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Teruya K, Oguma A, Iwabuchi S, Nishizawa K, Doh-Ura K. Improvement of anti-prion efficacy with stearoxy conjugation of hydroxypropyl methylcellulose in prion-infected mice. Carbohydr Polym 2024; 337:122163. [PMID: 38710557 DOI: 10.1016/j.carbpol.2024.122163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Revised: 04/11/2024] [Accepted: 04/12/2024] [Indexed: 05/08/2024]
Abstract
Prion diseases are fatal transmissible neurodegenerative disorders. Among known anti-prions, hydroxypropyl methylcellulose compounds (HPMCs) are unique in their chemical structure and action. They have several excellent anti-prion properties but the effectiveness depends on the prion-infected mouse model. In the present study, we investigated the effects of stearoxy-modified HPMCs on prion-infected cells and mice. Stearoxy modification improved the anti-prion efficacy of HPMCs in prion-infected cells and significantly prolonged the incubation period in a lower HPMC-responding mouse model. However, stearoxy modification showed no improvement over nonmodified HPMCs in an HPMC-responding mouse model. These results offer a new line of inquiry for use with prion-infected mice that do not respond well to HPMCs.
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Affiliation(s)
- Kenta Teruya
- Department of Neurochemistry, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan.
| | - Ayumi Oguma
- Department of Neurochemistry, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan.
| | - Sara Iwabuchi
- Department of Neurochemistry, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan.
| | - Keiko Nishizawa
- Department of Neurochemistry, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan.
| | - Katsumi Doh-Ura
- Department of Neurochemistry, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan; Faculty of Medical Science & Welfare, Tohoku Bunka Gakuen University, Sendai, Miyagi, Japan.
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2
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Wang SS, Meng ZL, Zhang YW, Yan YS, Li LB. Prion protein E219K polymorphism: from the discovery of the KANNO blood group to interventions for human prion disease. Front Neurol 2024; 15:1392984. [PMID: 39050130 PMCID: PMC11266091 DOI: 10.3389/fneur.2024.1392984] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2024] [Accepted: 06/26/2024] [Indexed: 07/27/2024] Open
Abstract
KANNO is a new human blood group that was recently discovered. The KANNO antigen shares the PRNP gene with the prion protein and the prion protein E219K polymorphism determines the presence or absence of the KANNO antigen and the development of anti-KANNO alloantibodies. These alloantibodies specifically react with prion proteins, which serve as substrates for conversion into pathological isoforms in some prion diseases and may serve as effective targets for resisting prion infection. These findings establish a potential link between the KANNO blood group and human prion disease via the prion protein E219K polymorphism. We reviewed the interesting correlation between the human PRNP gene's E219K polymorphism and the prion proteins it expresses, as well as human red blood cell antigens. Based on the immune serological principles of human blood cells, the prion protein E219K polymorphism may serve as a foundation for earlier molecular diagnosis and future drug development for prion diseases.
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Affiliation(s)
- Si-Si Wang
- Department of Translational Medicine, The First Hospital of Jilin University, Changchun, China
| | - Zhao-Li Meng
- Department of Translational Medicine, The First Hospital of Jilin University, Changchun, China
| | - Yi-Wen Zhang
- Department of Translational Medicine, The First Hospital of Jilin University, Changchun, China
| | - Yi-Shuang Yan
- Department of Translational Medicine, The First Hospital of Jilin University, Changchun, China
| | - Ling-Bo Li
- Aikang MedTech Co., Ltd., Shenzhen, China
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3
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Shoup D, Priola SA. Full-length prion protein incorporated into prion aggregates is a marker for prion strain-specific destabilization of aggregate structure following cellular uptake. J Biochem 2023; 174:165-181. [PMID: 37099550 PMCID: PMC10506170 DOI: 10.1093/jb/mvad032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Revised: 03/30/2023] [Accepted: 04/09/2023] [Indexed: 04/27/2023] Open
Abstract
Accumulation of insoluble aggregates of infectious, partially protease-resistant prion protein (PrPD) generated via the misfolding of protease sensitive prion protein (PrPC) into the same infectious conformer, is a hallmark of prion diseases. Aggregated PrPD is taken up and degraded by cells, a process likely involving changes in aggregate structure that can be monitored by accessibility of the N-terminus of full-length PrPD to cellular proteases. We therefore tracked the protease sensitivity of full-length PrPD before and after cellular uptake for two murine prion strains, 22L and 87V. For both strains, PrPD aggregates were less stable following cellular uptake with increased accessibility of the N-terminus to cellular proteases across most aggregate sizes. However, a limited size range of aggregates was able to better protect the N-termini of full-length PrPD, with the N-terminus of 22L-derived PrPD more protected than that of 87V. Interestingly, changes in aggregate structure were associated with minimal changes to the protease-resistant core of PrPD. Our data show that cells destabilize the aggregate quaternary structure protecting PrPD from proteases in a strain-dependent manner, with structural changes exposing protease sensitive PrPD having little effect on the protease-resistant core, and thus conformation, of aggregated PrPD.
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Affiliation(s)
- Daniel Shoup
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy & Infectious Diseases, National Institutes of Health, 903 S. 4th Str, Hamilton, MT 59840 USA
| | - Suzette A Priola
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy & Infectious Diseases, National Institutes of Health, 903 S. 4th Str, Hamilton, MT 59840 USA
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Kobayashi A, Hirata T, Shimazaki T, Munesue Y, Aoshima K, Kimura T, Nio-Kobayashi J, Hasebe R, Takeuchi A, Matsuura Y, Kusumi S, Koga D, Iwasaki Y, Kinoshita T, Mohri S, Kitamoto T. A point mutation in GPI-attachment signal peptide accelerates the development of prion disease. Acta Neuropathol 2023; 145:637-650. [PMID: 36879070 DOI: 10.1007/s00401-023-02553-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Revised: 02/26/2023] [Accepted: 02/27/2023] [Indexed: 03/08/2023]
Abstract
A missense variant from methionine to arginine at codon 232 (M232R) of the prion protein gene accounts for ~ 15% of Japanese patients with genetic prion diseases. However, pathogenic roles of the M232R substitution for the induction of prion disease have remained elusive because family history is usually absent in patients with M232R. In addition, the clinicopathologic phenotypes of patients with M232R are indistinguishable from those of sporadic Creutzfeldt-Jakob disease patients. Furthermore, the M232R substitution is located in the glycosylphosphatidylinositol (GPI)-attachment signal peptide that is cleaved off during the maturation of prion proteins. Therefore, there has been an argument that the M232R substitution might be an uncommon polymorphism rather than a pathogenic mutation. To unveil the role of the M232R substitution in the GPI-attachment signal peptide of prion protein in the pathogenesis of prion disease, here we generated a mouse model expressing human prion proteins with M232R and investigated the susceptibility to prion disease. The M232R substitution accelerates the development of prion disease in a prion strain-dependent manner, without affecting prion strain-specific histopathologic and biochemical features. The M232R substitution did not alter the attachment of GPI nor GPI-attachment site. Instead, the substitution altered endoplasmic reticulum translocation pathway of prion proteins by reducing the hydrophobicity of the GPI-attachment signal peptide, resulting in the reduction of N-linked glycosylation and GPI glycosylation of prion proteins. To the best of our knowledge, this is the first time to show a direct relationship between a point mutation in the GPI-attachment signal peptide and the development of disease.
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Affiliation(s)
- Atsushi Kobayashi
- Laboratory of Comparative Pathology, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido, 060-0818, Japan.
- Department of Biomedical Models, Graduate School of Biomedical Sciences, Nagasaki University, 1-12-4, Sakamoto, Nagasaki, 852-8523, Japan.
| | - Tetsuya Hirata
- Institute for Glyco-core Research (iGCORE), Gifu University, 501-1193, Gifu, Japan
| | - Taishi Shimazaki
- Laboratory of Comparative Pathology, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido, 060-0818, Japan
| | - Yoshiko Munesue
- Laboratory of Comparative Pathology, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido, 060-0818, Japan
| | - Keisuke Aoshima
- Laboratory of Comparative Pathology, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido, 060-0818, Japan
| | - Takashi Kimura
- Laboratory of Comparative Pathology, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido, 060-0818, Japan
| | - Junko Nio-Kobayashi
- Laboratory of Histology and Cytology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, 060-8638, Japan
| | - Rie Hasebe
- Biomedical Animal Research Laboratory, Institute for Genetic Medicine, Hokkaido University, Sapporo, Hokkaido, 060-0615, Japan
| | - Atsuko Takeuchi
- Department of Neurological Science, Tohoku University Graduate School of Medicine, Sendai, Miyagi, 980-8575, Japan
| | - Yuichi Matsuura
- National Institute of Animal Health, National Agriculture and Food Research Organization, Tsukuba, Ibaraki, 305-0856, Japan
| | - Satoshi Kusumi
- Division of Morphological Sciences, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, 890-8544, Japan
| | - Daisuke Koga
- Department of Microscopic Anatomy and Cell Biology, Asahikawa Medical University, Asahikawa, Hokkaido, 078-8510, Japan
| | - Yasushi Iwasaki
- Department of Neuropathology, Institute for Medical Science of Aging, Aichi Medical University, Nagakute, Aichi, 480-1195, Japan
| | - Taroh Kinoshita
- Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, 565-0871, Japan
- WPI Immunology Frontier Research Center, Osaka University, Suita, Osaka, 565-0871, Japan
- Center for Infectious Disease Education and Research, Osaka University, Suita, Osaka, 565-0871, Japan
| | - Shirou Mohri
- Department of Neurological Science, Tohoku University Graduate School of Medicine, Sendai, Miyagi, 980-8575, Japan
- Research Center for Biomedical Models and Animal Welfare, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, 852-8523, Japan
| | - Tetsuyuki Kitamoto
- Department of Neurological Science, Tohoku University Graduate School of Medicine, Sendai, Miyagi, 980-8575, Japan
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Silva CJ, Erickson-Beltran ML. General Method of Quantifying the Extent of Methionine Oxidation in the Prion Protein. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2023; 34:255-263. [PMID: 36608322 DOI: 10.1021/jasms.2c00280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
The normal cellular prion protein (PrPC) and its infectious conformer, PrPSc, possess a disproportionately greater amount of methionines than would be expected for a typical mammalian protein. The thioether of methionine can be readily oxidized to the corresponding sulfoxide, which means that oxidation of methionine can be used to map the surface of the conformation of PrPC or PrPSc, as covalent changes are retained after denaturation. We identified a set of peptides (TNMK, MLGSAMSR, LLGSAMSR, PMIHFGNDWEDR, ENMNR, ENMYR, IMER, MMER, MIER, VVEQMCVTQYQK, and VVEQMCITQYQR) that contains every methionine in sheep, cervid, mouse, and bank vole PrP. Each is the product of a tryptic digestion and is suitable for a multiple reaction monitoring (MRM) based analysis. The peptides chromatograph well. The oxidized and unoxidized peptides containing one methionine readily separate. The unoxidized, two singly oxidized, and doubly oxidized forms of the MLGSAMSR and MMER peptides are also readily distinguishable. This approach can be used to determine the surface exposure of each methionine by measuring its oxidation after reaction with added hydrogen peroxide.
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Affiliation(s)
- Christopher J Silva
- Produce Safety and Microbiology Research Unit, Western Regional Research Center, United States Department of Agriculture, Agricultural Research Service, 800 Buchanan Street, Albany, California 94710, United States
| | - Melissa L Erickson-Beltran
- Produce Safety and Microbiology Research Unit, Western Regional Research Center, United States Department of Agriculture, Agricultural Research Service, 800 Buchanan Street, Albany, California 94710, United States
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6
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Hoyt F, Alam P, Artikis E, Schwartz CL, Hughson AG, Race B, Baune C, Raymond GJ, Baron GS, Kraus A, Caughey B. Cryo-EM of prion strains from the same genotype of host identifies conformational determinants. PLoS Pathog 2022; 18:e1010947. [PMID: 36342968 PMCID: PMC9671466 DOI: 10.1371/journal.ppat.1010947] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2022] [Revised: 11/17/2022] [Accepted: 10/24/2022] [Indexed: 11/09/2022] Open
Abstract
Prion strains in a given type of mammalian host are distinguished by differences in clinical presentation, neuropathological lesions, survival time, and characteristics of the infecting prion protein (PrP) assemblies. Near-atomic structures of prions from two host species with different PrP sequences have been determined but comparisons of distinct prion strains of the same amino acid sequence are needed to identify purely conformational determinants of prion strain characteristics. Here we report a 3.2 Å resolution cryogenic electron microscopy-based structure of the 22L prion strain purified from the brains of mice engineered to express only PrP lacking glycophosphatidylinositol anchors [anchorless (a) 22L]. Comparison of this near-atomic structure to our recently determined structure of the aRML strain propagated in the same inbred mouse reveals that these two mouse prion strains have distinct conformational templates for growth via incorporation of PrP molecules of the same sequence. Both a22L and aRML are assembled as stacks of PrP molecules forming parallel in-register intermolecular β-sheets and intervening loops, with single monomers spanning the ordered fibril core. Each monomer shares an N-terminal steric zipper, three major arches, and an overall V-shape, but the details of these and other conformational features differ markedly. Thus, variations in shared conformational motifs within a parallel in-register β-stack fibril architecture provide a structural basis for prion strain differentiation within a single host genotype. Prions are protein-based pathogens that can spread within and between hosts without carrying a pathogen-specific nucleic acid genome. Given this protein-based propagation mechanism, a long-standing mystery in the prion disease field has been the molecular basis of distinct, faithfully propagating strains in a single type of mammalian host. Here we provide a direct, high-resolution cryo-EM-based comparison of the structures of two highly infectious prion strains isolated from the brains of mice of a single genotype. We show in detail how these two prion strains are protein filaments of mouse PrP molecules that display distinct conformational templates for growth on their tips. Our results identify purely conformational, rather than sequence-based, underpinnings of infectious and deadly prion strains.
