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Namba N, Ohgita T, Tamagaki-Asahina H, Nishitsuji K, Shimanouchi T, Sato T, Saito H. Amyloidogenic 60-71 deletion/ValThr insertion mutation of apolipoprotein A-I generates a new aggregation-prone segment that promotes nucleation through entropic effects. Sci Rep 2023; 13:18514. [PMID: 37898709 PMCID: PMC10613298 DOI: 10.1038/s41598-023-45803-y] [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: 07/31/2023] [Accepted: 10/24/2023] [Indexed: 10/30/2023] Open
Abstract
The N-terminal fragment of apolipoprotein A-I (apoA-I), comprising residues 1-83, contains three segments prone to aggregation: residues 14-22, 53-58, and 67-72. We previously demonstrated that residues 14-22 are critical in apoA-I fibril formation while residues 53-58 entropically drove the nucleation process. Here, we investigated the impact of amyloidogenic mutations (Δ60-71/VT, Δ70-72, and F71Y) located around residues 67-72 on fibril formation by the apoA-I 1-83 fragment. Thioflavin T fluorescence assay demonstrated that the Δ60-71/VT mutation significantly enhances both nucleation and fibril elongation rates, whereas the Δ70-72 and F71Y mutations had minimal effects. Circular dichroism measurements and microscopic observations revealed that all variant fragments formed straight fibrils, transitioning from random coils to β-sheet structures. Kinetic analysis demonstrated that primary nucleation is the dominant step in fibril formation, with fibril elongation reaching saturation at high protein concentrations. Thermodynamically, both nucleation and fibril elongation were enthalpically and entropically unfavorable in all apoA-I 1-83 variants, in which the entropic barrier of nucleation was almost eliminated for the Δ60-71/VT variant. Taken together, our results suggest the presence of new aggregation-prone segment in the Δ60-71/VT variant that promotes nucleation through entropic effects.
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Affiliation(s)
- Norihiro Namba
- Laboratory of Biophysical Chemistry, Kyoto Pharmaceutical University, 5 Misasagi-Nakauchi-cho, Yamashina-ku, Kyoto, 607-8414, Japan
| | - Takashi Ohgita
- Laboratory of Biophysical Chemistry, Kyoto Pharmaceutical University, 5 Misasagi-Nakauchi-cho, Yamashina-ku, Kyoto, 607-8414, Japan
| | - Hiroko Tamagaki-Asahina
- Division of Liberal Arts Sciences, Kyoto Pharmaceutical University, 5 Misasagi-Nakauchi-cho, Yamashina-ku, Kyoto, 607-8414, Japan
| | - Kazuchika Nishitsuji
- Department of Biochemistry, Wakayama Medical University, 811-1 Kimiidera, Wakayama, 641-8509, Japan
| | - Toshinori Shimanouchi
- Graduate School of Environmental and Life Science, Okayama University, Okayama, 700-8530, Japan
| | - Takeshi Sato
- Division of Liberal Arts Sciences, Kyoto Pharmaceutical University, 5 Misasagi-Nakauchi-cho, Yamashina-ku, Kyoto, 607-8414, Japan
| | - Hiroyuki Saito
- Laboratory of Biophysical Chemistry, Kyoto Pharmaceutical University, 5 Misasagi-Nakauchi-cho, Yamashina-ku, Kyoto, 607-8414, Japan.
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Bhale AS, Venkataraman K. Leveraging knowledge of HDLs major protein ApoA1: Structure, function, mutations, and potential therapeutics. Biomed Pharmacother 2022; 154:113634. [PMID: 36063649 DOI: 10.1016/j.biopha.2022.113634] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Revised: 08/27/2022] [Accepted: 08/30/2022] [Indexed: 11/02/2022] Open
Abstract
Apolipoprotein A1 (ApoA1) is a member of the Apolipoprotein family of proteins. It's a vital protein that helps in the production of high-density lipoprotein (HDL) particles, which are crucial for reverse cholesterol transport (RCT). It also has anti-inflammatory, anti-atherogenic, anti-apoptotic, and anti-thrombotic properties. These functions interact to give HDL particles their cardioprotective characteristics. ApoA1 has recently been investigated for its potential role in atherosclerosis, diabetes, neurological diseases, cancer, and certain infectious diseases. Since ApoA1's discovery, numerous mutations have been reported that affect its structural integrity and alter its function. Hence these insights have led to the development of clinically relevant peptides and synthetic reconstituted HDL (rHDL) that mimics the function of ApoA1. As a result, this review has aimed to provide an organized explanation of our understanding of the ApoA1 protein structure and its role in various essential pathways. Furthermore, we have comprehensively reviewed the important ApoA1 mutations (24 mutations) that are reported to be involved in various diseases. Finally, we've focused on the therapeutic potentials of some of the beneficial mutations, small peptides, and synthetic rHDL that are currently being researched or developed, since these will aid in the development of novel therapeutics in the future.
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Affiliation(s)
- Aishwarya Sudam Bhale
- Centre for Bio-Separation Technology, Vellore Institute of Technology, Vellore 632014, Tamil Nadu, India
| | - Krishnan Venkataraman
- Centre for Bio-Separation Technology, Vellore Institute of Technology, Vellore 632014, Tamil Nadu, India.
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Del Giudice R, Imbimbo P, Pietrocola F, Martins I, De Palma FDE, Bravo-San Pedro JM, Kroemer G, Maiuri MC, Monti DM. Autophagy Alteration in ApoA-I Related Systemic Amyloidosis. Int J Mol Sci 2022; 23:ijms23073498. [PMID: 35408859 PMCID: PMC8998969 DOI: 10.3390/ijms23073498] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 03/16/2022] [Accepted: 03/18/2022] [Indexed: 02/06/2023] Open
Abstract
Amyloidoses are characterized by the accumulation and aggregation of misfolded proteins into fibrils in different organs, leading to cell death and consequent organ dysfunction. The specific substitution of Leu 75 for Pro in Apolipoprotein A-I protein sequence (ApoA-I; L75P-ApoA-I) results in late onset amyloidosis, where deposition of extracellular protein aggregates damages the normal functions of the liver. In this work, we describe that the autophagic process is inhibited in the presence of the L75P-ApoA-I amyloidogenic variant in stably transfected human hepatocyte carcinoma cells. The L75P-ApoA-I amyloidogenic variant alters the redox status of the cells, resulting into excessive mitochondrial stress and consequent cell death. Moreover, L75P-ApoA-I induces an impairment of the autophagic flux. Pharmacological induction of autophagy or transfection-enforced overexpression of the pro-autophagic transcription factor EB (TFEB) restores proficient proteostasis and reduces oxidative stress in these experimental settings, suggesting that pharmacological stimulation of autophagy could be a promising target to alleviate ApoA-I amyloidosis.
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Affiliation(s)
- Rita Del Giudice
- Department of Chemical Sciences, University of Napoli Federico II, Complesso Universitario Monte Sant’Angelo, 80126 Napoli, Italy; (R.D.G.); (P.I.)
| | - Paola Imbimbo
- Department of Chemical Sciences, University of Napoli Federico II, Complesso Universitario Monte Sant’Angelo, 80126 Napoli, Italy; (R.D.G.); (P.I.)
| | - Federico Pietrocola
- Department of Biosciences and Nutrition, Karolinska Institute, 14157 Huddinge, Sweden;
| | - Isabelle Martins
- Centre de Recherche des Cordeliers, INSERM U1138, Université Paris Cité, Sorbonne Université, 75006 Paris, France; (I.M.); (F.D.E.D.P.); (G.K.); (M.C.M.)
- Metabolomics and Cell Biology Platforms, Gustave Roussy Cancer Campus, 94805 Villejuif, France
| | - Fatima Domenica Elisa De Palma
- Centre de Recherche des Cordeliers, INSERM U1138, Université Paris Cité, Sorbonne Université, 75006 Paris, France; (I.M.); (F.D.E.D.P.); (G.K.); (M.C.M.)
- CEINGE-Biotecnologie Avanzate s.c.a.r.l., 80145 Napoli, Italy
- Department of Molecular Medicine and Medical Biotechnologies, University of Napoli Federico II, 80131 Napoli, Italy
| | | | - Guido Kroemer
- Centre de Recherche des Cordeliers, INSERM U1138, Université Paris Cité, Sorbonne Université, 75006 Paris, France; (I.M.); (F.D.E.D.P.); (G.K.); (M.C.M.)
- Metabolomics and Cell Biology Platforms, Gustave Roussy Cancer Campus, 94805 Villejuif, France
- Institut Universitaire de France, 75005 Paris, France
- Pôle de Biologie, Hôpital Européen Georges Pompidou, Ap-hp, 75015 Paris, France
| | - Maria Chiara Maiuri
- Centre de Recherche des Cordeliers, INSERM U1138, Université Paris Cité, Sorbonne Université, 75006 Paris, France; (I.M.); (F.D.E.D.P.); (G.K.); (M.C.M.)
- Metabolomics and Cell Biology Platforms, Gustave Roussy Cancer Campus, 94805 Villejuif, France
- Pharmacy Department, University of Napoli Federico II, 80131 Napoli, Italy
| | - Daria Maria Monti
- Department of Chemical Sciences, University of Napoli Federico II, Complesso Universitario Monte Sant’Angelo, 80126 Napoli, Italy; (R.D.G.); (P.I.)
- Istituto Nazionale di Biostrutture e Biosistemi (INBB), 00136 Rome, Italy
- Correspondence:
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Lewkowicz E, Gursky O. Dynamic protein structures in normal function and pathologic misfolding in systemic amyloidosis. Biophys Chem 2022; 280:106699. [PMID: 34773861 PMCID: PMC9416430 DOI: 10.1016/j.bpc.2021.106699] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Revised: 10/08/2021] [Accepted: 10/08/2021] [Indexed: 02/08/2023]
Abstract
Dynamic and disordered regions in native proteins are often critical for their function, particularly in ligand binding and signaling. In certain proteins, however, such regions can contribute to misfolding and pathologic deposition as amyloid fibrils in vivo. For example, dynamic and disordered regions can promote amyloid formation by destabilizing the native structure, by directly triggering the aggregation, by promoting protein condensation, or by acting as sites of early proteolytic cleavage that favor a release of aggregation-prone fragments or facilitate fibril maturation. At the same time, enhanced dynamics in the native protein state accelerates proteolytic degradation that counteracts amyloid accumulation in vivo. Therefore, the functional need for dynamic protein regions must be balanced against their inherently labile nature. How exactly this balance is achieved and how is it shifted upon amyloidogenic mutations or post-translational modifications? To illustrate possible scenarios, here we review the beneficial and pathologic roles of dynamic and disordered regions in the native states of three families of human plasma proteins that form amyloid precursors in systemic amyloidoses: immunoglobulin light chain, apolipoproteins, and serum amyloid A. Analysis of structure, stability and local dynamics of these diverse proteins and their amyloidogenic variants exemplifies how disordered/dynamic regions can provide a functional advantage as well as an Achilles heel in pathologic amyloid formation.
