101
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Leri M, Bemporad F, Oropesa-Nuñez R, Canale C, Calamai M, Nosi D, Ramazzotti M, Giorgetti S, Pavone FS, Bellotti V, Stefani M, Bucciantini M. Molecular insights into cell toxicity of a novel familial amyloidogenic variant of β2-microglobulin. J Cell Mol Med 2016; 20:1443-56. [PMID: 26990223 PMCID: PMC4956941 DOI: 10.1111/jcmm.12833] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Accepted: 02/10/2016] [Indexed: 12/20/2022] Open
Abstract
The first genetic variant of β2‐microglobulin (b2M) associated with a familial form of systemic amyloidosis has been recently described. The mutated protein, carrying a substitution of Asp at position 76 with an Asn (D76N b2M), exhibits a strongly enhanced amyloidogenic tendency to aggregate with respect to the wild‐type protein. In this study, we characterized the D76N b2M aggregation path and performed an unprecedented analysis of the biochemical mechanisms underlying aggregate cytotoxicity. We showed that, contrarily to what expected from other amyloid studies, early aggregates of the mutant are not the most toxic species, despite their higher surface hydrophobicity. By modulating ganglioside GM1 content in cell membrane or synthetic lipid bilayers, we confirmed the pivotal role of this lipid as aggregate recruiter favouring their cytotoxicity. We finally observed that the aggregates bind to the cell membrane inducing an alteration of its elasticity (with possible functional unbalance and cytotoxicity) in GM1‐enriched domains only, thus establishing a link between aggregate‐membrane contact and cell damage.
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Affiliation(s)
- Manuela Leri
- Dipartimento di Scienze Biomediche, Sperimentali e Cliniche 'Mario Serio', Università degli Studi di Firenze, Firenze, Italy
| | - Francesco Bemporad
- Dipartimento di Scienze Biomediche, Sperimentali e Cliniche 'Mario Serio', Università degli Studi di Firenze, Firenze, Italy
| | | | - Claudio Canale
- Dipartimento di Nanofisica, Istituto Italiano di Tecnologia, Genova, Italy
| | - Martino Calamai
- European Laboratory for Non-linear Spectroscopy (LENS), Università degli Studi di Firenze, Sesto Fiorentino, Italy.,National Institute of Optics, Consiglio Nazionale delle Ricerche (CNR), Firenze, Italy
| | - Daniele Nosi
- Dipartimento di Medicina Sperimentale e Clinica, Università degli Studi di Firenze, Firenze, Italy
| | - Matteo Ramazzotti
- Dipartimento di Scienze Biomediche, Sperimentali e Cliniche 'Mario Serio', Università degli Studi di Firenze, Firenze, Italy
| | - Sofia Giorgetti
- Dipartimento di Medicina Molecolare, Istituto di Biochimica, Università degli Studi di Pavia, Pavia, Italy
| | - Francesco S Pavone
- European Laboratory for Non-linear Spectroscopy (LENS), Università degli Studi di Firenze, Sesto Fiorentino, Italy
| | - Vittorio Bellotti
- Dipartimento di Medicina Molecolare, Istituto di Biochimica, Università degli Studi di Pavia, Pavia, Italy.,Wolfson Drug Discovery Unit, Centre for Amyloidosis and Acute Phase Proteins, Division of Medicine, Royal Free Campus University College London, London, UK
| | - Massimo Stefani
- Dipartimento di Scienze Biomediche, Sperimentali e Cliniche 'Mario Serio', Università degli Studi di Firenze, Firenze, Italy.,Centro Interuniversitario per lo Studio delle Malattie Neurodegenerative (CIMN), Firenze, Italy
| | - Monica Bucciantini
- Dipartimento di Scienze Biomediche, Sperimentali e Cliniche 'Mario Serio', Università degli Studi di Firenze, Firenze, Italy.,Centro Interuniversitario per lo Studio delle Malattie Neurodegenerative (CIMN), Firenze, Italy
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102
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Fernández C, Núñez-Ramírez R, Jiménez M, Rivas G, Giraldo R. RepA-WH1, the agent of an amyloid proteinopathy in bacteria, builds oligomeric pores through lipid vesicles. Sci Rep 2016; 6:23144. [PMID: 26984374 PMCID: PMC4794723 DOI: 10.1038/srep23144] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Accepted: 02/29/2016] [Indexed: 12/12/2022] Open
Abstract
RepA-WH1 is a disease-unrelated protein that recapitulates in bacteria key aspects of human amyloid proteinopathies: i) It undergoes ligand-promoted amyloidogenesis in vitro; ii) its aggregates are able to seed/template amyloidosis on soluble protein molecules; iii) its conformation is modulated by Hsp70 chaperones in vivo, generating transmissible amyloid strains; and iv) causes proliferative senescence. Membrane disruption by amyloidogenic oligomers has been found for most proteins causing human neurodegenerative diseases. Here we report that, as for PrP prion and α-synuclein, acidic phospholipids also promote RepA-WH1 amyloidogenesis in vitro. RepA-WH1 molecules bind to liposomes, where the protein assembles oligomeric membrane pores. Fluorescent tracer molecules entrapped in the lumen of the vesicles leak through these pores and RepA-WH1 can then form large aggregates on the surface of the vesicles without inducing their lysis. These findings prove that it is feasible to generate in vitro a synthetic proteinopathy with a minimal set of cytomimetic components and support the view that cell membranes are primary targets in protein amyloidoses.
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Affiliation(s)
- Cristina Fernández
- Department of Cellular and Molecular Biology Centro de Investigaciones Biológicas-CSIC, E28040 Madrid, Spain
| | - Rafael Núñez-Ramírez
- Electron Microscopy Facility, Centro de Investigaciones Biológicas–CSIC, E28040 Madrid, Spain
| | - Mercedes Jiménez
- Department of Cellular and Molecular Biology Centro de Investigaciones Biológicas-CSIC, E28040 Madrid, Spain
| | - Germán Rivas
- Department of Cellular and Molecular Biology Centro de Investigaciones Biológicas-CSIC, E28040 Madrid, Spain
| | - Rafael Giraldo
- Department of Cellular and Molecular Biology Centro de Investigaciones Biológicas-CSIC, E28040 Madrid, Spain
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103
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Li ZL, Ding HM, Ma YQ. Interaction of peptides with cell membranes: insights from molecular modeling. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2016; 28:083001. [PMID: 26828575 DOI: 10.1088/0953-8984/28/8/083001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The investigation of the interaction of peptides with cell membranes is the focus of active research. It can enhance the understanding of basic membrane functions such as membrane transport, fusion, and signaling processes, and it may shed light on potential applications of peptides in biomedicine. In this review, we will present current advances in computational studies on the interaction of different types of peptides with the cell membrane. Depending on the properties of the peptide, membrane, and external environment, the peptide-membrane interaction shows a variety of different forms. Here, on the basis of recent computational progress, we will discuss how different peptides could initiate membrane pores, translocate across the membrane, induce membrane endocytosis, produce membrane curvature, form fibrils on the membrane surface, as well as interact with functional membrane proteins. Finally, we will present a conclusion summarizing recent progress and providing some specific insights into future developments in this field.
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Affiliation(s)
- Zhen-lu Li
- National Laboratory of Solid State Microstructures and Department of Physics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, People's Republic of China
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104
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Nabers A, Ollesch J, Schartner J, Kötting C, Genius J, Haußmann U, Klafki H, Wiltfang J, Gerwert K. An infrared sensor analysing label-free the secondary structure of the Abeta peptide in presence of complex fluids. JOURNAL OF BIOPHOTONICS 2016; 9:224-234. [PMID: 25808829 DOI: 10.1002/jbio.201400145] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Revised: 02/19/2015] [Accepted: 03/01/2015] [Indexed: 06/04/2023]
Abstract
The secondary structure change of the Abeta peptide to beta-sheet was proposed as an early event in Alzheimer's disease. The transition may be used for diagnostics of this disease in an early state. We present an Attenuated Total Reflection (ATR) sensor modified with a specific antibody to extract minute amounts of Abeta peptide out of a complex fluid. Thereby, the Abeta peptide secondary structure was determined in its physiological aqueous environment by FTIR-difference-spectroscopy. The presented results open the door for label-free Alzheimer diagnostics in cerebrospinal fluid or blood. It can be extended to further neurodegenerative diseases. An immunologic ATR-FTIR sensor for Abeta peptide secondary structure analysis in complex fluids is presented.
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Affiliation(s)
- Andreas Nabers
- Protein Research Unit Ruhr within Europe (PURE), Ruhr-University Bochum, Department of Biophysics ND04-596, Universitätsstraße 150, 44780, Bochum, Germany
| | - Julian Ollesch
- Protein Research Unit Ruhr within Europe (PURE), Ruhr-University Bochum, Department of Biophysics ND04-596, Universitätsstraße 150, 44780, Bochum, Germany
| | - Jonas Schartner
- Protein Research Unit Ruhr within Europe (PURE), Ruhr-University Bochum, Department of Biophysics ND04-596, Universitätsstraße 150, 44780, Bochum, Germany
| | - Carsten Kötting
- Protein Research Unit Ruhr within Europe (PURE), Ruhr-University Bochum, Department of Biophysics ND04-596, Universitätsstraße 150, 44780, Bochum, Germany
| | - Just Genius
- Protein Research Unit Ruhr within Europe (PURE), LVR-Hospital Essen, Department of Psychiatry and Psychotherapy, Medical Faculty University of Duisburg-Essen, 45147, Essen, Germany
| | - Ute Haußmann
- Protein Research Unit Ruhr within Europe (PURE), LVR-Hospital Essen, Department of Psychiatry and Psychotherapy, Medical Faculty University of Duisburg-Essen, 45147, Essen, Germany
| | - Hans Klafki
- Protein Research Unit Ruhr within Europe (PURE), LVR-Hospital Essen, Department of Psychiatry and Psychotherapy, Medical Faculty University of Duisburg-Essen, 45147, Essen, Germany
| | - Jens Wiltfang
- Protein Research Unit Ruhr within Europe (PURE), LVR-Hospital Essen, Department of Psychiatry and Psychotherapy, Medical Faculty University of Duisburg-Essen, 45147, Essen, Germany
- University Medical Center, Department of Psychiatry and Psychotherapy, Georg-August-University, 37073, Göttingen, Germany
| | - Klaus Gerwert
- Protein Research Unit Ruhr within Europe (PURE), Ruhr-University Bochum, Department of Biophysics ND04-596, Universitätsstraße 150, 44780, Bochum, Germany.
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105
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Li X, Wan M, Gao L, Fang W. Mechanism of Inhibition of Human Islet Amyloid Polypeptide-Induced Membrane Damage by a Small Organic Fluorogen. Sci Rep 2016; 6:21614. [PMID: 26887358 PMCID: PMC4757883 DOI: 10.1038/srep21614] [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: 06/12/2015] [Accepted: 01/27/2016] [Indexed: 11/09/2022] Open
Abstract
Human islet amyloid polypeptide (hIAPP) is believed to be responsible for the death of insulin-producing β-cells. However, the mechanism of membrane damage at the molecular level has not been fully elucidated. In this article, we employ coarse- grained dissipative particle dynamics simulations to study the interactions between a lipid bilayer membrane composed of 70% zwitterionic lipids and 30% anionic lipids and hIAPPs with α-helical structures. We demonstrated that the key factor controlling pore formation is the combination of peptide charge-induced electroporation and peptide hydrophobicity-induced lipid disordering and membrane thinning. According to these mechanisms, we suggest that a water-miscible tetraphenylethene BSPOTPE is a potent inhibitor to rescue hIAPP-induced cytotoxicity. Our simulations predict that BSPOTPE molecules can bind directly to the helical regions of hIAPP and form oligomers with separated hydrophobic cores and hydrophilic shells. The micelle-like hIAPP-BSPOTPE clusters tend to be retained in the water/membrane interface and aggregate therein rather than penetrate into the membrane. Electrostatic attraction between BSPOTPE and hIAPP also reduces the extent of hIAPP binding to the anionic lipid bilayer. These two modes work together and efficiently prevent membrane poration.
