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Olech M. Conventional and State-of-the-Art Detection Methods of Bovine Spongiform Encephalopathy (BSE). Int J Mol Sci 2023; 24:ijms24087135. [PMID: 37108297 PMCID: PMC10139118 DOI: 10.3390/ijms24087135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Revised: 04/08/2023] [Accepted: 04/09/2023] [Indexed: 04/29/2023] Open
Abstract
Bovine spongiform encephalopathy (BSE) is a fatal neurodegenerative disease that belongs to a group of diseases known as transmissible spongiform encephalopathies (TSEs). It is believed that the infectious agent responsible for prion diseases is abnormally folded prion protein (PrPSc), which derives from a normal cellular protein (PrPC), which is a cell surface glycoprotein predominantly expressed in neurons. There are three different types of BSE, the classical BSE (C-type) strain and two atypical strains (H-type and L-type). BSE is primarily a disease of cattle; however, sheep and goats also can be infected with BSE strains and develop a disease clinically and pathogenically indistinguishable from scrapie. Therefore, TSE cases in cattle and small ruminants require discriminatory testing to determine whether the TSE is BSE or scrapie and to discriminate classical BSE from the atypical H- or L-type strains. Many methods have been developed for the detection of BSE and have been reported in numerous studies. Detection of BSE is mainly based on the identification of characteristic lesions or detection of the PrPSc in the brain, often by use of their partial proteinase K resistance properties. The objective of this paper was to summarize the currently available methods, highlight their diagnostic performance, and emphasize the advantages and drawbacks of the application of individual tests.
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Affiliation(s)
- Monika Olech
- Department of Pathology, National Veterinary Research Institute, 24-100 Puławy, Poland
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2
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Castle AR, Wohlgemuth S, Arce L, Westaway D. Investigating CRISPR/Cas9 gene drive for production of disease-preventing prion gene alleles. PLoS One 2022; 17:e0269342. [PMID: 35671288 PMCID: PMC9173614 DOI: 10.1371/journal.pone.0269342] [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: 03/27/2022] [Accepted: 05/18/2022] [Indexed: 11/29/2022] Open
Abstract
Prion diseases are a group of fatal neurodegenerative disorders that includes chronic wasting disease, which affects cervids and is highly transmissible. Given that chronic wasting disease prevalence exceeds 30% in some endemic areas of North America, and that eventual transmission to other mammalian species, potentially including humans, cannot be ruled out, novel control strategies beyond population management via hunting and/or culling must be investigated. Prion diseases depend upon post-translational conversion of the cellular prion protein, encoded by the Prnp gene, into a disease-associated conformation; ablation of cellular prion protein expression, which is generally well-tolerated, eliminates prion disease susceptibility entirely. Inspired by demonstrations of gene drive in caged mosquito species, we aimed to test whether a CRISPR/Cas9-based gene drive mechanism could, in principle, promote the spread of a null Prnp allele among mammalian populations. First, we showed that transient co-expression of Cas9 and Prnp-directed guide RNAs in RK13 cells generates indels within the Prnp open-reading frame, indicating that repair of Cas9-induced double-strand breaks by non-homologous end-joining had taken place. Second, we integrated a ~1.2 kb donor DNA sequence into the Prnp open-reading frame in N2a cells by homology-directed repair following Cas9-induced cleavages and confirmed that integration occurred precisely in most cases. Third, we demonstrated that electroporation of Cas9/guide RNA ribonucleoprotein complexes into fertilised mouse oocytes resulted in pups with a variety of disruptions to the Prnp open reading frame, with a new coisogenic line of Prnp-null mice obtained as part of this work. However, a technical challenge in obtaining expression of Cas9 in the male germline prevented implementation of a complete gene drive mechanism in mice.
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Affiliation(s)
- Andrew R. Castle
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
- Department of Medicine, University of Alberta, Edmonton, Alberta, Canada
| | - Serene Wohlgemuth
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
- Department of Medicine, University of Alberta, Edmonton, Alberta, Canada
| | - Luis Arce
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
| | - David Westaway
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
- Department of Medicine, University of Alberta, Edmonton, Alberta, Canada
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
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3
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Lyon A, Mays CE, Borriello F, Telling GC, Soto C, Pritzkow S. Application of PMCA to screen for prion infection in a human cell line used to produce biological therapeutics. Sci Rep 2019; 9:4847. [PMID: 30890734 PMCID: PMC6424962 DOI: 10.1038/s41598-019-41055-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Accepted: 02/01/2019] [Indexed: 12/11/2022] Open
Abstract
Advances in biotechnology have led to the development of a number of biological therapies for the treatment of diverse human diseases. Since these products may contain or are made using human or animal (e.g. cattle) derived materials, it is crucial to test their safety by ensuring the absence of infectious agents; specifically prions, which are highly resilient to elimination and produce fatal diseases in humans. Many cases of iatrogenic Creutzfeldt-Jakob disease have been caused by the use of biological materials (e.g. human growth hormone) contaminated with prions. For this reason, it is important to screen cells and biological materials for the presence of prions. Here we show the utility of the Protein Misfolding Cyclic Amplification (PMCA) technology as a screening tool for the presence of human (vCJD) and bovine (BSE) prions in a human cell therapy product candidate. First, we demonstrated the sensitivity of PMCA to detect a single cell infected with prions. For these experiments, we used RKM7 cells chronically infected with murine RML prions. Serial dilutions of an infected cell culture showed that PMCA enabled prion amplification from a sample comprised of only one cell. Next, we determined that PMCA performance was robust and uncompromised by the spiking of large quantities of uninfected cells into the reaction. Finally, to demonstrate the practical application of this technology, we analyzed a human cell line being developed for therapeutic use and found it to be PMCA-negative for vCJD and BSE prions. Our findings demonstrate that the PMCA technology has unparalleled sensitivity and specificity for the detection of prions, making it an ideal quality control procedure in the production of biological therapeutics.
