89:854-861. [PMID: 27936597 DOI: 10.1021/acs.analchem.6b03822] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Scrapie is a prion (PrPSc) disease of sheep. The incubation period of sheep scrapie is strongly influenced by polymorphisms at positions 136, 154, and 171 of a sheep's normal cellular prion protein (PrPC). Chymotrypsin was used to digest sheep recombinant PrP to identify a set of characteristic peptides [M132LGSXMSRPL141 (X = A or V), Y153XENMY158 (X,= H or R), and Y166RPVDXY172 (X = H, K, Q, or R)] that could be used to detect and quantitate polymorphisms at positions 136, 154, and 171 of sheep PrPC or PrPSc. These peptides were used to develop a multiple reaction monitoring method (MRM) to detect the amounts of a particular polymorphism in a sample of PrPSc isolated from sheep heterozygous for their PrPC proteins. The limit of detection for these peptides was less than 50 attomole. Spinal cord tissue from heterozygous (ARQ/VRQ or ARH/ARQ) scrapie-infected Rasa Aragonesa sheep was analyzed using this MRM method. Both sets of heterozygotes show the presence of both polymorphisms in PrPSc. This was true for samples containing both proteinase K (PK)-sensitive and PK-resistant PrPSc and samples containing only the PK-resistant PrPSc. These results show that heterozygous animals contain PrPSc that is composed of significant amounts of both PrP polymorphisms.
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Affiliation(s)
- Christopher J Silva
- Produce Safety & Microbiology Research Unit, Western Regional Research Center, United States Department of Agriculture, Agricultural Research Service , Albany, California 94710, United States
| | - Melissa L Erickson-Beltran
- Produce Safety & Microbiology Research Unit, Western Regional Research Center, United States Department of Agriculture, Agricultural Research Service , Albany, California 94710, United States
| | - Colleen Hui
- Produce Safety & Microbiology Research Unit, Western Regional Research Center, United States Department of Agriculture, Agricultural Research Service , Albany, California 94710, United States
| | - Juan José Badiola
- Veterinary Faculty, Centro de Investigación en Encefalopatías y Enfermedades Transmisibles Emergentes (CIEETE), Universidad de Zaragoza , 50013, Zaragoza Spain
| | - Eric M Nicholson
- Virus and Prion Research Unit, National Animal Disease Center, United States Department of Agriculture, Agricultural Research Service , Ames, Iowa 50010, United States
| | - Jesús R Requena
- CIMUS Biomedical Research Institute, University of Santiago de Compostela-IDIS , Santiago de Compostela, 15782 Spain
| | - Rosa Bolea
- Veterinary Faculty, Centro de Investigación en Encefalopatías y Enfermedades Transmisibles Emergentes (CIEETE), Universidad de Zaragoza , 50013, Zaragoza Spain
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The Structure of Mammalian Prions and Their Aggregates. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2016; 329:277-301. [PMID: 28109330 DOI: 10.1016/bs.ircmb.2016.08.013] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Prion diseases, such as Creutzfeldt-Jakob disease in humans, bovine spongiform encephalopathy in cattle, chronic wasting disease in cervids (i.e., deer, elk, moose, and reindeer), and sheep scrapie, are caused by the misfolding of the cellular prion protein (PrPC) into a disease-causing conformer (PrPSc). PrPC is a normal, GPI-anchored protein that is expressed on the surface of neurons and other cell types. The structure of PrPC is well understood, based on studies of recombinant PrP, which closely mimics the structure of native PrPC. In contrast, PrPSc is prone to aggregate into a variety of quaternary structures, such as oligomers, amorphous aggregates, and amyloid fibrils. The propensity of PrPSc to assemble into these diverse forms of aggregates is also responsible for our limited knowledge about its structure. Then again, the repeating nature of certain regular PrPSc aggregates has allowed (lower resolution) insights into the structure of the infectious conformer, establishing a four-rung β-solenoid structure as a key element of its architecture.
