1
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Esmaili M, Eldeeb M. Cellular toxicity of scrapie prions in prion diseases; a biochemical and molecular overview. Mol Biol Rep 2023; 50:1743-1752. [PMID: 36446981 DOI: 10.1007/s11033-022-07806-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Revised: 07/15/2022] [Accepted: 07/19/2022] [Indexed: 12/03/2022]
Abstract
Transmissible spongiform encephalopathies (TSEs) or prion diseases consist of a broad range of fatal neurological disorders affecting humans and animals. Contrary to Watson and Crick's 'central dogma', prion diseases are caused by a protein, devoid of DNA involvement. Herein, we briefly review various cellular and biological aspects of prions and prion pathogenesis focusing mainly on historical milestones, biosynthesis, degradation, structure-function of cellular and scrapie forms of prions .
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Affiliation(s)
- Mansoore Esmaili
- Department of Biochemistry, University of Alberta, Edmonton, AB, Canada.
| | - Mohamed Eldeeb
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, Canada.
- Department of Chemistry, Faculty of Science, Cairo University, Giza, Egypt.
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2
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Alves Conceição C, Assis de Lemos G, Barros CA, Vieira TCRG. What is the role of lipids in prion conversion and disease? Front Mol Neurosci 2023; 15:1032541. [PMID: 36704327 PMCID: PMC9871914 DOI: 10.3389/fnmol.2022.1032541] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Accepted: 12/19/2022] [Indexed: 01/12/2023] Open
Abstract
The molecular cause of transmissible spongiform encephalopathies (TSEs) involves the conversion of the cellular prion protein (PrPC) into its pathogenic form, called prion scrapie (PrPSc), which is prone to the formation of amorphous and amyloid aggregates found in TSE patients. Although the mechanisms of conversion of PrPC into PrPSc are not entirely understood, two key points are currently accepted: (i) PrPSc acts as a seed for the recruitment of native PrPC, inducing the latter's conversion to PrPSc; and (ii) other biomolecules, such as DNA, RNA, or lipids, can act as cofactors, mediating the conversion from PrPC to PrPSc. Interestingly, PrPC is anchored by a glycosylphosphatidylinositol molecule in the outer cell membrane. Therefore, interactions with lipid membranes or alterations in the membranes themselves have been widely investigated as possible factors for conversion. Alone or in combination with RNA molecules, lipids can induce the formation of PrP in vitro-produced aggregates capable of infecting animal models. Here, we discuss the role of lipids in prion conversion and infectivity, highlighting the structural and cytotoxic aspects of lipid-prion interactions. Strikingly, disorders like Alzheimer's and Parkinson's disease also seem to be caused by changes in protein structure and share pathogenic mechanisms with TSEs. Thus, we posit that comprehending the process of PrP conversion is relevant to understanding critical events involved in a variety of neurodegenerative disorders and will contribute to developing future therapeutic strategies for these devastating conditions.