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Affiliation(s)
- Xiaoxu Li
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Mingwei Wan
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Lianghui Gao
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Weihai Fang
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China
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106
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α-Synuclein and huntingtin exon 1 amyloid fibrils bind laterally to the cellular membrane. Sci Rep 2016; 6:19180. [PMID: 26757959 PMCID: PMC4725933 DOI: 10.1038/srep19180] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Accepted: 12/04/2015] [Indexed: 11/08/2022] Open
Abstract
Fibrillar aggregates involved in neurodegenerative diseases have the ability to spread from one cell to another in a prion-like manner. The underlying molecular mechanisms, in particular the binding mode of the fibrils to cell membranes, are poorly understood. In this work we decipher the modality by which aggregates bind to the cellular membrane, one of the obligatory steps of the propagation cycle. By characterizing the binding properties of aggregates made of α-synuclein or huntingtin exon 1 protein displaying similar composition and structure but different lengths to mammalian cells we demonstrate that in both cases aggregates bind laterally to the cellular membrane, with aggregates extremities displaying little or no role in membrane binding. Lateral binding to artificial liposomes was also observed by transmission electron microscopy. In addition we show that although α-synuclein and huntingtin exon 1 fibrils bind both laterally to the cellular membrane, their mechanisms of interaction differ. Our findings have important implications for the development of future therapeutic tools that aim to block protein aggregates propagation in the brain.
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107
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Pithadia A, Brender JR, Fierke CA, Ramamoorthy A. Inhibition of IAPP Aggregation and Toxicity by Natural Products and Derivatives. J Diabetes Res 2016; 2016:2046327. [PMID: 26649317 PMCID: PMC4662995 DOI: 10.1155/2016/2046327] [Citation(s) in RCA: 99] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2015] [Accepted: 04/15/2015] [Indexed: 01/10/2023] Open
Abstract
Fibrillar aggregates of human islet amyloid polypeptide, hIAPP, a pathological feature seen in some diabetes patients, are a likely causative agent for pancreatic beta-cell toxicity, leading to a transition from a state of insulin resistance to type II diabetes through the loss of insulin producing beta-cells by hIAPP induced toxicity. Because of the probable link between hIAPP and the development of type II diabetes, there has been strong interest in developing reagents to study the aggregation of hIAPP and possible therapeutics to block its toxic effects. Natural products are a class of compounds with interesting pharmacological properties against amyloids which have made them interesting targets to study hIAPP. Specifically, the ability of polyphenolic natural products, EGCG, curcumin, and resveratrol, to modulate the aggregation of hIAPP is discussed. Furthermore, we have outlined possible mechanistic discoveries of the interaction of these small molecules with the peptide and how they may mitigate toxicity associated with peptide aggregation. These abundantly found agents have been long used to combat diseases for many years and may serve as useful templates toward developing therapeutics against hIAPP aggregation and toxicity.
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Affiliation(s)
- Amit Pithadia
- Biophysics and Department of Chemistry, University of Michigan, Ann Arbor, MI 48109-1055, USA
| | - Jeffrey R. Brender
- Biophysics and Department of Chemistry, University of Michigan, Ann Arbor, MI 48109-1055, USA
| | - Carol A. Fierke
- Biophysics and Department of Chemistry, University of Michigan, Ann Arbor, MI 48109-1055, USA
| | - Ayyalusamy Ramamoorthy
- Biophysics and Department of Chemistry, University of Michigan, Ann Arbor, MI 48109-1055, USA
- *Ayyalusamy Ramamoorthy:
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108
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Wang C, Cheng F, Xu L, Jia L. HSA targets multiple Aβ42 species and inhibits the seeding-mediated aggregation and cytotoxicity of Aβ42 aggregates. RSC Adv 2016. [DOI: 10.1039/c6ra14590f] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
HSA inhibits Aβ42 fibrillation and cytotoxicity through interfering with different stages of Aβ42 fibrillation and targeting different Aβ42 intermediate aggregates.
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Affiliation(s)
- Conggang Wang
- School of Life Science and Biotechnology
- Dalian University of Technology
- Dalian 116023
- P. R. China
| | - Fang Cheng
- School of Pharmaceutical Science and Technology
- Dalian University of Technology
- Dalian 116023
- P. R. China
| | - Li Xu
- School of Life Science and Biotechnology
- Dalian University of Technology
- Dalian 116023
- P. R. China
| | - Lingyun Jia
- School of Life Science and Biotechnology
- Dalian University of Technology
- Dalian 116023
- P. R. China
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109
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Calabrese AN, Liu Y, Wang T, Musgrave IF, Pukala TL, Tabor RF, Martin LL, Carver JA, Bowie JH. The Amyloid Fibril-Forming Properties of the Amphibian Antimicrobial Peptide Uperin 3.5. Chembiochem 2015; 17:239-46. [PMID: 26676975 DOI: 10.1002/cbic.201500518] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Indexed: 12/13/2022]
Abstract
The amphibian skin is a vast resource for bioactive peptides, which form the basis of the animals' innate immune system. Key components of the secretions of the cutaneous glands are antimicrobial peptides (AMPs), which exert their cytotoxic effects often as a result of membrane disruption. It is becoming increasingly evident that there is a link between the mechanism of action of AMPs and amyloidogenic peptides and proteins. In this work, we demonstrate that the broad-spectrum amphibian AMP uperin 3.5, which has a random-coil structure in solution but adopts an α-helical structure in membrane-like environments, forms amyloid fibrils rapidly in solution at neutral pH. These fibrils are cytotoxic to model neuronal cells in a similar fashion to those formed by the proteins implicated in neurodegenerative diseases. The addition of small quantities of 2,2,2-trifluoroethanol accelerates fibril formation by uperin 3.5, and is correlated with a structural stabilisation induced by this co-solvent. Uperin 3.5 fibril formation and the associated cellular toxicity are inhibited by the polyphenol (-)-epigallocatechin-3-gallate (EGCG). Furthermore, EGCG rapidly dissociates fully formed uperin 3.5 fibrils. Ion mobility-mass spectrometry reveals that uperin 3.5 adopts various oligomeric states in solution. Combined, these observations imply that the mechanism of membrane permeability by uperin 3.5 is related to its fibril-forming properties.
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Affiliation(s)
- Antonio N Calabrese
- School of Physical Sciences or School of Medical Sciences, The University of Adelaide, Adelaide, 5005, South Australia, Australia
| | - Yanqin Liu
- School of Physical Sciences or School of Medical Sciences, The University of Adelaide, Adelaide, 5005, South Australia, Australia.,School of Technology, Hebei Agricultural University, Cangzhou, Hebei, 061100, China
| | - Tianfang Wang
- Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Sippy Downs, 4556, Queensland, Australia
| | - Ian F Musgrave
- School of Physical Sciences or School of Medical Sciences, The University of Adelaide, Adelaide, 5005, South Australia, Australia
| | - Tara L Pukala
- School of Physical Sciences or School of Medical Sciences, The University of Adelaide, Adelaide, 5005, South Australia, Australia
| | - Rico F Tabor
- School of Chemistry, Monash University, Clayton, 3800, Victoria, Australia
| | - Lisandra L Martin
- School of Chemistry, Monash University, Clayton, 3800, Victoria, Australia.
| | - John A Carver
- Research School of Chemistry, The Australian National University, Acton, 2601, Australian Capital Territory, Australia.
| | - John H Bowie
- School of Physical Sciences or School of Medical Sciences, The University of Adelaide, Adelaide, 5005, South Australia, Australia
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110
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Chiang YL, Chang YC, Chiang IC, Mak HM, Hwang IS, Shih YL. Atomic Force Microscopy Characterization of Protein Fibrils Formed by the Amyloidogenic Region of the Bacterial Protein MinE on Mica and a Supported Lipid Bilayer. PLoS One 2015; 10:e0142506. [PMID: 26562523 PMCID: PMC4642933 DOI: 10.1371/journal.pone.0142506] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Accepted: 10/22/2015] [Indexed: 11/18/2022] Open
Abstract
Amyloid fibrils play a crucial role in many human diseases and are found to function in a range of physiological processes from bacteria to human. They have also been gaining importance in nanotechnology applications. Understanding the mechanisms behind amyloid formation can help develop strategies towards the prevention of fibrillation processes or create new technological applications. It is thus essential to observe the structures of amyloids and their self-assembly processes at the nanometer-scale resolution under physiological conditions. In this work, we used highly force-sensitive frequency-modulation atomic force microscopy (FM-AFM) to characterize the fibril structures formed by the N-terminal domain of a bacterial division protein MinE in solution. The approach enables us to investigate the fibril morphology and protofibril organization over time progression and in response to changes in ionic strength, molecular crowding, and upon association with different substrate surfaces. In addition to comparison of the fibril structure and behavior of MinE1-31 under varying conditions, the study also broadens our understanding of the versatile behavior of amyloid-substrate surface interactions.
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Affiliation(s)
- Ya-Ling Chiang
- Institute of Physics, Academia Sinica, Taipei, Taiwan
- Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu, Taiwan
| | - Yuan-Chih Chang
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, Taiwan
| | - I-Chen Chiang
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan
| | - Huey-Ming Mak
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan
| | - Ing-Shouh Hwang
- Institute of Physics, Academia Sinica, Taipei, Taiwan
- Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu, Taiwan
- * E-mail: (ISH), (YLS)
| | - Yu-Ling Shih
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan
- Institute of Biochemical Sciences, National Taiwan University, Taipei, Taiwan
- * E-mail: (ISH), (YLS)
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111
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Newcomb CJ, Sur S, Ortony JH, Lee OS, Matson JB, Boekhoven J, Yu JM, Schatz GC, Stupp SI. Cell death versus cell survival instructed by supramolecular cohesion of nanostructures. Nat Commun 2015; 5:3321. [PMID: 24531236 PMCID: PMC3982852 DOI: 10.1038/ncomms4321] [Citation(s) in RCA: 119] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2013] [Accepted: 01/27/2014] [Indexed: 12/14/2022] Open
Abstract
Many naturally occurring peptides containing cationic and hydrophobic domains have evolved to interact with mammalian cell membranes and have been incorporated into materials for non-viral gene delivery, cancer therapy, or treatment of microbial infections. Their electrostatic attraction to the negatively charged cell surface and hydrophobic interactions with the membrane lipids enable intracellular delivery or cell lysis. While the effects of hydrophobicity and cationic charge of soluble molecules on the cell membrane are well known, the interactions between materials with these molecular features and cells remain poorly understood. Here we report that varying the cohesive forces within nanofibres of supramolecular materials with nearly identical cationic and hydrophobic structure instruct cell death or cell survival. Weak intermolecular bonds promote cell death through disruption of lipid membranes, while materials reinforced by hydrogen bonds support cell viability. These findings provide new strategies to design biomaterials that interact with the cell membrane.