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Affiliation(s)
- Forrest Hoyt
- Research Technologies Branch, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Parvez Alam
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Efrosini Artikis
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Cindi L. Schwartz
- Research Technologies Branch, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Andrew G. Hughson
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Brent Race
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Chase Baune
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Gregory J. Raymond
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Gerald S. Baron
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Allison Kraus
- Department of Pathology, Case Western Reserve University School of Medicine, Cleveland, Ohio, United States of America
- Cleveland Center for Membrane and Structural Biology, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Byron Caughey
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
- * E-mail:
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7
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Cryo-EM structure of anchorless RML prion reveals variations in shared motifs between distinct strains. Nat Commun 2022; 13:4005. [PMID: 35831291 PMCID: PMC9279418 DOI: 10.1038/s41467-022-30458-6] [Citation(s) in RCA: 36] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Accepted: 04/27/2022] [Indexed: 11/08/2022] Open
Abstract
Little is known about the structural basis of prion strains. Here we provide a high (3.0 Å) resolution cryo-electron microscopy-based structure of infectious brain-derived fibrils of the mouse anchorless RML scrapie strain which, like the recently determined hamster 263K strain, has a parallel in-register β-sheet-based core. Several structural motifs are shared between these ex vivo prion strains, including an amino-proximal steric zipper and three β-arches. However, detailed comparisons reveal variations in these shared structural topologies and other features. Unlike 263K and wildtype RML prions, the anchorless RML prions lack glycophosphatidylinositol anchors and are severely deficient in N-linked glycans. Nonetheless, the similarity of our anchorless RML structure to one reported for wildtype RML prion fibrils in an accompanying paper indicates that these post-translational modifications do not substantially alter the amyloid core conformation. This work demonstrates both common and divergent structural features of prion strains at the near-atomic level.
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8
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Artikis E, Kraus A, Caughey B. Structural biology of ex vivo mammalian prions. J Biol Chem 2022; 298:102181. [PMID: 35752366 PMCID: PMC9293645 DOI: 10.1016/j.jbc.2022.102181] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 06/16/2022] [Accepted: 06/19/2022] [Indexed: 01/13/2023] Open
Abstract
The structures of prion protein (PrP)–based mammalian prions have long been elusive. However, cryo-EM has begun to reveal the near-atomic resolution structures of fully infectious ex vivo mammalian prion fibrils as well as relatively innocuous synthetic PrP amyloids. Comparisons of these various types of PrP fibrils are now providing initial clues to structural features that correlate with pathogenicity. As first indicated by electron paramagnetic resonance and solid-state NMR studies of synthetic amyloids, all sufficiently resolved PrP fibrils of any sort (n > 10) have parallel in-register intermolecular β-stack architectures. Cryo-EM has shown that infectious brain-derived prion fibrils of the rodent-adapted 263K and RML scrapie strains have much larger ordered cores than the synthetic fibrils. These bona fide prion strains share major structural motifs, but the conformational details and the overall shape of the fibril cross sections differ markedly. Such motif variations, as well as differences in sequence within the ordered polypeptide cores, likely contribute to strain-dependent templating. When present, N-linked glycans and glycophosphatidylinositol (GPI) anchors project outward from the fibril surface. For the mouse RML strain, these posttranslational modifications have little effect on the core structure. In the GPI-anchored prion structures, a linear array of GPI anchors along the twisting fibril axis appears likely to bind membranes in vivo, and as such, may account for pathognomonic membrane distortions seen in prion diseases. In this review, we focus on these infectious prion structures and their implications regarding prion replication mechanisms, strains, transmission barriers, and molecular pathogenesis.
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Affiliation(s)
- Efrosini Artikis
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT 59840 USA
| | - Allison Kraus
- Department of Pathology, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA.
| | - Byron Caughey
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT 59840 USA.
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9
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Silva CJ. Chronic Wasting Disease (CWD) in Cervids and the Consequences of a Mutable Protein Conformation. ACS OMEGA 2022; 7:12474-12492. [PMID: 35465121 PMCID: PMC9022204 DOI: 10.1021/acsomega.2c00155] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2022] [Accepted: 03/18/2022] [Indexed: 05/15/2023]
Abstract
Chronic wasting disease (CWD) is a prion disease of cervids (deer, elk, moose, etc.). It spreads readily from CWD-contaminated environments and among wild cervids. As of 2022, North American CWD has been found in 29 states, four Canadian provinces and South Korea. The Scandinavian form of CWD originated independently. Prions propagate their pathology by inducing a natively expressed prion protein (PrPC) to adopt the prion conformation (PrPSc). PrPC and PrPSc differ solely in their conformation. Like other prion diseases, transmissible CWD prions can arise spontaneously. The CWD prions can respond to selection pressures resulting in the emergence of new strain phenotypes. Annually, 11.5 million Americans hunt and harvest nearly 6 million deer, indicating that CWD is a potential threat to an important American food source. No tested CWD strain has been shown to be zoonotic. However, this may not be true for emerging strains. Should a zoonotic CWD strain emerge, it could adversely impact the hunting economy and game meat consumers.
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Affiliation(s)
- Christopher J. Silva
- Produce Safety & Microbiology
Research Unit, Western Regional Research Center, Agricultural Research
Service, United States Department of Agriculture, Albany, California 94710, United States of America
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10
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Activities of curcumin-related compounds in two cell lines persistently infected with different prion strains. Biochim Biophys Acta Gen Subj 2022; 1866:130094. [DOI: 10.1016/j.bbagen.2022.130094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 01/11/2022] [Accepted: 01/14/2022] [Indexed: 11/18/2022]
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11
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Silva CJ, Erickson-Beltran M. Detecting Differences in Prion Protein Conformation by Quantifying Methionine Oxidation. ACS OMEGA 2022; 7:2649-2660. [PMID: 35097263 PMCID: PMC8793083 DOI: 10.1021/acsomega.1c04989] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Accepted: 12/24/2021] [Indexed: 06/14/2023]
Abstract
A prion's pathogenic character is enciphered in its conformation, which also defines the chemical environments of its amino acids. Differences in chemical environments influence the reactivity of amino acid side chains, in a conformation-dependent manner. Chemical oxidation of susceptible methionines would identify those methionines on the surface of a prion, which would reveal conformation-dependent information. We identified a set of methionine-containing peptides derived from the tryptic, chymotryptic, or tryptic/chymotryptic digestion of recombinant prion protein and the Sc237 strain of hamster-adapted scrapie. We developed a multiple reaction monitoring-based method of quantifying the extent of the methionine oxidation in those peptides. This approach can be used to define a prion's conformation and to distinguish among prion strains, which is an important component of food safety.
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12
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High-resolution structure and strain comparison of infectious mammalian prions. Mol Cell 2021; 81:4540-4551.e6. [PMID: 34433091 DOI: 10.1016/j.molcel.2021.08.011] [Citation(s) in RCA: 113] [Impact Index Per Article: 37.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 05/29/2021] [Accepted: 08/09/2021] [Indexed: 11/23/2022]
Abstract
Within the extensive range of self-propagating pathologic protein aggregates of mammals, prions are the most clearly infectious (e.g., ∼109 lethal doses per milligram). The structures of such lethal assemblies of PrP molecules have been poorly understood. Here we report a near-atomic core structure of a brain-derived, fully infectious prion (263K strain). Cryo-electron microscopy showed amyloid fibrils assembled with parallel in-register intermolecular β sheets. Each monomer provides one rung of the ordered fibril core, with N-linked glycans and glycolipid anchors projecting outward. Thus, single monomers form the templating surface for incoming monomers at fibril ends, where prion growth occurs. Comparison to another prion strain (aRML) revealed major differences in fibril morphology but, like 263K, an asymmetric fibril cross-section without paired protofilaments. These findings provide structural insights into prion propagation, strains, species barriers, and membrane pathogenesis. This structure also helps frame considerations of factors influencing the relative transmissibility of other pathologic amyloids.
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13
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Short and sweet: How glycans impact prion conversion, cofactor interactions, and cross-species transmission. PLoS Pathog 2021; 17:e1009123. [PMID: 33444414 PMCID: PMC7808606 DOI: 10.1371/journal.ppat.1009123] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
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14
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Sevillano AM, Aguilar-Calvo P, Kurt TD, Lawrence JA, Soldau K, Nam TH, Schumann T, Pizzo DP, Nyström S, Choudhury B, Altmeppen H, Esko JD, Glatzel M, Nilsson KPR, Sigurdson CJ. Prion protein glycans reduce intracerebral fibril formation and spongiosis in prion disease. J Clin Invest 2020; 130:1350-1362. [PMID: 31985492 DOI: 10.1172/jci131564] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Accepted: 11/13/2019] [Indexed: 12/12/2022] Open
Abstract
Posttranslational modifications (PTMs) are common among proteins that aggregate in neurodegenerative disease, yet how PTMs impact the aggregate conformation and disease progression remains unclear. By engineering knockin mice expressing prion protein (PrP) lacking 2 N-linked glycans (Prnp180Q/196Q), we provide evidence that glycans reduce spongiform degeneration and hinder plaque formation in prion disease. Prnp180Q/196Q mice challenged with 2 subfibrillar, non-plaque-forming prion strains instead developed plaques highly enriched in ADAM10-cleaved PrP and heparan sulfate (HS). Intriguingly, a third strain composed of intact, glycophosphatidylinositol-anchored (GPI-anchored) PrP was relatively unchanged, forming diffuse, HS-deficient deposits in both the Prnp180Q/196Q and WT mice, underscoring the pivotal role of the GPI-anchor in driving the aggregate conformation and disease phenotype. Finally, knockin mice expressing triglycosylated PrP (Prnp187N) challenged with a plaque-forming prion strain showed a phenotype reversal, with a striking disease acceleration and switch from plaques to predominantly diffuse, subfibrillar deposits. Our findings suggest that the dominance of subfibrillar aggregates in prion disease is due to the replication of GPI-anchored prions, with fibrillar plaques forming from poorly glycosylated, GPI-anchorless prions that interact with extracellular HS. These studies provide insight into how PTMs impact PrP interactions with polyanionic cofactors, and highlight PTMs as a major force driving the prion disease phenotype.