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Affiliation(s)
- Cyntia Alves Conceição
- Institute of Medical Biochemistry Leopoldo de Meis, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil,National Institute of Science and Technology for Structural Biology and Bioimaging, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Gabriela Assis de Lemos
- Institute of Medical Biochemistry Leopoldo de Meis, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil,National Institute of Science and Technology for Structural Biology and Bioimaging, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Caroline Augusto Barros
- Institute of Medical Biochemistry Leopoldo de Meis, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil,National Institute of Science and Technology for Structural Biology and Bioimaging, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Tuane C. R. G. Vieira
- Institute of Medical Biochemistry Leopoldo de Meis, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil,National Institute of Science and Technology for Structural Biology and Bioimaging, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil,*Correspondence: Tuane C. R. G. Vieira, ✉
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3
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Wang LJ, Gu XD, Li XX, Shen L, Ji HF. Comparative analysis of heparin affecting the biochemical properties of chicken and murine prion proteins. PLoS One 2021; 16:e0247248. [PMID: 33600459 PMCID: PMC7891698 DOI: 10.1371/journal.pone.0247248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2020] [Accepted: 02/03/2021] [Indexed: 11/19/2022] Open
Abstract
The conversion of cellular prion protein (PrPC) to disease-provoking conformer (PrPSc) is crucial in the pathogenesis of prion diseases. Heparin has been shown to enhance mammalian prion protein misfolding. As spontaneous prion disease has not been reported in non-mammalian species, such as chicken, it is interesting to explore the influence of heparin on the conversion of chicken prion protein (ChPrP). Herein, we investigated the influences of heparin on biochemical properties of full-length recombinant ChPrP, with murine prion protein (MoPrP) as control. The results showed that at low heparin concentration (10 μg/mL), a great loss of solubility was observed for both MoPrP and ChPrP using solubility assays. In contrast, when the concentration of heparin was high (30 μg/mL), the solubility of MoPrP and ChPrP both decreased slightly. Using circular dichroism, PK digestion and transmission electron microscopy, significantly increased β-sheet content, PK resistance and size of aggregates were observed for MoPrP interacted with 30 μg/mL heparin, whereas 30 μg/mL heparin-treated ChPrP showed less PK resistance and slight increase of β-sheet structure. Therefore, heparin can induce conformational changes in both MoPrP and ChPrP and the biochemical properties of the aggregates induced by heparin could be modified by heparin concentration. These results highlight the importance of concentration of cofactors affecting PrP misfolding.
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Affiliation(s)
- Li-Juan Wang
- Institute of Biomedical Research, Shandong University of Technology, Zibo, Shandong, People’s Republic of China
- Shandong Provincial Research Center for Bioinformatic Engineering and Technique, Zibo Key Laboratory of New Drug Development of Neurodegenerative Diseases, School of Life Sciences, Shandong University of Technology, Zibo, Shandong, People’s Republic of China
- * E-mail: (LJW); (LS); (HFJ)
| | - Xiao-Dan Gu
- Institute of Biomedical Research, Shandong University of Technology, Zibo, Shandong, People’s Republic of China
- Shandong Provincial Research Center for Bioinformatic Engineering and Technique, Zibo Key Laboratory of New Drug Development of Neurodegenerative Diseases, School of Life Sciences, Shandong University of Technology, Zibo, Shandong, People’s Republic of China
| | - Xiao-Xiao Li
- Institute of Biomedical Research, Shandong University of Technology, Zibo, Shandong, People’s Republic of China
