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Masone A, Zucchelli C, Caruso E, Lavigna G, Eraña H, Giachin G, Tapella L, Comerio L, Restelli E, Raimondi I, Elezgarai SR, De Leo F, Quilici G, Taiarol L, Oldrati M, Lorenzo NL, García-Martínez S, Cagnotto A, Lucchetti J, Gobbi M, Vanni I, Nonno R, Di Bari MA, Tully MD, Cecatiello V, Ciossani G, Pasqualato S, Van Anken E, Salmona M, Castilla J, Requena JR, Banfi S, Musco G, Chiesa R. A tetracationic porphyrin with dual anti-prion activity. iScience 2023; 26:107480. [PMID: 37636075 PMCID: PMC10448035 DOI: 10.1016/j.isci.2023.107480] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 08/09/2022] [Accepted: 07/24/2023] [Indexed: 08/29/2023] Open
Abstract
Prions are deadly infectious agents made of PrPSc, a misfolded variant of the cellular prion protein (PrPC) which self-propagates by inducing misfolding of native PrPC. PrPSc can adopt different pathogenic conformations (prion strains), which can be resistant to potential drugs, or acquire drug resistance, hampering the development of effective therapies. We identified Zn(II)-BnPyP, a tetracationic porphyrin that binds to distinct domains of native PrPC, eliciting a dual anti-prion effect. Zn(II)-BnPyP binding to a C-terminal pocket destabilizes the native PrPC fold, hindering conversion to PrPSc; Zn(II)-BnPyP binding to the flexible N-terminal tail disrupts N- to C-terminal interactions, triggering PrPC endocytosis and lysosomal degradation, thus reducing the substrate for PrPSc generation. Zn(II)-BnPyP inhibits propagation of different prion strains in vitro, in neuronal cells and organotypic brain cultures. These results identify a PrPC-targeting compound with an unprecedented dual mechanism of action which might be exploited to achieve anti-prion effects without engendering drug resistance.
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Affiliation(s)
- Antonio Masone
- Laboratory of Prion Neurobiology, Department of Neuroscience, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, 20156 Milan, Italy
| | - Chiara Zucchelli
- Biomolecular NMR Unit, Division of Genetics and Cell Biology, IRCCS Ospedale San Raffaele, 20132 Milan, Italy
| | - Enrico Caruso
- Department of Biotechnology and Life Sciences, University of Insubria, 21100 Varese, Italy
| | - Giada Lavigna
- Laboratory of Prion Neurobiology, Department of Neuroscience, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, 20156 Milan, Italy
| | - Hasier Eraña
- Centro de Investigación Cooperativa en Biociencias (CIC BioGUNE), Basque Research and Technology Alliance (BRTA), 48160 Derio, Bizkaia, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Infecciosas (CIBERINFEC), Carlos III National Health Institute, 28029 Madrid, Spain
| | - Gabriele Giachin
- Department of Chemical Sciences (DiSC), University of Padua, 35131 Padua, Italy
| | - Laura Tapella
- Laboratory of Prion Neurobiology, Department of Neuroscience, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, 20156 Milan, Italy
| | - Liliana Comerio
- Laboratory of Prion Neurobiology, Department of Neuroscience, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, 20156 Milan, Italy
| | - Elena Restelli
- Laboratory of Prion Neurobiology, Department of Neuroscience, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, 20156 Milan, Italy
| | - Ilaria Raimondi
- Laboratory of Prion Neurobiology, Department of Neuroscience, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, 20156 Milan, Italy
| | - Saioa R. Elezgarai
- Laboratory of Prion Neurobiology, Department of Neuroscience, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, 20156 Milan, Italy
| | - Federica De Leo
- Biomolecular NMR Unit, Division of Genetics and Cell Biology, IRCCS Ospedale San Raffaele, 20132 Milan, Italy
| | - Giacomo Quilici
- Biomolecular NMR Unit, Division of Genetics and Cell Biology, IRCCS Ospedale San Raffaele, 20132 Milan, Italy
| | - Lorenzo Taiarol
- Laboratory of Prion Neurobiology, Department of Neuroscience, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, 20156 Milan, Italy
| | - Marvin Oldrati
- Laboratory of Prion Neurobiology, Department of Neuroscience, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, 20156 Milan, Italy
| | - Nuria L. Lorenzo
- CIMUS Biomedical Research Institute and Department of Medical Sciences, University of Santiago de Compostela-IDIS, 15782 Santiago de Compostela, Spain
| | - Sandra García-Martínez
- Centro de Investigación Cooperativa en Biociencias (CIC BioGUNE), Basque Research and Technology Alliance (BRTA), 48160 Derio, Bizkaia, Spain
| | - Alfredo Cagnotto
