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Christensen CS, Wang S, Li W, Yu D, Li HJ. Structural Variations of Prions and Prion-like Proteins Associated with Neurodegeneration. Curr Issues Mol Biol 2024; 46:6423-6439. [PMID: 39057026 PMCID: PMC11275340 DOI: 10.3390/cimb46070384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2024] [Revised: 06/18/2024] [Accepted: 06/21/2024] [Indexed: 07/28/2024] Open
Abstract
Neurodegeneration is becoming one of the leading causes of death worldwide as the population expands and grows older. There is a growing desire to understand the mechanisms behind prion proteins as well as the prion-like proteins that make up neurodegenerative diseases (NDs), including Alzheimer's disease (AD) and Parkinson's disease (PD). Both amyloid-β (Aβ) and hyperphosphorylated tau (p-tau) proteins behave in ways similar to those of the infectious form of the prion protein, PrPSc, such as aggregating, seeding, and replicating under not yet fully understood mechanisms, thus the designation of prion-like. This review aims to highlight the shared mechanisms between prion-like proteins and prion proteins in the structural variations associated with aggregation and disease development. These mechanisms largely focus on the dysregulation of protein homeostasis, self-replication, and protein aggregation, and this knowledge could contribute to diagnoses and treatments for the given NDs.
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Affiliation(s)
| | | | | | | | - Henry James Li
- School of Arts and Sciences, New York University Shanghai, 567 West Yang Si Road, Shanghai 200122, China; (C.S.C.); (S.W.); (W.L.); (D.Y.)
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2
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Cracco L, Cali I, Cohen ML, Aslam R, Notari S, Kong Q, Newell KL, Ghetti B, Appleby BS, Gambetti P. Efficient transmission of human prion diseases to a glycan-free prion protein-expressing host. Brain 2024; 147:1539-1552. [PMID: 38000783 PMCID: PMC10994570 DOI: 10.1093/brain/awad399] [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: 08/23/2023] [Accepted: 10/12/2023] [Indexed: 11/26/2023] Open
Abstract
It is increasingly evident that the association of glycans with the prion protein (PrP), a major post-translational modification, significantly impacts the pathogenesis of prion diseases. A recent bioassay study has provided evidence that the presence of PrP glycans decreases spongiform degeneration and disease-related PrP (PrPD) deposition in a murine model. We challenged (PRNPN181Q/197Q) transgenic (Tg) mice expressing glycan-free human PrP (TgGlyc-), with isolates from sporadic Creutzfeldt-Jakob disease subtype MM2 (sCJDMM2), sporadic fatal insomnia and familial fatal insomnia, three human prion diseases that are distinct but share histotypic and PrPD features. TgGlyc- mice accurately replicated the basic histotypic features associated with the three diseases but the transmission was characterized by high attack rates, shortened incubation periods and a greatly increased severity of the histopathology, including the presence of up to 40 times higher quantities of PrPD that formed prominent deposits. Although the engineered protease-resistant PrPD shared at least some features of the secondary structure and the presence of the anchorless PrPD variant with the wild-type PrPD, it exhibited different density gradient profiles of the PrPD aggregates and a higher stability index. The severity of the histopathological features including PrP deposition appeared to be related to the incubation period duration. These findings are clearly consistent with the protective role of the PrP glycans but also emphasize the complexity of the conformational changes that impact PrPD following glycan knockout. Future studies will determine whether these features apply broadly to other human prion diseases or are PrPD-type dependent.
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Affiliation(s)
- Laura Cracco
- Department of Pathology and Laboratory Medicine, Indiana University, School of Medicine, Indianapolis, IN 46202, USA
| | - Ignazio Cali
- Department of Pathology, Case Western Reserve University, School of Medicine, Cleveland, OH 44106, USA
- National Prion Disease Pathology Surveillance Center, Case Western Reserve University, School of Medicine, Cleveland, OH 44106, USA
| | - Mark L Cohen
- Department of Pathology, Case Western Reserve University, School of Medicine, Cleveland, OH 44106, USA
| | - Rabail Aslam
- Department of Pathology, Case Western Reserve University, School of Medicine, Cleveland, OH 44106, USA
| | - Silvio Notari
- Department of Pathology, Case Western Reserve University, School of Medicine, Cleveland, OH 44106, USA
| | - Qingzhong Kong
- Department of Pathology, Case Western Reserve University, School of Medicine, Cleveland, OH 44106, USA
- National Prion Disease Pathology Surveillance Center, Case Western Reserve University, School of Medicine, Cleveland, OH 44106, USA
- Department of Neurology, Case Western Reserve University, School of Medicine, Cleveland, OH 44106, USA
| | - Kathy L Newell
- Department of Pathology and Laboratory Medicine, Indiana University, School of Medicine, Indianapolis, IN 46202, USA
| | - Bernardino Ghetti
- Department of Pathology and Laboratory Medicine, Indiana University, School of Medicine, Indianapolis, IN 46202, USA
| | - Brian S Appleby
- Department of Pathology, Case Western Reserve University, School of Medicine, Cleveland, OH 44106, USA
- National Prion Disease Pathology Surveillance Center, Case Western Reserve University, School of Medicine, Cleveland, OH 44106, USA
- Department of Neurology, Case Western Reserve University, School of Medicine, Cleveland, OH 44106, USA
- Department of Psychiatry, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Pierluigi Gambetti
- Department of Pathology, Case Western Reserve University, School of Medicine, Cleveland, OH 44106, USA
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3
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Pasala C, Sharma S, Roychowdhury T, Moroni E, Colombo G, Chiosis G. N-Glycosylation as a Modulator of Protein Conformation and Assembly in Disease. Biomolecules 2024; 14:282. [PMID: 38540703 PMCID: PMC10968129 DOI: 10.3390/biom14030282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2024] [Revised: 02/19/2024] [Accepted: 02/22/2024] [Indexed: 05/01/2024] Open
Abstract
Glycosylation, a prevalent post-translational modification, plays a pivotal role in regulating intricate cellular processes by covalently attaching glycans to macromolecules. Dysregulated glycosylation is linked to a spectrum of diseases, encompassing cancer, neurodegenerative disorders, congenital disorders, infections, and inflammation. This review delves into the intricate interplay between glycosylation and protein conformation, with a specific focus on the profound impact of N-glycans on the selection of distinct protein conformations characterized by distinct interactomes-namely, protein assemblies-under normal and pathological conditions across various diseases. We begin by examining the spike protein of the SARS virus, illustrating how N-glycans regulate the infectivity of pathogenic agents. Subsequently, we utilize the prion protein and the chaperone glucose-regulated protein 94 as examples, exploring instances where N-glycosylation transforms physiological protein structures into disease-associated forms. Unraveling these connections provides valuable insights into potential therapeutic avenues and a deeper comprehension of the molecular intricacies that underlie disease conditions. This exploration of glycosylation's influence on protein conformation effectively bridges the gap between the glycome and disease, offering a comprehensive perspective on the therapeutic implications of targeting conformational mutants and their pathologic assemblies in various diseases. The goal is to unravel the nuances of these post-translational modifications, shedding light on how they contribute to the intricate interplay between protein conformation, assembly, and disease.
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Affiliation(s)
- Chiranjeevi Pasala
- Chemical Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; (C.P.); (S.S.); (T.R.)
| | - Sahil Sharma
- Chemical Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; (C.P.); (S.S.); (T.R.)
| | - Tanaya Roychowdhury
- Chemical Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; (C.P.); (S.S.); (T.R.)
| | - Elisabetta Moroni
- The Institute of Chemical Sciences and Technologies (SCITEC), Italian National Research Council (CNR), 20131 Milano, Italy; (E.M.); (G.C.)
| | - Giorgio Colombo
- The Institute of Chemical Sciences and Technologies (SCITEC), Italian National Research Council (CNR), 20131 Milano, Italy; (E.M.); (G.C.)
- Department of Chemistry, University of Pavia, 27100 Pavia, Italy
| | - Gabriela Chiosis
- Chemical Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; (C.P.); (S.S.); (T.R.)
- Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
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4
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Schilling KM, Jorwal P, Ubilla-Rodriguez NC, Assafa TE, Gatdula JRP, Vultaggio JS, Harris DA, Millhauser GL. N-glycosylation is a potent regulator of prion protein neurotoxicity. J Biol Chem 2023; 299:105101. [PMID: 37507020 PMCID: PMC10469999 DOI: 10.1016/j.jbc.2023.105101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 07/05/2023] [Accepted: 07/25/2023] [Indexed: 07/30/2023] Open
Abstract
The C-terminal domain of the cellular prion protein (PrPC) contains two N-linked glycosylation sites, the occupancy of which impacts disease pathology. In this study, we demonstrate that glycans at these sites are required to maintain an intramolecular interaction with the N-terminal domain, mediated through a previously identified copper-histidine tether, which suppresses the neurotoxic activity of PrPC. NMR and electron paramagnetic resonance spectroscopy demonstrate that the glycans refine the structure of the protein's interdomain interaction. Using whole-cell patch-clamp electrophysiology, we further show that cultured cells expressing PrP molecules with mutated glycosylation sites display large, spontaneous inward currents, a correlate of PrP-induced neurotoxicity. Our findings establish a structural basis for the role of N-linked glycans in maintaining a nontoxic, physiological fold of PrPC.
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Affiliation(s)
- Kevin M Schilling
- Department of Chemistry and Biochemistry, University of California, Santa Cruz, California, USA
| | - Pooja Jorwal
- Department of Biochemistry, Chobanian & Avedisian School of Medicine, Boston University, Boston, Massachusetts, USA
| | | | - Tufa E Assafa
- Department of Chemistry and Biochemistry, University of California, Santa Cruz, California, USA
| | - Jean R P Gatdula
- Department of Biochemistry, Chobanian & Avedisian School of Medicine, Boston University, Boston, Massachusetts, USA
| | - Janelle S Vultaggio
- Department of Biochemistry, Chobanian & Avedisian School of Medicine, Boston University, Boston, Massachusetts, USA
| | - David A Harris
- Department of Biochemistry, Chobanian & Avedisian School of Medicine, Boston University, Boston, Massachusetts, USA.
| | - Glenn L Millhauser
- Department of Chemistry and Biochemistry, University of California, Santa Cruz, California, USA.
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5
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Igel A, Fornara B, Rezaei H, Béringue V. Prion assemblies: structural heterogeneity, mechanisms of formation, and role in species barrier. Cell Tissue Res 2022; 392:149-166. [PMID: 36399162 PMCID: PMC10113350 DOI: 10.1007/s00441-022-03700-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Accepted: 11/03/2022] [Indexed: 11/19/2022]
Abstract
AbstractPrions are proteinaceous pathogens responsible for a wide range of neurodegenerative diseases in animal and human. Prions are formed from misfolded, ß-sheet rich, and aggregated conformers (PrPSc) of the host-encoded prion protein (PrPC). Prion replication stems from the capacity of PrPSc to self-replicate by templating PrPC conversion and polymerization. The question then arises about the molecular mechanisms of prion replication, host invasion, and capacity to contaminate other species. Studying these mechanisms has gained in recent years further complexity with evidence that PrPSc is a pleiomorphic protein. There is indeed compelling evidence for PrPSc structural heterogeneity at different scales: (i) within prion susceptible host populations with the existence of different strains with specific biological features due to different PrPSc conformers, (ii) within a single infected host with the co-propagation of different strains, and (iii) within a single strain with evidence for co-propagation of PrPSc assemblies differing in their secondary to quaternary structure. This review summarizes current knowledge of prion assembly heterogeneity, potential mechanisms of formation during the replication process, and importance when crossing the species barrier.
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6
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Otero A, Barrio T, Eraña H, Charco JM, Betancor M, Díaz-Domínguez CM, Marín B, Andréoletti O, Torres JM, Kong Q, Badiola JJ, Bolea R, Castilla J. Glycans are not necessary to maintain the pathobiological features of bovine spongiform encephalopathy. PLoS Pathog 2022; 18:e1010900. [PMID: 36206325 PMCID: PMC9581369 DOI: 10.1371/journal.ppat.1010900] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 10/19/2022] [Accepted: 09/27/2022] [Indexed: 12/02/2022] Open
Abstract
The role of the glycosylation status of PrPC in the conversion to its pathological counterpart and on cross-species transmission of prion strains has been widely discussed. Here, we assessed the effect on strain characteristics of bovine spongiform encephalopathy (BSE) isolates with different transmission histories upon propagation on a model expressing a non-glycosylated human PrPC. Bovine, ovine and porcine-passaged BSE, and variant Creutzfeldt-Jakob disease (vCJD) isolates were used as seeds/inocula in both in vitro and in vivo propagation assays using the non-glycosylated human PrPC-expressing mouse model (TgNN6h). After protein misfolding cyclic amplification (PMCA), all isolates maintained the biochemical characteristics of BSE. On bioassay, all PMCA-propagated BSE prions were readily transmitted to TgNN6h mice, in agreement with our previous in vitro results. TgNN6h mice reproduced the characteristic neuropathological and biochemical hallmarks of BSE, suggesting that the absence of glycans did not alter the pathobiological features of BSE prions. Moreover, back-passage of TgNN6h-adapted BSE prions to BoTg110 mice recovered the full BSE phenotype, confirming that the glycosylation of human PrPC is not essential for the preservation of the human transmission barrier for BSE prions or for the maintenance of BSE strain properties.