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Affiliation(s)
| | | | - Timothy D Kurt
- Department of Pathology, UCSD, La Jolla, California, USA
| | | | - Katrin Soldau
- Department of Pathology, UCSD, La Jolla, California, USA
| | - Thu H Nam
- Department of Pathology, UCSD, La Jolla, California, USA
| | | | - Donald P Pizzo
- Department of Pathology, UCSD, La Jolla, California, USA
| | - Sofie Nyström
- Department of Physics, Chemistry, and Biology, Linköping University, Linköping, Sweden
| | - Biswa Choudhury
- Department of Cellular and Molecular Medicine, UCSD, La Jolla, California, USA
| | - Hermann Altmeppen
- Institute of Neuropathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Jeffrey D Esko
- Department of Cellular and Molecular Medicine, UCSD, La Jolla, California, USA
| | - Markus Glatzel
- Institute of Neuropathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - K Peter R Nilsson
- Department of Physics, Chemistry, and Biology, Linköping University, Linköping, Sweden
| | - Christina J Sigurdson
- Department of Pathology, UCSD, La Jolla, California, USA.,Department of Medicine, UCSD, La Jolla, California, USA.,Department of Pathology, Immunology, and Microbiology, UCD, Davis, California, USA
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15
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Callender JA, Sevillano AM, Soldau K, Kurt TD, Schumann T, Pizzo DP, Altmeppen H, Glatzel M, Esko JD, Sigurdson CJ. Prion protein post-translational modifications modulate heparan sulfate binding and limit aggregate size in prion disease. Neurobiol Dis 2020; 142:104955. [PMID: 32454127 DOI: 10.1016/j.nbd.2020.104955] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Revised: 05/09/2020] [Accepted: 05/21/2020] [Indexed: 01/05/2023] Open
Abstract
Many aggregation-prone proteins linked to neurodegenerative disease are post-translationally modified during their biogenesis. In vivo pathogenesis studies have suggested that the presence of post-translational modifications can shift the aggregate assembly pathway and profoundly alter the disease phenotype. In prion disease, the N-linked glycans and GPI-anchor on the prion protein (PrP) impair fibril assembly. However, the relevance of the two glycans to aggregate structure and disease progression remains unclear. Here we show that prion-infected knockin mice expressing an additional PrP glycan (tri-glycosylated PrP) develop new plaque-like deposits on neuronal cell membranes, along the subarachnoid space, and periventricularly, suggestive of high prion mobility and transit through the interstitial fluid. These plaque-like deposits were largely non-congophilic and composed of full length, uncleaved PrP, indicating retention of the glycophosphatidylinositol (GPI) anchor. Prion aggregates sedimented in low density fractions following ultracentrifugation, consistent with oligomers, and bound low levels of heparan sulfate (HS) similar to other predominantly GPI-anchored prions. Collectively, these results suggest that highly glycosylated PrP primarily converts as a GPI-anchored glycoform, with low involvement of HS co-factors, limiting PrP assembly mainly to oligomers. Since PrPC is highly glycosylated, these findings may explain the high frequency of diffuse, synaptic, and plaque-like deposits in the brain as well as the rapid conversion commonly observed in human and animal prion disease.
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Affiliation(s)
| | | | - Katrin Soldau
- Departments of Pathology, UC San Diego, La Jolla, CA 92093, USA
| | - Timothy D Kurt
- Departments of Pathology, UC San Diego, La Jolla, CA 92093, USA
| | - Taylor Schumann
- Departments of Pathology, UC San Diego, La Jolla, CA 92093, USA
| | - Donald P Pizzo
- Departments of Pathology, UC San Diego, La Jolla, CA 92093, USA
| | - Hermann Altmeppen
- Institute of Neuropathology, University Medical Center Hamburg-Eppendorf (UKE), Hamburg, 20251, Germany
| | - Markus Glatzel
- Institute of Neuropathology, University Medical Center Hamburg-Eppendorf (UKE), Hamburg, 20251, Germany
| | - Jeffrey D Esko
- Department of Cellular and Molecular Medicine, UC San Diego, La Jolla, CA 92093, USA
| | - Christina J Sigurdson
- Department of Pathology, Microbiology, and Immunology, UC Davis, Davis, CA 95616, USA; Departments of Medicine, UC San Diego, La Jolla, CA 92093, USA.
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16
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Israeli R, Kolusheva S, Hadad U, Jelinek R. Imaging Flow Cytometry Illuminates New Dimensions of Amyloid Peptide-Membrane Interactions. Biophys J 2020; 118:1270-1278. [PMID: 32053776 PMCID: PMC7091230 DOI: 10.1016/j.bpj.2020.01.018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 01/06/2020] [Accepted: 01/15/2020] [Indexed: 12/19/2022] Open
Abstract
Membrane interactions of amyloidogenic proteins constitute central determinants both in protein aggregation as well as in amyloid cytotoxicity. Most reported studies of amyloid peptide-membrane interactions have employed model membrane systems combined with application of spectroscopy methods or microscopy analysis of individual binding events. Here, we applied for the first time, to our knowledge, imaging flow cytometry for investigating interactions of representative amyloidogenic peptides, namely, the 106-126 fragment of prion protein (PrP(106-126)) and the human islet amyloid polypeptide (hIAPP), with giant lipid vesicles. Imaging flow cytometry was also applied to examine the inhibition of PrP(106-126)-membrane interactions by epigallocatechin gallate, a known modulator of amyloid peptide aggregation. We show that imaging flow cytometry provided comprehensive population-based statistical information upon morphology changes of the vesicles induced by PrP(106-126) and hIAPP. Specifically, the experiments reveal that both PrP(106-126) and hIAPP induced dramatic transformations of the vesicles, specifically disruption of the spherical shapes, reduction of vesicle circularity, lobe formation, and modulation of vesicle compactness. Interesting differences, however, were apparent between the impact of the two peptides upon the model membranes. The morphology analysis also showed that epigallocatechin gallate ameliorated vesicle disruption by PrP(106-126). Overall, this study demonstrates that imaging flow cytometry provides powerful means for disclosing population-based morphological membrane transformations induced by amyloidogenic peptides and their inhibition by aggregation modulators.
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Affiliation(s)
- Reut Israeli
- Department of Chemistry, Ben-Gurion University of the Negev, Beersheba, Israel
| | - Sofiya Kolusheva
- Department of Chemistry, Ben-Gurion University of the Negev, Beersheba, Israel; Ilse Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, Beersheba, Israel
| | - Uzi Hadad
- Department of Chemistry, Ben-Gurion University of the Negev, Beersheba, Israel; Ilse Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, Beersheba, Israel
| | - Raz Jelinek
- Department of Chemistry, Ben-Gurion University of the Negev, Beersheba, Israel; Ilse Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, Beersheba, Israel.
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17
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Saijo E, Metrick MA, Koga S, Parchi P, Litvan I, Spina S, Boxer A, Rojas JC, Galasko D, Kraus A, Rossi M, Newell K, Zanusso G, Grinberg LT, Seeley WW, Ghetti B, Dickson DW, Caughey B. 4-Repeat tau seeds and templating subtypes as brain and CSF biomarkers of frontotemporal lobar degeneration. Acta Neuropathol 2020; 139:63-77. [PMID: 31616982 PMCID: PMC7192393 DOI: 10.1007/s00401-019-02080-2] [Citation(s) in RCA: 88] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Revised: 09/08/2019] [Accepted: 09/26/2019] [Indexed: 10/25/2022]
Abstract
To address the need for more meaningful biomarkers of tauopathies, we have developed an ultrasensitive tau seed amplification assay (4R RT-QuIC) for the 4-repeat (4R) tau aggregates of progressive supranuclear palsy (PSP), corticobasal degeneration (CBD), and other diseases with 4R tauopathy. The assay detected seeds in 106-109-fold dilutions of 4R tauopathy brain tissue but was orders of magnitude less responsive to brain with other types of tauopathy, such as from Alzheimer's disease cases. The analytical sensitivity for synthetic 4R tau fibrils was ~ 50 fM or 2 fg/sample. A novel dimension of this tau RT-QuIC testing was the identification of three disease-associated classes of 4R tau seeds; these classes were revealed by conformational variations in the in vitro amplified tau fibrils as detected by thioflavin T fluorescence amplitudes and FTIR spectroscopy. Tau seeds were detected in postmortem cerebrospinal fluid (CSF) from all neuropathologically confirmed PSP and CBD cases but not in controls. CSF from living subjects had weaker seeding activities; however, mean assay responses for cases clinically diagnosed as PSP and CBD/corticobasal syndrome were significantly higher than those from control cases. Altogether, 4R RT-QuIC provides a practical cell-free method of detecting and subtyping pathologic 4R tau aggregates as biomarkers.
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Affiliation(s)
- Eri Saijo
- LPVD, Rocky Mountain Laboratories, NIAID, NIH, Hamilton, MT, USA
| | | | - Shunsuke Koga
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
| | - Piero Parchi
- IRCCS Istituto delle Scienze Neurologiche di Bologna, 40139, Bologna, Italy
- Department of Experimental Diagnostic and Specialty Medicine (DIMES), University of Bologna, 40138, Bologna, Italy
| | - Irene Litvan
- Department of Neurosciences, Parkinson and Other Movement Disorders Center, University of California, San Diego, CA, USA
| | - Salvatore Spina
- Memory and Aging Center, Department of Neurology, University of California, San Francisco, CA, USA
| | - Adam Boxer
- Memory and Aging Center, Department of Neurology, University of California, San Francisco, CA, USA
| | - Julio C Rojas
- Memory and Aging Center, Department of Neurology, University of California, San Francisco, CA, USA
| | - Douglas Galasko
- Department of Neurosciences, University of California, San Diego, CA, USA
| | - Allison Kraus
- LPVD, Rocky Mountain Laboratories, NIAID, NIH, Hamilton, MT, USA
| | - Marcello Rossi
- IRCCS Istituto delle Scienze Neurologiche di Bologna, 40139, Bologna, Italy
| | - Kathy Newell
- Indiana University School of Medicine, Indianapolis, IN, USA
| | | | - Lea T Grinberg
- Memory and Aging Center, Department of Neurology, University of California, San Francisco, CA, USA
- Department of Pathology, LIM-22, University of Sao Paulo, Sao Paulo, Brazil
| | - William W Seeley
- Memory and Aging Center, Department of Neurology, University of California, San Francisco, CA, USA
| | | | | | - Byron Caughey
- LPVD, Rocky Mountain Laboratories, NIAID, NIH, Hamilton, MT, USA.
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18
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Hackl S, Becker CFW. Prion protein-Semisynthetic prion protein (PrP) variants with posttranslational modifications. J Pept Sci 2019; 25:e3216. [PMID: 31713950 PMCID: PMC6899880 DOI: 10.1002/psc.3216] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 08/23/2019] [Accepted: 08/23/2019] [Indexed: 12/16/2022]
Abstract
Deciphering the pathophysiologic events in prion diseases is challenging, and the role of posttranslational modifications (PTMs) such as glypidation and glycosylation remains elusive due to the lack of homogeneous protein preparations. So far, experimental studies have been limited in directly analyzing the earliest events of the conformational change of cellular prion protein (PrPC ) into scrapie prion protein (PrPSc ) that further propagates PrPC misfolding and aggregation at the cellular membrane, the initial site of prion infection, and PrP misfolding, by a lack of suitably modified PrP variants. PTMs of PrP, especially attachment of the glycosylphosphatidylinositol (GPI) anchor, have been shown to be crucially involved in the PrPSc formation. To this end, semisynthesis offers a unique possibility to understand PrP behavior invitro and invivo as it provides access to defined site-selectively modified PrP variants. This approach relies on the production and chemoselective linkage of peptide segments, amenable to chemical modifications, with recombinantly produced protein segments. In this article, advances in understanding PrP conversion using semisynthesis as a tool to obtain homogeneous posttranslationally modified PrP will be discussed.
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Affiliation(s)
- Stefanie Hackl
- University of Vienna, Faculty of Chemistry, Institute of Biological Chemistry, Vienna, Austria
| | - Christian F W Becker
- University of Vienna, Faculty of Chemistry, Institute of Biological Chemistry, Vienna, Austria
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19
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Araman C, 't Hart BA. Neurodegeneration meets immunology - A chemical biology perspective. Bioorg Med Chem 2019; 27:1911-1924. [PMID: 30910473 DOI: 10.1016/j.bmc.2019.03.038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 03/14/2019] [Accepted: 03/19/2019] [Indexed: 11/16/2022]
Affiliation(s)
- C Araman
- Leiden Institute of Chemistry and the Institute for Chemical Immunology, Leiden University, Leiden, The Netherlands.
| | - B A 't Hart
- University of Groningen, Department of Biomedical Sciences of Cells and Systems, University Medical Centre, Groningen, The Netherlands; Department Anatomy and Neuroscience, Free University Medical Center (VUmc), Amsterdam, The Netherlands.
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20
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Burke CM, Walsh DJ, Steele AD, Agrimi U, Di Bari MA, Watts JC, Supattapone S. Full restoration of specific infectivity and strain properties from pure mammalian prion protein. PLoS Pathog 2019; 15:e1007662. [PMID: 30908557 PMCID: PMC6448948 DOI: 10.1371/journal.ppat.1007662] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 04/04/2019] [Accepted: 02/27/2019] [Indexed: 12/26/2022] Open
Abstract
The protein-only hypothesis predicts that infectious mammalian prions are composed solely of PrPSc, a misfolded conformer of the normal prion protein, PrPC. However, protein-only PrPSc preparations lack significant levels of prion infectivity, leading to the alternative hypothesis that cofactor molecules are required to form infectious prions. Here, we show that prions with parental strain properties and full specific infectivity can be restored from protein-only PrPSc in vitro. The restoration reaction is rapid, potent, and requires bank vole PrPC substrate, post-translational modifications, and cofactor molecules. To our knowledge, this represents the first report in which the essential properties of an infectious mammalian prion have been restored from pure PrP without adaptation. These findings provide evidence for a unified hypothesis of prion infectivity in which the global structure of protein-only PrPSc accurately stores latent infectious and strain information, but cofactor molecules control a reversible switch that unmasks biological infectivity.