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Affiliation(s)
- Adam Lyon
- Mitchell Center for Alzheimer's Disease and Related Brain Disorders, University of Texas McGovern Medical School, Houston, TX, 77030, USA
| | - Charles E Mays
- Mitchell Center for Alzheimer's Disease and Related Brain Disorders, University of Texas McGovern Medical School, Houston, TX, 77030, USA
| | - Frank Borriello
- Alloplex Biotherapeutics, Inc., 21 Erie Street, Cambridge, MA, 02139, USA
| | - Glenn C Telling
- Prion Research Center, Colorado State University, Colorado, USA
| | - Claudio Soto
- Mitchell Center for Alzheimer's Disease and Related Brain Disorders, University of Texas McGovern Medical School, Houston, TX, 77030, USA
| | - Sandra Pritzkow
- Mitchell Center for Alzheimer's Disease and Related Brain Disorders, University of Texas McGovern Medical School, Houston, TX, 77030, USA.
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4
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In vitro Modeling of Prion Strain Tropism. Viruses 2019; 11:v11030236. [PMID: 30857283 PMCID: PMC6466166 DOI: 10.3390/v11030236] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Revised: 03/04/2019] [Accepted: 03/05/2019] [Indexed: 12/30/2022] Open
Abstract
Prions are atypical infectious agents lacking genetic material. Yet, various strains have been isolated from animals and humans using experimental models. They are distinguished by the resulting pattern of disease, including the localization of PrPsc deposits and the spongiform changes they induce in the brain of affected individuals. In this paper, we discuss the emerging use of cellular and acellular models to decipher the mechanisms involved in the strain-specific targeting of distinct brain regions. Recent studies suggest that neuronal cultures, protein misfolding cyclic amplification, and combination of both approaches may be useful to explore this under-investigated but central domain of the prion field.
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5
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Bourkas MEC, Arshad H, Al-Azzawi ZAM, Halgas O, Shikiya RA, Mehrabian M, Schmitt-Ulms G, Bartz JC, Watts JC. Engineering a murine cell line for the stable propagation of hamster prions. J Biol Chem 2019; 294:4911-4923. [PMID: 30705093 DOI: 10.1074/jbc.ra118.007135] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Revised: 01/30/2019] [Indexed: 01/23/2023] Open
Abstract
Prions are infectious protein aggregates that cause several fatal neurodegenerative diseases. Prion research has been hindered by a lack of cellular paradigms for studying the replication of prions from different species. Although hamster prions have been widely used to study prion replication in animals and within in vitro amplification systems, they have proved challenging to propagate in cultured cells. Because the murine catecholaminergic cell line CAD5 is susceptible to a diverse range of mouse prion strains, we hypothesized that it might also be capable of propagating nonmouse prions. Here, using CRISPR/Cas9-mediated genome engineering, we demonstrate that CAD5 cells lacking endogenous mouse PrP expression (CAD5-PrP-/- cells) can be chronically infected with hamster prions following stable expression of hamster PrP. When exposed to the 263K, HY, or 139H hamster prion strains, these cells stably propagated high levels of protease-resistant PrP. Hamster prion replication required absence of mouse PrP, and hamster PrP inhibited the propagation of mouse prions. Cellular homogenates from 263K-infected cells exhibited prion seeding activity in the RT-QuIC assay and were infectious to naïve cells expressing hamster PrP. Interestingly, murine N2a neuroblastoma cells ablated for endogenous PrP expression were susceptible to mouse prions, but not hamster prions upon expression of cognate PrP, suggesting that CAD5 cells either possess cellular factors that enhance or lack factors that restrict the diversity of prion strains that can be propagated. We conclude that transfected CAD5-PrP-/- cells may be a useful tool for assessing the biology of prion strains and dissecting the mechanism of prion replication.