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Affiliation(s)
- Alicia Otero
- Centro de Encefalopatías y Enfermedades Transmisibles Emergentes, Universidad de Zaragoza, IA2, ISS Aragón, Zaragoza, Spain
| | - Tomás Barrio
- UMR INRAE-ENVT 1225 Interactions Hôtes-Agents Pathogènes (IHAP), Institute Nationale de Recherche pour l’Alimentation, l’Agriculture et l’Environnement (INRAE)—École Nationale Vétérinaire de Toulouse (ENVT), Université de Toulouse, Toulouse, France
| | - Hasier Eraña
- Center for Cooperative Research in Biosciences (CIC BioGUNE), Basque Research and Technology Alliance (BRTA), Prion Research Lab, Derio, Spain
- Atlas Molecular Pharma S. L., Derio, Spain
| | - Jorge M. Charco
- Center for Cooperative Research in Biosciences (CIC BioGUNE), Basque Research and Technology Alliance (BRTA), Prion Research Lab, Derio, Spain
- Atlas Molecular Pharma S. L., Derio, Spain
| | - Marina Betancor
- Centro de Encefalopatías y Enfermedades Transmisibles Emergentes, Universidad de Zaragoza, IA2, ISS Aragón, Zaragoza, Spain
| | - Carlos M. Díaz-Domínguez
- Center for Cooperative Research in Biosciences (CIC BioGUNE), Basque Research and Technology Alliance (BRTA), Prion Research Lab, Derio, Spain
| | - Belén Marín
- Centro de Encefalopatías y Enfermedades Transmisibles Emergentes, Universidad de Zaragoza, IA2, ISS Aragón, Zaragoza, Spain
| | - Olivier Andréoletti
- UMR INRAE-ENVT 1225 Interactions Hôtes-Agents Pathogènes (IHAP), Institute Nationale de Recherche pour l’Alimentation, l’Agriculture et l’Environnement (INRAE)—École Nationale Vétérinaire de Toulouse (ENVT), Université de Toulouse, Toulouse, France
| | - Juan M. Torres
- Centro de Investigación en Sanidad Animal, CISA-INIA, Valdeolmos, Madrid, Spain
| | - Qingzhong Kong
- Departments of Pathology and Neurology & National Center for Regenerative Medicine, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Juan J. Badiola
- Centro de Encefalopatías y Enfermedades Transmisibles Emergentes, Universidad de Zaragoza, IA2, ISS Aragón, Zaragoza, Spain
| | - Rosa Bolea
- Centro de Encefalopatías y Enfermedades Transmisibles Emergentes, Universidad de Zaragoza, IA2, ISS Aragón, Zaragoza, Spain
- * E-mail: (JC); (RB)
| | - Joaquín Castilla
- Center for Cooperative Research in Biosciences (CIC BioGUNE), Basque Research and Technology Alliance (BRTA), Prion Research Lab, Derio, Spain
- IKERBASQUE, Basque Foundation for Science, Bilbao, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Infecciosas (CIBERINFEC), Carlos III National Health Institute, Madrid, Spain
- * E-mail: (JC); (RB)
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Mohammadi B, Song F, Matamoros-Angles A, Shafiq M, Damme M, Puig B, Glatzel M, Altmeppen HC. Anchorless risk or released benefit? An updated view on the ADAM10-mediated shedding of the prion protein. Cell Tissue Res 2022; 392:215-234. [PMID: 35084572 PMCID: PMC10113312 DOI: 10.1007/s00441-022-03582-4] [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: 10/13/2021] [Accepted: 01/12/2022] [Indexed: 11/24/2022]
Abstract
The prion protein (PrP) is a broadly expressed glycoprotein linked with a multitude of (suggested) biological and pathological implications. Some of these roles seem to be due to constitutively generated proteolytic fragments of the protein. Among them is a soluble PrP form, which is released from the surface of neurons and other cell types by action of the metalloprotease ADAM10 in a process termed 'shedding'. The latter aspect is the focus of this review, which aims to provide a comprehensive overview on (i) the relevance of proteolytic processing in regulating cellular PrP functions, (ii) currently described involvement of shed PrP in neurodegenerative diseases (including prion diseases and Alzheimer's disease), (iii) shed PrP's expected roles in intercellular communication in many more (patho)physiological conditions (such as stroke, cancer or immune responses), (iv) and the need for improved research tools in respective (future) studies. Deeper mechanistic insight into roles played by PrP shedding and its resulting fragment may pave the way for improved diagnostics and future therapeutic approaches in diseases of the brain and beyond.
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Affiliation(s)
- Behnam Mohammadi
- Institute of Neuropathology, University Medical Center Hamburg-Eppendorf (UKE), Hamburg, Germany
- Working Group for Interdisciplinary Neurobiology and Immunology (INI Research), Hamburg, Germany
| | - Feizhi Song
- Institute of Neuropathology, University Medical Center Hamburg-Eppendorf (UKE), Hamburg, Germany
| | - Andreu Matamoros-Angles
- Institute of Neuropathology, University Medical Center Hamburg-Eppendorf (UKE), Hamburg, Germany
| | - Mohsin Shafiq
- Institute of Neuropathology, University Medical Center Hamburg-Eppendorf (UKE), Hamburg, Germany
| | - Markus Damme
- Institute of Biochemistry, Christian-Albrechts-University Kiel, Kiel, Germany
| | - Berta Puig
- Department of Neurology, Experimental Research in Stroke and Inflammation (ERSI), University Medical Center Hamburg-Eppendorf (UKE), Hamburg, Germany
| | - Markus Glatzel
- Institute of Neuropathology, University Medical Center Hamburg-Eppendorf (UKE), Hamburg, Germany
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8
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Espinosa JC, Marín‐Moreno A, Aguilar‐Calvo P, Torres JM. Met 166 -Glu 168 residues in human PrP β2-α2 loop account for evolutionary resistance to prion infection. Neuropathol Appl Neurobiol 2021; 47:506-518. [PMID: 33253417 PMCID: PMC8247420 DOI: 10.1111/nan.12676] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 11/06/2020] [Accepted: 11/17/2020] [Indexed: 11/30/2022]
Abstract
AIMS The amino acid sequence of prion protein (PrP) is a key determinant in the transmissibility of prion diseases. While PrP sequence is highly conserved among mammalian species, minor changes in the PrP amino acid sequence may confer alterations in the transmissibility of prion diseases. Classical bovine spongiform encephalopathy (C-BSE) is the only zoonotic prion strain reported to date causing variant Creutzfeldt-Jacob disease (vCJD) in humans, although experimental transmission points to atypical L-BSE and some classical scrapie isolates as also zoonotic. The precise molecular elements in the human PrP sequence that limit the transmissibility of prion strains such as sheep/goat scrapie or cervid chronic wasting disease (CWD) are not well known. METHODS The transmissibility of a panel of diverse prions from different species was compared in transgenic mice expressing either wild-type human PrPC (MDE-HuTg340) or a mutated human PrPC harbouring Val166 -Gln168 amino acid changes (VDQ-HuTg372) in the β2-α2 loop instead of Met166 -Glu168 wild-type variants. RESULTS VDQ-HuTg372 mice were more susceptible to prions than MDE-HuTg340 mice in a strain-dependent manner. CONCLUSIONS Met166 -Glu168 amino acid residues present in wild-type human PrPC are molecular determinants that limit the propagation of most prion strains assayed in the human PrP context.
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Affiliation(s)
| | | | - Patricia Aguilar‐Calvo
- Centro de Investigación en Sanidad Animal (INIA‐CISA)MadridSpain
- Present address:
Department of PathologyUC San DiegoLa JollaCAUSA
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9
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Reflections on Cerebellar Neuropathology in Classical Scrapie. Biomolecules 2021; 11:biom11050649. [PMID: 33924986 PMCID: PMC8146067 DOI: 10.3390/biom11050649] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Revised: 04/13/2021] [Accepted: 04/20/2021] [Indexed: 01/15/2023] Open
Abstract
In this review, the most important neuropathological changes found in the cerebella of sheep affected by classical natural scrapie are discussed. This disease is the oldest known of a group of unconventional “infections” caused by toxic prions of different origins. Scrapie is currently considered a “transmissible spongiform encephalopathy” (due to its neuropathological characteristics and its transmission), which is the paradigm of prion pathologies as well as many encephalopathies (prion-like) that present aberrant deposits of insoluble protein with neurotoxic effects due to errors in their catabolization (“misfolding protein diseases”). The study of this disease is, therefore, of great relevance. Our work data from the authors’ previous publications as well as other research in the field. The four most important types of neuropathological changes are neuron abnormalities and loss, neurogliosis, tissue vacuolization (spongiosis) and pathological or abnormal prion protein (PrP) deposits/deposition. These findings were analyzed and compared to other neuropathologies. Various aspects related to the presentation and progression of the disease, the involution of different neuronal types, the neuroglial responses and the appearance of abnormal PrP deposits are discussed. The most important points of controversy in scrapie neuropathology are presented.
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10
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Nakić N, Tran TH, Novokmet M, Andreoletti O, Lauc G, Legname G. Site-specific analysis of N-glycans from different sheep prion strains. PLoS Pathog 2021; 17:e1009232. [PMID: 33600485 PMCID: PMC7891774 DOI: 10.1371/journal.ppat.1009232] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Accepted: 12/10/2020] [Indexed: 01/23/2023] Open
Abstract
Prion diseases are a group of neurodegenerative diseases affecting a wide range of mammalian species, including humans. During the course of the disease, the abnormally folded scrapie prion protein (PrPSc) accumulates in the central nervous system where it causes neurodegeneration. In prion disorders, the diverse spectrum of illnesses exists because of the presence of different isoforms of PrPSc where they occupy distinct conformational states called strains. Strains are biochemically distinguished by a characteristic three-band immunoblot pattern, defined by differences in the occupancy of two glycosylation sites on the prion protein (PrP). Characterization of the exact N-glycan structures attached on either PrPC or PrPSc is lacking. Here we report the characterization and comparison of N-glycans from two different sheep prion strains. PrPSc from both strains was isolated from brain tissue and enzymatically digested with trypsin. By using liquid chromatography coupled to electrospray mass spectrometry, a site-specific analysis was performed. A total of 100 structures were detected on both glycosylation sites. The N-glycan profile was shown to be similar to the one on mouse PrP, however, with additional 40 structures reported. The results presented here show no major differences in glycan composition, suggesting that glycans may not be responsible for the differences in the two analyzed prion strains. To date, prion diseases remain a controversy amongst scientists. Although we know now it is the abnormal form of the prion protein (PrPSc) that causes the disease, many questions are still left unanswered. To understand the cellular mechanism of these diseases, we should first and foremost try to fully understand the prion protein itself. Even though many findings have been made regarding the structure of the protein, a large part of it is still unknown. Since the prion protein is actually a glycoprotein, to resolve its structure we need to put our focus not only on the protein part of the glycoprotein but also on the glycan structures as well. Here we compared two different sheep prion strains and although no major differences have been found between the glycan structures, this analysis may help the understanding of the role glycans have in prion diseases.
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Affiliation(s)
- Natali Nakić
- Genos Glycoscience Research Laboratory, Zagreb, Croatia.,Laboratory of Prion Biology, Department of Neuroscience, Scuola Internazionale Superiore di Studi Avanzati (SISSA), Trieste, Italy
| | - Thanh Hoa Tran
- Laboratory of Prion Biology, Department of Neuroscience, Scuola Internazionale Superiore di Studi Avanzati (SISSA), Trieste, Italy.,VNUK Institute for Research and Executive Education, The University of Danang, Da Nang, Vietnam
| | | | - Olivier Andreoletti
- UMR INRA ENVT 1225-IHAP, École Nationale Vétérinaire de Toulouse, Toulouse, France
| | - Gordan Lauc
- Genos Glycoscience Research Laboratory, Zagreb, Croatia.,Faculty of Pharmacy and Biochemistry, University of Zagreb, Zagreb, Croatia
| | - Giuseppe Legname
- Laboratory of Prion Biology, Department of Neuroscience, Scuola Internazionale Superiore di Studi Avanzati (SISSA), Trieste, Italy.,ELETTRA Sincrotrone Trieste S.C.p.A., Basovizza, Trieste, Italy
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11
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Kang HE, Bian J, Kane SJ, Kim S, Selwyn V, Crowell J, Bartz JC, Telling GC. Incomplete glycosylation during prion infection unmasks a prion protein epitope that facilitates prion detection and strain discrimination. J Biol Chem 2020; 295:10420-10433. [PMID: 32513872 PMCID: PMC7383396 DOI: 10.1074/jbc.ra120.012796] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 05/31/2020] [Indexed: 11/06/2022] Open
Abstract
The causative factors underlying conformational conversion of cellular prion protein (PrPC) into its infectious counterpart (PrPSc) during prion infection remain undetermined, in part because of a lack of monoclonal antibodies (mAbs) that can distinguish these conformational isoforms. Here we show that the anti-PrP mAb PRC7 recognizes an epitope that is shielded from detection when glycans are attached to Asn-196. We observed that whereas PrPC is predisposed to full glycosylation and is therefore refractory to PRC7 detection, prion infection leads to diminished PrPSc glycosylation at Asn-196, resulting in an unshielded PRC7 epitope that is amenable to mAb recognition upon renaturation. Detection of PRC7-reactive PrPSc in experimental and natural infections with various mouse-adapted scrapie strains and with prions causing deer and elk chronic wasting disease and transmissible mink encephalopathy uncovered that incomplete PrPSc glycosylation is a consistent feature of prion pathogenesis. We also show that interrogating the conformational properties of the PRC7 epitope affords a direct means of distinguishing different prion strains. Because the specificity of our approach for prion detection and strain discrimination relies on the extent to which N-linked glycosylation shields or unshields PrP epitopes from antibody recognition, it dispenses with the requirement for additional standard manipulations to distinguish PrPSc from PrPC, including evaluation of protease resistance. Our findings not only highlight an innovative and facile strategy for prion detection and strain differentiation, but are also consistent with a mechanism of prion replication in which structural instability of incompletely glycosylated PrP contributes to the conformational conversion of PrPC to PrPSc.
