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Forloni G, Chiesa R, Bugiani O, Salmona M, Tagliavini F. Review: PrP 106-126 - 25 years after. Neuropathol Appl Neurobiol 2019; 45:430-440. [PMID: 30635947 DOI: 10.1111/nan.12538] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Accepted: 12/10/2018] [Indexed: 12/14/2022]
Abstract
A quarter of a century ago, we proposed an innovative approach to study the pathogenesis of prion disease, one of the most intriguing biomedical problems that remains unresolved. The synthesis of a peptide homologous to residues 106-126 of the human prion protein (PrP106-126), a sequence present in the PrP amyloid protein of Gerstmann-Sträussler-Scheinker syndrome patients, provided a tractable tool for investigating the mechanisms of neurotoxicity. Together with several other discoveries at the beginning of the 1990s, PrP106-126 contributed to underpin the role of amyloid in the pathogenesis of protein-misfolding neurodegenerative disorders. Later, the role of oligomers on one hand and of prion-like spreading of pathology on the other further clarified mechanisms shared by different neurodegenerative conditions. Our original report on PrP106-126 neurotoxicity also highlighted a role for programmed cell death in CNS diseases. In this review, we analyse the prion research context in which PrP106-126 first appeared and the advances in our understanding of prion disease pathogenesis and therapeutic perspectives 25 years later.
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Affiliation(s)
- G Forloni
- Department of Neuroscience, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Milano, Italy
| | - R Chiesa
- Department of Neuroscience, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Milano, Italy
| | - O Bugiani
- Department of Biochemistry, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Milano, Italy
| | - M Salmona
- Department of Biochemistry, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Milano, Italy
| | - F Tagliavini
- Fondazione IRCCS Istituto Neurologico "Carlo Besta", Milano, Italy
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2
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Ning L, Mu Y. Aggregation of PrP106-126 on surfaces of neutral and negatively charged membranes studied by molecular dynamics simulations. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2018; 1860:1936-1948. [PMID: 29550288 DOI: 10.1016/j.bbamem.2018.03.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2017] [Revised: 03/08/2018] [Accepted: 03/08/2018] [Indexed: 01/28/2023]
Abstract
Prion diseases are neurodegenerative disorders characterized by the aggregation of an abnormal form of prion protein. The interaction of prion protein and cellular membrane is crucial to elucidate the occurrence and development of prion diseases. Its fragment, residues 106-126, has been proven to maintain the pathological properties of misfolded prion and was used as a model peptide. In this study, explicit solvent molecular dynamics (MD) simulations were carried out to investigate the adsorption, folding and aggregation of PrP106-126 with different sizes (2-peptides, 4-peptides and 6-peptides) on the surface of both pure neutral POPC (1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine) and negatively charged POPC/POPG (1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoglycerol) (3:1) lipids. MD simulation results show that PrP106-126 display strong affinity with POPC/POPG but does not interact with pure POPC. The positively charged and polar residues participating hydrogen bonding with membrane promote the adsorption of PrP106-126. The presence of POPC and POPC/POPG exert limited influence on the secondary structures of PrP106-126 and random coil structures are predominant in all simulation systems. Upon the adsorption on the POPC/POPG surface, the aggregation states of PrP106-126 have been changed and more small oligomers were observed. This work provides insights into the interactions of PrP106-126 and membranes with different compositions in atomic level, which expand our understanding the role membrane plays in the development of prion diseases. This article is part of a Special Issue entitled: Protein Aggregation and Misfolding at the Cell Membrane Interface edited by Ayyalusamy Ramamoorthy.
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Affiliation(s)
- Lulu Ning
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Singapore
| | - Yuguang Mu
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Singapore.
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3
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Pan J, Sahoo PK, Dalzini A, Hayati Z, Aryal CM, Teng P, Cai J, Gutierrez HR, Song L. Membrane Disruption Mechanism of a Prion Peptide (106-126) Investigated by Atomic Force Microscopy, Raman and Electron Paramagnetic Resonance Spectroscopy. J Phys Chem B 2017; 121:5058-5071. [PMID: 28459565 PMCID: PMC5770145 DOI: 10.1021/acs.jpcb.7b02772] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
A fragment of the human prion protein spanning residues 106-126 (PrP106-126) recapitulates many essential properties of the disease-causing protein such as amyloidogenicity and cytotoxicity. PrP106-126 has an amphipathic characteristic that resembles many antimicrobial peptides (AMPs). Therefore, the toxic effect of PrP106-126 could arise from a direct association of monomeric peptides with the membrane matrix. Several experimental approaches are employed to scrutinize the impacts of monomeric PrP106-126 on model lipid membranes. Porous defects in planar bilayers are observed by using solution atomic force microscopy. Adding cholesterol does not impede defect formation. A force spectroscopy experiment shows that PrP106-126 reduces Young's modulus of planar lipid bilayers. We use Raman microspectroscopy to study the effect of PrP106-126 on lipid atomic vibrational dynamics. For phosphatidylcholine lipids, PrP106-126 disorders the intrachain conformation, while the interchain interaction is not altered; for phosphatidylethanolamine lipids, PrP106-126 increases the interchain interaction, while the intrachain conformational order remains similar. We explain the observed differences by considering different modes of peptide insertion. Finally, electron paramagnetic resonance spectroscopy shows that PrP106-126 progressively decreases the orientational order of lipid acyl chains in magnetically aligned bicelles. Together, our experimental data support the proposition that monomeric PrP106-126 can disrupt lipid membranes by using similar mechanisms found in AMPs.
