1
|
Goto Y, Nakajima K, Yamamoto S, Yamaguchi K. Supersaturation, a Critical Factor Underlying Proteostasis of Amyloid Fibril Formation. J Mol Biol 2024; 436:168475. [PMID: 38311232 DOI: 10.1016/j.jmb.2024.168475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Revised: 01/29/2024] [Accepted: 01/31/2024] [Indexed: 02/10/2024]
Abstract
From a physicochemical viewpoint, amyloid fibril formation is a phase transition from soluble to crystal-like sates limited by supersaturation. It occurs only above solubility (i.e., the solubility limit) coupled with a breakdown of supersaturation. Although many studies have examined the role of molecular chaperones in the context of proteostasis, the role of supersaturation has not been addressed. Moreover, although molecular chaperone-dependent disaggregations have been reported for preformed amyloid fibrils, amyloid fibrils will not dissolve above the solubility of monomers, even if agitations fragment long fibrils to shorter amyloid particles. On the other hand, on considering a reversible and coupled equilibrium of interactions, folding/unfolding and amyloid formation/disaggregation, molecules stabilizing native states can work as a disaggregase reversing the amyloid fibrils to monomers. It is likely that the proteostasis network has various intra- and extracellular components which disaggregate preformed amyloid fibrils as well as prevent amyloid formation. Further studies with a view of solubility and supersaturation will be essential for comprehensive understanding of proteostasis.
Collapse
Affiliation(s)
- Yuji Goto
- Microsonochemistry Joint Research Chair, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan.
| | - Kichitaro Nakajima
- Microsonochemistry Joint Research Chair, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Suguru Yamamoto
- Division of Clinical Nephrology and Rheumatology, Graduate School of Medical and Dental Sciences, Niigata University, Niigata 951-8510, Japan
| | - Keiichi Yamaguchi
- Microsonochemistry Joint Research Chair, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
| |
Collapse
|
2
|
Nakajima K, Ota T, Toda H, Yamaguchi K, Goto Y, Ogi H. Surface Modification of Ultrasonic Cavitation by Surfactants Improves Detection Sensitivity of α-Synuclein Amyloid Seeds. ACS Chem Neurosci 2024; 15:1643-1651. [PMID: 38546732 DOI: 10.1021/acschemneuro.4c00071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/18/2024] Open
Abstract
The rapid amplification and sensitive detection of α-synuclein (αSyn) seeds is an efficient approach for the early diagnosis of Parkinson's disease. Ultrasonication stands out as a promising method for the rapid amplification of αSyn seeds because of its robust fibril fragmentation capability. However, ultrasonication also induces the primary nucleation of αSyn monomers, deteriorating the seed detection sensitivity by generating seed-independent fibrils. In this study, we show that an addition of surfactants to the αSyn monomer solution during αSyn seed detection under ultrasonication remarkably improves the detection sensitivity of the αSyn seeds by a factor of 100-1000. Chemical kinetic analysis reveals that these surfactants reduce the rate of primary nucleation while promoting the fragmentation of the αSyn fibrils under ultrasonication. These effects are attributed to the modification of the ultrasonic cavitation surface by the surfactants. Our study enhances the utility of ultrasonication in clinical assays targeting αSyn seeds as the Parkinson's disease biomarker.
Collapse
Affiliation(s)
- Kichitaro Nakajima
- Graduate School of Engineering, Osaka University, Yamadaoka 2-2, Suita, Osaka 565-0871, Japan
| | - Tomoki Ota
- Graduate School of Engineering, Osaka University, Yamadaoka 2-2, Suita, Osaka 565-0871, Japan
| | - Hajime Toda
- Graduate School of Engineering, Osaka University, Yamadaoka 2-2, Suita, Osaka 565-0871, Japan
| | - Keiichi Yamaguchi
- Graduate School of Engineering, Osaka University, Yamadaoka 2-2, Suita, Osaka 565-0871, Japan
| | - Yuji Goto
- Graduate School of Engineering, Osaka University, Yamadaoka 2-2, Suita, Osaka 565-0871, Japan
| | - Hirotsugu Ogi
- Graduate School of Engineering, Osaka University, Yamadaoka 2-2, Suita, Osaka 565-0871, Japan
| |
Collapse
|
3
|
Lordifard P, Shariatpanahi SP, Khajeh K, Saboury AA, Goliaei B. Frequency dependence of ultrasonic effects on the kinetics of hen egg white lysozyme fibrillation. Int J Biol Macromol 2024; 254:127871. [PMID: 37952804 DOI: 10.1016/j.ijbiomac.2023.127871] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2023] [Revised: 10/23/2023] [Accepted: 11/01/2023] [Indexed: 11/14/2023]
Abstract
Our study aimed to investigate the effects of ultrasound on the fibrillation kinetics of HEWL (hen egg white lysozyme) and its physicochemical properties. Ultrasound, a mechanical wave, can induce conformational changes in proteins. To achieve this, we developed an ultrasound exposure system and used various biophysical techniques, including ThT fluorescence spectroscopy, ATR-FTIR, Far-UV CD spectrophotometry, Fluorescence microscopy, UV-spectroscopy, and seeding experiments. Our results revealed that higher frequencies significantly accelerated the fibrillation of lysozyme by unfolding the native protein and promoting the fibrillation process, thereby reducing the lag time. We observed a change in the secondary structure of the sonicated protein change to the β-structure, but there was no difference in the Tm of native and sonicated proteins. Furthermore, we found that higher ultrasound frequencies had a greater seeding effect. We propose that the effect of frequency can be explained by the impact of the Reynolds number, and for the Megahertz frequency range, we are almost at the transition regime of turbulence. Our results suggest that laminar flows may not induce any significant change in the fibrillation kinetics, while turbulent flows may affect the process.
Collapse
Affiliation(s)
- Parinaz Lordifard
- Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran.
| | | | - Khosro Khajeh
- Department of Biochemistry, Faculty of Biological Science, Tarbiat Modares University, Tehran, Iran.
| | - Ali Akbar Saboury
- Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran.
| | - Bahram Goliaei
- Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran.
| |
Collapse
|
4
|
Anagnostou D, Sfakianaki G, Melachroinou K, Soutos M, Constantinides V, Vaikath N, Tsantzali I, Paraskevas GP, Agnaf OE, Vekrellis K, Emmanouilidou E. Assessment of Aggregated and Exosome-Associated α-Synuclein in Brain Tissue and Cerebrospinal Fluid Using Specific Immunoassays. Diagnostics (Basel) 2023; 13:2192. [PMID: 37443586 DOI: 10.3390/diagnostics13132192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 06/16/2023] [Accepted: 06/22/2023] [Indexed: 07/15/2023] Open
Abstract
Even though it is currently well-established that α-synuclein aggregation is closely associated with the pathological events in Parkinson's disease (PD) and several other neurodegenerative disorders, collectively called synucleinopathies, the mechanistic link between α-synuclein aggregates and the onset and progression of neurodegeneration in these diseases remain unclear. The process of aggregation initiates from a structurally distorted monomer that gradually oligomerizes to generate a repertoire of fibrillar and oligomeric multimers that deposit within diseased cells in the brain. Total α-synuclein has been proposed as a potential biomarker in PD, but most of the studies do not discriminate between distinct α-synuclein conformers. To correlate protein measurements to disease pathology, we have developed a conformation-specific ELISA method that selectively detects fibrillar and oligomeric forms of α-synuclein without cross-reacting with monomers. We have used this assay to determine the levels of aggregated α-synuclein in human and mouse brain tissue as well as in CSF and CSF-derived exosomes from patients with synucleinopathy and control subjects. Our results verify the ability of the new assay to detect aggregated α-synuclein in complex matrices and support the idea that the levels of these conformers are related to the age of onset in PD patients, while CSF analysis showed that these species exist in low abundance in CSF and CSF-derived exosomes. Future studies will be required to fully assess the diagnostic usefulness of this ELISA in synucleinopathies.