- Shandong Provincial Research Center for Bioinformatic Engineering and Technique, Zibo Key Laboratory of New Drug Development of Neurodegenerative Diseases, School of Life Sciences, Shandong University of Technology, Zibo, Shandong, People’s Republic of China
| | - Liang Shen
- Institute of Biomedical Research, Shandong University of Technology, Zibo, Shandong, People’s Republic of China
- Shandong Provincial Research Center for Bioinformatic Engineering and Technique, Zibo Key Laboratory of New Drug Development of Neurodegenerative Diseases, School of Life Sciences, Shandong University of Technology, Zibo, Shandong, People’s Republic of China
- * E-mail: (LJW); (LS); (HFJ)
| | - Hong-Fang Ji
- Institute of Biomedical Research, Shandong University of Technology, Zibo, Shandong, People’s Republic of China
- Shandong Provincial Research Center for Bioinformatic Engineering and Technique, Zibo Key Laboratory of New Drug Development of Neurodegenerative Diseases, School of Life Sciences, Shandong University of Technology, Zibo, Shandong, People’s Republic of China
- * E-mail: (LJW); (LS); (HFJ)
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Kostylev MA, Tuttle MD, Lee S, Klein LE, Takahashi H, Cox TO, Gunther EC, Zilm KW, Strittmatter SM. Liquid and Hydrogel Phases of PrP C Linked to Conformation Shifts and Triggered by Alzheimer's Amyloid-β Oligomers. Mol Cell 2018; 72:426-443.e12. [PMID: 30401430 DOI: 10.1016/j.molcel.2018.10.009] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Revised: 08/08/2018] [Accepted: 10/04/2018] [Indexed: 12/14/2022]
Abstract
Protein phase separation by low-complexity, intrinsically disordered domains generates membraneless organelles and links to neurodegeneration. Cellular prion protein (PrPC) contains such domains, causes spongiform degeneration, and is a receptor for Alzheimer's amyloid-β oligomers (Aβo). Here, we show that PrPC separates as a liquid phase, in which α-helical Thr become unfolded. At the cell surface, PrPC Lys residues interact with Aβo to create a hydrogel containing immobile Aβo and relatively mobile PrPC. The Aβo/PrP hydrogel has a well-defined stoichiometry and dissociates with excess Aβo. NMR studies of hydrogel PrPC reveal a distinct α-helical conformation for natively unfolded amino-terminal Gly and Ala residues. Aβo/PrP hydrogel traps signal-transducing mGluR5 on the plasma membrane. Recombinant PrPC extracts endogenous Aβo from human Alzheimer's soluble brain lysates into hydrogel, and a PrPC antagonist releases Aβo from endogenous brain hydrogel. Thus, coupled phase and conformational transitions of PrPC are driven by Aβ species from Alzheimer's disease.
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Affiliation(s)
- Mikhail A Kostylev
- Cellular Neuroscience, Neurodegeneration and Repair Program, Departments of Neurology and Neuroscience, Yale University School of Medicine, New Haven, CT, USA
| | - Marcus D Tuttle
- Cellular Neuroscience, Neurodegeneration and Repair Program, Departments of Neurology and Neuroscience, Yale University School of Medicine, New Haven, CT, USA; Department of Chemistry, Yale University School of Medicine, New Haven, CT, USA
| | - Suho Lee
- Cellular Neuroscience, Neurodegeneration and Repair Program, Departments of Neurology and Neuroscience, Yale University School of Medicine, New Haven, CT, USA
| | - Lauren E Klein
- Department of Chemistry, Yale University School of Medicine, New Haven, CT, USA
| | - Hideyuki Takahashi
- Cellular Neuroscience, Neurodegeneration and Repair Program, Departments of Neurology and Neuroscience, Yale University School of Medicine, New Haven, CT, USA
| | - Timothy O Cox
- Cellular Neuroscience, Neurodegeneration and Repair Program, Departments of Neurology and Neuroscience, Yale University School of Medicine, New Haven, CT, USA
| | - Erik C Gunther
- Cellular Neuroscience, Neurodegeneration and Repair Program, Departments of Neurology and Neuroscience, Yale University School of Medicine, New Haven, CT, USA
| | - Kurt W Zilm
- Department of Chemistry, Yale University School of Medicine, New Haven, CT, USA.
| | - Stephen M Strittmatter
- Cellular Neuroscience, Neurodegeneration and Repair Program, Departments of Neurology and Neuroscience, Yale University School of Medicine, New Haven, CT, USA.
