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Li Q, Zhu Y, Meng X, Tong HHY, Liu H. Experiment and molecular dynamics simulations reveal proanthocyanidin B2 and B3 can inhibit prion aggregation by different mechanisms. J Biomol Struct Dyn 2024; 42:2424-2436. [PMID: 37144732 DOI: 10.1080/07391102.2023.2209663] [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: 12/28/2022] [Accepted: 04/14/2023] [Indexed: 05/06/2023]
Abstract
Prion diseases are a group of fatal neurodegenerative diseases caused by the misfolding and aggregation of prion protein (PrP), and the inhibition of PrP aggregation is one of the most effective therapeutic strategies. Proanthocyanidin B2 (PB2) and B3 (PB3), the effective natural antioxidants have been evaluated for the inhibition of amyloid-related protein aggregation. Since PrP has similar aggregation mechanism with other amyloid-related proteins, will PB2 and PB3 affect the aggregation of PrP? In this paper, experimental and molecular dynamics (MD) simulation methods were combined to investigate the influence of PB2 and PB3 on PrP aggregation. Thioflavin T assays showed PB2 and PB3 could inhibit PrP aggregation in a concentrate-dependent manner in vitro. To understand the underlying mechanism, we performed 400 ns all-atom MD simulations. The results suggested PB2 could stabilize the α2 C-terminus and the hydrophobic core of protein by stabilizing two important salt bridges R156-E196 and R156-D202, and consequently made global structure of protein more stable. Surprisingly, PB3 could not stabilize PrP, which may inhibit PrP aggregation through a different mechanism. Since dimerization is the first step of aggregation, will PB3 inhibit PrP aggregation by inhibiting the dimerization? To verify our assumption, we then explored the effect of PB3 on protein dimerization by performing 800 ns MD simulations. The results suggested PB3 could reduce the residue contacts and hydrogen bonds between two monomers, preventing dimerization process of PrP. The possible inhibition mechanism of PB2 and PB3 on PrP aggregation could provide useful information for drug development against prion diseases.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Qin Li
- Faculty of Applied Sciences, Macao Polytechnic University, Macao, SAR, China
| | - Yongchang Zhu
- College of Chemical Engineering, Shijiazhuang University, Shijiazhuang, China
| | - Xiaoxiao Meng
- School of Pharmacy, Lanzhou University, Lanzhou, China
| | - Henry H Y Tong
- Faculty of Applied Sciences, Macao Polytechnic University, Macao, SAR, China
| | - Huanxiang Liu
- Faculty of Applied Sciences, Macao Polytechnic University, Macao, SAR, China
- School of Pharmacy, Lanzhou University, Lanzhou, China
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2
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L P Hosszu L, Sangar D, Batchelor M, Risse E, Hounslow AM, Collinge J, Waltho JP, Bieschke J. Loss of residues 119 - 136, including the first β-strand of human prion protein, generates an aggregation-competent partially "open" form. J Mol Biol 2023:168158. [PMID: 37244570 DOI: 10.1016/j.jmb.2023.168158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 05/18/2023] [Accepted: 05/19/2023] [Indexed: 05/29/2023]
Abstract
In prion replication, the cellular form of prion protein (PrPC) must undergo a full conformational transition to its disease-associated fibrillar form. Transmembrane forms of PrP have been implicated in this structural conversion. The cooperative unfolding of a structural core in PrPC presents a substantial energy barrier to prion formation, with membrane insertion and detachment of parts of PrP presenting a plausible route to its reduction. Here, we examined the removal of residues 119 - 136 of PrP, a region which includes the first β-strand and a substantial portion of the conserved hydrophobic region of PrP, a region which associates with the ER membrane, on the structure, stability and self-association of the folded domain of PrPC. We see an "open" native-like conformer with increased solvent exposure which fibrilises more readily than the native state. These data suggest a stepwise folding transition, which is initiated by the conformational switch to this "open" form of PrPC.
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Affiliation(s)
- Laszlo L P Hosszu
- MRC Prion Unit at UCL, UCL Institute of Prion Diseases, 33 Cleveland Street, London, W1W 7FF, UK
| | - Daljit Sangar
- MRC Prion Unit at UCL, UCL Institute of Prion Diseases, 33 Cleveland Street, London, W1W 7FF, UK
| | - Mark Batchelor
- MRC Prion Unit at UCL, UCL Institute of Prion Diseases, 33 Cleveland Street, London, W1W 7FF, UK
| | - Emmanuel Risse
- MRC Prion Unit at UCL, UCL Institute of Prion Diseases, 33 Cleveland Street, London, W1W 7FF, UK
| | - Andrea M Hounslow
- Department of Molecular Biology and Biotechnology, University of Sheffield, Firth Court, Western Bank, Sheffield S10 2TN, UK
| | - John Collinge
- MRC Prion Unit at UCL, UCL Institute of Prion Diseases, 33 Cleveland Street, London, W1W 7FF, UK
| | - Jonathan P Waltho
- Department of Molecular Biology and Biotechnology, University of Sheffield, Firth Court, Western Bank, Sheffield S10 2TN, UK; Manchester Institute of Biotechnology, University of Manchester, 131 Princess Street, Manchester, M1 7DN, UK
| | - Jan Bieschke
- MRC Prion Unit at UCL, UCL Institute of Prion Diseases, 33 Cleveland Street, London, W1W 7FF, UK.
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3
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Zuo K, Kranjc A, Capelli R, Rossetti G, Nechushtai R, Carloni P. Metadynamics simulations of ligands binding to protein surfaces: a novel tool for rational drug design. Phys Chem Chem Phys 2023; 25:13819-13824. [PMID: 37184538 DOI: 10.1039/d3cp01388j] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Structure-based drug design protocols may encounter difficulties to investigate poses when the biomolecular targets do not exhibit typical binding pockets. In this study, by providing two concrete examples from our labs, we suggest that the combination of metadynamics free energy methods (validated against affinity measurements), along with experimental structural information (by X-ray crystallography and NMR), can help to identify the poses of ligands on protein surfaces. The simulation workflow proposed here was implemented in a widely used code, namely GROMACS, and it could straightforwardly be applied to various drug-design campaigns targeting ligands' binding to protein surfaces.
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Affiliation(s)
- Ke Zuo
- Computational Biomedicine, Institute of Advanced Simulation IAS-5 and Institute of Neuroscience and Medicine INM-9, Forschungszentrum Jülich GmbH, Jülich 52425, Germany.
- Department of Physics, RWTH Aachen University, Aachen 52074, Germany
- The Alexander Silberman Institute of Life Science, The Hebrew University of Jerusalem, Edmond J. Safra Campus at Givat Ram, Jerusalem 91904, Israel
- Department of Physics, Università degli Studi di Ferrara, Ferrara 44121, Italy
| | - Agata Kranjc
- Computational Biomedicine, Institute of Advanced Simulation IAS-5 and Institute of Neuroscience and Medicine INM-9, Forschungszentrum Jülich GmbH, Jülich 52425, Germany.
| | - Riccardo Capelli
- Department of Biosciences, Università degli Studi di Milano, Via Celoria 26, Milan 20133, Italy
| | - Giulia Rossetti
- Computational Biomedicine, Institute of Advanced Simulation IAS-5 and Institute of Neuroscience and Medicine INM-9, Forschungszentrum Jülich GmbH, Jülich 52425, Germany.
- Jülich Supercomputing Center (JSC), Forschungszentrum Jülich GmbH, Jülich 52425, Germany
- Department of Neurology, Faculty of Medicine, RWTH Aachen University, Aachen 52074, Germany
| | - Rachel Nechushtai
- The Alexander Silberman Institute of Life Science, The Hebrew University of Jerusalem, Edmond J. Safra Campus at Givat Ram, Jerusalem 91904, Israel
| | - Paolo Carloni
- Computational Biomedicine, Institute of Advanced Simulation IAS-5 and Institute of Neuroscience and Medicine INM-9, Forschungszentrum Jülich GmbH, Jülich 52425, Germany.
- Department of Physics, RWTH Aachen University, Aachen 52074, Germany
- JARA Institute: Molecular Neuroscience and Imaging, Institute of Neuroscience and Medicine INM-11, Forschungszentrum Jülich GmbH, Jülich 52425, Germany
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4
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Gharemirshamloo FR, Majumder R, Kumar S U, Doss C GP, Bamdad K, Frootan F, Un C. Effects of the pathological E200K mutation on human prion protein: A computational screening and molecular dynamics approach. J Cell Biochem 2023; 124:254-265. [PMID: 36565210 DOI: 10.1002/jcb.30359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Revised: 12/06/2022] [Accepted: 12/08/2022] [Indexed: 12/25/2022]
Abstract
The human prion protein gene (PRNP) is mapped to the short arm of chromosome 20 (20pter-12). Prion disease is associated with mutations in the prion protein-encoding gene sequence. Earlier studies found that the mutation G127V in the PRNP increases protein stability. In contrast, the mutation E200K, which has the highest mutation rate in the prion protein, causes Creutzfeldt-Jakob disease (CJD) in humans and induces protein aggregation. We aimed to identify the structural mechanisms of E200k and G127V mutations causing CJD. We used a variety of bioinformatic algorithms, including SIFT, PolyPhen, I-Mutant, PhD-SNP, and SNP& GO, to predict the association of the E200K mutation with prion disease. MD simulation is performed, and graphs for root mean square deviation, root mean square fluctuation, radius of gyration, DSSP, principal component analysis, porcupine, and free energy landscape are generated to confirm and prove the stability of the wild-type and mutant protein structures. The protein is analyzed for aggregation, and the results indicate more fluctuations in the protein structure during the simulation owing to the E200K mutation; however, the G127V mutation makes the protein structure stable against aggregation during the simulation.