Collapse
Affiliation(s)
- Dimitrios Anagnostou
- Laboratory of Biochemistry, Department of Chemistry, National and Kapodistrian University of Athens, 15784 Athens, Greece
| | - Garifalia Sfakianaki
- Laboratory of Biochemistry, Department of Chemistry, National and Kapodistrian University of Athens, 15784 Athens, Greece
| | - Katerina Melachroinou
- Center for Basic Research, Biomedical Research Foundation Academy of Athens, 11527 Athens, Greece
| | - Miltiadis Soutos
- Center for Basic Research, Biomedical Research Foundation Academy of Athens, 11527 Athens, Greece
| | - Vassilios Constantinides
- Neurochemistry Unit, 1st Department of Neurology, Eginition Hospital, National and Kapodistrian University of Athens, 11528 Athens, Greece
| | - Nishant Vaikath
- Neurological Disorder Research Center, Qatar Biomedical Research Institute (QBRI), Hamad Bin Khalifa University (H.B.K.U.), Qatar Foundation, Doha P.O. Box 34110, Qatar
| | - Ioanna Tsantzali
- 2nd Department of Neurology, Attikon General University Hospital, School of Medicine, National and Kapodistrian University of Athens, 12462 Athens, Greece
| | - George P Paraskevas
- 2nd Department of Neurology, Attikon General University Hospital, School of Medicine, National and Kapodistrian University of Athens, 12462 Athens, Greece
| | - Omar El Agnaf
- Neurological Disorder Research Center, Qatar Biomedical Research Institute (QBRI), Hamad Bin Khalifa University (H.B.K.U.), Qatar Foundation, Doha P.O. Box 34110, Qatar
| | - Kostas Vekrellis
- Center for Basic Research, Biomedical Research Foundation Academy of Athens, 11527 Athens, Greece
| | - Evangelia Emmanouilidou
- Laboratory of Biochemistry, Department of Chemistry, National and Kapodistrian University of Athens, 15784 Athens, Greece
| |
Collapse
|
5
|
Nakajima K, Yamaguchi K, Noji M, Aguirre C, Ikenaka K, Mochizuki H, Zhou L, Ogi H, Ito T, Narita I, Gejyo F, Naiki H, Yamamoto S, Goto Y. Macromolecular crowding and supersaturation protect hemodialysis patients from the onset of dialysis-related amyloidosis. Nat Commun 2022; 13:5689. [PMID: 36192385 PMCID: PMC9530240 DOI: 10.1038/s41467-022-33247-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Accepted: 09/08/2022] [Indexed: 11/09/2022] Open
Abstract
Dialysis-related amyloidosis (DRA), a serious complication among long-term hemodialysis patients, is caused by amyloid fibrils of β2-microglobulin (β2m). Although high serum β2m levels and a long dialysis vintage are the primary and secondary risk factors for the onset of DRA, respectively, patients with these do not always develop DRA, indicating that there are additional risk factors. To clarify these unknown factors, we investigate the effects of human sera on β2m amyloid fibril formation, revealing that sera markedly inhibit amyloid fibril formation. Results from over 100 sera indicate that, although the inhibitory effects of sera deteriorate in long-term dialysis patients, they are ameliorated by maintenance dialysis treatments in the short term. Serum albumin prevents amyloid fibril formation based on macromolecular crowding effects, and decreased serum albumin concentration in dialysis patients is a tertiary risk factor for the onset of DRA. We construct a theoretical model assuming cumulative effects of the three risk factors, suggesting the importance of monitoring temporary and accumulated risks to prevent the development of amyloidosis, which occurs based on supersaturation-limited amyloid fibril formation in a crowded milieu.
Collapse
Affiliation(s)
- Kichitaro Nakajima
- Global Center for Medical Engineering and Informatics, Osaka University, Suita, Osaka, 565-0871, Japan.,Graduate School of Engineering, Osaka University, Suita, Osaka, 565-0871, Japan
| | - Keiichi Yamaguchi
- Global Center for Medical Engineering and Informatics, Osaka University, Suita, Osaka, 565-0871, Japan.,Graduate School of Engineering, Osaka University, Suita, Osaka, 565-0871, Japan
| | - Masahiro Noji
- Graduate School of Human and Environmental Studies, Kyoto University, Yoshidahonmatsu-cho, Sakyo-ku, Kyoto, 606-8316, Japan
| | - César Aguirre
- Department of Neurology, Graduate School of Medicine, Osaka University, Suita, Osaka, 565-0871, Japan
| | - Kensuke Ikenaka
- Department of Neurology, Graduate School of Medicine, Osaka University, Suita, Osaka, 565-0871, Japan
| | - Hideki Mochizuki
- Department of Neurology, Graduate School of Medicine, Osaka University, Suita, Osaka, 565-0871, Japan
| | - Lianjie Zhou
- Graduate School of Engineering, Osaka University, Suita, Osaka, 565-0871, Japan
| | - Hirotsugu Ogi
- Graduate School of Engineering, Osaka University, Suita, Osaka, 565-0871, Japan
| | - Toru Ito
- Division of Clinical Nephrology and Rheumatology, Graduate School of Medical and Dental Sciences, Niigata University, Niigata, 951-8510, Japan
| | - Ichiei Narita
- Division of Clinical Nephrology and Rheumatology, Graduate School of Medical and Dental Sciences, Niigata University, Niigata, 951-8510, Japan
| | - Fumitake Gejyo
- Niigata University of Pharmacy and Applied Life Sciences, Niigata, 956-8603, Japan
| | - Hironobu Naiki
- Faculty of Medical Sciences, University of Fukui, Fukui, 910-1193, Japan
| | - Suguru Yamamoto
- Division of Clinical Nephrology and Rheumatology, Graduate School of Medical and Dental Sciences, Niigata University, Niigata, 951-8510, Japan.
| | - Yuji Goto
- Global Center for Medical Engineering and Informatics, Osaka University, Suita, Osaka, 565-0871, Japan. .,Graduate School of Engineering, Osaka University, Suita, Osaka, 565-0871, Japan.
| |
Collapse
|
6
|
Supersaturation-Dependent Formation of Amyloid Fibrils. Molecules 2022; 27:molecules27144588. [PMID: 35889461 PMCID: PMC9321232 DOI: 10.3390/molecules27144588] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2022] [Revised: 07/11/2022] [Accepted: 07/12/2022] [Indexed: 01/27/2023] Open
Abstract
The supersaturation of a solution refers to a non-equilibrium phase in which the solution is trapped in a soluble state, even though the solute’s concentration is greater than its thermodynamic solubility. Upon breaking supersaturation, crystals form and the concentration of the solute decreases to its thermodynamic solubility. Soon after the discovery of the prion phenomena, it was recognized that prion disease transmission and propagation share some similarities with the process of crystallization. Subsequent studies exploring the structural and functional association between amyloid fibrils and amyloidoses solidified this paradigm. However, recent studies have not necessarily focused on supersaturation, possibly because of marked advancements in structural studies clarifying the atomic structures of amyloid fibrils. On the other hand, there is increasing evidence that supersaturation plays a critical role in the formation of amyloid fibrils and the onset of amyloidosis. Here, we review the recent evidence that supersaturation plays a role in linking unfolding/folding and amyloid fibril formation. We also introduce the HANABI (HANdai Amyloid Burst Inducer) system, which enables high-throughput analysis of amyloid fibril formation by the ultrasonication-triggered breakdown of supersaturation. In addition to structural studies, studies based on solubility and supersaturation are essential both to developing a comprehensive understanding of amyloid fibrils and their roles in amyloidosis, and to developing therapeutic strategies.
Collapse
|
7
|
Development of HANABI, an ultrasonication-forced amyloid fibril inducer. Neurochem Int 2021; 153:105270. [PMID: 34954259 DOI: 10.1016/j.neuint.2021.105270] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Revised: 12/16/2021] [Accepted: 12/21/2021] [Indexed: 12/20/2022]
Abstract
Amyloid fibrils involved in amyloidoses are crystal-like aggregates, which are formed by breaking supersaturation of denatured proteins. Ultrasonication is an efficient method of agitation for breaking supersaturation and thus inducing amyloid fibrils. By combining an ultrasonicator and a microplate reader, we developed the HANABI (HANdai Amyloid Burst Inducer) system that enables high-throughput analysis of amyloid fibril formation. Among high-throughput approaches of amyloid fibril assays, the HANABI system has advantages in accelerating and detecting spontaneous amyloid fibril formation. HANABI is also powerful for amplifying a tiny amount of preformed amyloid fibrils by seeding. Thus, HANABI will contribute to creating therapeutic strategies against amyloidoses by identifying their biomarkers.