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Katorcha E, Gonzalez-Montalban N, Makarava N, Kovacs GG, Baskakov IV. Prion replication environment defines the fate of prion strain adaptation. PLoS Pathog 2018; 14:e1007093. [PMID: 29928047 PMCID: PMC6013019 DOI: 10.1371/journal.ppat.1007093] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Accepted: 05/14/2018] [Indexed: 11/18/2022] Open
Abstract
The main risk of emergence of prion diseases in humans is associated with a cross-species transmission of prions of zoonotic origin. Prion transmission between species is regulated by a species barrier. Successful cross-species transmission is often accompanied by strain adaptation and result in stable changes of strain-specific disease phenotype. Amino acid sequences of host PrPC and donor PrPSc as well as strain-specific structure of PrPSc are believed to be the main factors that control species barrier and strain adaptation. Yet, despite our knowledge of the primary structures of mammalian prions, predicting the fate of prion strain adaptation is very difficult if possible at all. The current study asked the question whether changes in cofactor environment affect the fate of prions adaptation. To address this question, hamster strain 263K was propagated under normal or RNA-depleted conditions using serial Protein Misfolding Cyclic Amplification (PMCA) conducted first in mouse and then hamster substrates. We found that 263K propagated under normal conditions in mouse and then hamster substrates induced the disease phenotype similar to the original 263K. Surprisingly, 263K that propagated first in RNA-depleted mouse substrate and then normal hamster substrate produced a new disease phenotype upon serial transmission. Moreover, 263K that propagated in RNA-depleted mouse and then RNA-depleted hamster substrates failed to induce clinical diseases for three serial passages despite a gradual increase of PrPSc in animals. To summarize, depletion of RNA in prion replication reactions changed the rate of strain adaptation and the disease phenotype upon subsequent serial passaging of PMCA-derived materials in animals. The current studies suggest that replication environment plays an important role in determining the fate of prion strain adaptation. The main risk of emergence of prion diseases in humans is associated with a cross-species transmission of prions of zoonotic origin. Prion transmission between species is regulated by a species barrier. Amino acid sequences of host prion protein and donor prions are believed to be the main factors that control species barrier and strain adaptation. Yet, despite our knowledge of the primary structures of mammalian prions, predicting the fate of prion strain adaptation is very difficult. The current study asked the question whether changes in cofactor environment affect the fate of prions adaptation. To address this question, hamster prion strain was propagated under normal or RNA-depleted conditions in vitro first using mouse and then hamster substrates. This work demonstrated that depletion of RNA in prion replication reactions changed the rate of strain adaptation and the disease phenotype upon subsequent serial passaging in animals. The current studies suggest that replication environment plays an important role in determining the fate of prion strain adaptation.
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Affiliation(s)
- Elizaveta Katorcha
- Center for Biomedical Engineering and Technology, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Nuria Gonzalez-Montalban
- Center for Biomedical Engineering and Technology, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Natallia Makarava
- Center for Biomedical Engineering and Technology, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Gabor G. Kovacs
- Institute of Neurology, Medical University of Vienna, Vienna, Austria
| | - Ilia V. Baskakov
- Center for Biomedical Engineering and Technology, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
- * E-mail:
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6
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Alred EJ, Lodangco I, Gallaher J, Hansmann UH. Mutations Alter RNA-Mediated Conversion of Human Prions. ACS OMEGA 2018; 3:3936-3944. [PMID: 29732450 PMCID: PMC5928492 DOI: 10.1021/acsomega.7b02007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/17/2017] [Accepted: 03/28/2018] [Indexed: 06/08/2023]
Abstract
Prion diseases are connected with self-replication and self-propagation of misfolded proteins. The rate-limiting factor is the formation of the initial seed. We have recently studied the early stages in the conversion between functional PrPC and the infectious scrapie PrPSC form, triggered by the binding of RNA. Here, we study how this process is modulated by the prion sequence. We focus on residues 129 and 178, which are connected to the hereditary neurodegenerative disease fatal familial insomnia.
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7
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Ladner-Keay CL, LeVatte M, Wishart DS. Role of polysaccharide and lipid in lipopolysaccharide induced prion protein conversion. Prion 2017; 10:466-483. [PMID: 27906600 PMCID: PMC5161299 DOI: 10.1080/19336896.2016.1254857] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Conversion of native cellular prion protein (PrPc) from an α-helical structure to a toxic and infectious β-sheet structure (PrPSc) is a critical step in the development of prion disease. There are some indications that the formation of PrPSc is preceded by a β-sheet rich PrP (PrPβ) form which is non-infectious, but is an intermediate in the formation of infectious PrPSc. Furthermore the presence of lipid cofactors is thought to be critical in the formation of both intermediate-PrPβ and lethal, infectious PrPSc. We previously discovered that the endotoxin, lipopolysaccharide (LPS), interacts with recombinant PrPc and induces rapid conformational change to a β-sheet rich structure. This LPS induced PrPβ structure exhibits PrPSc-like features including proteinase K (PK) resistance and the capacity to form large oligomers and rod-like fibrils. LPS is a large, complex molecule with lipid, polysaccharide, 2-keto-3-deoxyoctonate (Kdo) and glucosamine components. To learn more about which LPS chemical constituents are critical for binding PrPc and inducing β-sheet conversion we systematically investigated which chemical components of LPS either bind or induce PrP conversion to PrPβ. We analyzed this PrP conversion using resolution enhanced native acidic gel electrophoresis (RENAGE), tryptophan fluorescence, circular dichroism, electron microscopy and PK resistance. Our results indicate that a minimal version of LPS (called detoxified and partially de-acylated LPS or dLPS) containing a portion of the polysaccharide and a portion of the lipid component is sufficient for PrP conversion. Lipid components, alone, and saccharide components, alone, are insufficient for conversion.