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Affiliation(s)
| | - Ranabir Majumder
- School of Medical Science and Technology, Indian Institute of Technology Kharagpur, Kharagpur, India
| | - Udhaya Kumar S
- Department of Integrative Biology, Laboratory of Integrative Genomics, School of Bio Sciences and Technology, Vellore Institute of Technology (VIT), Vellore, Tamil Nadu, India
| | - George Priya Doss C
- Department of Integrative Biology, Laboratory of Integrative Genomics, School of Bio Sciences and Technology, Vellore Institute of Technology (VIT), Vellore, Tamil Nadu, India
| | - Kourosh Bamdad
- Department of Biology, Payame Noor University, Tehran, Iran
| | - Fateme Frootan
- Institute of Agricultural Biotechnology, National Institute of Genetic Engineering & Biotechnology (NIGEB), Tehran, Iran
| | - Cemal Un
- Department of Biology, Division of Molecular Biology, Ege University, Izmir, Turkey
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5
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Xia K, Shen H, Wang P, Tan R, Xun D. Investigation of the conformation of human prion protein in ethanol solution using molecular dynamics simulations. J Biomol Struct Dyn 2022:1-10. [PMID: 35838152 DOI: 10.1080/07391102.2022.2099466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
When the conformation of protein is changed from its natural state to a misfolded state, some diseases will happen like prion disease. Prion diseases are a set of deadly neurodegenerative diseases caused by prion protein misfolding and aggregation. Monohydric alcohols have a strong influence on the structure of protein. However, whether monohydric alcohols inhibit amyloid fibrosis remains uncertain. Here, to elucidate the effect of ethanol on the structural stability of human prion protein, molecular dynamics simulations were employed to analyze the conformational changes and dynamics characteristics of human prion proteins at different temperatures. The results show that the extension of β-sheet occurs more easily and the α-helix is more easily disrupted at high temperatures. We found that ethanol can destroy the hydrophobic interactions and make the hydrogen bonds stable, which protects the secondary structure of the protein, especially at 500 K.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Kui Xia
- Department of Physics, Jiangxi Science and Technology Normal University, Nanchang, China
| | - Haolei Shen
- Department of Physics, Jiangxi Science and Technology Normal University, Nanchang, China
| | - Peng Wang
- Department of Physics, Jiangxi Science and Technology Normal University, Nanchang, China
| | - Rongri Tan
- Department of Physics, Jiangxi Science and Technology Normal University, Nanchang, China
| | - Damao Xun
- Department of Physics, Jiangxi Science and Technology Normal University, Nanchang, China
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6
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Roterman I, Stapor K, Gądek K, Gubała T, Nowakowski P, Fabian P, Konieczny L. On the Dependence of Prion and Amyloid Structure on the Folding Environment. Int J Mol Sci 2021; 22:ijms222413494. [PMID: 34948291 PMCID: PMC8707753 DOI: 10.3390/ijms222413494] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Revised: 12/13/2021] [Accepted: 12/14/2021] [Indexed: 01/22/2023] Open
Abstract
Currently available analyses of amyloid proteins reveal the necessity of the existence of radical structural changes in amyloid transformation processes. The analysis carried out in this paper based on the model called fuzzy oil drop (FOD) and its modified form (FOD-M) allows quantifying the role of the environment, particularly including the aquatic environment. The starting point and basis for the present presentation is the statement about the presence of two fundamentally different methods of organizing polypeptides into ordered conformations—globular proteins and amyloids. The present study shows the source of the differences between these two paths resulting from the specificity of the external force field coming from the environment, including the aquatic and hydrophobic one. The water environment expressed in the fuzzy oil drop model using the 3D Gauss function directs the folding process towards the construction of a micelle-like system with a hydrophobic core in the central part and the exposure of polarity on the surface. The hydrophobicity distribution of membrane proteins has the opposite characteristic: Exposure of hydrophobicity at the surface of the membrane protein with an often polar center (as in the case of ion channels) is expected. The structure of most proteins is influenced by a more or less modified force field generated by water through the appropriate presence of a non-polar (membrane-like) environment. The determination of the proportion of a factor different from polar water enables the assessment of the protein status by indicating factors favoring the structure it represents.
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Affiliation(s)
- Irena Roterman
- Department of Bioinformatics and Telemedicine, Jagiellonian University Medical College, 31-034 Kopernika 7, 30-688 Krakow, Poland
- Correspondence:
| | - Katarzyna Stapor
- Department of Applied Informatics, Silesian University of Technology, Akademicka 16, 44-100 Gliwice, Poland;
| | - Krzysztof Gądek
- Sano Centre for Computation Medicine, Czarnowiejska 36, 30-054 Kraków, Poland; (K.G.); (T.G.); (P.N.)
| | - Tomasz Gubała
- Sano Centre for Computation Medicine, Czarnowiejska 36, 30-054 Kraków, Poland; (K.G.); (T.G.); (P.N.)
| | - Piotr Nowakowski
- Sano Centre for Computation Medicine, Czarnowiejska 36, 30-054 Kraków, Poland; (K.G.); (T.G.); (P.N.)
| | - Piotr Fabian
- Department of Algorithmics and Software, Silesian University of Technology, Akademicka 16, 44-100 Gliwice, Poland;
| | - Leszek Konieczny
- Department of Medical Biochemistry, Jagiellonian University Medical College, 31-034 Kopernika 7, 31-034 Krakow, Poland;
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7
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Adhikari UK, Tayebi M. Epitope-specific anti-PrP antibody toxicity: a comparative in-silico study of human and mouse prion proteins. Prion 2021; 15:155-176. [PMID: 34632945 PMCID: PMC8900626 DOI: 10.1080/19336896.2021.1964326] [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] [Indexed: 10/24/2022] Open
Abstract
Despite having therapeutic potential, anti-PrP antibodies caused a major controversy due to their neurotoxic effects. For instance, treating mice with ICSM antibodies delayed prion disease onset, but both were found to be either toxic or innocuous to neurons by researchers following cross-linking PrPC. In order to elucidate and understand the reasons that led to these contradictory outcomes, we conducted a comprehensive in silico study to assess the antibody-specific toxicity. Since most therapeutic anti-PrP antibodies were generated against human truncated recombinant PrP91-231 or full-length mouse PrP23-231, we reasoned that host specificity (human vs murine) of PrPC might influence the nature of the specific epitopes recognized by these antibodies at the structural level possibly explaining the 'toxicity' discrepancies reported previously. Initially, molecular dynamics simulation and pro-motif analysis of full-length human (hu)PrP and mouse (mo)PrP 3D structure displayed conspicuous structural differences between huPrP and moPrP. We identified 10 huPrP and 6 moPrP linear B-cell epitopes from the prion protein 3D structure where 5 out of 10 huPrP and 3 out of 6 moPrP B-cell epitopes were predicted to be potentially toxic in immunoinformatics approaches. Herein, we demonstrate that some of the predicted potentially 'toxic' epitopes identified by the in silico analysis were similar to the epitopes recognized by the toxic antibodies such as ICSM18 (146-159), POM1 (138-147), D18 (133-157), ICSM35 (91-110), D13 (95-103) and POM3 (95-100). This in silico study reveals the role of host specificity of PrPC in epitope-specific anti-PrP antibody toxicity.
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Affiliation(s)
| | - Mourad Tayebi
- School of Medicine, Western Sydney University, Campbelltown, NSW, Australia
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8
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Bhate SH, Udgaonkar JB, Das R. Destabilization of polar interactions in the prion protein triggers misfolding and oligomerization. Protein Sci 2021; 30:2258-2271. [PMID: 34558139 DOI: 10.1002/pro.4188] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2021] [Revised: 09/15/2021] [Accepted: 09/16/2021] [Indexed: 12/25/2022]
Abstract
The prion protein (PrP) misfolds and oligomerizes at pH 4 in the presence of physiological salt concentrations. Low pH and salt cause structural perturbations in the monomeric prion protein that lead to misfolding and oligomerization. However, the changes in stability within different regions of the PrP prior to oligomerization are poorly understood. In this study, we have characterized the local stability in PrP at high resolution using amide temperature coefficients (TC ) measured by nuclear magnetic resonance (NMR) spectroscopy. The local stability of PrP was investigated under native as well as oligomerizing conditions. We have also studied the rapidly oligomerizing PrP variant (Q216R) and the protective PrP variant (A6). We report that at low pH, salt destabilizes PrP at several polar residues, and the hydrogen bonds in helices α2 and α3 are weakened. In addition, salt changes the curvature of the α3 helix, which likely disrupts α2-α3 contacts and leads to oligomerization. These results are corroborated by the TC values of rapidly oligomerizing Q216R-PrP. The poly-alanine substitution in A6-PrP stabilizes α2, which prevents oligomerization. Altogether, these results highlight the importance of native polar interactions in determining the stability of PrP and reveal the structural disruptions in PrP that lead to misfolding and oligomerization.
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Affiliation(s)
- Suhas H Bhate
- National Centre for Biological Sciences, TIFR, Bangalore, India
| | - Jayant B Udgaonkar
- National Centre for Biological Sciences, TIFR, Bangalore, India.,Indian Institute for Science Education and Research, Pune, India
| | - Ranabir Das
- National Centre for Biological Sciences, TIFR, Bangalore, India
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9
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Palaniappan C, Narayanan RC, Sekar K. Mutation-Dependent Refolding of Prion Protein Unveils Amyloidogenic-Related Structural Ramifications: Insights from Molecular Dynamics Simulations. ACS Chem Neurosci 2021; 12:2810-2819. [PMID: 34296847 DOI: 10.1021/acschemneuro.1c00142] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The main focus of prion structural biology studies is to understand the molecular basis of prion diseases caused by misfolding, and aggregation of the cellular prion protein PrPC remains elusive. Several genetic mutations are linked with human prion diseases and driven by the conformational conversion of PrPC to the toxic PrPSc. The main goal of this study is to gain a better insight into the molecular effect of disease-associated V210I mutation on this process by molecular dynamics simulations. This inherited mutation elicited copious structural changes in the β1-α1-β2 subdomain, including an unfolding of a helix α1 and the elongation of the β-sheet. These unusual structural changes likely appeared to detach the β1-α1-β2 subdomain from the α2-α3 core, an early misfolding event necessary for the conformational conversion of PrPC to PrPSc. Ultimately, the unfolded α1 and its prior β1-α1 loop further engaged with unrestrained conformational dynamics and were widely considered as amyloidogenic-inducing traits. Furthermore, the resulting folding intermediate possesses a highly unstable β1-α1-β2 subdomain, thereby enhancing the aggregation of misfolded PrPC through intermolecular interactions between frequently refolding regions. Briefly, these remarkable changes as seen in the mutant β1-α1-β2 subdomain are consistent with previous experimental results and thus provide a molecular basis of PrPC misfolding associated with the conformational conversion of PrPC to PrPSc.