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Affiliation(s)
- Cassandra M. Burke
- Departments of Biochemistry and Cell Biology at Darthmouth, Hanover, New Hampshire, United States of America
| | - Daniel J. Walsh
- Departments of Biochemistry and Cell Biology at Darthmouth, Hanover, New Hampshire, United States of America
| | - Alexander D. Steele
- Departments of Biochemistry and Cell Biology at Darthmouth, Hanover, New Hampshire, United States of America
| | - Umberto Agrimi
- Department of Veterinary Public Health and Food Safety, Istituto Superiore di Sanità, Rome, Italy
| | - Michele Angelo Di Bari
- Department of Veterinary Public Health and Food Safety, Istituto Superiore di Sanità, Rome, Italy
| | - Joel C. Watts
- Tanz Centre for Research in Neurodegenerative Diseases and Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | - Surachai Supattapone
- Departments of Biochemistry and Cell Biology at Darthmouth, Hanover, New Hampshire, United States of America
- Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, United States of America
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21
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Terry C, Harniman RL, Sells J, Wenborn A, Joiner S, Saibil HR, Miles MJ, Collinge J, Wadsworth JDF. Structural features distinguishing infectious ex vivo mammalian prions from non-infectious fibrillar assemblies generated in vitro. Sci Rep 2019; 9:376. [PMID: 30675000 PMCID: PMC6344479 DOI: 10.1038/s41598-018-36700-w] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Accepted: 11/23/2018] [Indexed: 01/19/2023] Open
Abstract
Seeded polymerisation of proteins forming amyloid fibres and their spread in tissues has been implicated in the pathogenesis of multiple neurodegenerative diseases: so called "prion-like" mechanisms. While ex vivo mammalian prions, composed of multichain assemblies of misfolded host-encoded prion protein (PrP), act as lethal infectious agents, PrP amyloid fibrils produced in vitro generally do not. The high-resolution structure of authentic infectious prions and the structural basis of prion strain diversity remain unknown. Here we use cryo-electron microscopy and atomic force microscopy to examine the structure of highly infectious PrP rods isolated from mouse brain in comparison to non-infectious recombinant PrP fibrils generated in vitro. Non-infectious recombinant PrP fibrils are 10 nm wide single fibres, with a double helical repeating substructure displaying small variations in adhesive force interactions across their width. In contrast, infectious PrP rods are 20 nm wide and contain two fibres, each with a double helical repeating substructure, separated by a central gap of 8-10 nm in width. This gap contains an irregularly structured material whose adhesive force properties are strikingly different to that of the fibres, suggestive of a distinct composition. The structure of the infectious PrP rods, which cause lethal neurodegeneration, readily differentiates them from all other protein assemblies so far characterised in other neurodegenerative diseases.
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Affiliation(s)
- Cassandra Terry
- MRC Prion Unit at UCL, UCL Institute of Prion Diseases, 33 Cleveland Street, London, W1W 7FF, UK
- London Metropolitan University, North Campus, Holloway Road, London, N7 8DB, UK
| | | | - Jessica Sells
- MRC Prion Unit at UCL, UCL Institute of Prion Diseases, 33 Cleveland Street, London, W1W 7FF, UK
- King's Centre for Stem Cells & Regenerative Medicine, King's College London, Guy's Campus, London, SE1 9RT, UK
| | - Adam Wenborn
- MRC Prion Unit at UCL, UCL Institute of Prion Diseases, 33 Cleveland Street, London, W1W 7FF, UK
| | - Susan Joiner
- MRC Prion Unit at UCL, UCL Institute of Prion Diseases, 33 Cleveland Street, London, W1W 7FF, UK
| | - Helen R Saibil
- Institute of Structural and Molecular Biology, Department of Biological Sciences, Birkbeck College, University of London, Malet Street, London, WC1E 7HX, UK
| | - Mervyn J Miles
- School of Physics, H.H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol, BS8 1TL, UK
| | - John Collinge
- MRC Prion Unit at UCL, UCL Institute of Prion Diseases, 33 Cleveland Street, London, W1W 7FF, UK.
| | - Jonathan D F Wadsworth
- MRC Prion Unit at UCL, UCL Institute of Prion Diseases, 33 Cleveland Street, London, W1W 7FF, UK.
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22
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Neuroinflammation, Microglia, and Cell-Association during Prion Disease. Viruses 2019; 11:v11010065. [PMID: 30650564 PMCID: PMC6356204 DOI: 10.3390/v11010065] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2018] [Revised: 01/09/2019] [Accepted: 01/10/2019] [Indexed: 02/06/2023] Open
Abstract
Prion disorders are transmissible diseases caused by a proteinaceous infectious agent that can infect the lymphatic and nervous systems. The clinical features of prion diseases can vary, but common hallmarks in the central nervous system (CNS) are deposition of abnormally folded protease-resistant prion protein (PrPres or PrPSc), astrogliosis, microgliosis, and neurodegeneration. Numerous proinflammatory effectors expressed by astrocytes and microglia are increased in the brain during prion infection, with many of them potentially damaging to neurons when chronically upregulated. Microglia are important first responders to foreign agents and damaged cells in the CNS, but these immune-like cells also serve many essential functions in the healthy CNS. Our current understanding is that microglia are beneficial during prion infection and critical to host defense against prion disease. Studies indicate that reduction of the microglial population accelerates disease and increases PrPSc burden in the CNS. Thus, microglia are unlikely to be a foci of prion propagation in the brain. In contrast, neurons and astrocytes are known to be involved in prion replication and spread. Moreover, certain astrocytes, such as A1 reactive astrocytes, have proven neurotoxic in other neurodegenerative diseases, and thus might also influence the progression of prion-associated neurodegeneration.
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23
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Kobayashi A, Qi Z, Shimazaki T, Munesue Y, Miyamoto T, Isoda N, Sawa H, Aoshima K, Kimura T, Mohri S, Kitamoto T, Yamashita T, Miyoshi I. Ganglioside Synthase Knockout Reduces Prion Disease Incubation Time in Mouse Models. THE AMERICAN JOURNAL OF PATHOLOGY 2018; 189:677-686. [PMID: 30553837 DOI: 10.1016/j.ajpath.2018.11.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Revised: 11/14/2018] [Accepted: 11/16/2018] [Indexed: 11/18/2022]
Abstract
Localization of the abnormal and normal isoforms of prion proteins to detergent-resistant membrane microdomains, lipid rafts, is important for the conformational conversion. Lipid rafts are enriched in sialic acid-containing glycosphingolipids (namely, gangliosides). Alteration in the ganglioside composition of lipid rafts can affect the localization of lipid raft-associated proteins. To investigate the role of gangliosides in the pathogenesis of prion diseases, we performed intracerebral transmission study of a scrapie prion strain Chandler and a Gerstmann-Sträussler-Scheinker syndrome prion strain Fukuoka-1 using various knockout mouse strains ablated with ganglioside synthase gene (ie, GD2/GM2 synthase, GD3 synthase, or GM3 synthase). After challenge with the Chandler strain, GD2/GM2 synthase knockout mice showed 20% reduction of incubation time, reduced prion protein deposition in the brain with attenuated glial reactions, and reduced localization of prion proteins to lipid rafts. These results raise the possibility that the gangliosides may have an important role in prion disease pathogenesis by affecting the localization of prion proteins to lipid rafts.
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Affiliation(s)
- Atsushi Kobayashi
- Laboratory of Comparative Pathology, Faculty of Veterinary Medicine, Sapporo, Japan.
| | - Zechen Qi
- Laboratory of Comparative Pathology, Faculty of Veterinary Medicine, Sapporo, Japan
| | - Taishi Shimazaki
- Laboratory of Comparative Pathology, Faculty of Veterinary Medicine, Sapporo, Japan
| | - Yoshiko Munesue
- Laboratory of Comparative Pathology, Faculty of Veterinary Medicine, Sapporo, Japan
| | - Tomomi Miyamoto
- Center for Experimental Animal Science, Graduate School of Medical Sciences, Nagoya City University, Nagoya, Japan
| | - Norikazu Isoda
- Global Station for Zoonosis Control, Global Institute for Collaborative Research and Education, Sapporo, Japan; Unit of Risk Analysis and Management, Sapporo, Japan
| | - Hirofumi Sawa
- Global Station for Zoonosis Control, Global Institute for Collaborative Research and Education, Sapporo, Japan; Division of Molecular Pathobiology, Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan
| | - Keisuke Aoshima
- Laboratory of Comparative Pathology, Faculty of Veterinary Medicine, Sapporo, Japan
| | - Takashi Kimura
- Laboratory of Comparative Pathology, Faculty of Veterinary Medicine, Sapporo, Japan
| | - Shirou Mohri
- Department of Neurological Science, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Tetsuyuki Kitamoto
- Department of Neurological Science, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Tadashi Yamashita
- Laboratory of Biochemistry, Graduate School of Veterinary Medicine, Azabu University, Sagamihara, Japan
| | - Ichiro Miyoshi
- Department of Laboratory Animal Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan
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24
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Abstract
The cellular prion protein, PrPC, is a small, cell surface glycoprotein with a function that is currently somewhat ill defined. It is also the key molecule involved in the family of neurodegenerative disorders called transmissible spongiform encephalopathies, which are also known as prion diseases. The misfolding of PrPC to a conformationally altered isoform, designated PrPTSE, is the main molecular process involved in pathogenesis and appears to precede many other pathologic and clinical manifestations of disease, including neuronal loss, astrogliosis, and cognitive loss. PrPTSE is also believed to be the major component of the infectious "prion," the agent responsible for disease transmission, and preparations of this protein can cause prion disease when inoculated into a naïve host. Thus, understanding the biochemical and biophysical properties of both PrPC and PrPTSE, and ultimately the mechanisms of their interconversion, is critical if we are to understand prion disease biology. Although entire books could be devoted to research pertaining to the protein, herein we briefly review the state of knowledge of prion biochemistry, including consideration of prion protein structure, function, misfolding, and dysfunction.
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Affiliation(s)
- Andrew C Gill
- School of Chemistry, Joseph Banks Laboratories, University of Lincoln, Lincoln, United Kingdom; Division of Neurobiology, The Roslin Institute and Royal (Dick) School of Veterinary Sciences, University of Edinburgh, Edinburgh, United Kingdom.
| | - Andrew R Castle
- Division of Neurobiology, The Roslin Institute and Royal (Dick) School of Veterinary Sciences, University of Edinburgh, Edinburgh, United Kingdom
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25
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Taguchi Y, Lu L, Marrero-Winkens C, Otaki H, Nishida N, Schatzl HM. Disulfide-crosslink scanning reveals prion-induced conformational changes and prion strain-specific structures of the pathological prion protein PrP Sc. J Biol Chem 2018; 293:12730-12740. [PMID: 29934306 PMCID: PMC6102138 DOI: 10.1074/jbc.ra117.001633] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 06/15/2018] [Indexed: 11/06/2022] Open
Abstract
Prions are composed solely of the pathological isoform (PrPSc) of the normal cellular prion protein (PrPC). Identification of different PrPSc structures is crucially important for understanding prion biology because the pathogenic properties of prions are hypothesized to be encoded in the structures of PrPSc However, these structures remain yet to be identified, because of the incompatibility of PrPSc with conventional high-resolution structural analysis methods. Previously, we reported that the region between the first and the second α-helix (H1∼H2) of PrPC might cooperate with the more C-terminal side region for efficient interactions with PrPSc From this starting point, we created a series of PrP variants with two cysteine substitutions (C;C-PrP) forming a disulfide-crosslink between H1∼H2 and the distal region of the third helix (Ctrm). We then assessed the conversion capabilities of the C;C-PrP variants in N2a cells infected with mouse-adapted scrapie prions (22L-ScN2a). Specifically, Cys substitutions at residues 165, 166, or 168 in H1∼H2 were combined with cysteine scanning along Ctrm residues 220-229. We found that C;C-PrPs are expressed normally with glycosylation patterns and subcellular localization similar to WT PrP, albeit differing in expression levels. Interestingly, some C;C-PrPs converted to protease-resistant isoforms in the 22L-ScN2a cells, but not in Fukuoka1 prion-infected cells. Crosslink patterns of convertible C;C-PrPs indicated a positional change of H1∼H2 toward Ctrm in PrPSc-induced conformational conversion. Given the properties of the C;C-PrPs reported here, we propose that these PrP variants may be useful tools for investigating prion strain-specific structures and structure-phenotype relationships of PrPSc.