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Affiliation(s)
- Carol L Ladner-Keay
- a Department of Biological Sciences , University of Alberta , Edmonton , Alberta , Canada
| | - Marcia LeVatte
- a Department of Biological Sciences , University of Alberta , Edmonton , Alberta , Canada
| | - David S Wishart
- a Department of Biological Sciences , University of Alberta , Edmonton , Alberta , Canada.,b Department of Computing Science , University of Alberta , Edmonton , Alberta , Canada
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8
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Miyazawa K, Masujin K, Okada H, Ushiki-Kaku Y, Matsuura Y, Yokoyama T. Selective propagation of mouse-passaged scrapie prions with long incubation period from a mixed prion population using GT1-7 cells. PLoS One 2017. [PMID: 28636656 PMCID: PMC5479544 DOI: 10.1371/journal.pone.0179317] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In our previous study, we demonstrated the propagation of mouse-passaged scrapie isolates with long incubation periods (L-type) derived from natural Japanese sheep scrapie cases in murine hypothalamic GT1-7 cells, along with disease-associated prion protein (PrPSc) accumulation. We here analyzed the susceptibility of GT1-7 cells to scrapie prions by exposure to infected mouse brains at different passages, following interspecies transmission. Wild-type mice challenged with a natural sheep scrapie case (Kanagawa) exhibited heterogeneity of transmitted scrapie prions in early passages, and this mixed population converged upon one with a short incubation period (S-type) following subsequent passages. However, when GT1-7 cells were challenged with these heterologous samples, L-type prions became dominant. This study demonstrated that the susceptibility of GT1-7 cells to L-type prions was at least 105 times higher than that to S-type prions and that L-type prion-specific biological characteristics remained unchanged after serial passages in GT1-7 cells. This suggests that a GT1-7 cell culture model would be more useful for the economical and stable amplification of L-type prions at the laboratory level. Furthermore, this cell culture model might be used to selectively propagate L-type scrapie prions from a mixed prion population.
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Affiliation(s)
- Kohtaro Miyazawa
- Prion Diseases Unit, Division of Transboundary Animal Disease, National Institute of Animal Health, National Agriculture and Food Research Organization (NARO), Tsukuba, Ibaraki, Japan
- * E-mail:
| | - Kentaro Masujin
- Prion Diseases Unit, Division of Transboundary Animal Disease, National Institute of Animal Health, National Agriculture and Food Research Organization (NARO), Tsukuba, Ibaraki, Japan
| | - Hiroyuki Okada
- Prion Diseases Unit, Division of Transboundary Animal Disease, National Institute of Animal Health, National Agriculture and Food Research Organization (NARO), Tsukuba, Ibaraki, Japan
| | | | - Yuichi Matsuura
- Prion Diseases Unit, Division of Transboundary Animal Disease, National Institute of Animal Health, National Agriculture and Food Research Organization (NARO), Tsukuba, Ibaraki, Japan
| | - Takashi Yokoyama
- Department of Planning and General Administration, National Institute of Animal Health, NARO, Tsukuba, Ibaraki, Japan
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9
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Alred EJ, Nguyen M, Martin M, Hansmann UHE. Molecular dynamics simulations of early steps in RNA-mediated conversion of prions. Protein Sci 2017; 26:1524-1534. [PMID: 28425641 DOI: 10.1002/pro.3178] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Accepted: 04/16/2017] [Indexed: 01/23/2023]
Abstract
The rate-limiting step in prion diseases is the initial transition of a prion protein from its native form into a mis-folded state in which the protein not only forms cell-toxic aggregates but also becomes infectious. Recent experiments implicate polyadenosine RNA as a possible agent for generating the initial seed. In order to understand the mechanism of RNA-mediated mis-folding and aggregation of prions, we dock polyadenosine RNA to mouse and human prion models. Changes in stability and secondary structure of the prions upon binding to polyadenosine RNA are evaluated by comparing molecular dynamics simulations of these complexes with that of the unbound prions.