Collapse
|
8
|
Yamaguchi K, Hasuo K, So M, Ikenaka K, Mochizuki H, Goto Y. Strong acids induce amyloid fibril formation of β 2-microglobulin via an anion-binding mechanism. J Biol Chem 2021; 297:101286. [PMID: 34626645 PMCID: PMC8564678 DOI: 10.1016/j.jbc.2021.101286] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 10/01/2021] [Accepted: 10/05/2021] [Indexed: 11/28/2022] Open
Abstract
Amyloid fibrils, crystal-like fibrillar aggregates of proteins associated with various amyloidoses, have the potential to propagate via a prion-like mechanism. Among known methodologies to dissolve preformed amyloid fibrils, acid treatment has been used with the expectation that the acids will degrade amyloid fibrils similar to acid inactivation of protein functions. Contrary to our expectation, treatment with strong acids, such as HCl or H2SO4, of β2-microglobulin (β2m) or insulin actually promoted amyloid fibril formation, proportionally to the concentration of acid used. A similar promotion was observed at pH 2.0 upon the addition of salts, such as NaCl or Na2SO4. Although trichloroacetic acid, another strong acid, promoted amyloid fibril formation of β2m, formic acid, a weak acid, did not, suggesting the dominant role of anions in promoting fibril formation of this protein. Comparison of the effects of acids and salts confirmed the critical role of anions, indicating that strong acids likely induce amyloid fibril formation via an anion-binding mechanism. The results suggest that although the addition of strong acids decreases pH, it is not useful for degrading amyloid fibrils, but rather induces or stabilizes amyloid fibrils via an anion-binding mechanism.
Collapse
Affiliation(s)
- Keiichi Yamaguchi
- Global Center for Medical Engineering and Informatics, Osaka University, Suita, Osaka, Japan; Institute for Protein Research, Osaka University, Suita, Osaka, Japan
| | - Kenshiro Hasuo
- Institute for Protein Research, Osaka University, Suita, Osaka, Japan
| | - Masatomo So
- Institute for Protein Research, Osaka University, Suita, Osaka, Japan
| | - Kensuke Ikenaka
- Department of Neurology, Graduate School of Medicine, Osaka University, Suita, Osaka, Japan
| | - Hideki Mochizuki
- Department of Neurology, Graduate School of Medicine, Osaka University, Suita, Osaka, Japan
| | - Yuji Goto
- Global Center for Medical Engineering and Informatics, Osaka University, Suita, Osaka, Japan; Institute for Protein Research, Osaka University, Suita, Osaka, Japan.
| |
Collapse
|
9
|
Nakajima K, Toda H, Yamaguchi K, So M, Ikenaka K, Mochizuki H, Goto Y, Ogi H. Half-Time Heat Map Reveals Ultrasonic Effects on Morphology and Kinetics of Amyloidogenic Aggregation Reaction. ACS Chem Neurosci 2021; 12:3456-3466. [PMID: 34467753 DOI: 10.1021/acschemneuro.1c00461] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Ultrasonication has been recently adopted in amyloid-fibril assays because of its ability to accelerate fibril formation, being promising in the early stage diagnosis of amyloidoses in clinical applications. Although applications of this technique are expanding in the field of protein science, its effects on the aggregation reactions of amyloidogenic proteins are poorly understood. In this study, we comprehensively investigated the morphology and structure of resultant aggregates, kinetics of fibril formation, and seed-detection sensitivity under ultrasonication using β2-microglobulin and compared these characteristics under shaking, which has been traditionally adopted in amyloid-fibril assays. To discuss the ultrasonic effects on the amyloid-fibril formation, we propose the half-time heat map, which describes the phase diagram of the aggregation reaction of amyloidogenic proteins. The experimental results show that ultrasonication greatly promotes fibril formation, especially in dilute monomer solutions, induces short-dispersed fibrils, and is capable of detecting ultra-trace-concentration seeds with a detection limit of 10 fM. Furthermore, we indicate that ultrasonication highly alters the energy landscape of an aggregation reaction due to the effect of ultrasonic cavitation. These insights contribute not only to our understanding of the effects of agitation on amyloidogenic aggregation reactions but also to their effective application in the clinical diagnosis of amyloidoses.
Collapse
Affiliation(s)
- Kichitaro Nakajima
- Global Center for Medical Engineering and Informatics, Osaka University, Suita, Osaka 565-0871, Japan
| | - Hajime Toda
- Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871, Japan
| | - Keiichi Yamaguchi
- Global Center for Medical Engineering and Informatics, Osaka University, Suita, Osaka 565-0871, Japan
| | - Masatomo So
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, U.K
| | - Kensuke Ikenaka
- Department of Neurology, Graduate School of Medicine, Osaka University, Suita, Osaka 565-0871, Japan
| | - Hideki Mochizuki
- Department of Neurology, Graduate School of Medicine, Osaka University, Suita, Osaka 565-0871, Japan
| | - Yuji Goto
- Global Center for Medical Engineering and Informatics, Osaka University, Suita, Osaka 565-0871, Japan
| | - Hirotsugu Ogi
- Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871, Japan
| |
Collapse
|
10
|
So M, Kimura Y, Yamaguchi K, Sugiki T, Fujiwara T, Aguirre C, Ikenaka K, Mochizuki H, Kawata Y, Goto Y. Polyphenol-solubility alters amyloid fibril formation of α-synuclein. Protein Sci 2021; 30:1701-1713. [PMID: 34046949 DOI: 10.1002/pro.4130] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 05/10/2021] [Accepted: 05/18/2021] [Indexed: 12/18/2022]
Abstract
Amyloid fibril formation is associated with various amyloidoses, including neurodegenerative diseases such as Alzheimer's and Parkinson's diseases. Amyloid fibrils form above the solubility of amyloidogenic proteins or peptides upon breaking supersaturation, followed by a nucleation and elongation mechanism, which is similar to the crystallization of solutes. Many additives, including salts, detergents, and natural compounds, promote or inhibit amyloid formation. However, the underlying mechanisms of the opposing effects are unclear. We examined the effects of two polyphenols, that is, epigallocatechin gallate (EGCG) and kaempferol-7─O─glycoside (KG), with high and low solubilities, respectively, on the amyloid formation of α-synuclein (αSN). EGCG and KG inhibited and promoted amyloid formation of αSN, respectively, when monitored by thioflavin T (ThT) fluorescence or transmission electron microscopy (TEM). Nuclear magnetic resonance (NMR) analysis revealed that, although interactions of αSN with soluble EGCG increased the solubility of αSN, thus inhibiting amyloid formation, interactions of αSN with insoluble KG reduced the solubility of αSN, thereby promoting amyloid formation. Our study suggests that opposing effects of polyphenols on amyloid formation of proteins and peptides can be interpreted based on the solubility of polyphenols.
Collapse
Affiliation(s)
- Masatomo So
- Institute for Protein Research, Osaka University, Osaka, Japan.,Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, UK
| | - Yuto Kimura
- Institute for Protein Research, Osaka University, Osaka, Japan
| | - Keiichi Yamaguchi
- Institute for Protein Research, Osaka University, Osaka, Japan.,Global Center for Medical Engineering and Informatics, Osaka University, Osaka, Japan
| | | | | | - Cesar Aguirre
- Institute for Protein Research, Osaka University, Osaka, Japan.,Department of Neurology, Graduate School of Medicine, Osaka University, Osaka, Japan
| | - Kensuke Ikenaka
- Department of Neurology, Graduate School of Medicine, Osaka University, Osaka, Japan
| | - Hideki Mochizuki
- Department of Neurology, Graduate School of Medicine, Osaka University, Osaka, Japan
| | - Yasushi Kawata
- Department of Chemistry and Biotechnology, Graduate School of Engineering, Tottori University, Tottori, Japan
| | - Yuji Goto
- Institute for Protein Research, Osaka University, Osaka, Japan.,Global Center for Medical Engineering and Informatics, Osaka University, Osaka, Japan
| |
Collapse
|
11
|
Nakajima K, Noi K, Yamaguchi K, So M, Ikenaka K, Mochizuki H, Ogi H, Goto Y. Optimized sonoreactor for accelerative amyloid-fibril assays through enhancement of primary nucleation and fragmentation. ULTRASONICS SONOCHEMISTRY 2021; 73:105508. [PMID: 33770746 PMCID: PMC7994783 DOI: 10.1016/j.ultsonch.2021.105508] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 02/19/2021] [Accepted: 02/26/2021] [Indexed: 06/12/2023]
Abstract
Ultrasonication to supersaturated protein solutions forcibly forms amyloid fibrils, thereby allowing the early-stage diagnosis for amyloidoses. Previously, we constructed a high-throughput sonoreactor to investigate features of the amyloid-fibril nucleation. Although the instrument substantiated the ultrasonication efficacy, several challenges remain; the key is the precise control of the acoustic field in the reactor, which directly affects the fibril-formation reaction. In the present study, we develop the optimized sonoreactor for the amyloid-fibril assay, which improves the reproducibility and controllability of the fibril formation. Using β2-microglobulin, we experimentally demonstrate that achieving identical acoustic conditions by controlling oscillation amplitude and frequency of each transducer results in identical fibril-formation behavior across 36 solutions. Moreover, we succeed in detecting the 100-fM seeds using the developed sonoreactor at an accelerated rate. Finally, we reveal that the acceleration of the fibril-formation reaction with the seeds is achieved by enhancing the primary nucleation and the fibril fragmentation through the analysis of the fibril-formation kinetics. These results demonstrate the efficacy of the developed sonoreactor for the diagnosis of amyloidoses owing to the accelerative seed detection and the possibility for further early-stage diagnosis even without seeds through the accelerated primary nucleation.