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Affiliation(s)
- Hae-Eun Kang
- Prion Research Center (PRC), the Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado
| | - Jifeng Bian
- Prion Research Center (PRC), the Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado
| | - Sarah J. Kane
- Prion Research Center (PRC), the Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado
| | - Sehun Kim
- Prion Research Center (PRC), the Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado
| | - Vanessa Selwyn
- Prion Research Center (PRC), the Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado,Program in Cell and Molecular Biology, Colorado State University, Fort Collins, Colorado
| | - Jenna Crowell
- Prion Research Center (PRC), the Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado
| | - Jason C. Bartz
- Department of Medical Microbiology and Immunology, Creighton University, Omaha, Nebraska
| | - Glenn C. Telling
- Prion Research Center (PRC), the Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado,Program in Cell and Molecular Biology, Colorado State University, Fort Collins, Colorado,For correspondence: Glenn C. Telling,
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12
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Bistaffa E, Rossi M, De Luca CMG, Cazzaniga F, Carletta O, Campagnani I, Tagliavini F, Legname G, Giaccone G, Moda F. Prion Efficiently Replicates in α-Synuclein Knockout Mice. Mol Neurobiol 2019; 56:7448-7457. [PMID: 31041657 DOI: 10.1007/s12035-019-1602-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Accepted: 04/09/2019] [Indexed: 10/26/2022]
Abstract
Prion diseases are a group of neurodegenerative disorders associated with the conformational conversion of the cellular prion protein (PrPC) into an abnormal misfolded form named PrPSc. Other than accumulating in the brain, PrPSc can bind PrPC and force it to change conformation to PrPSc. The exact mechanism which underlies the process of PrPC/PrPSc conversion still needs to be defined and many molecules or cofactors might be involved. Several studies have documented an important role of PrPC to act as receptor for abnormally folded forms of α-synuclein which are responsible of a group of diseases known as synucleinopathies. The presence of PrPC was required to promote efficient internalization and spreading of abnormal α-synuclein between cells. In this work, we have assessed whether α-synuclein exerts any role in PrPSc conversion and propagation either in vitro or in vivo. Indeed, understanding the mechanism of PrPC/PrPSc conversion and the identification of cofactors involved in this process is crucial for developing new therapeutic strategies. Our results showed that PrPSc was able to efficiently propagate in the brain of animals even in the absence of α-synuclein thus suggesting that this protein did not act as key modulator of prion propagation. Thus, α-synuclein might take part in this process but is not specifically required for sustaining prion conversion and propagation.
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Affiliation(s)
- Edoardo Bistaffa
- Unit of Neuropathology and Neurology 5, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Martina Rossi
- Department of Neuroscience, Laboratory of Prion Biology, Scuola Internazionale Superiore di Studi Avanzati (SISSA), Trieste, Italy
| | - Chiara Maria Giulia De Luca
- Unit of Neuropathology and Neurology 5, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy.,Department of Neuroscience, Laboratory of Prion Biology, Scuola Internazionale Superiore di Studi Avanzati (SISSA), Trieste, Italy
| | - Federico Cazzaniga
- Unit of Neuropathology and Neurology 5, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Olga Carletta
- Unit of Neuropathology and Neurology 5, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Ilaria Campagnani
- Unit of Neuropathology and Neurology 5, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Fabrizio Tagliavini
- Unit of Neuropathology and Neurology 5, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Giuseppe Legname
- Department of Neuroscience, Laboratory of Prion Biology, Scuola Internazionale Superiore di Studi Avanzati (SISSA), Trieste, Italy
| | - Giorgio Giaccone
- Unit of Neuropathology and Neurology 5, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Fabio Moda
- Unit of Neuropathology and Neurology 5, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy.
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13
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Martinelli AHS, Lopes FC, John EBO, Carlini CR, Ligabue-Braun R. Modulation of Disordered Proteins with a Focus on Neurodegenerative Diseases and Other Pathologies. Int J Mol Sci 2019; 20:ijms20061322. [PMID: 30875980 PMCID: PMC6471803 DOI: 10.3390/ijms20061322] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 02/03/2019] [Accepted: 02/12/2019] [Indexed: 12/15/2022] Open
Abstract
Intrinsically disordered proteins (IDPs) do not have rigid 3D structures, showing changes in their folding depending on the environment or ligands. Intrinsically disordered proteins are widely spread in eukaryotic genomes, and these proteins participate in many cell regulatory metabolism processes. Some IDPs, when aberrantly folded, can be the cause of some diseases such as Alzheimer′s, Parkinson′s, and prionic, among others. In these diseases, there are modifications in parts of the protein or in its entirety. A common conformational variation of these IDPs is misfolding and aggregation, forming, for instance, neurotoxic amyloid plaques. In this review, we discuss some IDPs that are involved in neurodegenerative diseases (such as beta amyloid, alpha synuclein, tau, and the “IDP-like” PrP), cancer (p53, c-Myc), and diabetes (amylin), focusing on the structural changes of these IDPs that are linked to such pathologies. We also present the IDP modulation mechanisms that can be explored in new strategies for drug design. Lastly, we show some candidate drugs that can be used in the future for the treatment of diseases caused by misfolded IDPs, considering that cancer therapy has more advanced research in comparison to other diseases, while also discussing recent and future developments in this area of research. Therefore, we aim to provide support to the study of IDPs and their modulation mechanisms as promising approaches to combat such severe diseases.
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Affiliation(s)
- Anne H S Martinelli
- Department of Molecular Biology and Biotechnology & Department of Biophysics, Biosciences Institute-IB, (UFRGS), Porto Alegre CEP 91501-970, RS, Brazil.
| | - Fernanda C Lopes
- Center for Biotechnology, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre CEP 91501-970, RS, Brazil.
- Graduate Program in Cell and Molecular Biology, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre CEP 91501-970, RS, Brazil.
| | - Elisa B O John
- Center for Biotechnology, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre CEP 91501-970, RS, Brazil.
- Graduate Program in Cell and Molecular Biology, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre CEP 91501-970, RS, Brazil.
| | - Célia R Carlini
- Graduate Program in Cell and Molecular Biology, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre CEP 91501-970, RS, Brazil.
- Graduate Program in Medicine and Health Sciences, Pontifícia Universidade Católica do Rio Grande do Sul (PUCRS), Porto Alegre CEP 91410-000, RS, Brazil.
- Brain Institute-InsCer, Laboratory of Neurotoxins, Pontifícia Universidade Católica do Rio Grande do Sul (PUCRS), Porto Alegre CEP 90610-000, RS, Brazil.
| | - Rodrigo Ligabue-Braun
- Department of Pharmaceutical Sciences, Universidade Federal de Ciências da Saúde de Porto Alegre (UFCSPA), Porto Alegre CEP 90050-170, RS, Brazil.
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14
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Xhima K, Nabbouh F, Hynynen K, Aubert I, Tandon A. Noninvasive delivery of an α-synuclein gene silencing vector with magnetic resonance-guided focused ultrasound. Mov Disord 2018; 33:1567-1579. [PMID: 30264465 DOI: 10.1002/mds.101] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Revised: 06/20/2018] [Accepted: 06/25/2018] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND The characteristic progression of Lewy pathology in Parkinson's disease likely involves intercellular exchange and the accumulation of misfolded α-synuclein amplified by a prion-like self-templating mechanism. Silencing of the α-synuclein gene could provide long-lasting disease-modifying benefits by reducing the requisite substrate for the spreading aggregation. OBJECTIVES As a result of the poor penetration of viral vectors across the blood-brain barrier, gene therapy for central nervous system disorders requires direct injections into the affected brain regions, and invasiveness is further increased by the need for bilateral delivery to multiple brain regions. Here we test a noninvasive approach by combining low-intensity magnetic resonance-guided focused ultrasound and intravenous microbubbles that can transiently increase the access of brain impermeant therapeutic macromolecules to targeted brain regions. METHODS Transgenic mice expressing human α-synuclein were subjected to magnetic resonance-guided focused ultrasound targeted to 4 brain regions (hippocampus, substantia nigra, olfactory bulb, and dorsal motor nucleus) in tandem with intravenous microbubbles and an adeno-associated virus serotype 9 vector bearing a short hairpin RNA sequence targeting the α-synuclein gene. RESULTS One month following treatment, α-synuclein immunoreactivity was decreased in targeted brain regions, whereas other neuronal markers such as synaptophysin or tyrosine hydroxylase were unchanged, and cell death and glial activation remained at basal levels. CONCLUSIONS These results demonstrate that magnetic resonance-guided focused ultrasound can effectively, noninvasively, and simultaneously deliver viral vectors targeting α-synuclein to multiple brain areas. Importantly, this approach may be useful to alter the progression of Lewy pathology along selected neuronal pathways, particularly as prodromal PD markers improve early diagnoses. © 2018 International Parkinson and Movement Disorder Society.
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Affiliation(s)
- Kristiana Xhima
- Sunnybrook Research Institute, Toronto, Ontario, Canada.,Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Fadl Nabbouh
- Tanz Centre for Research in Neurodegenerative Diseases, Toronto, Ontario, Canada
| | - Kullervo Hynynen
- Sunnybrook Research Institute, Toronto, Ontario, Canada.,Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
| | - Isabelle Aubert
- Sunnybrook Research Institute, Toronto, Ontario, Canada.,Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Anurag Tandon
- Tanz Centre for Research in Neurodegenerative Diseases, Toronto, Ontario, Canada.,Department of Medicine, University of Toronto, Toronto, Ontario, Canada
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15
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Abstract
The cellular prion protein, PrPC, is a small, cell surface glycoprotein with a function that is currently somewhat ill defined. It is also the key molecule involved in the family of neurodegenerative disorders called transmissible spongiform encephalopathies, which are also known as prion diseases. The misfolding of PrPC to a conformationally altered isoform, designated PrPTSE, is the main molecular process involved in pathogenesis and appears to precede many other pathologic and clinical manifestations of disease, including neuronal loss, astrogliosis, and cognitive loss. PrPTSE is also believed to be the major component of the infectious "prion," the agent responsible for disease transmission, and preparations of this protein can cause prion disease when inoculated into a naïve host. Thus, understanding the biochemical and biophysical properties of both PrPC and PrPTSE, and ultimately the mechanisms of their interconversion, is critical if we are to understand prion disease biology. Although entire books could be devoted to research pertaining to the protein, herein we briefly review the state of knowledge of prion biochemistry, including consideration of prion protein structure, function, misfolding, and dysfunction.
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Affiliation(s)
- Andrew C Gill
- School of Chemistry, Joseph Banks Laboratories, University of Lincoln, Lincoln, United Kingdom; Division of Neurobiology, The Roslin Institute and Royal (Dick) School of Veterinary Sciences, University of Edinburgh, Edinburgh, United Kingdom.
| | - Andrew R Castle
- Division of Neurobiology, The Roslin Institute and Royal (Dick) School of Veterinary Sciences, University of Edinburgh, Edinburgh, United Kingdom
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16
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Sharma S, Young RJ, Chen J, Chen X, Oh EC, Schiller MR. Minimotifs dysfunction is pervasive in neurodegenerative disorders. ALZHEIMER'S & DEMENTIA (NEW YORK, N. Y.) 2018; 4:414-432. [PMID: 30225339 PMCID: PMC6139474 DOI: 10.1016/j.trci.2018.06.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Minimotifs are modular contiguous peptide sequences in proteins that are important for posttranslational modifications, binding to other molecules, and trafficking to specific subcellular compartments. Some molecular functions of proteins in cellular pathways can be predicted from minimotif consensus sequences identified through experimentation. While a role for minimotifs in regulating signal transduction and gene regulation during disease pathogenesis (such as infectious diseases and cancer) is established, the therapeutic use of minimotif mimetic drugs is limited. In this review, we discuss a general theme identifying a pervasive role of minimotifs in the pathomechanism of neurodegenerative diseases. Beyond their longstanding history in the genetics of familial neurodegeneration, minimotifs are also major players in neurotoxic protein aggregation, aberrant protein trafficking, and epigenetic regulation. Generalizing the importance of minimotifs in neurodegenerative diseases offers a new perspective for the future study of neurodegenerative mechanisms and the investigation of new therapeutics.