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Affiliation(s)
- Jianjun Pan
- Department of Physics, University of South Florida, Tampa, Florida 33620, United States
| | - Prasana K. Sahoo
- Department of Physics, University of South Florida, Tampa, Florida 33620, United States
| | - Annalisa Dalzini
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310, United States
| | - Zahra Hayati
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310, United States
| | - Chinta M. Aryal
- Department of Physics, University of South Florida, Tampa, Florida 33620, United States
| | - Peng Teng
- Department of Chemistry, University of South Florida, Tampa, Florida 33620, United States
| | - Jianfeng Cai
- Department of Chemistry, University of South Florida, Tampa, Florida 33620, United States
| | | | - Likai Song
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310, United States
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4
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Vilches S, Vergara C, Nicolás O, Sanclimens G, Merino S, Varón S, Acosta GA, Albericio F, Royo M, Río JAD, Gavín R. Neurotoxicity of prion peptides mimicking the central domain of the cellular prion protein. PLoS One 2013; 8:e70881. [PMID: 23940658 PMCID: PMC3733940 DOI: 10.1371/journal.pone.0070881] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2013] [Accepted: 06/25/2013] [Indexed: 12/20/2022] Open
Abstract
The physiological functions of PrP(C) remain enigmatic, but the central domain, comprising highly conserved regions of the protein may play an important role. Indeed, a large number of studies indicate that synthetic peptides containing residues 106-126 (CR) located in the central domain (CD, 95-133) of PrP(C) are neurotoxic. The central domain comprises two chemically distinct subdomains, the charge cluster (CC, 95-110) and a hydrophobic region (HR, 112-133). The aim of the present study was to establish the individual cytotoxicity of CC, HR and CD. Our results show that only the CD peptide is neurotoxic. Biochemical, Transmission Electron Microscopy and Atomic Force Microscopy experiments demonstrated that the CD peptide is able to activate caspase-3 and disrupt the cell membrane, leading to cell death.
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Affiliation(s)
- Silvia Vilches
- Molecular and Cellular Neurobiotechnology, Institute for Bioengineering of Catalonia (IBEC), Barcelona, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), Barcelona, Spain
| | - Cristina Vergara
- Molecular and Cellular Neurobiotechnology, Institute for Bioengineering of Catalonia (IBEC), Barcelona, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), Barcelona, Spain
| | - Oriol Nicolás
- Molecular and Cellular Neurobiotechnology, Institute for Bioengineering of Catalonia (IBEC), Barcelona, Spain
- Department of Cell Biology, Faculty of Biology, University of Barcelona, Barcelona, Spain
| | - Gloria Sanclimens
- Combinatorial Chemistry Unit, Scientific Park of Barcelona, Barcelona, Spain
| | - Sandra Merino
- Department of Physicochemistry, Faculty of Pharmacy, University of Barcelona, Barcelona, Spain
| | - Sonia Varón
- Combinatorial Chemistry Unit, Scientific Park of Barcelona, Barcelona, Spain
| | - Gerardo A. Acosta
- Institute for Research in Biomedicine (IRB), Barcelona, Spain
- Networking Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Barcelona, Spain
| | - Fernando Albericio
- Institute for Research in Biomedicine (IRB), Barcelona, Spain
- Networking Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Barcelona, Spain
- Department of Organic Chemistry, Faculty of Chemistry, University of Barcelona, Barcelona, Spain
| | - Miriam Royo
- Combinatorial Chemistry Unit, Scientific Park of Barcelona, Barcelona, Spain
- Networking Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Barcelona, Spain
| | - José A. Del Río
- Molecular and Cellular Neurobiotechnology, Institute for Bioengineering of Catalonia (IBEC), Barcelona, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), Barcelona, Spain
- Department of Cell Biology, Faculty of Biology, University of Barcelona, Barcelona, Spain
| | - Rosalina Gavín
- Molecular and Cellular Neurobiotechnology, Institute for Bioengineering of Catalonia (IBEC), Barcelona, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), Barcelona, Spain
- Department of Cell Biology, Faculty of Biology, University of Barcelona, Barcelona, Spain
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Cronier S, Carimalo J, Schaeffer B, Jaumain E, Béringue V, Miquel MC, Laude H, Peyrin JM. Endogenous prion protein conversion is required for prion-induced neuritic alterations and neuronal death. FASEB J 2012; 26:3854-61. [PMID: 22661006 DOI: 10.1096/fj.11-201772] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Prions cause fatal neurodegenerative conditions and result from the conversion of host-encoded cellular prion protein (PrP(C)) into abnormally folded scrapie PrP (PrP(Sc)). Prions can propagate both in neurons and astrocytes, yet neurotoxicity mechanisms remain unclear. Recently, PrP(C) was proposed to mediate neurotoxic signaling of β-sheet-rich PrP and non-PrP conformers independently of conversion. To investigate the role of astrocytes and neuronal PrP(C) in prion-induced neurodegeneration, we set up neuron and astrocyte primary cocultures derived from PrP transgenic mice. In this system, prion-infected astrocytes delivered ovine PrP(Sc) to neurons lacking PrP(C) (prion-resistant), or expressing a PrP(C) convertible (sheep) or not (mouse, human). We show that interaction between neuronal PrP(C) and exogenous PrP(Sc) was not sufficient to induce neuronal death but that efficient PrP(C) conversion was required for prion-associated neurotoxicity. Prion-infected astrocytes markedly accelerated neurodegeneration in homologous cocultures compared to infected single neuronal cultures, despite no detectable neurotoxin release. Finally, PrP(Sc) accumulation in neurons led to neuritic damages and cell death, both potentiated by glutamate and reactive oxygen species. Thus, conversion of neuronal PrP(C) rather than PrP(C)-mediated neurotoxic signaling appears as the main culprit in prion-induced neurodegeneration. We suggest that active prion replication in neurons sensitizes them to environmental stress regulated by neighboring cells, including astrocytes.