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Gisonno RA, Masson T, Ramella NA, Barrera EE, Romanowski V, Tricerri MA. Evolutionary and structural constraints influencing apolipoprotein A-I amyloid behavior. Proteins 2021; 90:258-269. [PMID: 34414600 DOI: 10.1002/prot.26217] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Revised: 07/27/2021] [Accepted: 08/09/2021] [Indexed: 12/13/2022]
Abstract
Apolipoprotein A-I (apoA-I) has a key function in the reverse cholesterol transport. However, aggregation of apoA-I single point mutants can lead to hereditary amyloid pathology. Although several studies have tackled the biophysical and structural consequences introduced by these mutations, there is little information addressing the relationship between the evolutionary and structural features that contribute to the amyloid behavior of apoA-I. We combined evolutionary studies, in silico mutagenesis and molecular dynamics (MD) simulations to provide a comprehensive analysis of the conservation and pathogenic role of the aggregation-prone regions (APRs) present in apoA-I. Sequence analysis demonstrated that among the four amyloidogenic regions described for human apoA-I, only two (APR1 and APR4) are evolutionary conserved across different species of Sarcopterygii. Moreover, stability analysis carried out with the FoldX engine showed that APR1 contributes to the marginal stability of apoA-I. Structural properties of full-length apoA-I models suggest that aggregation is avoided by placing APRs into highly packed and rigid portions of its native fold. Compared to silent variants extracted from the gnomAD database, the thermodynamic and pathogenic impact of amyloid mutations showed evidence of a higher destabilizing effect. MD simulations of the amyloid variant G26R evidenced the partial unfolding of the alpha-helix bundle with the concomitant exposure of APR1 to the solvent, suggesting an insight into the early steps involved in its aggregation. Our findings highlight APR1 as a relevant component for apoA-I structural integrity and emphasize a destabilizing effect of amyloid variants that leads to the exposure of this region.
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Affiliation(s)
- Romina A Gisonno
- Facultad de Ciencias Médicas, Instituto de Investigaciones Bioquímicas de La Plata (INIBIOLP, CONICET-UNLP), Universidad Nacional de La Plata, La Plata, Argentina
| | - Tomas Masson
- Facultad de Ciencias Exactas, Instituto de Biotecnología y Biología Molecular (IBBM, CONICET-UNLP), Universidad Nacional de La Plata, La Plata, Argentina
| | - Nahuel A Ramella
- Facultad de Ciencias Médicas, Instituto de Investigaciones Bioquímicas de La Plata (INIBIOLP, CONICET-UNLP), Universidad Nacional de La Plata, La Plata, Argentina
| | - Exequiel E Barrera
- Group of Biomolecular Simulations, Institut Pasteur de Montevideo, Montevideo, Uruguay
| | - Víctor Romanowski
- Facultad de Ciencias Exactas, Instituto de Biotecnología y Biología Molecular (IBBM, CONICET-UNLP), Universidad Nacional de La Plata, La Plata, Argentina
| | - M Alejandra Tricerri
- Facultad de Ciencias Médicas, Instituto de Investigaciones Bioquímicas de La Plata (INIBIOLP, CONICET-UNLP), Universidad Nacional de La Plata, La Plata, Argentina
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6
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Ohgita T, Furutani Y, Nakano M, Hattori M, Suzuki A, Nakagawa M, Naniwa S, Morita I, Oyama H, Nishitsuji K, Kobayashi N, Saito H. Novel conformation‐selective monoclonal antibodies against apoA‐I amyloid fibrils. FEBS J 2021. [DOI: 10.1111/febs.15487] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Takashi Ohgita
- Department of Biophysical Chemistry Kyoto Pharmaceutical University Japan
| | - Yuki Furutani
- Department of Biophysical Chemistry Kyoto Pharmaceutical University Japan
| | - Miyu Nakano
- Department of Biophysical Chemistry Kyoto Pharmaceutical University Japan
| | - Megumi Hattori
- Department of Biophysical Chemistry Kyoto Pharmaceutical University Japan
| | - Ayane Suzuki
- Department of Biophysical Chemistry Kyoto Pharmaceutical University Japan
| | - Miho Nakagawa
- Department of Biophysical Chemistry Kyoto Pharmaceutical University Japan
| | - Sera Naniwa
- Department of Bioanalytical Chemistry Kobe Pharmaceutical University Japan
| | - Izumi Morita
- Department of Bioanalytical Chemistry Kobe Pharmaceutical University Japan
| | - Hiroyuki Oyama
- Department of Bioanalytical Chemistry Kobe Pharmaceutical University Japan
| | | | - Norihiro Kobayashi
- Department of Bioanalytical Chemistry Kobe Pharmaceutical University Japan
| | - Hiroyuki Saito
- Department of Biophysical Chemistry Kyoto Pharmaceutical University Japan
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7
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Delbarba A, Facondo P, Fisogni S, Izzi C, Maffezzoni F, Pezzaioli LC, Di Lodovico E, Facchetti F, Cappelli C, Scolari F, Ferlin A. Testicular Involvement is a Hallmark of Apo A-I Leu75Pro Mutation Amyloidosis. J Clin Endocrinol Metab 2020; 105:5897040. [PMID: 32841328 DOI: 10.1210/clinem/dgaa587] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 08/19/2020] [Indexed: 01/19/2023]
Abstract
CONTEXT Apo A-I Leu75Pro is a rare hereditary form of amyloidosis that mainly involves the kidney, the liver, and the testis. OBJECTIVE To define the characteristics of organ damage and testis impairment in the largest cohort collected to date of men with Apo A-I Leu75Pro amyloidosis. DESIGN, SETTING, AND PATIENTS Retrospective study from a prospectively collected database of 129 male subjects >18 years with Apo A-I Leu75Pro amyloidosis from a reference center at the University Hospital of Brescia, Italy. MAIN OUTCOME MEASURES We evaluated liver and renal function, scrotal ultrasound, reproductive hormone levels, testis biopsy, hypogonadal symptoms, and fertility. RESULTS Progressive involvement of testis, kidney, and liver was observed in 96/129 (74.4%) cases. Testis impairment was found in 88/129 patients (68.2%), liver in 59 (45.7%) and renal in 50 (38.8%). Testis damage was often the first manifestation of the disease and the only dysfunction in 30% of younger patients (<38 years). Testicular involvement was characterized mainly by primary (73/88 patients, 83.0%) and subclinical (8/88, 9.1%) hypogonadism. Almost all (85/88, 96.6%) also had high follicle-stimulating hormone, suggesting a primary global damage of endocrine and spermatogenic functions, and 30% of them did not conceive. Macroorchidism was found in 53/88 (60.2%) patients, especially in men <54 years (30/33, 90.9%). Apo A-I amyloid deposits were found in Sertoli cells, germinal epithelium, and vessel walls. CONCLUSION In men with Apo A-I Leu75Pro amyloidosis, testicular involvement is the hallmark of the disease, characterized by global primary testicular dysfunction and macroorchidism due to amyloid deposits.
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Affiliation(s)
- Andrea Delbarba
- Unit of Endocrinology and Metabolism, ASST Spedali Civili Brescia, Brescia, Italy
| | - Paolo Facondo
- Department of Clinical and Experimental Sciences, Unit of Endocrinology and Metabolism, University of Brescia and ASST Spedali Civili Brescia, Brescia, Italy
| | - Simona Fisogni
- Department of Molecular and Translational Medicine, Pathology Unit, University of Brescia and ASST Spedali Civili Brescia, Brescia, Italy
| | - Claudia Izzi
- Prenatal Diagnosis Unit, Department of Obstetrics and Gynecology, ASST Spedali Civili, Brescia, Italy
- Division of Nephrology and Dialysis, Department of Medical and Surgical Specialties, Radiological Sciences and Public Health, University of Brescia and ASST Spedali Civili Brescia, Brescia, Italy
| | - Filippo Maffezzoni
- Unit of Endocrinology and Metabolism, ASST Spedali Civili Brescia, Brescia, Italy
| | - Letizia Chiara Pezzaioli
- Department of Clinical and Experimental Sciences, Unit of Endocrinology and Metabolism, University of Brescia and ASST Spedali Civili Brescia, Brescia, Italy
| | - Elena Di Lodovico
- Department of Clinical and Experimental Sciences, Unit of Endocrinology and Metabolism, University of Brescia and ASST Spedali Civili Brescia, Brescia, Italy
| | - Fabio Facchetti
- Department of Molecular and Translational Medicine, Pathology Unit, University of Brescia and ASST Spedali Civili Brescia, Brescia, Italy
| | - Carlo Cappelli
- Department of Clinical and Experimental Sciences, Unit of Endocrinology and Metabolism, University of Brescia and ASST Spedali Civili Brescia, Brescia, Italy
| | - Francesco Scolari
- Division of Nephrology and Dialysis, Department of Medical and Surgical Specialties, Radiological Sciences and Public Health, University of Brescia and ASST Spedali Civili Brescia, Brescia, Italy
| | - Alberto Ferlin
- Department of Clinical and Experimental Sciences, Unit of Endocrinology and Metabolism, University of Brescia and ASST Spedali Civili Brescia, Brescia, Italy
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Ma'arfi F, Chandra S, Fatima JE, Khan MY, Mir SS, Yusuf MA. Probing the Structure-Function relationship and amyloidogenic propensities in natural variants of apolipoprotein A-I. Biochem Biophys Rep 2020; 24:100815. [PMID: 33024841 PMCID: PMC7527581 DOI: 10.1016/j.bbrep.2020.100815] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2020] [Revised: 09/09/2020] [Accepted: 09/13/2020] [Indexed: 11/25/2022] Open
Abstract
Background Apolipoprotein A-I (apoA-I) protects against atherosclerosis and participates in the removal of excess cellular cholesterol from peripheral organs. Several naturally occurring apoA-I mutations are associated with familial systemic amyloidosis, with deposition of amyloid aggregates in peripheral organs, resulting in multiple organ failure. Systematic studies on naturally occurring variants are needed to delineate their roles and involvement in pathogenesis. Methods We performed a comparative structure–function analysis of five naturally occurring apoA-I variants and the wild-type protein. Circular dichroism, Fourier-transform infrared spectroscopy, thioflavin T and congo red fluorescence assays, thermal, chemical, and proteolytic stability assays, and 1,2-Dimyristoyl-sn-glycero-3-phosphocholine clearance analyses were used to assess the effects of mutations on the structure, function, stability, aggregation, and proteolytic susceptibility of the proteins to explore the mechanisms underlying amyloidosis and hypercholesterolemia. Results We observed structural changes in the mutants independent of fibril formation, suggesting the influence of the surrounding environment. The mutants were involved in aggregate formation to varying degree; L170P, R173P, and V156E showed an increased propensity to aggregate under different physiological conditions. β sheet formation indicates that L170P and R173P participate in amyloid formation. Compared to WT, V156E and L170P exhibited higher capacity for lipid clearance. Conclusions The selected point mutations, including those outside the hot spot regions of apoA-I structure, perturb the physiochemical and conformational behavior of the protein, influencing its function. General significance The study provides insights into the structure–function relationships of naturally occurring apoA-I variants outside the hot spot mutation sites. Several apoA-I mutants are associated with systemic amyloidosis. Structure–function analysis of five apoA-I variants and wild-type protein was done. Point mutations alter the physicochemical behavior and conformation of the variants.