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Affiliation(s)
- Surbhi Sharma
- Nevada Institute of Personalized Medicine, Las Vegas, NV, USA
- School of Life Sciences, Las Vegas, NV, USA
| | - Richard J. Young
- Nevada Institute of Personalized Medicine, Las Vegas, NV, USA
- School of Life Sciences, Las Vegas, NV, USA
| | - Jingchun Chen
- Nevada Institute of Personalized Medicine, Las Vegas, NV, USA
| | - Xiangning Chen
- Nevada Institute of Personalized Medicine, Las Vegas, NV, USA
- Department of Psychology, Las Vegas, NV, USA
| | - Edwin C. Oh
- Nevada Institute of Personalized Medicine, Las Vegas, NV, USA
- School of Medicine, Las Vegas, NV, USA
| | - Martin R. Schiller
- Nevada Institute of Personalized Medicine, Las Vegas, NV, USA
- School of Life Sciences, Las Vegas, NV, USA
- School of Medicine, Las Vegas, NV, USA
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17
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NLRs as Helpline in the Brain: Mechanisms and Therapeutic Implications. Mol Neurobiol 2018; 55:8154-8178. [DOI: 10.1007/s12035-018-0957-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Accepted: 02/12/2018] [Indexed: 12/13/2022]
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18
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Knock E, Matsuzaki S, Takamura H, Satoh K, Rooke G, Han K, Zhang H, Staniszewski A, Katayama T, Arancio O, Fraser PE. SUMO1 impact on Alzheimer disease pathology in an amyloid-depositing mouse model. Neurobiol Dis 2018; 110:154-165. [DOI: 10.1016/j.nbd.2017.11.015] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Revised: 11/20/2017] [Accepted: 11/29/2017] [Indexed: 12/27/2022] Open
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19
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Longhena F, Spano P, Bellucci A. Targeting of Disordered Proteins by Small Molecules in Neurodegenerative Diseases. Handb Exp Pharmacol 2018; 245:85-110. [PMID: 28965171 DOI: 10.1007/164_2017_60] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The formation of protein aggregates and inclusions in the brain and spinal cord is a common neuropathological feature of a number of neurodegenerative diseases including Alzheimer's disease (AD), Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS), and many others. These are commonly referred as neurodegenerative proteinopathies or protein-misfolding diseases. The main characteristic of protein aggregates in these disorders is the fact that they are enriched in amyloid fibrils. Since protein aggregation is considered to play a central role for the onset of neurodegenerative proteinopathies, research is ongoing to develop strategies aimed at preventing or removing protein aggregation in the brain of affected patients. Numerous studies have shown that small molecule-based approaches may be potentially the most promising for halting protein aggregation in neurodegenerative diseases. Indeed, several of these compounds have been found to interact with intrinsically disordered proteins and promote their clearing in experimental models. This notwithstanding, at present small molecule inhibitors still awaits achievements for clinical translation. Hopefully, if we determine whether the formation of insoluble inclusions is effectively neurotoxic and find a valid biomarker to assess their protein aggregation-inhibitory activity in the human central nervous system, the use of small molecule inhibitors will be considered as a cure for neurodegenerative protein-misfolding diseases.
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Affiliation(s)
- Francesca Longhena
- Division of Pharmacology, Department of Molecular and Translational Medicine, University of Brescia, Viale Europa No. 11, Brescia, 25123, Italy
| | - PierFranco Spano
- Division of Pharmacology, Department of Molecular and Translational Medicine, University of Brescia, Viale Europa No. 11, Brescia, 25123, Italy
| | - Arianna Bellucci
- Division of Pharmacology, Department of Molecular and Translational Medicine, University of Brescia, Viale Europa No. 11, Brescia, 25123, Italy.
- Laboratory of Personalized and Preventive Medicine, University of Brescia, Brescia, Italy.
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20
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Watts JC, Prusiner SB. Experimental Models of Inherited PrP Prion Diseases. Cold Spring Harb Perspect Med 2017; 7:cshperspect.a027151. [PMID: 28096244 DOI: 10.1101/cshperspect.a027151] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The inherited prion protein (PrP) prion disorders, which include familial Creutzfeldt-Jakob disease, Gerstmann-Sträussler-Scheinker disease, and fatal familial insomnia, constitute ∼10%-15% of all PrP prion disease cases in humans. Attempts to generate animal models of these disorders using transgenic mice expressing mutant PrP have produced variable results. Although many lines of mice develop spontaneous signs of neurological illness with accompanying prion disease-specific neuropathological changes, others do not. Furthermore, demonstrating the presence of protease-resistant PrP species and prion infectivity-two of the hallmarks of the PrP prion disorders-in the brains of spontaneously sick mice has proven particularly challenging. Here, we review the progress that has been made toward developing accurate mouse models of the inherited PrP prion disorders.
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Affiliation(s)
- Joel C Watts
- Tanz Centre for Research in Neurodegenerative Diseases and Department of Biochemistry, University of Toronto, Toronto, Ontario M5T 2S8, Canada
| | - Stanley B Prusiner
- Institute for Neurodegenerative Diseases, Departments of Neurology and Biochemistry and Biophysics, Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, California 94143
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21
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Diack AB, Alibhai JD, Manson JC. Gene Targeted Transgenic Mouse Models in Prion Research. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2017; 150:157-179. [PMID: 28838660 DOI: 10.1016/bs.pmbts.2017.06.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The production of transgenic mice expressing different forms of the prion protein (PrP) or devoid of PrP has enabled researchers to study the role of PrP in the infectious process of a prion disease and its normal function in the healthy individual. A wide range of transgenic models have been produced ranging from PrP null mice, normal expression levels to overexpression models, models expressing different species of the Prnp gene and different mutations and polymorphisms within the gene. Using this range of transgenic models has allowed us to define the influence of PrP expression on disease susceptibility and transmission, assess zoonotic potential, define strains of human prion diseases, elucidate the function of PrP, and start to unravel the mechanisms involved in chronic neurodegeneration. This chapter focuses mainly on the use of the gene targeted transgenic models and summarizes the ways in which they have allowed us to study the role of PrP in prion disease and the insights they have provided into the mechanisms of neurodegenerative diseases.
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Affiliation(s)
- Abigail B Diack
- The Roslin Institute & R(D)SVS, University of Edinburgh, Easter Bush, United Kingdom.
| | - James D Alibhai
- The National CJD Research and Surveillance Unit, Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Jean C Manson
- The Roslin Institute & R(D)SVS, University of Edinburgh, Easter Bush, United Kingdom
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22
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Legname G, Moda F. The Prion Concept and Synthetic Prions. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2017; 150:147-156. [PMID: 28838659 DOI: 10.1016/bs.pmbts.2017.06.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/23/2023]
Abstract
Transmissible spongiform encephalopathies or prion diseases are a group of fatal neurodegenerative diseases caused by unconventional infectious agents, known as prions (PrPSc). Prions derive from a conformational conversion of the normally folded prion protein (PrPC), which acquires pathological and infectious features. Moreover, PrPSc is able to transmit the pathological conformation to PrPC through a mechanism that is still not well understood. The generation of synthetic prions, which behave like natural prions, is of fundamental importance to study the process of PrPC conversion and to assess the efficacy of therapeutic strategies to interfere with this process. Moreover, the ability of synthetic prions to induce pathology in animals confirms that the pathological properties of the prion strains are all enciphered in abnormal conformations, characterizing these infectious agents.
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Affiliation(s)
- Giuseppe Legname
- Scuola Internazionale Superiore di Studi Avanzati (SISSA), Trieste, Italy.
| | - Fabio Moda
- IRCCS Foundation Carlo Besta Neurological Institute, Milan, Italy.
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23
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Cheng CJ, Koldsø H, Van der Kamp MW, Schiøtt B, Daggett V. Simulations of membrane-bound diglycosylated human prion protein reveal potential protective mechanisms against misfolding. J Neurochem 2017; 142:171-182. [PMID: 28407243 DOI: 10.1111/jnc.14044] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Revised: 03/28/2017] [Accepted: 03/28/2017] [Indexed: 01/06/2023]
Abstract
Prion diseases are associated with the misfolding of the prion protein (PrP) from its normal cellular form (PrPC ) to its infectious scrapie form (PrPSc ). Post-translational modifications in PrP in vivo can play an important role in modulating the process of misfolding. To gain more insight into the effects of post-translational modifications in PrP structure and dynamics and to test the hypothesis that such modifications can interact with the protein, we have performed molecular dynamics simulations of diglycosylated human PrPC bound to a lipid bilayer via a glycophosphatidylinositol anchor. Multiple simulations were performed at three different pH ranges to explore pH effects on structure and dynamics. In contrast to simulations of protein-only PrPC , no large effects were observed upon lowering the pH of the system. The protein tilted toward the membrane surface in all of the simulations and the putative PrPSc oligomerization sites became inaccessible, thereby offering a possible protective mechanism against PrPSc -induced misfolding of PrPC .
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Affiliation(s)
- Chin Jung Cheng
- Department of Bioengineering, University of Washington, Seattle, Washington, USA
| | - Heidi Koldsø
- Department of Bioengineering, University of Washington, Seattle, Washington, USA.,Department of Chemistry, inSPIN and iNANO Centers, Aarhus University, Aarhus C, Denmark
| | - Marc W Van der Kamp
- Department of Bioengineering, University of Washington, Seattle, Washington, USA
| | - Birgit Schiøtt
- Department of Chemistry, inSPIN and iNANO Centers, Aarhus University, Aarhus C, Denmark
| | - Valerie Daggett
- Department of Bioengineering, University of Washington, Seattle, Washington, USA
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24
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Ragagnin A, Ezpeleta J, Guillemain A, Boudet-Devaud F, Haeberlé AM, Demais V, Vidal C, Demuth S, Béringue V, Kellermann O, Schneider B, Grant NJ, Bailly Y. Cerebellar compartmentation of prion pathogenesis. Brain Pathol 2017; 28:240-263. [PMID: 28268246 DOI: 10.1111/bpa.12503] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Accepted: 03/01/2017] [Indexed: 02/06/2023] Open
Abstract
In prion diseases, the brain lesion profile is influenced by the prion "strain" properties, the invasion route to the brain, and still unknown host cell-specific parameters. To gain insight into those endogenous factors, we analyzed the histopathological alterations induced by distinct prion strains in the mouse cerebellum. We show that 22L and ME7 scrapie prion proteins (PrP22L , PrPME7 ), but not bovine spongiform encephalopathy PrP6PB1 , accumulate in a reproducible parasagittal banding pattern in the cerebellar cortex of infected mice. Such banding pattern of PrP22L aggregation did not depend on the neuroinvasion route, but coincided with the parasagittal compartmentation of the cerebellum mostly defined by the expression of zebrins, such as aldolase C and the excitatory amino acid transporter 4, in Purkinje cells. We provide evidence that Purkinje cells display a differential, subtype-specific vulnerability to 22L prions with zebrin-expressing Purkinje cells being more resistant to prion toxicity, while in stripes where PrP22L accumulated most zebrin-deficient Purkinje cells are lost and spongiosis accentuated. In addition, in PrP22L stripes, enhanced reactive astrocyte processes associated with microglia activation support interdependent events between the topographic pattern of Purkinje cell death, reactive gliosis and PrP22L accumulation. Finally, we find that in preclinically-ill mice prion infection promotes at the membrane of astrocytes enveloping Purkinje cell excitatory synapses, upregulation of tumor necrosis factor-α receptor type 1 (TNFR1), a key mediator of the neuroinflammation process. These overall data show that Purkinje cell sensitivity to prion insult is locally restricted by the parasagittal compartmentation of the cerebellum, and that perisynaptic astrocytes may contribute to prion pathogenesis through prion-induced TNFR1 upregulation.
