1
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Palladini G, Liedtke M, Zago W, Dolan P, Kinney GG, Gertz MA. The mechanism of action, pharmacological characteristics, and clinical utility of the amyloid depleter birtamimab for the potential treatment of AL amyloidosis. Leuk Lymphoma 2024; 65:1068-1078. [PMID: 38600883 DOI: 10.1080/10428194.2024.2337803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Accepted: 03/27/2024] [Indexed: 04/12/2024]
Abstract
Amyloid light chain (AL) amyloidosis is a progressive plasma cell disorder caused by amyloid deposition resulting in organ damage and failure. Current standard-of-care treatments target clonal plasma cells, the source of misfolded light chains (amyloid precursors), yet only half of patients with advanced disease survive ≥6 months. The amyloid depleter birtamimab is an investigational humanized monoclonal antibody that binds misfolded κ and λ light chains with high specificity and was designed to neutralize soluble toxic light chain aggregates and promote phagocytic clearance of deposited amyloid. Post hoc analyses from the Phase 3 VITAL trial suggested birtamimab plus standard of care confers a survival benefit in patients with advanced (Mayo Stage IV) AL amyloidosis. AFFIRM-AL (NCT04973137), a Phase 3 confirmatory trial of birtamimab plus standard of care in patients with Mayo Stage IV AL amyloidosis, is ongoing. This review summarizes birtamimab's mechanism of action, attributes, and potential clinical utility.
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Affiliation(s)
- Giovanni Palladini
- Department of Molecular Medicine, University of Pavia, Pavia, Italy
- Amyloidosis Research and Treatment Center, Fondazione IRCCS, Policlinico San Matteo, Pavia, Italy
| | | | | | - Phil Dolan
- Prothena Biosciences Inc, Brisbane, CA, USA
| | | | - Morie A Gertz
- Division of Hematology, Department of Internal Medicine, Mayo Clinic, Rochester, MN, USA
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2
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Maerivoet A, Price R, Galmiche C, Scott-Tucker A, Kennedy J, Crabbe T, Antonyuk S, Madine J. Enhanced stabilisation and reduced fibril forming potential of an amyloidogenic light chain using a variable heavy domain to mimic the homodimer complex. FEBS J 2024. [PMID: 38982771 DOI: 10.1111/febs.17223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Revised: 05/13/2024] [Accepted: 06/26/2024] [Indexed: 07/11/2024]
Abstract
Light chain amyloidosis (AL), is classified as a plasma cell dyscrasia, whereby a mutant plasma cell multiplies uncontrollably and secretes enormous amounts of immunoglobulin-free light chain (FLC) fragments. These FLCs undergo a process of misfolding and aggregation into amyloid fibrils, that can cause irreversible system-wide damage. Current treatments that focus on depleting the underlying plasma cell clone are often poorly tolerated, particularly in patients with severe cardiac involvement, meaning patient prognosis is poor. An alternative treatment approach currently being explored is the inhibition of FLC aggregation by stabilisation of the native conformer. Here, we aimed to identify and characterise antibody fragments that target FLC domains and promote their stabilisation. Using phage-display screening methods, we identified a variable heavy (VH) domain, termed VH1, targeted towards the FLC. Using differential scanning fluorimetry and surface plasmon resonance, VH1 was characterised to bind and kinetically stabilise an amyloidogenic FLC, whereby a > 5.5 °C increase in thermal stability was noted. This improved stability corresponded to the inhibition of fibril formation, where 10 : 1 LC : VH1 concentration reduced aggregation to baseline levels. X-ray crystallographic structures of the LC : VH1 complex at atomic resolution revealed binding in a 1 : 1 ratio, mimicking the dimeric antigen binding sites of the native immunoglobulin molecule and the native LC homodimer.
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Affiliation(s)
- Alana Maerivoet
- Institute of Systems, Molecular and Integrative Biology, University of Liverpool, UK
| | - Rebecca Price
- Institute of Systems, Molecular and Integrative Biology, University of Liverpool, UK
| | | | | | | | | | - Svetlana Antonyuk
- Institute of Systems, Molecular and Integrative Biology, University of Liverpool, UK
| | - Jillian Madine
- Institute of Systems, Molecular and Integrative Biology, University of Liverpool, UK
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3
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Desantis F, Miotto M, Milanetti E, Ruocco G, Di Rienzo L. Computational evidences of a misfolding event in an aggregation-prone light chain preceding the formation of the non-native pathogenic dimer. Proteins 2024; 92:797-807. [PMID: 38314653 DOI: 10.1002/prot.26672] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Revised: 01/09/2024] [Accepted: 01/19/2024] [Indexed: 02/06/2024]
Abstract
Antibody light chain amyloidosis is a disorder in which protein aggregates, mainly composed of immunoglobulin light chains, deposit in diverse tissues impairing the correct functioning of organs. Interestingly, due to the high susceptibility of antibodies to mutations, AL amyloidosis appears to be strongly patient-specific. Indeed, every patient will display their own mutations that will make the proteins involved prone to aggregation thus hindering the study of this disease on a wide scale. In this framework, determining the molecular mechanisms that drive the aggregation could pave the way to the development of patient-specific therapeutics. Here, we focus on a particular patient-derived light chain, which has been experimentally characterized. We investigated the early phases of the aggregation pathway through extensive full-atom molecular dynamics simulations, highlighting a structural rearrangement and the exposure of two hydrophobic regions in the aggregation-prone species. Next, we moved to consider the pathological dimerization process through docking and molecular dynamics simulations, proposing a dimeric structure as a candidate pathological first assembly. Overall, our results shed light on the first phases of the aggregation pathway for a light chain at an atomic level detail, offering new structural insights into the corresponding aggregation process.
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Affiliation(s)
- Fausta Desantis
- The Open University Affiliated Research Centre at Istituto Italiano di Tecnologia, Genova, Italy
- Istituto Italiano di Tecnologia (IIT), Center for Life Nano & Neuro Science, Roma, Italy
| | - Mattia Miotto
- Istituto Italiano di Tecnologia (IIT), Center for Life Nano & Neuro Science, Roma, Italy
| | - Edoardo Milanetti
- Istituto Italiano di Tecnologia (IIT), Center for Life Nano & Neuro Science, Roma, Italy
- Department of Physics, Sapienza University of Rome, Rome, Italy
| | - Giancarlo Ruocco
- Istituto Italiano di Tecnologia (IIT), Center for Life Nano & Neuro Science, Roma, Italy
- Department of Physics, Sapienza University of Rome, Rome, Italy
| | - Lorenzo Di Rienzo
- Istituto Italiano di Tecnologia (IIT), Center for Life Nano & Neuro Science, Roma, Italy
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4
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Wong S, West ME, Morgan GJ. Kinetic evidence for multiple aggregation pathways in antibody light chain variable domains. Protein Sci 2024; 33:e4871. [PMID: 38100259 PMCID: PMC10868443 DOI: 10.1002/pro.4871] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 12/01/2023] [Accepted: 12/11/2023] [Indexed: 12/17/2023]
Abstract
Aggregation of antibody light chain proteins is associated with the progressive disease light chain amyloidosis. Patient-derived amyloid fibrils are formed from light chain variable domain residues in non-native conformations, highlighting a requirement that light chains unfold from their native structures in order to aggregate. However, mechanistic studies of amyloid formation have primarily focused on the self-assembly of natively unstructured peptides, and the role of native state unfolding is less well understood. Using a well-studied light chain variable domain protein known as WIL, which readily aggregates in vitro under conditions where the native state predominates, we asked how the protein concentration and addition of pre-formed fibril "seeds" alter the kinetics of aggregation. Monitoring aggregation with thioflavin T fluorescence revealed a distinctly non-linear dependence on concentration, with a maximum aggregation rate observed at 8 μM protein. This behavior is consistent with formation of alternate aggregate structures in the early phases of amyloid formation. Addition of N- or C-terminal peptide tags, which did not greatly affect the folding or stability of the protein, altered the concentration dependence of aggregation. Aggregation rates increased in the presence of pre-formed seeds, but this effect did not eliminate the delay before aggregation and became saturated when the proportion of seeds added was greater than 1 in 1600. The complexity of aggregation observed in vitro highlights how multiple species may contribute to amyloid pathology in patients.
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Affiliation(s)
- Sherry Wong
- Boston University Amyloidosis Center, Boston University Chobanian and Avedisian School of Medicine, Boston, Massachusetts, USA
| | - Madeline E West
- Boston University Amyloidosis Center, Boston University Chobanian and Avedisian School of Medicine, Boston, Massachusetts, USA
| | - Gareth J Morgan
- Boston University Amyloidosis Center, Boston University Chobanian and Avedisian School of Medicine, Boston, Massachusetts, USA
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5
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Goldis R, Kaplan B, Arad M, Dispenzieri A, Dasari S, Kukuy OL, Simon AJ, Dori A, Shavit-Stein E, Ziv T, Murray D, Kourelis T, Gertz MA, Dominissini D, Magen H, Muchtar E. Amino acid sequence homology of monoclonal serum free light chain dimers and tissue deposited light chains in AL amyloidosis: a pilot study. Clin Chem Lab Med 2024; 62:464-471. [PMID: 37747270 DOI: 10.1515/cclm-2023-0591] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Accepted: 09/12/2023] [Indexed: 09/26/2023]
Abstract
OBJECTIVES Diagnosis of light chain amyloidosis (AL) requires demonstration of amyloid deposits in a tissue biopsy followed by appropriate typing. Previous studies demonstrated increased dimerization of monoclonal serum free light chains (FLCs) as a pathological feature of AL. To further examine the pathogenicity of FLC, we aimed at testing amino acid sequence homology between circulating and deposited light chains (LCs). METHODS Matched tissue biopsy and serum of 10 AL patients were subjected to tissue proteomic amyloid typing and nephelometric FLC assay, respectively. Serum FLC monomers (M) and dimers (D) were analyzed by Western blotting (WB) and mass spectrometry (MS). RESULTS WB of serum FLCs showed predominance of either κ or λ type, in agreement with the nephelometric assay data. Abnormal FLC M-D patterns typical of AL amyloidosis were demonstrated in 8 AL-λ patients and in one of two AL-κ patients: increased levels of monoclonal FLC dimers, high D/M ratio values of involved FLCs, and high ratios of involved to uninvolved dimeric FLCs. MS of serum FLC dimers showed predominant constant domain sequences, in concordance with the tissue proteomic amyloid typing. Most importantly, variable domain sequence homology between circulating and deposited LC species was demonstrated, mainly in AL-λ cases. CONCLUSIONS This is the first study to demonstrate homology between circulating FLCs and tissue-deposited LCs in AL-λ amyloidosis. The applied methodology can facilitate studying the pathogenicity of circulating FLC dimers in AL amyloidosis. The study also highlights the potential of FLC monomer and dimer analysis as a non-invasive screening tool for this disease.