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Miyazawa K, Okada H, Masujin K, Iwamaru Y, Yokoyama T. Infectivity-associated PrP(Sc) and disease duration-associated PrP(Sc) of mouse BSE prions. Prion 2016; 9:394-403. [PMID: 26555211 PMCID: PMC4964868 DOI: 10.1080/19336896.2015.1111507] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Disease-related prion protein (PrPSc), which is a structural isoform of the host-encoded cellular prion protein, is thought to be a causative agent of transmissible spongiform encephalopathies. However, the specific role of PrPSc in prion pathogenesis and its relationship to infectivity remain controversial. A time-course study of prion-affected mice was conducted, which showed that the prion infectivity was not simply proportional to the amount of PrPSc in the brain. Centrifugation (20,000 ×g) of the brain homogenate showed that most of the PrPSc was precipitated into the pellet, and the supernatant contained only a slight amount of PrPSc. Interestingly, mice inoculated with the obtained supernatant showed incubation periods that were approximately 15 d longer than those of mice inoculated with the crude homogenate even though both inocula contained almost the same infectivity. Our results suggest that a small population of fine PrPSc may be responsible for prion infectivity and that large, aggregated PrPSc may contribute to determining prion disease duration.
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Affiliation(s)
- Kohtaro Miyazawa
- a Influenza and Prion Disease Research Center; National Institute of Animal Health ; Tsukuba , Ibaraki , Japan
| | - Hiroyuki Okada
- a Influenza and Prion Disease Research Center; National Institute of Animal Health ; Tsukuba , Ibaraki , Japan
| | - Kentaro Masujin
- a Influenza and Prion Disease Research Center; National Institute of Animal Health ; Tsukuba , Ibaraki , Japan
| | - Yoshifumi Iwamaru
- a Influenza and Prion Disease Research Center; National Institute of Animal Health ; Tsukuba , Ibaraki , Japan
| | - Takashi Yokoyama
- a Influenza and Prion Disease Research Center; National Institute of Animal Health ; Tsukuba , Ibaraki , Japan
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The Structural Architecture of an Infectious Mammalian Prion Using Electron Cryomicroscopy. PLoS Pathog 2016; 12:e1005835. [PMID: 27606840 PMCID: PMC5015997 DOI: 10.1371/journal.ppat.1005835] [Citation(s) in RCA: 108] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Accepted: 08/01/2016] [Indexed: 12/31/2022] Open
Abstract
The structure of the infectious prion protein (PrPSc), which is responsible for Creutzfeldt-Jakob disease in humans and bovine spongiform encephalopathy, has escaped all attempts at elucidation due to its insolubility and propensity to aggregate. PrPSc replicates by converting the non-infectious, cellular prion protein (PrPC) into the misfolded, infectious conformer through an unknown mechanism. PrPSc and its N-terminally truncated variant, PrP 27–30, aggregate into amorphous aggregates, 2D crystals, and amyloid fibrils. The structure of these infectious conformers is essential to understanding prion replication and the development of structure-based therapeutic interventions. Here we used the repetitive organization inherent to GPI-anchorless PrP 27–30 amyloid fibrils to analyze their structure via electron cryomicroscopy. Fourier-transform analyses of averaged fibril segments indicate a repeating unit of 19.1 Å. 3D reconstructions of these fibrils revealed two distinct protofilaments, and, together with a molecular volume of 18,990 Å3, predicted the height of each PrP 27–30 molecule as ~17.7 Å. Together, the data indicate a four-rung β-solenoid structure as a key feature for the architecture of infectious mammalian prions. Furthermore, they allow to formulate a molecular mechanism for the replication of prions. Knowledge of the prion structure will provide important insights into the self-propagation mechanisms of protein misfolding. The structure of the infectious prion (PrPSc), which is responsible for Creutzfeldt-Jakob disease in humans and bovine spongiform encephalopathy, has escaped all attempts at elucidation due to its propensity to aggregate. Here, we use the repetitive organization inherent in amyloid fibrils to analyze the structure of GPI-anchorless PrP 27–30 via electron cryomicroscopy. Fourier-transform analysis of averaged fibril segments indicates a repeating unit of 19.1 Å. In agreement with this observation, 3D reconstructions reveal that each fibril contains two distinct protofilaments and that the height of each PrP 27–30 molecule in these fibrils is ~17.7 Å. Together the data indicate a four-rung β-solenoid structure as a key feature for the architecture of infectious mammalian prions. The data conflict with all previous models for the structure of PrPSc and allow the formulation of a molecular mechanism for the replication of prions.