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Affiliation(s)
- Farah Ma'arfi
- Department of Bioengineering, Integral University, Kursi Road, Dasauli, Lucknow, 226026, India
| | - Subhash Chandra
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110067, India
| | - Jamal e Fatima
- Department of Bioengineering, Integral University, Kursi Road, Dasauli, Lucknow, 226026, India
| | - Mohd Yasir Khan
- Department of Biosciences, Integral University, Kursi Road, Dasauli, Lucknow, 226026, India
| | - Snober S. Mir
- Department of Bioengineering, Integral University, Kursi Road, Dasauli, Lucknow, 226026, India
| | - Mohd Aslam Yusuf
- Department of Bioengineering, Integral University, Kursi Road, Dasauli, Lucknow, 226026, India
- Corresponding author. ;
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Gaddi GM, Gisonno RA, Rosú SA, Curto LM, Prieto ED, Schinella GR, Finarelli GS, Cortez MF, Bauzá L, Elías EE, Ramella NA, Tricerri MA. Structural analysis of a natural apolipoprotein A-I variant (L60R) associated with amyloidosis. Arch Biochem Biophys 2020; 685:108347. [DOI: 10.1016/j.abb.2020.108347] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2019] [Revised: 03/12/2020] [Accepted: 03/14/2020] [Indexed: 01/11/2023]
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Kurimitsu N, Mizuguchi C, Fujita K, Taguchi S, Ohgita T, Nishitsuji K, Shimanouchi T, Saito H. Phosphatidylethanolamine accelerates aggregation of the amyloidogenic N-terminal fragment of apoA-I. FEBS Lett 2020; 594:1443-1452. [PMID: 31968125 DOI: 10.1002/1873-3468.13737] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Revised: 12/28/2019] [Accepted: 01/02/2020] [Indexed: 12/13/2022]
Abstract
Membrane lipid composition is known to influence aggregation and fibril formation of many amyloidogenic proteins. Here, we found that phosphatidylethanolamine (PE) accelerates aggregation of the N-terminal 1-83 fragment of an amyloidogenic G26R variant of apoA-I on lipid membranes. Circular dichroism and isothermal titration calorimetry measurements demonstrated that PE does not affect the α-helical structure and lipid binding property of apoA-I 1-83/G26R. Rather, fluorescence measurements indicated that PE induces more ordered lipid packing at the interfacial and acyl chain regions, providing more hydrophobic environments especially around the highly amyloidogenic regions in apoA-I on the membrane surface. These results suggest that PE promotes aggregation of the amyloidogenic N-terminal fragment of apoA-I on lipid membranes by inducing hydrophobic membrane environments.
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Affiliation(s)
- Naoko Kurimitsu
- Department of Biophysical Chemistry, Kyoto Pharmaceutical University, Kyoto, Japan
| | - Chiharu Mizuguchi
- Department of Biophysical Chemistry, Kyoto Pharmaceutical University, Kyoto, Japan
| | - Kaho Fujita
- Department of Biophysical Chemistry, Kyoto Pharmaceutical University, Kyoto, Japan
| | - Suzuno Taguchi
- Graduate School of Environmental and Life Science, Okayama University, Okayama, Japan
| | - Takashi Ohgita
- Department of Biophysical Chemistry, Kyoto Pharmaceutical University, Kyoto, Japan
| | | | - Toshinori Shimanouchi
- Graduate School of Environmental and Life Science, Okayama University, Okayama, Japan
| | - Hiroyuki Saito
- Department of Biophysical Chemistry, Kyoto Pharmaceutical University, Kyoto, Japan
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11
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Mizuguchi C, Nakagawa M, Namba N, Sakai M, Kurimitsu N, Suzuki A, Fujita K, Horiuchi S, Baba T, Ohgita T, Nishitsuji K, Saito H. Mechanisms of aggregation and fibril formation of the amyloidogenic N-terminal fragment of apolipoprotein A-I. J Biol Chem 2019; 294:13515-13524. [PMID: 31341020 DOI: 10.1074/jbc.ra119.008000] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2019] [Revised: 07/20/2019] [Indexed: 01/26/2023] Open
Abstract
The N-terminal (1-83) fragment of the major constituent of plasma high-density lipoprotein, apolipoprotein A-I (apoA-I), strongly tends to form amyloid fibrils, leading to systemic amyloidosis. Here, using a series of deletion variants, we examined the roles of two major amyloidogenic segments (residues 14-22 and 50-58) in the aggregation and fibril formation of an amyloidogenic G26R variant of the apoA-I 1-83 fragment (apoA-I 1-83/G26R). Thioflavin T fluorescence assays and atomic force microscopy revealed that elimination of residues 14-22 completely inhibits fibril formation of apoA-I 1-83/G26R, whereas Δ32-40 and Δ50-58 variants formed fibrils with markedly reduced nucleation and fibril growth rates. CD measurements revealed structural transitions from random coil to β-sheet structures in all deletion variants except for the Δ14-22 variant, indicating that residues 14-22 are critical for the β-transition and fibril formation. Thermodynamic analysis of the kinetics of fibril formation by apoA-I 1-83/G26R indicated that both nucleation and fibril growth are enthalpically unfavorable, whereas entropically, nucleation is favorable, but fibril growth is unfavorable. Interestingly, the nucleation of the Δ50-58 variant was entropically unfavorable, indicating that residues 50-58 entropically promote the nucleation step in fibril formation of apoA-I 1-83/G26R. Moreover, a residue-level structural investigation of apoA-I 1-83/G26R fibrils with site-specific pyrene labeling indicated that the two amyloidogenic segments are in close proximity to form an amyloid core structure, whereas the N- and C-terminal tail regions are excluded from the amyloid core. These results provide critical insights into the aggregation mechanism and fibril structure of the amyloidogenic N-terminal fragment of apoA-I.
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Affiliation(s)
- Chiharu Mizuguchi
- Department of Biophysical Chemistry, Kyoto Pharmaceutical University, 5 Misasagi-Nakauchi-cho, Yamashina-ku, Kyoto 607-8414, Japan
| | - Miho Nakagawa
- Department of Biophysical Chemistry, Kyoto Pharmaceutical University, 5 Misasagi-Nakauchi-cho, Yamashina-ku, Kyoto 607-8414, Japan
| | - Norihiro Namba
- Department of Biophysical Chemistry, Kyoto Pharmaceutical University, 5 Misasagi-Nakauchi-cho, Yamashina-ku, Kyoto 607-8414, Japan
| | - Misae Sakai
- Department of Biophysical Chemistry, Kyoto Pharmaceutical University, 5 Misasagi-Nakauchi-cho, Yamashina-ku, Kyoto 607-8414, Japan
| | - Naoko Kurimitsu
- Department of Biophysical Chemistry, Kyoto Pharmaceutical University, 5 Misasagi-Nakauchi-cho, Yamashina-ku, Kyoto 607-8414, Japan
| | - Ayane Suzuki
- Department of Biophysical Chemistry, Kyoto Pharmaceutical University, 5 Misasagi-Nakauchi-cho, Yamashina-ku, Kyoto 607-8414, Japan
| | - Kaho Fujita
- Department of Biophysical Chemistry, Kyoto Pharmaceutical University, 5 Misasagi-Nakauchi-cho, Yamashina-ku, Kyoto 607-8414, Japan
| | - Sayaka Horiuchi
- Department of Biophysical Chemistry, Kyoto Pharmaceutical University, 5 Misasagi-Nakauchi-cho, Yamashina-ku, Kyoto 607-8414, Japan
| | - Teruhiko Baba
- Biotechnology Research Institute for Drug Discovery, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba Central 5, 1-1-1 Higashi, Tsukuba 305-8565, Japan
| | - Takashi Ohgita
- Department of Biophysical Chemistry, Kyoto Pharmaceutical University, 5 Misasagi-Nakauchi-cho, Yamashina-ku, Kyoto 607-8414, Japan
| | - Kazuchika Nishitsuji
- Department of Biochemistry, Wakayama Medical University, 811-1 Kimiidera, Wakayama 641-8509, Japan
| | - Hiroyuki Saito
- Department of Biophysical Chemistry, Kyoto Pharmaceutical University, 5 Misasagi-Nakauchi-cho, Yamashina-ku, Kyoto 607-8414, Japan.
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12
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Wang W, Roberts CJ. Protein aggregation – Mechanisms, detection, and control. Int J Pharm 2018; 550:251-268. [DOI: 10.1016/j.ijpharm.2018.08.043] [Citation(s) in RCA: 100] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Revised: 08/18/2018] [Accepted: 08/20/2018] [Indexed: 12/19/2022]
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13
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Gorbenko GP, Trusova V, Mizuguchi C, Saito H. Lipid Bilayer Interactions of Amyloidogenic N-Terminal Fragment of Apolipoprotein A-I Probed by Förster Resonance Energy Transfer and Molecular Dynamics Simulations. J Fluoresc 2018; 28:1037-1047. [DOI: 10.1007/s10895-018-2267-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2018] [Accepted: 07/10/2018] [Indexed: 11/25/2022]
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14
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Townsend D, Hughes E, Akien G, Stewart KL, Radford SE, Rochester D, Middleton DA. Epigallocatechin-3-gallate remodels apolipoprotein A-I amyloid fibrils into soluble oligomers in the presence of heparin. J Biol Chem 2018; 293:12877-12893. [PMID: 29853648 PMCID: PMC6102129 DOI: 10.1074/jbc.ra118.002038] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Revised: 05/25/2018] [Indexed: 11/06/2022] Open
Abstract
Amyloid deposits of WT apolipoprotein A-I (apoA-I), the main protein component of high-density lipoprotein, accumulate in atherosclerotic plaques where they may contribute to coronary artery disease by increasing plaque burden and instability. Using CD analysis, solid-state NMR spectroscopy, and transmission EM, we report here a surprising cooperative effect of heparin and the green tea polyphenol (-)-epigallocatechin-3-gallate (EGCG), a known inhibitor and modulator of amyloid formation, on apoA-I fibrils. We found that heparin, a proxy for glycosaminoglycan (GAG) polysaccharides that co-localize ubiquitously with amyloid in vivo, accelerates the rate of apoA-I formation from monomeric protein and associates with insoluble fibrils. Mature, insoluble apoA-I fibrils bound EGCG (KD = 30 ± 3 μm; Bmax = 40 ± 3 μm), but EGCG did not alter the kinetics of apoA-I amyloid assembly from monomer in the presence or absence of heparin. EGCG selectively increased the mobility of specific backbone and side-chain sites of apoA-I fibrils formed in the absence of heparin, but the fibrils largely retained their original morphology and remained insoluble. By contrast, fibrils formed in the presence of heparin were mobilized extensively by the addition of equimolar EGCG, and the fibrils were remodeled into soluble 20-nm-diameter oligomers with a largely α-helical structure that were nontoxic to human umbilical artery endothelial cells. These results argue for a protective effect of EGCG on apoA-I amyloid associated with atherosclerosis and suggest that EGCG-induced remodeling of amyloid may be tightly regulated by GAGs and other amyloid co-factors in vivo, depending on EGCG bioavailability.