Collapse
Affiliation(s)
- Kichitaro Nakajima
- Global Center for Medical Engineering and Informatics, Osaka University, Suita, Osaka 565-0871, Japan
| | - Kentaro Noi
- Institute for NanoScience Design, Osaka University, Toyonaka, Osaka 560-8531, Japan
| | - Keiichi Yamaguchi
- Global Center for Medical Engineering and Informatics, Osaka University, Suita, Osaka 565-0871, Japan
| | - Masatomo So
- Institute for Protein Research, Osaka University, Suita, Osaka 565-0871, Japan
| | - Kensuke Ikenaka
- Department of Neurology, Graduated School of Medicine, Osaka University, Suita, Osaka 565-0871, Japan
| | - Hideki Mochizuki
- Department of Neurology, Graduated School of Medicine, Osaka University, Suita, Osaka 565-0871, Japan
| | - Hirotsugu Ogi
- Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871, Japan.
| | - Yuji Goto
- Global Center for Medical Engineering and Informatics, Osaka University, Suita, Osaka 565-0871, Japan.
| |
Collapse
|
12
|
Chen X, Deng X, Han X, Liang Y, Meng Z, Liu R, Su W, Zhu H, Fu T. Inhibition of Lysozyme Amyloid Fibrillation by Silybin Diastereoisomers: The Effects of Stereochemistry. ACS OMEGA 2021; 6:3307-3318. [PMID: 33553948 PMCID: PMC7860231 DOI: 10.1021/acsomega.0c05788] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2020] [Accepted: 01/08/2021] [Indexed: 05/24/2023]
Abstract
Silybin is a flavonoid lignin compound consisting of two diastereomers with nearly equal molar ratios. It has been reported that silybin can effectively inhibit the aggregation of amyloid protein, but the difference between the two silybin diastereomers has been rarely studied. In this work, the inhibitory ability of silybin to hen egg-white lysozyme (HEWL) was demonstrated, and the difference of kinetic parameters of two diastereomers was analyzed. Fluorescence quenching titration was utilized to analyze the binding differences to native HEWL between the diastereomers, and transmission electron microscopy (TEM) was utilized to analyze the characteristics of the surface of various samples. The differences between hydrophobicity and the secondary structure among several HEWL samples were measured by the 8-anilino-1-naphthalene sulfonic (ANS) acid fluorescence probe, Raman spectra, and far-UV circular dichroism. Moreover, the differences in the binding energy of these two diastereomers with HEWL were analyzed by molecular docking. Also, we have investigated the effect of silybin diastereomers on HEWL fibril-induced cytotoxicity in SH-SY5Y cells. Results show that silybin has a certain inhibitory effect on the HEWL fibrillogenesis process, while silybin B (SB) has a more significant inhibitory effect than silybin A (SA), especially at high concentrations. This work provides some insights into the screening of amyloid inhibitors from complicated natural products and indicates that SB has the prospect of further development as an amyloid inhibitor.
Collapse
Affiliation(s)
- Xuanyu Chen
- School
of Pharmacy, Nanjing University of Chinese
Medicine, Nanjing 210023, China
- Plant
Medicine Research and Technological Development Center of Jiangsu
Province, Nanjing 210023, China
| | - Xiaomin Deng
- School
of Pharmacy, Nanjing University of Chinese
Medicine, Nanjing 210023, China
- Plant
Medicine Research and Technological Development Center of Jiangsu
Province, Nanjing 210023, China
| | - Xingxing Han
- School
of Pharmacy, Nanjing University of Chinese
Medicine, Nanjing 210023, China
- Plant
Medicine Research and Technological Development Center of Jiangsu
Province, Nanjing 210023, China
| | - Yinmei Liang
- School
of Pharmacy, Nanjing University of Chinese
Medicine, Nanjing 210023, China
- Plant
Medicine Research and Technological Development Center of Jiangsu
Province, Nanjing 210023, China
| | - Zhiping Meng
- School
of Pharmacy, Nanjing University of Chinese
Medicine, Nanjing 210023, China
- Plant
Medicine Research and Technological Development Center of Jiangsu
Province, Nanjing 210023, China
| | - Rui Liu
- School
of Pharmacy, Nanjing University of Chinese
Medicine, Nanjing 210023, China
| | - Wenqiang Su
- School
of Pharmacy, Nanjing University of Chinese
Medicine, Nanjing 210023, China
- Plant
Medicine Research and Technological Development Center of Jiangsu
Province, Nanjing 210023, China
| | - Huaxu Zhu
- School
of Pharmacy, Nanjing University of Chinese
Medicine, Nanjing 210023, China
- Plant
Medicine Research and Technological Development Center of Jiangsu
Province, Nanjing 210023, China
- Separation
Engineering of Chinese Traditional Medicine Compound, Nanjing University of Chinese Medicine, Nanjing 210023, China
| | - Tingming Fu
- School
of Pharmacy, Nanjing University of Chinese
Medicine, Nanjing 210023, China
- Plant
Medicine Research and Technological Development Center of Jiangsu
Province, Nanjing 210023, China
- Separation
Engineering of Chinese Traditional Medicine Compound, Nanjing University of Chinese Medicine, Nanjing 210023, China
| |
Collapse
|
13
|
Sawada M, Yamaguchi K, Hirano M, Noji M, So M, Otzen D, Kawata Y, Goto Y. Amyloid Formation of α-Synuclein Based on the Solubility- and Supersaturation-Dependent Mechanism. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:4671-4681. [PMID: 32271585 DOI: 10.1021/acs.langmuir.0c00426] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Amyloid fibrils are formed by denatured proteins when the supersaturation of denatured proteins is broken by agitation, such as ultrasonication, or by seeding, although the detailed mechanism of how solubility and supersaturation regulate amyloid formation remains unclear. To further understand the mechanism of amyloid formation, we examined α-synuclein (α-syn) amyloid formation at varying concentrations of SDS, LPA, heparin, or NaCl at pH 7.5. Amyloid fibrils were formed below or around the critical micelle concentrations (CMCs) of SDS (2.75 mM) and LPA (0.24 mM), although no fibrils were formed above the CMCs. On the other hand, amyloid fibrils were formed with 0.01-2.5 mg/mL of heparin and 0.5-1.0 M NaCl, and amyloid formation was gradually suppressed at higher concentrations of heparin and NaCl. To reproduce these concentration-dependent effects of additives, we constructed two models: (i) the ligand-binding-dependent solubility-modulation model and (ii) the cosolute-dependent direct solubility-modulation model, both of which were used by Tanford and colleagues to analyze the additive-dependent conformational transitions of proteins. The solubility of α-syn was assumed to vary depending on the concentration of additives either by the decreased solubility of the additive-α-syn complex (model i) or by the direct regulation of α-syn solubility (model ii). Both models well reproduced additive-dependent bell-shaped profiles of acceleration and inhibition observed for SDS and LPA. As for heparin and NaCl, participation of amorphous aggregates at high concentrations of additives was suggested. The models confirmed that solubility and supersaturation play major roles in driving amyloid formation in vitro, furthering our understanding of the pathogenesis of amyloidosis in vivo.