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A Neuronal Culture System to Detect Prion Synaptotoxicity. PLoS Pathog 2016; 12:e1005623. [PMID: 27227882 PMCID: PMC4881977 DOI: 10.1371/journal.ppat.1005623] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2016] [Accepted: 04/19/2016] [Indexed: 12/02/2022] Open
Abstract
Synaptic pathology is an early feature of prion as well as other neurodegenerative diseases. Although the self-templating process by which prions propagate is well established, the mechanisms by which prions cause synaptotoxicity are poorly understood, due largely to the absence of experimentally tractable cell culture models. Here, we report that exposure of cultured hippocampal neurons to PrPSc, the infectious isoform of the prion protein, results in rapid retraction of dendritic spines. This effect is entirely dependent on expression of the cellular prion protein, PrPC, by target neurons, and on the presence of a nine-amino acid, polybasic region at the N-terminus of the PrPC molecule. Both protease-resistant and protease-sensitive forms of PrPSc cause dendritic loss. This system provides new insights into the mechanisms responsible for prion neurotoxicity, and it provides a platform for characterizing different pathogenic forms of PrPSc and testing potential therapeutic agents. Prion diseases are fatal neurodegenerative disorders that cause memory loss, impaired coordination, and abnormal movements. The molecular culprit in prion diseases is PrPSc, an infectious isoform of a host-encoded glycoprotein (PrPC) that can propagate itself by a self-templating mechanism. Whether PrPSc itself is toxic to neurons, and if so, the cellular mechanisms by which it produces neuronal pathology are largely unknown, in part because of the absence of suitable cell culture models. We describe here a hippocampal neuronal cultural system to detect the toxic effect of PrPSc on dendritic spines, which are postsynaptic elements responsible for excitatory synaptic transmission, and which are implicated in learning, memory, and the earliest stages of neurodegenerative diseases. We found that purified, exogenously applied PrPSc causes acute retraction of dendritic spines, an effect that is entirely dependent on expression of PrPC by target neurons, and on the on the presence of a nine-amino acid, polybasic region at the N-terminus of the PrPC molecule. Both protease-resistant and protease-sensitive forms of PrPSc cause dendritic retraction. This system provides new insights into the mechanisms responsible for prion neurotoxicity, and it provides a platform for characterizing different pathogenic forms of PrPSc and testing potential therapeutic agents.
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42
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Strain-dependent profile of misfolded prion protein aggregates. Sci Rep 2016; 6:20526. [PMID: 26877167 PMCID: PMC4753423 DOI: 10.1038/srep20526] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Accepted: 01/05/2016] [Indexed: 12/21/2022] Open
Abstract
Prions are composed of the misfolded prion protein (PrPSc) organized in a variety of aggregates. An important question in the prion field has been to determine the identity of functional PrPSc aggregates. In this study, we used equilibrium sedimentation in sucrose density gradients to separate PrPSc aggregates from three hamster prion strains (Hyper, Drowsy, SSLOW) subjected to minimal manipulations. We show that PrPSc aggregates distribute in a wide range of arrangements and the relative proportion of each species depends on the prion strain. We observed a direct correlation between the density of the predominant PrPSc aggregates and the incubation periods for the strains studied. The relative presence of PrPSc in fractions of different sucrose densities was indicative of the protein deposits present in the brain as analyzed by histology. Interestingly, no association was found between sensitivity to proteolytic degradation and aggregation profiles. Therefore, the organization of PrP molecules in terms of the density of aggregates generated may determine some of the particular strain properties, whereas others are independent from it. Our findings may contribute to understand the mechanisms of strain variation and the role of PrPSc aggregates in prion-induced neurodegeneration.