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Affiliation(s)
- Erik J Alred
- Chemistry and Biochemistry, University of Oklahoma, Norman, Oklahoma
| | - Michael Nguyen
- Chemistry and Biochemistry, University of Oklahoma, Norman, Oklahoma
| | - Maggie Martin
- Chemistry and Biochemistry, University of Oklahoma, Norman, Oklahoma
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10
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Martínez J, Sánchez R, Castellanos M, Makarava N, Aguzzi A, Baskakov IV, Gasset M. PrP charge structure encodes interdomain interactions. Sci Rep 2015; 5:13623. [PMID: 26323476 PMCID: PMC4555102 DOI: 10.1038/srep13623] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Accepted: 07/31/2015] [Indexed: 11/19/2022] Open
Abstract
Almost all proteins contain charged residues, and their chain distribution is tailored to fulfill essential ionic interactions for folding, binding and catalysis. Among proteins, the hinged two-domain chain of the cellular prion protein (PrPC) exhibits a peculiar charge structure with unclear consequences in its structural malleability. To decipher the charge design role, we generated charge-reverted mutants for each domain and analyzed their effect on conformational and metabolic features. We found that charges contain the information for interdomain interactions. Use of dynamic light scattering and thermal denaturation experiments delineates the compaction of the α-fold by an electrostatic compensation between the polybasic 23–30 region and the α3 electronegative surface. This interaction increases stability and disfavors fibrillation. Independently of this structural effect, the N-terminal electropositive clusters regulate the α-cleavage efficiency. In the fibrillar state, use of circular dichroism, atomic-force and fluorescence microscopies reveal that the N-terminal positive clusters and the α3 electronegative surface dictate the secondary structure, the assembly hierarchy and the growth length of the fibril state. These findings show that the PrP charge structure functions as a code set up to ensure function and reduce pathogenic routes.
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Affiliation(s)
- Javier Martínez
- Instituto Química-Física "Rocasolano", Consejo Superior de Investigaciones Científicas, Madrid 28006, Spain
| | - Rosa Sánchez
- Instituto Química-Física "Rocasolano", Consejo Superior de Investigaciones Científicas, Madrid 28006, Spain
| | - Milagros Castellanos
- Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, Madrid, Spain; IMDEA-Nanociencia, Madrid 28049, Spain
| | - Natallia Makarava
- Center for Biomedical Engineering and Technology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Adriano Aguzzi
- Institute of Neuropathology, University Hospital of Zürich, Zürich 8091, Switzerland
| | - Ilia V Baskakov
- Center for Biomedical Engineering and Technology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - María Gasset
- Instituto Química-Física "Rocasolano", Consejo Superior de Investigaciones Científicas, Madrid 28006, Spain
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11
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Contrasting Effects of Two Lipid Cofactors of Prion Replication on the Conformation of the Prion Protein. PLoS One 2015; 10:e0130283. [PMID: 26090881 PMCID: PMC4474664 DOI: 10.1371/journal.pone.0130283] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Accepted: 05/18/2015] [Indexed: 01/03/2023] Open
Abstract
Recent studies introduced two experimental protocols for converting full-length recombinant prion protein (rPrP) purified from E.coli into the infectious prion state (PrPSc) with high infectivity titers. Both protocols employed protein misfolding cyclic amplification (PMCA) for generating PrPScde novo, but used two different lipids, 1-palmitoyl-2-oleolyl-sn-glycero-3-phospho(1’-rac-glycerol) (POPG) or phosphatidylethanolamine (PE), as conversion cofactors. The current study compares the effect of POPG and PE on the physical properties of native, α-helical full-length mouse rPrP under the solvent conditions used for converting rPrP into PrPSc. Surprisingly, the effects of POPG and PE on rPrP physical properties, including its conformation, thermodynamic stability, aggregation state and interaction with a lipid, were found to be remarkably different. PE was shown to have minimal, if any, effects on rPrP thermodynamic stability, cooperativity of unfolding, immediate solvent environment or aggregation state. In fact, little evidence indicates that PE interacts with rPrP directly. In contrast, POPG was found to bind to and induce dramatic changes in rPrP structure, including a loss of α-helical conformation and formation of large lipid-protein aggregates that were resistant to partially denaturing conditions. These results suggest that the mechanisms by which lipids assist conversion of rPrP into PrPSc might be fundamentally different for POPG and PE.