Collapse
Affiliation(s)
- Maya Sawada
- Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Keiichi Yamaguchi
- Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Miki Hirano
- Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Masahiro Noji
- Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Masatomo So
- Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Daniel Otzen
- Interdisciplinary Nanoscience Center (iNANO), Department of Molecular Biology, Aarhus University, Gustav Wieds Vej 10C, DK-8000 Aarhus C, Denmark
| | - Yasushi Kawata
- Department of Chemistry and Biotechnology, Graduate School of Engineering, Tottori University, 4-101 Koyama Minami, Tottori 680-8552, Japan
| | - Yuji Goto
- Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565-0871, Japan
| |
Collapse
|
14
|
Furukawa K, Aguirre C, So M, Sasahara K, Miyanoiri Y, Sakurai K, Yamaguchi K, Ikenaka K, Mochizuki H, Kardos J, Kawata Y, Goto Y. Isoelectric point-amyloid formation of α-synuclein extends the generality of the solubility and supersaturation-limited mechanism. Curr Res Struct Biol 2020; 2:35-44. [PMID: 34235468 PMCID: PMC8244297 DOI: 10.1016/j.crstbi.2020.03.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Revised: 03/02/2020] [Accepted: 03/30/2020] [Indexed: 12/30/2022] Open
Abstract
Proteins in either a native or denatured conformation often aggregate at an isoelectric point (pI), a phenomenon known as pI precipitation. However, only a few studies have addressed the role of pI precipitation in amyloid formation, the crystal-like aggregation of denatured proteins. We found that α-synuclein, an intrinsically disordered protein of 140 amino acid residues associated with Parkinson's disease, formed amyloid fibrils at pI (= 4.7) under the low-sodium phosphate conditions. Although α-synuclein also formed amyloid fibrils at a wide pH range under high concentrations of sodium phosphate, the pI-amyloid formation was characterized by marked amyloid-specific thioflavin T fluorescence and clear fibrillar morphology, indicating highly ordered structures. Analysis by heteronuclear NMR in combination with principal component analysis suggested that amyloid formation under low and high phosphate conditions occurred by distinct mechanisms. The former was likely to be caused by the intermolecular attractive charge-charge interactions, where α-synuclein has +17 and −17 charges even with the zero net charge. On the other hand, the latter was caused by the phosphate-dependent salting-out effects. pI-amyloid formation may play a role in the membrane-dependent amyloid formation of α-synuclein, where the negatively charged membrane surface reduces the local pH to pI and the membrane hydrophobic environment enhances electrostatic interactions. The results extend the supersaturation-limited mechanism of amyloid formation: Amyloid fibrils are formed under a variety of conditions of decreased solubility of denatured proteins triggered by the breakdown of supersaturation. pI precipitation of α-synuclein led to the formation of amyloid fibrils. Fibrils formed at pI were more organized than those formed under other conditions. Attractive charge-charge interactions are responsible for the pI-amyloid formation. pI-amyloid formation may lead to the amyloid formation upon phospholipid membranes.
Collapse
Affiliation(s)
- Koki Furukawa
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka, 565-0871, Japan
| | - Cesar Aguirre
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka, 565-0871, Japan
| | - Masatomo So
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka, 565-0871, Japan
| | - Kenji Sasahara
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka, 565-0871, Japan
| | - Yohei Miyanoiri
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka, 565-0871, Japan
| | - Kazumasa Sakurai
- Institute of Advanced Technology, Kindai University, Wakayama, 649-6493, Japan
| | - Keiichi Yamaguchi
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka, 565-0871, Japan
| | - Kensuke Ikenaka
- Department of Neurology, Graduate School of Medicine, Osaka University, Yamadaoka 2-2, Suita, Osaka, 565-0871, Japan
| | - Hideki Mochizuki
- Department of Neurology, Graduate School of Medicine, Osaka University, Yamadaoka 2-2, Suita, Osaka, 565-0871, Japan
| | - Jozsef Kardos
- ELTE NAP Neuroimmunology Research Group, Department of Biochemistry, Eötvös Loránd University, Pázmány P. Sétány 1/C, Budapest, 1117, Hungary
| | - Yasushi Kawata
- Department of Chemistry and Biotechnology, Graduate School of Engineering, Tottori University, Tottori, 680-8552, Japan
| | - Yuji Goto
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka, 565-0871, Japan
| |
Collapse
|
15
|
Taricska N, Horváth D, Menyhárd DK, Ákontz-Kiss H, Noji M, So M, Goto Y, Fujiwara T, Perczel A. The Route from the Folded to the Amyloid State: Exploring the Potential Energy Surface of a Drug-Like Miniprotein. Chemistry 2019; 26:1968-1978. [PMID: 31647140 PMCID: PMC7028080 DOI: 10.1002/chem.201903826] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Indexed: 12/16/2022]
Abstract
The amyloid formation of the folded segment of a variant of Exenatide (a marketed drug for type‐2 diabetes mellitus) was studied by electronic circular dichroism (ECD) and NMR spectroscopy. We found that the optimum temperature for E5 protein amyloidosis coincides with body temperature and requires well below physiological salt concentration. Decomposition of the ECD spectra and its barycentric representation on the folded‐unfolded‐amyloid potential energy surface allowed us to monitor the full range of molecular transformation of amyloidogenesis. We identified points of no return (e.g.; T=37 °C, pH 4.1, cE5=250 μm, cNaCl=50 mm, t>4–6 h) that will inevitably gravitate into the amyloid state. The strong B‐type far ultraviolet (FUV)‐ECD spectra and an unexpectedly strong near ultraviolet (NUV)‐ECD signal (Θ≈275–285
nm) indicate that the amyloid phase of E5 is built from monomers of quasi‐elongated backbone structure (φ≈−145°, ψ≈+145°) with strong interstrand Tyr↔Trp interaction. Misfolded intermediates and the buildup of “toxic” early‐stage oligomers leading to self‐association were identified and monitored as a function of time. Results indicate that the amyloid transition is triggered by subtle misfolding of the α‐helix, exposing aromatic and hydrophobic side chains that may provide the first centers for an intermolecular reorganization. These initial clusters provide the spatial closeness and sufficient time for a transition to the β‐structured amyloid nucleus, thus the process follows a nucleated growth mechanism.
Collapse
Affiliation(s)
- Nóra Taricska
- Laboratory of Structural Chemistry and Biology &, MTA-ELTE Protein Modeling Research Group, Eötvös Loránd University, Pázmány Péter sétány 1A, 1117, Budapest, Hungary
| | - Dániel Horváth
- Laboratory of Structural Chemistry and Biology &, MTA-ELTE Protein Modeling Research Group, Eötvös Loránd University, Pázmány Péter sétány 1A, 1117, Budapest, Hungary
| | - Dóra K Menyhárd
- Laboratory of Structural Chemistry and Biology &, MTA-ELTE Protein Modeling Research Group, Eötvös Loránd University, Pázmány Péter sétány 1A, 1117, Budapest, Hungary
| | - Hanna Ákontz-Kiss
- Laboratory of Structural Chemistry and Biology &, MTA-ELTE Protein Modeling Research Group, Eötvös Loránd University, Pázmány Péter sétány 1A, 1117, Budapest, Hungary
| | - Masahiro Noji
- Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Masatomo So
- Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Yuji Goto
- Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Toshimichi Fujiwara
- Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - András Perczel
- Laboratory of Structural Chemistry and Biology &, MTA-ELTE Protein Modeling Research Group, Eötvös Loránd University, Pázmány Péter sétány 1A, 1117, Budapest, Hungary
| |
Collapse
|
16
|
Hayakawa H, Nakatani R, Ikenaka K, Aguirre C, Choong CJ, Tsuda H, Nagano S, Koike M, Ikeuchi T, Hasegawa M, Papa SM, Nagai Y, Mochizuki H, Baba K. Structurally distinct α-synuclein fibrils induce robust parkinsonian pathology. Mov Disord 2019; 35:256-267. [PMID: 31643109 DOI: 10.1002/mds.27887] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Revised: 07/24/2019] [Accepted: 08/26/2019] [Indexed: 12/16/2022] Open
Abstract
OBJECTIVE Alpha-synuclein (α-syn) is a major component of Lewy bodies, which are the pathological hallmark in Parkinson's disease, and its genetic mutations cause familial forms of Parkinson's disease. Patients with α-syn G51D mutation exhibit severe clinical symptoms. However, in vitro studies showed low propensity for α-syn with the G51D mutation. We studied the mechanisms associated with severe neurotoxicity of α-syn G51D mutation using a murine model generated by G51D α-syn fibril injection into the brain. METHODS Structural analysis of wild-type and G51D α-syn-fibrils were performed using Fourier transform infrared spectroscopy. The ability of α-syn fibrils forming aggregates was first assessed in in vitro mammalian cells. An in vivo mouse model with an intranigral injection of α-syn fibrils was then used to evaluate the propagation pattern of α-syn and related cellular changes. RESULTS We found that G51D α-syn fibrils have higher β-sheet contents than wild-type α-syn fibrils. The addition of G51D α-syn fibrils to mammalian cells overexpressing α-syn resulted in the formation of phosphorylated α-syn inclusions at a higher rate. Similarly, an injection of G51D α-syn fibrils into the substantia nigra of a mouse brain induced more widespread phosphorylated α-syn pathology. Notably, the mice injected with G51D α-syn fibrils exhibited progressive nigral neuronal loss accompanied with mitochondrial abnormalities and motor impairment. CONCLUSION Our findings indicate that the structural difference of G51D α-syn fibrils plays an important role in the rapidly developed and more severe neurotoxicity of G51D mutation-linked Parkinson's disease. © 2019 International Parkinson and Movement Disorder Society.