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Affiliation(s)
- Rivka Goldis
- Department of Neurology, Sheba Medical Center, Ramat Gan, Israel
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Batia Kaplan
- Institute of Hematology and Sheba Cancer Research Center, Sheba Medical Center, Ramat Gan, Israel
| | - Michael Arad
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
- Heart Failure Institute, Leviev Heart Center, Sheba Medical Center, Ramat Gan, Israel
| | | | - Surendra Dasari
- Department of Health Sciences Research, Mayo Clinic, Rochester, MN, USA
| | - Olga Lesya Kukuy
- Institute of Nephrology and Hypertension, Sheba Medical Center, Ramat Gan, Israel
| | - Amos J Simon
- Institute of Hematology and Sheba Cancer Research Center, Sheba Medical Center, Ramat Gan, Israel
| | - Amir Dori
- Department of Neurology, Sheba Medical Center, Ramat Gan, Israel
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Efrat Shavit-Stein
- Department of Neurology, Sheba Medical Center, Ramat Gan, Israel
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Tamar Ziv
- Smoler Protein Center, Faculty of Biology, Technion - Israel Institute of Technology, Haifa, Israel
| | - David Murray
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
| | | | - Morie A Gertz
- Division of Hematology, Mayo Clinic, Rochester, MN, USA
| | - Dan Dominissini
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
- The Genomics Unit, Sheba Cancer Research Center, Sheba Medical Center, Ramat Gan, Israel
- Wohl Institute of Translational Medicine, Sheba Medical Center, Ramat Gan, Israel
| | - Hila Magen
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
- Multiple Myeloma Unit, Hematology Department, Sheba Medical Center, Ramat Gan, Israel
| | - Eli Muchtar
- Division of Hematology, Mayo Clinic, Rochester, MN, USA
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6
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Wong S, West ME, Morgan GJ. Kinetic evidence for multiple aggregation pathways in antibody light chain variable domains. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.28.555139. [PMID: 37693524 PMCID: PMC10491100 DOI: 10.1101/2023.08.28.555139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/12/2023]
Abstract
Aggregation of antibody light chain proteins is associated with the progressive disease light chain amyloidosis. Patient-derived amyloid fibrils are formed from light chain variable domain residues in non-native conformations, highlighting a requirement that light chains unfold from their native structures in order to aggregate. However, mechanistic studies of amyloid formation have primarily focused on the self-assembly of natively unstructured peptides, and the role of native state unfolding is less well understood. Using a well-studied light chain variable domain protein known as WIL, which readily aggregates in vitro under conditions where the native state predominates, we asked how the protein concentration and addition of pre-formed fibril "seeds" alter the kinetics of aggregation. Monitoring aggregation with thioflavin T fluorescence revealed a distinctly non-linear dependence on concentration, with a maximum aggregation rate observed at 8 μM protein. This behavior is consistent with formation of alternate aggregate structures in the early phases of amyloid formation. Addition of N- or C-terminal peptide tags, which did not greatly affect the folding or stability of the protein, altered the concentration dependence of aggregation. Aggregation rates increased in the presence of pre-formed seeds, but this effect did not eliminate the delay before aggregation and became saturated when the proportion of seeds added was greater than 1 in 1600. The complexity of aggregation observed in vitro highlights how multiple species may contribute to amyloid pathology in patients.
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Affiliation(s)
- Sherry Wong
- Boston University Amyloidosis Center, Boston University Chobanian & Avedisian School of Medicine, Boston, MA, USA
| | - Madeline E West
- Boston University Amyloidosis Center, Boston University Chobanian & Avedisian School of Medicine, Boston, MA, USA
| | - Gareth J Morgan
- Boston University Amyloidosis Center, Boston University Chobanian & Avedisian School of Medicine, Boston, MA, USA
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7
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Del Pozo-Yauner L, Herrera GA, Perez Carreon JI, Turbat-Herrera EA, Rodriguez-Alvarez FJ, Ruiz Zamora RA. Role of the mechanisms for antibody repertoire diversification in monoclonal light chain deposition disorders: when a friend becomes foe. Front Immunol 2023; 14:1203425. [PMID: 37520549 PMCID: PMC10374031 DOI: 10.3389/fimmu.2023.1203425] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Accepted: 06/20/2023] [Indexed: 08/01/2023] Open
Abstract
The adaptive immune system of jawed vertebrates generates a highly diverse repertoire of antibodies to meet the antigenic challenges of a constantly evolving biological ecosystem. Most of the diversity is generated by two mechanisms: V(D)J gene recombination and somatic hypermutation (SHM). SHM introduces changes in the variable domain of antibodies, mostly in the regions that form the paratope, yielding antibodies with higher antigen binding affinity. However, antigen recognition is only possible if the antibody folds into a stable functional conformation. Therefore, a key force determining the survival of B cell clones undergoing somatic hypermutation is the ability of the mutated heavy and light chains to efficiently fold and assemble into a functional antibody. The antibody is the structural context where the selection of the somatic mutations occurs, and where both the heavy and light chains benefit from protective mechanisms that counteract the potentially deleterious impact of the changes. However, in patients with monoclonal gammopathies, the proliferating plasma cell clone may overproduce the light chain, which is then secreted into the bloodstream. This places the light chain out of the protective context provided by the quaternary structure of the antibody, increasing the risk of misfolding and aggregation due to destabilizing somatic mutations. Light chain-derived (AL) amyloidosis, light chain deposition disease (LCDD), Fanconi syndrome, and myeloma (cast) nephropathy are a diverse group of diseases derived from the pathologic aggregation of light chains, in which somatic mutations are recognized to play a role. In this review, we address the mechanisms by which somatic mutations promote the misfolding and pathological aggregation of the light chains, with an emphasis on AL amyloidosis. We also analyze the contribution of the variable domain (VL) gene segments and somatic mutations on light chain cytotoxicity, organ tropism, and structure of the AL fibrils. Finally, we analyze the most recent advances in the development of computational algorithms to predict the role of somatic mutations in the cardiotoxicity of amyloidogenic light chains and discuss the challenges and perspectives that this approach faces.
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Affiliation(s)
- Luis Del Pozo-Yauner
- Department of Pathology, University of South Alabama-College of Medicine, Mobile, AL, United States
| | - Guillermo A. Herrera
- Department of Pathology, University of South Alabama-College of Medicine, Mobile, AL, United States
| | | | - Elba A. Turbat-Herrera
- Department of Pathology, University of South Alabama-College of Medicine, Mobile, AL, United States
- Mitchell Cancer Institute, University of South Alabama-College of Medicine, Mobile, AL, United States
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8
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Pradhan T, Sarkar R, Meighen-Berger KM, Feige MJ, Zacharias M, Reif B. Mechanistic insights into the aggregation pathway of the patient-derived immunoglobulin light chain variable domain protein FOR005. Nat Commun 2023; 14:3755. [PMID: 37353525 PMCID: PMC10290123 DOI: 10.1038/s41467-023-39280-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2022] [Accepted: 06/05/2023] [Indexed: 06/25/2023] Open
Abstract
Systemic antibody light chain (AL) amyloidosis is characterized by deposition of amyloid fibrils. Prior to fibril formation, soluble oligomeric AL protein has a direct cytotoxic effect on cardiomyocytes. We focus on the patient derived λ-III AL variable domain FOR005 which is mutated at five positions with respect to the closest germline protein. Using solution-state NMR spectroscopy, we follow the individual steps involved in protein misfolding from the native to the amyloid fibril state. Unfavorable mutations in the complementary determining regions introduce a strain in the native protein structure which yields partial unfolding. Driven by electrostatic interactions, the protein converts into a high molecular weight, oligomeric, molten globule. The high local concentration of aggregation prone regions in the oligomer finally catalyzes the conversion into fibrils. The topology is determined by balanced electrostatic interactions in the fibril core implying a 180° rotational switch of the beta-sheets around the conserved disulfide bond.
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Affiliation(s)
- Tejaswini Pradhan
- Bavarian NMR Center (BNMRZ), Department of Bioscience, TUM School of Natural Sciences, Technical University Munich, Lichtenbergstr. 4, 85747, Garching, Germany
- Institute of Structural Biology (STB), Helmholtz-Zentrum München (HMGU), Ingolstädter Landstr. 1, 85764, Neuherberg, Germany
| | - Riddhiman Sarkar
- Bavarian NMR Center (BNMRZ), Department of Bioscience, TUM School of Natural Sciences, Technical University Munich, Lichtenbergstr. 4, 85747, Garching, Germany
- Institute of Structural Biology (STB), Helmholtz-Zentrum München (HMGU), Ingolstädter Landstr. 1, 85764, Neuherberg, Germany
| | - Kevin M Meighen-Berger
- Center for Functional Protein Assemblies (CPA), Department of Bioscience, TUM School of Natural Sciences, Technical University Munich, Ernst-Otto-Fischer-Straße 8, 85748, Garching, Germany
| | - Matthias J Feige
- Center for Functional Protein Assemblies (CPA), Department of Bioscience, TUM School of Natural Sciences, Technical University Munich, Ernst-Otto-Fischer-Straße 8, 85748, Garching, Germany
| | - Martin Zacharias
- Center for Functional Protein Assemblies (CPA), Department of Bioscience, TUM School of Natural Sciences, Technical University Munich, Ernst-Otto-Fischer-Straße 8, 85748, Garching, Germany
| | - Bernd Reif
- Bavarian NMR Center (BNMRZ), Department of Bioscience, TUM School of Natural Sciences, Technical University Munich, Lichtenbergstr. 4, 85747, Garching, Germany.
- Institute of Structural Biology (STB), Helmholtz-Zentrum München (HMGU), Ingolstädter Landstr. 1, 85764, Neuherberg, Germany.
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9
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Meunier-Carmenate Y, Valdés-García G, Maya-Martinez R, French-Pacheco L, Fernández-Silva A, González-Onofre Y, Millan-Pacheco C, Pastor N, Amero C. Unfolding and Aggregation Pathways of Variable Domains from Immunoglobulin Light Chains. Biochemistry 2023; 62:1000-1011. [PMID: 36802343 DOI: 10.1021/acs.biochem.2c00704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
Light chain amyloidosis is the most common form of systemic amyloidosis. This disease is caused by the formation and deposition of amyloid fibers made from immunoglobulin light chains. Environmental conditions such as pH and temperature can affect protein structure and induce the development of these fibers. Several studies have shed light on the native state, stability, dynamics, and final amyloid state of these proteins; however, the initiation process and the fibril formation pathway remain poorly understood structurally and kinetically. To study this, we analyzed the unfolding and aggregation process of the 6aJL2 protein under acidic conditions, with temperature changes, and upon mutation, using biophysical and computational techniques. Our results suggest that the differences in amyloidogenicity displayed by 6aJL2 under these conditions are caused by traversing different aggregation pathways, including unfolded intermediates and the formation of oligomers.