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Affiliation(s)
- Yuzuru Taguchi
- Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta T2N 4Z6, Canada; Department of Molecular Microbiology and Immunology, Division of Cellular and Molecular Biology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8523, Japan.
| | - Li Lu
- Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta T2N 4Z6, Canada; Calgary Prion Research Unit, University of Calgary, Calgary, Alberta, Canada
| | - Cristobal Marrero-Winkens
- Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta T2N 4Z6, Canada; Calgary Prion Research Unit, University of Calgary, Calgary, Alberta, Canada
| | - Hiroki Otaki
- Center for Bioinformatics and Molecular Medicine, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8523, Japan
| | - Noriyuki Nishida
- Department of Molecular Microbiology and Immunology, Division of Cellular and Molecular Biology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8523, Japan
| | - Hermann M Schatzl
- Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta T2N 4Z6, Canada; Calgary Prion Research Unit, University of Calgary, Calgary, Alberta, Canada.
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Immunodetection of PrP Sc Using Western Immunoblotting Techniques. Methods Mol Biol 2018. [PMID: 28861782 DOI: 10.1007/978-1-4939-7244-9_5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
Western immunoblotting is a workhorse technique used in the prion field to analyze disease-associated forms of the prion protein, termed PrPSc. The biochemical stability of PrPSc aggregates combined with the increased resistance of prion infectivity to inactivation by various treatments that inactivate most other pathogens complicates the use of Western immunoblotting as a means to characterize PrPSc samples. In this chapter, we describe a method for Western immunoblot analysis of PrPSc with an emphasis on precautions to address the biochemical and biosafety considerations associated with this procedure.
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Cofactors influence the biological properties of infectious recombinant prions. Acta Neuropathol 2018; 135:179-199. [PMID: 29094186 DOI: 10.1007/s00401-017-1782-y] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Revised: 10/20/2017] [Accepted: 10/21/2017] [Indexed: 12/23/2022]
Abstract
Prion diseases are caused by a misfolding of the cellular prion protein (PrP) to a pathogenic isoform named PrPSc. Prions exist as strains, which are characterized by specific pathological and biochemical properties likely encoded in the three-dimensional structure of PrPSc. However, whether cofactors determine these different PrPSc conformations and how this relates to their specific biological properties is largely unknown. To understand how different cofactors modulate prion strain generation and selection, Protein Misfolding Cyclic Amplification was used to create a diversity of infectious recombinant prion strains by propagation in the presence of brain homogenate. Brain homogenate is known to contain these mentioned cofactors, whose identity is only partially known, and which facilitate conversion of PrPC to PrPSc. We thus obtained a mix of distinguishable infectious prion strains. Subsequently, we replaced brain homogenate, by different polyanionic cofactors that were able to drive the evolution of mixed prion populations toward specific strains. Thus, our results show that a variety of infectious recombinant prions can be generated in vitro and that their specific type of conformation, i.e., the strain, is dependent on the cofactors available during the propagation process. These observations have significant implications for understanding the pathogenesis of prion diseases and their ability to replicate in different tissues and hosts. Importantly, these considerations might apply to other neurodegenerative diseases for which different conformations of misfolded proteins have been described.
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28
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Sevillano AM, Fernández-Borges N, Younas N, Wang F, R. Elezgarai S, Bravo S, Vázquez-Fernández E, Rosa I, Eraña H, Gil D, Veiga S, Vidal E, Erickson-Beltran ML, Guitián E, Silva CJ, Nonno R, Ma J, Castilla J, R. Requena J. Recombinant PrPSc shares structural features with brain-derived PrPSc: Insights from limited proteolysis. PLoS Pathog 2018; 14:e1006797. [PMID: 29385212 PMCID: PMC5809102 DOI: 10.1371/journal.ppat.1006797] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Revised: 02/12/2018] [Accepted: 12/08/2017] [Indexed: 11/18/2022] Open
Abstract
Very solid evidence suggests that the core of full length PrPSc is a 4-rung β-solenoid, and that individual PrPSc subunits stack to form amyloid fibers. We recently used limited proteolysis to map the β-strands and connecting loops that make up the PrPSc solenoid. Using high resolution SDS-PAGE followed by epitope analysis, and mass spectrometry, we identified positions ~116/118, 133-134, 141, 152-153, 162, 169 and 179 (murine numbering) as Proteinase K (PK) cleavage sites in PrPSc. Such sites likely define loops and/or borders of β-strands, helping us to predict the threading of the β-solenoid. We have now extended this approach to recombinant PrPSc (recPrPSc). The term recPrPSc refers to bona fide recombinant prions prepared by PMCA, exhibiting infectivity with attack rates of ~100%. Limited proteolysis of mouse and bank vole recPrPSc species yielded N-terminally truncated PK-resistant fragments similar to those seen in brain-derived PrPSc, albeit with varying relative yields. Along with these fragments, doubly N- and C-terminally truncated fragments, in particular ~89/97-152, were detected in some recPrPSc preparations; similar fragments are characteristic of atypical strains of brain-derived PrPSc. Our results suggest a shared architecture of recPrPSc and brain PrPSc prions. The observed differences, in particular the distinct yields of specific PK-resistant fragments, are likely due to differences in threading which result in the specific biochemical characteristics of recPrPSc. Furthermore, recombinant PrPSc offers exciting opportunities for structural studies unachievable with brain-derived PrPSc.
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Affiliation(s)
- Alejandro M. Sevillano
- CIMUS Biomedical Research Institute and Department of Medical Sciences University of Santiago de Compostela-IDIS, Santiago de Compostela, Spain
- * E-mail: (AMS); (JRR)
| | | | - Neelam Younas
- CIMUS Biomedical Research Institute and Department of Medical Sciences University of Santiago de Compostela-IDIS, Santiago de Compostela, Spain
| | - Fei Wang
- Center for Neurodegenerative Science, Van Andel Research Institute, Grand Rapids, Michigan, United States of America
| | | | - Susana Bravo
- Proteomics Lab, IDIS, Santiago de Compostela, Spain
| | | | - Isaac Rosa
- CIMUS Biomedical Research Institute and Department of Medical Sciences University of Santiago de Compostela-IDIS, Santiago de Compostela, Spain
| | | | | | - Sonia Veiga
- CIMUS Biomedical Research Institute and Department of Medical Sciences University of Santiago de Compostela-IDIS, Santiago de Compostela, Spain
| | - Enric Vidal
- Priocat Laboratory, Centre de Recerca en Sanitat Animal (CReSA), UAB-IRTA, Barcelona, Catalonia, Spain
| | | | - Esteban Guitián
- Mass spectrometry Core Facility, RIAIDT, University of Santiago de Compostela, Santiago de Compostela, Spain
| | - Christopher J. Silva
- USDA, ARS Western Regional Research Center, Albany, California, United States of America
| | - Romolo Nonno
- Department of Veterinary Public Health and Food Safety, Istituto Superiore di Sanità, Rome, Italy
| | - Jiyan Ma
- Center for Neurodegenerative Science, Van Andel Research Institute, Grand Rapids, Michigan, United States of America
| | | | - Jesús R. Requena
- CIMUS Biomedical Research Institute and Department of Medical Sciences University of Santiago de Compostela-IDIS, Santiago de Compostela, Spain
- * E-mail: (AMS); (JRR)
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Kanata E, Arsenakis M, Sklaviadis T. Caprine PrP variants harboring Asp-146, His-154 and Gln-211 alleles display reduced convertibility upon interaction with pathogenic murine prion protein in scrapie infected cells. Prion 2017; 10:391-408. [PMID: 27537339 DOI: 10.1080/19336896.2016.1199312] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Scrapie, the prion disease of sheep and goats, is a devastating malady of small ruminants. Due to its infectious nature, epidemic outbreaks may occur in flocks/herds consisting of highly susceptible animals. Field studies identified scrapie-protective caprine PrP variants, harboring specific single amino acid changes (Met-142, Arg-143, Asp-146, Ser-146, His-154, Gln-211 and Lys-222). Their effects are under further evaluation, and aim to determine the most protective allele. We assessed some of these variants (Asp-146, His-154, Gln-211 and Lys-222), after their exogenous expression as murine-caprine chimeras in a scrapie- infected murine cell line. We report that exogenously expressed PrPs undergo conformational conversion upon interaction with the endogenous pathological murine prion protein (PrPSC), which results in the detection of goat-specific and partially PK-resistant moieties. These moieties display a PK-resistance pattern distinct from the one detected in natural goat scrapie cases. Within this cellular model, distinct conformational conversion potentials were assigned to the tested variants. Molecules carrying the Asp-146, His-154 and Gln-211 alleles showed significantly lower conversion levels compared to wild type, confirming their protective effects against scrapie. Although we utilized a heterologous conversion system, this is to our knowledge, the first study of caprine PrP variants in a cellular context of scrapie, that confirms the protective effects of some of the studied alleles.
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Affiliation(s)
- Eirini Kanata
- a Department of Genetics , Development and Molecular Biology, School of Biology, Aristotle University of Thessaloniki , Thessaloniki , Greece.,b School of Pharmacy , Aristotle University of Thessaloniki , Thessaloniki , Greece
| | - Minas Arsenakis
- a Department of Genetics , Development and Molecular Biology, School of Biology, Aristotle University of Thessaloniki , Thessaloniki , Greece
| | - Theodoros Sklaviadis
- b School of Pharmacy , Aristotle University of Thessaloniki , Thessaloniki , Greece
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30
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Igel-Egalon A, Moudjou M, Martin D, Busley A, Knäpple T, Herzog L, Reine F, Lepejova N, Richard CA, Béringue V, Rezaei H. Reversible unfolding of infectious prion assemblies reveals the existence of an oligomeric elementary brick. PLoS Pathog 2017; 13:e1006557. [PMID: 28880932 PMCID: PMC5589264 DOI: 10.1371/journal.ppat.1006557] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Accepted: 07/28/2017] [Indexed: 11/20/2022] Open
Abstract
Mammalian prions, the pathogens that cause transmissible spongiform encephalopathies, propagate by self-perpetuating the structural information stored in the abnormally folded, aggregated conformer (PrPSc) of the host-encoded prion protein (PrPC). To date, no structural model related to prion assembly organization satisfactorily describes how strain-specified structural information is encoded and by which mechanism this information is transferred to PrPC. To achieve progress on this issue, we correlated the PrPSc quaternary structural transition from three distinct prion strains during unfolding and refolding with their templating activity. We reveal the existence of a mesoscopic organization in PrPSc through the packing of a highly stable oligomeric elementary subunit (suPrP), in which the strain structural determinant (SSD) is encoded. Once kinetically trapped, this elementary subunit reversibly loses all replicative information. We demonstrate that acquisition of the templating interface and infectivity requires structural rearrangement of suPrP, in concert with its condensation. The existence of such an elementary brick scales down the SSD support to a small oligomer and provide a basis of reflexion for prion templating process and propagation. Prions are self-propagating assemblies with all necessary and sufficient replicative information stored in the 3D structure of the misfolded form of PrP called PrPSc. Since the emergence of the prion theory in the 80s, many attempts have been done to identify prion replicative information at molecular scale. Different models have been constructed based on a broad panel of experimental observations and some of them predict the existence of periodic elements constituting prion assemblies. Here, by using partial unfolding approaches, we trapped an oligomeric conformer that we called suPrP, which could constitute the elementary brick of prion assemblies. Once isolated, this elementary brick is devoid of infectivity. However, it becomes infectious once condensated into larger assemblies. The identification of the elementary PrP building block provides a new structural basis for understanding prion replicative information storage and spreading.