Collapse
Affiliation(s)
- Hideki Hayakawa
- Department of Neurology, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Rie Nakatani
- Department of Neurology, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Kensuke Ikenaka
- Department of Neurology, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Cesar Aguirre
- Institute of Protein Research, Osaka University, Osaka, Japan
| | - Chi-Jing Choong
- Department of Neurology, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Hiroshi Tsuda
- Department of Neurology, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Seiichi Nagano
- Department of Neurology, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Masato Koike
- Department of Cell Biology and Neuroscience, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Takeshi Ikeuchi
- Department of Molecular Genetics, Bioresource Science Branch, Center for Bioresources, Brain Research Institute, Niigata University, Niigata, Japan
| | - Masato Hasegawa
- Department of Neuropathology and Cell Biology, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Stella M Papa
- Department of Neurology, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Yoshitaka Nagai
- Department of Neurology, Osaka University Graduate School of Medicine, Osaka, Japan.,Department of Neurotherapeutics, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Hideki Mochizuki
- Department of Neurology, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Kousuke Baba
- Department of Neurology, Osaka University Graduate School of Medicine, Osaka, Japan
| |
Collapse
|
17
|
Kakuda K, Ikenaka K, Araki K, So M, Aguirre C, Kajiyama Y, Konaka K, Noi K, Baba K, Tsuda H, Nagano S, Ohmichi T, Nagai Y, Tokuda T, El-Agnaf OMA, Ogi H, Goto Y, Mochizuki H. Ultrasonication-based rapid amplification of α-synuclein aggregates in cerebrospinal fluid. Sci Rep 2019; 9:6001. [PMID: 30979935 PMCID: PMC6461702 DOI: 10.1038/s41598-019-42399-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Accepted: 03/13/2019] [Indexed: 12/19/2022] Open
Abstract
α-Synuclein aggregates, a key hallmark of the pathogenesis of Parkinson’s disease, can be amplified by using their seeding activity, and the evaluation of the seeding activity of cerebrospinal fluid (CSF) is reportedly useful for diagnosis. However, conventional shaking-based assays are time-consuming procedures, and the clinical significance of the diversity of seeding activity among patients remains to be clarified. Previously, we reported a high-throughput ultrasonication-induced amyloid fibrillation assay. Here, we adapted this assay to amplify and detect α-synuclein aggregates from CSF, and investigated the correlation between seeding activity and clinical indicators. We confirmed that this assay could detect α-synuclein aggregates prepared in vitro and also aggregates released from cultured cells. The seeding activity of CSF correlated with the levels of α-synuclein oligomers measured by an enzyme-linked immunosorbent assay. Moreover, the seeding activity of CSF from patients with Parkinson’s disease was higher than that of control patients. Notably, the lag time of patients with Parkinson’s disease was significantly correlated with the MIBG heart-to-mediastinum ratio. These findings showed that our ultrasonication-based assay can rapidly amplify misfolded α-synuclein and can evaluate the seeding activity of CSF.
Collapse
Affiliation(s)
- Keita Kakuda
- Department of Neurology, Graduate School of Medicine, Osaka University, Yamadaoka 2-2, Suita, Osaka, 565-0871, Japan
| | - Kensuke Ikenaka
- Department of Neurology, Graduate School of Medicine, Osaka University, Yamadaoka 2-2, Suita, Osaka, 565-0871, Japan
| | - Katsuya Araki
- Department of Neurology, Graduate School of Medicine, Osaka University, Yamadaoka 2-2, Suita, Osaka, 565-0871, Japan
| | - Masatomo So
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka, 565-0871, Japan
| | - César Aguirre
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka, 565-0871, Japan
| | - Yuta Kajiyama
- Department of Neurology, Graduate School of Medicine, Osaka University, Yamadaoka 2-2, Suita, Osaka, 565-0871, Japan
| | - Kuni Konaka
- Department of Neurology, Graduate School of Medicine, Osaka University, Yamadaoka 2-2, Suita, Osaka, 565-0871, Japan
| | - Kentaro Noi
- Department of Precision Science and Technology, Graduate School of Engineering, Osaka University, Yamadaoka 2-1, Suita, Osaka, 565-0871, Japan
| | - Kousuke Baba
- Department of Neurology, Graduate School of Medicine, Osaka University, Yamadaoka 2-2, Suita, Osaka, 565-0871, Japan
| | - Hiroshi Tsuda
- Department of Neurology, Graduate School of Medicine, Osaka University, Yamadaoka 2-2, Suita, Osaka, 565-0871, Japan
| | - Seiichi Nagano
- Department of Neurology, Graduate School of Medicine, Osaka University, Yamadaoka 2-2, Suita, Osaka, 565-0871, Japan
| | - Takuma Ohmichi
- Department of Neurology, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kamikyo-ku, Kyoto, 602-8566, Japan
| | - Yoshitaka Nagai
- Department of Neurotherapeutics, Graduate school of Medicine, Osaka University, Yamadaoka 2-2, Suita, Osaka, 565-0871, Japan
| | - Takahiko Tokuda
- Department of Molecular Pathobiology of Brain Diseases, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kamikyo-ku, Kyoto, 602-8566, Japan
| | - Omar M A El-Agnaf
- Life Sciences Division, College of Science and Engineering, Hamad Bin Khalifa University (HBKU), Education City, Qatar
| | - Hirotsugu Ogi
- Department of Precision Science and Technology, Graduate School of Engineering, Osaka University, Yamadaoka 2-1, Suita, Osaka, 565-0871, Japan
| | - Yuji Goto
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka, 565-0871, Japan
| | - Hideki Mochizuki
- Department of Neurology, Graduate School of Medicine, Osaka University, Yamadaoka 2-2, Suita, Osaka, 565-0871, Japan.
| |
Collapse
|
18
|
Parnetti L, Gaetani L, Eusebi P, Paciotti S, Hansson O, El-Agnaf O, Mollenhauer B, Blennow K, Calabresi P. CSF and blood biomarkers for Parkinson's disease. Lancet Neurol 2019; 18:573-586. [PMID: 30981640 DOI: 10.1016/s1474-4422(19)30024-9] [Citation(s) in RCA: 323] [Impact Index Per Article: 64.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Revised: 12/21/2018] [Accepted: 01/15/2019] [Indexed: 01/09/2023]
Abstract
In the management of Parkinson's disease, reliable diagnostic and prognostic biomarkers are urgently needed. The diagnosis of Parkinson's disease mostly relies on clinical symptoms, which hampers the detection of the earliest phases of the disease-the time at which treatment with forthcoming disease-modifying drugs could have the greatest therapeutic effect. Reliable prognostic markers could help in predicting the response to treatments. Evidence suggests potential diagnostic and prognostic value of CSF and blood biomarkers closely reflecting the pathophysiology of Parkinson's disease, such as α-synuclein species, lysosomal enzymes, markers of amyloid and tau pathology, and neurofilament light chain. A combination of multiple CSF biomarkers has emerged as an accurate diagnostic and prognostic model. With respect to early diagnosis, the measurement of CSF α-synuclein aggregates is providing encouraging preliminary results. Blood α-synuclein species and neurofilament light chain are also under investigation because they would provide a non-invasive tool, both for early and differential diagnosis of Parkinson's disease versus atypical parkinsonian disorders, and for disease monitoring. In view of adopting CSF and blood biomarkers for improving Parkinson's disease diagnostic and prognostic accuracy, further validation in large independent cohorts is needed.