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43
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Singh J, Udgaonkar JB. Unraveling the Molecular Mechanism of pH-Induced Misfolding and Oligomerization of the Prion Protein. J Mol Biol 2016; 428:1345-1355. [PMID: 26854758 DOI: 10.1016/j.jmb.2016.01.030] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2015] [Revised: 01/27/2016] [Accepted: 01/28/2016] [Indexed: 12/31/2022]
Abstract
The misfolding of the prion protein (PrP) to aggregated forms is linked to several neurodegenerative diseases. Misfolded oligomeric forms of PrP are associated with neurotoxicity and/or infectivity, but the molecular mechanism by which they form is still poorly understood. A reduction in pH is known to be a key factor that triggers misfolded oligomer formation by PrP, but the residues whose protonation is linked with misfolding remain unidentified. The structural consequences of the protonation of these residues also remain to be determined. In the current study, amino acid residues whose protonation is critical for PrP misfolding and oligomerization have been identified using site-directed mutagenesis and misfolding/oligomerization assays. It is shown that the protonation of either H186 or D201, which mimics the effects of pathogenic mutations (H186R and D201N) at both residue sites, is critically linked to the stability, misfolding and oligomerization of PrP. Hydrogen-deuterium exchange studies coupled with mass spectrometry show that the protonation of either H186 or D201 leads to the same common structural change: increased structural dynamics in helix 1 and that in the loop between helix 1 and β-strand 2. It is shown that the protonation of either of these residues is sufficient for accelerating misfolded oligomer formation, most likely because the protonation of either residue causes the same structural perturbation. Hence, the increased structural dynamics in helix 1 and that in the loop between helix 1 and β-strand 2 appear to play an early critical role in acid-induced misfolding of PrP.
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Affiliation(s)
- Jogender Singh
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bengaluru 560065, India
| | - Jayant B Udgaonkar
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bengaluru 560065, India.
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Singh J, Udgaonkar JB. The Pathogenic Mutation T182A Converts the Prion Protein into a Molten Globule-like Conformation Whose Misfolding to Oligomers but Not to Fibrils Is Drastically Accelerated. Biochemistry 2016; 55:459-69. [DOI: 10.1021/acs.biochem.5b01266] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Jogender Singh
- National Centre for Biological
Sciences, Tata Institute of Fundamental Research, Bengaluru 560065, India
| | - Jayant B. Udgaonkar
- National Centre for Biological
Sciences, Tata Institute of Fundamental Research, Bengaluru 560065, India
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45
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Moda F, T. Le TN, Aulić S, Bistaffa E, Campagnani I, Virgilio T, Indaco A, Palamara L, Andréoletti O, Tagliavini F, Legname G. Synthetic prions with novel strain-specified properties. PLoS Pathog 2015; 11:e1005354. [PMID: 26720726 PMCID: PMC4699842 DOI: 10.1371/journal.ppat.1005354] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Accepted: 11/30/2015] [Indexed: 01/10/2023] Open
Abstract
Prions are infectious proteins that possess multiple self-propagating structures. The information for strains and structural specific barriers appears to be contained exclusively in the folding of the pathological isoform, PrPSc. Many recent studies determined that de novo prion strains could be generated in vitro from the structural conversion of recombinant (rec) prion protein (PrP) into amyloidal structures. Our aim was to elucidate the conformational diversity of pathological recPrP amyloids and their biological activities, as well as to gain novel insights in characterizing molecular events involved in mammalian prion conversion and propagation. To this end we generated infectious materials that possess different conformational structures. Our methodology for the prion conversion of recPrP required only purified rec full-length mouse (Mo) PrP and common chemicals. Neither infected brain extracts nor amplified PrPSc were used. Following two different in vitro protocols recMoPrP converted to amyloid fibrils without any seeding factor. Mouse hypothalamic GT1 and neuroblastoma N2a cell lines were infected with these amyloid preparations as fast screening methodology to characterize the infectious materials. Remarkably, a large number of amyloid preparations were able to induce the conformational change of endogenous PrPC to harbor several distinctive proteinase-resistant PrP forms. One such preparation was characterized in vivo habouring a synthetic prion with novel strain specified neuropathological and biochemical properties. Prions are infectious proteins capable of acquiring multiple self-propagating structures. The information for strains and structural specific barriers appears to be contained exclusively in the folding of the pathological isoform, designated as PrPSc. During propagation, disease-associated conformer PrPSc coerces the physiological form, denoted as PrPC, to adopt the pathological isoform conformation. We describe here the generation of an array of infectious materials with different structural, morphological, biochemical and cell biological characteristics. After producing purified recombinant prion protein of the wild-type mouse full-length sequence in Escherichia coli, we polymerized the protein into various amyloid fibril conformations based on different amyloid preparations. We also applied a build-in methodology for screening amyloid preparations and generate infectious materials using an amyloid-infected cell culture assay. Some of the amyloid fibrils preparations were able to efficiently amplify in PMCA (Protein Misfolding Cyclic Amplification), and to induce endogenous PrPC to convert into PrPSc in both murine hypothalamic GT1 and neuroblastoma N2a cell lines. One such protocol lead to the generation of a novel synthetic prion strain in mice.