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Affiliation(s)
- Audrey Ragagnin
- Cytologie et Cytopathologie Neuronales, Institut des Neurosciences Cellulaires & Intégratives, CNRS UPR 3212, Strasbourg, France
| | - Juliette Ezpeleta
- INSERM UMR-S1124, Cellules Souches, Signalisation et Prions, Université Paris Descartes, Paris, France
| | - Aurélie Guillemain
- Cytologie et Cytopathologie Neuronales, Institut des Neurosciences Cellulaires & Intégratives, CNRS UPR 3212, Strasbourg, France
| | - François Boudet-Devaud
- INSERM UMR-S1124, Cellules Souches, Signalisation et Prions, Université Paris Descartes, Paris, France
| | - Anne-Marie Haeberlé
- Cytologie et Cytopathologie Neuronales, Institut des Neurosciences Cellulaires & Intégratives, CNRS UPR 3212, Strasbourg, France
| | - Valérie Demais
- Plateforme Imagerie In Vitro, CNRS UPS-3156, Université de Strasbourg, Strasbourg, France
| | | | - Stanislas Demuth
- Cytologie et Cytopathologie Neuronales, Institut des Neurosciences Cellulaires & Intégratives, CNRS UPR 3212, Strasbourg, France
| | | | - Odile Kellermann
- INSERM UMR-S1124, Cellules Souches, Signalisation et Prions, Université Paris Descartes, Paris, France
| | - Benoit Schneider
- INSERM UMR-S1124, Cellules Souches, Signalisation et Prions, Université Paris Descartes, Paris, France
| | - Nancy J Grant
- Cytologie et Cytopathologie Neuronales, Institut des Neurosciences Cellulaires & Intégratives, CNRS UPR 3212, Strasbourg, France
| | - Yannick Bailly
- Cytologie et Cytopathologie Neuronales, Institut des Neurosciences Cellulaires & Intégratives, CNRS UPR 3212, Strasbourg, France
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Aguilar-Calvo P, Xiao X, Bett C, Eraña H, Soldau K, Castilla J, Nilsson KPR, Surewicz WK, Sigurdson CJ. Post-translational modifications in PrP expand the conformational diversity of prions in vivo. Sci Rep 2017; 7:43295. [PMID: 28272426 PMCID: PMC5341109 DOI: 10.1038/srep43295] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2016] [Accepted: 01/23/2017] [Indexed: 12/02/2022] Open
Abstract
Misfolded prion protein aggregates (PrPSc) show remarkable structural diversity and are associated with highly variable disease phenotypes. Similarly, other proteins, including amyloid-β, tau, α-synuclein, and serum amyloid A, misfold into distinct conformers linked to different clinical diseases through poorly understood mechanisms. Here we use mice expressing glycophosphatidylinositol (GPI)-anchorless prion protein, PrPC, together with hydrogen-deuterium exchange coupled with mass spectrometry (HXMS) and a battery of biochemical and biophysical tools to investigate how post-translational modifications impact the aggregated prion protein properties and disease phenotype. Four GPI-anchorless prion strains caused a nearly identical clinical and pathological disease phenotype, yet maintained their structural diversity in the anchorless state. HXMS studies revealed that GPI-anchorless PrPSc is characterized by substantially higher protection against hydrogen/deuterium exchange in the C-terminal region near the N-glycan sites, suggesting this region had become more ordered in the anchorless state. For one strain, passage of GPI-anchorless prions into wild type mice led to the emergence of a novel strain with a unique biochemical and phenotypic signature. For the new strain, histidine hydrogen-deuterium mass spectrometry revealed altered packing arrangements of β-sheets that encompass residues 139 and 186 of PrPSc. These findings show how variation in post-translational modifications may explain the emergence of new protein conformations in vivo and also provide a basis for understanding how the misfolded protein structure impacts the disease.
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Affiliation(s)
| | - Xiangzhu Xiao
- Department of Physiology and Biophysics, Case Western Reserve University, Cleveland, OH 44116, USA
| | - Cyrus Bett
- Departments of Pathology and Medicine, UC San Diego, La Jolla, CA 92093-0612, USA
| | - Hasier Eraña
- CIC bioGUNE, Parque Tecnológico de Bizkaia, Ed. 800, Derio 48160, Spain
| | - Katrin Soldau
- Departments of Pathology and Medicine, UC San Diego, La Jolla, CA 92093-0612, USA
| | - Joaquin Castilla
- CIC bioGUNE, Parque Tecnológico de Bizkaia, Ed. 800, Derio 48160, Spain.,IKERBASQUE, Basque Foundation for Science, 48013 Bilbao, Spain
| | - K Peter R Nilsson
- Department of Physics, Chemistry, and Biology, Linköping University, Linköping 581 83, Sweden
| | - Witold K Surewicz
- Department of Physiology and Biophysics, Case Western Reserve University, Cleveland, OH 44116, USA
| | - Christina J Sigurdson
- Departments of Pathology and Medicine, UC San Diego, La Jolla, CA 92093-0612, USA.,Department of Pathology, Immunology, and Microbiology, UC Davis, Davis, CA 95616, USA
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Divergent prion strain evolution driven by PrP C expression level in transgenic mice. Nat Commun 2017; 8:14170. [PMID: 28112164 PMCID: PMC5264111 DOI: 10.1038/ncomms14170] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Accepted: 12/06/2016] [Indexed: 12/31/2022] Open
Abstract
Prions induce a fatal neurodegenerative disease in infected host brain based on the refolding and aggregation of the host-encoded prion protein PrPC into PrPSc. Structurally distinct PrPSc conformers can give rise to multiple prion strains. Constrained interactions between PrPC and different PrPSc strains can in turn lead to certain PrPSc (sub)populations being selected for cross-species transmission, or even produce mutation-like events. By contrast, prion strains are generally conserved when transmitted within the same species, or to transgenic mice expressing homologous PrPC. Here, we compare the strain properties of a representative sheep scrapie isolate transmitted to a panel of transgenic mouse lines expressing varying levels of homologous PrPC. While breeding true in mice expressing PrPC at near physiological levels, scrapie prions evolve consistently towards different strain components in mice beyond a certain threshold of PrPC overexpression. Our results support the view that PrPC gene dosage can influence prion evolution on homotypic transmission. PrPC protein plays a key role in prion transmission across species. Here, the authors compare transmission of a representative scrapie isolate to transgenic mice expressing variable levels of the same Prnp allele as the donor sheep, and find divergent strain propagation regulated by PrPC gene dosage.
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27
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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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28
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Guinea Pig Prion Protein Supports Rapid Propagation of Bovine Spongiform Encephalopathy and Variant Creutzfeldt-Jakob Disease Prions. J Virol 2016; 90:9558-9569. [PMID: 27440899 DOI: 10.1128/jvi.01106-16] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Accepted: 07/14/2016] [Indexed: 11/20/2022] Open
Abstract
The biochemical and neuropathological properties of bovine spongiform encephalopathy (BSE) and variant Creutzfeldt-Jakob disease (vCJD) prions are faithfully maintained upon transmission to guinea pigs. However, primary and secondary transmissions of BSE and vCJD in guinea pigs result in long incubation periods of ∼450 and ∼350 days, respectively. To determine if the incubation periods of BSE and vCJD prions could be shortened, we generated transgenic (Tg) mice expressing guinea pig prion protein (GPPrP). Inoculation of Tg(GPPrP) mice with BSE and vCJD prions resulted in mean incubation periods of 210 and 199 days, respectively, which shortened to 137 and 122 days upon serial transmission. In contrast, three different isolates of sporadic CJD prions failed to transmit disease to Tg(GPPrP) mice. Many of the strain-specified biochemical and neuropathological properties of BSE and vCJD prions, including the presence of type 2 protease-resistant PrPSc, were preserved upon propagation in Tg(GPPrP) mice. Structural modeling revealed that two residues near the N-terminal region of α-helix 1 in GPPrP might mediate its susceptibility to BSE and vCJD prions. Our results demonstrate that expression of GPPrP in Tg mice supports the rapid propagation of BSE and vCJD prions and suggest that Tg(GPPrP) mice may serve as a useful paradigm for bioassaying these prion isolates. IMPORTANCE Variant Creutzfeldt-Jakob disease (vCJD) and bovine spongiform encephalopathy (BSE) prions are two of the prion strains most relevant to human health. However, propagating these strains in mice expressing human or bovine prion protein has been difficult because of prolonged incubation periods or inefficient transmission. Here, we show that transgenic mice expressing guinea pig prion protein are fully susceptible to vCJD and BSE prions but not to sporadic CJD prions. Our results suggest that the guinea pig prion protein is a better, more rapid substrate than either bovine or human prion protein for propagating BSE and vCJD prions.
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Moudjou M, Chapuis J, Mekrouti M, Reine F, Herzog L, Sibille P, Laude H, Vilette D, Andréoletti O, Rezaei H, Dron M, Béringue V. Glycoform-independent prion conversion by highly efficient, cell-based, protein misfolding cyclic amplification. Sci Rep 2016; 6:29116. [PMID: 27384922 PMCID: PMC4935985 DOI: 10.1038/srep29116] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Accepted: 06/15/2016] [Indexed: 11/15/2022] Open
Abstract
Prions are formed of misfolded assemblies (PrPSc) of the variably N-glycosylated cellular prion protein (PrPC). In infected species, prions replicate by seeding the conversion and polymerization of host PrPC. Distinct prion strains can be recognized, exhibiting defined PrPSc biochemical properties such as the glycotype and specific biological traits. While strain information is encoded within the conformation of PrPSc assemblies, the storage of the structural information and the molecular requirements for self-perpetuation remain uncertain. Here, we investigated the specific role of PrPC glycosylation status. First, we developed an efficient protein misfolding cyclic amplification method using cells expressing the PrPC species of interest as substrate. Applying the technique to PrPC glycosylation mutants expressing cells revealed that neither PrPC nor PrPSc glycoform stoichiometry was instrumental to PrPSc formation and strainness perpetuation. Our study supports the view that strain properties, including PrPSc glycotype are enciphered within PrPSc structural backbone, not in the attached glycans.
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Affiliation(s)
- Mohammed Moudjou
- VIM, INRA, Université Paris-Saclay, 78350, Jouy-en-Josas, France
| | - Jérôme Chapuis
- VIM, INRA, Université Paris-Saclay, 78350, Jouy-en-Josas, France
| | - Mériem Mekrouti
- VIM, INRA, Université Paris-Saclay, 78350, Jouy-en-Josas, France
| | - Fabienne Reine
- VIM, INRA, Université Paris-Saclay, 78350, Jouy-en-Josas, France
| | - Laetitia Herzog
- VIM, INRA, Université Paris-Saclay, 78350, Jouy-en-Josas, France
| | - Pierre Sibille
- VIM, INRA, Université Paris-Saclay, 78350, Jouy-en-Josas, France
| | - Hubert Laude
- VIM, INRA, Université Paris-Saclay, 78350, Jouy-en-Josas, France
| | - Didier Vilette
- VIM, INRA, Université Paris-Saclay, 78350, Jouy-en-Josas, France.,IHAP, INRA, Ecole Nationale Vétérinaire de Toulouse, 31000, Toulouse, France
| | - Olivier Andréoletti
- IHAP, INRA, Ecole Nationale Vétérinaire de Toulouse, 31000, Toulouse, France
| | - Human Rezaei
- VIM, INRA, Université Paris-Saclay, 78350, Jouy-en-Josas, France
| | - Michel Dron
- VIM, INRA, Université Paris-Saclay, 78350, Jouy-en-Josas, France
| | - Vincent Béringue
- VIM, INRA, Université Paris-Saclay, 78350, Jouy-en-Josas, France
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30
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Hu PP, Morales R, Duran-Aniotz C, Moreno-Gonzalez I, Khan U, Soto C. Role of Prion Replication in the Strain-dependent Brain Regional Distribution of Prions. J Biol Chem 2016; 291:12880-12887. [PMID: 27056328 DOI: 10.1074/jbc.m115.681791] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Indexed: 01/30/2023] Open
Abstract
One intriguing feature of prion diseases is their strain variation. Prion strains are differentiated by the clinical consequences they generate in the host, their biochemical properties, and their potential to infect other animal species. The selective targeting of these agents to specific brain structures have been extensively used to characterize prion strains. However, the molecular basis dictating strain-specific neurotropism are still elusive. In this study, isolated brain structures from animals infected with four hamster prion strains (HY, DY, 139H, and SSLOW) were analyzed for their content of protease-resistant PrP(Sc) Our data show that these strains have different profiles of PrP deposition along the brain. These patterns of accumulation, which were independent of regional PrP(C) production, were not reproduced by in vitro replication when different brain regions were used as substrate for the misfolding-amplification reaction. On the contrary, our results show that in vitro replication efficiency depended exclusively on the amount of PrP(C) present in each part of the brain. Our results suggest that the variable regional distribution of PrP(Sc) in distinct strains is not determined by differences on prion formation, but on other factors or cellular pathways. Our findings may contribute to understand the molecular mechanisms of prion pathogenesis and strain diversity.
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Affiliation(s)
- Ping Ping Hu
- From the Mitchell Center for Alzheimer's Disease and Related Brain Disorders, Department of Neurology, University of Texas Houston Medical School, Houston, Texas 77030,; Innovative Drug Research Centre, Chongqing University, Chongqing 401331, China, and
| | - Rodrigo Morales
- From the Mitchell Center for Alzheimer's Disease and Related Brain Disorders, Department of Neurology, University of Texas Houston Medical School, Houston, Texas 77030
| | - Claudia Duran-Aniotz
- From the Mitchell Center for Alzheimer's Disease and Related Brain Disorders, Department of Neurology, University of Texas Houston Medical School, Houston, Texas 77030,; Universidad de los Andes, Facultad de Medicina, Av. San Carlos de Apoquindo 2200, Las Condes, Santiago, Chile
| | - Ines Moreno-Gonzalez
- From the Mitchell Center for Alzheimer's Disease and Related Brain Disorders, Department of Neurology, University of Texas Houston Medical School, Houston, Texas 77030
| | - Uffaf Khan
- From the Mitchell Center for Alzheimer's Disease and Related Brain Disorders, Department of Neurology, University of Texas Houston Medical School, Houston, Texas 77030
| | - Claudio Soto
- From the Mitchell Center for Alzheimer's Disease and Related Brain Disorders, Department of Neurology, University of Texas Houston Medical School, Houston, Texas 77030,; Universidad de los Andes, Facultad de Medicina, Av. San Carlos de Apoquindo 2200, Las Condes, Santiago, Chile.