Collapse
Affiliation(s)
- Lucilla Parnetti
- Section of Neurology, Laboratory of Clinical Neurochemistry, Department of Medicine, University of Perugia, Perugia, Italy.
| | - Lorenzo Gaetani
- Section of Neurology, Department of Medicine, University of Perugia, Perugia, Italy
| | - Paolo Eusebi
- Section of Neurology, Department of Medicine, University of Perugia, Perugia, Italy
| | - Silvia Paciotti
- Section of Neurology, Laboratory of Clinical Neurochemistry, Department of Medicine, University of Perugia, Perugia, Italy; Section of Physiology and Biochemistry, Department of Experimental Medicine, University of Perugia, Perugia, Italy
| | - Oskar Hansson
- Clinical Memory Research Unit, Department of Clinical Sciences Malmö, Lund University, Malmö, Sweden; Memory Clinic, Skåne University Hospital, Malmö, Sweden
| | - Omar El-Agnaf
- Neurological Disorders Research Center, Qatar Biomedical Research Institute, Hamad Bin Khalifa University, Education City, Doha, Qatar
| | - Brit Mollenhauer
- Paracelsus-Elena-Klinik, Kassel, Germany; University Medical Center, Department of Neurology, Göttingen, Germany
| | - Kaj Blennow
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden; Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
| | - Paolo Calabresi
- Section of Neurology, Department of Medicine, University of Perugia, Perugia, Italy; IRCCS Fondazione Santa Lucia, Rome, Italy
| |
Collapse
|
19
|
Ghag G, Bhatt N, Cantu DV, Guerrero‐Munoz MJ, Ellsworth A, Sengupta U, Kayed R. Soluble tau aggregates, not large fibrils, are the toxic species that display seeding and cross-seeding behavior. Protein Sci 2018; 27:1901-1909. [PMID: 30125425 PMCID: PMC6201727 DOI: 10.1002/pro.3499] [Citation(s) in RCA: 84] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Revised: 08/16/2018] [Accepted: 08/16/2018] [Indexed: 11/08/2022]
Abstract
Several studies have proposed that fibrillary aggregates of tau and other amyloidogenic proteins are neurotoxic and result in numerous neurodegenerative diseases. However, these studies usually involve sonication or extrusion through needles before experimentation. As a consequence, these methods may fragment large aggregates producing a mixture of aggregated species rather than intact fibrils. Therefore, the results of these experiments may be reflective of other amyloidogenic species, such as oligomers and/or protofibrils/short fibrils. To investigate the effects of sonication on the aggregation of tau and other amyloidogenic proteins, fibrils were prepared and well characterized, then sonicated and evaluated by various biochemical and biophysical methods to identify the aggregated species present. We found that indeed a mixture of aggregated species was present along with short fibrils indicating that sonication leads to impure fibril samples and should be analyzed with caution. Our results corroborate the previous studies showing that sonication of prion and Aβ fibrils leads to the formation of toxic, soluble aggregates. We also show that the oligomeric forms are the most toxic species although it is unclear how sonication causes oligomer formation. Recent results suggest that these small toxic oligomers produced by sonication, rather than the stable fibrillar structures, are prion-like in nature displaying seeding and cross-seeding behavior.
Collapse
Affiliation(s)
- Gaurav Ghag
- Mitchell Center for Neurodegenerative DiseasesUniversity of Texas Medical BranchGalvestonTexas 77555
- Department of NeurologyUniversity of Texas Medical BranchGalvestonTexas 77555
| | - Nemil Bhatt
- Mitchell Center for Neurodegenerative DiseasesUniversity of Texas Medical BranchGalvestonTexas 77555
- Department of NeurologyUniversity of Texas Medical BranchGalvestonTexas 77555
| | - Daniel V. Cantu
- Mitchell Center for Neurodegenerative DiseasesUniversity of Texas Medical BranchGalvestonTexas 77555
- Department of NeurologyUniversity of Texas Medical BranchGalvestonTexas 77555
| | - Marcos J. Guerrero‐Munoz
- Mitchell Center for Neurodegenerative DiseasesUniversity of Texas Medical BranchGalvestonTexas 77555
- Department of NeurologyUniversity of Texas Medical BranchGalvestonTexas 77555
| | - Anna Ellsworth
- Mitchell Center for Neurodegenerative DiseasesUniversity of Texas Medical BranchGalvestonTexas 77555
- Department of NeurologyUniversity of Texas Medical BranchGalvestonTexas 77555
| | - Urmi Sengupta
- Mitchell Center for Neurodegenerative DiseasesUniversity of Texas Medical BranchGalvestonTexas 77555
- Department of NeurologyUniversity of Texas Medical BranchGalvestonTexas 77555
| | - Rakez Kayed
- Mitchell Center for Neurodegenerative DiseasesUniversity of Texas Medical BranchGalvestonTexas 77555
- Department of NeurologyUniversity of Texas Medical BranchGalvestonTexas 77555
| |
Collapse
|
20
|
Yamaguchi KI, Kuwata K. Formation and properties of amyloid fibrils of prion protein. Biophys Rev 2018; 10:517-525. [PMID: 29204880 PMCID: PMC5899736 DOI: 10.1007/s12551-017-0377-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Accepted: 11/23/2017] [Indexed: 02/06/2023] Open
Abstract
Amyloid fibrils formed from prion protein (PrP) are associated with prion diseases. In this review we discuss a number of extrinsic and intrinsic experimental factors related to the formation of PrP amyloid fibrils in vitro. We first examined the effects of ultrasonic power on the induction of amyloid fibrillation from PrP. The most important conclusion drawn from the results is that an applied ultrasonic power of approximately 2 W enhanced the nucleation of amyloid fibrils efficiently but that more powerful ultrasonication led to retardation of growth. We also reviewed evidence on the amyloidogenic regions of PrP based on peptide screening throughout the polypeptide sequence. These results showed that helix 2 (H2) peptides of PrP were capable of both the fibrillation and propagation of straight, long fibrils. Moreover, the conformation of preformed H2 fibrils changed reversibly depending on the pH of the solution, implying that interactions between side-chains modulated the conformation of amyloid fibrils. The evidence discussed in this review relates specifically to PrP but may be relevant to other amyloidogenic proteins.
Collapse
Affiliation(s)
- Kei-ichi Yamaguchi
- Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565-0871 Japan
- United Graduate School of Drug Discovery and Medical Information Sciences, Gifu University, Yanagido 1-1, Gifu, 501-1193 Japan
| | - Kazuo Kuwata
- United Graduate School of Drug Discovery and Medical Information Sciences, Gifu University, Yanagido 1-1, Gifu, 501-1193 Japan
- Graduate School of Medicine, Gifu University, Yanagido 1-1, Gifu, 501-1193 Japan
| |
Collapse
|
21
|
Goto Y, Adachi M, Muta H, So M. Salt-induced formations of partially folded intermediates and amyloid fibrils suggests a common underlying mechanism. Biophys Rev 2017; 10:493-502. [PMID: 29256120 DOI: 10.1007/s12551-017-0370-7] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Accepted: 11/19/2017] [Indexed: 12/26/2022] Open
Abstract
Amyloid fibrils are misfolded forms of proteins and are involved in various diseases. They have been studied extensively with the aim to obtain a comprehensive understanding of protein folding and misfolding and to use this knowledge to develop therapeutic strategies against the associated diseases. Salt conditions are important factors determining the formation and stability of amyloid fibrils. In the 1990s, salt effects were studied extensively to understand the conformational stability of acid-denatured proteins, and the results of these studies revealed the role of electrostatic repulsion in forming the compact intermediate states. In this review, we compare the effects of salts on the compact intermediate states with those on the formation of amyloid fibrils under acidic conditions. The results argue that both protein folding and misfolding are driven by the same forces, although the resultant conformations are distinct because they are monomeric and multimeric reactions, respectively.
Collapse
Affiliation(s)
- Yuji Goto
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka, 565-0871, Japan.
| | - Masayuki Adachi
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka, 565-0871, Japan
| | - Hiroya Muta
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka, 565-0871, Japan
| | - Masatomo So
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka, 565-0871, Japan
| |
Collapse
|
22
|
Nitani A, Muta H, Adachi M, So M, Sasahara K, Sakurai K, Chatani E, Naoe K, Ogi H, Hall D, Goto Y. Heparin-dependent aggregation of hen egg white lysozyme reveals two distinct mechanisms of amyloid fibrillation. J Biol Chem 2017; 292:21219-21230. [PMID: 29101231 DOI: 10.1074/jbc.m117.813097] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Revised: 10/19/2017] [Indexed: 01/22/2023] Open
Abstract
Heparin, a biopolymer possessing high negative charge density, is known to accelerate amyloid fibrillation by various proteins. Using hen egg white lysozyme, we studied the effects of heparin on protein aggregation at low pH, raised temperature, and applied ultrasonic irradiation, conditions under which amyloid fibrillation was promoted. Heparin exhibited complex bimodal concentration-dependent effects, either accelerating or inhibiting fibrillation at pH 2.0 and 60 °C. At concentrations lower than 20 μg/ml, heparin accelerated fibrillation through transient formation of hetero-oligomeric aggregates. Between 0.1 and 10 mg/ml, heparin rapidly induced amorphous heteroaggregation with little to no accompanying fibril formation. Above 10 mg/ml, heparin again induced fibrillation after a long lag time preceded by oligomeric aggregate formation. Compared with studies performed using monovalent and divalent anions, the results suggest two distinct mechanisms of heparin-induced fibrillation. At low heparin concentrations, initial hen egg white lysozyme cluster formation and subsequent fibrillation is promoted by counter ion binding and screening of repulsive charges. At high heparin concentrations, fibrillation is caused by a combination of salting out and macromolecular crowding effects probably independent of protein net charge. Both fibrillation mechanisms compete against amorphous aggregation, producing a complex heparin concentration-dependent phase diagram. Moreover, the results suggest an active role for amorphous oligomeric aggregates in triggering fibrillation, whereby breakdown of supersaturation takes place through heterogeneous nucleation of amyloid on amorphous aggregates.