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Affiliation(s)
- Christina J Newcomb
- 1] Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208, USA [2]
| | - Shantanu Sur
- 1] The Institute for BioNanotechnology in Medicine, Northwestern University, Chicago, Illinois 60611, USA [2]
| | - Julia H Ortony
- The Institute for BioNanotechnology in Medicine, Northwestern University, Chicago, Illinois 60611, USA
| | - One-Sun Lee
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, USA
| | - John B Matson
- The Institute for BioNanotechnology in Medicine, Northwestern University, Chicago, Illinois 60611, USA
| | - Job Boekhoven
- The Institute for BioNanotechnology in Medicine, Northwestern University, Chicago, Illinois 60611, USA
| | - Jeong Min Yu
- The Institute for BioNanotechnology in Medicine, Northwestern University, Chicago, Illinois 60611, USA
| | - George C Schatz
- 1] Department of Chemistry, Northwestern University, Evanston, Illinois 60208, USA [2] Department of Chemical and Biological Engineering, Northwestern University, Evanston, Illinois 60208, USA
| | - Samuel I Stupp
- 1] Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208, USA [2] The Institute for BioNanotechnology in Medicine, Northwestern University, Chicago, Illinois 60611, USA [3] Department of Chemistry, Northwestern University, Evanston, Illinois 60208, USA [4] Department of Medicine, Northwestern University, Chicago, Illinois 60611, USA
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112
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Tipping KW, van Oosten-Hawle P, Hewitt EW, Radford SE. Amyloid Fibres: Inert End-Stage Aggregates or Key Players in Disease? Trends Biochem Sci 2015; 40:719-727. [PMID: 26541462 DOI: 10.1016/j.tibs.2015.10.002] [Citation(s) in RCA: 82] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Revised: 09/30/2015] [Accepted: 10/05/2015] [Indexed: 01/08/2023]
Abstract
The formation of amyloid fibres is a hallmark of amyloid disorders. Nevertheless, the lack of correlation between fibre load and disease as observed, for example, in Alzheimer's disease, means that fibres are considered secondary contributors to the onset of cellular dysfunction. Instead, soluble intermediates of amyloid assembly are often described as the agents of toxicity. Here, we discuss recent experimental discoveries which suggest that amyloid fibres should be considered as disease-relevant species that can mediate a range of pathological processes. These include disruption of biological membranes, secondary nucleation, amyloid aggregate transmission, and the disruption of protein homeostasis (proteostasis). Thus, a greater understanding of amyloid fibre biology could enhance prospects of developing therapeutic interventions against this devastating class of protein-misfolding disorders.
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Affiliation(s)
- Kevin W Tipping
- Astbury Centre for Structural Molecular Biology and School of Molecular and Cellular Biology, The University of Leeds, Leeds, LS2 9JT, UK
| | - Patricija van Oosten-Hawle
- Astbury Centre for Structural Molecular Biology and School of Molecular and Cellular Biology, The University of Leeds, Leeds, LS2 9JT, UK
| | - Eric W Hewitt
- Astbury Centre for Structural Molecular Biology and School of Molecular and Cellular Biology, The University of Leeds, Leeds, LS2 9JT, UK
| | - Sheena E Radford
- Astbury Centre for Structural Molecular Biology and School of Molecular and Cellular Biology, The University of Leeds, Leeds, LS2 9JT, UK.
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113
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Zeineddine R, Pundavela JF, Corcoran L, Stewart EM, Do-Ha D, Bax M, Guillemin G, Vine KL, Hatters DM, Ecroyd H, Dobson CM, Turner BJ, Ooi L, Wilson MR, Cashman NR, Yerbury JJ. SOD1 protein aggregates stimulate macropinocytosis in neurons to facilitate their propagation. Mol Neurodegener 2015; 10:57. [PMID: 26520394 PMCID: PMC4628302 DOI: 10.1186/s13024-015-0053-4] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2015] [Accepted: 10/23/2015] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND Amyotrophic Lateral Sclerosis is characterized by a focal onset of symptoms followed by a progressive spread of pathology that has been likened to transmission of infectious prions. Cell-to-cell transmission of SOD1 protein aggregates is dependent on fluid-phase endocytosis pathways, although the precise molecular mechanisms remain to be elucidated. RESULTS We demonstrate in this paper that SOD1 aggregates interact with the cell surface triggering activation of Rac1 and subsequent membrane ruffling permitting aggregate uptake via stimulated macropinocytosis. In addition, other protein aggregates, including those associated with neurodegenerative diseases (TDP-43, Httex146Q, α-synuclein) also trigger membrane ruffling to gain entry into the cell. Aggregates are able to rupture unstructured macropinosomes to enter the cytosol allowing propagation of aggregation to proceed. CONCLUSION Thus, we conclude that in addition to basic proteostasis mechanisms, pathways involved in the activation of macropinocytosis are key determinants in the spread of pathology in these misfolding diseases.
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Affiliation(s)
- Rafaa Zeineddine
- Illawarra Health and Medical Research Institute, Wollongong, Australia, 2522.
- School of Biological Sciences, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, Australia, 2522.
| | - Jay F Pundavela
- Illawarra Health and Medical Research Institute, Wollongong, Australia, 2522.
- School of Biological Sciences, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, Australia, 2522.
| | - Lisa Corcoran
- Illawarra Health and Medical Research Institute, Wollongong, Australia, 2522.
- School of Biological Sciences, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, Australia, 2522.
| | - Elise M Stewart
- Intelligent Polymer Research Institute, University of Wollongong, Wollongong, Australia, 2522.
| | - Dzung Do-Ha
- Illawarra Health and Medical Research Institute, Wollongong, Australia, 2522.
- School of Biological Sciences, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, Australia, 2522.
| | - Monique Bax
- Illawarra Health and Medical Research Institute, Wollongong, Australia, 2522.
- School of Biological Sciences, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, Australia, 2522.
| | - Gilles Guillemin
- Australian School for Advanced Medicine, Macquarie University, Sydney, Australia, 2109.
| | - Kara L Vine
- Illawarra Health and Medical Research Institute, Wollongong, Australia, 2522.
- School of Biological Sciences, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, Australia, 2522.
| | - Danny M Hatters
- Department of Biochemistry and Molecular Biology and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, Australia, 3010.
| | - Heath Ecroyd
- Illawarra Health and Medical Research Institute, Wollongong, Australia, 2522.
- School of Biological Sciences, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, Australia, 2522.
| | | | - Bradley J Turner
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Australia, 3010.
| | - Lezanne Ooi
- Illawarra Health and Medical Research Institute, Wollongong, Australia, 2522.
- School of Biological Sciences, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, Australia, 2522.
| | - Mark R Wilson
- Illawarra Health and Medical Research Institute, Wollongong, Australia, 2522.
- School of Biological Sciences, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, Australia, 2522.
| | - Neil R Cashman
- Department of Medicine (Neurology), University of British Columbia and Vancouver Coastal Health Research Institute, Brain Research Centre, University of British Columbia, Vancouver, Canada, V6T 2B5.
| | - Justin J Yerbury
- Illawarra Health and Medical Research Institute, Wollongong, Australia, 2522.
- School of Biological Sciences, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, Australia, 2522.
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Rembach A, Stingo FC, Peterson C, Vannucci M, Do KA, Wilson WJ, Macaulay SL, Ryan TM, Martins RN, Ames D, Masters CL, Doecke JD. Bayesian graphical network analyses reveal complex biological interactions specific to Alzheimer's disease. J Alzheimers Dis 2015; 44:917-25. [PMID: 25613103 DOI: 10.3233/jad-141497] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
With different approaches to finding prognostic or diagnostic biomarkers for Alzheimer's disease (AD), many studies pursue only brief lists of biomarkers or disease specific pathways, potentially dismissing information from groups of correlated biomarkers. Using a novel Bayesian graphical network method, with data from the Australian Imaging, Biomarkers and Lifestyle (AIBL) study of aging, the aim of this study was to assess the biological connectivity between AD associated blood-based proteins. Briefly, three groups of protein markers (18, 37, and 48 proteins, respectively) were assessed for the posterior probability of biological connection both within and between clinical classifications. Clinical classification was defined in four groups: high performance healthy controls (hpHC), healthy controls (HC), participants with mild cognitive impairment (MCI), and participants with AD. Using the smaller group of proteins, posterior probabilities of network similarity between clinical classifications were very high, indicating no difference in biological connections between groups. Increasing the number of proteins increased the capacity to separate both hpHC and HC apart from the AD group (0 for complete separation, 1 for complete similarity), with posterior probabilities shifting from 0.89 for the 18 protein group, through to 0.54 for the 37 protein group, and finally 0.28 for the 48 protein group. Using this approach, we identified beta-2 microglobulin (β2M) as a potential master regulator of multiple proteins across all classifications, demonstrating that this approach can be used across many data sets to identify novel insights into diseases like AD.
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Affiliation(s)
- Alan Rembach
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, VIC, Australia
| | | | | | | | - Kim-Anh Do
- The MD Anderson Cancer Center, Texas, Houston, USA
| | - William J Wilson
- CSIRO Digital Productivity and Services/Australian e-Health Research Centre, Royal Brisbane and Women's Hospital, Brisbane, QLD, Australia Cooperative Research Centre for Mental Health, Parkville, VIC, Australia
| | - S Lance Macaulay
- Department of Psychiatry, St George's Hospital, University of Melbourne, VIC, Australia
| | - Timothy M Ryan
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, VIC, Australia
| | - Ralph N Martins
- Sir James McCusker Alzheimer's Disease Research Unit, Health Department of WA, Perth, WA, Australia
| | - David Ames
- National Ageing Research Institute, Parkville, VIC, Australia
| | - Colin L Masters
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, VIC, Australia
| | - James D Doecke
- CSIRO Digital Productivity and Services/Australian e-Health Research Centre, Royal Brisbane and Women's Hospital, Brisbane, QLD, Australia Cooperative Research Centre for Mental Health, Parkville, VIC, Australia
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115
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Villar-Piqué A, Lopes da Fonseca T, Outeiro TF. Structure, function and toxicity of alpha-synuclein: the Bermuda triangle in synucleinopathies. J Neurochem 2015; 139 Suppl 1:240-255. [PMID: 26190401 DOI: 10.1111/jnc.13249] [Citation(s) in RCA: 152] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Revised: 06/29/2015] [Accepted: 07/14/2015] [Indexed: 12/11/2022]
Abstract
Parkinson's disease belongs to a group of currently incurable neurodegenerative disorders characterized by the misfolding and accumulation of alpha-synuclein aggregates that are commonly known as synucleinopathies. Clinically, synucleinopathies are heterogeneous, reflecting the somewhat selective neuronal vulnerability characteristic of each disease. The precise molecular underpinnings of synucleinopathies remain unclear, but the process of aggregation of alpha-synuclein appears as a central event. However, there is still no consensus with respect to the toxic forms of alpha-synuclein, hampering our ability to use the protein as a target for therapeutic intervention. To decipher the molecular bases of synucleinopathies, it is essential to understand the complex triangle formed between the structure, function and toxicity of alpha-synuclein. Recently, important steps have been undertaken to elucidate the role of the protein in both physiological and pathological conditions. Here, we provide an overview of recent findings in the field of alpha-synuclein research, and put forward a new perspective over paradigms that persist in the field. Establishing whether alpha-synuclein has a causative role in all synucleinopathies will enable the identification of targets for the development of novel therapeutic strategies for this devastating group of disorders. Alpha-synuclein is the speculated cornerstone of several neurodegenerative disorders known as Synucleinopathies. Nevertheless, the mechanisms underlying the pathogenic effects of this protein remain unknown. Here, we review the recent findings in the three corners of alpha-synuclein biology - structure, function and toxicity - and discuss the enigmatic roads that have accompanied alpha-synuclein from the beginning. This article is part of a special issue on Parkinson disease.