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Affiliation(s)
- Matthew E C Bourkas
- From the Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario, Canada M5T 0S8.,Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada M5T 0S8
| | - Hamza Arshad
- From the Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario, Canada M5T 0S8.,Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada M5T 0S8
| | - Zaid A M Al-Azzawi
- From the Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario, Canada M5T 0S8.,Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada M5T 0S8
| | - Ondrej Halgas
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada M5T 0S8
| | - Ronald A Shikiya
- Department of Medical Microbiology and Immunology, Creighton University, Omaha, Nebraska, 68178
| | - Mohadeseh Mehrabian
- From the Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario, Canada M5T 0S8.,Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada M5T 0S8, and
| | - Gerold Schmitt-Ulms
- From the Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario, Canada M5T 0S8.,Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada M5T 0S8, and
| | - Jason C Bartz
- Department of Medical Microbiology and Immunology, Creighton University, Omaha, Nebraska, 68178
| | - Joel C Watts
- From the Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario, Canada M5T 0S8, .,Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada M5T 0S8
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6
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Kurt TD, Aguilar-Calvo P, Jiang L, Rodriguez JA, Alderson N, Eisenberg DS, Sigurdson CJ. Asparagine and glutamine ladders promote cross-species prion conversion. J Biol Chem 2017; 292:19076-19086. [PMID: 28931606 PMCID: PMC5704488 DOI: 10.1074/jbc.m117.794107] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Revised: 09/01/2017] [Indexed: 11/06/2022] Open
Abstract
Prion transmission between species is governed in part by primary sequence similarity between the infectious prion aggregate, PrPSc, and the cellular prion protein of the host, PrPC A puzzling feature of prion formation is that certain PrPC sequences, such as that of bank vole, can be converted by a remarkably broad array of different mammalian prions, whereas others, such as rabbit, show robust resistance to cross-species prion conversion. To examine the structural determinants that confer susceptibility or resistance to prion conversion, we systematically tested over 40 PrPC variants of susceptible and resistant PrPC sequences in a prion conversion assay. Five key residue positions markedly impacted prion conversion, four of which were in steric zipper segments where side chains from amino acids tightly interdigitate in a dry interface. Strikingly, all five residue substitutions modulating prion conversion involved the gain or loss of an asparagine or glutamine residue. For two of the four positions, Asn and Gln residues were not interchangeable, revealing a strict requirement for either an Asn or Gln residue. Bank voles have a high number of Asn and Gln residues and a high Asn:Gln ratio. These findings suggest that a high number of Asn and Gln residues at specific positions may stabilize β-sheets and lower the energy barrier for cross-species prion transmission, potentially because of hydrogen bond networks from side chain amides forming extended Asn/Gln ladders. These data also suggest that multiple PrPC segments containing Asn/Gln residues may act in concert along a replicative interface to promote prion conversion.
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Affiliation(s)
- Timothy D Kurt
- From the Departments of Pathology and Medicine, University of California at San Diego, La Jolla, California 92093
| | - Patricia Aguilar-Calvo
- From the Departments of Pathology and Medicine, University of California at San Diego, La Jolla, California 92093
| | - Lin Jiang
- the Department of Neurology, UCLA, Los Angeles, California 90095, and
| | - José A Rodriguez
- the UCLA-DOE Institute, Howard Hughes Medical Institute, Los Angeles, California 90095
- the Molecular Biology Institute
- the Department of Chemistry and Biochemistry, and
| | - Nazilla Alderson
- From the Departments of Pathology and Medicine, University of California at San Diego, La Jolla, California 92093
| | - David S Eisenberg
- the UCLA-DOE Institute, Howard Hughes Medical Institute, Los Angeles, California 90095
- the Molecular Biology Institute
| | - Christina J Sigurdson
- From the Departments of Pathology and Medicine, University of California at San Diego, La Jolla, California 92093,
- the Department of Pathology, Immunology, and Microbiology, University of California at Davis, Davis, California 95616
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7
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Dassanayake RP, Zhuang D, Truscott TC, Madsen-Bouterse SA, O'Rourke KI, Schneider DA. A transfectant RK13 cell line permissive to classical caprine scrapie prion propagation. Prion 2017; 10:153-64. [PMID: 27216989 DOI: 10.1080/19336896.2016.1166324] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
To assess scrapie infectivity associated with caprine-origin tissues, bioassay can be performed using kids, lambs or transgenic mice expressing caprine or ovine prion (PRNP) alleles, but the incubation periods are fairly long. Although several classical ovine scrapie prion permissive cell lines with the ability to detect brain-derived scrapie prion have been available, no classical caprine scrapie permissive cell line is currently available. Therefore, the aims of this study were to generate a rabbit kidney epithelial cell line (RK13) stably expressing caprine wild-type PRNP (cpRK13) and then to assess permissiveness of cpRK13 cells to classical caprine scrapie prion propagation. The cpRK13 and plasmid control RK13 (pcRK13) cells were incubated with brain-derived classical caprine scrapie inocula prepared from goats or ovinized transgenic mice (Tg338, express ovine VRQ allele) infected with caprine scrapie. Significant PrP(Sc) accumulation, which is indicative of scrapie prion propagation, was detected by TSE ELISA and immunohistochemistry in cpRK13 cells inoculated with classical caprine scrapie inocula. Western blot analysis revealed the typical proteinase K-resistant 3 PrP(res) isoforms in the caprine scrapie prion inoculated cpRK13 cell lysate. Importantly, PrP(Sc) accumulation was not detected in similarly inoculated pcRK13 cells, whether by TSE ELISA, immunohistochemistry, or western blot. These findings suggest that caprine scrapie prions can be propagated in cpRK13 cells, thus this cell line may be a useful tool for the assessment of classical caprine prions in the brain tissues of goats.