- Laboratory of Biochemistry and Protein Chemistry, Department of Molecular Biochemistry and Pharmacology, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, 20156 Milan, Italy
| | - Jacopo Lucchetti
- Laboratory of Pharmacodynamics and Pharmacokinetics, Department of Molecular Biochemistry and Pharmacology, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, 20156 Milan, Italy
| | - Marco Gobbi
- Laboratory of Pharmacodynamics and Pharmacokinetics, Department of Molecular Biochemistry and Pharmacology, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, 20156 Milan, Italy
| | - Ilaria Vanni
- Department of Food Safety, Nutrition and Veterinary Public Health, Istituto Superiore di Sanità, 00161 Rome, Italy
| | - Romolo Nonno
- Department of Food Safety, Nutrition and Veterinary Public Health, Istituto Superiore di Sanità, 00161 Rome, Italy
| | - Michele A. Di Bari
- Department of Food Safety, Nutrition and Veterinary Public Health, Istituto Superiore di Sanità, 00161 Rome, Italy
| | - Mark D. Tully
- Structural Biology Group, European Synchrotron Radiation Facility (ESRF), 38000 Grenoble, France
| | - Valentina Cecatiello
- Department of Experimental Oncology, European Institute of Oncology (IEO) IRCCS, 20141 Milan, Italy
| | - Giuseppe Ciossani
- Department of Experimental Oncology, European Institute of Oncology (IEO) IRCCS, 20141 Milan, Italy
| | - Sebastiano Pasqualato
- Department of Experimental Oncology, European Institute of Oncology (IEO) IRCCS, 20141 Milan, Italy
| | - Eelco Van Anken
- Protein Transport and Secretion Unit, Division of Genetics and Cell Biology, IRCCS Ospedale San Raffaele, 20132 Milan, Italy
| | - Mario Salmona
- Laboratory of Biochemistry and Protein Chemistry, Department of Molecular Biochemistry and Pharmacology, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, 20156 Milan, Italy
| | - Joaquín Castilla
- Centro de Investigación Cooperativa en Biociencias (CIC BioGUNE), Basque Research and Technology Alliance (BRTA), 48160 Derio, Bizkaia, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Infecciosas (CIBERINFEC), Carlos III National Health Institute, 28029 Madrid, Spain
- IKERBASQUE, Basque Foundation for Science, 48009 Bilbao, Bizkaia, Spain
| | - Jesús R. Requena
- CIMUS Biomedical Research Institute and Department of Medical Sciences, University of Santiago de Compostela-IDIS, 15782 Santiago de Compostela, Spain
| | - Stefano Banfi
- Department of Biotechnology and Life Sciences, University of Insubria, 21100 Varese, Italy
| | - Giovanna Musco
- Biomolecular NMR Unit, Division of Genetics and Cell Biology, IRCCS Ospedale San Raffaele, 20132 Milan, Italy
| | - Roberto Chiesa
- Laboratory of Prion Neurobiology, Department of Neuroscience, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, 20156 Milan, Italy
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Whitfield JF, Rennie K, Chakravarthy B. Alzheimer's Disease and Its Possible Evolutionary Origin: Hypothesis. Cells 2023; 12:1618. [PMID: 37371088 PMCID: PMC10297544 DOI: 10.3390/cells12121618] [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: 04/01/2023] [Revised: 05/29/2023] [Accepted: 06/08/2023] [Indexed: 06/29/2023] Open
Abstract
The enormous, 2-3-million-year evolutionary expansion of hominin neocortices to the current enormity enabled humans to take over the planet. However, there appears to have been a glitch, and it occurred without a compensatory expansion of the entorhinal cortical (EC) gateway to the hippocampal memory-encoding system needed to manage the processing of the increasing volume of neocortical data converging on it. The resulting age-dependent connectopathic glitch was unnoticed by the early short-lived populations. It has now surfaced as Alzheimer's disease (AD) in today's long-lived populations. With advancing age, processing of the converging neocortical data by the neurons of the relatively small lateral entorhinal cortex (LEC) inflicts persistent strain and high energy costs on these cells. This may result in their hyper-release of harmless Aβ1-42 monomers into the interstitial fluid, where they seed the formation of toxic amyloid-β oligomers (AβOs) that initiate AD. At the core of connectopathic AD are the postsynaptic cellular prion protein (PrPC). Electrostatic binding of the negatively charged AβOs to the positively charged N-terminus of PrPC induces hyperphosphorylation of tau that destroys synapses. The spread of these accumulating AβOs from ground zero is supported by Aβ's own production mediated by target cells' Ca2+-sensing receptors (CaSRs). These data suggest that an early administration of a strongly positively charged, AβOs-interacting peptide or protein, plus an inhibitor of CaSR, might be an effective AD-arresting therapeutic combination.