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Affiliation(s)
- Anna Villar-Piqué
- Department of NeuroDegeneration and Restorative Research, Center for Nanoscale Microscopy and Molecular Physiology of the Brain, University Medical Center Göttingen, Göttingen, Germany
| | - Tomás Lopes da Fonseca
- Department of NeuroDegeneration and Restorative Research, Center for Nanoscale Microscopy and Molecular Physiology of the Brain, University Medical Center Göttingen, Göttingen, Germany.,Instituto de Fisiologia, Faculty of Medicine, University of Lisbon, Lisboa, Portugal
| | - Tiago Fleming Outeiro
- Department of NeuroDegeneration and Restorative Research, Center for Nanoscale Microscopy and Molecular Physiology of the Brain, University Medical Center Göttingen, Göttingen, Germany. .,Instituto de Fisiologia, Faculty of Medicine, University of Lisbon, Lisboa, Portugal. .,CEDOC, Faculdade de Ciências Médicas, Universidade Nova de Lisboa, Lisboa, Portugal.
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116
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Plaque-associated lipids in Alzheimer's diseased brain tissue visualized by nonlinear microscopy. Sci Rep 2015; 5:13489. [PMID: 26311128 PMCID: PMC4550829 DOI: 10.1038/srep13489] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Accepted: 07/27/2015] [Indexed: 12/22/2022] Open
Abstract
By simultaneous coherent anti-Stokes Raman scattering (CARS) and 2-photon fluorescence microscopy of Thioflavin-S stained Alzheimer´s diseased human brain tissues, we show evidence of lipid deposits co-localizing with fibrillar β-amyloid (Aβ) plaques. Two lipid morphologies can be observed; lamellar structures and coalescing macro-aggregates of sub-micron sizes to ~25 μm. No significant lipid deposits were observed in non-fibrillar, diffuse plaques identified by Aβ immuno-staining. CARS microscopy of unlabeled samples confirms the lamellar and macro-aggregate lipid morphologies. The composition of the plaques was analyzed by CARS microspectroscopy and Raman microscopy; vibrational signatures of lipids with long acyl chains co-localize with the β-sheet vibrations. The lipid fluidity was evaluated from the CARS spectra, illustrating that the lipid composition/organization varies throughout the plaques. Altogether this indicates close amyloid-lipid interplay in fibrillar Aβ plaques, rendering them more dynamic compositions than previously believed and, hence, potential sources of toxic oligomers.
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117
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Gorbenko G, Trusova V, Girych M, Adachi E, Mizuguchi C, Akaji K, Saito H. FRET evidence for untwisting of amyloid fibrils on the surface of model membranes. SOFT MATTER 2015; 11:6223-6234. [PMID: 26153461 DOI: 10.1039/c5sm00183h] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Apolipoprotein A-I (apoA-I) is an amyloid-forming protein whose amyloidogenic properties are attributed mainly to its N-terminal fragment. Cell membranes are thought to be the primary target for the toxic amyloid aggregates. In the present study Förster resonance energy transfer (FRET) between the membrane fluorescent probe Laurdan as a donor and amyloid-specific dye Thioflavin T (ThT) as an acceptor was employed to explore the interactions of amyloid fibrils from apoA-I variants 1-83/G26R and 1-83/G26R/W@8 with the model membranes composed of phosphatidylcholine and its mixture with cholesterol. The changes in FRET efficiency upon fibril-lipid binding were found to correlate with the extent of protein fibrillization. AFM imaging revealed the presence of two polymorphic states of fibrillar 1-83/G26R/W@8 with the helical and twisted ribbon morphologies. The simulation-based analysis of the experimental FRET profiles provided the arguments in favor of untwisting of fibrillar assemblies upon their interaction with the model membranes. Evidence for the face-on orientation and superficial bilayer location of the membrane-bound fragments of 1-83/G26R/W@8 fibrils was obtained.
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Affiliation(s)
- Galyna Gorbenko
- Department of Nuclear and Medical Physics, V.N. Karazin Kharkiv National University, 4 Svobody Sq., Kharkov, 61022, Ukraine.
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118
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Shaham-Niv S, Adler-Abramovich L, Schnaider L, Gazit E. Extension of the generic amyloid hypothesis to nonproteinaceous metabolite assemblies. SCIENCE ADVANCES 2015; 1:e1500137. [PMID: 26601224 PMCID: PMC4643800 DOI: 10.1126/sciadv.1500137] [Citation(s) in RCA: 108] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Accepted: 06/25/2015] [Indexed: 05/26/2023]
Abstract
The accumulation of amyloid fibrils is the hallmark of several major human diseases. Although the formation of these supramolecular entities has previously been associated with proteins and peptides, it was later demonstrated that even phenylalanine, a single amino acid, can form fibrils that have amyloid-like biophysical, biochemical, and cytotoxic properties. Moreover, the generation of antibodies against these assemblies in phenylketonuria patients and the correlating mice model suggested a pathological role for the assemblies. We determine that several other metabolites that accumulate in metabolic disorders form ordered amyloid-like ultrastructures, which induce apoptotic cell death, as observed for amyloid structures. The formation of amyloid-like assemblies by metabolites implies a general phenomenon of amyloid formation, not limited to proteins and peptides, and offers a new paradigm for metabolic diseases.
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Affiliation(s)
- Shira Shaham-Niv
- Department of Molecular Microbiology and Biotechnology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
| | - Lihi Adler-Abramovich
- Department of Molecular Microbiology and Biotechnology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
- Department of Oral Biology, The Goldschleger School of Dental Medicine, Tel Aviv Univeristy, Tel Aviv 69978, Israel
| | - Lee Schnaider
- Department of Molecular Microbiology and Biotechnology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
| | - Ehud Gazit
- Department of Molecular Microbiology and Biotechnology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
- Department of Materials Science and Engineering, Iby and Aladar Fleischman Faculty of Engineering, Tel Aviv University, Tel Aviv 69978, Israel
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119
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The route to protein aggregate superstructures: Particulates and amyloid-like spherulites. FEBS Lett 2015; 589:2448-63. [DOI: 10.1016/j.febslet.2015.07.006] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Revised: 07/02/2015] [Accepted: 07/06/2015] [Indexed: 12/15/2022]
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120
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Smith RAS, Nabok A, Blakeman BJF, Xue WF, Abell B, Smith DP. Analysis of Toxic Amyloid Fibril Interactions at Natively Derived Membranes by Ellipsometry. PLoS One 2015; 10:e0132309. [PMID: 26172440 PMCID: PMC4501548 DOI: 10.1371/journal.pone.0132309] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Accepted: 06/11/2015] [Indexed: 12/26/2022] Open
Abstract
There is an ongoing debate regarding the culprits of cytotoxicity associated with amyloid disorders. Although small pre-fibrillar amyloid oligomers have been implicated as the primary toxic species, the fibrillar amyloid material itself can also induce cytotoxicity. To investigate membrane disruption and cytotoxic effects associated with intact and fragmented fibrils, the novel in situ spectroscopic technique of Total Internal Reflection Ellipsometry (TIRE) was used. Fibril lipid interactions were monitored using natively derived whole cell membranes as a model of the in vivo environment. We show that fragmented fibrils have an increased ability to disrupt these natively derived membranes by causing a loss of material from the deposited surface when compared with unfragmented fibrils. This effect was corroborated by observations of membrane disruption in live cells, and by dye release assay using synthetic liposomes. Through these studies we demonstrate the use of TIRE for the analysis of protein-lipid interactions on natively derived lipid surfaces, and provide an explanation on how amyloid fibrils can cause a toxic gain of function, while entangled amyloid plaques exert minimal biological activity.
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Affiliation(s)
- Rachel A. S. Smith
- Biomedical Research Centre, Sheffield Hallam University, Sheffield, United Kingdom
| | - Aleksey Nabok
- Materials and Engineering Research Institute, Sheffield Hallam University, Sheffield, United Kingdom
| | - Ben J. F. Blakeman
- School of Biosciences, University of Kent, Canterbury, Kent, United Kingdom
| | - Wei-Feng Xue
- School of Biosciences, University of Kent, Canterbury, Kent, United Kingdom
| | - Benjamin Abell
- Biomedical Research Centre, Sheffield Hallam University, Sheffield, United Kingdom
| | - David P. Smith
- Biomedical Research Centre, Sheffield Hallam University, Sheffield, United Kingdom
- * E-mail:
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121
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Reynolds NP, Charnley M, Bongiovanni MN, Hartley PG, Gras SL. Biomimetic Topography and Chemistry Control Cell Attachment to Amyloid Fibrils. Biomacromolecules 2015; 16:1556-65. [DOI: 10.1021/acs.biomac.5b00114] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- Nicholas P. Reynolds
- Manufacturing
Flagship, CSIRO, Bayview Avenue, Clayton, Victoria 3169, Australia
| | | | - Marie N. Bongiovanni
- Department
of Chemistry, University of Cambridge, Cambridge CB2 1EW, United Kingdom
| | - Patrick G. Hartley
- Energy
Flagship, CSIRO, Private Bag 10, Bayview Avenue, Clayton, Victoria 3169, Australia
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122
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pH-induced molecular shedding drives the formation of amyloid fibril-derived oligomers. Proc Natl Acad Sci U S A 2015; 112:5691-6. [PMID: 25902516 DOI: 10.1073/pnas.1423174112] [Citation(s) in RCA: 91] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Amyloid disorders cause debilitating illnesses through the formation of toxic protein aggregates. The mechanisms of amyloid toxicity and the nature of species responsible for mediating cellular dysfunction remain unclear. Here, using β2-microglobulin (β2m) as a model system, we show that the disruption of membranes by amyloid fibrils is caused by the molecular shedding of membrane-active oligomers in a process that is dependent on pH. Using thioflavin T (ThT) fluorescence, NMR, EM and fluorescence correlation spectroscopy (FCS), we show that fibril disassembly at pH 6.4 results in the formation of nonnative spherical oligomers that disrupt synthetic membranes. By contrast, fibril dissociation at pH 7.4 results in the formation of nontoxic, native monomers. Chemical cross-linking or interaction with hsp70 increases the kinetic stability of fibrils and decreases their capacity to cause membrane disruption and cellular dysfunction. The results demonstrate how pH can modulate the deleterious effects of preformed amyloid aggregates and suggest why endocytic trafficking through acidic compartments may be a key factor in amyloid disease.
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123
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Nanomechanics and intermolecular forces of amyloid revealed by four-dimensional electron microscopy. Proc Natl Acad Sci U S A 2015; 112:3380-5. [PMID: 25733888 DOI: 10.1073/pnas.1502214112] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The amyloid state of polypeptides is a stable, highly organized structural form consisting of laterally associated β-sheet protofilaments that may be adopted as an alternative to the functional, native state. Identifying the balance of forces stabilizing amyloid is fundamental to understanding the wide accessibility of this state to peptides and proteins with unrelated primary sequences, various chain lengths, and widely differing native structures. Here, we use four-dimensional electron microscopy to demonstrate that the forces acting to stabilize amyloid at the atomic level are highly anisotropic, that an optimized interbackbone hydrogen-bonding network within β-sheets confers 20 times more rigidity on the structure than sequence-specific sidechain interactions between sheets, and that electrostatic attraction of protofilaments is only slightly stronger than these weak amphiphilic interactions. The potential biological relevance of the deposition of such a highly anisotropic biomaterial in vivo is discussed.
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124
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Cu2+ accentuates distinct misfolding of Aβ(1–40) and Aβ(1–42) peptides, and potentiates membrane disruption. Biochem J 2015; 466:233-42. [DOI: 10.1042/bj20141168] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Cu2+ homoeostasis has been linked to Alzheimer's disease. We demonstrate that Cu2+ causes oligomer and protofibril formation for Aβ(1–42) only, and promotes membrane disruption. Differences in synaptic toxicity of Aβ(1–42) and Aβ(1–40) may be enhanced by the presence of Cu2+.