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Affiliation(s)
- Sabrina Cronier
- UR892, Virologie et Immunologie Moléculaires, Institut National de Recherche Agronomique, Jouy-en-Josas, France.
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6
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New insights into cellular prion protein (PrPc) functions: the "ying and yang" of a relevant protein. ACTA ACUST UNITED AC 2009; 61:170-84. [PMID: 19523487 DOI: 10.1016/j.brainresrev.2009.06.002] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2008] [Revised: 05/26/2009] [Accepted: 06/03/2009] [Indexed: 12/19/2022]
Abstract
The conversion of cellular prion protein (PrP(c)), a GPI-anchored protein, into a protease-K-resistant and infective form (generally termed PrP(sc)) is mainly responsible for Transmissible Spongiform Encephalopathies (TSEs), characterized by neuronal degeneration and progressive loss of basic brain functions. Although PrP(c) is expressed by a wide range of tissues throughout the body, the complete repertoire of its functions has not been fully determined. Recent studies have confirmed its participation in basic physiological processes such as cell proliferation and the regulation of cellular homeostasis. Other studies indicate that PrP(c) interacts with several molecules to activate signaling cascades with a high number of cellular effects. To determine PrP(c) functions, transgenic mouse models have been generated in the last decade. In particular, mice lacking specific domains of the PrP(c) protein have revealed the contribution of these domains to neurodegenerative processes. A dual role of PrP(c) has been shown, since most authors report protective roles for this protein while others describe pro-apoptotic functions. In this review, we summarize new findings on PrP(c) functions, especially those related to neural degeneration and cell signaling.
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Henriques ST, Pattenden LK, Aguilar MI, Castanho MARB. The Toxicity of Prion Protein Fragment PrP(106−126) is Not Mediated by Membrane Permeabilization as Shown by a M112W Substitution. Biochemistry 2009; 48:4198-208. [DOI: 10.1021/bi900009d] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Sónia Troeira Henriques
- Instituto de Medicina Molecular, Faculdade de Medicina da Universidade de Lisboa, Av. Egas Moniz, Edifício Egas Moniz, 1649-028 Lisboa, Portugal
| | - Leonard Keith Pattenden
- Department of Biochemistry & Molecular Biology, Monash University, Victoria, 3800 Clayton, Australia
| | - Marie-Isabel Aguilar
- Department of Biochemistry & Molecular Biology, Monash University, Victoria, 3800 Clayton, Australia
| | - Miguel A. R. B. Castanho
- Instituto de Medicina Molecular, Faculdade de Medicina da Universidade de Lisboa, Av. Egas Moniz, Edifício Egas Moniz, 1649-028 Lisboa, Portugal
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8
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Abstract
Transmissible spongiform encephalopathies are neurodegenerative diseases characterized by the accumulation of an abnormal isoform of the prion protein PrP(Sc). Its fragment 106-126 has been reported to maintain most of the pathological features of PrP(Sc), and a role in neurodegeneration has been proposed based on the modulation of membrane properties and channel formation. The ability of PrP(Sc) to modulate membranes and/or form channels in membranes has not been clearly demonstrated; however, if these processes are important, peptide-membrane interactions would be a key feature in the toxicity of PrP(Sc). In this work, the interaction of PrP(106-126) with model membranes comprising typical lipid identities, as well as more specialized lipids such as phosphatidylserine and GM1 ganglioside, was examined using surface plasmon resonance and fluorescence methodologies. This comprehensive study examines different parameters relevant to characterization of peptide-membrane interactions, including membrane charge, viscosity, lipid composition, pH, and ionic strength. We report that PrP(106-126) has a low affinity for lipid membranes under physiological conditions without evidence of membrane disturbances. Membrane insertion and leakage occur only under conditions in which strong electrostatic interactions operate. These results support the hypothesis that the physiological prion protein PrP(C) mediates PrP(106-126) toxic effects in neuronal cells.
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9
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Hu W, Kieseier B, Frohman E, Eagar TN, Rosenberg RN, Hartung HP, Stüve O. Prion proteins: Physiological functions and role in neurological disorders. J Neurol Sci 2008; 264:1-8. [PMID: 17707411 DOI: 10.1016/j.jns.2007.06.019] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2007] [Revised: 05/01/2007] [Accepted: 06/08/2007] [Indexed: 02/01/2023]
Abstract
Stanley Prusiner was the first to promote the concept of misfolded proteins as a cause for neurological disease. It has since been shown by him and other investigators that the scrapie isoform of prion protein (PrP(Sc)) functions as an infectious agent in numerous human and non-human disorders of the central nervous system (CNS). Interestingly, other organ systems appear to be less affected, and do not appear to lead to major co-morbidities. The physiological function of the endogenous cellular form of the prion protein (PrP(C)) is much less clear. It is intriguing that PrP(c) is expressed on most tissues in mammals, suggesting not only biological functions outside the CNS, but also a role other than the propagation of its misfolded isotype. In this review, we summarize accumulating in vitro and in vivo evidence regarding the physiological functions of PrP(C) in the nervous system, as well as in lymphoid organs.