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Affiliation(s)
- James F. Whitfield
- Human Health Therapeutics, National Research Council, Ottawa, ON K1A 0R6, Canada
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Gielnik M, Szymańska A, Dong X, Jarvet J, Svedružić ŽM, Gräslund A, Kozak M, Wärmländer SKTS. Prion Protein Octarepeat Domain Forms Transient β-Sheet Structures upon Residue-Specific Binding to Cu(II) and Zn(II) Ions. Biochemistry 2023. [PMID: 37163663 DOI: 10.1021/acs.biochem.3c00129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Misfolding of the cellular prion protein (PrPC) is associated with the development of fatal neurodegenerative diseases called transmissible spongiform encephalopathies (TSEs). Metal ions appear to play a crucial role in PrPC misfolding. PrPC is a combined Cu(II) and Zn(II) metal-binding protein, where the main metal-binding site is located in the octarepeat (OR) region. Thus, the biological function of PrPC may involve the transport of divalent metal ions across membranes or buffering concentrations of divalent metal ions in the synaptic cleft. Recent studies have shown that an excess of Cu(II) ions can result in PrPC instability, oligomerization, and/or neuroinflammation. Here, we have used biophysical methods to characterize Cu(II) and Zn(II) binding to the isolated OR region of PrPC. Circular dichroism (CD) spectroscopy data suggest that the OR domain binds up to four Cu(II) ions or two Zn(II) ions. Binding of the first metal ion results in a structural transition from the polyproline II helix to the β-turn structure, while the binding of additional metal ions induces the formation of β-sheet structures. Fluorescence spectroscopy data indicate that the OR region can bind both Cu(II) and Zn(II) ions at neutral pH, but under acidic conditions, it binds only Cu(II) ions. Molecular dynamics simulations suggest that binding of either metal ion to the OR region results in the formation of β-hairpin structures. As the formation of β-sheet structures can be a first step toward amyloid formation, we propose that high concentrations of either Cu(II) or Zn(II) ions may have a pro-amyloid effect in TSE diseases.
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Affiliation(s)
- Maciej Gielnik
- Department of Macromolecular Physics, Faculty of Physics, Adam Mickiewicz University, PL 61-614 Poznań, Poland
| | - Aneta Szymańska
- Department of Biomedical Chemistry, Faculty of Chemistry, Gdańsk University, PL 80-308 Gdańsk, Poland
| | - Xiaolin Dong
- Chemistry Section, Stockholm University, 10691 Stockholm, Sweden
| | - Jüri Jarvet
- Chemistry Section, Stockholm University, 10691 Stockholm, Sweden
- The National Institute of Chemical Physics and Biophysics, 12618 Tallinn, Estonia
| | - Željko M Svedružić
- Department of Biotechnology, University of Rijeka, HR 51000 Rijeka, Croatia
| | - Astrid Gräslund
- Chemistry Section, Stockholm University, 10691 Stockholm, Sweden
| | - Maciej Kozak
- Department of Macromolecular Physics, Faculty of Physics, Adam Mickiewicz University, PL 61-614 Poznań, Poland
- National Synchrotron Radiation Centre SOLARIS, Jagiellonian University, PL 30-392 Kraków, Poland
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Suh JM, Kim M, Yoo J, Han J, Paulina C, Lim MH. Intercommunication between metal ions and amyloidogenic peptides or proteins in protein misfolding disorders. Coord Chem Rev 2023. [DOI: 10.1016/j.ccr.2022.214978] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Abstract
Amyloids are protein aggregates bearing a highly ordered cross β structural motif, which may be functional but are mostly pathogenic. Their formation, deposition in tissues and consequent organ dysfunction is the central event in amyloidogenic diseases. Such protein aggregation may be brought about by conformational changes, and much attention has been directed toward factors like metal binding, post-translational modifications, mutations of protein etc., which eventually affect the reactivity and cytotoxicity of the associated proteins. Over the past decade, a global effort from different groups working on these misfolded/unfolded proteins/peptides has revealed that the amino acid residues in the second coordination sphere of the active sites of amyloidogenic proteins/peptides cause changes in H-bonding pattern or protein-protein interactions, which dramatically alter the structure and reactivity of these proteins/peptides. These second sphere effects not only determine the binding of transition metals and cofactors, which define the pathology of some of these diseases, but also change the mechanism of redox reactions catalyzed by these proteins/peptides and form the basis of oxidative damage associated with these amyloidogenic diseases. The present review seeks to discuss such second sphere modifications and their ramifications in the etiopathology of some representative amyloidogenic diseases like Alzheimer's disease (AD), type 2 diabetes mellitus (T2Dm), Parkinson's disease (PD), Huntington's disease (HD), and prion diseases.