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Affiliation(s)
- Angélique Igel-Egalon
- INRA, Université Paris-Saclay, UR892, Virologie Immunologie Moléculaires, Jouy-en-Josas, France
| | - Mohammed Moudjou
- INRA, Université Paris-Saclay, UR892, Virologie Immunologie Moléculaires, Jouy-en-Josas, France
| | - Davy Martin
- INRA, Université Paris-Saclay, UR892, Virologie Immunologie Moléculaires, Jouy-en-Josas, France
| | - Alexandra Busley
- INRA, Université Paris-Saclay, UR892, Virologie Immunologie Moléculaires, Jouy-en-Josas, France
| | - Tina Knäpple
- INRA, Université Paris-Saclay, UR892, Virologie Immunologie Moléculaires, Jouy-en-Josas, France
| | - Laetitia Herzog
- INRA, Université Paris-Saclay, UR892, Virologie Immunologie Moléculaires, Jouy-en-Josas, France
| | - Fabienne Reine
- INRA, Université Paris-Saclay, UR892, Virologie Immunologie Moléculaires, Jouy-en-Josas, France
| | - Nad’a Lepejova
- INRA, Université Paris-Saclay, UR892, Virologie Immunologie Moléculaires, Jouy-en-Josas, France
| | - Charles-Adrien Richard
- INRA, Université Paris-Saclay, UR892, Virologie Immunologie Moléculaires, Jouy-en-Josas, France
| | - Vincent Béringue
- INRA, Université Paris-Saclay, UR892, Virologie Immunologie Moléculaires, Jouy-en-Josas, France
- * E-mail: (VB); (HR)
| | - Human Rezaei
- INRA, Université Paris-Saclay, UR892, Virologie Immunologie Moléculaires, Jouy-en-Josas, France
- * E-mail: (VB); (HR)
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31
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Elezgarai SR, Fernández-Borges N, Eraña H, Sevillano AM, Charco JM, Harrathi C, Saá P, Gil D, Kong Q, Requena JR, Andréoletti O, Castilla J. Generation of a new infectious recombinant prion: a model to understand Gerstmann-Sträussler-Scheinker syndrome. Sci Rep 2017; 7:9584. [PMID: 28851967 PMCID: PMC5575253 DOI: 10.1038/s41598-017-09489-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Accepted: 07/10/2017] [Indexed: 12/15/2022] Open
Abstract
Human transmissible spongiform encephalopathies (TSEs) or prion diseases are a group of fatal neurodegenerative disorders that include Kuru, Creutzfeldt-Jakob disease, Gerstmann-Sträussler-Scheinker syndrome (GSS), and fatal familial insomnia. GSS is a genetically determined TSE caused by a range of mutations within the prion protein (PrP) gene. Several animal models, based on the expression of PrPs carrying mutations analogous to human heritable prion diseases, support that mutations might predispose PrP to spontaneously misfold. An adapted Protein Misfolding Cyclic Amplification methodology based on the use of human recombinant PrP (recPMCA) generated different self-propagating misfolded proteins spontaneously. These were characterized biochemically and structurally, and the one partially sharing some of the GSS PrPSc molecular features was inoculated into different animal models showing high infectivity. This constitutes an infectious recombinant prion which could be an invaluable model for understanding GSS. Moreover, this study proves the possibility to generate recombinant versions of other human prion diseases that could provide a further understanding on the molecular features of these devastating disorders.
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Affiliation(s)
- Saioa R Elezgarai
- CIC bioGUNE, Parque tecnológico de Bizkaia, Derio, 48160, Bizkaia, Spain
| | | | - Hasier Eraña
- CIC bioGUNE, Parque tecnológico de Bizkaia, Derio, 48160, Bizkaia, Spain
| | - Alejandro M Sevillano
- CIMUS Biomedical Research Institute, University of Santiago de Compostela-IDIS, Santiago de Compostela, Spain
| | - Jorge M Charco
- CIC bioGUNE, Parque tecnológico de Bizkaia, Derio, 48160, Bizkaia, Spain
| | - Chafik Harrathi
- CIC bioGUNE, Parque tecnológico de Bizkaia, Derio, 48160, Bizkaia, Spain
| | - Paula Saá
- American Red Cross, Gaithersburg, MD, USA
| | - David Gil
- CIC bioGUNE, Parque tecnológico de Bizkaia, Derio, 48160, Bizkaia, Spain
| | - Qingzhong Kong
- Department of Pathology, Case Western Reserve University, Cleveland, OH, 44106, USA
| | - Jesús R Requena
- CIMUS Biomedical Research Institute, University of Santiago de Compostela-IDIS, Santiago de Compostela, Spain
| | - Olivier Andréoletti
- Ecole Nationale du Veterinaire, Service de Pathologie du Bétail, Toulouse, 31076, France
| | - Joaquín Castilla
- CIC bioGUNE, Parque tecnológico de Bizkaia, Derio, 48160, Bizkaia, Spain. .,IKERBASQUE, Basque Foundation for Science, Bilbao, 48011, Bizkaia, Spain.
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32
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Requena JR, Wille H. The Structure of the Infectious Prion Protein and Its Propagation. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2017; 150:341-359. [PMID: 28838667 DOI: 10.1016/bs.pmbts.2017.06.009] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The prion diseases, which include Creutzfeldt-Jakob disease in humans, chronic wasting disease in cervids (i.e., deer, elk, moose, and reindeer), bovine spongiform encephalopathy in cattle, as well as sheep and goat scrapie, are caused by the conversion of the cellular prion protein (PrPC) into a disease-causing conformer (PrPSc). PrPC is a regular, GPI-anchored protein that is expressed on the cell surface of neurons and many other cell types. The structure of PrPC is well studied, based on analyses of recombinant PrP, which is thought to mimic the structure of native PrPC. The mature protein contains an N-terminal, unfolded domain and a C-terminal, globular domain that consists of three α-helices and only a small, two-stranded β-sheet. In contrast, PrPSc was found to contain predominantly β-structure and to aggregate into a variety of quaternary structures, such as oligomers, amorphous aggregates, amyloid fibrils, and two-dimensional crystals. The tendency of PrPSc to aggregate into these diverse forms is also responsible for our incomplete knowledge about its molecular structure. Nevertheless, the repeating nature of the more regular PrPSc aggregates has provided informative insights into the structure of the infectious conformer, albeit at limited resolution. These data established a four-rung β-solenoid architecture as the main element of its structure. Moreover, the four-rung β-solenoid architecture provides a molecular framework for an autocatalytic propagation mechanism, which could explain the conversion of PrPC into PrPSc.
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Affiliation(s)
- Jesús R Requena
- CIMUS Biomedical Research Institute, University of Santiago de Compostela-IDIS, Santiago de Compostela, Spain
| | - Holger Wille
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada.
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Abstract
Prion diseases are characterized by the deposition of amyloids, misfolded conformers of the prion protein. The misfolded conformation is self-replicating, by a mechanism solely enciphered in the conformation of the protein. Because of low solubility and heterogeneous aggregate sizes, the detailed atomic structure of the infectious isoform is still unknown. Progress has, however, been made, and has allowed insights into the structural and disease-related mechanisms of prions. Many structural models have been proposed, and a number of them support a consensus trimeric β-helical model, significantly more complex than simple amyloid models. There is evidence that such complexity may be a necessary property of prion structure. Knowledge of the structure of prions will provide a greater understanding of the protein isoform conversion mechanism, and could eventually lead to rationally designed intervention strategies.
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Affiliation(s)
- Gerald Stubbs
- Department of Biological Sciences and Center for Structural Biology, Vanderbilt University, Nashville, Tennessee 53723
| | - Jan Stöhr
- Institute for Neurodegenerative Diseases, Department of Neurology, Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, California 94143
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Aguilar-Calvo P, Xiao X, Bett C, Eraña H, Soldau K, Castilla J, Nilsson KPR, Surewicz WK, Sigurdson CJ. Post-translational modifications in PrP expand the conformational diversity of prions in vivo. Sci Rep 2017; 7:43295. [PMID: 28272426 PMCID: PMC5341109 DOI: 10.1038/srep43295] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2016] [Accepted: 01/23/2017] [Indexed: 12/02/2022] Open
Abstract
Misfolded prion protein aggregates (PrPSc) show remarkable structural diversity and are associated with highly variable disease phenotypes. Similarly, other proteins, including amyloid-β, tau, α-synuclein, and serum amyloid A, misfold into distinct conformers linked to different clinical diseases through poorly understood mechanisms. Here we use mice expressing glycophosphatidylinositol (GPI)-anchorless prion protein, PrPC, together with hydrogen-deuterium exchange coupled with mass spectrometry (HXMS) and a battery of biochemical and biophysical tools to investigate how post-translational modifications impact the aggregated prion protein properties and disease phenotype. Four GPI-anchorless prion strains caused a nearly identical clinical and pathological disease phenotype, yet maintained their structural diversity in the anchorless state. HXMS studies revealed that GPI-anchorless PrPSc is characterized by substantially higher protection against hydrogen/deuterium exchange in the C-terminal region near the N-glycan sites, suggesting this region had become more ordered in the anchorless state. For one strain, passage of GPI-anchorless prions into wild type mice led to the emergence of a novel strain with a unique biochemical and phenotypic signature. For the new strain, histidine hydrogen-deuterium mass spectrometry revealed altered packing arrangements of β-sheets that encompass residues 139 and 186 of PrPSc. These findings show how variation in post-translational modifications may explain the emergence of new protein conformations in vivo and also provide a basis for understanding how the misfolded protein structure impacts the disease.
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Affiliation(s)
| | - Xiangzhu Xiao
- Department of Physiology and Biophysics, Case Western Reserve University, Cleveland, OH 44116, USA
| | - Cyrus Bett
- Departments of Pathology and Medicine, UC San Diego, La Jolla, CA 92093-0612, USA
| | - Hasier Eraña
- CIC bioGUNE, Parque Tecnológico de Bizkaia, Ed. 800, Derio 48160, Spain
| | - Katrin Soldau
- Departments of Pathology and Medicine, UC San Diego, La Jolla, CA 92093-0612, USA
| | - Joaquin Castilla
- CIC bioGUNE, Parque Tecnológico de Bizkaia, Ed. 800, Derio 48160, Spain.,IKERBASQUE, Basque Foundation for Science, 48013 Bilbao, Spain
| | - K Peter R Nilsson
- Department of Physics, Chemistry, and Biology, Linköping University, Linköping 581 83, Sweden
| | - Witold K Surewicz
- Department of Physiology and Biophysics, Case Western Reserve University, Cleveland, OH 44116, USA
| | - Christina J Sigurdson
- Departments of Pathology and Medicine, UC San Diego, La Jolla, CA 92093-0612, USA.,Department of Pathology, Immunology, and Microbiology, UC Davis, Davis, CA 95616, USA
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35
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Munoz-Montesino C, Sizun C, Moudjou M, Herzog L, Reine F, Igel-Egalon A, Barbereau C, Chapuis J, Ciric D, Laude H, Béringue V, Rezaei H, Dron M. A stretch of residues within the protease-resistant core is not necessary for prion structure and infectivity. Prion 2017; 11:25-30. [PMID: 28281924 DOI: 10.1080/19336896.2016.1274851] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Mapping out regions of PrP influencing prion conversion remains a challenging issue complicated by the lack of prion structure. The portion of PrP associated with infectivity contains the α-helical domain of the correctly folded protein and turns into a β-sheet-rich insoluble core in prions. Deletions performed so far inside this segment essentially prevented the conversion. Recently we found that deletion of the last C-terminal residues of the helix H2 was fully compatible with prion conversion in the RK13-ovPrP cell culture model, using 3 different infecting strains. This was in agreement with preservation of the overall PrPC structure even after removal of up to one-third of this helix. Prions with internal deletion were infectious for cells and mice expressing the wild-type PrP and they retained prion strain-specific characteristics. We thus identified a piece of the prion domain that is neither necessary for the conformational transition of PrPC nor for the formation of a stable prion structure.
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Affiliation(s)
| | - Christina Sizun
- b Institut de Chimie des Substances Naturelles, CNRS, Université Paris Saclay , Gif-sur-Yvette , France
| | | | - Laetitia Herzog
- a VIM, INRA, Université Paris-Saclay , Jouy-en-Josas , France
| | - Fabienne Reine
- a VIM, INRA, Université Paris-Saclay , Jouy-en-Josas , France
| | | | | | - Jérôme Chapuis
- a VIM, INRA, Université Paris-Saclay , Jouy-en-Josas , France
| | - Danica Ciric
- a VIM, INRA, Université Paris-Saclay , Jouy-en-Josas , France
| | - Hubert Laude
- a VIM, INRA, Université Paris-Saclay , Jouy-en-Josas , France
| | | | - Human Rezaei
- a VIM, INRA, Université Paris-Saclay , Jouy-en-Josas , France
| | - Michel Dron
- a VIM, INRA, Université Paris-Saclay , Jouy-en-Josas , France
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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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The Structure of Mammalian Prions and Their Aggregates. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2016; 329:277-301. [PMID: 28109330 DOI: 10.1016/bs.ircmb.2016.08.013] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Prion diseases, such as Creutzfeldt-Jakob disease in humans, bovine spongiform encephalopathy in cattle, chronic wasting disease in cervids (i.e., deer, elk, moose, and reindeer), and sheep scrapie, are caused by the misfolding of the cellular prion protein (PrPC) into a disease-causing conformer (PrPSc). PrPC is a normal, GPI-anchored protein that is expressed on the surface of neurons and other cell types. The structure of PrPC is well understood, based on studies of recombinant PrP, which closely mimics the structure of native PrPC. In contrast, PrPSc is prone to aggregate into a variety of quaternary structures, such as oligomers, amorphous aggregates, and amyloid fibrils. The propensity of PrPSc to assemble into these diverse forms of aggregates is also responsible for our limited knowledge about its structure. Then again, the repeating nature of certain regular PrPSc aggregates has allowed (lower resolution) insights into the structure of the infectious conformer, establishing a four-rung β-solenoid structure as a key element of its architecture.