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Affiliation(s)
- Wei Hu
- Department of Neurology, University of Texas Southwestern Medical Center at Dallas, TX 75390-9036, United States
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10
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Zhong J, Zheng W, Huang L, Hong Y, Wang L, Qiu Y, Sha Y. PrP106–126 amide causes the semi-penetrated poration in the supported lipid bilayers. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2007; 1768:1420-9. [PMID: 17451641 DOI: 10.1016/j.bbamem.2007.03.003] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2006] [Revised: 02/27/2007] [Accepted: 03/02/2007] [Indexed: 11/17/2022]
Abstract
A major hallmark of prion diseases is the cerebral amyloid accumulation of the pathogenic PrP(Sc), an abnormally misfolded, protease-resistant, and beta-sheet rich protein. PrP106-126 is the key domain responsible for the conformational conversion and aggregation of PrP. It shares important physicochemical characteristics with PrP(Sc) and presents similar neurotoxicity as PrP(Sc). By combination of fluorescence polarization, dye release assay and in situ time-lapse atomic force microscopy (AFM), we investigated the PrP106-126 amide interacting with the large unilamellar vesicles (LUVs) and the supported lipid bilayers (SLBs). The results suggest that the interactions involve a poration-mediated process: firstly, the peptide binding results in the formation of pores in the membranes, which penetrate only half of the membranes; subsequently, PrP106-126 amide undergoes the poration-mediated diffusion in the SLBs, represented by the formation and expansion of the flat high-rise domains (FHDs). The possible mechanisms of the interactions between PrP106-126 amide and lipid membranes are proposed based on our observations.
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Affiliation(s)
- Jian Zhong
- Single-molecule and Nanobiology Laboratory, Department of Biophysics, School of Basic Medical Sciences and Biomed-X Center, Peking University, Beijing 100083, China
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11
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Abstract
Prions, the infectious agents of transmissible spongiform encephalopathies (TSEs), have defied full characterization for decades. The dogma has been that prions lack nucleic acids and are composed of a pathological, self-inducing form of the host's prion protein (PrP). Recent progress in propagating TSE infectivity in cell-free systems has effectively ruled out the involvement of foreign nucleic acids. However, host-derived nucleic acids or other non-PrP molecules seem to be crucial. Interactions between TSE-associated PrP and its normal counterpart are also pathologically important, so the physiological functions of normal PrP and how they might be corrupted by TSE infections have been the subject of recent research.
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Affiliation(s)
- Byron Caughey
- National Institute of Allergy and Infectious Disease, National Institutes of Health, Rocky Mountain Laboratories, 903 South 4th Street, Hamilton, Montana 59840, USA.
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12
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Abstract
Neuronal vacuolation (spongiosis), neuronal death, and pronounced glial reactions are the hallmarks of transmissible spongiform encephalopathies (TSEs), or prion diseases. A wealth of physical, biochemical, and immunological evidence indicates that the TSE agent, termed prion, does not contain agent-specific nucleic acid encoding its own constituents, as is the case for all other infectious pathogens. Also, no adaptive immune responses are elicited upon infection. A defining feature of TSEs is the deposition, mainly in the brain and lymphoreticular tissues, of an aggregated and structurally abnormal protein, designated PrP(Sc) or PrP-res, which represents a conformational isomer of the ubiquitous surface protein PrP(C). Biochemical and genetic evidence link PrP and its gene to the disease. Although TSEs are by definition transmissible, a growing number of Prnp-associated non-infectious neurodegenerative proteinopathies are now being recognized.
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Affiliation(s)
- Adriano Aguzzi
- Institute of Neuropathology, Universitätsspital Zürich, Zürich, Switzerland.
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13
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Gavín R, Braun N, Nicolas O, Parra B, Ureña JM, Mingorance A, Soriano E, Torres JM, Aguzzi A, del Río JA. PrP(106-126) activates neuronal intracellular kinases and Egr1 synthesis through activation of NADPH-oxidase independently of PrPc. FEBS Lett 2005; 579:4099-106. [PMID: 16023105 DOI: 10.1016/j.febslet.2005.06.037] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2005] [Revised: 06/20/2005] [Accepted: 06/22/2005] [Indexed: 11/28/2022]
Abstract
Prion diseases are characterised by severe neural lesions linked to the presence of an abnormal protease-resistant isoform of cellular prion protein (PrPc). The peptide PrP(106-126) is widely used as a model of neurotoxicity in prion diseases. Here, we examine in detail the intracellular signalling cascades induced by PrP(106-126) in cortical neurons and the participation of PrPc. We show that PrP(106-126) induces the activation of subsets of intracellular kinases (e.g., ERK1/2), early growth response 1 synthesis and induces caspase-3 activity, all of which are mediated by nicotinamide adenine dinucleotide phosphate hydrogen-oxidase activity and oxidative stress. However, cells lacking PrPc are similarly affected after peptide exposure, and this questions the involvement of PrPc in these effects.
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Affiliation(s)
- Rosalina Gavín
- Development and Regeneration of the CNS, Department of Cell Biology, Barcelona Science Park - IRB, University of Barcelona, Spain
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14
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Bergström AL, Cordes H, Zsurger N, Heegaard PMH, Laursen H, Chabry J. Amidation and structure relaxation abolish the neurotoxicity of the prion peptide PrP106-126 in vivo and in vitro. J Biol Chem 2005; 280:23114-21. [PMID: 15824101 DOI: 10.1074/jbc.m500210200] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
One of the major pathological hallmarks of transmissible spongiform encephalopathies (TSEs) is the accumulation of a pathogenic (scrapie) isoform (PrP(Sc)) of the cellular prion protein (PrP(C)) primarily in the central nervous system. The synthetic prion peptide PrP106-126 shares many characteristics with PrP(Sc) in that it shows PrP(C)-dependent neurotoxicity both in vivo and in vitro. Moreover, PrP106-126 in vitro neurotoxicity has been closely associated with the ability to form fibrils. Here, we studied the in vivo neurotoxicity of molecular variants of PrP106-126 toward retinal neurons using electroretinographic recordings in mice after intraocular injections of the peptides. We found that amidation and structure relaxation of PrP106-126 significantly reduced the neurotoxicity in vivo. This was also found in vitro in primary neuronal cultures from mouse and rat brain. Thioflavin T binding studies showed that amidation and structure relaxation significantly reduced the ability of PrP106-126 to attain fibrillar structures in physiological salt solutions. This study hence supports the assumption that the neurotoxic potential of PrP106-126 is closely related to its ability to attain secondary structure.