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Affiliation(s)
- Yadira Meunier-Carmenate
- Laboratorio de Bioquímica y Resonancia Magnética Nuclear, Centro de Investigaciones Químicas-IICBA, Universidad Autónoma del Estado de Morelos, Cuernavaca 62209, Morelos, Mexico
| | - Gilberto Valdés-García
- Centro de Investigacion en Dinámica Celular-IICBA, Universidad Autónoma del Estado de Morelos, Cuernavaca 62209, Morelos, Mexico
| | - Roberto Maya-Martinez
- Laboratorio de Bioquímica y Resonancia Magnética Nuclear, Centro de Investigaciones Químicas-IICBA, Universidad Autónoma del Estado de Morelos, Cuernavaca 62209, Morelos, Mexico
| | - Leidys French-Pacheco
- Laboratorio de Bioquímica y Resonancia Magnética Nuclear, Centro de Investigaciones Químicas-IICBA, Universidad Autónoma del Estado de Morelos, Cuernavaca 62209, Morelos, Mexico
| | - Arline Fernández-Silva
- Laboratorio de Bioquímica y Resonancia Magnética Nuclear, Centro de Investigaciones Químicas-IICBA, Universidad Autónoma del Estado de Morelos, Cuernavaca 62209, Morelos, Mexico
| | - Yoselin González-Onofre
- Laboratorio de Bioquímica y Resonancia Magnética Nuclear, Centro de Investigaciones Químicas-IICBA, Universidad Autónoma del Estado de Morelos, Cuernavaca 62209, Morelos, Mexico
| | - Cesar Millan-Pacheco
- Facultad de Farmacia, Universidad Autónoma del Estado de Morelos, Cuernavaca 62209, Morelos, Mexico
| | - Nina Pastor
- Centro de Investigacion en Dinámica Celular-IICBA, Universidad Autónoma del Estado de Morelos, Cuernavaca 62209, Morelos, Mexico
| | - Carlos Amero
- Laboratorio de Bioquímica y Resonancia Magnética Nuclear, Centro de Investigaciones Químicas-IICBA, Universidad Autónoma del Estado de Morelos, Cuernavaca 62209, Morelos, Mexico
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10
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Absmeier RM, Rottenaicher GJ, Svilenov HL, Kazman P, Buchner J. Antibodies gone bad - the molecular mechanism of light chain amyloidosis. FEBS J 2023; 290:1398-1419. [PMID: 35122394 DOI: 10.1111/febs.16390] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 01/19/2022] [Accepted: 02/03/2022] [Indexed: 12/19/2022]
Abstract
Light chain amyloidosis (AL) is a systemic disease in which abnormally proliferating plasma cells secrete large amounts of mutated antibody light chains (LCs) that eventually form fibrils. The fibrils are deposited in various organs, most often in the heart and kidney, and impair their function. The prognosis for patients diagnosed with AL is generally poor. The disease is set apart from other amyloidoses by the huge number of patient-specific mutations in the disease-causing and fibril-forming protein. The molecular mechanisms that drive the aggregation of mutated LCs into fibrils have been enigmatic, which hindered the development of efficient diagnostics and therapies. In this review, we summarize our current knowledge on AL amyloidosis and discuss open issues.
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Affiliation(s)
- Ramona M Absmeier
- Center for Functional Protein Assemblies and Department of Chemistry, Technische Universität München, Garching, Germany
| | - Georg J Rottenaicher
- Center for Functional Protein Assemblies and Department of Chemistry, Technische Universität München, Garching, Germany
| | - Hristo L Svilenov
- Center for Functional Protein Assemblies and Department of Chemistry, Technische Universität München, Garching, Germany
| | - Pamina Kazman
- Center for Functional Protein Assemblies and Department of Chemistry, Technische Universität München, Garching, Germany
| | - Johannes Buchner
- Center for Functional Protein Assemblies and Department of Chemistry, Technische Universität München, Garching, Germany
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11
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Diagnostic Challenges and Solutions in Systemic Amyloidosis. Int J Mol Sci 2023; 24:ijms24054655. [PMID: 36902083 PMCID: PMC10003318 DOI: 10.3390/ijms24054655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Revised: 02/10/2023] [Accepted: 02/25/2023] [Indexed: 03/04/2023] Open
Abstract
Amyloidosis refers to a clinically heterogeneous group of disorders characterized by the extracellular deposition of amyloid proteins in various tissues of the body. To date, 42 different amyloid proteins that originate from normal precursor proteins and are associated with distinct clinical forms of amyloidosis have been described. Identification of the amyloid type is essential in clinical practice, since prognosis and treatment regimens both vary according to the particular amyloid disease. However, typing of amyloid protein is often challenging, especially in the two most common forms of amyloidosis, i.e., the immunoglobulin light chain amyloidosis and transthyretin amyloidosis. Diagnostic methodology is based on tissue examinations as well as on noninvasive techniques including serological and imaging studies. Tissue examinations vary depending on the tissue preparation mode, i.e., whether it is fresh-frozen or fixed, and they can be carried out by ample methodologies including immunohistochemistry, immunofluorescence, immunoelectron microscopy, Western blotting, and proteomic analysis. In this review, we summarize current methodological approaches used for the diagnosis of amyloidosis and discusses their utility, advantages, and limitations. Special attention is paid to the simplicity of the procedures and their availability in clinical diagnostic laboratories. Finally, we describe new methods recently developed by our team to overcome limitations existing in the standard assays used in common practice.
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12
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Muschol M, Hoyer W. Amyloid oligomers as on-pathway precursors or off-pathway competitors of fibrils. Front Mol Biosci 2023; 10:1120416. [PMID: 36845541 PMCID: PMC9947291 DOI: 10.3389/fmolb.2023.1120416] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Accepted: 01/27/2023] [Indexed: 02/11/2023] Open
Abstract
Amyloid Diseases involve the growth of disease specific proteins into amyloid fibrils and their deposition in protein plaques. Amyloid fibril formation is typically preceded by oligomeric intermediates. Despite significant efforts, the specific role fibrils or oligomers play in the etiology of any given amyloid disease remains controversial. In neurodegenerative disease, though, amyloid oligomers are widely considered critical contributors to disease symptoms. Aside from oligomers as inevitable on-pathway precursors of fibril formation, there is significant evidence for off-pathway oligomer formation competing with fibril growth. The distinct mechanisms and pathways of oligomer formation directly affect our understanding under which conditions oligomers emerge in vivo, and whether their formation is directly coupled to, or distinct from, amyloid fibril formation. In this review, we will discuss the basic energy landscapes underlying the formation of on-pathway vs. off-pathway oligomers, their relation to the related amyloid aggregation kinetics, and their resulting implications for disease etiology. We will review evidence on how differences in the local environment of amyloid assembly can dramatically shift the relative preponderance of oligomers vs. fibrils. Finally, we will comment on gaps in our knowledge of oligomer assembly, of their structure, and on how to assess their relevance to disease etiology.
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Affiliation(s)
- Martin Muschol
- Department of Physics, University of South Florida, Tampa, FL, United States,*Correspondence: Martin Muschol, ; Wolfgang Hoyer,
| | - Wolfgang Hoyer
- Institut für Physikalische Biologie, Heinrich-Heine-Universität, Düsseldorf, Germany,Institute of Biological Information Processing (IBI-7) and JuStruct, Jülich Center for Structural Biology, Forschungszentrum Jülich, Jülich, Germany,*Correspondence: Martin Muschol, ; Wolfgang Hoyer,
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13
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Bhoite SS, Han Y, Ruotolo BT, Chapman MR. Mechanistic insights into accelerated α-synuclein aggregation mediated by human microbiome-associated functional amyloids. J Biol Chem 2022; 298:102088. [PMID: 35654142 PMCID: PMC9253359 DOI: 10.1016/j.jbc.2022.102088] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2022] [Revised: 05/23/2022] [Accepted: 05/24/2022] [Indexed: 01/31/2023] Open
Abstract
The gut microbiome has been shown to have key implications in the pathogenesis of Parkinson's disease (PD). The Escherichia coli functional amyloid CsgA is known to accelerate α-synuclein aggregation in vitro and induce PD symptoms in mice. However, the mechanism governing CsgA-mediated acceleration of α-synuclein aggregation is unclear. Here, we show that CsgA can form stable homodimeric species that correlate with faster α-synuclein amyloid aggregation. Furthermore, we identify and characterize new CsgA homologs encoded by bacteria present in the human microbiome. These CsgA homologs display diverse aggregation kinetics, and they differ in their ability to modulate α-synuclein aggregation. Remarkably, we demonstrate that slowing down CsgA aggregation leads to an increased acceleration of α-synuclein aggregation, suggesting that the intrinsic amyloidogenicity of gut bacterial CsgA homologs affects their ability to accelerate α-synuclein aggregation. Finally, we identify a complex between CsgA and α-synuclein that functions as a platform to accelerate α-synuclein aggregation. Taken together, our work reveals complex interplay between bacterial amyloids and α-synuclein that better informs our understanding of PD causation.
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Affiliation(s)
- Sujeet S Bhoite
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, Michigan, USA
| | - Yilin Han
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan, USA
| | - Brandon T Ruotolo
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan, USA.
| | - Matthew R Chapman
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, Michigan, USA.
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14
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Dissection of the amyloid formation pathway in AL amyloidosis. Nat Commun 2021; 12:6516. [PMID: 34764275 PMCID: PMC8585945 DOI: 10.1038/s41467-021-26845-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 10/25/2021] [Indexed: 11/18/2022] Open
Abstract
In antibody light chain (AL) amyloidosis, overproduced light chain (LC) fragments accumulate as fibrils in organs and tissues of patients. In vitro, AL fibril formation is a slow process, characterized by a pronounced lag phase. The events occurring during this lag phase are largely unknown. We have dissected the lag phase of a patient-derived LC truncation and identified structural transitions that precede fibril formation. The process starts with partial unfolding of the VL domain and the formation of small amounts of dimers. This is a prerequisite for the formation of an ensemble of oligomers, which are the precursors of fibrils. During oligomerization, the hydrophobic core of the LC domain rearranges which leads to changes in solvent accessibility and rigidity. Structural transitions from an anti-parallel to a parallel β-sheet secondary structure occur in the oligomers prior to amyloid formation. Together, our results reveal a rate-limiting multi-step mechanism of structural transitions prior to fibril formation in AL amyloidosis, which offers, in the long run, opportunities for therapeutic intervention. AL amyloidosis is caused by the accumulation of overproduced light chain (LC) fragments as fibrils in patient organs and it is the most prevalent systemic amyloidosis. Here, the authors combine biochemical and biophysical experiments to characterise the lag phase of a patient-derived truncated LC and they identify structural transitions that precede fibril formation.
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15
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Understanding Mesangial Pathobiology in AL-Amyloidosis and Monoclonal Ig Light Chain Deposition Disease. Kidney Int Rep 2020; 5:1870-1893. [PMID: 33163710 PMCID: PMC7609979 DOI: 10.1016/j.ekir.2020.07.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 07/06/2020] [Accepted: 07/14/2020] [Indexed: 02/07/2023] Open
Abstract
Patients with plasma cell dyscrasias produce free abnormal monoclonal Ig light chains that circulate in the blood stream. Some of them, termed glomerulopathic light chains, interact with the mesangial cells and trigger, in a manner dependent of their structural and physicochemical properties, a sequence of pathological events that results in either light chain–derived (AL) amyloidosis (AL-Am) or light chain deposition disease (LCDD). The mesangial cells play a key role in the pathogenesis of both diseases. The interaction with the pathogenic light chain elicits specific cellular processes, which include apoptosis, phenotype transformation, and secretion of extracellular matrix components and metalloproteinases. Monoclonal light chains associated with AL-Am but not those producing LCDD are avidly endocytosed by mesangial cells and delivered to the mature lysosomal compartment where amyloid fibrils are formed. Light chains from patients with LCDD exert their pathogenic signaling effect at the cell surface of mesangial cells. These events are generic mesangial responses to a variety of adverse stimuli, and they are similar to those characterizing other more frequent glomerulopathies responsible for many cases of end-stage renal disease. The pathophysiologic events that have been elucidated allow to propose future therapeutic approaches aimed at preventing, stopping, ameliorating, or reversing the adverse effects resulting from the interactions between glomerulopathic light chains and mesangium.