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Affiliation(s)
- Rohana P Dassanayake
- a Department of Veterinary Microbiology and Pathology , College of Veterinary Medicine, Washington State University , Pullman , WA , USA
| | - Dongyue Zhuang
- b Animal Disease Research Unit, Agricultural Research Service , U.S. Department of Agriculture , Pullman , WA , USA
| | - Thomas C Truscott
- b Animal Disease Research Unit, Agricultural Research Service , U.S. Department of Agriculture , Pullman , WA , USA
| | - Sally A Madsen-Bouterse
- a Department of Veterinary Microbiology and Pathology , College of Veterinary Medicine, Washington State University , Pullman , WA , USA
| | - Katherine I O'Rourke
- a Department of Veterinary Microbiology and Pathology , College of Veterinary Medicine, Washington State University , Pullman , WA , USA
| | - David A Schneider
- a Department of Veterinary Microbiology and Pathology , College of Veterinary Medicine, Washington State University , Pullman , WA , USA ;,b Animal Disease Research Unit, Agricultural Research Service , U.S. Department of Agriculture , Pullman , WA , USA
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8
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Shikiya RA, Langenfeld KA, Eckland TE, Trinh J, Holec SAM, Mathiason CK, Kincaid AE, Bartz JC. PrPSc formation and clearance as determinants of prion tropism. PLoS Pathog 2017; 13:e1006298. [PMID: 28355274 PMCID: PMC5386299 DOI: 10.1371/journal.ppat.1006298] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Revised: 04/10/2017] [Accepted: 03/16/2017] [Indexed: 11/19/2022] Open
Abstract
Prion strains are characterized by strain-specific differences in neuropathology but can also differ in incubation period, clinical disease, host-range and tissue tropism. The hyper (HY) and drowsy (DY) strains of hamster-adapted transmissible mink encephalopathy (TME) differ in tissue tropism and susceptibility to infection by extraneural routes of infection. Notably, DY TME is not detected in the secondary lymphoreticular system (LRS) tissues of infected hosts regardless of the route of inoculation. We found that similar to the lymphotropic strain HY TME, DY TME crosses mucosal epithelia, enters draining lymphatic vessels in underlying laminae propriae, and is transported to LRS tissues. Since DY TME causes disease once it enters the peripheral nervous system, the restriction in DY TME pathogenesis is due to its inability to establish infection in LRS tissues, not a failure of transport. To determine if LRS tissues can support DY TME formation, we performed protein misfolding cyclic amplification using DY PrPSc as the seed and spleen homogenate as the source of PrPC. We found that the spleen environment can support DY PrPSc formation, although at lower rates compared to lymphotropic strains, suggesting that the failure of DY TME to establish infection in the spleen is not due to the absence of a strain-specific conversion cofactor. Finally, we provide evidence that DY PrPSc is more susceptible to degradation when compared to PrPSc from other lymphotrophic strains. We hypothesize that the relative rates of PrPSc formation and clearance can influence prion tropism.
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Affiliation(s)
- Ronald A. Shikiya
- Department of Medical Microbiology and Immunology, Creighton University, Omaha, Nebraska, United States of America
| | - Katie A. Langenfeld
- Department of Medical Microbiology and Immunology, Creighton University, Omaha, Nebraska, United States of America
| | - Thomas E. Eckland
- Department of Medical Microbiology and Immunology, Creighton University, Omaha, Nebraska, United States of America
| | - Jonathan Trinh
- Department of Medical Microbiology and Immunology, Creighton University, Omaha, Nebraska, United States of America
| | - Sara A. M. Holec
- Department of Medical Microbiology and Immunology, Creighton University, Omaha, Nebraska, United States of America
| | - Candace K. Mathiason
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, United States of America
| | - Anthony E. Kincaid
- Department of Medical Microbiology and Immunology, Creighton University, Omaha, Nebraska, United States of America
- Department of Pharmacy Science, 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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9
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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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10
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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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11
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Kurt TD, Jiang L, Fernández-Borges N, Bett C, Liu J, Yang T, Spraker TR, Castilla J, Eisenberg D, Kong Q, Sigurdson CJ. Human prion protein sequence elements impede cross-species chronic wasting disease transmission. J Clin Invest 2015; 125:1485-96. [PMID: 25705888 DOI: 10.1172/jci79408] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Accepted: 01/08/2015] [Indexed: 11/17/2022] Open
Abstract
Chronic wasting disease (CWD) is a fatal prion disease of North American deer and elk and poses an unclear risk for transmission to humans. Human exposure to CWD occurs through hunting activities and consumption of venison from prion-infected animals. Although the amino acid residues of the prion protein (PrP) that prevent or permit human CWD infection are unknown, NMR-based structural studies suggest that the β2-α2 loop (residues 165-175) may impact species barriers. Here we sought to define PrP sequence determinants that affect CWD transmission to humans. We engineered transgenic mice that express human PrP with four amino acid substitutions that result in expression of PrP with a β2-α2 loop (residues 165-175) that exactly matches that of elk PrP. Compared with transgenic mice expressing unaltered human PrP, mice expressing the human-elk chimeric PrP were highly susceptible to elk and deer CWD prions but were concurrently less susceptible to human Creutzfeldt-Jakob disease prions. A systematic in vitro survey of amino acid differences between humans and cervids identified two additional residues that impacted CWD conversion of human PrP. This work identifies amino acids that constitute a substantial structural barrier for CWD transmission to humans and helps illuminate the molecular requirements for cross-species prion transmission.