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125
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Andreasen M, Lorenzen N, Otzen D. Interactions between misfolded protein oligomers and membranes: A central topic in neurodegenerative diseases? BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2015; 1848:1897-907. [PMID: 25666871 DOI: 10.1016/j.bbamem.2015.01.018] [Citation(s) in RCA: 83] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Revised: 01/26/2015] [Accepted: 01/29/2015] [Indexed: 11/19/2022]
Abstract
The deposition of amyloid material has been associated with many different diseases. Although these diseases are very diverse the amyloid material share many common features such as cross-β-sheet structure of the backbone of the proteins deposited. Another common feature of the aggregation process for a wide variety of proteins is the presence of prefibrillar oligomers. These oligomers are linked to the cytotoxicity occurring during the aggregation of proteins. These prefibrillar oligomers interact extensively with lipid membranes and in some cases leads to destabilization of lipid membranes. This interaction is however highly dependent on the nature of both the oligomer and the lipids. Anionic lipids are often required for interaction with the lipid membrane while increased exposure of hydrophobic patches from highly dynamic protein oligomers are structural determinants of cytotoxicity of the oligomers. To explore the oligomer lipid interaction in detail the interaction between oligomers of α-synuclein and the 4th fasciclin-1 domain of TGFBIp with lipid membranes will be examined here. For both proteins the dynamic species are the ones causing membrane destabilization and the membrane interaction is primarily seen when the lipid membranes contain anionic lipids. Hence the dynamic nature of oligomers with exposed hydrophobic patches alongside the presence of anionic lipids could be essential for the cytotoxicity observed for prefibrillar oligomers in general. This article is part of a Special Issue entitled: Lipid-protein interactions.
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Affiliation(s)
- Maria Andreasen
- Department of Chemistry, Cambridge University, Lensfield Road, Cambridge CB2 1EW, UK; Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Gustav Wieds Vej 14, DK 8000 Aarhus C, Denmark
| | - Nikolai Lorenzen
- Department of Protein Biophysics and Formulation, Biopharmaceuticals Research Unit, Novo Nordisk A/S, 2760 Måløv, Denmark
| | - Daniel Otzen
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Gustav Wieds Vej 14, DK 8000 Aarhus C, Denmark.
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126
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Chaudhary H, Stefanovic AND, Subramaniam V, Claessens MMAE. Membrane interactions and fibrillization of α-synuclein play an essential role in membrane disruption. FEBS Lett 2015; 588:4457-63. [PMID: 25448986 DOI: 10.1016/j.febslet.2014.10.016] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2014] [Revised: 10/13/2014] [Accepted: 10/15/2014] [Indexed: 12/22/2022]
Abstract
We studied α-synuclein (αS) aggregation in giant vesicles, and observed dramatic membrane disintegration, as well as lipid incorporation into micrometer-sized suprafibrillar aggregates. In the presence of dye-filled vesicles, dye leakage and fibrillization happen concurrently. However, growing fibrils do not impair the integrity of phospholipid vesicles that have a low affinity for αS. Seeding αS aggregation accelerates dye leakage, indicating that oligomeric species are not required to explain the observed effect. The evolving picture suggests that fibrils that appear in solution bind membranes and recruit membrane-bound monomers, resulting in lipid extraction, membrane destabilization and the formation of lipid-containing suprafibrillar aggregates.
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Affiliation(s)
- Himanshu Chaudhary
- Nanobiophysics Group, MESA+ Institute for Nanotechnology, Department of Science and Technology, University Twente, 7500 AE Enschede, The Netherlands
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127
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Membrane Effects of N-Terminal Fragment of Apolipoprotein A-I: A Fluorescent Probe Study. J Fluoresc 2015; 25:253-61. [DOI: 10.1007/s10895-015-1501-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2014] [Accepted: 01/02/2015] [Indexed: 10/24/2022]
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128
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Interactions of Lipid Membranes with Fibrillar Protein Aggregates. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2015; 855:135-55. [PMID: 26149929 DOI: 10.1007/978-3-319-17344-3_6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Amyloid fibrils are an intriguing class of protein aggregates with distinct physicochemical, structural and morphological properties. They display peculiar membrane-binding behavior, thus adding complexity to the problem of protein-lipid interactions. The consensus that emerged during the past decade is that amyloid cytotoxicity arises from a continuum of cross-β-sheet assemblies including mature fibrils. Based on literature survey and our own data, in this chapter we address several aspects of fibril-lipid interactions, including (i) the effects of amyloid assemblies on molecular organization of lipid bilayer; (ii) competition between fibrillar and monomeric membrane-associating proteins for binding to the lipid surface; and (iii) the effects of lipids on the structural morphology of fibrillar aggregates. To illustrate some of the processes occurring in fibril-lipid systems, we present and analyze fluorescence data reporting on lipid bilayer interactions with fibrillar lysozyme and with the N-terminal 83-residue fragment of amyloidogenic mutant apolipoprotein A-I, 1-83/G26R/W@8. The results help understand possible mechanisms of interaction and mutual remodeling of amyloid fibers and lipid membranes, which may contribute to amyloid cytotoxicity.
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129
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Jakhria T, Hellewell AL, Porter MY, Jackson MP, Tipping KW, Xue WF, Radford SE, Hewitt EW. β2-microglobulin amyloid fibrils are nanoparticles that disrupt lysosomal membrane protein trafficking and inhibit protein degradation by lysosomes. J Biol Chem 2014; 289:35781-94. [PMID: 25378395 PMCID: PMC4276847 DOI: 10.1074/jbc.m114.586222] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Fragmentation of amyloid fibrils produces fibrils that are reduced in length but have an otherwise unchanged molecular architecture. The resultant nanoscale fibril particles inhibit the cellular reduction of the tetrazolium dye 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), a substrate commonly used to measure cell viability, to a greater extent than unfragmented fibrils. Here we show that the internalization of β2-microglobulin (β2m) amyloid fibrils is dependent on fibril length, with fragmented fibrils being more efficiently internalized by cells. Correspondingly, inhibiting the internalization of fragmented β2m fibrils rescued cellular MTT reduction. Incubation of cells with fragmented β2m fibrils did not, however, cause cell death. Instead, fragmented β2m fibrils accumulate in lysosomes, alter the trafficking of lysosomal membrane proteins, and inhibit the degradation of a model protein substrate by lysosomes. These findings suggest that nanoscale fibrils formed early during amyloid assembly reactions or by the fragmentation of longer fibrils could play a role in amyloid disease by disrupting protein degradation by lysosomes and trafficking in the endolysosomal pathway.
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Affiliation(s)
- Toral Jakhria
- From the School of Molecular and Cellular Biology and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Andrew L Hellewell
- From the School of Molecular and Cellular Biology and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Morwenna Y Porter
- From the School of Molecular and Cellular Biology and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Matthew P Jackson
- From the School of Molecular and Cellular Biology and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Kevin W Tipping
- From the School of Molecular and Cellular Biology and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Wei-Feng Xue
- From the School of Molecular and Cellular Biology and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Sheena E Radford
- From the School of Molecular and Cellular Biology and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Eric W Hewitt
- From the School of Molecular and Cellular Biology and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom
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130
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Jordens S, Riley EE, Usov I, Isa L, Olmsted PD, Mezzenga R. Adsorption at liquid interfaces induces amyloid fibril bending and ring formation. ACS NANO 2014; 8:11071-9. [PMID: 25338060 DOI: 10.1021/nn504249x] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Protein fibril accumulation at interfaces is an important step in many physiological processes and neurodegenerative diseases as well as in designing materials. Here we show, using β-lactoglobulin fibrils as a model, that semiflexible fibrils exposed to a surface do not possess the Gaussian distribution of curvatures characteristic for wormlike chains, but instead exhibit a spontaneous curvature, which can even lead to ring-like conformations. The long-lived presence of such rings is confirmed by atomic force microscopy, cryogenic scanning electron microscopy, and passive probe particle tracking at air- and oil-water interfaces. We reason that this spontaneous curvature is governed by structural characteristics on the molecular level and is to be expected when a chiral and polar fibril is placed in an inhomogeneous environment such as an interface. By testing β-lactoglobulin fibrils with varying average thicknesses, we conclude that fibril thickness plays a determining role in the propensity to form rings.
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Affiliation(s)
- Sophia Jordens
- Department of Health Sciences & Technology, Laboratory of Food & Soft Materials, ETH Zurich , 8092 Zurich, Switzerland
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131
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Jang H, Arce FT, Ramachandran S, Kagan BL, Lal R, Nussinov R. Disordered amyloidogenic peptides may insert into the membrane and assemble into common cyclic structural motifs. Chem Soc Rev 2014; 43:6750-64. [PMID: 24566672 PMCID: PMC4143503 DOI: 10.1039/c3cs60459d] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Aggregation of disordered amyloidogenic peptides into oligomers is the causative agent of amyloid-related diseases. In solution, disordered protein states are characterized by heterogeneous ensembles. Among these, β-rich conformers self-assemble via a conformational selection mechanism to form energetically-favored cross-β structures, regardless of their precise sequences. These disordered peptides can also penetrate the membrane, and electrophysiological data indicate that they form ion-conducting channels. Based on these and additional data, including imaging and molecular dynamics simulations of a range of amyloid peptides, Alzheimer's amyloid-β (Aβ) peptide, its disease-related variants with point mutations and N-terminal truncated species, other amyloidogenic peptides, as well as a cytolytic peptide and a synthetic gel-forming peptide, we suggest that disordered amyloidogenic peptides can also present a common motif in the membrane. The motif consists of curved, moon-like β-rich oligomers associated into annular organizations. The motif is favored in the lipid bilayer since it permits hydrophobic side chains to face and interact with the membrane and the charged/polar residues to face the solvated channel pores. Such channels are toxic since their pores allow uncontrolled leakage of ions into/out of the cell, destabilizing cellular ionic homeostasis. Here we detail Aβ, whose aggregation is associated with Alzheimer's disease (AD) and for which there are the most abundant data. AD is a protein misfolding disease characterized by a build-up of Aβ peptide as senile plaques, neurodegeneration, and memory loss. Excessively produced Aβ peptides may directly induce cellular toxicity, even without the involvement of membrane receptors through Aβ peptide-plasma membrane interactions.
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Affiliation(s)
- Hyunbum Jang
- Cancer and Inflammation Program, National Cancer Institute at Frederick, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, Maryland 21702, U.S.A
| | - Fernando Teran Arce
- Departments of Bioengineering and of Mechanical and Aerospace Engineering, and Materials Science Program, University of California, San Diego, La Jolla, California 92093, U.S.A
| | - Srinivasan Ramachandran
- Departments of Bioengineering and of Mechanical and Aerospace Engineering, and Materials Science Program, University of California, San Diego, La Jolla, California 92093, U.S.A
| | - Bruce L. Kagan
- Department of Psychiatry, David Geffen School of Medicine, Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, California 90024, U.S.A
| | - Ratnesh Lal
- Departments of Bioengineering and of Mechanical and Aerospace Engineering, and Materials Science Program, University of California, San Diego, La Jolla, California 92093, U.S.A
| | - Ruth Nussinov
- Cancer and Inflammation Program, National Cancer Institute at Frederick, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, Maryland 21702, U.S.A
- Department of Human Molecular Genetics and Biochemistry, Sackler School of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
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132
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van Maarschalkerweerd A, Vetri V, Langkilde AE, Foderà V, Vestergaard B. Protein/lipid coaggregates are formed during α-synuclein-induced disruption of lipid bilayers. Biomacromolecules 2014; 15:3643-54. [PMID: 25210839 DOI: 10.1021/bm500937p] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Amyloid formation is associated with neurodegenerative diseases such as Parkinson's disease (PD). Significant α-synuclein (αSN) deposition in lipid-rich Lewy bodies is a hallmark of PD. Nonetheless, an unraveling of the connection between neurodegeneration and amyloid fibrils, including the molecular mechanisms behind potential amyloid-mediated toxic effects, is still missing. Interaction between amyloid aggregates and the lipid cell membrane is expected to play a key role in the disease progress. Here, we present experimental data based on hybrid analysis of two-photon-microscopy, solution small-angle X-ray scattering and circular dichroism data. Data show in real time changes in liposome morphology and stability upon protein addition and reveal that membrane disruption mediated by amyloidogenic αSN is associated with dehydration of anionic lipid membranes and stimulation of protein secondary structure. As a result of membrane fragmentation, soluble αSN:-lipid coaggregates are formed, hence, suggesting a novel molecular mechanism behind PD amyloid cytotoxicity.