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16
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Kumar AP, Lee S, Lukman S. Computational and Experimental Approaches to Design Inhibitors of Amylin Aggregation. Curr Drug Targets 2019; 20:1680-1694. [DOI: 10.2174/1389450120666190719164316] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 07/04/2019] [Accepted: 07/05/2019] [Indexed: 01/21/2023]
Abstract
Amylin is a neuroendocrine peptide hormone secreted by pancreatic ß-cells; however,
amylin is toxic to ß-cells when it is aggregated in type 2 diabetes mellitus (T2DM). It is important to
understand amylin’s structures and aggregation mechanism for the discovery and design of effective
drugs to inhibit amylin aggregation. In this review, we investigated experimental and computational
studies on amylin structures and inhibitors. Our review provides some novel insights into amylin, particularly
for the design of its aggregation inhibitors to treat T2DM. We detailed the potential inhibitors
that have been studied hitherto and highlighted the neglected need to consider different amylin attributes
that depend on the presence/absence of physiologically relevant conditions, such as membranes.
These conditions and the experimental methods can greatly influence the results of studies on amylininhibitor
complexes. Text-mining over 3,000 amylin-related PubMed abstracts suggests the combined
therapeutic potential of amylin with leptin and glucagon-like peptide-1, which are two key hormones
in obesity. The results also suggest that targeting amylin aggregation can contribute to therapeutic efforts
for Alzheimer’s disease (AD). Therefore, we have also reviewed the role of amylin in other conditions
including obesity and AD. Finally, we provided insights for designing inhibitors of different
types (small molecules, proteins, peptides/mimetics, metal ions) to inhibit amylin aggregation.
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Affiliation(s)
- Ammu Prasanna Kumar
- Department of Chemistry, College of Arts and Sciences, Khalifa University, Abu Dhabi, United Arab Emirates
| | - Sungmun Lee
- Department of Biomedical Engineering and Healthcare Engineering Innovation Center, College of Engineering, Khalifa University, Abu Dhabi, United Arab Emirates
| | - Suryani Lukman
- Department of Chemistry, College of Arts and Sciences, Khalifa University, Abu Dhabi, United Arab Emirates
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17
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Achieving cytochrome c fibril/aggregate control towards micro-platelets and micro-fibers by tuning pH and protein concentration: A combined morphological and spectroscopic analysis. Int J Biol Macromol 2019; 138:106-115. [DOI: 10.1016/j.ijbiomac.2019.07.060] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Revised: 07/05/2019] [Accepted: 07/07/2019] [Indexed: 11/20/2022]
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18
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Sasahara K, Yamaguchi K, So M, Goto Y. Polyphosphates diminish solubility of a globular protein and thereby promote amyloid aggregation. J Biol Chem 2019; 294:15318-15329. [PMID: 31439662 DOI: 10.1074/jbc.ra119.008662] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Revised: 08/21/2019] [Indexed: 01/08/2023] Open
Abstract
Structural changes of globular proteins and their resultant amyloid aggregation have been associated with various human diseases, such as lysozyme amyloidosis and light-chain amyloidosis. Because many globular proteins can convert into amyloid fibrils in vitro, the mechanisms of amyloid fibril formation have been studied in various experimental systems, but several questions remain unresolved. Here, using several approaches, such as turbidimetry, fluorescence and CD spectroscopy, EM, and isothermal titration calorimetry, we examined the binding of polyphosphates to hen egg-white lysozyme under acidic conditions and observed polyphosphate-induced structural changes of the protein promoting its aggregation. Our data indicate that negatively charged polyphosphates bind to protein molecules with a net positive charge. The polyphosphate-bound, structurally destabilized protein molecules then start assembling into insoluble amorphous aggregates once they pass the solubility limit. We further show that the polyphosphates decrease the solubility limit of the protein and near this limit, the protein molecules are in a labile state and highly prone to converting into amyloid fibrils. Our results explain how polyphosphates affect amorphous aggregation of proteins, how amyloid formation is induced in the presence of polyphosphates, and how polyphosphate chain length is an important factor in amyloid formation.
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Affiliation(s)
- Kenji Sasahara
- Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Keiichi Yamaguchi
- Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Masatomo So
- Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Yuji Goto
- Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565-0871, Japan
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19
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Misra P, Blancas-Mejia LM, Ramirez-Alvarado M. Mechanistic Insights into the Early Events in the Aggregation of Immunoglobulin Light Chains. Biochemistry 2019; 58:3155-3168. [PMID: 31287666 DOI: 10.1021/acs.biochem.9b00311] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Little is known about the mechanism of amyloid assembly in immunoglobulin light chain (AL) amyloidosis, in contrast to other amyloid diseases. Early events in the aggregation pathway are especially important, as these soluble species could be cytotoxic intermediates playing a critical role in the initiation of the amyloid assembly. In this work, we discuss the mechanism of the early events in in vitro fibril formation of immunoglobulin light chain AL-09 and AL-12 (involved in cardiac amyloidosis) and its germline (control) protein κI O18/O8. Previous work from our laboratory showed that AL-12 adopts a canonical dimer conformation (like the germline protein), whereas AL-09 presents an altered dimer interface as a result of somatic mutations. Both AL-12 and AL-09 aggregate with similar rates and significantly faster than the germline protein. AL-09 is the only protein in this study that forms stable oligomeric intermediates during the early stages of the aggregation reaction with some structural rearrangements that increase the thioflavin T fluorescence but maintain the same number of monomers in solution. The presence of the restorative mutation AL-09 H87Y changes the kinetics and the aggregation pathway compared to AL-09. The single restorative mutation AL-12 R65S slightly delayed the overall rate of aggregation as compared to AL-12. Collectively, our study provides a comprehensive analysis of species formed during amyloid nucleation in AL amyloidosis, shows a strong dependence between the altered dimer conformation and the formation of stable oligomeric intermediates, and sheds light on the structural features of amyloidogenic intermediates associated with cellular toxicity.
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20
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Perez C, Miti T, Hasecke F, Meisl G, Hoyer W, Muschol M, Ullah G. Mechanism of Fibril and Soluble Oligomer Formation in Amyloid Beta and Hen Egg White Lysozyme Proteins. J Phys Chem B 2019; 123:5678-5689. [PMID: 31246474 DOI: 10.1021/acs.jpcb.9b02338] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Assembly and deposition of insoluble amyloid fibrils with a distinctive cross-β-sheet structure is the molecular hallmark of amyloidogenic diseases affecting the central nervous system as well as non-neuropathic amyloidosis. Amyloidogenic proteins form aggregates via kinetic pathways dictated by initial solution conditions. Often, early stage, cytotoxic, small globular amyloid oligomers (gOs) and curvilinear fibrils (CFs) precede the formation of late-stage rigid fibrils (RFs). Growing experimental evidence suggests that soluble gOs are off-pathway aggregates that do not directly convert into the final stage RFs. Yet, the kinetics of RFs aggregation under conditions that either promote or suppress the growth of gOs remain incompletely understood. Here we present a self-assembly model for amyloid fibril formation in the presence and absence of early stage off-pathway aggregates, driven by our experimental results on hen egg white lysozyme (HewL) and beta amyloid (Aβ) aggregation. The model reproduces a range of experimental observations including the sharp boundary in the protein concentration above which the self-assembly of gOs occurs. This is possible when both primary and secondary RFs nucleation rates are allowed to have a nonlinear dependence on initial protein concentration, hinting toward more complex prenucleation and RFs assembly scenarios. Moreover, analysis of RFs lag period in the presence and absence of gOs indicates that these off-pathway aggregates have an inhibitory effect on RFs nucleation. Finally, we incorporate the effect of an Aβ binding protein on the aggregation process in the model that allows us to identify the most suitable solution conditions for suppressing gOs and RFs formation.
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Affiliation(s)
- Carlos Perez
- Department of Physics , University of South Florida , Tampa , Florida 33620 , United States
| | - Tatiana Miti
- Department of Physics , University of South Florida , Tampa , Florida 33620 , United States
| | - Filip Hasecke
- Institut für Physikalische Biologie , Heinrich-Heine-Universität , 40204 Düsseldorf , Germany
| | - Georg Meisl
- Department of Chemistry , University of Cambridge , Lensfield Road , Cambridge CB2 1EW , U.K
| | - Wolfgang Hoyer
- Department of Chemistry , University of Cambridge , Lensfield Road , Cambridge CB2 1EW , U.K.,Institute of Complex Systems (ICS-6), Structural Biochemistry , Research Centre Jülich , 52425 Jülich , Germany
| | - Martin Muschol
- Department of Physics , University of South Florida , Tampa , Florida 33620 , United States
| | - Ghanim Ullah
- Department of Physics , University of South Florida , Tampa , Florida 33620 , United States
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21
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Grazioli G, Yu Y, Unhelkar MH, Martin RW, Butts CT. Network-Based Classification and Modeling of Amyloid Fibrils. J Phys Chem B 2019; 123:5452-5462. [PMID: 31095387 DOI: 10.1021/acs.jpcb.9b03494] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Amyloid fibrils are locally ordered protein aggregates that self-assemble under a variety of physiological and in vitro conditions. Their formation is of fundamental interest as a physical chemistry problem and plays a central role in Alzheimer's disease, Type II diabetes, and other human diseases. As the number of known amyloid fibril structures has grown, the need has arisen for a nomenclature for describing and classifying fibril types, as well as a theoretical description of the physics that gives rise to the self-assembly of these structures. Here, we introduce a systematic nomenclature and coarse-graining methodology for describing the topology of fibrils and other protein aggregates, along with a computational methodology for simulating protein aggregation. Both have mathematical underpinnings in graph theory and statistical mechanics and are consistent with available experimental data on the fibril structure and aggregation kinetics. Our graph representation of the fibril topology enables us to define a network Hamiltonian based on connectivity patterns among monomers rather than detailed intermolecular interactions, greatly speeding up the simulation of large ensembles. Our simulation strategy is capable of recapitulating the formation of all currently known amyloid fibril topologies found in the Protein Data Bank, as well as the formation kinetics of fibrils and oligomers.