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Affiliation(s)
| | - Rahul C. Narayanan
- Department of Computational and Data Sciences, Indian Institute of Science, Bangalore 560 012, India
| | - Kanagaraj Sekar
- Department of Computational and Data Sciences, Indian Institute of Science, Bangalore 560 012, India
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10
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Mechanism of misfolding of the human prion protein revealed by a pathological mutation. Proc Natl Acad Sci U S A 2021; 118:2019631118. [PMID: 33731477 PMCID: PMC7999870 DOI: 10.1073/pnas.2019631118] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The misfolding and aggregation of the human prion protein (PrP) is associated with transmissible spongiform encephalopathies (TSEs). Intermediate conformations forming during the conversion of the cellular form of PrP into its pathological scrapie conformation are key drivers of the misfolding process. Here, we analyzed the properties of the C-terminal domain of the human PrP (huPrP) and its T183A variant, which is associated with familial forms of TSEs. We show that the mutation significantly enhances the aggregation propensity of huPrP, such as to uniquely induce amyloid formation under physiological conditions by the sole C-terminal domain of the protein. Using NMR spectroscopy, biophysics, and metadynamics simulations, we identified the structural characteristics of the misfolded intermediate promoting the aggregation of T183A huPrP and the nature of the interactions that prevent this species to be populated in the wild-type protein. In support of these conclusions, POM antibodies targeting the regions that promote PrP misfolding were shown to potently suppress the aggregation of this amyloidogenic mutant.
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11
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Structural details of amyloid β oligomers in complex with human prion protein as revealed by solid-state MAS NMR spectroscopy. J Biol Chem 2021; 296:100499. [PMID: 33667547 PMCID: PMC8042448 DOI: 10.1016/j.jbc.2021.100499] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 02/24/2021] [Accepted: 03/01/2021] [Indexed: 02/06/2023] Open
Abstract
Human PrP (huPrP) is a high-affinity receptor for oligomeric amyloid β (Aβ) protein aggregates. Binding of Aβ oligomers to membrane-anchored huPrP has been suggested to trigger neurotoxic cell signaling in Alzheimer’s disease, while an N-terminal soluble fragment of huPrP can sequester Aβ oligomers and reduce their toxicity. Synthetic oligomeric Aβ species are known to be heterogeneous, dynamic, and transient, rendering their structural investigation particularly challenging. Here, using huPrP to preserve Aβ oligomers by coprecipitating them into large heteroassemblies, we investigated the conformations of Aβ(1–42) oligomers and huPrP in the complex by solid-state MAS NMR spectroscopy. The disordered N-terminal region of huPrP becomes immobilized in the complex and therefore visible in dipolar spectra without adopting chemical shifts characteristic of a regular secondary structure. Most of the well-defined C-terminal part of huPrP is part of the rigid complex, and solid-state NMR spectra suggest a loss in regular secondary structure in the two C-terminal α-helices. For Aβ(1–42) oligomers in complex with huPrP, secondary chemical shifts reveal substantial β-strand content. Importantly, not all Aβ(1–42) molecules within the complex have identical conformations. Comparison with the chemical shifts of synthetic Aβ fibrils suggests that the Aβ oligomer preparation represents a heterogeneous mixture of β-strand-rich assemblies, of which some have the potential to evolve and elongate into different fibril polymorphs, reflecting a general propensity of Aβ to adopt variable β-strand-rich conformers. Taken together, our results reveal structural changes in huPrP upon binding to Aβ oligomers that suggest a role of the C terminus of huPrP in cell signaling. Trapping Aβ(1–42) oligomers by binding to huPrP has proved to be a useful tool for studying the structure of these highly heterogeneous β-strand-rich assemblies.
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12
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Shoup D, Priola SA. The Size and Stability of Infectious Prion Aggregates Fluctuate Dynamically during Cellular Uptake and Disaggregation. Biochemistry 2021; 60:398-411. [PMID: 33497187 DOI: 10.1021/acs.biochem.0c00923] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Prion diseases arise when PrPSc, an aggregated, infectious, and insoluble conformer of the normally soluble mammalian prion protein, PrPC, catalyzes the conversion of PrPC into more PrPSc, which then accumulates in the brain leading to disease. PrPSc is the primary, if not sole, component of the infectious prion. Despite the stability and protease insensitivity of PrPSc aggregates, they can be degraded after cellular uptake. However, how cells disassemble and degrade PrPSc is poorly understood. In this work, we analyzed how the protease sensitivity and size distribution of PrPSc aggregates from two different mouse-adapted prion strains, 22L, that can persistently infect cells and 87V, that cannot, changed during cellular uptake. We show that within the first 4 h following uptake large PrPSc aggregates from both prion strains become less resistant to digestion by proteinase K (PK) through a mechanism that is dependent upon the acidic environment of endocytic vesicles. We further show that during disassembly, PrPSc aggregates from both strains become more resistant to PK digestion through the apparent removal of protease-sensitive PrPSc, with PrPSc from the 87V strain disassembled more readily than PrPSc from the 22L strain. Taken together, our data demonstrate that the sizes and stabilities of PrPSc from different prion strains change during cellular uptake and degradation, thereby potentially impacting the ability of prions to infect cells.
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Affiliation(s)
- Daniel Shoup
- Rocky Mountain Laboratories, Laboratory of Persistent Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana 59840, United States
| | - Suzette A Priola
- Rocky Mountain Laboratories, Laboratory of Persistent Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana 59840, United States
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13
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Reidenbach AG, Mesleh MF, Casalena D, Vallabh SM, Dahlin JL, Leed AJ, Chan AI, Usanov DL, Yehl JB, Lemke CT, Campbell AJ, Shah RN, Shrestha OK, Sacher JR, Rangel VL, Moroco JA, Sathappa M, Nonato MC, Nguyen KT, Wright SK, Liu DR, Wagner FF, Kaushik VK, Auld DS, Schreiber SL, Minikel EV. Multimodal small-molecule screening for human prion protein binders. J Biol Chem 2020; 295:13516-13531. [PMID: 32723867 PMCID: PMC7521658 DOI: 10.1074/jbc.ra120.014905] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 07/21/2020] [Indexed: 12/16/2022] Open
Abstract
Prion disease is a rapidly progressive neurodegenerative disorder caused by misfolding and aggregation of the prion protein (PrP), and there are currently no therapeutic options. PrP ligands could theoretically antagonize prion formation by protecting the native protein from misfolding or by targeting it for degradation, but no validated small-molecule binders have been discovered to date. We deployed a variety of screening methods in an effort to discover binders of PrP, including 19F-observed and saturation transfer difference (STD) NMR spectroscopy, differential scanning fluorimetry (DSF), DNA-encoded library selection, and in silico screening. A single benzimidazole compound was confirmed in concentration-response, but affinity was very weak (Kd > 1 mm), and it could not be advanced further. The exceptionally low hit rate observed here suggests that PrP is a difficult target for small-molecule binders. Whereas orthogonal binder discovery methods could yield high-affinity compounds, non-small-molecule modalities may offer independent paths forward against prion disease.
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Affiliation(s)
- Andrew G Reidenbach
- Chemical Biology and Therapeutics Science Program, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA
| | - Michael F Mesleh
- Center for the Development of Therapeutics, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA
| | - Dominick Casalena
- Facilitated Access to Screening Technologies (FAST) Lab, Novartis Institutes for Biomedical Research (NIBR), Cambridge, Massachusetts, USA
| | - Sonia M Vallabh
- Chemical Biology and Therapeutics Science Program, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA; Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA; Prion Alliance, Cambridge, Massachusetts, USA; Harvard Medical School, Boston, Massachusetts, USA
| | - Jayme L Dahlin
- Harvard Medical School, Boston, Massachusetts, USA; Department of Pathology, Brigham and Women's Hospital, Boston, Massachusetts, USA
| | - Alison J Leed
- Center for the Development of Therapeutics, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA
| | - Alix I Chan
- Chemical Biology and Therapeutics Science Program, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA
| | - Dmitry L Usanov
- Chemical Biology and Therapeutics Science Program, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA; Center for the Development of Therapeutics, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA
| | - Jenna B Yehl
- Center for the Development of Therapeutics, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA
| | - Christopher T Lemke
- Center for the Development of Therapeutics, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA
| | - Arthur J Campbell
- Center for the Development of Therapeutics, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA
| | - Rishi N Shah
- Undergraduate Research Opportunities Program (UROP), Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Om K Shrestha
- Facilitated Access to Screening Technologies (FAST) Lab, Novartis Institutes for Biomedical Research (NIBR), Cambridge, Massachusetts, USA
| | - Joshua R Sacher
- Center for the Development of Therapeutics, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA
| | - Victor L Rangel
- School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Jamie A Moroco
- Center for the Development of Therapeutics, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA
| | - Murugappan Sathappa
- Center for the Development of Therapeutics, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA
| | - Maria Cristina Nonato
- School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Kong T Nguyen
- Artificial Intelligence Molecular Screen (AIMS) Awards Program, Atomwise, San Francisco, California, USA
| | - S Kirk Wright
- Facilitated Access to Screening Technologies (FAST) Lab, Novartis Institutes for Biomedical Research (NIBR), Cambridge, Massachusetts, USA
| | - David R Liu
- Chemical Biology and Therapeutics Science Program, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA; Merkin Institute of Transformative Technologies in Healthcare, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA; Howard Hughes Medical Institute, Chevy Chase, Maryland, USA; Department of Chemistry & Chemical Biology, Harvard University, Cambridge, Massachusetts, USA
| | - Florence F Wagner
- Center for the Development of Therapeutics, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA; Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA
| | - Virendar K Kaushik
- Center for the Development of Therapeutics, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA
| | - Douglas S Auld
- Facilitated Access to Screening Technologies (FAST) Lab, Novartis Institutes for Biomedical Research (NIBR), Cambridge, Massachusetts, USA
| | - Stuart L Schreiber
- Chemical Biology and Therapeutics Science Program, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA; Department of Chemistry & Chemical Biology, Harvard University, Cambridge, Massachusetts, USA
| | - Eric Vallabh Minikel
- Chemical Biology and Therapeutics Science Program, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA; Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA; Prion Alliance, Cambridge, Massachusetts, USA; Harvard Medical School, Boston, Massachusetts, USA.