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Affiliation(s)
- Fabio Moda
- Unit of Neuropathology and Neurology 5, IRCCS Foundation Carlo Besta Neurological Institute, Milano, Italy
| | - Thanh-Nhat T. Le
- Laboratory of Prion Biology, Department of Neuroscience, Scuola Internazionale Superiore di Studi Avanzati (SISSA), Trieste, Ital,y
| | - Suzana Aulić
- Laboratory of Prion Biology, Department of Neuroscience, Scuola Internazionale Superiore di Studi Avanzati (SISSA), Trieste, Ital,y
| | - Edoardo Bistaffa
- Laboratory of Prion Biology, Department of Neuroscience, Scuola Internazionale Superiore di Studi Avanzati (SISSA), Trieste, Ital,y
| | - Ilaria Campagnani
- Unit of Neuropathology and Neurology 5, IRCCS Foundation Carlo Besta Neurological Institute, Milano, Italy
| | - Tommaso Virgilio
- Unit of Neuropathology and Neurology 5, IRCCS Foundation Carlo Besta Neurological Institute, Milano, Italy
| | - Antonio Indaco
- Unit of Neuropathology and Neurology 5, IRCCS Foundation Carlo Besta Neurological Institute, Milano, Italy
| | - Luisa Palamara
- Unit of Neuropathology and Neurology 5, IRCCS Foundation Carlo Besta Neurological Institute, Milano, Italy
| | - Olivier Andréoletti
- UMR INRA-ENVT, Physiopathologie Infectieuse et Parasitaire des Ruminants, Ecole Nationale Vétérinaire de Toulouse, Toulouse, France
| | - Fabrizio Tagliavini
- Unit of Neuropathology and Neurology 5, IRCCS Foundation Carlo Besta Neurological Institute, Milano, Italy
| | - Giuseppe Legname
- Laboratory of Prion Biology, Department of Neuroscience, Scuola Internazionale Superiore di Studi Avanzati (SISSA), Trieste, Ital,y
- ELETTRA Laboratory, Sincrotrone Trieste S.C.p.A, Basovizza, Trieste, Italy
- * E-mail:
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Vilette D, Laulagnier K, Huor A, Alais S, Simoes S, Maryse R, Provansal M, Lehmann S, Andreoletti O, Schaeffer L, Raposo G, Leblanc P. Efficient inhibition of infectious prions multiplication and release by targeting the exosomal pathway. Cell Mol Life Sci 2015; 72:4409-27. [PMID: 26047659 PMCID: PMC11113226 DOI: 10.1007/s00018-015-1945-8] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2015] [Revised: 05/06/2015] [Accepted: 05/28/2015] [Indexed: 10/23/2022]
Abstract
Exosomes are secreted membrane vesicles of endosomal origin present in biological fluids. Exosomes may serve as shuttles for amyloidogenic proteins, notably infectious prions, and may participate in their spreading in vivo. To explore the significance of the exosome pathway on prion infectivity and release, we investigated the role of the endosomal sorting complex required for transport (ESCRT) machinery and the need for ceramide, both involved in exosome biogenesis. Silencing of HRS-ESCRT-0 subunit drastically impairs the formation of cellular infectious prion due to an altered trafficking of cholesterol. Depletion of Tsg101-ESCRT-I subunit or impairment of the production of ceramide significantly strongly decreases infectious prion release. Together, our data reveal that ESCRT-dependent and -independent pathways can concomitantly regulate the exosomal secretion of infectious prion, showing that both pathways operate for the exosomal trafficking of a particular cargo. These data open up a new avenue to regulate prion release and propagation.