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22
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Furkan M, Siddiqi MK, Zakariya SM, Khan FI, Hassan MI, Khan RH. An In Vitro elucidation of the antiaggregatory potential of Diosminover thermally induced unfolding of hen egg white lysozyme; A preventive quest for lysozyme amyloidosis. Int J Biol Macromol 2019; 129:1015-1023. [DOI: 10.1016/j.ijbiomac.2019.02.107] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Revised: 02/18/2019] [Accepted: 02/18/2019] [Indexed: 01/24/2023]
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23
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Hasecke F, Miti T, Perez C, Barton J, Schölzel D, Gremer L, Grüning CSR, Matthews G, Meisl G, Knowles TPJ, Willbold D, Neudecker P, Heise H, Ullah G, Hoyer W, Muschol M. Origin of metastable oligomers and their effects on amyloid fibril self-assembly. Chem Sci 2018; 9:5937-5948. [PMID: 30079208 PMCID: PMC6050532 DOI: 10.1039/c8sc01479e] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2018] [Accepted: 06/12/2018] [Indexed: 01/05/2023] Open
Abstract
Assembly of rigid amyloid fibrils with their characteristic cross-β sheet structure is a molecular signature of numerous neurodegenerative and non-neuropathic disorders. Frequently large populations of small globular amyloid oligomers (gOs) and curvilinear fibrils (CFs) precede the formation of late-stage rigid fibrils (RFs), and have been implicated in amyloid toxicity. Yet our understanding of the origin of these metastable oligomers, their role as on-pathway precursors or off-pathway competitors, and their effects on the self-assembly of amyloid fibrils remains incomplete. Using two unrelated amyloid proteins, amyloid-β and lysozyme, we find that gO/CF formation, analogous to micelle formation by surfactants, is delineated by a "critical oligomer concentration" (COC). Below this COC, fibril assembly replicates the sigmoidal kinetics of nucleated polymerization. Upon crossing the COC, assembly kinetics becomes biphasic with gO/CF formation responsible for the lag-free initial phase, followed by a second upswing dominated by RF nucleation and growth. RF lag periods below the COC, as expected, decrease as a power law in monomer concentration. Surprisingly, the build-up of gO/CFs above the COC causes a progressive increase in RF lag periods. Our results suggest that metastable gO/CFs are off-pathway from RF formation, confined by a condition-dependent COC that is distinct from RF solubility, underlie a transition from sigmoidal to biphasic assembly kinetics and, most importantly, not only compete with RFs for the shared monomeric growth substrate but actively inhibit their nucleation and growth.
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Affiliation(s)
- Filip Hasecke
- Institut für Physikalische Biologie , Heinrich-Heine-Universität , 40204 Düsseldorf , Germany .
| | - Tatiana Miti
- Department of Physics , University of South Florida , Tampa , FL 33620 , USA .
| | - Carlos Perez
- Department of Physics , University of South Florida , Tampa , FL 33620 , USA .
| | - Jeremy Barton
- Department of Physics , University of South Florida , Tampa , FL 33620 , USA .
| | - Daniel Schölzel
- Institut für Physikalische Biologie , Heinrich-Heine-Universität , 40204 Düsseldorf , Germany .
- Institute of Complex Systems (ICS-6) , Structural Biochemistry , Research Centre Jülich , Germany
| | - Lothar Gremer
- Institut für Physikalische Biologie , Heinrich-Heine-Universität , 40204 Düsseldorf , Germany .
- Institute of Complex Systems (ICS-6) , Structural Biochemistry , Research Centre Jülich , Germany
| | - Clara S R Grüning
- Institut für Physikalische Biologie , Heinrich-Heine-Universität , 40204 Düsseldorf , Germany .
| | - Garrett Matthews
- Department of Physics , University of South Florida , Tampa , FL 33620 , USA .
| | - Georg Meisl
- Department of Chemistry , University of Cambridge , Lensfield Road , Cambridge CB2 1EW , UK
| | - Tuomas P J Knowles
- Department of Chemistry , University of Cambridge , Lensfield Road , Cambridge CB2 1EW , UK
| | - Dieter Willbold
- Institut für Physikalische Biologie , Heinrich-Heine-Universität , 40204 Düsseldorf , Germany .
- Institute of Complex Systems (ICS-6) , Structural Biochemistry , Research Centre Jülich , Germany
| | - Philipp Neudecker
- Institut für Physikalische Biologie , Heinrich-Heine-Universität , 40204 Düsseldorf , Germany .
- Institute of Complex Systems (ICS-6) , Structural Biochemistry , Research Centre Jülich , Germany
| | - Henrike Heise
- Institut für Physikalische Biologie , Heinrich-Heine-Universität , 40204 Düsseldorf , Germany .
- Institute of Complex Systems (ICS-6) , Structural Biochemistry , Research Centre Jülich , Germany
| | - Ghanim Ullah
- Department of Physics , University of South Florida , Tampa , FL 33620 , USA .
| | - Wolfgang Hoyer
- Institut für Physikalische Biologie , Heinrich-Heine-Universität , 40204 Düsseldorf , Germany .
- Institute of Complex Systems (ICS-6) , Structural Biochemistry , Research Centre Jülich , Germany
| | - Martin Muschol
- Department of Physics , University of South Florida , Tampa , FL 33620 , USA .
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24
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Velázquez-López I, Valdés-García G, Romero Romero S, Maya Martínez R, Leal-Cervantes AI, Costas M, Sánchez-López R, Amero C, Pastor N, Fernández Velasco DA. Localized conformational changes trigger the pH-induced fibrillogenesis of an amyloidogenic λ light chain protein. Biochim Biophys Acta Gen Subj 2018; 1862:1656-1666. [PMID: 29669263 DOI: 10.1016/j.bbagen.2018.04.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Revised: 02/04/2018] [Accepted: 04/13/2018] [Indexed: 01/04/2023]
Abstract
Solvent conditions modulate the expression of the amyloidogenic potential of proteins. In this work the effect of pH on the fibrillogenic behavior and the conformational properties of 6aJL2, a model protein of the highly amyloidogenic variable light chain λ6a gene segment, was examined. Ordered aggregates showing the ultrastructural and spectroscopic properties observed in amyloid fibrils were formed in the 2.0-8.0 pH range. At pH <3.0 a drastic decrease in lag time and an increase in fibril formation rate were found. In the 4.0-8.0 pH range there was no spectroscopic evidence for significant conformational changes in the native state. Likewise, heat capacity measurements showed no evidence for residual structure in the unfolded state. However, at pH <3.0 stability is severely decreased and the protein suffers conformational changes as detected by circular dichroism, tryptophan and ANS fluorescence, as well as by NMR spectroscopy. Molecular dynamics simulations indicate that acid-induced conformational changes involve the exposure of the loop connecting strands E and F. These results are compatible with pH-induced changes in the NMR spectra. Overall, the results indicate that the mechanism involved in the acid-induced increase in the fibrillogenic potential of 6aJL2 is profoundly different to that observed in κ light chains, and is promoted by localized conformational changes in a region of the protein that was previously not known to be involved in acid-induced light chain fibril formation. The identification of this region opens the potential for the design of specific inhibitors.
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Affiliation(s)
- Isabel Velázquez-López
- Laboratorio de Fisicoquímica e Ingeniería de Proteínas, Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, México
| | - Gilberto Valdés-García
- Centro de Investigación en Dinámica Celular, IICBA, Universidad Autónoma del Estado de Morelos, México
| | - Sergio Romero Romero
- Laboratorio de Fisicoquímica e Ingeniería de Proteínas, Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, México
| | - Roberto Maya Martínez
- Centro de Investigaciones Químicas, IICBA, Universidad Autónoma del Estado de Morelos, México
| | - Ana I Leal-Cervantes
- Laboratorio de Fisicoquímica e Ingeniería de Proteínas, Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, México
| | - Miguel Costas
- Laboratorio de Biofisicoquímica, Departamento de Fisicoquímica, Facultad de Química, Universidad Nacional Autónoma de México, México
| | | | - Carlos Amero
- Centro de Investigaciones Químicas, IICBA, Universidad Autónoma del Estado de Morelos, México
| | - Nina Pastor
- Centro de Investigación en Dinámica Celular, IICBA, Universidad Autónoma del Estado de Morelos, México.
| | - D Alejandro Fernández Velasco
- Laboratorio de Fisicoquímica e Ingeniería de Proteínas, Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, México.
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25
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Effect of amino acid mutations on the conformational dynamics of amyloidogenic immunoglobulin light-chains: A combined NMR and in silico study. Sci Rep 2017; 7:10339. [PMID: 28871194 PMCID: PMC5583243 DOI: 10.1038/s41598-017-10906-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Accepted: 08/16/2017] [Indexed: 12/19/2022] Open
Abstract
The conformational dynamics of a pathogenic κ4 human immunoglobulin light-chain variable domain, SMA, associated with AL amyloidosis, were investigated by 15N relaxation dispersion NMR spectroscopy. Compared to a homologous light-chain, LEN, which differs from SMA at eight positions but is non-amyloidogenic in vivo, we find that multiple residues in SMA clustered around the N-terminus and CDR loops experience considerable conformational exchange broadening caused by millisecond timescale protein motions, consistent with a destabilized dimer interface. To evaluate the contribution of each amino acid substitution to shaping the dynamic conformational landscape of SMA, NMR studies were performed for each SMA-like point mutant of LEN followed by in silico analysis for a subset of these proteins. These studies show that a combination of only three mutations located within or directly adjacent to CDR3 loop at the dimer interface, which remarkably include both destabilizing (Q89H and Y96Q) and stabilizing (T94H) mutations, largely accounts for the differences in conformational flexibility between LEN and SMA. Collectively, our studies indicate that a correct combination of stabilizing and destabilizing mutations is key for immunoglobulin light-chains populating unfolded intermediates that result in amyloid formation, and underscore the complex nature of correlations between light-chain conformational flexibility, thermodynamic stability and amyloidogenicity.