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14
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Xu Z, Liu H, Wang S, Zhang Q, Yao X, Zhou S, Liu H. Unraveling the Molecular Mechanism of Prion H2 C-Terminus Misfolding by Metadynamics Simulations. ACS Chem Neurosci 2020; 11:772-782. [PMID: 32023408 DOI: 10.1021/acschemneuro.9b00679] [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] [Indexed: 12/14/2022] Open
Abstract
Conformational transition from the normal cellular form of prion protein (PrPC) to the pathogenic "scrapie" form (PrPSc) is considered to be a key event in the occurrence of prion disease. Additionally, the H2 C-terminus is widely considered to be a vital site for PrP conformational transition, which can be used as an important region to explore the potential mechanism of PrP misfolding. Therefore, to study the misfolding mechanism of PrP, 500 ns well-tempered metadynamics simulations were performed by focusing on the H2 C-terminus of PrP. For comparison, three systems were designed in total, including PrP in neutral and acidic conditions, as well as H187R mutant. The resulting free energy surfaces (FESs) obtained from metadynamics simulations reveal that acidic conditions and H187R mutation can facilitate PrP misfolding by decreasing free energy barriers for conformational transition and forming energy stable conformational states. Further analyses aimed at H2 C-terminus show that due to the increase of positive charge on residue 187 in both acidic and H187R systems, the electrostatic repulsion of residue 187 and R136/R156 increases greatly, which disrupts the electrostatic interaction network around H2 C-terminus and exposes the hydrophobic core to the solvent. Taken together, acidic conditions and H187R mutation can accelerate PrP misfolding mainly by forming more energetically stable metastable conformations with lower free energy barriers, and electrostatic network disruption involving residue 187 drives the initial misfolding of H2 C-terminus. This study provides quantitative insight into the related function of the H2 C-terminus in the PrP misfolding process, which may guide H2 C-terminus mediated drug design in the future.
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Affiliation(s)
- Zerong Xu
- School of Pharmacy, Lanzhou University, Lanzhou 730000, China
| | - Hongli Liu
- School of Pharmacy, Lanzhou University, Lanzhou 730000, China
| | - Shuo Wang
- School of Pharmacy, Lanzhou University, Lanzhou 730000, China
| | - Qianqian Zhang
- School of Pharmacy, Lanzhou University, Lanzhou 730000, China
| | - Xiaojun Yao
- State Key Laboratory of Quality Research in Chinese Medicine, Macau Institute for Applied Research in Medicine and Health, Macau University of Science and Technology, Taipa, Macau, China
| | - Shuangyan Zhou
- Chongqing Key Laboratory of Big Data for Bio Intelligence, Chongqing University of Posts and Telecommunications, Chongqing 400065, China
| | - Huanxiang Liu
- School of Pharmacy, Lanzhou University, Lanzhou 730000, China
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15
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Wille H, Dorosh L, Amidian S, Schmitt-Ulms G, Stepanova M. Combining molecular dynamics simulations and experimental analyses in protein misfolding. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2020; 118:33-110. [PMID: 31928730 DOI: 10.1016/bs.apcsb.2019.10.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The fold of a protein determines its function and its misfolding can result in loss-of-function defects. In addition, for certain proteins their misfolding can lead to gain-of-function toxicities resulting in protein misfolding diseases such as Alzheimer's, Parkinson's, or the prion diseases. In all of these diseases one or more proteins misfold and aggregate into disease-specific assemblies, often in the form of fibrillar amyloid deposits. Most, if not all, protein misfolding diseases share a fundamental molecular mechanism that governs the misfolding and subsequent aggregation. A wide variety of experimental methods have contributed to our knowledge about misfolded protein aggregates, some of which are briefly described in this review. The misfolding mechanism itself is difficult to investigate, as the necessary timescale and resolution of the misfolding events often lie outside of the observable parameter space. Molecular dynamics simulations fill this gap by virtue of their intrinsic, molecular perspective and the step-by-step iterative process that forms the basis of the simulations. This review focuses on molecular dynamics simulations and how they combine with experimental analyses to provide detailed insights into protein misfolding and the ensuing diseases.
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Affiliation(s)
- Holger Wille
- Department of Biochemistry, University of Alberta, Edmonton, Canada; Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Canada; Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Canada
| | - Lyudmyla Dorosh
- Department of Electrical and Computer Engineering, University of Alberta, Edmonton, Canada
| | - Sara Amidian
- Department of Biochemistry, University of Alberta, Edmonton, Canada; Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Canada
| | - Gerold Schmitt-Ulms
- Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Canada
| | - Maria Stepanova
- Department of Electrical and Computer Engineering, University of Alberta, Edmonton, Canada
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16
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Structural insight into conformational change in prion protein by breakage of electrostatic network around H187 due to its protonation. Sci Rep 2019; 9:19305. [PMID: 31848406 PMCID: PMC6917724 DOI: 10.1038/s41598-019-55808-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Accepted: 11/04/2019] [Indexed: 11/10/2022] Open
Abstract
A conformational change from normal prion protein(PrPC) to abnormal prion protein(PrPSC) induces fatal neurodegenerative diseases. Acidic pH is well-known factors involved in the conformational change. Because the protonation of H187 is strongly linked to the change in PrP stability, we examined the charged residues R156, E196, and D202 around H187. Interestingly, there have been reports on pathological mutants, such as H187R, E196A, and D202N. In this study, we focused on how an acidic pH and pathological mutants disrupt this electrostatic network and how this broken network destabilizes PrP structure. To do so, we performed a temperature-based replica-exchange molecular dynamics (T-REMD) simulation using a cumulative 252 μs simulation time. We measured the distance between amino acids comprising four salt bridges (R156–E196/D202 and H187–E196/D202). Our results showed that the spatial configuration of the electrostatic network was significantly altered by an acidic pH and mutations. The structural alteration in the electrostatic network increased the RMSF value around the first helix (H1). Thus, the structural stability of H1, which is anchored to the H2–H3 bundle, was decreased. It induces separation of R156 from the electrostatic network. Analysis of the anchoring energy also shows that two salt-bridges (R156-E196/D202) are critical for PrP stability.
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17
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Lee J, Chang I, Yu W. Atomic insights into the effects of pathological mutants through the disruption of hydrophobic core in the prion protein. Sci Rep 2019; 9:19144. [PMID: 31844149 PMCID: PMC6915724 DOI: 10.1038/s41598-019-55661-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2019] [Accepted: 11/26/2019] [Indexed: 12/11/2022] Open
Abstract
Destabilization of prion protein induces a conformational change from normal prion protein (PrPC) to abnormal prion protein (PrPSC). Hydrophobic interaction is the main driving force for protein folding, and critically affects the stability and solvability. To examine the importance of the hydrophobic core in the PrP, we chose six amino acids (V176, V180, T183, V210, I215, and Y218) that make up the hydrophobic core at the middle of the H2-H3 bundle. A few pathological mutants of these amino acids have been reported, such as V176G, V180I, T183A, V210I, I215V, and Y218N. We focused on how these pathologic mutations affect the hydrophobic core and thermostability of PrP. For this, we ran a temperature-based replica-exchange molecular dynamics (T-REMD) simulation, with a cumulative simulation time of 28 μs, for extensive ensemble sampling. From the T-REMD ensemble, we calculated the protein folding free energy difference between wild-type and mutant PrP using the thermodynamic integration (TI) method. Our results showed that pathological mutants V176G, T183A, I215V, and Y218N decrease the PrP stability. At the atomic level, we examined the change in pair-wise hydrophobic interactions from valine-valine to valine-isoleucine (and vice versa), which is induced by mutation V180I, V210I (I215V) at the 180th-210th (176th-215th) pair. Finally, we investigated the importance of the π-stacking between Y218 and F175.
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Affiliation(s)
- Juhwan Lee
- Center for Proteome Biophysics, DGIST, Daegu, 42988, Korea.
- Department of Emerging Material Sciences, DGIST, Daegu, 42988, Korea.
- Core Protein Resources Center, DGIST, Daegu, 42988, Korea.
- Supercomputing Bigdata Center, DGIST, Daegu, 42988, Korea.
| | - Iksoo Chang
- Center for Proteome Biophysics, DGIST, Daegu, 42988, Korea
- Core Protein Resources Center, DGIST, Daegu, 42988, Korea
- Supercomputing Bigdata Center, DGIST, Daegu, 42988, Korea
- Department of Brain and Cognitive Sciences, DGIST, Daegu, 42988, Korea
| | - Wookyung Yu
- Core Protein Resources Center, DGIST, Daegu, 42988, Korea.
- Supercomputing Bigdata Center, DGIST, Daegu, 42988, Korea.
- Department of Brain and Cognitive Sciences, DGIST, Daegu, 42988, Korea.
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18
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Chandrasekaran P, Santosh Kumar C, Rangachari K, Sekar K. Disassociation of β1-α1-β2 from the α2-α3 domain of prion protein (PrP) is a prerequisite for the conformational conversion of PrPC into PrPSc: Driven by the free energy landscape. Int J Biol Macromol 2019; 136:368-376. [DOI: 10.1016/j.ijbiomac.2019.06.099] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Revised: 05/29/2019] [Accepted: 06/13/2019] [Indexed: 12/16/2022]
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19
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Gharemirshamlu FR, Bamdad K, Naeimi S. Atomic insight into prion disorder: An intricate detail gained by 0.5 μs molecular dynamics simulation of preventive G127V and deleterious D178V mutation in prion protein. J Cell Biochem 2019; 120:14156-14164. [PMID: 30977169 DOI: 10.1002/jcb.28690] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Revised: 02/22/2019] [Accepted: 02/28/2019] [Indexed: 11/10/2022]
Abstract
In this study we are looking into two contradicting mutations found in prion protein (PrP) viz G127V and D178V, that are reportedly protective and pathogenic, respectively. Despite significant advances in comprehension of the role of pathogenic mutations, the role of protective mutation in amyloid fold inhibition still lacks a substantial basis. To understand the structural basis of protective mutation, molecular dynamics simulation coupled with protein-protein docking and molecular mechanics/Poisson-Boltzmann surface area analysis was used to understand the instant structural variability brought about by these mutations alone and in combination on PrP and prion-prion complex. Atomic-scale investigations successfully revealed that the binding pattern of prion-prion varies differentially in protective and pathogenic mutations with secondary structure showing distinct contrasting patterns, which could supposedly be a critical factor for differential prion behavior in protective and pathogenic mutations. Considering the reported role of an amyloid fold in prion-prion binding, the contrasting pattern has given us a lead in comprehending the role of these mutations and has been used in this study to look for small molecules that can inhibit amyloid fold for prion-prion interaction in pathogenic mutant carrying PrP.