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Affiliation(s)
- Madhuparna Roy
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A & 2B, Raja S. C. Mullick Road, Jadavpur, Kolkata 700032, India
| | - Arnab Kumar Nath
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A & 2B, Raja S. C. Mullick Road, Jadavpur, Kolkata 700032, India
| | - Ishita Pal
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A & 2B, Raja S. C. Mullick Road, Jadavpur, Kolkata 700032, India
| | - Somdatta Ghosh Dey
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A & 2B, Raja S. C. Mullick Road, Jadavpur, Kolkata 700032, India
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Daude N, Lau A, Vanni I, Kang SG, Castle AR, Wohlgemuth S, Dorosh L, Wille H, Stepanova M, Westaway D. Prion protein with a mutant N-terminal octarepeat region undergoes cobalamin-dependent assembly into high-molecular weight complexes. J Biol Chem 2022; 298:101770. [PMID: 35271850 PMCID: PMC9010764 DOI: 10.1016/j.jbc.2022.101770] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 02/16/2022] [Accepted: 02/17/2022] [Indexed: 11/28/2022] Open
Abstract
The cellular prion protein (PrPC) has a C-terminal globular domain and a disordered N-terminal region encompassing five octarepeats (ORs). Encounters between Cu(II) ions and four OR sites produce interchangeable binding geometries; however, the significance of Cu(II) binding to ORs in different combinations is unclear. To understand the impact of specific binding geometries, OR variants were designed that interact with multiple or single Cu(II) ions in specific locked coordinations. Unexpectedly, we found that one mutant produced detergent-insoluble, protease-resistant species in cells in the absence of exposure to the infectious prion protein isoform, scrapie-associated prion protein (PrPSc). Formation of these assemblies, visible as puncta, was reversible and dependent upon medium formulation. Cobalamin (Cbl), a dietary cofactor containing a corrin ring that coordinates a Co3+ ion, was identified as a key medium component, and its effect was validated by reconstitution experiments. Although we failed to find evidence that Cbl interacts with Cu-binding OR regions, we instead noted interactions of Cbl with the PrPC C-terminal domain. We found that some interactions occurred at a binding site of planar tetrapyrrole compounds on the isolated globular domain, but others did not, and N-terminal sequences additionally had a marked effect on their presence and position. Our studies define a conditional effect of Cbl wherein a mutant OR region can act in cis to destabilize a globular domain with a wild type sequence. The unexpected intersection between the properties of PrPSc's disordered region, Cbl, and conformational remodeling events may have implications for understanding sporadic prion disease that does not involve exposure to PrPSc.
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Affiliation(s)
- Nathalie Daude
- Centre for Prions and Protein Folding Diseases, University of Alberta, Canada
| | - Agnes Lau
- Centre for Prions and Protein Folding Diseases, University of Alberta, Canada
| | - Ilaria Vanni
- Department of Food Safety, Nutrition and Veterinary Public Health, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161, Rome, Italy
| | - Sang-Gyun Kang
- Centre for Prions and Protein Folding Diseases, University of Alberta, Canada
| | - Andrew R Castle
- Centre for Prions and Protein Folding Diseases, University of Alberta, Canada
| | - Serene Wohlgemuth
- Centre for Prions and Protein Folding Diseases, University of Alberta, Canada
| | - Lyudmyla Dorosh
- Faculty of Engineering - Electrical & Computer Engineering Dept, University of Alberta, Canada
| | - Holger Wille
- Centre for Prions and Protein Folding Diseases, University of Alberta, Canada; Department of Biochemistry, University of Alberta, Canada
| | - Maria Stepanova
- Faculty of Engineering - Electrical & Computer Engineering Dept, University of Alberta, Canada
| | - David Westaway
- Centre for Prions and Protein Folding Diseases, University of Alberta, Canada.