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Affiliation(s)
- Didier Vilette
- UMR INRA/ENVT 1225, Interactions Hôte Agent Pathogène, Toulouse, France.
| | - Karine Laulagnier
- CNRS, UMR5239, Laboratoire de Biologie Moléculaire de la Cellule (LBMC), ENS Lyon, 46 allée d'Italie, 69364, Lyon 7, France
- Inserm, U836, Neurodégénérescence et Plasticité, Institute of Neuroscience, Grenoble, France
| | - Alvina Huor
- UMR INRA/ENVT 1225, Interactions Hôte Agent Pathogène, Toulouse, France
| | - Sandrine Alais
- Centre International de Recherche en Infectiologie (CIRI), INSERM U1111, CNRS UMR5308, UCBL, ENS Lyon, Lyon, France
| | - Sabrina Simoes
- Institut Curie, CNRS-UMR144-Structure and Membrane Compartments, 26 rue d'Ulm, 75248, Paris Cedex 05, France
| | - Romao Maryse
- Institut Curie, CNRS-UMR144-Structure and Membrane Compartments, 26 rue d'Ulm, 75248, Paris Cedex 05, France
| | - Monique Provansal
- Institut de Médecine Régénératrice et de Biothérapie (I.M.R.B.), Physiopathologie, diagnostic et thérapie cellulaire des affections neurodégénératives, INSERM Université Montpellier 1 U1040 CHU de Montpellier, Université Montpellier 1, Montpellier, France
| | - Sylvain Lehmann
- Institut de Médecine Régénératrice et de Biothérapie (I.M.R.B.), Physiopathologie, diagnostic et thérapie cellulaire des affections neurodégénératives, INSERM Université Montpellier 1 U1040 CHU de Montpellier, Université Montpellier 1, Montpellier, France
| | | | - Laurent Schaeffer
- CNRS, UMR5239, Laboratoire de Biologie Moléculaire de la Cellule (LBMC), ENS Lyon, 46 allée d'Italie, 69364, Lyon 7, France
| | - Graça Raposo
- Institut Curie, CNRS-UMR144-Structure and Membrane Compartments, 26 rue d'Ulm, 75248, Paris Cedex 05, France
| | - Pascal Leblanc
- CNRS, UMR5239, Laboratoire de Biologie Moléculaire de la Cellule (LBMC), ENS Lyon, 46 allée d'Italie, 69364, Lyon 7, France.
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Singh J, Udgaonkar JB. Molecular Mechanism of the Misfolding and Oligomerization of the Prion Protein: Current Understanding and Its Implications. Biochemistry 2015; 54:4431-42. [PMID: 26171558 DOI: 10.1021/acs.biochem.5b00605] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Prion diseases, also known as transmissible spongiform encephalopathies, make up a group of fatal neurodegenerative disorders linked with the misfolding and aggregation of the prion protein (PrP). Although it is not yet understood how the misfolding of PrP induces neurodegeneration, it is widely accepted that the formation of misfolded prion protein (termed PrP(Sc)) is both the triggering event in the disease and the main component of the infectious agent responsible for disease transmission. Despite the clear involvement of PrP(Sc) in prion diseases, the exact composition of PrP(Sc) is not yet well-known. Recent studies show that misfolded oligomers of PrP could, however, be responsible for neurotoxicity and/or infectivity in the prion diseases. Hence, understanding the molecular mechanism of formation of the misfolded oligomers of PrP is critical for developing an understanding about the prion diseases and for developing anti-prion therapeutics. This review discusses recent advances in understanding the molecular mechanism of misfolded oligomer formation by PrP and its implications for the development of anti-prion therapeutics.