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Affiliation(s)
| | - Kourosh Bamdad
- Department of Biology, Payame Noor University, Tehrān, Iran
| | - Sirous Naeimi
- Department of Genetics, Islamic Azad University, Kāzerūn, Iran
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20
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Zhu Y, Guo J, Zhang A, Li L, Liu X, Liu H, Yao X. How graphene affects the misfolding of human prion protein: A combined experimental and molecular dynamics simulation study. ENVIRONMENTAL RESEARCH 2019; 171:1-10. [PMID: 30641367 DOI: 10.1016/j.envres.2018.12.057] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2018] [Revised: 12/15/2018] [Accepted: 12/23/2018] [Indexed: 06/09/2023]
Abstract
As the broad application of graphene in the biomedical field, it is urgent and important to evaluate how the graphene affects the structure and function of the proteins in our body, especially the amyloid-related proteins. Prion protein, as a typical amyloid protein, it misfolding and aggregation will lead to serious prion diseases. To explore if graphene promotes or inhibits the formation of amyloid, here, we combined the experimental and molecular dynamics (MD) simulation methods to study the influence of graphene on the globular domain of prion protein (PrP117-231). The results from fluorescence quenching and circular dichroism spectrum showed that the addition of graphene changed the secondary structure of prion protein largely, mainly reflecting in the reduced α-helix structure and the increased coil structure, indicating graphene may strengthen the misfolding inclination of prion. To further uncover the mechanism of conformational change of prion under the induction of graphene, the all-atoms MD simulations in explicit solvent were performed. Our simulations suggest that prion protein can be quickly and tightly adsorbed onto graphene together with the weak conformational rearrangement and may reorient when approaching the surface. The Van der Waals' force drive the adsorption process. In the induction of graphene, H1 and S2-H2 loop regions of prion become unstable and prion begins to misfold partially. Our work shows that graphene can induce the misfolding of prion protein and may cause the potential risk to biosystems.
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Affiliation(s)
- Yongchang Zhu
- School of Pharmacy, Lanzhou University, Lanzhou 730000, China
| | - Jingjing Guo
- School of Pharmacy, Lanzhou University, Lanzhou 730000, China
| | - Ai Zhang
- School of Pharmacy, Lanzhou University, Lanzhou 730000, China
| | - Lanlan Li
- State Key Laboratory of Applied Organic Chemistry and Department of Chemistry, Lanzhou University, Lanzhou 730000, China
| | - Xuewei Liu
- School of Pharmacy, Lanzhou University, Lanzhou 730000, China
| | - Huanxiang Liu
- School of Pharmacy, Lanzhou University, Lanzhou 730000, China; State Key Laboratory of Applied Organic Chemistry and Department of Chemistry, Lanzhou University, Lanzhou 730000, China.
| | - Xiaojun Yao
- State Key Laboratory of Applied Organic Chemistry and Department of Chemistry, Lanzhou University, Lanzhou 730000, China; State Key Laboratory of Quality Research in Chinese Medicine, Macau Institute for Applied Research in Medicine and Health, Macau University of Science and Technology, Taipa, Macau, China
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21
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Jani V, Sonavane U, Joshi R. Detecting early stage structural changes in wild type, pathogenic and non-pathogenic prion variants using Markov state model. RSC Adv 2019; 9:14567-14579. [PMID: 35519320 PMCID: PMC9064127 DOI: 10.1039/c9ra01507h] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Accepted: 04/28/2019] [Indexed: 12/19/2022] Open
Abstract
The conversion of prion protein from normal to scrapie followed by the aggregation and deposition of this scrapie form leads to various neurodegenerative diseases. A few studies carried out by researchers suggest that E219K prion mutant (glutamate to lysine mutation at residue position 219) is more stable than wild type protein. However a similar point mutation E200K (glutamate to lysine mutation at residue position 200) is pathogenic. In this study we have carried out detailed atomistic simulation of the wild type, pathogenic mutant E200K and E219K mutant which provides more stability. The aim of the study was to detect the early structural changes present in all the three variants which might be responsible for the stability or for their conversion from PrPC to PrPSc. MSM based analyses have been carried out to find out the differences between WT, E200K and E219K systems. Markov state model (MSM) analysis was able to predict the intermediate states which helped to understand the effect of same mutation at two different locations. The MSM analysis was able to show that the extra stability of E219K mutant may be a result of the increase in number of native contacts, strong salt bridges and less random motions. While pathogenicity of E200K mutant can be attributed to loss of some crucial salt-bridge interactions, increased random motions between helix 2 and helix 3. Markov state model to find out the differences between WT, E200K and E219K systems.![]()
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Affiliation(s)
- Vinod Jani
- High Performance Computing-Medical & Bioinformatics Applications Group
- Centre for Development of Advanced Computing (C-DAC)
- Savitribai Phule Pune University Campus
- Pune 411007
- India
| | - Uddhavesh Sonavane
- High Performance Computing-Medical & Bioinformatics Applications Group
- Centre for Development of Advanced Computing (C-DAC)
- Savitribai Phule Pune University Campus
- Pune 411007
- India
| | - Rajendra Joshi
- High Performance Computing-Medical & Bioinformatics Applications Group
- Centre for Development of Advanced Computing (C-DAC)
- Savitribai Phule Pune University Campus
- Pune 411007
- India
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22
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Zhou S, Zhu Y, Yao X, Liu H. Carbon Nanoparticles Inhibit the Aggregation of Prion Protein as Revealed by Experiments and Atomistic Simulations. J Chem Inf Model 2018; 59:1909-1918. [DOI: 10.1021/acs.jcim.8b00725] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Shuangyan Zhou
- School of Pharmacy, Lanzhou University, Lanzhou 730000, China
- Chongqing Key Laboratory on Big Data for Bio Intelligence, Chongqing University of Posts and Telecommunications, Chongqing 400065, China
| | - Yongchang Zhu
- School of Pharmacy, Lanzhou University, Lanzhou 730000, China
- State Key Laboratory of Applied Organic Chemistry and Department of Chemistry, Lanzhou University, Lanzhou 730000, China
| | - Xiaojun Yao
- State Key Laboratory of Applied Organic Chemistry and Department of Chemistry, Lanzhou University, Lanzhou 730000, China
- State Key Laboratory of Quality Research in Chinese Medicine, Macau Institute for Applied Research in Medicine and Health, Macau University of Science and Technology, Taipa, Macau, China
| | - Huanxiang Liu
- School of Pharmacy, Lanzhou University, Lanzhou 730000, China
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23
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Structural Determinants of the Prion Protein N-Terminus and Its Adducts with Copper Ions. Int J Mol Sci 2018; 20:ijms20010018. [PMID: 30577569 PMCID: PMC6337743 DOI: 10.3390/ijms20010018] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 12/17/2018] [Accepted: 12/18/2018] [Indexed: 12/24/2022] Open
Abstract
The N-terminus of the prion protein is a large intrinsically disordered region encompassing approximately 125 amino acids. In this paper, we review its structural and functional properties, with a particular emphasis on its binding to copper ions. The latter is exploited by the region’s conformational flexibility to yield a variety of biological functions. Disease-linked mutations and proteolytic processing of the protein can impact its copper-binding properties, with important structural and functional implications, both in health and disease progression.
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24
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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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25
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Zheng Z, Zhang M, Wang Y, Ma R, Guo C, Feng L, Wu J, Yao H, Lin D. Structural basis for the complete resistance of the human prion protein mutant G127V to prion disease. Sci Rep 2018; 8:13211. [PMID: 30181558 PMCID: PMC6123418 DOI: 10.1038/s41598-018-31394-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Accepted: 08/08/2018] [Indexed: 12/20/2022] Open
Abstract
Prion diseases are caused by the propagation of misfolded cellular prion proteins (PrPs). A completely prion disease-resistant genotype, V127M129, has been identified in Papua New Guinea and verified in transgenic mice. To disclose the structural basis of the disease-resistant effect of the G127V mutant, we determined and compared the structural and dynamic features of the G127V-mutated human PrP (residues 91-231) and the wild-type PrP in solution. HuPrP(G127V) contains α1, α2 and α3 helices and a stretch-strand (SS) pattern comprising residues Tyr128-Gly131 (SS1) and Val161-Arg164 (SS2), with extending atomic distances between the SS1 and SS2 strands, and a structural rearrangement of the Tyr128 side chain due to steric hindrance of the larger hydrophobic side chain of Val127. The extended α1 helix gets closer to the α2 and α3 helices. NMR dynamics analysis revealed that Tyr128, Gly131 and Tyr163 underwent significant conformational exchanges. Molecular dynamics simulations suggest that HuPrP(G127V) prevents the formation of stable β-sheets and dimers. Unique structural and dynamic features potentially inhibit the conformational conversion of the G127V mutant. This work is beneficial for understanding the molecular mechanisms underlying the complete resistance of the G127V mutant to prion disease and for developing new therapeutics for prion disease.
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Affiliation(s)
- Zhen Zheng
- MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, Key Laboratory of Chemical Biology of Fujian Province, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, China
| | - Meilan Zhang
- MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, Key Laboratory of Chemical Biology of Fujian Province, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, China
| | - Yongheng Wang
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, 510006, China
| | - Rongsheng Ma
- School of Life Sciences, University of Science and Technology of China, Hefei, 230026, China
| | - Chenyun Guo
- MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, Key Laboratory of Chemical Biology of Fujian Province, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, China
| | - Liubin Feng
- MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, Key Laboratory of Chemical Biology of Fujian Province, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, China
| | - Jihui Wu
- School of Life Sciences, University of Science and Technology of China, Hefei, 230026, China
| | - Hongwei Yao
- MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, Key Laboratory of Chemical Biology of Fujian Province, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, China
| | - Donghai Lin
- MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, Key Laboratory of Chemical Biology of Fujian Province, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, China.
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Lima AN, de Oliveira RJ, Braz ASK, de Souza Costa MG, Perahia D, Scott LPB. Effects of pH and aggregation in the human prion conversion into scrapie form: a study using molecular dynamics with excited normal modes. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2018; 47:583-590. [PMID: 29546436 DOI: 10.1007/s00249-018-1292-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Revised: 02/19/2018] [Accepted: 03/12/2018] [Indexed: 12/20/2022]
Abstract
There are two different prion conformations: (1) the cellular natural (PrPC) and (2) the scrapie (PrPSc), an infectious form that tends to aggregate under specific conditions. PrPC and PrPSc are widely different regarding secondary and tertiary structures. PrPSc contains more and longer β-strands compared to PrPC. The lack of solved PrPSc structures precludes a proper understanding of the mechanisms related to the transition between cellular and scrapie forms, as well as the aggregation process. In order to investigate the conformational transition between PrPC and PrPSc, we applied MDeNM (molecular dynamics with excited normal modes), an enhanced sampling simulation technique that has been recently developed to probe large structural changes. These simulations yielded new structural rearrangements of the cellular prion that would have been difficult to obtain with standard MD simulations. We observed an increase in β-sheet formation under low pH (≤ 4) and upon oligomerization, whose relevance was discussed on the basis of the energy landscape theory for protein folding. The characterization of intermediate structures corresponding to transition states allowed us to propose a conversion model from the cellular to the scrapie prion, which possibly ignites the fibril formation. This model can assist the design of new drugs to prevent neurological disorders related to the prion aggregation mechanism.