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Gielnik M, Taube M, Zhukova L, Zhukov I, Wärmländer SKTS, Svedružić Ž, Kwiatek WM, Gräslund A, Kozak M. Zn(II) binding causes interdomain changes in the structure and flexibility of the human prion protein. Sci Rep 2021; 11:21703. [PMID: 34737343 PMCID: PMC8568922 DOI: 10.1038/s41598-021-00495-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Accepted: 10/05/2021] [Indexed: 12/31/2022] Open
Abstract
The cellular prion protein (PrPC) is a mainly α-helical 208-residue protein located in the pre- and postsynaptic membranes. For unknown reasons, PrPC can undergo a structural transition into a toxic, β-sheet rich scrapie isoform (PrPSc) that is responsible for transmissible spongiform encephalopathies (TSEs). Metal ions seem to play an important role in the structural conversion. PrPC binds Zn(II) ions and may be involved in metal ion transport and zinc homeostasis. Here, we use multiple biophysical techniques including optical and NMR spectroscopy, molecular dynamics simulations, and small angle X-ray scattering to characterize interactions between human PrPC and Zn(II) ions. Binding of a single Zn(II) ion to the PrPC N-terminal domain via four His residues from the octarepeat region induces a structural transition in the C-terminal α-helices 2 and 3, promotes interaction between the N-terminal and C-terminal domains, reduces the folded protein size, and modifies the internal structural dynamics. As our results suggest that PrPC can bind Zn(II) under physiological conditions, these effects could be important for the physiological function of PrPC.
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Affiliation(s)
- Maciej Gielnik
- Department of Macromolecular Physics, Faculty of Physics, Adam Mickiewicz University, 61-614, Poznań, Poland
| | - Michał Taube
- Department of Macromolecular Physics, Faculty of Physics, Adam Mickiewicz University, 61-614, Poznań, Poland
| | - Lilia Zhukova
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02-106, Warszawa, Poland
| | - Igor Zhukov
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02-106, Warszawa, Poland
| | | | - Željko Svedružić
- Department of Biotechnology, University of Rijeka, 51000, Rijeka, Croatia
| | - Wojciech M Kwiatek
- Institute of Nuclear Physics Polish Academy of Sciences, 31-342, Kraków, Poland
| | - Astrid Gräslund
- Department of Biochemistry and Biophysics, Stockholm University, 10691, Stockholm, Sweden
| | - Maciej Kozak
- Department of Macromolecular Physics, Faculty of Physics, Adam Mickiewicz University, 61-614, Poznań, Poland.
- National Synchrotron Radiation Centre SOLARIS, Jagiellonian University, 30-392, Kraków, Poland.
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Nochebuena J, Quintanar L, Vela A, Cisneros GA. Structural and electronic analysis of the octarepeat region of prion protein with four Cu 2+ by polarizable MD and QM/MM simulations. Phys Chem Chem Phys 2021; 23:21568-21578. [PMID: 34550129 PMCID: PMC8497436 DOI: 10.1039/d1cp03187b] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Prions have been linked to neurodegenerative diseases that affect various species of mammals including humans. The prion protein, located mainly in neurons, is believed to play the role of metal ion transporter. High levels of copper ions have been related to structural changes. A 32-residue region of the N-terminal domain, known as octarepeat, can bind up to four copper ions. Different coordination modes have been observed and are strongly dependent on Cu2+ concentration. Many theoretical studies carried out so far have focused on studying the coordination modes of a single copper ion. In this work we investigate the octarepeat region coordinated with four copper ions. Molecular dynamics (MD) and hybrid quantum mechanics/molecular mechanics (QM/MM) simulations using the polarizable AMOEBA force field have been carried out. The polarizable MD simulations starting from a fully extended conformation indicate that the tetra-Cu2+/octarepeat complex forms a globular structure. The globular form is stabilized by interactions between Cu2+ and tryptophan residues resulting in some coordination sites observed to be in close proximity, in agreement with experimental results. Subsequent QM/MM simulations on several snapshots suggests the system is in a high-spin quintet state, with all Cu2+ bearing one single electron, and all unpaired electrons are ferromagnetically coupled. NMR simulations on selected structures provides insights on the chemical shifts of the first shell ligands around the metals with respect to inter-metal distances.