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Affiliation(s)
- Ann-Louise Bergström
- Danish Institute for Food and Veterinary Research, Department of Veterinary Diagnostics and Research, Copenhagen.
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15
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16
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Heegaard PMH, Pedersen HG, Flink J, Boas U. Amyloid aggregates of the prion peptide PrP106-126 are destabilised by oxidation and by the action of dendrimers. FEBS Lett 2005; 577:127-33. [PMID: 15527773 DOI: 10.1016/j.febslet.2004.09.073] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2004] [Accepted: 09/24/2004] [Indexed: 10/26/2022]
Abstract
The prion protein (PrP) peptide 106-126 forms amyloid aggregates in vitro and this sequence is speculated to be involved in the formation of amyloid fibrils by the abnormally folded PrP protein (PrPSc) found in spongiform encephalopathies. It is shown here by incubation experiments in water using Thioflavin T (ThT) as a fluorescent probe for amyloid formation that changes in C-terminal charge, oxidation state and conformational stabilisation lead to large changes in amyloid forming behaviour (amyloidogenicity) of this peptide. Amyloid formation is favoured by a charged C-terminus and is strongly inhibited by oxidation. Furthermore, cationic dendrimers are shown to perturb peptide fibrillation in a process dependent on the nature of the charged groups on the dendrimer surface.
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Affiliation(s)
- Peter M H Heegaard
- Department of Veterinary Diagnostics and Research, Danish Institute for Food and Veterinary Research, 27, Bülowsvej, DK 1790 Copenhagen V, Denmark.
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18
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Abstract
Devising approaches to the therapy of transmissible spongiform encephalopathies, or prion diseases, is beset by many difficulties. For one, the nature of the infectious agent, the prion, is understood only in outline, and its composition, structure, and mode of replication are still shrouded in mystery. In addition, the mechanism of pathogenesis is not well understood. Because clinical disease affects mainly the brain parenchyme, therapeutic agents must be able to traverse the brain-blood barrier (BBB) or have to be introduced directly into the cerebrospinal fluid or brain tissue. And finally, because the disease is usually recognized only after onset of severe clinical symptoms, the question arises as to whether the neurodegenerative processes can be reversed to any extent after a successful eradication of the agent.
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Affiliation(s)
- Charles Weissmann
- Department of Neurodegenerative Disease/MRC Prion Unit, Institute of Neurology, Queen Square, London WC1N 3BG, UK.
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19
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Affiliation(s)
- Adriano Aguzzi
- Department of Pathology, University Hospital of Zürich, Schmelzbergstr. 12, CH-8091 Zürich, Switzerland.
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20
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Abstract
This review examines recent attempts to advance the understanding of the mechanism by which neurones die in prion disease. Prion diseases or transmissible spongiform encephalopathies are characterized by the conversion of a normal glycoprotein, the prion protein, to a protease-resistant form that is suggested to be both the infectious agent and the cause of the rapid neurodegeneration in the disease. Death of the patient results from this widespread neuronal loss. Thus understanding the mechanism by which the abnormal form of the prion protein causes neuronal death might lead to treatments that would prevent the life-threatening nature of these diseases.
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Affiliation(s)
- David R Brown
- Department of Biology and Biochemistry, University of Bath, Bath, UK.
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Tagliavini F, Forloni G, D'Ursi P, Bugiani O, Salmona M. Studies on peptide fragments of prion proteins. ADVANCES IN PROTEIN CHEMISTRY 2002; 57:171-201. [PMID: 11447690 DOI: 10.1016/s0065-3233(01)57022-9] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- F Tagliavini
- Istituto Nazionale Neurologico Carlo Besta, Milano, Italy
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22
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Asante EA, Collinge J. Transgenic studies of the influence of the PrP structure on TSE diseases. ADVANCES IN PROTEIN CHEMISTRY 2002; 57:273-311. [PMID: 11447693 DOI: 10.1016/s0065-3233(01)57025-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- E A Asante
- MRC Prion Unit and Department of Neurogenetics, Imperial College School of Medicine at St. Mary's, London W2 1PG, United Kingdom
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23
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Gauczynski S, Hundt C, Leucht C, Weiss S. Interaction of prion proteins with cell surface receptors, molecular chaperones, and other molecules. ADVANCES IN PROTEIN CHEMISTRY 2002; 57:229-72. [PMID: 11447692 DOI: 10.1016/s0065-3233(01)57024-2] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- S Gauczynski
- Laboratorium für Molekulare, Biologie-Genzentrum-Institut für Biochemie der LMU München, D-81377 Munich, Germany
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24