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Affiliation(s)
- Angelica Nakagawa Lima
- Laboratório de Biologia Computacional e Bioinformática, Universidade Federal do ABC, Santo André, SP, Brazil
- Laboratório de Biofísica Teórica, Departamento de Física, Instituto de Ciências Exatas, Naturais e Educação, Universidade Federal do Triângulo Mineiro, Uberaba, MG, Brazil
| | - Ronaldo Junio de Oliveira
- Laboratório de Biofísica Teórica, Departamento de Física, Instituto de Ciências Exatas, Naturais e Educação, Universidade Federal do Triângulo Mineiro, Uberaba, MG, Brazil
| | - Antônio Sérgio Kimus Braz
- Laboratório de Biologia Computacional e Bioinformática, Universidade Federal do ABC, Santo André, SP, Brazil
| | | | - David Perahia
- Laboratorie de Biologie et Pharmacologie Appliquée, Ecole Normale Supérieure Paris-Saclay, Cachan, France
| | - Luis Paulo Barbour Scott
- Laboratório de Biologia Computacional e Bioinformática, Universidade Federal do ABC, Santo André, SP, Brazil.
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27
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Bhattacharya S, Xu L, Thompson D. Revisiting the earliest signatures of amyloidogenesis: Roadmaps emerging from computational modeling and experiment. WILEY INTERDISCIPLINARY REVIEWS-COMPUTATIONAL MOLECULAR SCIENCE 2018. [DOI: 10.1002/wcms.1359] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- Shayon Bhattacharya
- Department of Physics, Bernal InstituteUniversity of LimerickLimerickIreland
| | - Liang Xu
- Department of Physics, Bernal InstituteUniversity of LimerickLimerickIreland
| | - Damien Thompson
- Department of Physics, Bernal InstituteUniversity of LimerickLimerickIreland
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28
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Kovač V, Čurin Šerbec V. Prion Proteins Without the Glycophosphatidylinositol Anchor: Potential Biomarkers in Neurodegenerative Diseases. Biomark Insights 2018; 13:1177271918756648. [PMID: 29449775 PMCID: PMC5808966 DOI: 10.1177/1177271918756648] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Accepted: 11/23/2017] [Indexed: 01/17/2023] Open
Abstract
Prion protein (PrP) is a biomolecule that is involved in neuronal signaling, myelinization, and the development of neurodegenerative diseases. In the cell, PrP is shed by the ADAM10 protease. This process generates PrP molecules that lack glycophosphatidylinositol anchor, and these molecules incorporate into toxic aggregates and neutralize toxic oligomers. Due to this dual role, these molecules are important biomarkers for neurodegenerative diseases. In this review, we present shed PrP as a potential biomarker, with a focus on PrP226*, which may be the main biomarker for predicting neurodegenerative diseases in humans.
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Affiliation(s)
- Valerija Kovač
- Department for the Production of Diagnostic Reagents and Research, Blood Transfusion Centre of Slovenia, Ljubljana, Slovenia
| | - Vladka Čurin Šerbec
- Department for the Production of Diagnostic Reagents and Research, Blood Transfusion Centre of Slovenia, Ljubljana, Slovenia
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29
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The function of the cellular prion protein in health and disease. Acta Neuropathol 2018; 135:159-178. [PMID: 29151170 DOI: 10.1007/s00401-017-1790-y] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Revised: 11/13/2017] [Accepted: 11/14/2017] [Indexed: 12/11/2022]
Abstract
The essential role of the cellular prion protein (PrPC) in prion disorders such as Creutzfeldt-Jakob disease is well documented. Moreover, evidence is accumulating that PrPC may act as a receptor for protein aggregates and transduce neurotoxic signals in more common neurodegenerative disorders, such as Alzheimer's disease. Although the pathological roles of PrPC have been thoroughly characterized, a general consensus on its physiological function within the brain has not yet been established. Knockout studies in various organisms, ranging from zebrafish to mice, have implicated PrPC in a diverse range of nervous system-related activities that include a key role in the maintenance of peripheral nerve myelination as well as a general ability to protect against neurotoxic stimuli. Thus, the function of PrPC may be multifaceted, with different cell types taking advantage of unique aspects of its biology. Deciphering the cellular function(s) of PrPC and the consequences of its absence is not simply an academic curiosity, since lowering PrPC levels in the brain is predicted to be a powerful therapeutic strategy for the treatment of prion disease. In this review, we outline the various approaches that have been employed in an effort to uncover the physiological and pathological functions of PrPC. While these studies have revealed important clues about the biology of the prion protein, the precise reason for PrPC's existence remains enigmatic.
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30
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Mackenzie HW, Hansen DF. A 13C-detected 15N double-quantum NMR experiment to probe arginine side-chain guanidinium 15N η chemical shifts. JOURNAL OF BIOMOLECULAR NMR 2017; 69:123-132. [PMID: 29127559 PMCID: PMC5711973 DOI: 10.1007/s10858-017-0137-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Accepted: 09/25/2017] [Indexed: 05/25/2023]
Abstract
Arginine side-chains are often key for enzyme catalysis, protein-ligand and protein-protein interactions. The importance of arginine stems from the ability of the terminal guanidinium group to form many key interactions, such as hydrogen bonds and salt bridges, as well as its perpetual positive charge. We present here an arginine 13Cζ-detected NMR experiment in which a double-quantum coherence involving the two 15Nη nuclei is evolved during the indirect chemical shift evolution period. As the precession frequency of the double-quantum coherence is insensitive to exchange of the two 15Nη; this new approach is shown to eliminate the previously deleterious line broadenings of 15Nη resonances caused by the partially restricted rotation about the Cζ-Nε bond. Consequently, sharp and well-resolved 15Nη resonances can be observed. The utility of the presented method is demonstrated on the L99A mutant of the 19 kDa protein T4 lysozyme, where the measurement of small chemical shift perturbations, such as one-bond deuterium isotope shifts, of the arginine amine 15Nη nuclei becomes possible using the double-quantum experiment.
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Affiliation(s)
- Harold W Mackenzie
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, London, WC1E 6BT, UK
| | - D Flemming Hansen
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, London, WC1E 6BT, UK.
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31
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Ke PC, Sani MA, Ding F, Kakinen A, Javed I, Separovic F, Davis TP, Mezzenga R. Implications of peptide assemblies in amyloid diseases. Chem Soc Rev 2017; 46:6492-6531. [PMID: 28702523 PMCID: PMC5902192 DOI: 10.1039/c7cs00372b] [Citation(s) in RCA: 239] [Impact Index Per Article: 34.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Neurodegenerative disorders and type 2 diabetes are global epidemics compromising the quality of life of millions worldwide, with profound social and economic implications. Despite the significant differences in pathology - much of which are poorly understood - these diseases are commonly characterized by the presence of cross-β amyloid fibrils as well as the loss of neuronal or pancreatic β-cells. In this review, we document research progress on the molecular and mesoscopic self-assembly of amyloid-beta, alpha synuclein, human islet amyloid polypeptide and prions, the peptides and proteins associated with Alzheimer's, Parkinson's, type 2 diabetes and prion diseases. In addition, we discuss the toxicities of these amyloid proteins based on their self-assembly as well as their interactions with membranes, metal ions, small molecules and engineered nanoparticles. Through this presentation we show the remarkable similarities and differences in the structural transitions of the amyloid proteins through primary and secondary nucleation, the common evolution from disordered monomers to alpha-helices and then to β-sheets when the proteins encounter the cell membrane, and, the consensus (with a few exceptions) that off-pathway oligomers, rather than amyloid fibrils, are the toxic species regardless of the pathogenic protein sequence or physicochemical properties. In addition, we highlight the crucial role of molecular self-assembly in eliciting the biological and pathological consequences of the amyloid proteins within the context of their cellular environments and their spreading between cells and organs. Exploiting such structure-function-toxicity relationship may prove pivotal for the detection and mitigation of amyloid diseases.
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Affiliation(s)
- Pu Chun Ke
- ARC Center of Excellence in Convergent Bio-Nano Science and Technology, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
| | - Marc-Antonie Sani
- School of Chemistry, Bio21 Institute, The University of Melbourne, 30 Flemington Rd, Parkville, VIC 3010, Australia
| | - Feng Ding
- Department of Physics and Astronomy, Clemson University, Clemson, SC 29634, United States
| | - Aleksandr Kakinen
- ARC Center of Excellence in Convergent Bio-Nano Science and Technology, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
| | - Ibrahim Javed
- ARC Center of Excellence in Convergent Bio-Nano Science and Technology, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
| | - Frances Separovic
- School of Chemistry, Bio21 Institute, The University of Melbourne, 30 Flemington Rd, Parkville, VIC 3010, Australia
| | - Thomas P. Davis
- ARC Center of Excellence in Convergent Bio-Nano Science and Technology, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
- Department of Chemistry, University of Warwick, Gibbet Hill, Coventry, CV4 7AL, United Kingdom
| | - Raffaele Mezzenga
- ETH Zurich, Department of Health Science & Technology, Schmelzbergstrasse 9, LFO, E23, 8092 Zurich, Switzerland
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32
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Bamdad K. Sequence-dependent dynamical instability of the human prion protein: a comparative simulation study. J Biomol Struct Dyn 2017; 36:3023-3033. [PMID: 28868991 DOI: 10.1080/07391102.2017.1375430] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The present study aimed to explore the most probable regions of the human prion protein backbone for which the initial steps of conformational transitions as a result of intrinsic and extrinsic perturbing factors on the protein structure can be assigned. A total of 0.3-μs molecular dynamics simulations on several analog structures of the protein have been performed. To mimic the impact of the extrinsic and intrinsic destructive parameters on the dynamical characteristics of the protein, mild acidic conditions and R208H mutation have been simulated. The findings indicated that distribution of conformational flexibilities along the protein chain was almost independent of the induced perturbing factors, and was mostly centralized on certain distinct parts of the structure comprising residues 132-145 and 187-203. Analyses also revealed that the segment comprising residues 187-203 may be considered as a peptide sequence, possessing high potential to start the initial steps of conformational rearrangements due to the induced physicochemical alterations. Sequence alignment and molecular dynamics data also revealed that segment 178-203 prefers to accommodate in extended structures rather than α-helices. Region 178-203 may be considered as a peptide switch capable of initiating the conformational transitions due to the introduced modifications and perturbing parameters.