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31
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Guo BB, Bellingham SA, Hill AF. Stimulating the Release of Exosomes Increases the Intercellular Transfer of Prions. J Biol Chem 2016; 291:5128-37. [PMID: 26769968 DOI: 10.1074/jbc.m115.684258] [Citation(s) in RCA: 102] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Indexed: 01/20/2023] Open
Abstract
Exosomes are small extracellular vesicles released by cells and play important roles in intercellular communication and pathogen transfer. Exosomes have been implicated in several neurodegenerative diseases, including prion disease and Alzheimer disease. Prion disease arises upon misfolding of the normal cellular prion protein, PrP(C), into the disease-associated isoform, PrP(Sc). The disease has a unique transmissible etiology, and exosomes represent a novel and efficient method for prion transmission. The precise mechanism by which prions are transmitted from cell to cell remains to be fully elucidated, although three hypotheses have been proposed: direct cell-cell contact, tunneling nanotubes, and exosomes. Given the reported presence of exosomes in biological fluids and in the lipid and nucleic acid contents of exosomes, these vesicles represent an ideal mechanism for encapsulating prions and potential cofactors to facilitate prion transmission. This study investigates the relationship between exosome release and intercellular prion dissemination. Stimulation of exosome release through treatment with an ionophore, monensin, revealed a corresponding increase in intercellular transfer of prion infectivity. Conversely, inhibition of exosome release using GW4869 to target the neutral sphingomyelinase pathway induced a decrease in intercellular prion transmission. Further examination of the effect of monensin on PrP conversion revealed that monensin also alters the conformational stability of PrP(C), leading to increased generation of proteinase K-resistant prion protein. The findings presented here provide support for a positive relationship between exosome release and intercellular transfer of prion infectivity, highlighting an integral role for exosomes in facilitating the unique transmissible nature of prions.
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Affiliation(s)
- Belinda B Guo
- From the Department of Biochemistry and Molecular Biology and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Melbourne, Victoria 3010, Australia and
| | - Shayne A Bellingham
- From the Department of Biochemistry and Molecular Biology and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Melbourne, Victoria 3010, Australia and
| | - Andrew F Hill
- From the Department of Biochemistry and Molecular Biology and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Melbourne, Victoria 3010, Australia and the Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria 3086, Australia
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32
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Insights into Mechanisms of Chronic Neurodegeneration. Int J Mol Sci 2016; 17:ijms17010082. [PMID: 26771599 PMCID: PMC4730326 DOI: 10.3390/ijms17010082] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Revised: 12/22/2015] [Accepted: 12/23/2015] [Indexed: 12/03/2022] Open
Abstract
Chronic neurodegenerative diseases such as Alzheimer’s disease (AD), Parkinson’s disease (PD), and prion diseases are characterised by the accumulation of abnormal conformers of a host encoded protein in the central nervous system. The process leading to neurodegeneration is still poorly defined and thus development of early intervention strategies is challenging. Unique amongst these diseases are Transmissible Spongiform Encephalopathies (TSEs) or prion diseases, which have the ability to transmit between individuals. The infectious nature of these diseases has permitted in vivo and in vitro modelling of the time course of the disease process in a highly reproducible manner, thus early events can be defined. Recent evidence has demonstrated that the cell-to-cell spread of protein aggregates by a “prion-like mechanism” is common among the protein misfolding diseases. Thus, the TSE models may provide insights into disease mechanisms and testable hypotheses for disease intervention, applicable to a number of these chronic neurodegenerative diseases.
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33
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Zacchi LF, Schulz BL. N-glycoprotein macroheterogeneity: biological implications and proteomic characterization. Glycoconj J 2015; 33:359-76. [DOI: 10.1007/s10719-015-9641-3] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Revised: 11/04/2015] [Accepted: 11/20/2015] [Indexed: 10/22/2022]
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Race B, Phillips K, Meade-White K, Striebel J, Chesebro B. Increased infectivity of anchorless mouse scrapie prions in transgenic mice overexpressing human prion protein. J Virol 2015; 89:6022-32. [PMID: 25810548 PMCID: PMC4442444 DOI: 10.1128/jvi.00362-15] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Accepted: 03/18/2015] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED Prion protein (PrP) is found in all mammals, mostly as a glycoprotein anchored to the plasma membrane by a C-terminal glycosylphosphatidylinositol (GPI) linkage. Following prion infection, host protease-sensitive prion protein (PrPsen or PrPC) is converted into an abnormal, disease-associated, protease-resistant form (PrPres). Biochemical characteristics, such as the PrP amino acid sequence, and posttranslational modifications, such as glycosylation and GPI anchoring, can affect the transmissibility of prions as well as the biochemical properties of the PrPres generated. Previous in vivo studies on the effects of GPI anchoring on prion infectivity have not examined cross-species transmission. In this study, we tested the effect of lack of GPI anchoring on a species barrier model using mice expressing human PrP. In this model, anchorless 22L prions derived from tg44 mice were more infectious than 22L prions derived from C57BL/10 mice when tested in tg66 transgenic mice, which expressed wild-type anchored human PrP at 8- to 16-fold above normal. Thus, the lack of the GPI anchor on the PrPres from tg44 mice appeared to reduce the effect of the mouse-human PrP species barrier. In contrast, neither source of prions induced disease in tgRM transgenic mice, which expressed human PrP at 2- to 4-fold above normal. IMPORTANCE Prion protein (PrP) is found in all mammals, usually attached to cells by an anchor molecule called GPI. Following prion infection, PrP is converted into a disease-associated form (PrPres). While most prion diseases are species specific, this finding is not consistent, and species barriers differ in strength. The amino acid sequence of PrP varies among species, and this variability affects prion species barriers. However, other PrP modifications, including glycosylation and GPI anchoring, may also influence cross-species infectivity. We studied the effect of PrP GPI anchoring using a mouse-to-human species barrier model. Experiments showed that prions produced by mice expressing only anchorless PrP were more infectious than prions produced in mice expressing anchored PrP. Thus, the lack of the GPI anchor on prions reduced the effect of the mouse-human species barrier. Our results suggest that prion diseases that produce higher levels of anchorless PrP may pose an increased risk for cross-species infection.
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Affiliation(s)
- Brent Race
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, USA
| | - Katie Phillips
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, USA
| | - Kimberly Meade-White
- Rocky Mountain Veterinary Branch, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, USA
| | - James Striebel
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, USA
| | - Bruce Chesebro
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, USA
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SUMO1 Affects Synaptic Function, Spine Density and Memory. Sci Rep 2015; 5:10730. [PMID: 26022678 PMCID: PMC4650663 DOI: 10.1038/srep10730] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Accepted: 04/17/2015] [Indexed: 01/19/2023] Open
Abstract
Small ubiquitin-like modifier-1 (SUMO1) plays a number of roles in cellular events and recent evidence has given momentum for its contributions to neuronal development and function. Here, we have generated a SUMO1 transgenic mouse model with exclusive overexpression in neurons in an effort to identify in vivo conjugation targets and the functional consequences of their SUMOylation. A high-expressing line was examined which displayed elevated levels of mono-SUMO1 and increased high molecular weight conjugates in all brain regions. Immunoprecipitation of SUMOylated proteins from total brain extract and proteomic analysis revealed ~95 candidate proteins from a variety of functional classes, including a number of synaptic and cytoskeletal proteins. SUMO1 modification of synaptotagmin-1 was found to be elevated as compared to non-transgenic mice. This observation was associated with an age-dependent reduction in basal synaptic transmission and impaired presynaptic function as shown by altered paired pulse facilitation, as well as a decrease in spine density. The changes in neuronal function and morphology were also associated with a specific impairment in learning and memory while other behavioral features remained unchanged. These findings point to a significant contribution of SUMO1 modification on neuronal function which may have implications for mechanisms involved in mental retardation and neurodegeneration.
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36
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The glycosylation status of PrPC is a key factor in determining transmissible spongiform encephalopathy transmission between species. J Virol 2015; 89:4738-47. [PMID: 25673720 PMCID: PMC4403468 DOI: 10.1128/jvi.02296-14] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2014] [Accepted: 02/04/2015] [Indexed: 01/09/2023] Open
Abstract
UNLABELLED The risk of transmission of transmissible spongiform encephalopathies (TSE) between different species has been notoriously unpredictable because the mechanisms of transmission are not fully understood. A transmission barrier between species often prevents infection of a new host with a TSE agent. Nonetheless, some TSE agents are able to cross this barrier and infect new species, with devastating consequences. The host PrP(C) misfolds during disease pathogenesis and has a major role in controlling the transmission of agents between species, but sequence compatibility between host and agent PrP(C) does not fully explain host susceptibility. PrP(C) is posttranslationally modified by the addition of glycan moieties which have an important role in the infectious process. Here, we show in vivo that glycosylation of the host PrP(C) has a significant impact on the transmission of TSE between different host species. We infected mice carrying different glycosylated forms of PrP(C) with two human agents (sCJDMM2 and vCJD) and one hamster strain (263K). The absence of glycosylation at both or the first PrP(C) glycosylation site in the host results in almost complete resistance to disease. The absence of the second site of N-glycan has a dramatic effect on the barrier to transmission between host species, facilitating the transmission of sCJDMM2 to a host normally resistant to this agent. These results highlight glycosylation of PrP(C) as a key factor in determining the transmission efficiency of TSEs between different species. IMPORTANCE The risks of transmission of TSE between different species are difficult to predict due to a lack of knowledge over the mechanisms of disease transmission; some strains of TSE are able to cross a species barrier, while others do not. The host protein, PrP(C), plays a major role in disease transmission. PrP(C) undergoes posttranslational glycosylation, and the addition of these glycans may play a role in disease transmission. We infected mice that express different forms of glycosylated PrP(C) with three different TSE agents. We demonstrate that changing the glycosylation status of the host can have profound effects on disease transmission, changing host susceptibility and incubation times. Our results show that PrP(C) glycosylation is a key factor in determining risks of TSE transmission between species.
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37
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Zebrafish prion protein PrP2 controls collective migration process during lateral line sensory system development. PLoS One 2014; 9:e113331. [PMID: 25436888 PMCID: PMC4249873 DOI: 10.1371/journal.pone.0113331] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Accepted: 10/27/2014] [Indexed: 12/05/2022] Open
Abstract
Prion protein is involved in severe neurodegenerative disorders but its physiological role is still in debate due to an absence of major developmental defects in knockout mice. Previous reports in zebrafish indicate that the two prion genes, PrP1 and PrP2, are both involved in several steps of embryonic development thus providing a unique route to discover prion protein function. Here we investigate the role of PrP2 during development of a mechano-sensory system, the posterior lateral line, using morpholino knockdown and PrP2 targeted inactivation. We confirm the efficiency of the translation blocking morpholino at the protein level. Development of the posterior lateral line is altered in PrP2 morphants, including nerve axonal outgrowth and primordium migration defects. Reduced neuromast deposition was observed in PrP2 morphants as well as in PrP2−/− mutants. Rosette formation defects were observed in PrP2 morphants, strongly suggesting an abnormal primordium organization and reflecting loss of cell cohesion during migration of the primordium. In addition, the adherens junction proteins, E-cadherin and ß-catenin, were mis-localized after reduction of PrP2 expression and thus contribute to the primordium disorganization. Consequently, hair cell differentiation and number were affected and this resulted in reduced functional neuromasts. At later developmental stages, myelination of the posterior lateral line nerve was altered. Altogether, our study reports an essential role of PrP2 in collective migration process of the primordium and in neuromast formation, further implicating a role for prion protein in cell adhesion.
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Haïk S, Brandel JP. Infectious prion diseases in humans: cannibalism, iatrogenicity and zoonoses. INFECTION GENETICS AND EVOLUTION 2014; 26:303-12. [PMID: 24956437 DOI: 10.1016/j.meegid.2014.06.010] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2014] [Revised: 06/10/2014] [Accepted: 06/13/2014] [Indexed: 12/24/2022]
Abstract
In contrast with other neurodegenerative disorders associated to protein misfolding, human prion diseases include infectious forms (also called transmitted forms) such as kuru, iatrogenic Creutzfeldt-Jakob disease and variant Creutzfeldt-Jakob disease. The transmissible agent is thought to be solely composed of the abnormal isoform (PrP(Sc)) of the host-encoded prion protein that accumulated in the central nervous system of affected individuals. Compared to its normal counterpart, PrP(Sc) is β-sheet enriched and aggregated and its propagation is based on an autocatalytic conversion process. Increasing evidence supports the view that conformational variations of PrP(Sc) encoded the biological properties of the various prion strains that have been isolated by transmission studies in experimental models. Infectious forms of human prion diseases played a pivotal role in the emergence of the prion concept and in the characterization of the very unconventional properties of prions. They provide a unique model to understand how prion strains are selected and propagate in humans. Here, we review and discuss how genetic factors interplay with strain properties and route of transmission to influence disease susceptibility, incubation period and phenotypic expression in the light of the kuru epidemics due to ritual endocannibalism, the various series iatrogenic diseases secondary to extractive growth hormone treatment or dura mater graft and the epidemics of variant Creutzfeldt-Jakob disease linked to dietary exposure to the agent of bovine spongiform encephalopathy.