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Affiliation(s)
- David Townsend
- Department of Chemistry, Lancaster University, Lancaster LA1 4YB
| | - Eleri Hughes
- Department of Chemistry, Lancaster University, Lancaster LA1 4YB
| | - Geoffrey Akien
- Department of Chemistry, Lancaster University, Lancaster LA1 4YB
| | - Katie L Stewart
- Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Sheena E Radford
- Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - David Rochester
- Department of Chemistry, Lancaster University, Lancaster LA1 4YB
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15
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Effect of Phosphatidylserine and Cholesterol on Membrane-mediated Fibril Formation by the N-terminal Amyloidogenic Fragment of Apolipoprotein A-I. Sci Rep 2018; 8:5497. [PMID: 29615818 PMCID: PMC5882889 DOI: 10.1038/s41598-018-23920-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Accepted: 03/22/2018] [Indexed: 01/31/2023] Open
Abstract
Here, we examined the effects of phosphatidylserine (PS) and cholesterol on the fibril-forming properties of the N-terminal 1‒83 fragment of an amyloidogenic G26R variant of apoA-I bound to small unilamellar vesicles. A thioflavin T fluorescence assay together with microscopic observations showed that PS significantly retards the nucleation step in fibril formation by apoA-I 1‒83/G26R, whereas cholesterol slightly enhances fibril formation. Circular dichroism analyses demonstrated that PS facilitates a structural transition from random coil to α-helix in apoA-I 1‒83/G26R with great stabilization of the α-helical structure upon lipid binding. Isothermal titration calorimetry measurements revealed that PS induces a marked increase in capacity for binding of apoA-I 1‒83/G26R to the membrane surface, perhaps due to electrostatic interactions of positively charged amino acids in apoA-I with PS. Such effects of PS to enhance lipid interactions and inhibit fibril formation of apoA-I were also observed for the amyloidogenic region-containing apoA-I 8‒33/G26R peptide. Fluorescence measurements using environment-sensitive probes indicated that PS induces a more solvent-exposed, membrane-bound conformation in the amyloidogenic region of apoA-I without affecting membrane fluidity. Since cell membranes have highly heterogeneous lipid compositions, our findings may provide a molecular basis for the preferential deposition of apoA-I amyloid fibrils in tissues and organs.
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16
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Katina NS, Balobanov VA, Ilyina NB, Vasiliev VD, Marchenkov VV, Glukhov AS, Nikulin AD, Bychkova VE. sw ApoMb Amyloid Aggregation under Nondenaturing Conditions: The Role of Native Structure Stability. Biophys J 2017; 113:991-1001. [PMID: 28877500 DOI: 10.1016/j.bpj.2017.07.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Revised: 07/19/2017] [Accepted: 07/20/2017] [Indexed: 12/17/2022] Open
Abstract
Investigation of the molecular mechanisms underlying amyloid-related human diseases attracts close attention. These diseases, the number of which currently is above 40, are characterized by formation of peptide or protein aggregates containing a cross-β structure. Most of the amyloidogenesis mechanisms described so far are based on experimental studies of aggregation of short peptides, intrinsically disordered proteins, or proteins under denaturing conditions, and studies of amyloid aggregate formations by structured globular proteins under conditions close to physiological ones are still in the initial stage. We investigated the effect of amino acid substitutions on propensity of the completely helical protein sperm whale apomyoglobin (sw ApoMb) for amyloid formation from its structured state in the absence of denaturing agents. Stability and aggregation of mutated sw ApoMb were studied using circular dichroism, Fourier transform infrared spectroscopy, x-ray diffraction, native electrophoresis, and electron microscopy techniques. Here, we demonstrate that stability of the protein native state determines both protein aggregation propensity and structural peculiarities of formed aggregates. Specifically, structurally stable mutants show low aggregation propensity and moderately destabilized sw ApoMb variants form amyloids, whereas their strongly destabilized mutants form both amyloids and nonamyloid aggregates.
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Affiliation(s)
- Natalya S Katina
- Institute of Protein Research, Russian Academy of Sciences, Pushchino, Moscow Region, Russia
| | - Vitalii A Balobanov
- Institute of Protein Research, Russian Academy of Sciences, Pushchino, Moscow Region, Russia
| | - Nelly B Ilyina
- Institute of Protein Research, Russian Academy of Sciences, Pushchino, Moscow Region, Russia
| | - Victor D Vasiliev
- Institute of Protein Research, Russian Academy of Sciences, Pushchino, Moscow Region, Russia
| | - Victor V Marchenkov
- Institute of Protein Research, Russian Academy of Sciences, Pushchino, Moscow Region, Russia
| | - Anatoly S Glukhov
- Institute of Protein Research, Russian Academy of Sciences, Pushchino, Moscow Region, Russia
| | - Alexey D Nikulin
- Institute of Protein Research, Russian Academy of Sciences, Pushchino, Moscow Region, Russia
| | - Valentina E Bychkova
- Institute of Protein Research, Russian Academy of Sciences, Pushchino, Moscow Region, Russia.
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17
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Gaglione R, Smaldone G, Di Girolamo R, Piccoli R, Pedone E, Arciello A. Cell milieu significantly affects the fate of AApoAI amyloidogenic variants: predestination or serendipity? Biochim Biophys Acta Gen Subj 2017; 1862:377-384. [PMID: 29174954 DOI: 10.1016/j.bbagen.2017.11.018] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Revised: 11/17/2017] [Accepted: 11/21/2017] [Indexed: 12/12/2022]
Abstract
BACKGROUND Specific apolipoprotein A-I variants are associated to severe hereditary amyloidoses. The organ distribution of AApoAI amyloidosis seems to depend on the position of the mutation, since mutations in residues from 1 to 75 are mainly associated to hepatic and renal amyloidosis, while mutations in residues from 173 to 178 are mostly responsible for cardiac, laryngeal, and cutaneous amyloidosis. Molecular bases of this tissue specificity are still poorly understood, but it is increasingly emerging that protein destabilization induced by amyloidogenic mutations is neither necessary nor sufficient for amyloidosis development. METHODS By using a multidisciplinary approach, including circular dichroism, dynamic light scattering, spectrofluorometric and atomic force microscopy analyses, the effect of target cells on the conformation and fibrillogenic pathway of the two AApoAI amyloidogenic variants AApoAIL75P and AApoAIL174S has been monitored. RESULTS Our data show that specific cell milieus selectively affect conformation, aggregation propensity and fibrillogenesis of the two AApoAI amyloidogenic variants. CONCLUSIONS An intriguing picture emerged indicating that defined cell contexts selectively induce fibrillogenesis of specific AApoAI variants. GENERAL SIGNIFICANCE An innovative methodological approach, based on the use of whole intact cells to monitor the effects of cell context on AApoAI variants fibrillogenic pathway, has been set up.
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Affiliation(s)
- Rosa Gaglione
- Department of Chemical Sciences, University of Naples Federico II, 80126 Naples, Italy
| | | | - Rocco Di Girolamo
- Department of Chemical Sciences, University of Naples Federico II, 80126 Naples, Italy
| | - Renata Piccoli
- Department of Chemical Sciences, University of Naples Federico II, 80126 Naples, Italy; Istituto Nazionale di Biostrutture e Biosistemi (INBB), Italy
| | - Emilia Pedone
- Istituto di Biostrutture e Bioimmagini, CNR, Naples, Italy; Research Centre on Bioactive Peptides (CIRPeB), University of Naples Federico II, Via Mezzocannone 16, 80134 Naples, Italy.
| | - Angela Arciello
- Department of Chemical Sciences, University of Naples Federico II, 80126 Naples, Italy; Istituto Nazionale di Biostrutture e Biosistemi (INBB), Italy.
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18
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Chiti F, Dobson CM. Protein Misfolding, Amyloid Formation, and Human Disease: A Summary of Progress Over the Last Decade. Annu Rev Biochem 2017; 86:27-68. [DOI: 10.1146/annurev-biochem-061516-045115] [Citation(s) in RCA: 1651] [Impact Index Per Article: 235.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023]
Abstract
Peptides and proteins have been found to possess an inherent tendency to convert from their native functional states into intractable amyloid aggregates. This phenomenon is associated with a range of increasingly common human disorders, including Alzheimer and Parkinson diseases, type II diabetes, and a number of systemic amyloidoses. In this review, we describe this field of science with particular reference to the advances that have been made over the last decade in our understanding of its fundamental nature and consequences. We list the proteins that are known to be deposited as amyloid or other types of aggregates in human tissues and the disorders with which they are associated, as well as the proteins that exploit the amyloid motif to play specific functional roles in humans. In addition, we summarize the genetic factors that have provided insight into the mechanisms of disease onset. We describe recent advances in our knowledge of the structures of amyloid fibrils and their oligomeric precursors and of the mechanisms by which they are formed and proliferate to generate cellular dysfunction. We show evidence that a complex proteostasis network actively combats protein aggregation and that such an efficient system can fail in some circumstances and give rise to disease. Finally, we anticipate the development of novel therapeutic strategies with which to prevent or treat these highly debilitating and currently incurable conditions.
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Affiliation(s)
- Fabrizio Chiti
- Department of Experimental and Clinical Biomedical Sciences “Mario Serio,” Section of Biochemistry, Università di Firenze, 50134 Firenze, Italy
| | - Christopher M. Dobson
- Department of Chemistry, Centre for Misfolding Diseases, University of Cambridge, Cambridge CB2 1EW, United Kingdom
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19
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Kimura H, Mikawa S, Mizuguchi C, Horie Y, Morita I, Oyama H, Ohgita T, Nishitsuji K, Takeuchi A, Lund-Katz S, Akaji K, Kobayashi N, Saito H. Immunochemical Approach for Monitoring of Structural Transition of ApoA-I upon HDL Formation Using Novel Monoclonal Antibodies. Sci Rep 2017; 7:2988. [PMID: 28592796 PMCID: PMC5462821 DOI: 10.1038/s41598-017-03208-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Accepted: 04/24/2017] [Indexed: 11/24/2022] Open
Abstract
Apolipoprotein A-I (apoA-I) undergoes a large conformational reorganization during remodeling of high-density lipoprotein (HDL) particles. To detect structural transition of apoA-I upon HDL formation, we developed novel monoclonal antibodies (mAbs). Splenocytes from BALB/c mice immunized with a recombinant human apoA-I, with or without conjugation with keyhole limpet hemocyanin, were fused with P3/NS1/1-Ag4-1 myeloma cells. After the HAT-selection and cloning, we established nine hybridoma clones secreting anti-apoA-I mAbs in which four mAbs recognize epitopes on the N-terminal half of apoA-I while the other five mAbs recognize the central region. ELISA and bio-layer interferometry measurements demonstrated that mAbs whose epitopes are within residues 1–43 or 44–65 obviously discriminate discoidal and spherical reconstituted HDL particles despite their great reactivities to lipid-free apoA-I and plasma HDL, suggesting the possibility of these mAbs to detect structural transition of apoA-I on HDL. Importantly, a helix-disrupting mutation of W50R into residues 44–65 restored the immunoreactivity of mAbs whose epitope being within residues 44–65 against reconstituted HDL particles, indicating that these mAbs specifically recognize the epitope region in a random coil state. These results encourage us to develop mAbs targeting epitopes in the N-terminal residues of apoA-I as useful probes for monitoring formation and remodeling of HDL particles.