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Affiliation(s)
- Andreas van Maarschalkerweerd
- Department of Drug Design and Pharmacology, University of Copenhagen , Universitetsparken 2, 2100 Copenhagen, Denmark
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133
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Xue WF, Radford SE. An imaging and systems modeling approach to fibril breakage enables prediction of amyloid behavior. Biophys J 2014; 105:2811-9. [PMID: 24359753 DOI: 10.1016/j.bpj.2013.10.034] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2013] [Revised: 10/16/2013] [Accepted: 10/29/2013] [Indexed: 12/01/2022] Open
Abstract
Delineating the nanoscale properties and the dynamic assembly and disassembly behaviors of amyloid fibrils is key for technological applications that use the material properties of amyloid fibrils, as well as for developing treatments of amyloid-associated disease. However, quantitative mechanistic understanding of the complex processes involving these heterogeneous supramolecular systems presents challenges that have yet to be resolved. Here, we develop an approach that is capable of resolving the time dependence of fibril particle concentration, length distribution, and length and position dependence of fibril fragmentation rates using a generic mathematical framework combined with experimental data derived from atomic force microscopy analysis of fibril length distributions. By application to amyloid assembly of β2-microglobulin in vitro under constant mechanical stirring, we present a full description of the fibril fragmentation and growth behavior, and demonstrate the predictive power of the approach in terms of the samples' fibril dimensions, fibril load, and their efficiency to seed the growth of new amyloid fibrils. The approach developed offers opportunities to determine, quantify, and predict the course and the consequences of amyloid assembly.
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Affiliation(s)
- Wei-Feng Xue
- School of Biosciences, University of Kent, Canterbury, United Kingdom; Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom.
| | - Sheena E Radford
- Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom
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134
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Goodchild SC, Sheynis T, Thompson R, Tipping KW, Xue WF, Ranson NA, Beales PA, Hewitt EW, Radford SE. β2-Microglobulin amyloid fibril-induced membrane disruption is enhanced by endosomal lipids and acidic pH. PLoS One 2014; 9:e104492. [PMID: 25100247 PMCID: PMC4123989 DOI: 10.1371/journal.pone.0104492] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2014] [Accepted: 07/11/2014] [Indexed: 12/28/2022] Open
Abstract
Although the molecular mechanisms underlying the pathology of amyloidoses are not well understood, the interaction between amyloid proteins and cell membranes is thought to play a role in several amyloid diseases. Amyloid fibrils of β2-microglobulin (β2m), associated with dialysis-related amyloidosis (DRA), have been shown to cause disruption of anionic lipid bilayers in vitro. However, the effect of lipid composition and the chemical environment in which β2m-lipid interactions occur have not been investigated previously. Here we examine membrane damage resulting from the interaction of β2m monomers and fibrils with lipid bilayers. Using dye release, tryptophan fluorescence quenching and fluorescence confocal microscopy assays we investigate the effect of anionic lipid composition and pH on the susceptibility of liposomes to fibril-induced membrane damage. We show that β2m fibril-induced membrane disruption is modulated by anionic lipid composition and is enhanced by acidic pH. Most strikingly, the greatest degree of membrane disruption is observed for liposomes containing bis(monoacylglycero)phosphate (BMP) at acidic pH, conditions likely to reflect those encountered in the endocytic pathway. The results suggest that the interaction between β2m fibrils and membranes of endosomal origin may play a role in the molecular mechanism of β2m amyloid-associated osteoarticular tissue destruction in DRA.
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Affiliation(s)
- Sophia C. Goodchild
- Astbury Centre for Structural Molecular Biology and School of Molecular and Cellular Biology, University of Leeds, Leeds, United Kingdom
| | - Tania Sheynis
- Astbury Centre for Structural Molecular Biology and School of Molecular and Cellular Biology, University of Leeds, Leeds, United Kingdom
| | - Rebecca Thompson
- Astbury Centre for Structural Molecular Biology and School of Molecular and Cellular Biology, University of Leeds, Leeds, United Kingdom
| | - Kevin W. Tipping
- Astbury Centre for Structural Molecular Biology and School of Molecular and Cellular Biology, University of Leeds, Leeds, United Kingdom
| | - Wei-Feng Xue
- Astbury Centre for Structural Molecular Biology and School of Molecular and Cellular Biology, University of Leeds, Leeds, United Kingdom
| | - Neil A. Ranson
- Astbury Centre for Structural Molecular Biology and School of Molecular and Cellular Biology, University of Leeds, Leeds, United Kingdom
| | - Paul A. Beales
- Astbury Centre for Structural Molecular Biology and School of Chemistry, University of Leeds, Leeds, United Kingdom
| | - Eric W. Hewitt
- Astbury Centre for Structural Molecular Biology and School of Molecular and Cellular Biology, University of Leeds, Leeds, United Kingdom
| | - Sheena E. Radford
- Astbury Centre for Structural Molecular Biology and School of Molecular and Cellular Biology, University of Leeds, Leeds, United Kingdom
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135
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Cho MH, Cho K, Kang HJ, Jeon EY, Kim HS, Kwon HJ, Kim HM, Kim DH, Yoon SY. Autophagy in microglia degrades extracellular β-amyloid fibrils and regulates the NLRP3 inflammasome. Autophagy 2014; 10:1761-75. [PMID: 25126727 DOI: 10.4161/auto.29647] [Citation(s) in RCA: 291] [Impact Index Per Article: 29.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Accumulation of β-amyloid (Aβ) and resultant inflammation are critical pathological features of Alzheimer disease (AD). Microglia, a primary immune cell in brain, ingests and degrades extracellular Aβ fibrils via the lysosomal system. Autophagy is a catabolic process that degrades native cellular components, however, the role of autophagy in Aβ degradation by microglia and its effects on AD are unknown. Here we demonstrate a novel role for autophagy in the clearance of extracellular Aβ fibrils by microglia and in the regulation of the Aβ-induced NLRP3 (NLR family, pyrin domain containing 3) inflammasome using microglia specific atg7 knockout mice and cell cultures. We found in microglial cultures that Aβ interacts with MAP1LC3B-II via OPTN/optineurin and is degraded by an autophagic process mediated by the PRKAA1 pathway. We anticipate that enhancing microglial autophagy may be a promising new therapeutic strategy for AD.
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Affiliation(s)
- Mi-Hyang Cho
- Alzheimer Disease Experts Lab (ADEL); Asan Institute of Life Sciences; Asan Medical Center; University of Ulsan College of Medicine; Seoul, Korea; Department of Anatomy and Cell Biology; University of Ulsan College of Medicine; Seoul, Korea; Bio-Medical Institute of Technology (BMIT); University of Ulsan College of Medicine; Seoul, Korea; Cell Dysfunction Research Center (CDRC); University of Ulsan College of Medicine; Seoul, Korea
| | - Kwangmin Cho
- Alzheimer Disease Experts Lab (ADEL); Asan Institute of Life Sciences; Asan Medical Center; University of Ulsan College of Medicine; Seoul, Korea; Department of Anatomy and Cell Biology; University of Ulsan College of Medicine; Seoul, Korea; Bio-Medical Institute of Technology (BMIT); University of Ulsan College of Medicine; Seoul, Korea; Cell Dysfunction Research Center (CDRC); University of Ulsan College of Medicine; Seoul, Korea
| | - Hoe-Jin Kang
- Alzheimer Disease Experts Lab (ADEL); Asan Institute of Life Sciences; Asan Medical Center; University of Ulsan College of Medicine; Seoul, Korea; Department of Anatomy and Cell Biology; University of Ulsan College of Medicine; Seoul, Korea; Bio-Medical Institute of Technology (BMIT); University of Ulsan College of Medicine; Seoul, Korea; Cell Dysfunction Research Center (CDRC); University of Ulsan College of Medicine; Seoul, Korea
| | - Eun-Young Jeon
- Alzheimer Disease Experts Lab (ADEL); Asan Institute of Life Sciences; Asan Medical Center; University of Ulsan College of Medicine; Seoul, Korea; Department of Anatomy and Cell Biology; University of Ulsan College of Medicine; Seoul, Korea; Bio-Medical Institute of Technology (BMIT); University of Ulsan College of Medicine; Seoul, Korea; Cell Dysfunction Research Center (CDRC); University of Ulsan College of Medicine; Seoul, Korea
| | - Hun-Sik Kim
- Bio-Medical Institute of Technology (BMIT); University of Ulsan College of Medicine; Seoul, Korea; Cell Dysfunction Research Center (CDRC); University of Ulsan College of Medicine; Seoul, Korea; Department of Medicine; Graduate School; University of Ulsan College of Medicine; Seoul, Korea
| | - Hyung-Joon Kwon
- Bio-Medical Institute of Technology (BMIT); University of Ulsan College of Medicine; Seoul, Korea; Department of Medicine; Graduate School; University of Ulsan College of Medicine; Seoul, Korea
| | - Hong-Mi Kim
- Bio-Medical Institute of Technology (BMIT); University of Ulsan College of Medicine; Seoul, Korea; Department of Medicine; Graduate School; University of Ulsan College of Medicine; Seoul, Korea
| | - Dong-Hou Kim
- Alzheimer Disease Experts Lab (ADEL); Asan Institute of Life Sciences; Asan Medical Center; University of Ulsan College of Medicine; Seoul, Korea; Department of Anatomy and Cell Biology; University of Ulsan College of Medicine; Seoul, Korea; Bio-Medical Institute of Technology (BMIT); University of Ulsan College of Medicine; Seoul, Korea; Cell Dysfunction Research Center (CDRC); University of Ulsan College of Medicine; Seoul, Korea
| | - Seung-Yong Yoon
- Alzheimer Disease Experts Lab (ADEL); Asan Institute of Life Sciences; Asan Medical Center; University of Ulsan College of Medicine; Seoul, Korea; Department of Anatomy and Cell Biology; University of Ulsan College of Medicine; Seoul, Korea; Bio-Medical Institute of Technology (BMIT); University of Ulsan College of Medicine; Seoul, Korea; Cell Dysfunction Research Center (CDRC); University of Ulsan College of Medicine; Seoul, Korea
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136
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Morriss-Andrews A, Brown FLH, Shea JE. A coarse-grained model for peptide aggregation on a membrane surface. J Phys Chem B 2014; 118:8420-32. [PMID: 24791936 DOI: 10.1021/jp502871m] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The aggregation of peptides on a lipid bilayer is studied using coarse-grained molecular dynamics in implicit solvent. Peptides bind to and self-assemble on the membrane surface into β-rich fibrillar aggregates, even under conditions where only disordered oligomers form in bulk solution. Relative to a solid surface, the membrane surface facilitates peptide mobility and a more complex network of morphology transitions as aggregation proceeds. Additionally, final aggregate structures realized on the membrane surface are distinct from those observed on a comparable solid surface. The aggregated fibrils alter the local structure and material properties of the lipid bilayer in their immediate vicinity but have only a modest effect on the overall bending rigidity of the bilayer.