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Affiliation(s)
- Jorge Nochebuena
- Department of Chemistry, University of North Texas, Denton, Texas, 76201, USA.
| | - Liliana Quintanar
- Centro de Investigación y de Estudios Avanzados del IPN, Mexico City, 07360, Mexico
| | - Alberto Vela
- Centro de Investigación y de Estudios Avanzados del IPN, Mexico City, 07360, Mexico
| | - G Andrés Cisneros
- Department of Chemistry, University of North Texas, Denton, Texas, 76201, USA.
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Roseman GP, Wu B, Wadolkowski MA, Harris DA, Millhauser GL. Intrinsic toxicity of the cellular prion protein is regulated by its conserved central region. FASEB J 2020; 34:8734-8748. [PMID: 32385908 DOI: 10.1096/fj.201902749rr] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 04/08/2020] [Accepted: 04/20/2020] [Indexed: 11/11/2022]
Abstract
The conserved central region (CR) of PrPC has been hypothesized to serve as a passive linker connecting the protein's toxic N-terminal and globular C-terminal domains. Yet, deletion of the CR causes neonatal fatality in mice, implying the CR possesses a protective function. The CR encompasses the regulatory α-cleavage locus, and additionally facilitates a regulatory metal ion-promoted interaction between the PrPC N- and C-terminal domains. To elucidate the role of the CR and determine why CR deletion generates toxicity, we designed PrPC constructs wherein either the cis-interaction or α-cleavage are selectively prevented. These constructs were interrogated using nuclear magnetic resonance, electrophysiology, and cell viability assays. Our results demonstrate the CR is not a passive linker and the native sequence is crucial for its protective role over the toxic N-terminus, irrespective of α-cleavage or the cis-interaction. Additionally, we find that the CR facilitates homodimerization of PrPC , attenuating the toxicity of the N-terminus.
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Affiliation(s)
- Graham P Roseman
- Department of Chemistry and Biochemistry, University of California Santa Cruz, Santa Cruz, CA, USA
| | - Bei Wu
- Department of Biochemistry, Boston University School of Medicine, Boston, MA, USA
| | - Mark A Wadolkowski
- Department of Chemistry and Biochemistry, University of California Santa Cruz, Santa Cruz, CA, USA
| | - David A Harris
- Department of Biochemistry, Boston University School of Medicine, Boston, MA, USA
| | - Glenn L Millhauser
- Department of Chemistry and Biochemistry, University of California Santa Cruz, Santa Cruz, CA, USA
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Bernardi L, Bruni AC. Mutations in Prion Protein Gene: Pathogenic Mechanisms in C-Terminal vs. N-Terminal Domain, a Review. Int J Mol Sci 2019; 20:E3606. [PMID: 31340582 PMCID: PMC6678283 DOI: 10.3390/ijms20143606] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Revised: 07/07/2019] [Accepted: 07/15/2019] [Indexed: 12/21/2022] Open
Abstract
Inherited mutations in the Prion protein (PrP), encoded by the PRNP gene, have been associated with autosomal dominant neurodegenerative disorders, such as Creutzfeldt-Jacob disease (CJD), Gerstmann-Sträussler-Scheinker syndrome (GSS), and Fatal Familial Insomnia (FFI). Notably, PRNP mutations have also been described in clinical pictures resembling other neurodegenerative diseases, such as frontotemporal dementia. Regarding the pathogenesis, it has been observed that these point mutations are located in the C-terminal region of the PRNP gene and, currently, the potential significance of the N-terminal domain has largely been underestimated. The purpose of this report is to review and provide current insights into the pathogenic mechanisms of PRNP mutations, emphasizing the differences between the C- and N-terminal regions and focusing, in particular, on the lesser-known flexible N-terminal, for which recent biophysical evidence has revealed a physical interaction with the globular C-terminal domain of the cellular prion protein (PrPC).
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Affiliation(s)
- Livia Bernardi
- Regional Neurogenetic Centre, ASP Catanzaro, 88046 Lamezia Terme (CZ), Italy
| | - Amalia C Bruni
- Regional Neurogenetic Centre, ASP Catanzaro, 88046 Lamezia Terme (CZ), Italy.
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