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Affiliation(s)
- Kourosh Bamdad
- a Department of Biology, Faculty of Science , Payame Noor University (PNU) , 19395-3697 , Iran
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33
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Li Y, Kang C. Solution NMR Spectroscopy in Target-Based Drug Discovery. Molecules 2017; 22:E1399. [PMID: 28832542 PMCID: PMC6151424 DOI: 10.3390/molecules22091399] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Revised: 08/18/2017] [Accepted: 08/18/2017] [Indexed: 12/14/2022] Open
Abstract
Solution NMR spectroscopy is a powerful tool to study protein structures and dynamics under physiological conditions. This technique is particularly useful in target-based drug discovery projects as it provides protein-ligand binding information in solution. Accumulated studies have shown that NMR will play more and more important roles in multiple steps of the drug discovery process. In a fragment-based drug discovery process, ligand-observed and protein-observed NMR spectroscopy can be applied to screen fragments with low binding affinities. The screened fragments can be further optimized into drug-like molecules. In combination with other biophysical techniques, NMR will guide structure-based drug discovery. In this review, we describe the possible roles of NMR spectroscopy in drug discovery. We also illustrate the challenges encountered in the drug discovery process. We include several examples demonstrating the roles of NMR in target-based drug discoveries such as hit identification, ranking ligand binding affinities, and mapping the ligand binding site. We also speculate the possible roles of NMR in target engagement based on recent processes in in-cell NMR spectroscopy.
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Affiliation(s)
- Yan Li
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, Nanos, #03-01, Singapore 138669, Singapore.
| | - Congbao Kang
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, Nanos, #03-01, Singapore 138669, Singapore.
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34
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Sengupta I, Bhate SH, Das R, Udgaonkar JB. Salt-Mediated Oligomerization of the Mouse Prion Protein Monitored by Real-Time NMR. J Mol Biol 2017; 429:1852-1872. [DOI: 10.1016/j.jmb.2017.05.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Revised: 05/05/2017] [Accepted: 05/07/2017] [Indexed: 12/11/2022]
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35
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Redaelli V, Tagliavini F, Moda F. Clinical features, pathophysiology and management of fatal familial insomnia. Expert Opin Orphan Drugs 2017. [DOI: 10.1080/21678707.2017.1311251] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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36
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Paz SA, Vanden-Eijnden E, Abrams CF. Polymorphism at 129 dictates metastable conformations of the human prion protein N-terminal β-sheet. Chem Sci 2017; 8:1225-1232. [PMID: 28451263 PMCID: PMC5369536 DOI: 10.1039/c6sc03275c] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2016] [Accepted: 09/30/2016] [Indexed: 12/16/2022] Open
Abstract
We study the thermodynamic stability of the native state of the human prion protein using a new free-energy method, replica-exchange on-the-fly parameterization. This method is designed to overcome hidden-variable sampling limitations to yield nearly error-free free-energy profiles along a conformational coordinate. We confirm that all four (M129V, D178N) polymorphs have a ground-state conformation with three intact β-sheet hydrogen bonds. Additionally, they are observed to have distinct metastabilities determined by the side-chain at position 129. We rationalize these findings with reference to the prion "strain" hypothesis, which links the variety of transmissible spongiform encephalopathy phenotypes to conformationally distinct infectious prion forms and classifies distinct phenotypes of sporadic Creutzfeldt-Jakob disease based solely on the 129 polymorphism. Because such metastable structures are not easily observed in structural experiments, our approach could potentially provide new insights into the conformational origins of prion diseases and other pathologies arising from protein misfolding and aggregation.
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Affiliation(s)
- S Alexis Paz
- Department of Chemical and Biological Engineering , Drexel University , Philadelphia , PA 19104 , USA .
| | - Eric Vanden-Eijnden
- Courant Institute of Mathematical Sciences , New York University , New York , NY 10012 , USA
| | - Cameron F Abrams
- Department of Chemical and Biological Engineering , Drexel University , Philadelphia , PA 19104 , USA .
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37
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Singh RK, Chamachi NG, Chakrabarty S, Mukherjee A. Mechanism of Unfolding of Human Prion Protein. J Phys Chem B 2017; 121:550-564. [PMID: 28030950 DOI: 10.1021/acs.jpcb.6b11416] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Misfolding and aggregation of prion proteins are associated with several neurodegenerative diseases. Therefore, understanding the mechanism of the misfolding process is of enormous interest in the scientific community. It has been speculated and widely discussed that the native cellular prion protein (PrPC) form needs to undergo substantial unfolding to a more stable PrPC* state, which may further oligomerize into the toxic scrapie (PrPSc) form. Here, we have studied the mechanism of the unfolding of the human prion protein (huPrP) using a set of extensive well-tempered metadynamics simulations. Through multiple microsecond-long metadynamics simulations, we find several possible unfolding pathways. We show that each pathway leads to an unfolded state of lower free energy than the native state. Thus, our study may point to the signature of a PrPC* form that corresponds to a global minimum on the conformational free-energy landscape. Moreover, we find that these global minima states do not involve an increased β-sheet content, as was assumed to be a signature of PrPSc formation in previous simulation studies. We have further analyzed the origin of metastability of the PrPC form through free-energy surfaces of the chopped helical segments to show that the helices, particularly H2 and H3 of the prion protein, have the tendency to form either a random coil or a β-structure. Therefore, the secondary structural elements of the prion protein are only weakly stabilized by tertiary contacts and solvation forces so that relatively weak perturbations induced by temperature, pressure, pH, and so forth can lead to substantial unfolding with characteristics of intrinsically disordered proteins.
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Affiliation(s)
- Reman K Singh
- Department of Chemistry, Indian Institute of Science Education and Research , Pune 411008, Maharashtra, India
| | - Neharika G Chamachi
- Physical and Materials Chemistry Division, CSIR-National Chemical Laboratory , Pune 411008, Maharashtra, India
| | - Suman Chakrabarty
- Physical and Materials Chemistry Division, CSIR-National Chemical Laboratory , Pune 411008, Maharashtra, India
| | - Arnab Mukherjee
- Department of Chemistry, Indian Institute of Science Education and Research , Pune 411008, Maharashtra, India
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38
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Understanding the Effect of Disease-Related Mutations on Human Prion Protein Structure: Insights From NMR Spectroscopy. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2017; 150:83-103. [DOI: 10.1016/bs.pmbts.2017.06.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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39
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Structural Modeling of Human Prion Protein's Point Mutations. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2017; 150:105-122. [DOI: 10.1016/bs.pmbts.2017.07.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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40
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Wu EL, Qi Y, Park S, Mallajosyula SS, MacKerell AD, Klauda JB, Im W. Insight into Early-Stage Unfolding of GPI-Anchored Human Prion Protein. Biophys J 2016; 109:2090-100. [PMID: 26588568 DOI: 10.1016/j.bpj.2015.10.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Revised: 10/04/2015] [Accepted: 10/08/2015] [Indexed: 11/29/2022] Open
Abstract
Prion diseases are fatal neurodegenerative disorders, which are characterized by the accumulation of misfolded prion protein (PrPSc) converted from a normal host cellular prion protein (PrPC). Experimental studies suggest that PrPC is enriched with α-helical structure, whereas PrPSc contains a high proportion of β-sheet. In this study, we report the impact of N-glycosylation and the membrane on the secondary structure stability utilizing extensive microsecond molecular dynamics simulations. Our results reveal that the HB (residues 173 to 194) C-terminal fragment undergoes conformational changes and helix unfolding in the absence of membrane environments because of the competition between protein backbone intramolecular and protein-water intermolecular hydrogen bonds as well as its intrinsic instability originated from the amino acid sequence. This initiation of the unfolding process of PrPC leads to a subsequent increase in the length of the HB-HC loop (residues 195 to 199) that may trigger larger rigid body motions or further unfolding around this region. Continuous interactions between prion protein and the membrane not only constrain the protein conformation but also decrease the solvent accessibility of the backbone atoms, thereby stabilizing the secondary structure, which is enhanced by N-glycosylation via additional interactions between the N-glycans and the membrane surface.
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Affiliation(s)
- Emilia L Wu
- Department of Molecular Biosciences and Center for Bioinformatics, The University of Kansas, Lawrence, Kansas
| | - Yifei Qi
- Department of Molecular Biosciences and Center for Bioinformatics, The University of Kansas, Lawrence, Kansas
| | - Soohyung Park
- Department of Molecular Biosciences and Center for Bioinformatics, The University of Kansas, Lawrence, Kansas
| | - Sairam S Mallajosyula
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, Baltimore, Maryland; Department of Chemistry, Indian Institute of Technology Gandhinagar, Chandkheda, Ahmedabad, Gujarat, India
| | - Alexander D MacKerell
- Department of Chemistry, Indian Institute of Technology Gandhinagar, Chandkheda, Ahmedabad, Gujarat, India
| | - Jeffery B Klauda
- Department of Chemical and Biomolecular Engineering and the Biophysics Program, The University of Maryland, College Park, Maryland
| | - Wonpil Im
- Department of Molecular Biosciences and Center for Bioinformatics, The University of Kansas, Lawrence, Kansas.
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41
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Inayathullah M, Rajadas J. Conformational dynamics of a hydrophobic prion fragment (113-127) in different pH and osmolyte solutions. Neuropeptides 2016; 57:9-14. [PMID: 26919915 DOI: 10.1016/j.npep.2016.02.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/22/2015] [Revised: 02/09/2016] [Accepted: 02/14/2016] [Indexed: 01/17/2023]
Abstract
Prion diseases are characterized by a conformational change in prion protein from its native state into beta-sheet rich aggregates that are neurotoxic. The central domain that contain a highly conserved hydrophobic region of the protein play an important role in the toxicity. The conformation of the proteins is largely influenced by various solvent environments. Here we report results of study of hydrophobic prion fragment peptide PrP(113-127) under different pH and osmolytes solution conditions. The secondary structure and the folding of PrP(113-127) was determined using circular dichroism and fluorescence spectroscopic methods. The results indicate that PrP(113-127) adopts a random coil conformation in aqueous buffer at neutral pH and that converted into beta sheet on aging. Even though the initial random coil conformation was similar in different pH conditions, the acidic as well as basic pH conditions delays the conformational transition to beta sheet. FRET results indicate that the distance between N and C-terminal regions increased on aging due to unfolding by self-assembly of the peptide into an organized beta sheet structure. Presence of osmolytes, prevented or decelerated the aggregation process of PrP(113-127) peptide.