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12
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Kim DH, Lee HM, Ryou C. Evaluation of infective property of recombinant prion protein amyloids in cultured cells overexpressing cellular prion protein. J Korean Med Sci 2014; 29:1604-9. [PMID: 25469058 PMCID: PMC4248579 DOI: 10.3346/jkms.2014.29.12.1604] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Accepted: 11/06/2014] [Indexed: 11/22/2022] Open
Abstract
Misfolded isoform of prion protein (PrP), termed scrapie PrP (PrP(Sc)), tends to aggregate into various fibril forms. Previously, we reported various conditions that affect aggregation of recombinant PrP into amyloids. Because amyloidogenesis of PrP is closely associated with transmissible spongiform encephalopathies such as Creutzfeldt-Jakob disease in humans, we investigated infectivity of recombinant PrP amyloids generated in vitro. Using cultured cell lines which overexpress cellular PrP of different species, we measured the level of de novo synthesized PrP(Sc) in cells inoculated with recombinant mouse PrP amyloids. While PrP-overexpressing cells were susceptible to mouse-adapted scrapie prions used as the positive control, demonstrating the species barrier effect, infection with amyloids made of truncated recombinant PrP (PrP[89-230]) failed to form and propagate PrP(Sc) even in the cells that express mouse cellular PrP. This suggests that infectivity of PrP amyloids generated in vitro is different from that of natural prions. Recombinant PrP (89-230) amyloids tested in the current study retain no or a minute level, if any, of prion infectivity.
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Affiliation(s)
- Dae-Hwan Kim
- Department of Pharmacy, College of Pharmacy and Institute of Pharmaceutical Science and Technology, Hanyang University, Ansan, Korea
| | - Hye-Mi Lee
- Department of Pharmacy, College of Pharmacy and Institute of Pharmaceutical Science and Technology, Hanyang University, Ansan, Korea
| | - Chongsuk Ryou
- Department of Pharmacy, College of Pharmacy and Institute of Pharmaceutical Science and Technology, Hanyang University, Ansan, Korea
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13
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Protocol for further laboratory investigations into the distribution of infectivity of Atypical BSE. EFSA J 2014. [DOI: 10.2903/j.efsa.2014.3798] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
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14
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Lacroux C, Comoy E, Moudjou M, Perret-Liaudet A, Lugan S, Litaise C, Simmons H, Jas-Duval C, Lantier I, Béringue V, Groschup M, Fichet G, Costes P, Streichenberger N, Lantier F, Deslys JP, Vilette D, Andréoletti O. Preclinical detection of variant CJD and BSE prions in blood. PLoS Pathog 2014; 10:e1004202. [PMID: 24945656 PMCID: PMC4055790 DOI: 10.1371/journal.ppat.1004202] [Citation(s) in RCA: 81] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Accepted: 05/01/2014] [Indexed: 11/19/2022] Open
Abstract
The emergence of variant Creutzfeldt Jakob Disease (vCJD) is considered a likely consequence of human dietary exposure to Bovine Spongiform Encephalopathy (BSE) agent. More recently, secondary vCJD cases were identified in patients transfused with blood products prepared from apparently healthy donors who later went on to develop the disease. As there is no validated assay for detection of vCJD/BSE infected individuals the prevalence of the disease in the population remains uncertain. In that context, the risk of vCJD blood borne transmission is considered as a serious concern by health authorities. In this study, appropriate conditions and substrates for highly efficient and specific in vitro amplification of vCJD/BSE agent using Protein Misfolding Cyclic Amplification (PMCA) were first identified. This showed that whatever the origin (species) of the vCJD/BSE agent, the ovine Q171 PrP substrates provided the best amplification performances. These results indicate that the homology of PrP amino-acid sequence between the seed and the substrate is not the crucial determinant of the vCJD agent propagation in vitro. The ability of this method to detect endogenous vCJD/BSE agent in the blood was then defined. In both sheep and primate models of the disease, the assay enabled the identification of infected individuals in the early preclinical stage of the incubation period. Finally, sample panels that included buffy coat from vCJD affected patients and healthy controls were tested blind. The assay identified three out of the four tested vCJD affected patients and no false positive was observed in 141 healthy controls. The negative results observed in one of the tested vCJD cases concurs with results reported by others using a different vCJD agent blood detection assay and raises the question of the potential absence of prionemia in certain patients.