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Affiliation(s)
- Hitoshi Kimura
- Department of Biophysical Chemistry, Kyoto Pharmaceutical University, 5 Nakauchi-cho, Misasagi, Yamashina-ku, Kyoto, 607-8414, Japan.,Graduate School of Pharmaceutical Sciences, Tokushima University, 1-78-1 Shomachi, Tokushima, 770-8505, Japan
| | - Shiho Mikawa
- Department of Biophysical Chemistry, Kyoto Pharmaceutical University, 5 Nakauchi-cho, Misasagi, Yamashina-ku, Kyoto, 607-8414, Japan.,Graduate School of Pharmaceutical Sciences, Tokushima University, 1-78-1 Shomachi, Tokushima, 770-8505, Japan
| | - Chiharu Mizuguchi
- Department of Biophysical Chemistry, Kyoto Pharmaceutical University, 5 Nakauchi-cho, Misasagi, Yamashina-ku, Kyoto, 607-8414, Japan.,Graduate School of Pharmaceutical Sciences, Tokushima University, 1-78-1 Shomachi, Tokushima, 770-8505, Japan
| | - Yuki Horie
- Department of Bioanalytical Chemistry, Kobe Pharmaceutical University, 4-19-1 Motoyama-Kitamachi, Higashinada-ku, Kobe, 658-8558, Japan
| | - Izumi Morita
- Department of Bioanalytical Chemistry, Kobe Pharmaceutical University, 4-19-1 Motoyama-Kitamachi, Higashinada-ku, Kobe, 658-8558, Japan
| | - Hiroyuki Oyama
- Department of Bioanalytical Chemistry, Kobe Pharmaceutical University, 4-19-1 Motoyama-Kitamachi, Higashinada-ku, Kobe, 658-8558, Japan
| | - Takashi Ohgita
- Department of Biophysical Chemistry, Kyoto Pharmaceutical University, 5 Nakauchi-cho, Misasagi, Yamashina-ku, Kyoto, 607-8414, Japan
| | - Kazuchika Nishitsuji
- Department of Molecular Pathology, Institute of Biomedical Sciences, Tokushima University Graduate School, 3-18-15 Kuramoto-cho, Tokushima, 770-8503, Japan
| | - Atsuko Takeuchi
- Analytical Laboratory, Kobe Pharmaceutical University, 4-19-1 Motoyama-Kitamachi, Higashinada-ku, Kobe, 658-8558, Japan
| | - Sissel Lund-Katz
- Lipid Research Group, Gastroenterology, Hepatology and Nutrition Division, The Children's Hospital of Philadelphia, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, 19104-4318, USA
| | - Kenichi Akaji
- Department of Medicinal Chemistry, Kyoto Pharmaceutical University, 5 Nakauchi-cho, Misasagi, Yamashina-ku, Kyoto, 607-8414, Japan
| | - Norihiro Kobayashi
- Department of Bioanalytical Chemistry, Kobe Pharmaceutical University, 4-19-1 Motoyama-Kitamachi, Higashinada-ku, Kobe, 658-8558, Japan
| | - Hiroyuki Saito
- Department of Biophysical Chemistry, Kyoto Pharmaceutical University, 5 Nakauchi-cho, Misasagi, Yamashina-ku, Kyoto, 607-8414, Japan.
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20
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Lucato CM, Lupton CJ, Halls ML, Ellisdon AM. Amyloidogenicity at a Distance: How Distal Protein Regions Modulate Aggregation in Disease. J Mol Biol 2017; 429:1289-1304. [PMID: 28342736 DOI: 10.1016/j.jmb.2017.03.021] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Revised: 03/12/2017] [Accepted: 03/14/2017] [Indexed: 12/14/2022]
Abstract
The misfolding of proteins to form amyloid is a key pathological feature of several progressive, and currently incurable, diseases. A mechanistic understanding of the pathway from soluble, native protein to insoluble amyloid is crucial for therapeutic design, and recent efforts have helped to elucidate the key molecular events that trigger protein misfolding. Generally, either global or local structural perturbations occur early in amyloidogenesis to expose aggregation-prone regions of the protein that can then self-associate to form toxic oligomers. Surprisingly, these initiating structural changes are often caused or influenced by protein regions distal to the classically amyloidogenic sequences. Understanding the importance of these distal regions in the pathogenic process has highlighted many remaining knowledge gaps regarding the precise molecular events that occur in classic aggregation pathways. In this review, we discuss how these distal regions can influence aggregation in disease and the recent technical and conceptual advances that have allowed this insight.
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Affiliation(s)
- Christina M Lucato
- Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia; Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Victoria 3800, Australia
| | - Christopher J Lupton
- Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia; Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Victoria 3800, Australia
| | - Michelle L Halls
- Drug Discovery Biology Theme, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Andrew M Ellisdon
- Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia; Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Victoria 3800, Australia.
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21
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Oda MN. Lipid-free apoA-I structure - Origins of model diversity. Biochim Biophys Acta Mol Cell Biol Lipids 2016; 1862:221-233. [PMID: 27890580 DOI: 10.1016/j.bbalip.2016.11.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Revised: 10/20/2016] [Accepted: 11/20/2016] [Indexed: 01/22/2023]
Abstract
Apolipoprotein A-I (apoA-I) is a prominent member of the exchangeable apolipoprotein class of proteins, capable of transitioning between lipid-bound and lipid-free states. It is the primary structural and functional protein of high density lipoprotein (HDL). Lipid-free apoA-I is critical to de novo HDL formation as it is the preferred substrate of the lipid transporter, ATP Binding Cassette Transporter A1 (ABCA1) Remaley et al. (2001) [1]. Lipid-free apoA-I is an important element in reverse cholesterol transport and comprehension of its structure is a core issue in our understanding of cholesterol metabolism. However, lipid-free apoA-I is highly conformationally dynamic making it a challenging subject for structural analysis. Over the past 20years there have been significant advances in overcoming the dynamic nature of lipid-free apoA-I, which have resulted in a multitude of proposed conformational models.
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Affiliation(s)
- Michael N Oda
- Children's Hospital Oakland Research Institute, Oakland, CA 94609, United States.
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22
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Arciello A, Piccoli R, Monti DM. Apolipoprotein A-I: the dual face of a protein. FEBS Lett 2016; 590:4171-4179. [DOI: 10.1002/1873-3468.12468] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Revised: 10/12/2016] [Accepted: 10/24/2016] [Indexed: 11/07/2022]
Affiliation(s)
- Angela Arciello
- Department of Chemical Sciences; University of Naples Federico II; Italy
- Istituto Nazionale di Biostrutture e Biosistemi (INBB); Rome Italy
| | - Renata Piccoli
- Department of Chemical Sciences; University of Naples Federico II; Italy
- Istituto Nazionale di Biostrutture e Biosistemi (INBB); Rome Italy
| | - Daria Maria Monti
- Department of Chemical Sciences; University of Naples Federico II; Italy
- Istituto Nazionale di Biostrutture e Biosistemi (INBB); Rome Italy
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23
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Mikawa S, Mizuguchi C, Nishitsuji K, Baba T, Shigenaga A, Shimanouchi T, Sakashita N, Otaka A, Akaji K, Saito H. Heparin promotes fibril formation by the N-terminal fragment of amyloidogenic apolipoprotein A-I. FEBS Lett 2016; 590:3492-3500. [DOI: 10.1002/1873-3468.12426] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Revised: 09/05/2016] [Accepted: 09/11/2016] [Indexed: 11/08/2022]
Affiliation(s)
- Shiho Mikawa
- Department of Biophysical Chemistry; Kyoto Pharmaceutical University; Japan
- Institute of Biomedical Sciences; Graduate School of Pharmaceutical Sciences; Tokushima University; Japan
| | - Chiharu Mizuguchi
- Department of Biophysical Chemistry; Kyoto Pharmaceutical University; Japan
- Institute of Biomedical Sciences; Graduate School of Pharmaceutical Sciences; Tokushima University; Japan
| | - Kazuchika Nishitsuji
- Department of Molecular Pathology; Institute of Biomedical Sciences; Tokushima University Graduate School; Japan
| | - Teruhiko Baba
- Biotechnology Research Institute for Drug Discovery; National Institute of Advanced Industrial Science and Technology (AIST); Tsukuba Japan
| | - Akira Shigenaga
- Institute of Biomedical Sciences; Graduate School of Pharmaceutical Sciences; Tokushima University; Japan
| | | | - Naomi Sakashita
- Department of Molecular Pathology; Institute of Biomedical Sciences; Tokushima University Graduate School; Japan
| | - Akira Otaka
- Institute of Biomedical Sciences; Graduate School of Pharmaceutical Sciences; Tokushima University; Japan
| | - Kenichi Akaji
- Department of Medicinal Chemistry; Kyoto Pharmaceutical University; Japan
| | - Hiroyuki Saito
- Department of Biophysical Chemistry; Kyoto Pharmaceutical University; Japan
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24
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Mizuguchi C, Ogata F, Mikawa S, Tsuji K, Baba T, Shigenaga A, Shimanouchi T, Okuhira K, Otaka A, Saito H. Amyloidogenic Mutation Promotes Fibril Formation of the N-terminal Apolipoprotein A-I on Lipid Membranes. J Biol Chem 2015; 290:20947-20959. [PMID: 26175149 DOI: 10.1074/jbc.m115.664227] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Indexed: 02/01/2023] Open
Abstract
The N-terminal amino acid 1-83 fragment of apolipoprotein A-I (apoA-I) has a strong propensity to form amyloid fibrils at physiological neutral pH. Because apoA-I has an ability to bind to lipid membranes, we examined the effects of the lipid environment on fibril-forming properties of the N-terminal fragment of apoA-I variants. Thioflavin T fluorescence assay as well as fluorescence and transmission microscopies revealed that upon lipid binding, fibril formation by apoA-I 1-83 is strongly inhibited, whereas the G26R mutant still retains the ability to form fibrils. Such distinct effects of lipid binding on fibril formation were also observed for the amyloidogenic prone region-containing peptides, apoA-I 8-33 and 8-33/G26R. This amyloidogenic region shifts from random coil to α-helical structure upon lipid binding. The G26R mutation appears to prevent this helix transition because lower helical propensity and more solvent-exposed conformation of the G26R variant upon lipid binding were observed in the apoA-I 1-83 fragment and 8-33 peptide. With a partially α-helical conformation induced by the presence of 2,2,2-trifluoroethanol, fibril formation by apoA-I 1-83 was strongly inhibited, whereas the G26R variant can form amyloid fibrils. These findings suggest a new possible pathway for amyloid fibril formation by the N-terminal fragment of apoA-I variants: the amyloidogenic mutations partially destabilize the α-helical structure formed upon association with lipid membranes, resulting in physiologically relevant conformations that allow fibril formation.