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Affiliation(s)
- Mohammed Inayathullah
- Biomaterials and Advanced Drug Delivery Laboratory, School of Medicine, Stanford University, Palo Alto, CA 94304, USA; Bioorganic and Neurochemistry Laboratory, Central Leather Research Institute, Adyar, Chennai, Tamil Nadu 600020, India; Cardiovascular Pharmacology Division, Cardiovascular Institute, School of Medicine, Stanford University, Stanford, CA 94305, USA
| | - Jayakumar Rajadas
- Biomaterials and Advanced Drug Delivery Laboratory, School of Medicine, Stanford University, Palo Alto, CA 94304, USA; Cardiovascular Pharmacology Division, Cardiovascular Institute, School of Medicine, Stanford University, Stanford, CA 94305, USA.
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42
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Borgohain G, Dan N, Paul S. Use of molecular dynamics simulation to explore structural facets of human prion protein with pathogenic mutations. Biophys Chem 2016; 213:32-9. [DOI: 10.1016/j.bpc.2016.03.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2015] [Accepted: 03/17/2016] [Indexed: 10/22/2022]
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Protective V127 prion variant prevents prion disease by interrupting the formation of dimer and fibril from molecular dynamics simulations. Sci Rep 2016; 6:21804. [PMID: 26906032 PMCID: PMC4764842 DOI: 10.1038/srep21804] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Accepted: 02/01/2016] [Indexed: 12/12/2022] Open
Abstract
Recent studies uncovered a novel protective prion protein variant: V127 variant, which was reported intrinsically resistant to prion conversion and propagation. However, the structural basis of its protective effect is still unknown. To uncover the origin of the protective role of V127 variant, molecular dynamics simulations were performed to explore the influence of G127V mutation on two key processes of prion propagation: dimerization and fibril formation. The simulation results indicate V127 variant is unfavorable to form dimer by reducing the main-chain H-bond interactions. The simulations of formed fibrils consisting of β1 strand prove V127 variant will make the formed fibril become unstable and disorder. The weaker interaction energies between layers and reduced H-bonds number for V127 variant reveal this mutation is unfavorable to the formation of stable fibril. Consequently, we find V127 variant is not only unfavorable to the formation of dimer but also unfavorable to the formation of stable core and fibril, which can explain the mechanism on the protective role of V127 variant from the molecular level. Our findings can deepen the understanding of prion disease and may guide the design of peptide mimetics or small molecule to mimic the protective effect of V127 variant.
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Menon S, Sengupta N. Perturbations in inter-domain associations may trigger the onset of pathogenic transformations in PrP(C): insights from atomistic simulations. MOLECULAR BIOSYSTEMS 2016; 11:1443-53. [PMID: 25855580 DOI: 10.1039/c4mb00689e] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Conversion of the predominantly α-helical cellular prion protein (PrP(C)) to the misfolded β-sheet enriched Scrapie form (PrP(Sc)) is a critical event in prion pathogenesis. However, the conformational triggers that lead to the isoform conversion (PrP(C) to PrP(Sc)) remain obscure, and conjectures about the role of unusually hydrophilic, short helix H1 of the C-terminal globular domain in the transition are varied. Helix H1 is anchored to helix H3 via a few stabilizing polar interactions. We have employed fully atomistic molecular dynamics simulations to study the effects triggered by a minor perturbation in the network of these non-bonded interactions in PrP(C). The elimination of just one of the key H1-H3 hydrogen bonds led to a cascade of conformational changes that are consistent with those observed in partially unfolded intermediates of PrP(C), with pathogenic mutations and in low pH environments. Our analyses reveal that the perturbation results in the enhanced conformational flexibility of the protein. The resultant enhancement in the dynamics leads to overall increased solvent exposure of the hydrophobic core residues and concomitant disruption of the H1-H3 inter-domain salt bridge network. This study lends credence to the hypothesis that perturbing the cooperativity of the stabilizing interactions in the PrP(C) globular domain can critically affect its dynamics and may lead to structural transitions of pathological relevance.
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Affiliation(s)
- Sneha Menon
- Physical Chemistry Division, CSIR-National Chemical Laboratory, Pune 411008, India.
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Chandrasekaran P, Rajasekaran R. Detailed computational analysis revealed mutation V210I on PrP induced conformational conversion on β2–α2 loop and α2–α3. MOLECULAR BIOSYSTEMS 2016; 12:3223-33. [DOI: 10.1039/c6mb00342g] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The development of fatal transmissible spongiform encephalopathies (TSE) is associated with the conformational conversion of the normal cellular prion protein, PrPC, into its pathogenic isoform, PrPSc.
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Affiliation(s)
- P. Chandrasekaran
- Computational Biology Lab
- Department of Biotechnology
- School of Biosciences and Technology
- VIT University
- Vellore 632 014
| | - R. Rajasekaran
- Computational Biology Lab
- Department of Biotechnology
- School of Biosciences and Technology
- VIT University
- Vellore 632 014
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Tao W, Yoon G, Cao P, Eom K, Park HS. β-sheet-like formation during the mechanical unfolding of prion protein. J Chem Phys 2015; 143:125101. [DOI: 10.1063/1.4931819] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Affiliation(s)
- Weiwei Tao
- Department of Mechanical Engineering, Boston University, Boston, Massachusetts 02215, USA
| | - Gwonchan Yoon
- Department of Mechanical Engineering, Boston University, Boston, Massachusetts 02215, USA
- Department of Mechanical Engineering, Korea University, Seoul 136-701, South Korea
| | - Penghui Cao
- Department of Mechanical Engineering, Boston University, Boston, Massachusetts 02215, USA
| | - Kilho Eom
- Biomechanics Laboratory, College of Sport Science, Sungkyunkwan University, Suwon 16419, South Korea
| | - Harold S. Park
- Department of Mechanical Engineering, Boston University, Boston, Massachusetts 02215, USA
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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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Moulick R, Das R, Udgaonkar JB. Partially Unfolded Forms of the Prion Protein Populated under Misfolding-promoting Conditions: CHARACTERIZATION BY HYDROGEN EXCHANGE MASS SPECTROMETRY AND NMR. J Biol Chem 2015; 290:25227-40. [PMID: 26306043 DOI: 10.1074/jbc.m115.677575] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Indexed: 12/16/2022] Open
Abstract
The susceptibility of the cellular prion protein (PrP(C)) to convert to an alternative misfolded conformation (PrP(Sc)), which is the key event in the pathogenesis of prion diseases, is indicative of a conformationally flexible native (N) state. In the present study, hydrogen-deuterium exchange (HDX) in conjunction with mass spectrometry and nuclear magnetic resonance spectroscopy were used for the structural and energetic characterization of the N state of the full-length mouse prion protein, moPrP(23-231), under conditions that favor misfolding. The kinetics of HDX of 34 backbone amide hydrogens in the N state were determined at pH 4. In contrast to the results of previous HDX studies on the human and Syrian hamster prion proteins at a higher pH, various segments of moPrP were found to undergo different extents of subglobal unfolding events at pH 4, a pH at which the protein is known to be primed to misfold to a β-rich conformation. No residual structure around the disulfide bond was observed for the unfolded state at pH 4. The N state of the prion protein was observed to be at equilibrium with at least two partially unfolded forms (PUFs). These PUFs, which are accessed by stochastic fluctuations of the N state, have altered surface area exposure relative to the N state. One of these PUFs resembles a conformation previously implicated to be an initial intermediate in the conversion of monomeric protein into misfolded oligomer at pH 4.
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Affiliation(s)
- Roumita Moulick
- From the National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bengaluru 560065, India
| | - Ranabir Das
- From the National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bengaluru 560065, India
| | - Jayant B Udgaonkar
- From the National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bengaluru 560065, India
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Cheng CJ, Daggett V. Different misfolding mechanisms converge on common conformational changes: human prion protein pathogenic mutants Y218N and E196K. Prion 2015; 8:125-35. [PMID: 24509603 DOI: 10.4161/pri.27807] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Prion diseases are caused by misfolding and aggregation of the prion protein (PrP). Pathogenic mutations such as Y218N and E196K are known to cause Gerstmann-Sträussler-Scheinker syndrome and Creutzfeldt-Jakob disease, respectively. Here we describe molecular dynamics simulations of these mutant proteins to better characterize the detailed conformational effects of these sequence substitutions. Our results indicate that the mutations disrupt the wild-type native PrP(C) structure and cause misfolding. Y218N reduced hydrophobic packing around the X-loop (residues 165-171), and E196K abolished an important wild-type salt bridge. While differences in the mutation site led PrP mutants to misfold along different pathways, we observed multiple traits of misfolding that were common to both mutants. Common traits of misfolding included: 1) detachment of the short helix (HA) from the PrP core; 2) exposure of side chain F198; and 3) formation of a nonnative strand at the N-terminus. The effect of the E196K mutation directly abolished the wild-type salt bridge E196-R156, which further destabilized the F198 hydrophobic pocket and HA. The Y218N mutation propagated its effect by increasing the HB-HC interhelical angle, which in turn disrupted the packing around F198. Furthermore, a nonnative contact formed between E221 and S132 on the S1-HA loop, which offered a direct mechanism for disrupting the hydrophobic packing between the S1-HA loop and HC. While there were common misfolding features shared between Y218N and E196K, the differences in the orientation of HB and HC and the X-loop conformation might provide a structural basis for identifying different prion strains.
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Hadži S, Ondračka A, Jerala R, Hafner‐Bratkovič I. Pathological mutations H187R and E196K facilitate subdomain separation and prion protein conversion by destabilization of the native structure. FASEB J 2014; 29:882-93. [DOI: 10.1096/fj.14-255646] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- San Hadži
- Department of BiotechnologyNational Institute of ChemistryLjubljanaSlovenia
| | - Andrej Ondračka
- Department of BiotechnologyNational Institute of ChemistryLjubljanaSlovenia
| | - Roman Jerala
- Department of BiotechnologyNational Institute of ChemistryLjubljanaSlovenia
- EN‐FIST Centre of ExcellenceLjubljanaSlovenia
| | - Iva Hafner‐Bratkovič
- Department of BiotechnologyNational Institute of ChemistryLjubljanaSlovenia
- EN‐FIST Centre of ExcellenceLjubljanaSlovenia
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