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26
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Secondary structural alterations in glucoamylase as an influence of protein aggregation. Int J Biol Macromol 2017; 98:459-468. [DOI: 10.1016/j.ijbiomac.2017.01.086] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Revised: 01/15/2017] [Accepted: 01/18/2017] [Indexed: 11/21/2022]
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27
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Crespo R, Villar-Alvarez E, Taboada P, Rocha FA, Damas AM, Martins PM. Insoluble Off-Pathway Aggregates as Crowding Agents during Amyloid Fibril Formation. J Phys Chem B 2017; 121:2288-2298. [DOI: 10.1021/acs.jpcb.7b01120] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Affiliation(s)
- Rosa Crespo
- LEPABE,
Laboratório de Engenharia de Processos, Ambiente, Biotecnologia
e Energia, Departamento de Engenharia Química, Faculdade de Engenharia da Universidade do Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
| | - Eva Villar-Alvarez
- Área
de Física de la Materia Condensada, Facultad de Física, Universidad de Santiago de Compostela, Santiago de Compostela 15782, Spain
| | - Pablo Taboada
- Área
de Física de la Materia Condensada, Facultad de Física, Universidad de Santiago de Compostela, Santiago de Compostela 15782, Spain
| | - Fernando A. Rocha
- LEPABE,
Laboratório de Engenharia de Processos, Ambiente, Biotecnologia
e Energia, Departamento de Engenharia Química, Faculdade de Engenharia da Universidade do Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
| | - Ana M. Damas
- ICBAS
− Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Porto 4050-313, Portugal
| | - Pedro M. Martins
- LEPABE,
Laboratório de Engenharia de Processos, Ambiente, Biotecnologia
e Energia, Departamento de Engenharia Química, Faculdade de Engenharia da Universidade do Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
- ICBAS
− Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Porto 4050-313, Portugal
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28
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Zottig X, Laporte Wolwertz M, Golizeh M, Ohlund L, Sleno L, Bourgault S. Effects of oxidative post-translational modifications on structural stability and self-assembly of λ6 immunoglobulin light chain. Biophys Chem 2016; 219:59-68. [DOI: 10.1016/j.bpc.2016.10.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Revised: 09/28/2016] [Accepted: 10/08/2016] [Indexed: 11/25/2022]
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29
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Furkan M, Fazili NA, Afsar M, Naeem A. Analysing Cytochrome c Aggregation and Fibrillation upon Interaction with Acetonitrile: an in Vitro Study. J Fluoresc 2016; 26:1959-1966. [PMID: 27550168 DOI: 10.1007/s10895-016-1889-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2016] [Accepted: 07/19/2016] [Indexed: 01/27/2023]
Abstract
The propensity of native state to form aggregated and fibrillar assemblies is a hallmark of amyloidosis. Our study was focused at analyzing the aggregation and fibrillation tendency of cytochrome c in presence of an organic solvent i.e. acetonitrile. In vitro analysis revealed that the interaction of cytochrome c with acetonitrile facilitated the oligomerization of cytochrome c via the passage through an intermediate state which was obtained at 20 % v/v concentration of acetonitrile featured by a sharp hike in the ANS fluorescence intensity with a blue shift of 20 nm compared to the native state. Oligomers and fibrils were formed at 40 and 50 % v/v concentration respectively as indicated by a significant hike in the ThT fluorescence intensity, red shift of 55 nm in congo red binding assay and an increase in absorbance at 350 nm. They possess β-sheet structure as evident from appearance of peak at 217 nm. Finally, authenticity of oligomeric and fibrillar species was confirmed by TEM imaging which revealed bead like aggregates and a meshwork of thread like fibrils respectively. It could be suggested that the fibrillation of bovine cytchrome c could serve as a model protein to unravel the general aggregation and fibrillation pattern of heme proteins. Graphical abstract ᅟ.
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Affiliation(s)
- Mohammad Furkan
- Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, UP, 202 002, India
| | - Naveed Ahmad Fazili
- Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, UP, 202 002, India
| | - Mohammad Afsar
- Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, UP, 202 002, India
| | - Aabgeena Naeem
- Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, UP, 202 002, India.
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30
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Fazili NA, Naeem A. Exploring the Transition of Human α-Synuclein from Native to the Fibrillar State: Insights into the Pathogenesis of Parkinson's Disease. J Fluoresc 2016; 26:1659-69. [PMID: 27365127 DOI: 10.1007/s10895-016-1856-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Accepted: 06/14/2016] [Indexed: 12/11/2022]
Abstract
The etiology of Parkinson's disease involves the interplay between the environmental and genetic factors. Here in this study human α-synuclein upon exposure to 100 μM pendimethalin for 12 h in vitro passes through a partially folded state which proceeds to the aggregated state and terminally ends in the fibrillar phase. Variations in the ANS fluorescence intensities led to the detection of intermediate and aggregated states at 6 and 10 h respectively. Far-UV CD analysis depicted significant α-helical content for intermediate state at 6 h in presence of 100 μM pendimethalin. Further increasing the incubation time to 12 h resulted in a predominant β-sheet content which was confirmed to be fibrillar by TEM. Turbidity, Rayleigh scattering analysis, Congo red assay and ThT measurements supported the TEM data i.e. the formation of fibrillar structure of human α-synuclein upon 12 h incubation. Thus, our observation could suggest a possible underlying molecular basis for Parkinson's disease. Graphical Abstract Schematic elucidation of the factors involved in the fibrillation of α-Synuclein during Parkinson's pathogenesis.
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Affiliation(s)
- Naveed Ahmad Fazili
- Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, 202 002, India
| | - Aabgeena Naeem
- Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, 202 002, India.
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31
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Probing the role of λ6 immunoglobulin light chain dimerization in amyloid formation. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2016; 1864:409-18. [PMID: 26802902 DOI: 10.1016/j.bbapap.2016.01.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2015] [Revised: 01/04/2016] [Accepted: 01/05/2016] [Indexed: 01/22/2023]
Abstract
Light chain amyloidosis (AL) is a lethal disease associated with the deposition of misfolded immunoglobulin light chains (LC) as amyloid fibrils in the extracellular space of vital organs. The exact mechanisms of LC self-assembly and the molecular basis leading to cellular and organ failure still remain poorly understood. In this study, we investigated the relationship between the quaternary structure, the stability and the amyloidogenecity of LC variable domain (VL) from the λ6 germline. We observed that the amyloidogenic λ6 Wil and its non-amyloidogenic counterpart Jto dimerize in a concentration-dependent manner and that the dimer affinity is considerably decreased in the presence of a high ionic strength. Our results showed that the dimeric state delays the structural conversion associated with amyloid formation and that the monomer is critical to initiate amyloidogenesis. Thermal and chemical unfolding studies revealed that the dimeric state of VL λ6 has an equivalent stability to the monomer. This indicates that the protective effect of dimerization is not related to thermodynamic stability but, most likely, resides in specific structural features. The toxicity of monomeric Jto and Wil as well as fibrillar aggregates was evaluated on cardiomyoblasts and ThT-negative proteospecies reduced cellular viability when employed at high concentration. This study provides novel insights into the complex process of LC amyloidogenesis and suggests that dimer stabilization constitutes a promising strategy to prevent self-assembly and amyloid deposition.
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32
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Mothi N, Muthu SA, Kale A, Ahmad B. Curcumin promotes fibril formation in F isomer of human serum albumin via amorphous aggregation. Biophys Chem 2015; 207:30-9. [PMID: 26298484 DOI: 10.1016/j.bpc.2015.08.002] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Revised: 07/22/2015] [Accepted: 08/08/2015] [Indexed: 12/16/2022]
Abstract
We here describe the amyloid fibrils promoting behavior of curcumin, which ability to inhibit amyloid fibrillization of several globular proteins is well documented. Transmission electron microscopy (TEM), 90° light scattering (RLS), thioflavine T (ThT) and Congo red (CR) binding studies demonstrated that both F (pH3.4) and E (pH1.8) isomers of human serum albumin (HSA) in the absence and presence of curcumin initially converted into amorphous aggregates. Interestingly, only the sample containing F isomer preincubated with curcumin formed fibrils on incubation for longer period. We also found that curcumin strongly bind to the F isomer, alter its secondary, tertiary structures and thermal stability. We conclude that the conversion of intermediate states into amorphous aggregate to fibrils is dictated by its conformation. This study provides unique insights into ligand-controlled HSA aggregation pathway and should provide a useful model system to study both amorphous and the fibrillar aggregation of multidomain proteins.
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Affiliation(s)
- Nivin Mothi
- Biophysical Chemistry & Structural Biology Laboratory, UM-DAE Centre for Excellence in Basic Sciences, University of Mumbai, Vidhyanagari Campus, Mumbai-400098, India
| | - Shivani A Muthu
- Biophysical Chemistry & Structural Biology Laboratory, UM-DAE Centre for Excellence in Basic Sciences, University of Mumbai, Vidhyanagari Campus, Mumbai-400098, India
| | - Avinash Kale
- Biophysical Chemistry & Structural Biology Laboratory, UM-DAE Centre for Excellence in Basic Sciences, University of Mumbai, Vidhyanagari Campus, Mumbai-400098, India
| | - Basir Ahmad
- Biophysical Chemistry & Structural Biology Laboratory, UM-DAE Centre for Excellence in Basic Sciences, University of Mumbai, Vidhyanagari Campus, Mumbai-400098, India.
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33
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Adachi M, So M, Sakurai K, Kardos J, Goto Y. Supersaturation-limited and Unlimited Phase Transitions Compete to Produce the Pathway Complexity in Amyloid Fibrillation. J Biol Chem 2015; 290:18134-18145. [PMID: 26063798 DOI: 10.1074/jbc.m115.648139] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2015] [Indexed: 01/16/2023] Open
Abstract
Although amyloid fibrils and amorphous aggregates are two types of aggregates formed by denatured proteins, their relationship currently remains unclear. We used β2-microglobulin (β2m), a protein responsible for dialysis-related amyloidosis, to clarify the mechanism by which proteins form either amyloid fibrils or amorphous aggregates. When ultrasonication was used to accelerate the spontaneous fibrillation of β2m at pH 2.0, the effects observed depended on ultrasonic power; although stronger ultrasonic power effectively accelerated fibrillation, excessively strong ultrasonic power decreased the amount of fibrils formed, as monitored by thioflavin T fluorescence. An analysis of the products formed indicated that excessively strong ultrasonic power generated fibrillar aggregates that retained β-structures but without high efficiency as seeds. On the other hand, when the spontaneous fibrillation of β2m was induced at higher concentrations of NaCl at pH 2.0 with stirring, amorphous aggregates became more dominant than amyloid fibrils. These apparent complexities in fibrillation were explained comprehensively by a competitive mechanism in which supersaturation-limited reactions competed with supersaturation-unlimited reactions. We link the kinetics of protein aggregation and a conformational phase diagram, in which supersaturation played important roles.
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Affiliation(s)
- Masayuki Adachi
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan
| | - Masatomo So
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan
| | - Kazumasa Sakurai
- High Pressure Protein Research Center, Institute for Advanced Technology, Kinki University, 930 Nishimitani, Kinokawa, Wakayama 649-6493, Japan
| | - József Kardos
- Department of Biochemistry and MTA-ELTE NAP B Neuroimmunology Research Group, Eötvös Loránd University, Pázmány sétány 1/C, Budapest, 1117, Hungary
| | - Yuji Goto
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan.
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34
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Anti-fibrillation potency of caffeic acid against an antidepressant induced fibrillogenesis of human α-synuclein: Implications for Parkinson's disease. Biochimie 2015; 108:178-85. [DOI: 10.1016/j.biochi.2014.11.011] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2014] [Accepted: 11/13/2014] [Indexed: 11/19/2022]
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35
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Blancas-Mejía LM, Hammernik J, Marin-Argany M, Ramirez-Alvarado M. Differential effects on light chain amyloid formation depend on mutations and type of glycosaminoglycans. J Biol Chem 2014; 290:4953-4965. [PMID: 25538238 DOI: 10.1074/jbc.m114.615401] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Amyloid light chain (AL) amyloidosis is a protein misfolding disease where immunoglobulin light chains sample partially folded states that lead to misfolding and amyloid formation, resulting in organ dysfunction and death. In vivo, amyloid deposits are found in the extracellular space and involve a variety of accessory molecules, such as glycosaminoglycans, one of the main components of the extracellular matrix. Glycosaminoglycans are a group of negatively charged heteropolysaccharides composed of repeating disaccharide units. In this study, we investigated the effect of glycosaminoglycans on the kinetics of amyloid fibril formation of three AL cardiac amyloidosis light chains. These proteins have similar thermodynamic stability but exhibit different kinetics of fibril formation. We also studied single restorative and reciprocal mutants and wild type germ line control protein. We found that the type of glycosaminoglycan has a different effect on the kinetics of fibril formation, and this effect seems to be associated with the natural propensity of each AL protein to form fibrils. Heparan sulfate accelerated AL-12, AL-09, κI Y87H, and AL-103 H92D fibril formation; delayed fibril formation for AL-103; and did not promote any fibril formation for AL-12 R65S, AL-103 delP95aIns, or κI O18/O8. Chondroitin sulfate A, on the other hand, showed a strong fibril formation inhibition for all proteins. We propose that heparan sulfate facilitates the formation of transient amyloidogenic conformations of AL light chains, thereby promoting amyloid formation, whereas chondroitin sulfate A kinetically traps partially unfolded intermediates, and further fibril elongation into fibrils is inhibited, resulting in formation/accumulation of oligomeric/protofibrillar aggregates.