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Abstract
Within the mammalian prion field, the existence of recombinant prion protein (PrP) conformers with self-replicating (ie. autocatalytic) activity in vitro but little to no infectious activity in vivo challenges a key prediction of the protein-only hypothesis of prion replication--that autocatalytic PrP conformers should be infectious. To understand this dissociation of autocatalysis from infectivity, we recently performed a structural and functional comparison between a highly infectious and non-infectious pair of autocatalytic recombinant PrP conformers derived from the same initial prion strain. (1) We identified restricted, C-terminal structural differences between these 2 conformers and provided evidence that these relatively subtle differences prevent the non-infectious conformer from templating the conversion of native PrP(C) substrates containing a glycosylphosphatidylinositol (GPI) anchor. (1) In this article we discuss a model, consistent with these findings, in which recombinant PrP, lacking post-translational modifications and associated folding constraints, is capable of adopting a wide variety of autocatalytic conformations. Only a subset of these recombinant conformers can be adopted by post-translationally modified native PrP(C), and this subset represents the recombinant conformers with high specific infectivity. We examine this model's implications for the generation of highly infectious recombinant prions and the protein-only hypothesis of prion replication.
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Affiliation(s)
- Geoffrey P Noble
- a Departments of Biochemistry and Medicine ; Geisel School of Medicine at Dartmouth College ; Hanover , NH USA
| | - Surachai Supattapone
- a Departments of Biochemistry and Medicine ; Geisel School of Medicine at Dartmouth College ; Hanover , NH USA
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The Structural Architecture of an Infectious Mammalian Prion Using Electron Cryomicroscopy. PLoS Pathog 2016; 12:e1005835. [PMID: 27606840 PMCID: PMC5015997 DOI: 10.1371/journal.ppat.1005835] [Citation(s) in RCA: 108] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Accepted: 08/01/2016] [Indexed: 12/31/2022] Open
Abstract
The structure of the infectious prion protein (PrPSc), which is responsible for Creutzfeldt-Jakob disease in humans and bovine spongiform encephalopathy, has escaped all attempts at elucidation due to its insolubility and propensity to aggregate. PrPSc replicates by converting the non-infectious, cellular prion protein (PrPC) into the misfolded, infectious conformer through an unknown mechanism. PrPSc and its N-terminally truncated variant, PrP 27–30, aggregate into amorphous aggregates, 2D crystals, and amyloid fibrils. The structure of these infectious conformers is essential to understanding prion replication and the development of structure-based therapeutic interventions. Here we used the repetitive organization inherent to GPI-anchorless PrP 27–30 amyloid fibrils to analyze their structure via electron cryomicroscopy. Fourier-transform analyses of averaged fibril segments indicate a repeating unit of 19.1 Å. 3D reconstructions of these fibrils revealed two distinct protofilaments, and, together with a molecular volume of 18,990 Å3, predicted the height of each PrP 27–30 molecule as ~17.7 Å. Together, the data indicate a four-rung β-solenoid structure as a key feature for the architecture of infectious mammalian prions. Furthermore, they allow to formulate a molecular mechanism for the replication of prions. Knowledge of the prion structure will provide important insights into the self-propagation mechanisms of protein misfolding. The structure of the infectious prion (PrPSc), which is responsible for Creutzfeldt-Jakob disease in humans and bovine spongiform encephalopathy, has escaped all attempts at elucidation due to its propensity to aggregate. Here, we use the repetitive organization inherent in amyloid fibrils to analyze the structure of GPI-anchorless PrP 27–30 via electron cryomicroscopy. Fourier-transform analysis of averaged fibril segments indicates a repeating unit of 19.1 Å. In agreement with this observation, 3D reconstructions reveal that each fibril contains two distinct protofilaments and that the height of each PrP 27–30 molecule in these fibrils is ~17.7 Å. Together the data indicate a four-rung β-solenoid structure as a key feature for the architecture of infectious mammalian prions. The data conflict with all previous models for the structure of PrPSc and allow the formulation of a molecular mechanism for the replication of prions.
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Generating Bona Fide Mammalian Prions with Internal Deletions. J Virol 2016; 90:6963-6975. [PMID: 27226369 DOI: 10.1128/jvi.00555-16] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Accepted: 05/14/2016] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED Mammalian prions are PrP proteins with altered structures causing transmissible fatal neurodegenerative diseases. They are self-perpetuating through formation of beta-sheet-rich assemblies that seed conformational change of cellular PrP. Pathological PrP usually forms an insoluble protease-resistant core exhibiting beta-sheet structures but no more alpha-helical content, loosing the three alpha-helices contained in the correctly folded PrP. The lack of a high-resolution prion structure makes it difficult to understand the dynamics of conversion and to identify elements of the protein involved in this process. To determine whether completeness of residues within the protease-resistant domain is required for prions, we performed serial deletions in the helix H2 C terminus of ovine PrP, since this region has previously shown some tolerance to sequence changes without preventing prion replication. Deletions of either four or five residues essentially preserved the overall PrP structure and mutant PrP expressed in RK13 cells were efficiently converted into bona fide prions upon challenge by three different prion strains. Remarkably, deletions in PrP facilitated the replication of two strains that otherwise do not replicate in this cellular context. Prions with internal deletion were self-propagating and de novo infectious for naive homologous and wild-type PrP-expressing cells. Moreover, they caused transmissible spongiform encephalopathies in mice, with similar biochemical signatures and neuropathologies other than the original strains. Prion convertibility and transfer of strain-specific information are thus preserved despite shortening of an alpha-helix in PrP and removal of residues within prions. These findings provide new insights into sequence/structure/infectivity relationship for prions. IMPORTANCE Prions are misfolded PrP proteins that convert the normal protein into a replicate of their own abnormal form. They are responsible for invariably fatal neurodegenerative disorders. Other aggregation-prone proteins appear to have a prion-like mode of expansion in brains, such as in Alzheimer's or Parkinson's diseases. To date, the resolution of prion structure remains elusive. Thus, to genetically define the landscape of regions critical for prion conversion, we tested the effect of short deletions. We found that, surprisingly, removal of a portion of PrP, the C terminus of alpha-helix H2, did not hamper prion formation but generated infectious agents with an internal deletion that showed characteristics essentially similar to those of original infecting strains. Thus, we demonstrate that completeness of the residues inside prions is not necessary for maintaining infectivity and the main strain-specific information, while reporting one of the few if not the only bona fide prions with an internal deletion.
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Sano K, Atarashi R, Nishida N. Structural conservation of prion strain specificities in recombinant prion protein fibrils in real-time quaking-induced conversion. Prion 2016; 9:237-43. [PMID: 26284507 PMCID: PMC4601500 DOI: 10.1080/19336896.2015.1062201] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
A major unsolved issue of prion biology is the existence of multiple strains with distinct phenotypes and this strain phenomenon is postulated to be associated with the conformational diversity of the abnormal prion protein (PrPSc). Real-time quaking-induced conversion (RT-QUIC) assay that uses Escherichia coli-derived recombinant prion protein (rPrP) for the sensitive detection of PrPSc results in the formation of rPrP-fibrils seeded with various strains. We demonstrated that there are differences in the secondary structures, especially in the β-sheets, and conformational stability between 2 rPrP-fibrils seeded with either Chandler or 22L strains in the first round of RT-QUIC. In particular, the differences in conformational properties of these 2 rPrP-fibrils were common to those of the original PrPSc. However, the strain specificities of rPrP-fibrils seen in the first round were lost in subsequent rounds. Instead, our findings suggest that nonspecific fibrils became the major species, probable owing to their selective growth advantage in the RT-QUIC. This study shows that at least some strain-specific conformational properties of the original PrPSc can be transmitted to rPrP-fibrils in vitro, but further conservation appears to require unknown cofactors or environmental conditions or both.
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Affiliation(s)
- Kazunori Sano
- a Department of Physiology and Pharmacology; Faculty of Pharmaceutical Sciences; Fukuoka University ; Fukuoka, Japan
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Saijo E, Hughson AG, Raymond GJ, Suzuki A, Horiuchi M, Caughey B. PrPSc-Specific Antibody Reveals C-Terminal Conformational Differences between Prion Strains. J Virol 2016; 90:4905-4913. [PMID: 26937029 PMCID: PMC4859706 DOI: 10.1128/jvi.00088-16] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Accepted: 02/19/2016] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED Understanding the structure of PrP(Sc) and its strain variation has been one of the major challenges in prion disease biology. To study the strain-dependent conformations of PrP(Sc), we purified proteinase-resistant PrP(Sc) (PrP(RES)) from mouse brains with three different murine-adapted scrapie strains (Chandler, 22L, and Me7) and systematically tested the accessibility of epitopes of a wide range of anti-PrP and anti-PrP(Sc) specific antibodies by indirect enzyme-linked immunosorbent assay (ELISA). We found that epitopes of most anti-PrP antibodies were hidden in the folded structure of PrP(RES), even though these epitopes are revealed with guanidine denaturation. However, reactivities to a PrP(Sc)-specific conformational C-terminal antibody showed significant differences among the three different prion strains. Our results provide evidence for strain-dependent conformational variation near the C termini of molecules within PrP(Sc) multimers. IMPORTANCE It has long been apparent that prion strains can have different conformations near the N terminus of the PrP(Sc) protease-resistant core. Here, we show that a C-terminal conformational PrP(Sc)-specific antibody reacts differently to three murine-adapted scrapie strains. These results suggest, in turn, that conformational differences in the C terminus of PrP(Sc) also contribute to the phenotypic distinction between prion strains.
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Affiliation(s)
- Eri Saijo
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, USA
| | - Andrew G Hughson
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, USA
| | - Gregory J Raymond
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, USA
| | - Akio Suzuki
- Laboratory of Veterinary Hygiene, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
| | - Motohiro Horiuchi
- Laboratory of Veterinary Hygiene, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
| | - Byron Caughey
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, USA
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Silva CJ, Erickson-Beltran ML, Dynin IC. Covalent Surface Modification of Prions: A Mass Spectrometry-Based Means of Detecting Distinctive Structural Features of Prion Strains. Biochemistry 2016; 55:894-902. [PMID: 26786805 DOI: 10.1021/acs.biochem.5b01068] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Prions (PrP(Sc)) are molecular pathogens that are able to convert the isosequential normal cellular prion protein (PrP(C)) into a prion. The only demonstrated difference between PrP(C) and PrP(Sc) is conformational: they are isoforms. A given host can be infected by more than one kind or strain of prion. Five strains of hamster-adapted scrapie [Sc237 (=263K), drowsy, 139H, 22AH, and 22CH] and recombinant PrP were reacted with five different concentrations (0, 1, 5, 10, and 20 mM) of reagent (N-hydroxysuccinimide ester of acetic acid) that acetylates lysines. The extent of lysine acetylation was quantitated by mass spectrometry. The lysines in rPrP react similarly. The lysines in the strains react differently from one another in a given strain and react differently when strains are compared. Lysines in the C-terminal region of prions have different strain-dependent reactivity. The results are consistent with a recently proposed model for the structure of a prion. This model proposes that prions are composed of a four-rung β-solenoid structure comprised of four β-sheets that are joined by loops and turns of amino acids. Variation in the amino acid composition of the loops and β-sheet structures is thought to result in different strains of prions.
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Affiliation(s)
- Christopher J Silva
- Western Regional Research Center, United States Department of Agriculture , Albany, California 94710, United States
| | - Melissa L Erickson-Beltran
- Western Regional Research Center, United States Department of Agriculture , Albany, California 94710, United States
| | - Irina C Dynin
- Western Regional Research Center, United States Department of Agriculture , Albany, California 94710, United States
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Detection of Atypical H-Type Bovine Spongiform Encephalopathy and Discrimination of Bovine Prion Strains by Real-Time Quaking-Induced Conversion. J Clin Microbiol 2016; 54:676-86. [PMID: 26739160 DOI: 10.1128/jcm.02731-15] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Accepted: 12/25/2015] [Indexed: 12/30/2022] Open
Abstract
Prion diseases of cattle include the classical bovine spongiform encephalopathy (C-BSE) and the atypical H-type BSE (H-BSE) and L-type BSE (L-BSE) strains. Although the C- and L-BSE strains can be detected and discriminated by ultrasensitive real-time quaking-induced conversion (RT-QuIC) assays, no such test has yet been described for the detection of H-BSE or the discrimination of each of the major bovine prion strains. Here, we demonstrate an RT-QuIC assay for H-BSE that can detect as little as 10(-9) dilutions of brain tissue and neat cerebrospinal fluid samples from clinically affected cattle. Moreover, comparisons of the reactivities with different recombinant prion protein substrates and/or immunoblot band profiles of proteinase K-treated RT-QuIC reaction products indicated that H-, L-, and C-BSE have distinctive prion seeding activities and can be discriminated by RT-QuIC on this basis.