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Affiliation(s)
- Alex Morriss-Andrews
- Department of Physics, University of California Santa Barbara , Santa Barbara, California 93106, United States
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137
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Marshall KE, Marchante R, Xue WF, Serpell LC. The relationship between amyloid structure and cytotoxicity. Prion 2014; 8:28860. [PMID: 24819071 PMCID: PMC4189889 DOI: 10.4161/pri.28860] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Self-assembly of proteins and peptides into amyloid structures has been the subject of intense and focused research due to their association with neurodegenerative, age-related human diseases and transmissible prion diseases in humans and mammals. Of the disease associated amyloid assemblies, a diverse array of species, ranging from small oligomeric assembly intermediates to fibrillar structures, have been shown to have toxic potential. Equally, a range of species formed by the same disease associated amyloid sequences have been found to be relatively benign under comparable monomer equivalent concentrations and conditions. In recent years, an increasing number of functional amyloid systems have also been found. These developments show that not all amyloid structures are generically toxic to cells. Given these observations, it is important to understand why amyloid structures may encode such varied toxic potential despite sharing a common core molecular architecture. Here, we discuss possible links between different aspects of amyloidogenic structures and assembly mechanisms with their varied functional effects. We propose testable hypotheses for the relationship between amyloid structure and its toxic potential in the context of recent reports on amyloid sequence, structure, and toxicity relationships.
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Affiliation(s)
- Karen E Marshall
- School of Life Sciences; University of Sussex; Falmer, East Sussex UK; School of Biological Sciences; University of Kent; Canterbury, Kent UK
| | - Ricardo Marchante
- School of Life Sciences; University of Sussex; Falmer, East Sussex UK; School of Biological Sciences; University of Kent; Canterbury, Kent UK
| | - Wei-Feng Xue
- School of Life Sciences; University of Sussex; Falmer, East Sussex UK; School of Biological Sciences; University of Kent; Canterbury, Kent UK
| | - Louise C Serpell
- School of Life Sciences; University of Sussex; Falmer, East Sussex UK; School of Biological Sciences; University of Kent; Canterbury, Kent UK
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138
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Probing the interplay between amyloidogenic proteins and membranes using lipid monolayers and bilayers. Adv Colloid Interface Sci 2014; 207:81-92. [PMID: 24200086 DOI: 10.1016/j.cis.2013.10.015] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2013] [Revised: 10/11/2013] [Accepted: 10/13/2013] [Indexed: 11/21/2022]
Abstract
Many degenerative diseases such as Alzheimer's and Parkinson's involve proteins that have a tendency to misfold and aggregate eventually forming amyloid fibers. This review describes the use of monolayers, bilayers, supported membranes, and vesicles as model systems that have helped elucidate the mechanisms and consequences of the interactions between amyloidogenic proteins and membranes. These are twofold: membranes favor the formation of amyloid structures and these induce damage in those membranes. We describe studies that show how interfaces, especially charged ones, favor amyloidogenic protein aggregation by several means. First, surfaces increase the effective protein concentration reducing a three-dimensional system to a two-dimensional one. Second, charged surfaces allow electrostatic interactions with the protein. Anionic lipids as well as rafts, rich in cholesterol and gangliosides, prove to play an especially important role. Finally, these amphipathic systems also offer a hydrophobic environment favoring conformational changes, oligomerization, and eventual formation of mature fibers. In addition, we examine several models for membrane permeabilization: protein pores, leakage induced by extraction of lipids, chaotic pores, and membrane tension, presenting illustrative examples of experimental evidence in support of these models. The picture that emerges from recent work is one where more than one mechanism is in play. Which mechanism prevails depends on the protein, its aggregation state, and the lipid environment in which the interactions occur.
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139
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Sheynis T, Friediger A, Xue WF, Hellewell AL, Tipping KW, Hewitt EW, Radford SE, Jelinek R. Aggregation modulators interfere with membrane interactions of β2-microglobulin fibrils. Biophys J 2014; 105:745-55. [PMID: 23931322 DOI: 10.1016/j.bpj.2013.06.015] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Revised: 05/20/2013] [Accepted: 06/04/2013] [Indexed: 10/26/2022] Open
Abstract
Amyloid fibril accumulation is a pathological hallmark of several devastating disorders, including Alzheimer's disease, prion diseases, type II diabetes, and others. Although the molecular factors responsible for amyloid pathologies have not been deciphered, interactions of misfolded proteins with cell membranes appear to play important roles in these disorders. Despite increasing evidence for the involvement of membranes in amyloid-mediated cytotoxicity, the pursuit for therapeutic strategies has focused on preventing self-assembly of the proteins comprising the amyloid plaques. Here we present an investigation of the impact of fibrillation modulators upon membrane interactions of β2-microglobulin (β2m) fibrils. The experiments reveal that polyphenols (epigallocatechin gallate, bromophenol blue, and resveratrol) and glycosaminoglycans (heparin and heparin disaccharide) differentially affect membrane interactions of β2m fibrils measured by dye-release experiments, fluorescence anisotropy of labeled lipid, and confocal and cryo-electron microscopies. Interestingly, whereas epigallocatechin gallate and heparin prevent membrane damage as judged by these assays, the other compounds tested had little, or no, effect. The results suggest a new dimension to the biological impact of fibrillation modulators that involves interference with membrane interactions of amyloid species, adding to contemporary strategies for combating amyloid diseases that focus on disruption or remodeling of amyloid aggregates.
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Affiliation(s)
- Tania Sheynis
- Department of Chemistry, Ben-Gurion University of the Negev, Beer-Sheva, Israel
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140
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Lorenzen N, Nielsen SB, Buell AK, Kaspersen JD, Arosio P, Vad BS, Paslawski W, Christiansen G, Valnickova-Hansen Z, Andreasen M, Enghild JJ, Pedersen JS, Dobson CM, Knowles TPJ, Otzen DE. The role of stable α-synuclein oligomers in the molecular events underlying amyloid formation. J Am Chem Soc 2014; 136:3859-68. [PMID: 24527756 DOI: 10.1021/ja411577t] [Citation(s) in RCA: 193] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Studies of proteins' formation of amyloid fibrils have revealed that potentially cytotoxic oligomers frequently accumulate during fibril formation. An important question in the context of mechanistic studies of this process is whether or not oligomers are intermediates in the process of amyloid fibril formation, either as precursors of fibrils or as species involved in the fibril elongation process or instead if they are associated with an aggregation process that is distinct from that generating mature fibrils. Here we describe and characterize in detail two well-defined oligomeric species formed by the protein α-synuclein (αSN), whose aggregation is strongly implicated in the development of Parkinson's disease (PD). The two types of oligomers are both formed under conditions where amyloid fibril formation is observed but differ in molecular weight by an order of magnitude. Both possess a degree of β-sheet structure that is intermediate between that of the disordered monomer and the fully structured amyloid fibrils, and both have the capacity to permeabilize vesicles in vitro. The smaller oligomers, estimated to contain ∼30 monomers, are more numerous under the conditions used here than the larger ones, and small-angle X-ray scattering data suggest that they are ellipsoidal with a high degree of flexibility at the interface with solvent. This oligomer population is unable to elongate fibrils and indeed results in an inhibition of the kinetics of amyloid formation in a concentration-dependent manner.
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Affiliation(s)
- Nikolai Lorenzen
- Department of Molecular Biology, Center for Insoluble Protein Structures (inSPIN) and §Department of Chemistry, Interdisciplinary Nanoscience Center (iNANO), Aarhus University , Gustav Wieds Vej 14, 8000 Aarhus C, Denmark
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141
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Bucciantini M, Rigacci S, Stefani M. Amyloid Aggregation: Role of Biological Membranes and the Aggregate-Membrane System. J Phys Chem Lett 2014; 5:517-27. [PMID: 26276603 DOI: 10.1021/jz4024354] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Several human degenerative diseases involve amyloidogenic peptides/proteins with high conformational plasticity and propensity to self-aggregate into polymeric fibrillar assemblies sharing the cross-β structure and endowed with cytotoxic potential. Although the mechanisms of amyloid growth and toxicity are not fully understood, a common property of amyloids is their ability to interact with lipid bilayers disturbing membrane integrity. Lipid bilayers can also act as conformational catalysts, favoring protein misfolding and inducing the growth of aggregation nuclei, early oligomers, and mature fibrils with specific biophysical, structural, and toxicity features. This Perspective will highlight these effects in the context of a membrane-oligomer system where the conformational/biophysical features of either component affect those of the other. In this context, we will highlight the modulation of the protein-cell surface interaction by the content of membrane cholesterol and gangliosides, notably GM1. In particular, we will discuss data that indicate how these interactions affect the structural and stability properties of both protein and bilayers as well as the final cytotoxic effect. Our goal is to propose shared membrane-based mechanisms that could apply to any amyloidogenic peptide/protein, providing a biochemical background for amyloid growth and toxicity.
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Affiliation(s)
- Monica Bucciantini
- †Department of Biomedical Experimental and Clinical Sciences and Research Centre on the Molecular Basis of Neurodegeneration, University of Florence, V.le Morgagni 50, 50134 Florence, Italy
| | - Stefania Rigacci
- †Department of Biomedical Experimental and Clinical Sciences and Research Centre on the Molecular Basis of Neurodegeneration, University of Florence, V.le Morgagni 50, 50134 Florence, Italy
| | - Massimo Stefani
- †Department of Biomedical Experimental and Clinical Sciences and Research Centre on the Molecular Basis of Neurodegeneration, University of Florence, V.le Morgagni 50, 50134 Florence, Italy
- ‡National Institute of Biostructures and Biosystems (INBB), Viale Medaglie d'Oro 305, 00136 Rome, Italy
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142
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Relini A, Marano N, Gliozzi A. Misfolding of amyloidogenic proteins and their interactions with membranes. Biomolecules 2013; 4:20-55. [PMID: 24970204 PMCID: PMC4030986 DOI: 10.3390/biom4010020] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Revised: 12/13/2013] [Accepted: 12/17/2013] [Indexed: 01/07/2023] Open
Abstract
In this paper, we discuss amyloidogenic proteins, their misfolding, resulting structures, and interactions with membranes, which lead to membrane damage and subsequent cell death. Many of these proteins are implicated in serious illnesses such as Alzheimer’s disease and Parkinson’s disease. Misfolding of amyloidogenic proteins leads to the formation of polymorphic oligomers and fibrils. Oligomeric aggregates are widely thought to be the toxic species, however, fibrils also play a role in membrane damage. We focus on the structure of these aggregates and their interactions with model membranes. Study of interactions of amlyoidogenic proteins with model and natural membranes has shown the importance of the lipid bilayer in protein misfolding and aggregation and has led to the development of several models for membrane permeabilization by the resulting amyloid aggregates. We discuss several of these models: formation of structured pores by misfolded amyloidogenic proteins, extraction of lipids, interactions with receptors in biological membranes, and membrane destabilization by amyloid aggregates perhaps analogous to that caused by antimicrobial peptides.
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Affiliation(s)
- Annalisa Relini
- Department of Physics, University of Genoa, Genoa 16146, Italy.
| | - Nadia Marano
- Department of Physics, University of Genoa, Genoa 16146, Italy.