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Affiliation(s)
- Caroline Lacroux
- UMR INRA ENVT 1225, Interactions Hôtes Agents Pathogènes, Ecole Nationale Vétérinaire de Toulouse, Toulouse, France
| | - Emmanuel Comoy
- CEA, Institute of Emerging Diseases and Innovative Therapies (iMETI), Division of Prions and Related Diseases (SEPIA), Fontenay-aux-Roses, France
| | - Mohammed Moudjou
- UR892 Virologie et Immunologie Moléculaires Centre de Recherche de Jouy-en-Josas, Jouy-en-Josas, France
| | - Armand Perret-Liaudet
- Hospices Civils de Lyon –Laboratoire Diagnostic Maladies à Prions; CNRS, INSERM, UCB Lyon1, Centre de Recherche en Neurosciences de Lyon, BioRan, Bron, France
| | - Séverine Lugan
- UMR INRA ENVT 1225, Interactions Hôtes Agents Pathogènes, Ecole Nationale Vétérinaire de Toulouse, Toulouse, France
| | - Claire Litaise
- UMR INRA ENVT 1225, Interactions Hôtes Agents Pathogènes, Ecole Nationale Vétérinaire de Toulouse, Toulouse, France
| | - Hugh Simmons
- VLA Weybridge, ASU, New Haw, Addlestone, Surrey, United Kingdom
| | | | - Isabelle Lantier
- INRA, UMR 1282 Infectiologie et Santé Publique, Nouzilly, France
| | - Vincent Béringue
- UR892 Virologie et Immunologie Moléculaires Centre de Recherche de Jouy-en-Josas, Jouy-en-Josas, France
| | - Martin Groschup
- Friedrich-Loeffler-Institut, Greifswald, Insel Riems, Germany
| | - Guillaume Fichet
- UR892 Virologie et Immunologie Moléculaires Centre de Recherche de Jouy-en-Josas, Jouy-en-Josas, France
- Franklab, Montigny-le-Bretonneux, France
| | - Pierrette Costes
- UMR INRA ENVT 1225, Interactions Hôtes Agents Pathogènes, Ecole Nationale Vétérinaire de Toulouse, Toulouse, France
| | - Nathalie Streichenberger
- UR892 Virologie et Immunologie Moléculaires Centre de Recherche de Jouy-en-Josas, Jouy-en-Josas, France
| | - Frederic Lantier
- INRA, UMR 1282 Infectiologie et Santé Publique, Nouzilly, France
| | - Jean Philippe Deslys
- CEA, Institute of Emerging Diseases and Innovative Therapies (iMETI), Division of Prions and Related Diseases (SEPIA), Fontenay-aux-Roses, France
| | - Didier Vilette
- UMR INRA ENVT 1225, Interactions Hôtes Agents Pathogènes, Ecole Nationale Vétérinaire de Toulouse, Toulouse, France
| | - Olivier Andréoletti
- UMR INRA ENVT 1225, Interactions Hôtes Agents Pathogènes, Ecole Nationale Vétérinaire de Toulouse, Toulouse, France
- * E-mail:
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15
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Kurt TD, Jiang L, Bett C, Eisenberg D, Sigurdson CJ. A proposed mechanism for the promotion of prion conversion involving a strictly conserved tyrosine residue in the β2-α2 loop of PrPC. J Biol Chem 2014; 289:10660-10667. [PMID: 24596090 DOI: 10.1074/jbc.m114.549030] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The transmission of infectious prions into different host species requires compatible prion protein (PrP) primary structures, and even one heterologous residue at a pivotal position can block prion infection. Mapping the key amino acid positions that govern cross-species prion conversion has not yet been possible, although certain residue positions have been identified as restrictive, including residues in the β2-α2 loop region of PrP. To further define how β2-α2 residues impact conversion, we investigated residue substitutions in PrP(C) using an in vitro prion conversion assay. Within the β2-α2 loop, a tyrosine residue at position 169 is strictly conserved among mammals, and transgenic mice expressing mouse PrP having the Y169G, S170N, and N174T substitutions resist prion infection. To better understand the structural requirements of specific residues for conversion initiated by mouse prions, we substituted a diverse array of amino acids at position 169 of PrP. We found that the substitution of glycine, leucine, or glutamine at position 169 reduced conversion by ∼ 75%. In contrast, replacing tyrosine 169 with either of the bulky, aromatic residues, phenylalanine or tryptophan, supported efficient prion conversion. We propose a model based on a requirement for tightly interdigitating complementary amino acid side chains within specific domains of adjacent PrP molecules, known as "steric zippers," to explain these results. Collectively, these studies suggest that an aromatic residue at position 169 supports efficient prion conversion.