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Abstract
Prion diseases are a heterogeneous class of fatal neurodegenerative disorders associated with misfolding of host cellular prion protein (PrP(C)) into a pathological isoform, termed PrP(Sc). Prion diseases affect various mammals, including humans, and effective treatments are not available. Prion diseases are distinguished from other protein misfolding disorders - such as Alzheimer's or Parkinson's disease - in that they are infectious. Prion diseases occur sporadically without any known exposure to infected material, and hereditary cases resulting from rare mutations in the prion protein have also been documented. The mechanistic underpinnings of prion and other neurodegenerative disorders remain poorly understood. Various proteomics techniques have been instrumental in early PrP(Sc) detection, biomarker discovery, elucidation of PrP(Sc) structure and mapping of biochemical pathways affected by pathogenesis. Moving forward, proteomics approaches will likely become more integrated into the clinical and research settings for the rapid diagnosis and characterization of prion pathogenesis.
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Affiliation(s)
- Roger A Moore
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, NIH,NIAID, Hamilton, MT 59840, USA
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Noble GP, Wang DW, Walsh DJ, Barone JR, Miller MB, Nishina KA, Li S, Supattapone S. A Structural and Functional Comparison Between Infectious and Non-Infectious Autocatalytic Recombinant PrP Conformers. PLoS Pathog 2015; 11:e1005017. [PMID: 26125623 PMCID: PMC4488359 DOI: 10.1371/journal.ppat.1005017] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Accepted: 06/09/2015] [Indexed: 11/30/2022] Open
Abstract
Infectious prions contain a self-propagating, misfolded conformer of the prion protein termed PrPSc. A critical prediction of the protein-only hypothesis is that autocatalytic PrPSc molecules should be infectious. However, some autocatalytic recombinant PrPSc molecules have low or undetectable levels of specific infectivity in bioassays, and the essential determinants of recombinant prion infectivity remain obscure. To identify structural and functional features specifically associated with infectivity, we compared the properties of two autocatalytic recombinant PrP conformers derived from the same original template, which differ by >105-fold in specific infectivity for wild-type mice. Structurally, hydrogen/deuterium exchange mass spectrometry (DXMS) studies revealed that solvent accessibility profiles of infectious and non-infectious autocatalytic recombinant PrP conformers are remarkably similar throughout their protease-resistant cores, except for two domains encompassing residues 91-115 and 144-163. Raman spectroscopy and immunoprecipitation studies confirm that these domains adopt distinct conformations within infectious versus non-infectious autocatalytic recombinant PrP conformers. Functionally, in vitro prion propagation experiments show that the non-infectious conformer is unable to seed mouse PrPC substrates containing a glycosylphosphatidylinositol (GPI) anchor, including native PrPC. Taken together, these results indicate that having a conformation that can be specifically adopted by post-translationally modified PrPC molecules is an essential determinant of biological infectivity for recombinant prions, and suggest that this ability is associated with discrete features of PrPSc structure. A key prediction of the prion hypothesis is that autocatalytic, misfolded PrPSc molecules should be highly infectious. Various recombinant PrPSc conformers are able to self-propagate in vitro, yet paradoxically only some of these conformers possess significant levels of specific infectivity in bioassays. Here we use two closely-matched autocatalytic recombinant PrP conformers that share the same origin but differ by >105-fold in specific infectivity to study the molecular basis of prion infectivity. We show that infectious and non-infectious autocatalytic recombinant PrP conformers have subtle structural differences, and that GPI-anchored PrP substrate molecules can only adopt the infectious PrPSc conformation. We conclude that post-translational modifications of host PrPC molecules play a critical role in restricting the range of recombinant PrPSc conformers that are biologically infectious.
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Affiliation(s)
- Geoffrey P. Noble
- Departments of Biochemistry and Medicine, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, United States of America
| | - Daphne W. Wang
- Medicine and Biomedical Sciences Graduate Program, University of California at San Diego, La Jolla, California, United States of America
| | - Daniel J. Walsh
- Departments of Biochemistry and Medicine, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, United States of America
| | - Justin R. Barone
- Department of Biological Systems Engineering, Virginia Tech, Blacksburg, Virginia, United States of America
| | - Michael B. Miller
- Departments of Biochemistry and Medicine, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, United States of America
| | - Koren A. Nishina
- Departments of Biochemistry and Medicine, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, United States of America
| | - Sheng Li
- Medicine and Biomedical Sciences Graduate Program, University of California at San Diego, La Jolla, California, United States of America
| | - Surachai Supattapone
- Departments of Biochemistry and Medicine, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, United States of America
- * E-mail:
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Race B, Phillips K, Meade-White K, Striebel J, Chesebro B. Increased infectivity of anchorless mouse scrapie prions in transgenic mice overexpressing human prion protein. J Virol 2015; 89:6022-32. [PMID: 25810548 PMCID: PMC4442444 DOI: 10.1128/jvi.00362-15] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Accepted: 03/18/2015] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED Prion protein (PrP) is found in all mammals, mostly as a glycoprotein anchored to the plasma membrane by a C-terminal glycosylphosphatidylinositol (GPI) linkage. Following prion infection, host protease-sensitive prion protein (PrPsen or PrPC) is converted into an abnormal, disease-associated, protease-resistant form (PrPres). Biochemical characteristics, such as the PrP amino acid sequence, and posttranslational modifications, such as glycosylation and GPI anchoring, can affect the transmissibility of prions as well as the biochemical properties of the PrPres generated. Previous in vivo studies on the effects of GPI anchoring on prion infectivity have not examined cross-species transmission. In this study, we tested the effect of lack of GPI anchoring on a species barrier model using mice expressing human PrP. In this model, anchorless 22L prions derived from tg44 mice were more infectious than 22L prions derived from C57BL/10 mice when tested in tg66 transgenic mice, which expressed wild-type anchored human PrP at 8- to 16-fold above normal. Thus, the lack of the GPI anchor on the PrPres from tg44 mice appeared to reduce the effect of the mouse-human PrP species barrier. In contrast, neither source of prions induced disease in tgRM transgenic mice, which expressed human PrP at 2- to 4-fold above normal. IMPORTANCE Prion protein (PrP) is found in all mammals, usually attached to cells by an anchor molecule called GPI. Following prion infection, PrP is converted into a disease-associated form (PrPres). While most prion diseases are species specific, this finding is not consistent, and species barriers differ in strength. The amino acid sequence of PrP varies among species, and this variability affects prion species barriers. However, other PrP modifications, including glycosylation and GPI anchoring, may also influence cross-species infectivity. We studied the effect of PrP GPI anchoring using a mouse-to-human species barrier model. Experiments showed that prions produced by mice expressing only anchorless PrP were more infectious than prions produced in mice expressing anchored PrP. Thus, the lack of the GPI anchor on prions reduced the effect of the mouse-human species barrier. Our results suggest that prion diseases that produce higher levels of anchorless PrP may pose an increased risk for cross-species infection.
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Affiliation(s)
- Brent Race
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, USA
| | - Katie Phillips
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, USA
| | - Kimberly Meade-White
- Rocky Mountain Veterinary Branch, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, USA
| | - James Striebel
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, USA
| | - Bruce Chesebro
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, USA
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Wenborn A, Terry C, Gros N, Joiner S, D'Castro L, Panico S, Sells J, Cronier S, Linehan JM, Brandner S, Saibil HR, Collinge J, Wadsworth JDF. A novel and rapid method for obtaining high titre intact prion strains from mammalian brain. Sci Rep 2015; 5:10062. [PMID: 25950908 PMCID: PMC4423448 DOI: 10.1038/srep10062] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Accepted: 03/26/2015] [Indexed: 02/02/2023] Open
Abstract
Mammalian prions exist as multiple strains which produce characteristic and highly reproducible phenotypes in defined hosts. How this strain diversity is encoded by a protein-only agent remains one of the most interesting and challenging questions in biology with wide relevance to understanding other diseases involving the aggregation or polymerisation of misfolded host proteins. Progress in understanding mammalian prion strains has however been severely limited by the complexity and variability of the methods used for their isolation from infected tissue and no high resolution structures have yet been reported. Using high-throughput cell-based prion bioassay to re-examine prion purification from first principles we now report the isolation of prion strains to exceptional levels of purity from small quantities of infected brain and demonstrate faithful retention of biological and biochemical strain properties. The method's effectiveness and simplicity should facilitate its wide application and expedite structural studies of prions.
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Affiliation(s)
- Adam Wenborn
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, National Hospital for Neurology and Neurosurgery, Queen Square, London WC1N 3BG, UK
| | - Cassandra Terry
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, National Hospital for Neurology and Neurosurgery, Queen Square, London WC1N 3BG, UK
| | - Nathalie Gros
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, National Hospital for Neurology and Neurosurgery, Queen Square, London WC1N 3BG, UK
| | - Susan Joiner
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, National Hospital for Neurology and Neurosurgery, Queen Square, London WC1N 3BG, UK
| | - Laura D'Castro
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, National Hospital for Neurology and Neurosurgery, Queen Square, London WC1N 3BG, UK
| | - Silvia Panico
- Department of Crystallography and Institute of Structural and Molecular Biology, Birkbeck College, University of London, Malet Street, London WC1E 7HX, UK
| | - Jessica Sells
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, National Hospital for Neurology and Neurosurgery, Queen Square, London WC1N 3BG, UK
| | - Sabrina Cronier
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, National Hospital for Neurology and Neurosurgery, Queen Square, London WC1N 3BG, UK
| | - Jacqueline M Linehan
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, National Hospital for Neurology and Neurosurgery, Queen Square, London WC1N 3BG, UK
| | - Sebastian Brandner
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, National Hospital for Neurology and Neurosurgery, Queen Square, London WC1N 3BG, UK
| | - Helen R Saibil
- Department of Crystallography and Institute of Structural and Molecular Biology, Birkbeck College, University of London, Malet Street, London WC1E 7HX, UK
| | - John Collinge
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, National Hospital for Neurology and Neurosurgery, Queen Square, London WC1N 3BG, UK
| | - Jonathan D F Wadsworth
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, National Hospital for Neurology and Neurosurgery, Queen Square, London WC1N 3BG, UK
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Proteinase K and the structure of PrPSc: The good, the bad and the ugly. Virus Res 2015; 207:120-6. [PMID: 25816779 DOI: 10.1016/j.virusres.2015.03.008] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Revised: 03/14/2015] [Accepted: 03/16/2015] [Indexed: 10/23/2022]
Abstract
Infectious proteins (prions) are, ironically, defined by their resistance to proteolytic digestion. A defining characteristic of the transmissible isoform of the prion protein (PrP(Sc)) is its partial resistance to proteinase K (PK) digestion. Diagnosis of prion disease typically relies upon immunodetection of PK-digested PrP(Sc) by Western blot, ELISA or immunohistochemical detection. PK digestion has also been used to detect differences in prion strains. Thus, PK has been a crucial tool to detect and, thereby, control the spread of prions. PK has also been used as a tool to probe the structure of PrP(Sc). Mass spectrometry and antibodies have been used to identify PK cleavage sites in PrP(Sc). These results have been used to identify the more accessible, flexible stretches connecting the β-strand components in PrP(Sc). These data, combined with physical constraints imposed by spectroscopic results, were used to propose a qualitative model for the structure of PrP(Sc). Assuming that PrP(Sc) is a four rung β-solenoid, we have threaded the PrP sequence to satisfy the PK proteolysis data and other experimental constraints.
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Requena JR, Wille H. The structure of the infectious prion protein: experimental data and molecular models. Prion 2015; 8:60-6. [PMID: 24583975 PMCID: PMC7030906 DOI: 10.4161/pri.28368] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The structures of the infectious prion protein, PrP(Sc), and that of its proteolytically truncated variant, PrP 27-30, have evaded experimental determination due to their insolubility and propensity to aggregate. Molecular modeling has been used to fill this void and to predict their structures, but various modeling approaches have produced significantly different models. The disagreement between the different modeling solutions indicates the limitations of this method. Over the years, in absence of a three-dimensional (3D) structure, a variety of experimental techniques have been used to gain insights into the structure of this biologically, medically, and agriculturally important isoform. Here, we present an overview of experimental results that were published in recent years, and which provided new insights into the molecular architecture of PrP(Sc) and PrP 27-30. Furthermore, we evaluate all published models in light of these recent, experimental data, and come to the conclusion that none of the models can accommodate all of the experimental constraints. Moreover, this conclusion constitutes an open invitation for renewed efforts to model the structure of PrP(Sc).
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