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Affiliation(s)
- Chiharu Mizuguchi
- Institute of Biomedical Sciences, Graduate School of Pharmaceutical Sciences, Tokushima University, 1-78-1 Shomachi, Tokushima 770-8505, Japan
| | - Fuka Ogata
- Institute of Biomedical Sciences, Graduate School of Pharmaceutical Sciences, Tokushima University, 1-78-1 Shomachi, Tokushima 770-8505, Japan
| | - Shiho Mikawa
- Institute of Biomedical Sciences, Graduate School of Pharmaceutical Sciences, Tokushima University, 1-78-1 Shomachi, Tokushima 770-8505, Japan
| | - Kohei Tsuji
- Institute of Biomedical Sciences, Graduate School of Pharmaceutical Sciences, Tokushima University, 1-78-1 Shomachi, Tokushima 770-8505, Japan
| | - Teruhiko Baba
- Research Center for Stem Cell Engineering (SCRC), National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8565, Japan
| | - Akira Shigenaga
- Institute of Biomedical Sciences, Graduate School of Pharmaceutical Sciences, Tokushima University, 1-78-1 Shomachi, Tokushima 770-8505, Japan
| | - Toshinori Shimanouchi
- Graduate School of Environmental and Life Science, Okayama University, Okayama 700-8530, Japan
| | - Keiichiro Okuhira
- Institute of Biomedical Sciences, Graduate School of Pharmaceutical Sciences, Tokushima University, 1-78-1 Shomachi, Tokushima 770-8505, Japan
| | - Akira Otaka
- Institute of Biomedical Sciences, Graduate School of Pharmaceutical Sciences, Tokushima University, 1-78-1 Shomachi, Tokushima 770-8505, Japan
| | - Hiroyuki Saito
- Institute of Biomedical Sciences, Graduate School of Pharmaceutical Sciences, Tokushima University, 1-78-1 Shomachi, Tokushima 770-8505, Japan.
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25
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Louros NN, Tsiolaki PL, Griffin MDW, Howlett GJ, Hamodrakas SJ, Iconomidou VA. Chameleon 'aggregation-prone' segments of apoA-I: A model of amyloid fibrils formed in apoA-I amyloidosis. Int J Biol Macromol 2015; 79:711-8. [PMID: 26049118 DOI: 10.1016/j.ijbiomac.2015.05.032] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Revised: 05/20/2015] [Accepted: 05/22/2015] [Indexed: 11/18/2022]
Abstract
Apolipoprotein A-I (apoA-I) is the major component of high density lipoproteins and plays a vital role in reverse cholesterol transport. Lipid-free apoA-I is the main constituent of amyloid deposits found in atherosclerotic plaques, an acquired type of amyloidosis, whereas its N-terminal fragments have been associated with a hereditary form, known as familial apoA-I amyloidosis. Here, we identified and verified four "aggregation-prone" segments of apoA-I with amyloidogenic properties, utilizing electron microscopy, X-ray fiber diffraction, ATR FT-IR spectroscopy and polarized light microscopy. These segments may act as conformational switches, possibly controlling the transition of the α-helical apoA-I content into the "cross-β" architecture of amyloid fibrils. A structural model illuminating the structure of amyloid fibrils formed by the N-terminal fragments of apoA-I is proposed, indicating that two of the identified chameleon segments may play a vital part in the formation of amyloid fibrils in familial apoA-I amyloidosis.
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Affiliation(s)
- Nikolaos N Louros
- Department of Cell Biology and Biophysics, Faculty of Biology, University of Athens, Panepistimiopolis, Athens 157 01, Greece
| | - Paraskevi L Tsiolaki
- Department of Cell Biology and Biophysics, Faculty of Biology, University of Athens, Panepistimiopolis, Athens 157 01, Greece
| | - Michael D W Griffin
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, VIC 3010, Australia
| | - Geoffrey J Howlett
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, VIC 3010, Australia
| | - Stavros J Hamodrakas
- Department of Cell Biology and Biophysics, Faculty of Biology, University of Athens, Panepistimiopolis, Athens 157 01, Greece
| | - Vassiliki A Iconomidou
- Department of Cell Biology and Biophysics, Faculty of Biology, University of Athens, Panepistimiopolis, Athens 157 01, Greece.
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26
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Rosú SA, Rimoldi OJ, Prieto ED, Curto LM, Delfino JM, Ramella NA, Tricerri MA. Amyloidogenic propensity of a natural variant of human apolipoprotein A-I: stability and interaction with ligands. PLoS One 2015; 10:e0124946. [PMID: 25950566 PMCID: PMC4423886 DOI: 10.1371/journal.pone.0124946] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2015] [Accepted: 03/19/2015] [Indexed: 12/18/2022] Open
Abstract
A number of naturally occurring mutations of human apolipoprotein A-I (apoA-I) have been associated with hereditary amyloidoses. The molecular mechanisms involved in amyloid-associated pathology remain largely unknown. Here we examined the effects of the Arg173Pro point mutation in apoA-I on the structure, stability, and aggregation propensity, as well as on the ability to bind to putative ligands. Our results indicate that the mutation induces a drastic loss of stability, and a lower efficiency to bind to phospholipid vesicles at physiological pH, which could determine the observed higher tendency to aggregate as pro-amyloidogenic complexes. Incubation under acidic conditions does not seem to induce significant desestabilization or aggregation tendency, neither does it contribute to the binding of the mutant to sodium dodecyl sulfate. While the binding to this detergent is higher for the mutant as compared to wt apoA-I, the interaction of the Arg173Pro variant with heparin depends on pH, being lower at pH 5.0 and higher than wt under physiological pH conditions. We suggest that binding to ligands as heparin or other glycosaminoglycans could be key events tuning the fine details of the interaction of apoA-I variants with the micro-environment, and probably eliciting the toxicity of these variants in hereditary amyloidoses.
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Affiliation(s)
- Silvana A. Rosú
- Instituto de Investigaciones Bioquímicas de La Plata (INIBIOLP), CONICET, La Plata, Buenos Aires, Argentina
- Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Buenos Aires, Argentina
| | - Omar J. Rimoldi
- Instituto de Investigaciones Bioquímicas de La Plata (INIBIOLP), CONICET, La Plata, Buenos Aires, Argentina
- Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Buenos Aires, Argentina
| | - Eduardo D. Prieto
- Instituto de Investigaciones Bioquímicas de La Plata (INIBIOLP), CONICET, La Plata, Buenos Aires, Argentina
- Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas (INIFTA), Universidad Nacional de La Plata-CONICET, La Plata, Buenos Aires, Argentina
| | - Lucrecia M. Curto
- Departamento de Química Biológica e Instituto de Bioquímica y Biofísica, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - José M. Delfino
- Departamento de Química Biológica e Instituto de Bioquímica y Biofísica, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Nahuel A. Ramella
- Instituto de Investigaciones Bioquímicas de La Plata (INIBIOLP), CONICET, La Plata, Buenos Aires, Argentina
- Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Buenos Aires, Argentina
| | - M. Alejandra Tricerri
- Instituto de Investigaciones Bioquímicas de La Plata (INIBIOLP), CONICET, La Plata, Buenos Aires, Argentina
- Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Buenos Aires, Argentina
- * E-mail:
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27
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Chan GKL, Witkowski A, Gantz DL, Zhang TO, Zanni MT, Jayaraman S, Cavigiolio G. Myeloperoxidase-mediated Methionine Oxidation Promotes an Amyloidogenic Outcome for Apolipoprotein A-I. J Biol Chem 2015; 290:10958-71. [PMID: 25759391 DOI: 10.1074/jbc.m114.630442] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2014] [Indexed: 11/06/2022] Open
Abstract
High plasma levels of apolipoprotein A-I (apoA-I) correlate with cardiovascular health, whereas dysfunctional apoA-I is a cause of atherosclerosis. In the atherosclerotic plaques, amyloid deposition increases with aging. Notably, apoA-I is the main component of these amyloids. Recent studies identified high levels of oxidized lipid-free apoA-I in atherosclerotic plaques. Likely, myeloperoxidase (MPO) secreted by activated macrophages in atherosclerotic lesions is the promoter of such apoA-I oxidation. We hypothesized that apoA-I oxidation by MPO levels similar to those present in the artery walls in atherosclerosis can promote apoA-I structural changes and amyloid fibril formation. ApoA-I was exposed to exhaustive chemical (H2O2) oxidation or physiological levels of enzymatic (MPO) oxidation and incubated at 37 °C and pH 6.0 to induce fibril formation. Both chemically and enzymatically oxidized apoA-I produced fibrillar amyloids after a few hours of incubation. The amyloid fibrils were composed of full-length apoA-I with differential oxidation of the three methionines. Met to Leu apoA-I variants were used to establish the predominant role of oxidation of Met-86 and Met-148 in the fibril formation process. Importantly, a small amount of preformed apoA-I fibrils was able to seed amyloid formation in oxidized apoA-I at pH 7.0. In contrast to hereditary amyloidosis, wherein specific mutations of apoA-I cause protein destabilization and amyloid deposition, oxidative conditions similar to those promoted by local inflammation in atherosclerosis are sufficient to transform full-length wild-type apoA-I into an amyloidogenic protein. Thus, MPO-mediated oxidation may be implicated in the mechanism that leads to amyloid deposition in the atherosclerotic plaques in vivo.