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Affiliation(s)
- Stéphane Haïk
- Sorbonne Universités, UPMC Univ Paris 06 UMR S 1127, Inserm, U 1127, CNRS UMR 7225, ICM, F-75013 Paris, France; AP-HP, Groupe hospitalier Pitié-Salpêtrière, Cellule Nationale de Référence des Maladies de Creutzfeldt-Jakob, F-75013 Paris, France; Centre National de Référence des Agents Transmissibles Non Conventionnels, F-75013 Paris, France.
| | - Jean-Philippe Brandel
- Sorbonne Universités, UPMC Univ Paris 06 UMR S 1127, Inserm, U 1127, CNRS UMR 7225, ICM, F-75013 Paris, France; AP-HP, Groupe hospitalier Pitié-Salpêtrière, Cellule Nationale de Référence des Maladies de Creutzfeldt-Jakob, F-75013 Paris, France; Centre National de Référence des Agents Transmissibles Non Conventionnels, F-75013 Paris, France
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Watts JC, Giles K, Patel S, Oehler A, DeArmond SJ, Prusiner SB. Evidence that bank vole PrP is a universal acceptor for prions. PLoS Pathog 2014; 10:e1003990. [PMID: 24699458 PMCID: PMC3974871 DOI: 10.1371/journal.ppat.1003990] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2013] [Accepted: 01/28/2014] [Indexed: 12/29/2022] Open
Abstract
Bank voles are uniquely susceptible to a wide range of prion strains isolated from many different species. To determine if this enhanced susceptibility to interspecies prion transmission is encoded within the sequence of the bank vole prion protein (BVPrP), we inoculated Tg(M109) and Tg(I109) mice, which express BVPrP containing either methionine or isoleucine at polymorphic codon 109, with 16 prion isolates from 8 different species: humans, cattle, elk, sheep, guinea pigs, hamsters, mice, and meadow voles. Efficient disease transmission was observed in both Tg(M109) and Tg(I109) mice. For instance, inoculation of the most common human prion strain, sporadic Creutzfeldt-Jakob disease (sCJD) subtype MM1, into Tg(M109) mice gave incubation periods of ∼200 days that were shortened slightly on second passage. Chronic wasting disease prions exhibited an incubation time of ∼250 days, which shortened to ∼150 days upon second passage in Tg(M109) mice. Unexpectedly, bovine spongiform encephalopathy and variant CJD prions caused rapid neurological dysfunction in Tg(M109) mice upon second passage, with incubation periods of 64 and 40 days, respectively. Despite the rapid incubation periods, other strain-specified properties of many prion isolates—including the size of proteinase K–resistant PrPSc, the pattern of cerebral PrPSc deposition, and the conformational stability—were remarkably conserved upon serial passage in Tg(M109) mice. Our results demonstrate that expression of BVPrP is sufficient to engender enhanced susceptibility to a diverse range of prion isolates, suggesting that BVPrP may be a universal acceptor for prions. Prions are infectious proteins that cause devastating neurodegenerative diseases in both humans and animals. Unlike other rodents, bank voles are highly susceptible to prions from many different species, suggesting that bank voles do not impose a “species barrier,” which normally restricts the transmission of prions from one species to another. We were curious as to whether the unprecedented promiscuity of bank voles for prions is due to the specific prion protein sequence expressed, or to some other factor inherent to bank vole physiology. To answer this question, we inoculated transgenic mice that express bank vole prion protein [Tg(BVPrP) mice] with a diverse set of prions deriving from eight different species. Like bank voles, Tg(BVPrP) mice were highly susceptible to prions from all species tested, demonstrating that the BVPrP sequence mediates the enhanced susceptibility of bank voles to prions. Because the amino acid sequences of mouse and BVPrP differ at only eight positions, our results demonstrate that alterations to a small subset of residues within PrP can have a profound effect on the susceptibility of an organism to prions from another species.
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Affiliation(s)
- Joel C Watts
- Institute for Neurodegenerative Diseases, University of California, San Francisco, San Francisco, California, United States of America; Department of Neurology, University of California, San Francisco, San Francisco, California, United States of America
| | - Kurt Giles
- Institute for Neurodegenerative Diseases, University of California, San Francisco, San Francisco, California, United States of America; Department of Neurology, University of California, San Francisco, San Francisco, California, United States of America
| | - Smita Patel
- Institute for Neurodegenerative Diseases, University of California, San Francisco, San Francisco, California, United States of America
| | - Abby Oehler
- Department of Pathology, University of California, San Francisco, San Francisco, California, United States of America
| | - Stephen J DeArmond
- Institute for Neurodegenerative Diseases, University of California, San Francisco, San Francisco, California, United States of America; Department of Pathology, University of California, San Francisco, San Francisco, California, United States of America
| | - Stanley B Prusiner
- Institute for Neurodegenerative Diseases, University of California, San Francisco, San Francisco, California, United States of America; Department of Neurology, University of California, San Francisco, San Francisco, California, United States of America
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Highly infectious prions generated by a single round of microplate-based protein misfolding cyclic amplification. mBio 2013; 5:e00829-13. [PMID: 24381300 PMCID: PMC3884057 DOI: 10.1128/mbio.00829-13] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Measurements of the presence of prions in biological tissues or fluids rely more and more on cell-free assays. Although protein misfolding cyclic amplification (PMCA) has emerged as a valuable, sensitive tool, it is currently hampered by its lack of robustness and rapidity for high-throughput purposes. Here, we made a number of improvements making it possible to amplify the maximum levels of scrapie prions in a single 48-h round and in a microplate format. The amplification rates and the infectious titer of the PMCA-formed prions appeared similar to those derived from the in vivo laboratory bioassays. This enhanced technique also amplified efficiently prions from different species, including those responsible for human variant Creutzfeldt-Jakob disease. This new format should help in developing ultrasensitive, high-throughput prion assays for cognitive, diagnostic, and therapeutic applications. IMPORTANCE The method developed here allows large-scale, fast, and reliable cell-free amplification of subinfectious levels of prions from different species. The sensitivity and rapidity achieved approach or equal those of other recently developed prion-seeded conversion assays. Our simplified assay may be amenable to high-throughput, automated purposes and serve in a complementary manner with other recently developed assays for urgently needed antemortem diagnostic tests, by using bodily fluids containing small amounts of prion infectivity. Such a combination of assays is of paramount importance to reduce the transfusion risk in the human population and to identify asymptomatic carriers of variant Creutzfeldt-Jakob disease.
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Cortes CJ, Qin K, Norstrom EM, Green WN, Bindokas VP, Mastrianni JA. Early Delivery of Misfolded PrP from ER to Lysosomes by Autophagy. Int J Cell Biol 2013; 2013:560421. [PMID: 24454378 PMCID: PMC3877647 DOI: 10.1155/2013/560421] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2013] [Accepted: 09/20/2013] [Indexed: 01/17/2023] Open
Abstract
Prion diseases are linked to the accumulation of a misfolded isoform (PrP(Sc)) of prion protein (PrP). Evidence suggests that lysosomes are degradation endpoints and sites of the accumulation of PrP(Sc). We questioned whether lysosomes participate in the early quality control of newly generated misfolded PrP. We found PrP carrying the disease-associated T182A mutation (Mut-PrP) was delivered to lysosomes in a Golgi-independent manner. Time-lapse live cell imaging revealed early formation and uptake of GFP-tagged Mut-PrP aggregates into LysoTracker labeled vesicles. Compared with Wt-PrP, Mut-PrP expression was associated with an elevation in several markers of the autophagy-lysosomal pathway, and it extensively colocalized with the autophagosome-specific marker, LC3B. In autophagy deficient (ATG5(-/-)) mouse embryonic fibroblasts, or in normal cells treated with the autophagy-inhibitor 3-MA, Mut-PrP colocalization with lysosomes was reduced to a similar extent. Additionally, 3-MA selectively impaired the degradation of insoluble Mut-PrP, resulting in an increase in protease-resistant PrP, whereas the induction of autophagy by rapamycin reduced it. These findings suggest that autophagy might function as a quality control mechanism to limit the accumulation of misfolded PrP that normally leads to the generation of PrP(Sc).
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Affiliation(s)
- Constanza J. Cortes
- Departments of Neurology, MC2030, The University of Chicago Pritzker School of Medicine, 5841 S. Maryland Avenue, Chicago, IL 60637, USA
| | - Kefeng Qin
- Departments of Neurology, MC2030, The University of Chicago Pritzker School of Medicine, 5841 S. Maryland Avenue, Chicago, IL 60637, USA
| | - Eric M. Norstrom
- Departments of Neurology, MC2030, The University of Chicago Pritzker School of Medicine, 5841 S. Maryland Avenue, Chicago, IL 60637, USA
| | - William N. Green
- Departments of Neurobiology, The University of Chicago Pritzker School of Medicine, Chicago, IL 60637, USA
| | - Vytautas P. Bindokas
- Departments of Neurobiology, The University of Chicago Pritzker School of Medicine, Chicago, IL 60637, USA
| | - James A. Mastrianni
- Departments of Neurology, MC2030, The University of Chicago Pritzker School of Medicine, 5841 S. Maryland Avenue, Chicago, IL 60637, USA
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Kretzschmar H, Tatzelt J. Prion disease: a tale of folds and strains. Brain Pathol 2013; 23:321-32. [PMID: 23587138 PMCID: PMC8029118 DOI: 10.1111/bpa.12045] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Accepted: 02/04/2013] [Indexed: 12/31/2022] Open
Abstract
Research on prions, the infectious agents of devastating neurological diseases in humans and animals, has been in the forefront of developing the concept of protein aggregation diseases. Prion diseases are distinguished from other neurodegenerative diseases by three peculiarities. First, prion diseases, in addition to being sporadic or genetic like all other neurodegenerative diseases, are infectious diseases. Animal models were developed early on (a long time before the advent of transgenic technology), and this has made possible the discovery of the prion protein as the infectious agent. Second, human prion diseases have true equivalents in animals, such as scrapie, which has been the subject of experimental research for many years. Variant Creutzfeldt-Jakob disease (vCJD) is a zoonosis caused by bovine spongiform encephalopathy (BSE) prions. Third, they show a wide variety of phenotypes in humans and animals, much wider than the variants of any other sporadic or genetic neurodegenerative disease. It has now become firmly established that particular PrP(Sc) isoforms are closely related to specific human prion strains. The variety of human prion diseases, still an enigma in its own right, is a focus of this article. Recently, a series of experiments has shown that the concept of aberrant protein folding and templating, first developed for prions, may apply to a variety of neurodegenerative diseases. In the wake of these discoveries, the term prion has come to be used for Aβ, α-synuclein, tau and possibly others. The self-propagation of alternative conformations seems to be the common denominator of these "prions," which in future, in order to avoid confusion, may have to be specified either as "neurodegenerative prions" or "infectious prions."
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Affiliation(s)
| | - Jörg Tatzelt
- NeurobiochemistryAdolf‐Butenandt‐InstituteLudwig‐Maximilians‐University MunichMunichGermany
- German Center for Neurodegenerative Diseases (DZNE)MunichGermany
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Cancellotti E, Mahal SP, Somerville R, Diack A, Brown D, Piccardo P, Weissmann C, Manson JC. Post-translational changes to PrP alter transmissible spongiform encephalopathy strain properties. EMBO J 2013; 32:756-69. [PMID: 23395905 PMCID: PMC3590993 DOI: 10.1038/emboj.2013.6] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2012] [Accepted: 01/02/2013] [Indexed: 01/09/2023] Open
Abstract
The agents responsible for transmissible spongiform encephalopathies (TSEs), or prion diseases, contain as a major component PrP(Sc), an abnormal conformer of the host glycoprotein PrP(C). TSE agents are distinguished by differences in phenotypic properties in the host, which nevertheless can contain PrP(Sc) with the same amino-acid sequence. If PrP alone carries information defining strain properties, these must be encoded by post-translational events. Here we investigated whether the glycosylation status of host PrP affects TSE strain characteristics. We inoculated wild-type mice with three TSE strains passaged through transgenic mice with PrP devoid of glycans at the first, second or both N-glycosylation sites. We compared the infectious properties of the emerging isolates with TSE strains passaged in wild-type mice by in vivo strain typing and by the standard scrapie cell assay in vitro. Strain-specific characteristics of the 79A TSE strain changed when PrP(Sc) was devoid of one or both glycans. Thus infectious properties of a TSE strain can be altered by post-translational changes to PrP which we propose result in the selection of mutant TSE strains.