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Affiliation(s)
- Jogender Singh
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bengaluru 560065, India
| | - Jayant B Udgaonkar
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bengaluru 560065, India
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Wang X, McGovern G, Zhang Y, Wang F, Zha L, Jeffrey M, Ma J. Intraperitoneal Infection of Wild-Type Mice with Synthetically Generated Mammalian Prion. PLoS Pathog 2015; 11:e1004958. [PMID: 26136122 PMCID: PMC4489884 DOI: 10.1371/journal.ppat.1004958] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2014] [Accepted: 05/14/2015] [Indexed: 11/23/2022] Open
Abstract
The prion hypothesis postulates that the infectious agent in transmissible spongiform encephalopathies (TSEs) is an unorthodox protein conformation based agent. Recent successes in generating mammalian prions in vitro with bacterially expressed recombinant prion protein provide strong support for the hypothesis. However, whether the pathogenic properties of synthetically generated prion (rec-Prion) recapitulate those of naturally occurring prions remains unresolved. Using end-point titration assay, we showed that the in vitro prepared rec-Prions have infectious titers of around 104 LD50 / μg. In addition, intraperitoneal (i.p.) inoculation of wild-type mice with rec-Prion caused prion disease with an average survival time of 210 – 220 days post inoculation. Detailed pathological analyses revealed that the nature of rec-Prion induced lesions, including spongiform change, disease specific prion protein accumulation (PrP-d) and the PrP-d dissemination amongst lymphoid and peripheral nervous system tissues, the route and mechanisms of neuroinvasion were all typical of classical rodent prions. Our results revealed that, similar to naturally occurring prions, the rec-Prion has a titratable infectivity and is capable of causing prion disease via routes other than direct intra-cerebral challenge. More importantly, our results established that the rec-Prion caused disease is pathogenically and pathologically identical to naturally occurring contagious TSEs, supporting the concept that a conformationally altered protein agent is responsible for the infectivity in TSEs. The transmissible spongiform encephalopathies (TSEs) are a group of infectious neurodegenerative diseases affecting both humans and animals. The prion hypothesis postulates that prions are protein conformation based infectious agents responsible for TSE infectivity. Prions have been synthetically generated in vitro, but it remains unclear whether the properties of synthetically generated prion are the same as those of TSE agents and whether the disease caused by synthetically generated prion is identical to naturally occurring TSEs. In this study, we demonstrated that similar to the classical TSE agents, the synthetically generated prion has a titratable infectivity and is able to cause prion disease in wild-type mice via routes other than direct intra-cerebral inoculation. More importantly, we showed that the synthetically generated prion induced pathological changes, including the dissemination of disease-specific prion protein accumulation and the route and mechanism of neuroinvasion, were all typical of classical TSEs. These results demonstrate the similarity of synthetically generated prion to the infectious agent in TSEs, providing strong evidence supporting the prion hypothesis.
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Affiliation(s)
- Xinhe Wang
- Center for Neurodegenerative Science, Van Andel Research Institute, Grand Rapids, Michigan, United States of America
- Department of Molecular and Cellular Biochemistry, Ohio State University, Columbus, Ohio, United States of America
| | - Gillian McGovern
- Animal and Plant Health Agency, Lasswade Laboratory, Pentlands Science Park, Penicuik, Midlothian, Scotland
| | - Yi Zhang
- Department of Molecular and Cellular Biochemistry, Ohio State University, Columbus, Ohio, United States of America
- Key Laboratory of Brain Functional Genomics (East China Normal University), Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics (East China Normal University), School of Life Sciences, East China Normal University, Shanghai, China
| | - Fei Wang
- Center for Neurodegenerative Science, Van Andel Research Institute, Grand Rapids, Michigan, United States of America
- Department of Molecular and Cellular Biochemistry, Ohio State University, Columbus, Ohio, United States of America
| | - Liang Zha
- Department of Molecular and Cellular Biochemistry, Ohio State University, Columbus, Ohio, United States of America
| | - Martin Jeffrey
- Animal and Plant Health Agency, Lasswade Laboratory, Pentlands Science Park, Penicuik, Midlothian, Scotland
| | - Jiyan Ma
- Center for Neurodegenerative Science, Van Andel Research Institute, Grand Rapids, Michigan, United States of America