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Affiliation(s)
| | - Jared Hammernik
- School of Molecular and Cellular Biology, University of Illinois, Urbana, Illinois 61801
| | | | - Marina Ramirez-Alvarado
- Departments of Biochemistry and Molecular Biology and; Immunology, Mayo Clinic, Rochester, Minnesota 55905 and.
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36
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Paslawski W, Andreasen M, Nielsen SB, Lorenzen N, Thomsen K, Kaspersen JD, Pedersen JS, Otzen DE. High stability and cooperative unfolding of α-synuclein oligomers. Biochemistry 2014; 53:6252-63. [PMID: 25216651 DOI: 10.1021/bi5007833] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Many neurodegenerative diseases are linked with formation of amyloid aggregates. It is increasingly accepted that not the fibrils but rather oligomeric species are responsible for degeneration of neuronal cells. Strong evidence suggests that in Parkinson's disease (PD), cytotoxic α-synuclein (αSN) oligomers are key to pathogenicity. Nevertheless, insight into the oligomers' molecular properties remains scarce. Here we show that αSN oligomers, despite a large amount of disordered structure, are remarkably stable against extreme pH, temperature, and even molar amounts of chemical denaturants, though they undergo cooperative unfolding at higher denaturant concentrations. Mutants found in familial PD lead to slightly larger oligomers whose stabilities are very similar to that of wild-type αSN. Isolated oligomers do not revert to monomers but predominantly form larger aggregates consisting of stacked oligomers, suggesting that they are off-pathway relative to the process of fibril formation. We also demonstrate that 4-(dicyanovinyl)julolidine (DCVJ) can be used as a specific probe for detection of αSN oligomers. The high stability of the αSN oligomer indicates that therapeutic strategies should aim to prevent the formation of or passivate rather than dissociate this cytotoxic species.
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Affiliation(s)
- Wojciech Paslawski
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University , Gustav Wieds Vej 14, DK - 8000 Aarhus C, Denmark
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37
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Sulatskaya AI, Volova EA, Komissarchik YY, Snigirevskaya ES, Maskevich AA, Drobchenko EA, Kuznetsova IM, Turoverov KK. Investigation of the kinetics of insulin amyloid fibrils formation. ACTA ACUST UNITED AC 2014. [DOI: 10.1134/s1990519x14020114] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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38
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Induction of amyloidogenicity in wild type HEWL by a dialdehyde: Analysis involving multi dimensional approach. Int J Biol Macromol 2014; 64:36-44. [DOI: 10.1016/j.ijbiomac.2013.11.010] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2013] [Revised: 11/17/2013] [Accepted: 11/18/2013] [Indexed: 11/23/2022]
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39
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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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40
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Rawat A, Nagaraj R. Covalently attached fatty acyl chains alter the aggregation behavior of an amyloidogenic peptide derived from human β(2)-microglobulin. J Pept Sci 2013; 19:770-83. [PMID: 24243599 DOI: 10.1002/psc.2575] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2013] [Revised: 09/17/2013] [Accepted: 09/23/2013] [Indexed: 12/14/2022]
Abstract
Aggregation of a polypeptide chain into highly ordered amyloid aggregates is a complex process. Various factors, both extrinsic and intrinsic to the polypeptide chain, have been shown to perturb this process, leading to a drastic change in the amyloidogenic behavior, which is reflected in the polymorphism of amyloid aggregates at various levels of self-assembly. In this paper, we have investigated the ability of covalently linked long-chain fatty acids in modulating the self-assembly of an aromatic amino acid-rich highly amyloidogenic sequence derived from the amino acid region 59-71 of human β2-microglobulin by thioflavin T (ThT) fluorescence microscopy, circular dichroism, and fluorescence spectroscopy. Our results indicate that under identical conditions of dissolution and concentration, each peptide enhances the fluorescence of ThT. However, the aggregates are morphologically distinct. For the same peptide, the aggregate morphologies are dependent on peptide concentration. Further, an optimum concentration, which varies with solution ionic strength, is required for the formation of fibrillar aggregates. We show that covalent modification of this amyloidogenic sequence, with long-chain fatty acids, affects the way the higher order amyloid structures assemble from the cross-β units, in fatty acyl chain-dependent and position-dependent manner. Our data indicate that noncovalent interactions leading to amyloid fibril formation can be modulated by the hydrophobicity of covalently attached long-chain fatty acids resulting in self-assembly of the peptide chain to form nonfibrillar aggregates.
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Affiliation(s)
- Anoop Rawat
- CSIR - Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad, 500 007, India
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41
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Blancas-Mejía LM, Tischer A, Thompson JR, Tai J, Wang L, Auton M, Ramirez-Alvarado M. Kinetic control in protein folding for light chain amyloidosis and the differential effects of somatic mutations. J Mol Biol 2013; 426:347-61. [PMID: 24157440 DOI: 10.1016/j.jmb.2013.10.016] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2013] [Revised: 08/30/2013] [Accepted: 10/07/2013] [Indexed: 10/26/2022]
Abstract
Light chain amyloidosis is a devastating disease where immunoglobulin light chains form amyloid fibrils, resulting in organ dysfunction and death. Previous studies have shown a direct correlation between the protein thermodynamic stability and the propensity for amyloid formation for some proteins involved in light chain amyloidosis. Here we investigate the effect of somatic mutations on protein stability and in vitro fibril formation of single and double restorative mutants of the protein AL-103 compared to the wild-type germline control protein. A scan rate dependence and hysteresis in the thermal unfolding and refolding was observed for all proteins. This indicates that the unfolding/refolding reaction is kinetically determined with different kinetic constants for unfolding and refolding even though the process remains experimentally reversible. Our structural analysis of AL-103 and AL-103 delP95aIns suggests a kinetic coupling of the unfolding/refolding process with cis-trans prolyl isomerization. Our data reveal that the deletion of proline 95a (AL-103 delP95aIns), which removes the trans-cis di-proline motif present in the patient protein AL-103, results in a dramatic increment in the thermodynamic stability and a significant delay in fibril formation kinetics with respect to AL-103. Fibril formation is pH dependent; all proteins form fibrils at pH2; reactions become slower and more stochastic as the pH increases up to pH7. Based on these results, we propose that, in addition to thermodynamic stability, kinetic stability (possibly influenced by the presence of cis proline 95a) plays a major role in the AL-103 amyloid fibril formation process.
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Affiliation(s)
- Luis M Blancas-Mejía
- Department of Biochemistry and Molecular Biology, Mayo Clinic, 200 First Street Southwest, Rochester, MN 55905, USA
| | - Alexander Tischer
- Department of Biochemistry and Molecular Biology, Mayo Clinic, 200 First Street Southwest, Rochester, MN 55905, USA; Division of Hematology, Mayo Clinic, 200 First Street Southwest, Rochester, MN 55905, USA
| | - James R Thompson
- Department of Physiology and Biomedical Engineering, Mayo Clinic, 200 First Street Southwest, Rochester, MN 55905, USA
| | - Jonathan Tai
- Department of Chemistry, University of Illinois, Urbana, IL 61801, USA
| | - Lin Wang
- Department of Biochemistry and Molecular Biology, Mayo Clinic, 200 First Street Southwest, Rochester, MN 55905, USA
| | - Matthew Auton
- Department of Biochemistry and Molecular Biology, Mayo Clinic, 200 First Street Southwest, Rochester, MN 55905, USA; Division of Hematology, Mayo Clinic, 200 First Street Southwest, Rochester, MN 55905, USA
| | - Marina Ramirez-Alvarado
- Department of Biochemistry and Molecular Biology, Mayo Clinic, 200 First Street Southwest, Rochester, MN 55905, USA.
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42
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Laferrière F, Tixador P, Moudjou M, Chapuis J, Sibille P, Herzog L, Reine F, Jaumain E, Laude H, Rezaei H, Béringue V. Quaternary structure of pathological prion protein as a determining factor of strain-specific prion replication dynamics. PLoS Pathog 2013; 9:e1003702. [PMID: 24130496 PMCID: PMC3795044 DOI: 10.1371/journal.ppat.1003702] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Accepted: 08/27/2013] [Indexed: 11/18/2022] Open
Abstract
Prions are proteinaceous infectious agents responsible for fatal neurodegenerative diseases in animals and humans. They are essentially composed of PrP(Sc), an aggregated, misfolded conformer of the ubiquitously expressed host-encoded prion protein (PrP(C)). Stable variations in PrP(Sc) conformation are assumed to encode the phenotypically tangible prion strains diversity. However the direct contribution of PrP(Sc) quaternary structure to the strain biological information remains mostly unknown. Applying a sedimentation velocity fractionation technique to a panel of ovine prion strains, classified as fast and slow according to their incubation time in ovine PrP transgenic mice, has previously led to the observation that the relationship between prion infectivity and PrP(Sc) quaternary structure was not univocal. For the fast strains specifically, infectivity sedimented slowly and segregated from the bulk of proteinase-K resistant PrP(Sc). To carefully separate the respective contributions of size and density to this hydrodynamic behavior, we performed sedimentation at the equilibrium and varied the solubilization conditions. The density profile of prion infectivity and proteinase-K resistant PrP(Sc) tended to overlap whatever the strain, fast or slow, leaving only size as the main responsible factor for the specific velocity properties of the fast strain most infectious component. We further show that this velocity-isolable population of discrete assemblies perfectly resists limited proteolysis and that its templating activity, as assessed by protein misfolding cyclic amplification outcompetes by several orders of magnitude that of the bulk of larger size PrP(Sc) aggregates. Together, the tight correlation between small size, conversion efficiency and duration of disease establishes PrP(Sc) quaternary structure as a determining factor of prion replication dynamics. For certain strains, a subset of PrP assemblies appears to be the best template for prion replication. This has important implications for fundamental studies on prions.