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Affiliation(s)
- Enrico Cancellotti
- Division of Neurobiology, The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Midlothian, UK
| | - Sukhvir P Mahal
- Department of Infectology, Scripps Florida, Jupiter, FL, USA
| | - Robert Somerville
- Division of Neurobiology, The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Midlothian, UK
| | - Abigail Diack
- Division of Neurobiology, The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Midlothian, UK
| | - Deborah Brown
- Division of Neurobiology, The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Midlothian, UK
| | - Pedro Piccardo
- Division of Neurobiology, The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Midlothian, UK,Center for Biologics Evaluation and Research, Food and Drug Administration, Rockville, MD, USA
| | | | - Jean C Manson
- Division of Neurobiology, The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Midlothian, UK,Division of Neurobiology, The Roslin Institute & Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Midlothian EH25 9RG, UK. Tel.:+44 131 651900; Fax:+44 131 6519105; E-mail:
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Prion propagation and toxicity occur in vitro with two-phase kinetics specific to strain and neuronal type. J Virol 2012; 87:2535-48. [PMID: 23255799 DOI: 10.1128/jvi.03082-12] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Prion diseases, or transmissible spongiform encephalopathies (TSEs), are fatal neurodegenerative disorders that occur in humans and animals. The neuropathological hallmarks of TSEs are spongiosis, glial proliferation, and neuronal loss. The only known specific molecular marker of TSEs is the abnormal isoform (PrP(Sc)) of the host-encoded prion protein (PrP(C)), which accumulates in the brain of infected subjects and forms infectious prion particles. Although this transmissible agent lacks a specific nucleic acid component, several prion strains have been isolated. Prion strains are characterized by differences in disease outcome, PrP(Sc) distribution patterns, and brain lesion profiles at the terminal stage of the disease. The molecular factors and cellular mechanisms involved in strain-specific neuronal tropism and toxicity remain largely unknown. Currently, no cellular model exists to facilitate in vitro studies of these processes. A few cultured cell lines that maintain persistent scrapie infections have been developed, but only two of them have shown the cytotoxic effects associated with prion propagation. In this study, we have developed primary neuronal cultures to assess in vitro neuronal tropism and toxicity of different prion strains (scrapie strains 139A, ME7, and 22L). We have tested primary neuronal cultures enriched in cerebellar granular, striatal, or cortical neurons. Our results showed that (i) a strain-specific neuronal tropism operated in vitro; (ii) the cytotoxic effect varied among strains and neuronal cell types; (iii) prion propagation and toxicity occurred in two kinetic phases, a replicative phase followed by a toxic phase; and (iv) neurotoxicity peaked when abnormal PrP accumulation reached a plateau.
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Lee YH, Sohn HJ, Kim MJ, Kim HJ, Lee WY, Yun EI, Tark DS, Cho IS, Balachandran A. Strain characterization of the Korean CWD cases in 2001 and 2004. J Vet Med Sci 2012; 75:95-8. [PMID: 22972463 DOI: 10.1292/jvms.12-0077] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Chronic wasting disease (CWD) has been recognized as a naturally occurring prion disease in North American deer (Odocoileus species), Rocky Mountain elk (Cervus elaphus nelsoni) and moose (Alces alces). The disease was confirmed only in elk in the Republic of Korea in 2001, 2004 and 2005. Epidemiological investigations showed that CWD was introduced via importation of infected elk from Canada between 1994 and 1997. In spite of the increasing geographic distribution and host range of CWD, little is known about the prion strain (s) responsible for distinct outbreaks of the disease. We carried out strain characterization, using transgenic mice overexpressing elk prion protein, including clinical assessment, pathological examination and biochemical analyses, in brain tissues derived following primary through tertiary transmissions. The final incubation period was shortened to approximately 130 dpi due to adaptation. Biochemical profiles remained identical between passages. Lesion profiling in recipient mice brains showed similar patterns of vacuolation scores and intensity. It is clear that there were no biochemical or histopathological differences in Korean CWD cases in 2001 and 2004, suggesting a single strain was responsible for the outbreaks.
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Affiliation(s)
- Yoon-Hee Lee
- Animal, Plant and Fisheries Quarantine and Inspection Agency, Ministry for Food, Agriculture, Forestry and Fisheries, Anyang 430-757, Republic of Korea
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Sarasa R, Martínez A, Monleón E, Bolea R, Vargas A, Badiola JJ, Monzón M. Involvement of astrocytes in transmissible spongiform encephalopathies: a confocal microscopy study. Cell Tissue Res 2012; 350:127-34. [PMID: 22821398 DOI: 10.1007/s00441-012-1461-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2012] [Accepted: 05/31/2012] [Indexed: 02/02/2023]
Abstract
Astroglial proliferation associated with pathological prion protein (PrPsc) deposition is widely described in Transmissible Spongiform Encephalopathies (TSEs). However, little is known of the actual role played by glia in their pathogenesis. The aim of the study has been to determine whether PrPsc is located exclusively in neurons or in both neurons and glial cells present in the central nervous system in a natural Scrapie model. Samples of cerebellum from 25 Scrapie sheep from various flocks were sectioned. Following epitope retrieval with formic acid, proteinase K and heat treatment, primary antibody L42 and primary antibodies against glial fibrillary acidic protein were applied as prion- and astrocytic-specific markers, respectively. For visualization, a suitable mixture of fluorochrome-conjugated secondary antibodies was used. Relevant controls were processed in the same manner. As determined by confocal microscopy, PrPsc deposits co-localized with glial cells in all samples. Our results suggest that these cells can sustain active prion propagation, in agreement with similar findings from other studies of primary cell cultures and inoculated mice. Furthermore, despite ongoing debate regarding whether varied TSE sources show differences in their tropism for different cell lineages in the brains of affected animals, no differences in co-localization results were seen.
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Affiliation(s)
- Rocío Sarasa
- Research Centre for Encephalopathies and Transmissible Emerging Diseases, University of Zaragoza, C/ Miguel Servet 177, 50013 Zaragoza, Spain
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Mahal SP, Jablonski J, Suponitsky-Kroyter I, Oelschlegel AM, Herva ME, Oldstone M, Weissmann C. Propagation of RML prions in mice expressing PrP devoid of GPI anchor leads to formation of a novel, stable prion strain. PLoS Pathog 2012; 8:e1002746. [PMID: 22685404 PMCID: PMC3369955 DOI: 10.1371/journal.ppat.1002746] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2012] [Accepted: 04/27/2012] [Indexed: 12/03/2022] Open
Abstract
PrP(C), a host protein which in prion-infected animals is converted to PrP(Sc), is linked to the cell membrane by a GPI anchor. Mice expressing PrP(C) without GPI anchor (tgGPI⁻ mice), are susceptible to prion infection but accumulate anchorless PrP(Sc) extra-, rather than intracellularly. We investigated whether tgGPI⁻ mice could faithfully propagate prion strains despite the deviant structure and location of anchorless PrP(Sc). We found that RML and ME7, but not 22L prions propagated in tgGPI⁻ brain developed novel cell tropisms, as determined by the Cell Panel Assay (CPA). Surprisingly, the levels of proteinase K-resistant PrP(Sc) (PrP(res)) in RML- or ME7-infected tgGPI⁻ brain were 25-50 times higher than in wild-type brain. When returned to wild-type brain, ME7 prions recovered their original properties, however RML prions had given rise to a novel prion strain, designated SFL, which remained unchanged even after three passages in wild-type mice. Because both RML PrP(Sc) and SFL PrP(Sc) are stably propagated in wild-type mice we propose that the two conformations are separated by a high activation energy barrier which is abrogated in tgGPI⁻ mice.
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Affiliation(s)
- Sukhvir Paul Mahal
- Department of Infectology, Scripps Florida, Jupiter, Florida, United States of America
| | - Joseph Jablonski
- Department of Infectology, Scripps Florida, Jupiter, Florida, United States of America
| | | | | | - Maria Eugenia Herva
- Department of Infectology, Scripps Florida, Jupiter, Florida, United States of America
| | - Michael Oldstone
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, California, United States of America
| | - Charles Weissmann
- Department of Infectology, Scripps Florida, Jupiter, Florida, United States of America
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Herva ME, Weissman C. Cell-specific susceptibility to prion strains is a property of the intact cell. Prion 2012; 6:371-4. [PMID: 22561192 DOI: 10.4161/pri.20198] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Prions consist of PrP (Sc), a misfolded version of the cellular protein PrP (C). They occur in a variety of strains that share the amino acid sequence of PrP but differ in phenotypic properties, such as cell tropism and pathogenicity; strain-ness is attributed to the conformation of PrP (Sc). To gain insight as to how susceptibility of cells to a given prion strain comes about, we compared amplification of RML prions by PMCA, using cell lysates from related, RML-resistant and RML-susceptible cell lines as substrate. We found that both lysates supported amplification of RML PrP (Sc) equally well, despite a 280-fold difference in the susceptibility of the cells from which they were derived. Thus, susceptibility is an attribute of the intact cell.
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Affiliation(s)
- Maria E Herva
- Department of Infectology, Scripps Florida, Jupiter, FL, USA
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49
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Ayers JI, Schutt CR, Shikiya RA, Aguzzi A, Kincaid AE, Bartz JC. The strain-encoded relationship between PrP replication, stability and processing in neurons is predictive of the incubation period of disease. PLoS Pathog 2011; 7:e1001317. [PMID: 21437239 PMCID: PMC3060105 DOI: 10.1371/journal.ppat.1001317] [Citation(s) in RCA: 95] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2010] [Accepted: 02/10/2011] [Indexed: 02/07/2023] Open
Abstract
Prion strains are characterized by differences in the outcome of disease, most notably incubation period and neuropathological features. While it is established that the disease specific isoform of the prion protein, PrPSc, is an essential component of the infectious agent, the strain-specific relationship between PrPSc properties and the biological features of the resulting disease is not clear. To investigate this relationship, we examined the amplification efficiency and conformational stability of PrPSc from eight hamster-adapted prion strains and compared it to the resulting incubation period of disease and processing of PrPSc in neurons and glia. We found that short incubation period strains were characterized by more efficient PrPSc amplification and higher PrPSc conformational stabilities compared to long incubation period strains. In the CNS, the short incubation period strains were characterized by the accumulation of N-terminally truncated PrPSc in the soma of neurons, astrocytes and microglia in contrast to long incubation period strains where PrPSc did not accumulate to detectable levels in the soma of neurons but was detected in glia similar to short incubation period strains. These results are inconsistent with the hypothesis that a decrease in conformational stability results in a corresponding increase in replication efficiency and suggest that glia mediated neurodegeneration results in longer survival times compared to direct replication of PrPSc in neurons. Prion diseases are a group of infectious fatal neurodegenerative diseases that affect animals including humans. This unique infectious agent is the result of a post-translational conformational change of the normal form of the prion protein, PrPC, to an infectious form of the prion protein, PrPSc. Different strains of the infectious agent result in characteristic incubation periods and neuropathological features within a single host species. These strain-specific differences in disease outcome are likely due to strain-specific conformations of PrPSc, though the mechanisms by which different conformation can affect prion strain properties are not understood. The aim of this study was to investigate the relationship between the biochemical properties of PrPSc to the corresponding neuropathological characteristics of eight hamster-adapted prion strains. Our findings indicate that PrPSc from short incubation period strains were more efficiently replicated, had a more stable conformation, and were observed to be more resistant to clearance from the soma of neurons compared to prion strains with a relatively long incubation period. These results suggest the progression of prion disease is influenced by the balance between replication and clearance of PrPSc in neurons.
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Affiliation(s)
- Jacob I. Ayers
- Department of Medical Microbiology and Immunology, Creighton University, Omaha, Nebraska, United States of America
| | - Charles R. Schutt
- Department of Medical Microbiology and Immunology, Creighton University, Omaha, Nebraska, United States of America
| | - Ronald A. Shikiya
- Department of Medical Microbiology and Immunology, Creighton University, Omaha, Nebraska, United States of America
| | - Adriano Aguzzi
- Institute of Neuropathology, University Hospital Zurich, Zurich, Switzerland
| | - Anthony E. Kincaid
- Department of Physical Therapy, Creighton University, Omaha, Nebraska, United States of America
| | - Jason C. Bartz
- Department of Medical Microbiology and Immunology, Creighton University, Omaha, Nebraska, United States of America
- * E-mail:
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Abstract
Infection by prions involves conversion of a host-encoded cell surface protein (PrP(C)) to a disease-related isoform (PrP(Sc)). PrP(C) carries two glycosylation sites variably occupied by complex N-glycans, which have been suggested by previous studies to influence the susceptibility to these diseases and to determine characteristics of prion strains. We used the Rov cell system, which is susceptible to sheep prions, to generate a series of PrP(C) glycosylation mutants with mutations at one or both attachment sites. We examined their subcellular trafficking and ability to convert into PrP(Sc) and to sustain stable prion propagation in the absence of wild-type PrP. The susceptibility to infection of mutants monoglycosylated at either site differed dramatically depending on the amino acid substitution. Aglycosylated double mutants showed overaccumulation in the Golgi compartment and failed to be infected. Introduction of an ectopic glycosylation site near the N terminus fully restored cell surface expression of PrP but not convertibility into PrP(Sc), while PrP(C) with three glycosylation sites conferred cell permissiveness to infection similarly to the wild type. In contrast, predominantly aglycosylated molecules with nonmutated N-glycosylation sequons, produced in cells expressing glycosylphosphatidylinositol-anchorless PrP(C), were able to form infectious PrP(Sc). Together our findings suggest that glycosylation is important for efficient trafficking of anchored PrP to the cell surface and sustained prion propagation. However, properly trafficked glycosylation mutants were not necessarily prone to conversion, thus making it difficult in such studies to discern whether the amino acid changes or glycan chain removal most influences the permissiveness to prion infection.
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