- Department of Molecular and Cellular Biochemistry, Ohio State University, Columbus, Ohio, United States of America
- Key Laboratory of Brain Functional Genomics (East China Normal University), Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics (East China Normal University), School of Life Sciences, East China Normal University, Shanghai, China
- * E-mail:
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49
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Frid K, Einstein O, Friedman-Levi Y, Binyamin O, Ben-Hur T, Gabizon R. Aggregation of MBP in chronic demyelination. Ann Clin Transl Neurol 2015; 2:711-21. [PMID: 26273684 PMCID: PMC4531054 DOI: 10.1002/acn3.207] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Accepted: 03/26/2015] [Indexed: 12/14/2022] Open
Abstract
Objectives Misfolding of key disease proteins to an insoluble state is associated with most neurodegenerative conditions, such as prion, Parkinson, and Alzheimer’s diseases. In this work, and by studying animal models of multiple sclerosis, we asked whether this is also the case for myelin basic protein (MBP) in the late and neurodegenerative phases of demyelinating diseases. Methods To this effect, we tested whether MBP, an essential myelin component, present prion-like properties in animal models of MS, as is the case for Cuprizone-induced chronic demyelination or chronic phases of Experimental Autoimmune Encephalomyelitis (EAE). Results We show here that while total levels of MBP were not reduced following extensive demyelination, part of these molecules accumulated thereafter as aggregates inside oligodendrocytes or around neuronal cells. In chronic EAE, MBP precipitated concomitantly with Tau, a marker of diverse neurodegenerative conditions, including MS. Most important, analysis of fractions from Triton X-100 floatation gradients suggest that the lipid composition of brain membranes in chronic EAE differs significantly from that of naïve mice, an effect which may relate to oxidative insults and subsequently prevent the appropriate insertion and compaction of new MBP in the myelin sheath, thereby causing its misfolding and aggregation. Interpretation Prion-like aggregation of MBP following chronic demyelination may result from an aberrant lipid composition accompanying this pathological status. Such aggregation of MBP may contribute to neuronal damage that occurs in the progressive phase of MS.
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Affiliation(s)
- Kati Frid
- Department of Neurology, The Agnes Ginges Center for Human Neurogenetics, Hadassah University Hospital Jerusalem, 91120, Israel
| | - Ofira Einstein
- Department of Neurology, The Agnes Ginges Center for Human Neurogenetics, Hadassah University Hospital Jerusalem, 91120, Israel
| | - Yael Friedman-Levi
- Department of Neurology, The Agnes Ginges Center for Human Neurogenetics, Hadassah University Hospital Jerusalem, 91120, Israel
| | - Orli Binyamin
- Department of Neurology, The Agnes Ginges Center for Human Neurogenetics, Hadassah University Hospital Jerusalem, 91120, Israel
| | - Tamir Ben-Hur
- Department of Neurology, The Agnes Ginges Center for Human Neurogenetics, Hadassah University Hospital Jerusalem, 91120, Israel
| | - Ruth Gabizon
- Department of Neurology, The Agnes Ginges Center for Human Neurogenetics, Hadassah University Hospital Jerusalem, 91120, Israel
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Proteinase K and the structure of PrPSc: The good, the bad and the ugly. Virus Res 2015; 207:120-6. [PMID: 25816779 DOI: 10.1016/j.virusres.2015.03.008] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Revised: 03/14/2015] [Accepted: 03/16/2015] [Indexed: 10/23/2022]
Abstract
Infectious proteins (prions) are, ironically, defined by their resistance to proteolytic digestion. A defining characteristic of the transmissible isoform of the prion protein (PrP(Sc)) is its partial resistance to proteinase K (PK) digestion. Diagnosis of prion disease typically relies upon immunodetection of PK-digested PrP(Sc) by Western blot, ELISA or immunohistochemical detection. PK digestion has also been used to detect differences in prion strains. Thus, PK has been a crucial tool to detect and, thereby, control the spread of prions. PK has also been used as a tool to probe the structure of PrP(Sc). Mass spectrometry and antibodies have been used to identify PK cleavage sites in PrP(Sc). These results have been used to identify the more accessible, flexible stretches connecting the β-strand components in PrP(Sc). These data, combined with physical constraints imposed by spectroscopic results, were used to propose a qualitative model for the structure of PrP(Sc). Assuming that PrP(Sc) is a four rung β-solenoid, we have threaded the PrP sequence to satisfy the PK proteolysis data and other experimental constraints.
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