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Affiliation(s)
- Gary K L Chan
- From the Children's Hospital Oakland Research Institute, Oakland, California 94609
| | - Andrzej Witkowski
- From the Children's Hospital Oakland Research Institute, Oakland, California 94609
| | - Donald L Gantz
- Department of Physiology and Biophysics, Boston University School of Medicine, Boston, Massachusetts 02118, and
| | - Tianqi O Zhang
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706
| | - Martin T Zanni
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706
| | - Shobini Jayaraman
- Department of Physiology and Biophysics, Boston University School of Medicine, Boston, Massachusetts 02118, and
| | - Giorgio Cavigiolio
- From the Children's Hospital Oakland Research Institute, Oakland, California 94609,
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28
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Mead S, Reilly MM. A new prion disease: relationship with central and peripheral amyloidoses. Nat Rev Neurol 2015; 11:90-7. [DOI: 10.1038/nrneurol.2014.263] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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29
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Pey AL, Maggi M, Valentini G. Insights into human phosphoglycerate kinase 1 deficiency as a conformational disease from biochemical, biophysical, and in vitro expression analyses. J Inherit Metab Dis 2014; 37:909-16. [PMID: 24838780 DOI: 10.1007/s10545-014-9721-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2014] [Revised: 04/17/2014] [Accepted: 04/22/2014] [Indexed: 12/14/2022]
Abstract
Mutations in genes encoding metabolic enzymes are often the cause of inherited diseases. Mutations usually affect the ability of proteins to fold properly, thus leading to enzyme loss of function. In this work, we explored the relationships between protein stability, aggregation, and degradation in vitro and inside cells in a large set of mutants associated with human phosphoglycerate kinase 1 (hPGK1) deficiency. To this end, we studied a third of the pathogenic alleles reported in the literature using expression analyses and biochemical, biophysical, and computational procedures. Our results show that most pathogenic variants studied had an increased tendency to aggregate when expressed in Escherichia coli, well correlating with the denaturation half-lives measured by thermal denaturation in vitro. Further, the most deleterious mutants show reduced stability toward chemical denaturation and proteolysis, supporting a pivotal role of thermodynamic stability in the propensity toward aggregation and proteolysis of pathogenic hPGK1 mutants in vitro and inside cells. Our strategy allowed us to unravel the complex relationships between protein stability, aggregation, and degradation in hPGK1 deficiency, which might be used to understand disease mechanisms in many inborn errors of metabolism. Our results suggest that pharmacological chaperones and protein homeostasis modulators could be considered as good candidates for therapeutic approaches for hPGK1 deficiency.
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Affiliation(s)
- Angel L Pey
- Department of Physical Chemistry, University of Granada, Granada, Spain,
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30
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Petrlova J, Bhattacherjee A, Boomsma W, Wallin S, Lagerstedt JO, Irbäck A. Conformational and aggregation properties of the 1-93 fragment of apolipoprotein A-I. Protein Sci 2014; 23:1559-71. [PMID: 25131953 DOI: 10.1002/pro.2534] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Revised: 07/11/2014] [Accepted: 08/04/2014] [Indexed: 11/12/2022]
Abstract
Several disease-linked mutations of apolipoprotein A-I, the major protein in high-density lipoprotein (HDL), are known to be amyloidogenic, and the fibrils often contain N-terminal fragments of the protein. Here, we present a combined computational and experimental study of the fibril-associated disordered 1-93 fragment of this protein, in wild-type and mutated (G26R, S36A, K40L, W50R) forms. In atomic-level Monte Carlo simulations of the free monomer, validated by circular dichroism spectroscopy, we observe changes in the position-dependent β-strand probability induced by mutations. We find that these conformational shifts match well with the effects of these mutations in thioflavin T fluorescence and transmission electron microscopy experiments. Together, our results point to molecular mechanisms that may have a key role in disease-linked aggregation of apolipoprotein A-I.
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Affiliation(s)
- Jitka Petrlova
- Department of Experimental Medical Science, Lund University, BMC Floor C12, SE-221 84, Lund, Sweden
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31
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Das M, Mei X, Jayaraman S, Atkinson D, Gursky O. Amyloidogenic mutations in human apolipoprotein A-I are not necessarily destabilizing - a common mechanism of apolipoprotein A-I misfolding in familial amyloidosis and atherosclerosis. FEBS J 2014; 281:2525-42. [PMID: 24702826 DOI: 10.1111/febs.12809] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Revised: 03/19/2014] [Accepted: 04/04/2014] [Indexed: 12/18/2022]
Abstract
High-density lipoproteins and their major protein, apolipoprotein A-I (apoA-I), remove excess cellular cholesterol and protect against atherosclerosis. However, in acquired amyloidosis, nonvariant full-length apoA-I deposits as fibrils in atherosclerotic plaques; in familial amyloidosis, N-terminal fragments of variant apoA-I deposit in vital organs, damaging them. Recently, we used the crystal structure of Δ(185-243)apoA-I to show that amyloidogenic mutations destabilize apoA-I and increase solvent exposure of the extended strand 44-55 that initiates β-aggregation. In the present study, we test this hypothesis by exploring naturally occurring human amyloidogenic mutations, W50R and G26R, within or close to this strand. The mutations caused small changes in the protein's α-helical content, stability, proteolytic pattern and protein-lipid interactions. These changes alone were unlikely to account for amyloidosis, suggesting the importance of other factors. Sequence analysis predicted several amyloid-prone segments that can initiate apoA-I misfolding. Aggregation studies using N-terminal fragments verified this prediction experimentally. Three predicted N-terminal amyloid-prone segments, mapped on the crystal structure, formed an α-helical cluster. Structural analysis indicates that amyloidogenic mutations or Met86 oxidation perturb native packing in this cluster. Taken together, the results suggest that structural perturbations in the amyloid-prone segments trigger α-helix to β-sheet conversion in the N-terminal ~ 75 residues forming the amyloid core. Polypeptide outside this core can be proteolysed to form 9-11 kDa N-terminal fragments found in familial amyloidosis. Our results imply that apoA-I misfolding in familial and acquired amyloidosis follows a similar mechanism that does not require significant structural destabilization or proteolysis. This novel mechanism suggests potential therapeutic interventions for apoA-I amyloidosis.
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Affiliation(s)
- Madhurima Das
- Department of Physiology and Biophysics, Boston University School of Medicine, Boston, MA, USA
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32
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Adachi E, Kosaka A, Tsuji K, Mizuguchi C, Kawashima H, Shigenaga A, Nagao K, Akaji K, Otaka A, Saito H. The extreme N-terminal region of human apolipoprotein A-I has a strong propensity to form amyloid fibrils. FEBS Lett 2013; 588:389-94. [PMID: 24316228 DOI: 10.1016/j.febslet.2013.11.031] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2013] [Revised: 11/10/2013] [Accepted: 11/25/2013] [Indexed: 02/04/2023]
Abstract
The N-terminal 1-83 residues of apolipoprotein A-I (apoA-I) have a strong propensity to form amyloid fibrils, in which the 46-59 segment was reported to aggregate to form amyloid-like fibrils. In this study, we demonstrated that a fragment peptide comprising the extreme N-terminal 1-43 residues strongly forms amyloid fibrils with a transition to β-sheet-rich structure, and that the G26R point mutation enhances the fibril formation of this segment. Our results suggest that in addition to the 46-59 segment, the extreme N-terminal region plays a crucial role in the development of amyloid fibrils by the N-terminal fragment of amyloidogenic apoA-I variants.
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Affiliation(s)
- Emi Adachi
- Institute of Health Biosciences and Graduate School of Pharmaceutical Sciences, The University of Tokushima, 1-78-1 Shomachi, Tokushima 770-8505, Japan
| | - Asako Kosaka
- Institute of Health Biosciences and Graduate School of Pharmaceutical Sciences, The University of Tokushima, 1-78-1 Shomachi, Tokushima 770-8505, Japan
| | - Kohei Tsuji
- Institute of Health Biosciences and Graduate School of Pharmaceutical Sciences, The University of Tokushima, 1-78-1 Shomachi, Tokushima 770-8505, Japan
| | - Chiharu Mizuguchi
- Institute of Health Biosciences and Graduate School of Pharmaceutical Sciences, The University of Tokushima, 1-78-1 Shomachi, Tokushima 770-8505, Japan
| | - Hiroyuki Kawashima
- Department of Medicinal Chemistry, Kyoto Pharmaceutical University, Yamashina-ku, Kyoto 607-8412, Japan
| | - Akira Shigenaga
- Institute of Health Biosciences and Graduate School of Pharmaceutical Sciences, The University of Tokushima, 1-78-1 Shomachi, Tokushima 770-8505, Japan
| | - Kohjiro Nagao
- Institute of Health Biosciences and Graduate School of Pharmaceutical Sciences, The University of Tokushima, 1-78-1 Shomachi, Tokushima 770-8505, Japan
| | - Kenichi Akaji
- Department of Medicinal Chemistry, Kyoto Pharmaceutical University, Yamashina-ku, Kyoto 607-8412, Japan
| | - Akira Otaka
- Institute of Health Biosciences and Graduate School of Pharmaceutical Sciences, The University of Tokushima, 1-78-1 Shomachi, Tokushima 770-8505, Japan
| | - Hiroyuki Saito
- Institute of Health Biosciences and Graduate School of Pharmaceutical Sciences, The University of Tokushima, 1-78-1 Shomachi, Tokushima 770-8505, Japan.
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33
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Mutation mapping of apolipoprotein A-I structure assisted with the putative cholesterol recognition regions. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2013; 1834:2030-5. [DOI: 10.1016/j.bbapap.2013.06.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2013] [Revised: 06/04/2013] [Accepted: 06/15/2013] [Indexed: 12/22/2022]
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34
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Kato Y, Yagi H, Kaji Y, Oshika T, Goto Y. Benzalkonium chloride accelerates the formation of the amyloid fibrils of corneal dystrophy-associated peptides. J Biol Chem 2013; 288:25109-25118. [PMID: 23861389 DOI: 10.1074/jbc.m113.477695] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Corneal dystrophies are genetic disorders resulting in progressive corneal clouding due to the deposition of amyloid fibrils derived from keratoepithelin, also called transforming growth factor β-induced protein (TGFBI). The formation of amyloid fibrils is often accelerated by surfactants such as sodium dodecyl sulfate (SDS). Most eye drops contain benzalkonium chloride (BAC), a cationic surfactant, as a preservative substance. In the present study, we aimed to reveal the role of BAC in the amyloid fibrillation of keratoepithelin-derived peptides in vitro. We used three types of 22-residue synthetic peptides covering Leu110-Glu131 of the keratoepithelin sequence: an R-type peptide with wild-type R124, a C-type peptide with C124 associated with lattice corneal dystrophy type I, and a H-type peptide with H124 associated with granular corneal dystrophy type II. The time courses of spontaneous amyloid fibrillation and seed-dependent fibril elongation were monitored in the presence of various concentrations of BAC or SDS using thioflavin T fluorescence. BAC and SDS accelerated the fibrillation of all synthetic peptides in the absence and presence of seeds. Optimal acceleration occurred near the CMC, which suggests that the unstable and dynamic interactions of keratoepithelin peptides with amphipathic surfactants led to the formation of fibrils. These results suggest that eye drops containing BAC may deteriorate corneal dystrophies and that those without BAC are preferred especially for patients with corneal dystrophies.
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Affiliation(s)
- Yusuke Kato
- From the Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan and
| | - Hisashi Yagi
- From the Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan and
| | - Yuichi Kaji
- the Department of Ophthalmology, Institute of Clinical Medicine, University of Tsukuba, Tennoudai 1-1-1, Tsukuba, Ibaraki 305-8575, Japan
| | - Tetsuro Oshika
- the Department of Ophthalmology, Institute of Clinical Medicine, University of Tsukuba, Tennoudai 1-1-1, Tsukuba, Ibaraki 305-8575, Japan
| | - Yuji Goto
- From the Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan and.