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Kourie JI. Mechanisms of prion-induced modifications in membrane transport properties: implications for signal transduction and neurotoxicity. Chem Biol Interact 2001; 138:1-26. [PMID: 11640912 DOI: 10.1016/s0009-2797(01)00228-9] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Prion-related encephalopathies are associated with the conversion of a normal cellular isoform of prion protein (PrP(c)) to an abnormal pathologic scrapie isoform (PrP(Sc)). The conversion of this single polypeptide chain involves a reduction in the alpha-helices and an increase in beta-sheet content. This change in the content ratio of alpha-helices to beta-sheets may explain the diversity in the proposed mechanisms of action. Many of the pathogenic properties of PrP(Sc), such as neurotoxicity, proteinase-resistant properties and induction of hypertrophy and proliferation of astrocytes, have been attributed to the peptide fragment corresponding to residues 106-126 of prion (PrP[106-126]). In particular, the amyloidogenic and hydrophobic core AGAAAAGA has been implicated in modulation of neurotoxicity and the secondary structure of PrP[106-126]. Because of some similarities between the properties of PrP[106-126] and PrP(Sc), the former is used as a useful tool to characterize the pharmacological and biophysical properties of PrP(Sc) in general and of that domain in particular, by various laboratories. However, it is important to note that by no means can PrP[106-126] be considered a complete equivalent to PrP(Sc) in function. Several hypotheses have been proposed to explain prion-induced neurodegenerative diseases. These non-exclusive hypotheses include: (i) changes in the membrane microviscosity; (ii) changes in the intracellular Ca(2+) homeostasis; (iii) superoxide dismutase and Cu(2+) homeostasis; and (iv) changes in the immune system. The prion-induced modification in Ca(2+) homeostasis is the result of: (1) prion interaction with intrinsic ion transport proteins, e.g. L-type Ca(2+) channels in the surface membrane, and IP(3)-modulated Ca(2+) channels in the internal membranes, and/or (2) formation of cation channels. These two mechanisms of action lead to changes in Ca(2+) homeostasis that further augment the abnormal electrical activity and the distortion of signal transduction causing cell death. It is concluded that the hypothesis of the interaction of PrP[106-126] with membranes and formation of redox-sensitive and pH-modulated heterogeneous ion channels is consistent with: (a) PrP-induced changes in membrane fluidity and viscosity; (b) PrP-induced changes in Ca(2+) homeostasis (and does not exclude changes in endogenous Ca(2+) transport pathways and Cu(2+) homeostasis); (c) PrP role as an antioxidant; and (d) the PrP structural properties, i.e. beta sheets, protein aggregation, hydrophobicity, functional significance of specific amino acids (e.g. methionine, histidine) and regulation with low pH.
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Affiliation(s)
- J I Kourie
- Membrane Transport Group, Department of Chemistry, The Faculties, The Australian National University, ACT, 0200, Canberra, Australia.
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25
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Kourie JI, Farrelly PV, Henry CL. Channel activity of deamidated isoforms of prion protein fragment 106-126 in planar lipid bilayers. J Neurosci Res 2001; 66:214-20. [PMID: 11592116 DOI: 10.1002/jnr.1213] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Using the lipid bilayer technique, we have found that age-related derivatives, PrP[106-126] (L-Asp108) and PrP[106-126] (L-iso-Asp108), of the prion protein fragment 106-126 (PrP[106-126] (Asn108)) form heterogeneous ion channels. The deamidated isoforms, PrP[106-126] (L-Asp108) and PrP[106-126] (L-iso-Asp108), showed no enhanced propensity to form heterogeneous channels compared with PrP[106-126] (Asn108). One of the PrP[106-126] (L-Asp108)- and PrP[106-126] (L-iso-Asp108)-formed channels had three kinetic modes. The current-voltage (I-V) relationship of this channel, which had a reversal potential, E(rev), between -40 and -10 mV close to the equilibrium potential for K+ (E(K)-35 mV), exhibited a sigmoidal shape. The value of the maximal slope conductance (g(max)) was 62.5 pS at positive potentials between 0 and 140 mV. The probability (P(o)) and the frequency (F(o)) of the channel being open had inverted and bell-shaped curves, respectively, with a peak at membrane potential (V(m)) between -80 and +80 mV. The mean open and closed times (T(o) and T(c)) had inverted bell-shaped curves. The biophysical properties of PrP[106-126] (L-Asp108)- and PrP[106-126] (L-iso-Asp108)-formed channels and their response to Cu(2+) were similar to those of channels formed with PrP[106-126] (Asn108). Cu(2+) shifted the kinetics of the channel from being in the open state to a "burst state" in which rapid channel activities were separated by long durations of inactivity. The action of Cu(2+) on the open channel activity was both time-dependent and voltage-dependent. The fact that Cu(2+) induced changes in the kinetics of this channel with no changes in the conductance of the channel indicated that Cu(2+) binds at the mouth of the channel. Consistently with the hydrophilic and structural properties of PrP[106-126], the Cu(2+)-induced changes in the kinetic parameters of this channel suggest that the Cu(2+) binding site could be located at M(109) and H(111) of this prion fragment.
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Affiliation(s)
- J I Kourie
- Membrane Transport Group, Department of Chemistry, The Australian National University, Bldg. 33, Science Road, Canberra City, Act 0200, Australia.
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26
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Abstract
Prion diseases are transmissible neurodegenerative conditions that include Creutzfeldt-Jakob disease (CJD) in humans and bovine spongiform encephalopathy (BSE) and scrapie in animals. Prions appear to be composed principally or entirely of abnormal isoforms of a host-encoded glycoprotein, prion protein. Prion propagation involves recruitment of host cellular prion protein, composed primarily of alpha-helical structure, into a disease specific isoform rich in beta-sheet structure. The existence of multiple prion strains has been difficult to explain in terms of a protein-only infections agent, but recent studies suggest that strain specific phenotypes can be encoded by different prion protein conformations and glycosylation patterns. The ability of a protein to encode phenotypic information has important biological implications. The appearance of a novel human prion disease, variant CJD, and the clear experimental evidence that it is caused by exposure to BSE has highlighted the need to understand the molecular basis of prion propagation, pathogenesis, and the barriers limiting intermammalian transmission. It is unclear if a large epidemic of variant CJD will occur in the years ahead.
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Affiliation(s)
- J Collinge
- MRC Prion Unit and Department of Neurogenetics, Imperial College School of Medicine at St. Mary's, London, United Kingdom.