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Affiliation(s)
- Timothy D Kurt
- Department of Pathology and Medicine, University of California San Diego, La Jolla, California 92093
| | - Lin Jiang
- Department of Energy Institute for Genomics and Proteomics, Howard Hughes Medical Institute, and Molecular Biology Institute, UCLA, Los Angeles, California 90095
| | - Cyrus Bett
- Department of Pathology and Medicine, University of California San Diego, La Jolla, California 92093
| | - David Eisenberg
- Department of Energy Institute for Genomics and Proteomics, Howard Hughes Medical Institute, and Molecular Biology Institute, UCLA, Los Angeles, California 90095
| | - Christina J Sigurdson
- Department of Pathology and Medicine, University of California San Diego, La Jolla, California 92093; Department of Pathology, Immunology, and Microbiology, University of California, Davis, California 95616.
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16
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Molecular dynamics studies on the NMR and X-ray structures of rabbit prion proteins. J Theor Biol 2013; 342:70-82. [PMID: 24184221 DOI: 10.1016/j.jtbi.2013.10.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2013] [Revised: 08/25/2013] [Accepted: 10/09/2013] [Indexed: 12/27/2022]
Abstract
Prion diseases, traditionally referred to as transmissible spongiform encephalopathies (TSEs), are invariably fatal and highly infectious neurodegenerative diseases that affect a wide variety of mammalian species, manifesting as scrapie in sheep and goats, bovine spongiform encephalopathy (BSE or mad-cow disease) in cattle, chronic wasting disease in deer and elk, and Creutzfeldt-Jakob diseases, Gerstmann-Sträussler-Scheinker syndrome, fatal familial insomnia, and kulu in humans, etc. These neurodegenerative diseases are caused by the conversion from a soluble normal cellular prion protein (PrP(C)) into insoluble abnormally folded infectious prions (PrP(Sc)), and the conversion of PrP(C) to PrP(Sc) is believed to involve conformational change from a predominantly α-helical protein to one rich in β-sheet structure. Such a conformational change may be amenable to study by molecular dynamics (MD) techniques. For rabbits, classical studies show that they have a low susceptibility to be infected by PrP(Sc), but recently it was reported that rabbit prions can be generated through saPMCA (serial automated Protein Misfolding Cyclic Amplification) in vitro and the rabbit prion is infectious and transmissible. In this paper, we first do a detailed survey on the research advances of rabbit prion protein (RaPrP) and then we perform MD simulations on the NMR and X-ray molecular structures of rabbit prion protein wild-type and mutants. The survey shows to us that rabbits were not challenged directly in vivo with other known prion strains and the saPMCA result did not pass the test of the known BSE strain of cattle. Thus, we might still look rabbits as a prion resistant species. MD results indicate that the three α-helices of the wild-type are stable under the neutral pH environment (but under low pH environment the three α-helices have been unfolded into β-sheets), and the three α-helices of the mutants (I214V and S173N) are unfolded into rich β-sheet structures under the same pH environment. In addition, we found an interesting result that the salt bridges such as ASP201-ARG155, ASP177-ARG163 contribute greatly to the structural stability of RaPrP.
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17
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Sica RE. Is amyotrophic lateral sclerosis a primary astrocytic disease? Med Hypotheses 2012; 79:819-22. [PMID: 23026704 DOI: 10.1016/j.mehy.2012.08.036] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2012] [Revised: 08/15/2012] [Accepted: 08/23/2012] [Indexed: 12/12/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) is thought to be due to primary involvement of motor neurons. Pathogenic mechanisms underlying its appearance are relatively well known and include inflammation, excitotoxicity, oxidative stress, endoplasmic reticulum stress, protein damage, genetic abnormalities and type of neuronal death. Although these processes have been investigated in detail in the past two decades none of them appear to be the cause of the illness. In addition several possible environmental agents have been investigated but the results, in every case, were conflicting and therefore inconclusive. However, since the motor neurons display the features of apoptosis in this illness, the possibility remains that the motor neurons die because of a hostile environment, one that is unable to sustain their health, rather than being directly targeted themselves. The above considerations lead to an examination of astrocytes, for these cells play a key role in controlling the environment of neurons. It is known that astrocytes are exquisitely plastic, adapting their metabolism and behaviour to the needs of the neurons they contact. Each population of astrocytes is therefore unique and, were one to be adversely affected at the start of a disease process, the consequences would extend to the neurons that it normally chaperoned. The disturbed relationship might involve inappropriate production and secretion of astrocytic neurotransmitters, defective transport of glutamate and impaired trophic and metabolic support of the motor neurons. In order to explain the spread of weakness and pyramidal signs in ALS patients, which is very often from one group of muscles to a neighbouring one, it is postulated that, within the spinal cord, the brainstem and the motor cortex, the disease-causing process is also spreading-in this case, from one group of astrocytes to its neighbours. A misfolded protein, possibly a prion-like protein, would be a candidate for this type of transmission.
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Affiliation(s)
- Roberto E Sica
- Department of Neurology, Buenos Aires University, Argentina.