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35
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Adachi E, Nakajima H, Mizuguchi C, Dhanasekaran P, Kawashima H, Nagao K, Akaji K, Lund-Katz S, Phillips MC, Saito H. Dual role of an N-terminal amyloidogenic mutation in apolipoprotein A-I: destabilization of helix bundle and enhancement of fibril formation. J Biol Chem 2012; 288:2848-56. [PMID: 23233678 DOI: 10.1074/jbc.m112.428052] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
A number of naturally occurring mutations of apolipoprotein (apo) A-I, the major protein of HDL, are known to be associated with hereditary amyloidosis and atherosclerosis. Here, we examined the effects of the G26R point mutation in apoA-I (apoA-I(Iowa)) on the structure, stability, and aggregation propensity to form amyloid fibril of full-length apoA-I and the N-terminal fragment of apoA-I. Circular dichroism and fluorescence measurements demonstrated that the G26R mutation destabilizes the N-terminal helix bundle domain of full-length protein, leading to increased hydrophobic surface exposure, whereas it has no effect on the initial structure of the N-terminal 1-83 fragment, which is predominantly a random coil structure. Upon incubation for extended periods at neutral pH, the N-terminal 1-83 variants undergo a conformational change to β-sheet-rich structure with a great increase in thioflavin T fluorescence, whereas no structural change is observed in full-length proteins. Comparison of fibril-forming propensity among substituted mutants at Gly-26 position of 1-83 fragments demonstrated that the G26R mutation enhances the nucleation step of fibril formation, whereas G26K and G26E mutations have small or inhibiting effects on the formation of fibrils. These fibrils of the 1-83 variants have long and straight morphology as revealed by atomic force microscopy and exhibited significant toxicity with HEK293 cells. Our results indicate dual critical roles of the arginine residue at position 26 in apoA-I(Iowa): destabilization of the N-terminal helix bundle structure in full-length protein and enhancement of amyloid fibril formation by the N-terminal 1-83 fragment.
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Affiliation(s)
- Emi Adachi
- Institute of Health Biosciences and Graduate School of Pharmaceutical Sciences, The University of Tokushima, 1-78-1 Shomachi, Tokushima 770-8505, Japan
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36
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Arciello A, De Marco N, Del Giudice R, Guglielmi F, Pucci P, Relini A, Monti DM, Piccoli R. Insights into the fate of the N-terminal amyloidogenic polypeptide of ApoA-I in cultured target cells. J Cell Mol Med 2012; 15:2652-63. [PMID: 21306558 PMCID: PMC4373434 DOI: 10.1111/j.1582-4934.2011.01271.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Apolipoprotein A-I (ApoA-I) is an extracellular lipid acceptor, whose role in cholesterol efflux and high-density lipoprotein formation is mediated by ATP-binding cassette transporter A1 (ABCA1). Nevertheless, some ApoA-I variants are associated to systemic forms of amyloidosis, characterized by extracellular fibril deposition in peripheral organs. Heart amyloid fibrils were found to be mainly constituted by the 93-residue N-terminal fragment of ApoA-I, named [1-93]ApoA-I. In this paper, rat cardiomyoblasts were used as target cells to analyse binding, internalization and intracellular fate of the fibrillogenic polypeptide in comparison to full-length ApoA-I. We provide evidence that the polypeptide: (i) binds to specific sites on cell membrane (K(d) = 5.90 ± 0.70 × 10(-7) M), where it partially co-localizes with ABCA1, as also described for ApoA-I; (ii) is internalized mostly by chlatrin-mediated endocytosis and lipid rafts, whereas ApoA-I is internalized preferentially by chlatrin-coated pits and macropinocytosis and (iii) is rapidly degraded by proteasome and lysosomes, whereas ApoA-I partially co-localizes with recycling endosomes. Vice versa, amyloid fibrils, obtained by in vitro aggregation of [1-93]ApoA-I, were found to be unable to enter the cells. We propose that internalization and intracellular degradation of [1-93]ApoA-I may divert the polypeptide from amyloid fibril formation and contribute to the slow progression and late onset that characterize this pathology.
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Affiliation(s)
- Angela Arciello
- Department of Structural and Functional Biology, University of Naples Federico II, School of Biotechnological Sciences, Naples, Italy
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37
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Monti DM, Di Gaetano S, Del Giudice R, Giangrande C, Amoresano A, Monti M, Arciello A, Piccoli R. Apolipoprotein A-I amyloidogenic variant L174S, expressed and isolated from stably transfected mammalian cells, is associated with fatty acids. Amyloid 2012; 19:21-7. [PMID: 22295944 DOI: 10.3109/13506129.2011.651544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Sixteen variants of apolipoprotein A-I (ApoA-I) are associated with hereditary systemic amyloidoses, characterized by amyloid deposition in peripheral organs of patients. As these are heterozygous for the amyloidogenic variants, their isolation from plasma is impracticable and recombinant expression systems are needed. Here we report the expression of recombinant ApoA-I amyloidogenic variant Leu174 with Ser (L174S) in stably transfected Chinese hamster ovary-K1 cells. ApoA-I variant L174S was found to be efficiently secreted in the culture medium, from which it was isolated following a one-step purification procedure. Mass spectrometry analyses allowed the qualitative and quantitative definition of the amyloidogenic variant lipid content, which was found to consist of two saturated and two monounsaturated fatty acids. Interestingly, the same lipid species were found to be associated with the wild-type ApoA-I, expressed and isolated using the same cell system, with lower values of the lipid to protein molar ratios with respect to the amyloidogenic variant. A possible role of fatty acids in trafficking and secretion of apolipoproteins may be hypothesized.
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Affiliation(s)
- Daria Maria Monti
- Department of Structural and Functional Biology, University of Naples Federico II, School of Biotechnological Sciences, Naples, Italy
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38
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Abstract
Familial amyloid polyneuropathies (FAPs) are a group of life-threatening multisystem disorders transmitted as an autosomal dominant trait. Nerve lesions are induced by deposits of amyloid fibrils, most commonly due to mutated transthyretin (TTR). Less often the precursor of amyloidosis is mutant apolipoprotein A-1 or gelsolin. The first identified cause of FAP-the TTR Val30Met mutation-is still the most common of more than 100 amyloidogenic point mutations identified worldwide. The penetrance and age at onset of FAP among people carrying the same mutation vary between countries. The symptomatology and clinical course of FAP can be highly variable. TTR FAP typically causes a nerve length-dependent polyneuropathy that starts in the feet with loss of temperature and pain sensations, along with life-threatening autonomic dysfunction leading to cachexia and death within 10 years on average. TTR is synthesised mainly in the liver, and liver transplantation seems to have a favourable effect on the course of neuropathy, but not on cardiac or eye lesions. Oral administration of tafamidis meglumine, which prevents misfolding and deposition of mutated TTR, is under evaluation in patients with TTR FAP. In future, patients with FAP might benefit from gene therapy; however, genetic counselling is recommended for the prevention of all types of FAP.
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Gursky O, Mei X, Atkinson D. The crystal structure of the C-terminal truncated apolipoprotein A-I sheds new light on amyloid formation by the N-terminal fragment. Biochemistry 2011; 51:10-8. [PMID: 22229410 DOI: 10.1021/bi2017014] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Apolipoprotein A-I (apoA-I) is the main protein of plasma high-density lipoproteins (HDL, or good cholesterol) that remove excess cell cholesterol and protect against atherosclerosis. In hereditary amyloidosis, mutations in apoA-I promote its proteolysis and the deposition of the 9-11 kDa N-terminal fragments as fibrils in vital organs such as kidney, liver, and heart, causing organ damage. All known amyloidogenic mutations in human apoA-I are clustered in two residue segments, 26-107 and 154-178. The X-ray crystal structure of the C-terminal truncated human protein, Δ(185-243)apoA-I, determined to 2.2 Å resolution by Mei and Atkinson, provides the structural basis for understanding apoA-I destabilization in amyloidosis. The sites of amyloidogenic mutations correspond to key positions within the largely helical four-segment bundle comprised of residues 1-120 and 144-184. Mutations in these positions disrupt the bundle structure and destabilize lipid-free apoA-I, thereby promoting its proteolysis. Moreover, many mutations place a hydrophilic or Pro group in the middle of the hydrophobic lipid-binding face of the amphipathic α-helices, which will likely shift the population distribution from HDL-bound to lipid-poor/free apoA-I that is relatively unstable and labile to proteolysis. Notably, the crystal structure shows segment L44-S55 in an extended conformation consistent with the β-strand-like geometry. Exposure of this segment upon destabilization of the four-segment bundle probably initiates the α-helix to β-sheet conversion in amyloidosis. In summary, we propose that the amyloidogenic mutations promote apoA-I proteolysis by destabilizing the protein structure not only in the lipid-free but also in the HDL-bound form, with segment L44-S55 providing a likely template for the cross-β-sheet conformation.
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Affiliation(s)
- Olga Gursky
- Department of Physiology and Biophysics, Boston University School of Medicine, Boston, Massachusetts 02118, United States.
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Yanagi K, Ashizaki M, Yagi H, Sakurai K, Lee YH, Goto Y. Hexafluoroisopropanol induces amyloid fibrils of islet amyloid polypeptide by enhancing both hydrophobic and electrostatic interactions. J Biol Chem 2011; 286:23959-66. [PMID: 21566116 PMCID: PMC3129177 DOI: 10.1074/jbc.m111.226688] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2011] [Revised: 04/28/2011] [Indexed: 12/31/2022] Open
Abstract
Although amyloid fibrils deposit with various proteins, the comprehensive mechanism by which they form remains unclear. We studied the formation of fibrils of human islet amyloid polypeptide associated with type II diabetes in the presence of various concentrations of 1,1,1,3,3,3-hexafluoroisopropanol (HFIP) under acidic and neutral pH conditions using CD, amyloid-specific thioflavin T fluorescence, fluorescence imaging with thioflavin T, and atomic force microscopy. At low pH, the formation of fibrils was promoted by HFIP with an optimum at 5% (v/v). At neutral pH in the absence of HFIP, significant amounts of amorphous aggregates formed in addition to the fibrils. The addition of HFIP suppressed the formation of amorphous aggregates, leading to a predominance of fibrils with an optimum effect at 25% (v/v). Under both conditions, higher concentrations of HFIP dissolved the fibrils and stabilized the α-helical structure. The results indicate that fibrils and amorphous aggregates are different types of precipitates formed by exclusion from water-HFIP mixtures. The exclusion occurs through the combined effects of hydrophobic interactions and electrostatic interactions, both of which are strengthened by low concentrations of HFIP, and a subtle balance between the two types of interactions determines whether the fibrils or amorphous aggregates dominate. We suggest a general view of how the structure of precipitates varies dramatically from single crystals to amyloid fibrils and amorphous aggregates.
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Affiliation(s)
- Kotaro Yanagi
- From the Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan
| | - Mizue Ashizaki
- From the Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan
| | - Hisashi Yagi
- From the Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan
| | - Kazumasa Sakurai
- From the Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan
| | - Young-Ho Lee
- From the Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan
| | - Yuji Goto
- From the Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan
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