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27
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Abstract
Gliosis is one of the hallmarks of the prion diseases. Prion diseases are fatal neurodegenerative conditions of low incidence made famous by both the hypothesis that a protein acts as the infectious agent without involvement of nucleic acid and the speculative idea that a disease of cattle, BSE, has spread to humans from the ingestion of prion-infected beef. Despite these unproved hypotheses, the aetiology of the prion diseases remains unsolved. The rapid degenerative course of the disease is preceded by a long incubation period with little or no symptoms. The rapid neurodegeneration in the disease follows from increased deposition of an abnormal isoform of a normal neuronal protein. Co-incident with the appearance of this abnormal protein is the activation of large numbers of microglia. Studies in cell culture with both the abnormal prion protein and a peptide-mimic suggest that neuronal degeneration occurs because of two concurrent effects. First, there is a reduction in neuronal resistance to toxic insults and, second, there is an increase in the production of toxic substances such as reactive oxygen species by microglia and a decrease in glutamate clearance by astrocytes. Microglia activated by the abnormal form of the prion protein also release cytokines, which stimulate changes in astrocytes such as proliferation. The implication of this is that microglia may play a major role in initiating the pathological changes in prion disease. This review discusses the role of microglia in these changes.
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Affiliation(s)
- D R Brown
- Department of Biochemistry, Cambridge University, Cambridge, CB2 1QW, United Kingdom.
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Aguzzi A. Recent developments in the pathogenesis, diagnosis, and therapy of prion diseases. DIALOGUES IN CLINICAL NEUROSCIENCE 2001. [PMID: 22034459 PMCID: PMC3181643 DOI: 10.31887/dcns.2001.3.1/aaguzzi] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Prions continue to pose a formidable challenge to life sciences. While human prion diseases are still rare, the incidence of a new variant of Creutzfeldt-Jakob disease in the United Kingdom is increasing exponentially - raising fears that it might develop into a major epidemic. This disease is likely to represent the result of human infection with bovine prions. Therefore, understanding how prions replicate and damage the brain, and how their action may be possibly counteracted, has become a major public health issue. Here I examine some current hypotheses concerning the links between bovine and human prion diseases, and the mechanisms by which prions reach and damage the central nervous system after having entered the body at extracerebral sites.
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Abstract
Although human prion diseases are rare, the incidence of 'new variant' Creutzfeldt-Jakob disease in the United Kingdom is increasing exponentially. Given that this disease is probably the result of infection with bovine prions, understanding how prions replicate--and how to counteract their action--has become a central issue for public health. What are the links between the bovine and human prion diseases, and how do prions reach and damage the central nervous system?
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Affiliation(s)
- A Aguzzi
- Institute of Neuropathology, University of Zurich, Schmelzbergstrasse 12, CH-8091 Zurich, Switzerland.
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30
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Abstract
Prion diseases are neurodegenerative disorders associated with a conformational change in the normal cellular isoform of the prion protein, PrP(C), to an abnormal scrapie isoform, PrP(SC). Unlike the alpha-helical PrP(C), the protease-resistant core of PrP(SC) is predominantly beta-sheet and possesses a tendency to polymerize into amyloid fibrils. We performed experiments with two synthetic human prion peptides, PrP(106-126) and PrP(127-147), to determine how peptide structure affects neurotoxicity and protein-membrane interactions. Peptide solutions possessing beta-sheet and amyloid structures were neurotoxic to PC12 cells in vitro and bound with measurable affinities to cholesterol-rich phospholipid membranes at ambient conditions, but peptide solutions lacking stable beta-sheet structures and amyloid content were nontoxic and possessed less than one tenth of the binding affinities of the amyloid-containing peptides. Regardless of structure, the peptide binding affinities to cholesterol-depleted membranes were greatly reduced. These results suggest that the beta-sheet and amyloid structures of the prion peptides give rise to their toxicity and membrane binding affinities and that membrane binding affinity, especially in cholesterol-rich environments, may be related to toxicity. Our results may have significance in understanding the role of the fibrillogenic cerebral deposits associated with some of the prion diseases in neurodegeneration and may have implications for other amyloidoses.
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Affiliation(s)
- D L Rymer
- Department of Chemical Engineering, Texas A&M University, College Station, Texas 77843-3122, USA
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31
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Deli MA, Sakaguchi S, Nakaoke R, Abrahám CS, Takahata H, Kopacek J, Shigematsu K, Katamine S, Niwa M. PrP fragment 106-126 is toxic to cerebral endothelial cells expressing PrP(C). Neuroreport 2000; 11:3931-6. [PMID: 11117517 DOI: 10.1097/00001756-200011270-00064] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
A hydrophobic, fibrillogenic peptide fragment of human prion protein (PrP106-126) had in vitro toxicity to neurons expressing cellular prion protein (PrP(C)). In this study, we proved that primary cultures of mouse cerebral endothelial cells (MCEC) express PrP(C). Incubation of MCEC with PrP106-126 (25-200 microM) caused a dose-dependent toxicity assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, lactate dehydrogenase release, bis-benzimide staining for nuclear morphology, and trypan blue exclusion test. Pentosan polysulphate (50-100 microg/ml), a drug effective in scrapie prophylaxis, dose-dependently attenuated the injury. MCEC cultures from mice homogenous for the disrupted PrP gene were resistant to the toxicity of PrP106-126. In conclusion, cerebral endothelium expressing PrP(C) may be directly damaged during spongiform encephalopathies.