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18
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Sang JC, Lee CY, Luh FY, Huang YW, Chiang YW, Chen RPY. Slow spontaneous α-to-β structural conversion in a non-denaturing neutral condition reveals the intrinsically disordered property of the disulfide-reduced recombinant mouse prion protein. Prion 2012; 6:489-97. [PMID: 22987112 PMCID: PMC3510854 DOI: 10.4161/pri.22217] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
In prion diseases, the normal prion protein is transformed by an unknown mechanism from a mainly α-helical structure to a β-sheet-rich, disease-related isomer. In this study, we surprisingly found that a slow, spontaneous α-to-coil-to-β transition could be monitored by circular dichroism spectroscopy in one full-length mouse recombinant prion mutant protein, denoted S132C/N181C, in which the endogenous cysteines C179 and C214 were replaced by Ala and S132 and N181 were replaced by Cys, during incubation in a non-denaturing neutral buffer. No denaturant was required to destabilize the native state for the conversion. The product after this structural conversion is toxic β-oligomers with high fluorescence intensity when binding with thioflavin T. Site-directed spin-labeling ESR data suggested that the structural conversion involves the unfolding of helix 2. After examining more protein mutants, it was found that the spontaneous structural conversion is due to the disulfide-deletion (C to A mutations). The recombinant wild-type mouse prion protein could also be transformed into β-oligomers and amyloid fibrils simply by dissolving and incubating the protein in 0.5 mM NaOAc (pH 7) and 1 mM DTT at 25°C with no need of adding any denaturant to destabilize the prion protein. Our findings indicate the important role of disulfide bond reduction on the structural conversion of the recombinant prion protein, and highlight the special “intrinsically disordered” conformational character of the recombinant prion protein.
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Affiliation(s)
- Jason C Sang
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan
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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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20
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Abstract
This chapter focuses on the structural conversion of natural and recombinant prion proteins in vitro. They key event in prion diseases is the conversion of the cellular prion protein (PrP(C)) into its disease causing isoform PrP(Sc). This conversion is represented by a conformational change from an β-helical dominated isoform into the mostly β-sheeted PrP(Sc). Represented is an overview of in vitro conversion systems that result in β-structured recombinant prion proteins including the current achievements in the generation of synthetic mammalian prions as proof of the protein-only hypothesis. In addition to the conversion of recombinant PrP the chapter features a summary of the protein misfolding cyclic amplification (PMCA) technique which has gained enormous popularity in prion research. Given is a general overview about the technique itself and the broad spectrum of utilization as detection method for prions. The spontaneous generation of prions by the protein misfolding amplification (PMCA) are also discussed.
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Browning S, Baker CA, Smith E, Mahal SP, Herva ME, Demczyk CA, Li J, Weissmann C. Abrogation of complex glycosylation by swainsonine results in strain- and cell-specific inhibition of prion replication. J Biol Chem 2011; 286:40962-73. [PMID: 21930694 PMCID: PMC3220511 DOI: 10.1074/jbc.m111.283978] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2011] [Revised: 08/30/2011] [Indexed: 11/06/2022] Open
Abstract
Neuroblastoma-derived N2a-PK1 cells, fibroblastic LD9 cells, and CNS-derived CAD5 cells can be infected efficiently and persistently by various prion strains, as measured by the standard scrapie cell assay. Swainsonine, an inhibitor of Golgi α-mannosidase II that causes abnormal N-glycosylation, strongly inhibits infection of PK1 cells by RML, 79A and 22F, less so by 139A, and not at all by 22L prions, and it does not diminish propagation of any of these strains in LD9 or CAD5 cells. Misglycosylated PrP(C) formed in the presence of swainsonine is a good substrate for conversion to PrP(Sc), and misglycosylated PrP(Sc) is fully able to trigger infection and seed the protein misfolding cyclic amplification reaction. Distinct subclones of PK1 cells mediate swainsonine inhibition to very different degrees, implicating misglycosylation of one or more host proteins in the inhibitory process. The use of swainsonine and other glycosylation inhibitors described herein enhances the ability of the cell panel assay to differentiate between prion strains. Moreover, as shown elsewhere, the susceptibility of prions to inhibition by swainsonine in PK1 cells is a mutable trait.
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Affiliation(s)
- Shawn Browning
- From the Department of Infectology, Scripps Florida, Jupiter, Florida 33458
| | | | - Emery Smith
- From the Department of Infectology, Scripps Florida, Jupiter, Florida 33458
| | - Sukhvir P. Mahal
- From the Department of Infectology, Scripps Florida, Jupiter, Florida 33458
| | - Maria E. Herva
- From the Department of Infectology, Scripps Florida, Jupiter, Florida 33458
| | - Cheryl A. Demczyk
- From the Department of Infectology, Scripps Florida, Jupiter, Florida 33458
| | - Jiali Li
- From the Department of Infectology, Scripps Florida, Jupiter, Florida 33458
| | - Charles Weissmann
- From the Department of Infectology, Scripps Florida, Jupiter, Florida 33458
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