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12
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Le Brun AP, Haigh CL, Drew SC, James M, Boland MP, Collins SJ. Neutron reflectometry studies define prion protein N-terminal peptide membrane binding. Biophys J 2014; 107:2313-24. [PMID: 25418300 PMCID: PMC4241452 DOI: 10.1016/j.bpj.2014.09.027] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2014] [Revised: 09/08/2014] [Accepted: 09/19/2014] [Indexed: 10/24/2022] Open
Abstract
The prion protein (PrP), widely recognized to misfold into the causative agent of the transmissible spongiform encephalopathies, has previously been shown to bind to lipid membranes with binding influenced by both membrane composition and pH. Aside from the misfolding events associated with prion pathogenesis, PrP can undergo various posttranslational modifications, including internal cleavage events. Alpha- and beta-cleavage of PrP produces two N-terminal fragments, N1 and N2, respectively, which interact specifically with negatively charged phospholipids at low pH. Our previous work probing N1 and N2 interactions with supported bilayers raised the possibility that the peptides could insert deeply with minimal disruption. In the current study we aimed to refine the binding parameters of these peptides with lipid bilayers. To this end, we used neutron reflectometry to define the structural details of this interaction in combination with quartz crystal microbalance interrogation. Neutron reflectometry confirmed that peptides equivalent to N1 and N2 insert into the interstitial space between the phospholipid headgroups but do not penetrate into the acyl tail region. In accord with our previous studies, interaction was stronger for the N1 fragment than for the N2, with more peptide bound per lipid. Neutron reflectometry analysis also detected lengthening of the lipid acyl tails, with a concurrent decrease in lipid area. This was most evident for the N1 peptide and suggests an induction of increased lipid order in the absence of phase transition. These observations stand in clear contrast to the findings of analogous studies of Ab and ?-synuclein and thereby support the possibility of a functional role for such N-terminal fragment-membrane interactions.
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Affiliation(s)
- Anton P Le Brun
- Bragg Institute, Australian Nuclear Science and Technology Organisation, New Illawarra Road, Lucas Heights, New South Wales, 2234, Australia
| | - Cathryn L Haigh
- Department of Pathology, Kenneth Myer Building, The University of Melbourne, Victoria, 3010, Australia
| | - Simon C Drew
- Florey Department of Neuroscience and Mental Health, The University of Melbourne, Victoria, 3010, Australia
| | - Michael James
- Bragg Institute, Australian Nuclear Science and Technology Organisation, New Illawarra Road, Lucas Heights, New South Wales, 2234, Australia; School of Chemistry, University of New South Wales, Kensington, New South Wales, 2052, Australia
| | - Martin P Boland
- Department of Pathology, Kenneth Myer Building, The University of Melbourne, Victoria, 3010, Australia
| | - Steven J Collins
- Department of Pathology, Kenneth Myer Building, The University of Melbourne, Victoria, 3010, Australia.
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