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143
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Depletion of spleen macrophages delays AA amyloid development: a study performed in the rapid mouse model of AA amyloidosis. PLoS One 2013; 8:e79104. [PMID: 24236094 PMCID: PMC3827313 DOI: 10.1371/journal.pone.0079104] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2013] [Accepted: 09/18/2013] [Indexed: 11/19/2022] Open
Abstract
AA amyloidosis is a systemic disease that develops secondary to chronic inflammatory diseases Macrophages are often found in the vicinity of amyloid deposits and considered to play a role in both formation and degradation of amyloid fibrils. In spleen reside at least three types of macrophages, red pulp macrophages (RPM), marginal zone macrophages (MZM), metallophilic marginal zone macrophages (MMZM). MMZM and MZM are located in the marginal zone and express a unique collection of scavenger receptors that are involved in the uptake of blood-born particles. The murine AA amyloid model that resembles the human form of the disease has been used to study amyloid effects on different macrophage populations. Amyloid was induced by intravenous injection of amyloid enhancing factor and subcutaneous injections of silver nitrate and macrophages were identified with specific antibodies. We show that MZMs are highly sensitive to amyloid and decrease in number progressively with increasing amyloid load. Total area of MMZMs is unaffected by amyloid but cells are activated and migrate into the white pulp. In a group of mice spleen macrophages were depleted by an intravenous injection of clodronate filled liposomes. Subsequent injections of AEF and silver nitrate showed a sustained amyloid development. RPMs that constitute the majority of macrophages in spleen, appear insensitive to amyloid and do not participate in amyloid formation.
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144
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Hellstrand E, Nowacka A, Topgaard D, Linse S, Sparr E. Membrane lipid co-aggregation with α-synuclein fibrils. PLoS One 2013; 8:e77235. [PMID: 24146972 PMCID: PMC3795653 DOI: 10.1371/journal.pone.0077235] [Citation(s) in RCA: 93] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2013] [Accepted: 08/30/2013] [Indexed: 11/27/2022] Open
Abstract
Amyloid deposits from several human diseases have been found to contain membrane lipids. Co-aggregation of lipids and amyloid proteins in amyloid aggregates, and the related extraction of lipids from cellular membranes, can influence structure and function in both the membrane and the formed amyloid deposit. Co-aggregation can therefore have important implications for the pathological consequences of amyloid formation. Still, very little is known about the mechanism behind co-aggregation and molecular structure in the formed aggregates. To address this, we study in vitro co-aggregation by incubating phospholipid model membranes with the Parkinson's disease-associated protein, α-synuclein, in monomeric form. After aggregation, we find spontaneous uptake of phospholipids from anionic model membranes into the amyloid fibrils. Phospholipid quantification, polarization transfer solid-state NMR and cryo-TEM together reveal co-aggregation of phospholipids and α-synuclein in a saturable manner with a strong dependence on lipid composition. At low lipid to protein ratios, there is a close association of phospholipids to the fibril structure, which is apparent from reduced phospholipid mobility and morphological changes in fibril bundling. At higher lipid to protein ratios, additional vesicles adsorb along the fibrils. While interactions between lipids and amyloid-protein are generally discussed within the perspective of different protein species adsorbing to and perturbing the lipid membrane, the current work reveals amyloid formation in the presence of lipids as a co-aggregation process. The interaction leads to the formation of lipid-protein co-aggregates with distinct structure, dynamics and morphology compared to assemblies formed by either lipid or protein alone.
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Affiliation(s)
- Erik Hellstrand
- Division of Biophysical Chemistry, Center of Chemistry and Chemical Engineering, Lund University, Lund, Sweden
| | - Agnieszka Nowacka
- Division of Physical Chemistry, Center of Chemistry and Chemical Engineering, Lund University, Lund, Sweden
| | - Daniel Topgaard
- Division of Physical Chemistry, Center of Chemistry and Chemical Engineering, Lund University, Lund, Sweden
| | - Sara Linse
- Division of Biochemistry, Center of Chemistry and Chemical Engineering, Lund University, Lund, Sweden
| | - Emma Sparr
- Division of Physical Chemistry, Center of Chemistry and Chemical Engineering, Lund University, Lund, Sweden
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145
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Thapa A, Vernon BC, De la Peña K, Soliz G, Moreno HA, López GP, Chi EY. Membrane-mediated neuroprotection by curcumin from amyloid-β-peptide-induced toxicity. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:11713-11723. [PMID: 24004419 DOI: 10.1021/la4020459] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Amyloid-β peptide (Aβ)-membrane interactions have been implicated in the formation of toxic oligomers that permeabilize membranes, allowing an influx of calcium ions and triggering cell death in the pathogenesis of Alzheimer's disease (AD). Curcumin, a small dietary polyphenolic molecule, has been shown to reduce Aβ-induced toxicity and AD pathology. We investigate here the effect of curcumin on Aβ40-induced toxicity in cultured human neuroblastoma SH-SY5Y cells and test a novel neuroprotection mechanism in which curcumin reduces Aβ-membrane interactions and attenuates Aβ-induced membrane disruptions. Predominantly monomeric Aβ40 exerts toxicity toward SH-SY5Y cells and has been shown to insert spontaneously into anionic lipid monolayers at the air/water interface, resulting in the misfolding and assembly of Aβ into β-sheet-enriched oligomers. Concomitantly, membrane morphology and lipid packing are disrupted. Curcumin dose-dependently ameliorates Aβ-induced neurotoxicity and reduces either the rate or extent of Aβ insertion into anionic lipid monolayers. Moreover, curcumin reduces Aβ-induced dye leakage from lipid-bilayer-covered, dye-loaded, porous silica microspheres. Because curcumin neither affects the inherent surface activity of Aβ nor modifies the membrane properties, it reduces Aβ insertion by directly attenuating Aβ-membrane interactions and reducing Aβ-induced membrane disruption. Although the exact molecular mechanism of curcumin's membrane protective effect remains unclear, this effect could in part contribute to curcumin's neuroprotective effect with respect to Aβ-induced toxicity. Our work reveals a novel molecular mechanism by which curcumin reduces Aβ-related pathology and toxicity and suggests a therapeutic strategy for preventing or treating AD by targeting the inhibition of Aβ-induced membrane disruption.
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Affiliation(s)
- Arjun Thapa
- Department of Chemical and Nuclear Engineering and the Center for Biomedical Engineering, University of New Mexico , Albuquerque, New Mexico 87131, United States
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146
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Mulligan VK, Chakrabartty A. Protein misfolding in the late-onset neurodegenerative diseases: Common themes and the unique case of amyotrophic lateral sclerosis. Proteins 2013; 81:1285-303. [DOI: 10.1002/prot.24285] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2012] [Revised: 02/27/2013] [Accepted: 02/28/2013] [Indexed: 12/12/2022]
Affiliation(s)
| | - Avijit Chakrabartty
- Department of Biochemistry; Toronto Ontario M5G 1L7 Canada
- Department of Medical Biophysics; University of Toronto; Toronto Ontario M5G 1L7 Canada
- Campbell Family Institute for Cancer Research, Ontario Cancer Institute/University Health Network; Toronto Ontario M5G 1L7 Canada
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147
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Jang H, Connelly L, Arce FT, Ramachandran S, Lal R, Kagan BL, Nussinov R. Alzheimer's disease: which type of amyloid-preventing drug agents to employ? Phys Chem Chem Phys 2013; 15:8868-77. [PMID: 23450150 PMCID: PMC3663909 DOI: 10.1039/c3cp00017f] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The current paradigm in the amyloid hypothesis brands small β-amyloid (Aβ) oligomers as the toxic species in Alzheimer's disease (AD). These oligomers are fibril-like; contain β-sheet structure, and present exposed hydrophobic surface. Oligomers with this motif are capable of penetrating the cell membrane, gathering to form toxic ion channels. Current agents suppressing precursor Aβ cleavage have only met partial success; and to date, those targeting the peptides and their assemblies in the aqueous environment of the extracellular space largely fail in clinical trials. One possible reason is failure to reach membrane-embedded targets of disease-'infected' cells. Here we provide an overview, point to the need to account for the lipid environment when aiming to prevent the formation of toxic channels, and propose a combination therapy to target the species spectrum.
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Affiliation(s)
- Hyunbum Jang
- Center for Cancer Research, Nanobiology Program, Basic Science Program, SAIC-Frederick, Inc., National Cancer Institute, Frederick, Maryland 21702, USA
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148
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Exceptional rigidity and biomechanics of amyloid revealed by 4D electron microscopy. Proc Natl Acad Sci U S A 2013; 110:10976-81. [PMID: 23784773 DOI: 10.1073/pnas.1309690110] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Amyloid is an important class of proteinaceous material because of its close association with protein misfolding disorders such as Alzheimer's disease and type II diabetes. Although the degree of stiffness of amyloid is critical to the understanding of its pathological and biological functions, current estimates of the rigidity of these β-sheet-rich protein aggregates range from soft (10(8) Pa) to hard (10(10) Pa) depending on the method used. Here, we use time-resolved 4D EM to directly and noninvasively measure the oscillatory dynamics of freestanding, self-supporting amyloid beams and their rigidity. The dynamics of a single structure, not an ensemble, were visualized in space and time by imaging in the microscope an amyloid-dye cocrystal that, upon excitation, converts light into mechanical work. From the oscillatory motion, together with tomographic reconstructions of three studied amyloid beams, we determined the Young modulus of these highly ordered, hydrogen-bonded β-sheet structures. We find that amyloid materials are very stiff (10(9) Pa). The potential biological relevance of the deposition of such a highly rigid biomaterial in vivo are discussed.
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149
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Brender JR, Heyl DL, Samisetti S, Kotler SA, Osborne JM, Pesaru RR, Ramamoorthy A. Membrane disordering is not sufficient for membrane permeabilization by islet amyloid polypeptide: studies of IAPP(20-29) fragments. Phys Chem Chem Phys 2013; 15:8908-15. [PMID: 23493863 DOI: 10.1039/c3cp44696d] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A key factor in the development of type II diabetes is the loss of insulin-producing beta-cells. Human islet amyloid polypeptide protein (human-IAPP) is believed to play a crucial role in this process by forming small aggregates that exhibit toxicity by disrupting the cell membrane. The actual mechanism of membrane disruption is complex and appears to involve an early component before fiber formation and a later component associated with fiber formation on the membrane. By comparing the peptide-lipid interactions derived from solid-state NMR experiments of two IAPP fragments that cause membrane disordering to IAPP derived peptides known to cause significant early membrane permeabilization, we show here that membrane disordering is not likely to be sufficient by itself to cause the early membrane permeabilization observed by IAPP, and may play a lesser role in IAPP membrane disruption than expected.
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Affiliation(s)
- Jeffrey R Brender
- Biophysics and Department of Chemistry, University of Michigan, Ann Arbor, MI 48109-1055, USA
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150
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Salvatella X. Structural aspects of amyloid formation. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2013; 117:73-101. [PMID: 23663966 DOI: 10.1016/b978-0-12-386931-9.00004-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Amyloid fibrils are highly organized and generally insoluble protein aggregates rich in β secondary structure that can be formed by a wide range of sequences. They have been the object of intense scrutiny because their formation has been associated with a number of neurodegenerative disorders such as Alzheimer's, Parkinson's, Huntington's, and Creutzfeldt-Jakob's diseases. As a consequence of these efforts, much is now known about the properties of proteins that render them prone to form amyloid fibrils, about the mechanism of fibrillation, about the molecular structures of the fibrils, and about the forces that stabilize them. The relationship between the structural properties of the monomeric protein and those of the corresponding aggregate has been, in particular, intensively studied. In this chapter, we will provide an account of current knowledge on this intriguing relationship and provide the reader with key references about this topic.
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