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Affiliation(s)
- Florent Laferrière
- INRA (Institut National de la Recherche Agronomique), UR892, Virologie Immunologie Moléculaires, Jouy-en-Josas, France
| | - Philippe Tixador
- INRA (Institut National de la Recherche Agronomique), UR892, Virologie Immunologie Moléculaires, Jouy-en-Josas, France
| | - Mohammed Moudjou
- INRA (Institut National de la Recherche Agronomique), UR892, Virologie Immunologie Moléculaires, Jouy-en-Josas, France
| | - Jérôme Chapuis
- INRA (Institut National de la Recherche Agronomique), UR892, Virologie Immunologie Moléculaires, Jouy-en-Josas, France
| | - Pierre Sibille
- INRA (Institut National de la Recherche Agronomique), UR892, Virologie Immunologie Moléculaires, Jouy-en-Josas, France
| | - Laetitia Herzog
- INRA (Institut National de la Recherche Agronomique), UR892, Virologie Immunologie Moléculaires, Jouy-en-Josas, France
| | - Fabienne Reine
- INRA (Institut National de la Recherche Agronomique), UR892, Virologie Immunologie Moléculaires, Jouy-en-Josas, France
| | - Emilie Jaumain
- INRA (Institut National de la Recherche Agronomique), UR892, Virologie Immunologie Moléculaires, Jouy-en-Josas, France
| | - Hubert Laude
- INRA (Institut National de la Recherche Agronomique), UR892, Virologie Immunologie Moléculaires, Jouy-en-Josas, France
| | - Human Rezaei
- INRA (Institut National de la Recherche Agronomique), UR892, Virologie Immunologie Moléculaires, Jouy-en-Josas, France
| | - Vincent Béringue
- INRA (Institut National de la Recherche Agronomique), UR892, Virologie Immunologie Moléculaires, Jouy-en-Josas, France
- * E-mail:
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43
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Ramirez-Alvarado M. Amyloid formation in light chain amyloidosis. Curr Top Med Chem 2013; 12:2523-33. [PMID: 23339305 DOI: 10.2174/1568026611212220007] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2012] [Revised: 09/10/2012] [Accepted: 09/12/2012] [Indexed: 01/16/2023]
Abstract
Light chain amyloidosis is one of the unique examples within amyloid diseases where the amyloidogenic precursor is a protein that escapes the quality control machinery and is secreted from the cells to be circulated in the bloodstream. The immunoglobulin light chains are produced by an abnormally proliferative monoclonal population of plasma cells that under normal conditions produce immunoglobulin molecules such as IgG, IgM or IgA. Once the light chains are in circulation, the proteins misfold and deposit as amyloid fibrils in numerous tissues and organs, causing organ failure and death. While there is a correlation between the thermodynamic stability of the protein and the kinetics of amyloid formation, we have recently found that this correlation applies within a thermodynamic range, and it is only a helpful correlation when comparing mutants from the same protein. Light chain amyloidosis poses unique challenges because each patient has a unique protein sequence as a result of the selection of a germline gene and the incorporation of somatic mutations. The exact location of the misfolding process is unknown as well as the full characterization of all of the toxic species populated during the amyloid formation process in light chain amyloidosis.
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Affiliation(s)
- Marina Ramirez-Alvarado
- Department of Biochemistry and Molecular Biology, Mayo Clinic, 200 First St SW, Rochester, MN 55905, USA.
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44
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Borgia MB, Nickson AA, Clarke J, Hounslow MJ. A mechanistic model for amorphous protein aggregation of immunoglobulin-like domains. J Am Chem Soc 2013; 135:6456-64. [PMID: 23510407 PMCID: PMC3759167 DOI: 10.1021/ja308852b] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Protein aggregation is associated with many debilitating diseases including Alzheimer's, Parkinson's, and light-chain amyloidosis (AL). Additionally, such aggregation is a major problem in an industrial setting where antibody therapeutics often require high local concentrations of protein domains to be stable for substantial periods of time. However, despite a plethora of research in this field, dating back over 50 years, there is still no consensus on the mechanistic basis for protein aggregation. Here we use experimental data to derive a mechanistic model that well describes the aggregation of Titin I27, an immunoglobulin-like domain. Importantly, we find that models that are suitable for nucleated fibril formation do not fit our aggregation data. Instead, we show that aggregation proceeds via the addition of activated dimers, and that the rate of aggregation is dependent on the surface area of the aggregate. Moreover, we suggest that the "lag time" seen in these studies is not the time needed for a nucleation event to occur, but rather it is the time taken for the concentration of activated dimers to cross a particular solubility limit. These findings are reminiscent of the Finke-Watzky aggregation mechanism, originally based on nanocluster formation and suggest that amorphous aggregation processes may require mechanistic schemes that are substantially different from those of linear fibril formation.
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Affiliation(s)
- Madeleine B Borgia
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK
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45
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Abstract
The amyloidoses are a group of protein misfolding diseases in which the precursor protein undergoes a conformational change that triggers the formation of amyloid fibrils in different tissues and organs, causing cell death and organ failure. Amyloidoses can be either localized or systemic. In localized amyloidosis, amyloid deposits form at the site of precursor protein synthesis, whereas in systemic amyloidosis, amyloid deposition occurs distant from the site of precursor protein secretion. We review the type of proteins and cells involved and what is known about the complex pathophysiology of these diseases. We focus on light chain amyloidosis to illustrate how biochemical and biophysical studies have led to a deeper understanding of the pathogenesis of this devastating disease. We also review current cellular, tissue, and animal models and discuss the challenges and opportunities for future studies of the systemic amyloidoses.
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Affiliation(s)
- Luis M Blancas-Mejía
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota 55905, USA.
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46
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Deva T, Lorenzen N, Vad BS, Petersen SV, Thørgersen I, Enghild JJ, Kristensen T, Otzen DE. Off-pathway aggregation can inhibit fibrillation at high protein concentrations. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2013; 1834:677-87. [PMID: 23313095 DOI: 10.1016/j.bbapap.2012.12.020] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2012] [Revised: 12/11/2012] [Accepted: 12/28/2012] [Indexed: 11/24/2022]
Abstract
Ribosomal protein S6 fibrillates readily at slightly elevated temperatures and acidic pH. We find that S6 fibrillation is retarded rather than favored when the protein concentration is increased above a threshold concentration of around 3.5mg/mL. We name this threshold concentration C(FR), the concentration at which fibrillation is retarded. Our data are consistent with a model in which this inhibition is due to the formation of an off-pathway oligomeric species with native-like secondary structure. The oligomeric species dominates at high protein concentrations but exists in dynamic equilibrium with the monomer so that seeding with fibrils can overrule oligomer formation and favors fibrillation under C(FR) conditions. Thus, fibrillation competes with formation of off-pathway oligomers, probably due to a monomeric conversion step that is required to commit the protein to the fibrillation pathway. The S6 oligomer is resistant to pepsin digestion. We also report that S6 forms different types of fibrils dependent on protein concentration. Our observations highlight the multitude of conformational states available to proteins under destabilizing conditions.
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Affiliation(s)
- Taru Deva
- Center for Insoluble Protein Structures (inSPIN), Interdisciplinary Nanoscience Center (iNANO), Department of Molecular Biology and Genetics, University of Aarhus, Gustav Wieds Vej 14, DK-8000 Aarhus C, Denmark.
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47
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In vitro aggregation behavior of a non-amyloidogenic λ light chain dimer deriving from U266 multiple myeloma cells. PLoS One 2012; 7:e33372. [PMID: 22432016 PMCID: PMC3303827 DOI: 10.1371/journal.pone.0033372] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2011] [Accepted: 02/14/2012] [Indexed: 11/19/2022] Open
Abstract
Excessive production of monoclonal light chains due to multiple myeloma can induce aggregation-related disorders, such as light chain amyloidosis (AL) and light chain deposition diseases (LCDD). In this work, we produce a non-amyloidogenic IgE λ light chain dimer from human mammalian cells U266, which originated from a patient suffering from multiple myeloma, and we investigate the effect of several physicochemical parameters on the in vitro stability of this protein. The dimer is stable in physiological conditions and aggregation is observed only when strong denaturating conditions are applied (acidic pH with salt at large concentration or heating at melting temperature Tm at pH 7.4). The produced aggregates are spherical, amorphous oligomers. Despite the larger β-sheet content of such oligomers with respect to the native state, they do not bind Congo Red or ThT. The impossibility to obtain fibrils from the light chain dimer suggests that the occurrence of amyloidosis in patients requires the presence of the light chain fragment in the monomer form, while dimer can form only amorphous oligomers or amorphous deposits. No aggregation is observed after denaturant addition at pH 7.4 or at pH 2.0 with low salt concentration, indicating that not a generic unfolding but specific conformational changes are necessary to trigger aggregation. A specific anion effect in increasing the aggregation rate at pH 2.0 is observed according to the following order: SO4−≫Cl−>H2PO4−, confirming the peculiar role of sulfate in promoting protein aggregation. It is found that, at least for the investigated case, the mechanism of the sulfate effect is related to protein secondary structure changes induced by anion binding.
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48
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Bemporad F, Chiti F. Protein Misfolded Oligomers: Experimental Approaches, Mechanism of Formation, and Structure-Toxicity Relationships. ACTA ACUST UNITED AC 2012; 19:315-27. [DOI: 10.1016/j.chembiol.2012.02.003] [Citation(s) in RCA: 215] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2011] [Revised: 01/30/2012] [Accepted: 02/01/2012] [Indexed: 11/30/2022]
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Muzaffar M, Ahmad A. The mechanism of enhanced insulin amyloid fibril formation by NaCl is better explained by a conformational change model. PLoS One 2011; 6:e27906. [PMID: 22132167 PMCID: PMC3221682 DOI: 10.1371/journal.pone.0027906] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2011] [Accepted: 10/27/2011] [Indexed: 01/05/2023] Open
Abstract
The high propensity of insulin to fibrillate causes severe biomedical and biotechnological complications. Insulin fibrillation studies attain significant importance considering the prevalence of diabetes and the requirement of functional insulin in each dose. Although studied since the early years of the 20(th) century, elucidation of the mechanism of insulin fibrillation has not been understood completely. We have previously, through several studies, shown that insulin hexamer dissociates into monomer that undergoes partial unfolding before converting into mature fibrils. In this study we have established that NaCl enhances insulin fibrillation mainly due to subtle structural changes and is not a mere salt effect. We have carried out studies both in the presence and absence of urea and Gdn.HCl and compared the relationship between conformation of insulin induced by urea and Gdn.HCl with respect to NaCl at both pH 7.4 (hexamer) and pH 2 (monomer). Fibril formation was followed with a Thioflavin T assay and structural changes were monitored by circular dichroism and size-exclusion chromatography. The results show salt-insulin interactions are difficult to classify as commonly accepted Debye-Hückel or Hofmeister series interactions but instead a strong correlation between the association states and conformational states of insulin and their propensity to fibrillate is evident.
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Affiliation(s)
- Mahvish Muzaffar
- Department of Biological Chemistry and Life Sciences Institute, University of Michigan, Ann Arbor, Michigan, United States of America
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50
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Mukherjee S, Pondaven SP, Jaroniec CP. Conformational Flexibility of a Human Immunoglobulin Light Chain Variable Domain by Relaxation Dispersion Nuclear Magnetic Resonance Spectroscopy: Implications for Protein Misfolding and Amyloid Assembly. Biochemistry 2011; 50:5845-57. [DOI: 10.1021/bi200410c] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Sujoy Mukherjee
- Department of Chemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Simon P. Pondaven
- Department of Chemistry, The Ohio State University, Columbus, Ohio 43210, United States
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