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Affiliation(s)
- M A Deli
- Department of Pharmacology 1, School of Medicine, Nagasaki University, Japan
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32
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Abstract
Using the lipid bilayer technique we have optimized the recording conditions and confirmed that PrP[106-126] (KTNMKHMAGAAAAGAVVGGLG) forms single ion channels. Based on the conductance and kinetic parameters of the single channel currents recorded in 250/50 mM KCl cis/trans we have found that the PrP[106-126]-formed heterogeneous cation channels that differ in their conductance and kinetic properties. The most frequently observed PrP[106-126]-formed single cation channels were those of: (a) a GSSH- and TEA-sensitive channel with fast kinetics (n = 47). The current-voltage (I-V) relationship of this channel, that has a reversal potential E(rev) of -33 mV close to the equilibrium potential for K(+) (E(K) -35 mV), exhibited inward and outward rectification. The values of the maximal slope conductance (g(max)) were 138 and 141 pS at positive and negative potentials, respectively. The values of the permeability ratios were 1.0:0.87:0.72:0.49:0.41 for K(+) > Rb(+) > Na(+) > Cs(+) > Li(+) respectively. The probability of the channel being open (P(o)) and the frequency (F(o)) had bell-shaped curves with a peak at membrane potential (V(m)) between -10 and -5 mV whereas the mean open and closed times (T(o) and T(c)) had inverted bell-shaped curves; (b) a 4'-4'-dithiodipyridin (DTT)-sensitive channel with slow kinetics (n = 32). The I-V relationship of this channel that had an E(rev) of -35 mV and a g(max) of 41 pS at positive V(m) was non-linear. The parameter P(o) increased at positive V(m) to 0.6-0.7 at +80 mV. F(o) had an asymmetrical bell-shaped curve with a peak of 314 events/sec at -80 mV. The values of T(o) and T(c) were 312 and 164 msec at +120 mV, respectively; (c) a large channel (n = 24 channels) that had five equally spaced subconductances showed time-dependent fast and slow transitions at positive and negative V(m), respectively. The inactivation ratio I(ss)/I(i) was V(m) dependent and described by a bell-shape. The I-V relationship of this channel that had a E(rev) of -22 mV was non linear. The value of g(max) was 900 and 1444 pS at positive and negative V(m)s, respectively. The value of P(o) was 0.6 at negative V(m)s between -160 and -80 mV and 0.23 at +140 mV. F(o) increased from 22 events/sec at -160 mV to 80-100 events/sec at between +80 and +100 mV. T(o) decreased from 375 msec between -160 and -80 mV to 1-2 msec at V(m)s between 0 and +160 mV. In contrast, T(c) decreased from 160-240 msec at membrane voltages (V(m)s) between -160 and -80 mV. The biophysical properties of these channels indicate that they are capable of modifying cellular functions via modification of V(m) and electrolyte homeostasis of the cell.
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Affiliation(s)
- J I Kourie
- Membrane Transport Group, Department of Chemistry, The Faculties, The Australian National University, Canberra City, Australia.
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33
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Abstract
The long-term, progressive decay of the central nervous system typifies prion diseases, a group of rare, transmissible maladies affecting humans, sheep, cattle and some other types of mammal. Little is known about the early molecular events in its pathogenesis but the diverse roles of PrP, the prion protein, in its destructive action have recently been re-emphasised.
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Affiliation(s)
- J Hope
- Institute for Animal Health, Berkshire RG20 7NN, Compton, UK.
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34
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Manunta M, Kunz B, Sandmeier E, Christen P, Schindler H. Reported channel formation by prion protein fragment 106-126 in planar lipid bilayers cannot be reproduced. FEBS Lett 2000; 474:255-6. [PMID: 10896484 DOI: 10.1016/s0014-5793(00)01603-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Monoi H, Futaki S, Kugimiya S, Minakata H, Yoshihara K. Poly-L-glutamine forms cation channels: relevance to the pathogenesis of the polyglutamine diseases. Biophys J 2000; 78:2892-9. [PMID: 10827970 PMCID: PMC1300875 DOI: 10.1016/s0006-3495(00)76830-5] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
We report that long-chain poly-L-glutamine forms cation-selective channels when incorporated into artificial planar lipid bilayer membranes. The channel was permeable to alkali cations and H(+) ions and virtually impermeable to anions; the selectivity sequence based on the single-channel conductance was H(+) >> Cs(+) > K(+) > Na(+). The cation channel was characterized by long-lived open states (often lasting for several minutes to tens of minutes) interrupted by brief closings. The appearance of the channel depended critically on the length of polyglutamine chains; ion channels were observed with 40-residue stretches, whereas no significant conductance changes were detected with 29-residue tracts. The channel-forming threshold length of poly-L-glutamine was thus between 29 and 40 residues. A molecular mechanics calculation suggests a mu-helix (. Biophys. J. 69:1130-1141) as a candidate molecular structure of the channel. The channel-forming nature of long-chain poly-L-glutamine may provide a clue to the elucidation of the pathogenetic mechanism of the polyglutamine diseases, a group of inherited neurodegenerative disorders including Huntington's disease.
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Affiliation(s)
- H Monoi
- Research Institute of Neurodegenerative Diseases, Sendai 980-0871, Japan.
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36
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Semenza G. From the handling editor. FEBS Lett 2000; 466:208. [PMID: 10648845 DOI: 10.1016/s0014-5793(99)01783-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Affiliation(s)
- G Semenza
- Swiss Federal Institute of Technology, Biochemistry, ETH-Zentrum, CH-8092, Zurich, Switzerland
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37
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Forloni G, Salmona M, Bugiani O, Tagliavini F. Comment on: Neurotoxicity of prion peptide 106-126 not confirmed, by Beat Kunz, Erika Sandmeier, Philipp Christen. FEBS Letters 485 (1999) 65-68. FEBS Lett 2000; 466:205-6; discussion 207. [PMID: 10648843 DOI: 10.1016/s0014-5793(99)01781-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- G Forloni
- Istituto di Ricerche Farmacologiche 'Mario Negri', Via Eritrea 62, 20157, Milan, Italy.
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