Collapse
Affiliation(s)
- Ayame Nitani
- From the Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan
| | - Hiroya Muta
- From the Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan
| | - Masayuki Adachi
- From the Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan
| | - Masatomo So
- From the Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan
| | - Kenji Sasahara
- From the Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan
| | - Kazumasa Sakurai
- Institute of Advanced Technology, Kindai University, 930 Nishimitani, Kinokawa, Wakayama 649-6493, Japan
| | - Eri Chatani
- Department of Chemistry, Graduate School of Science, Kobe University, Hyogo 657-8501, Japan
| | - Kazumitsu Naoe
- National Institute of Technology, Nara College, Nara 639-1080, Japan
| | - Hirotsugu Ogi
- Graduate School of Engineering, Suita, Osaka 565-0871, Japan, and
| | - Damien Hall
- From the Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan.,Research School of Chemistry, Australian National University, Acton, ACT 2601, Australia
| | - Yuji Goto
- From the Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan,
| |
Collapse
|
23
|
Yoshimura Y, Holmberg MA, Kukic P, Andersen CB, Mata-Cabana A, Falsone SF, Vendruscolo M, Nollen EAA, Mulder FAA. MOAG-4 promotes the aggregation of α-synuclein by competing with self-protective electrostatic interactions. J Biol Chem 2017; 292:8269-8278. [PMID: 28336532 DOI: 10.1074/jbc.m116.764886] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Revised: 03/01/2017] [Indexed: 11/06/2022] Open
Abstract
Aberrant protein aggregation underlies a variety of age-related neurodegenerative disorders, including Alzheimer's and Parkinson's diseases. Little is known, however, about the molecular mechanisms that modulate the aggregation process in the cellular environment. Recently, MOAG-4/SERF has been identified as a class of evolutionarily conserved proteins that positively regulates aggregate formation. Here, by using nuclear magnetic resonance (NMR) spectroscopy, we examine the mechanism of action of MOAG-4 by characterizing its interaction with α-synuclein (α-Syn). NMR chemical shift perturbations demonstrate that a positively charged segment of MOAG-4 forms a transiently populated α-helix that interacts with the negatively charged C terminus of α-Syn. This process interferes with the intramolecular interactions between the N- and C-terminal regions of α-Syn, resulting in the protein populating less compact forms and aggregating more readily. These results provide a compelling example of the complex competition between molecular and cellular factors that protect against protein aggregation and those that promote it.
Collapse
Affiliation(s)
- Yuichi Yoshimura
- Interdisciplinary Nanoscience Center (iNANO) and Department of Chemistry, Aarhus University, Gustav Wieds Vej 14, 8000 Aarhus C, Denmark
| | - Mats A Holmberg
- University of Groningen, University Medical Centre Groningen, European Research Institute for the Biology of Aging, 9700 AD Groningen, The Netherlands
| | - Predrag Kukic
- Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, United Kingdom
| | - Camilla B Andersen
- Interdisciplinary Nanoscience Center (iNANO) and Department of Molecular Biology and Genetics, Aarhus University, Gustav Wieds Vej 14, 8000 Aarhus C, Denmark
| | - Alejandro Mata-Cabana
- University of Groningen, University Medical Centre Groningen, European Research Institute for the Biology of Aging, 9700 AD Groningen, The Netherlands
| | - S Fabio Falsone
- Institute of Pharmaceutical Sciences, University of Graz, Schubertstr. 1, 8010 Graz, Austria
| | - Michele Vendruscolo
- Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, United Kingdom
| | - Ellen A A Nollen
- University of Groningen, University Medical Centre Groningen, European Research Institute for the Biology of Aging, 9700 AD Groningen, The Netherlands
| | - Frans A A Mulder
- Interdisciplinary Nanoscience Center (iNANO) and Department of Chemistry, Aarhus University, Gustav Wieds Vej 14, 8000 Aarhus C, Denmark.
| |
Collapse
|
24
|
Zhao R, So M, Maat H, Ray NJ, Arisaka F, Goto Y, Carver JA, Hall D. Measurement of amyloid formation by turbidity assay-seeing through the cloud. Biophys Rev 2016; 8:445-471. [PMID: 28003859 PMCID: PMC5135725 DOI: 10.1007/s12551-016-0233-7] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2016] [Accepted: 10/11/2016] [Indexed: 12/12/2022] Open
Abstract
Detection of amyloid growth is commonly carried out by measurement of solution turbidity, a low-cost assay procedure based on the intrinsic light scattering properties of the protein aggregate. Here, we review the biophysical chemistry associated with the turbidimetric assay methodology, exploring the reviewed literature using a series of pedagogical kinetic simulations. In turn, these simulations are used to interrogate the literature concerned with in vitro drug screening and the assessment of amyloid aggregation mechanisms.
Collapse
Affiliation(s)
- Ran Zhao
- Research School of Chemistry, Australian National University, Acton ACT, 2601, Australia
| | - Masatomo So
- Institute for Protein Research, Osaka University, 3-1- Yamada-oka, Suita, Osaka, 565-0871, Japan
| | - Hendrik Maat
- Research School of Chemistry, Australian National University, Acton ACT, 2601, Australia
| | - Nicholas J Ray
- Research School of Chemistry, Australian National University, Acton ACT, 2601, Australia
| | - Fumio Arisaka
- College of Bio-resource Sciences, Nihon University, Chiyoda-ku, Tokyo, 102-8275, Japan
| | - Yuji Goto
- Institute for Protein Research, Osaka University, 3-1- Yamada-oka, Suita, Osaka, 565-0871, Japan
| | - John A Carver
- Research School of Chemistry, Australian National University, Acton ACT, 2601, Australia
| | - Damien Hall
- Research School of Chemistry, Australian National University, Acton ACT, 2601, Australia. .,Institute for Protein Research, Osaka University, 3-1- Yamada-oka, Suita, Osaka, 565-0871, Japan.
| |
Collapse
|
25
|
Hall D, Zhao R, So M, Adachi M, Rivas G, Carver JA, Goto Y. Recognizing and analyzing variability in amyloid formation kinetics: Simulation and statistical methods. Anal Biochem 2016; 510:56-71. [PMID: 27430932 DOI: 10.1016/j.ab.2016.07.013] [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: 05/04/2016] [Revised: 07/11/2016] [Accepted: 07/13/2016] [Indexed: 12/24/2022]
Abstract
We examine the phenomenon of variability in the kinetics of amyloid formation and detail methods for its simulation, identification and analysis. Simulated data, reflecting intrinsic variability, were produced using rate constants, randomly sampled from a pre-defined distribution, as parameters in an irreversible nucleation-growth kinetic model. Simulated kinetic traces were reduced in complexity through description in terms of three characteristic parameters. Practical methods for assessing convergence of the reduced parameter distributions were introduced and a bootstrap procedure was applied to determine convergence for different levels of intrinsic variation. Statistical methods for assessing the significance of shifts in parameter distributions, relating to either change in parameter mean or distribution shape, were tested. Robust methods for analyzing and interpreting kinetic data possessing significant intrinsic variance will allow greater scrutiny of the effects of anti-amyloid compounds in drug trials.
Collapse
Affiliation(s)
- Damien Hall
- Research School of Chemistry, Australian National University, Acton ACT 2601, Australia; Institute for Protein Research, Osaka University, 3-1- Yamada-oka, Suita, Osaka 565-0871 Japan.
| | - Ran Zhao
- Research School of Chemistry, Australian National University, Acton ACT 2601, Australia
| | - Masatomo So
- Institute for Protein Research, Osaka University, 3-1- Yamada-oka, Suita, Osaka 565-0871 Japan
| | - Masayuki Adachi
- Institute for Protein Research, Osaka University, 3-1- Yamada-oka, Suita, Osaka 565-0871 Japan
| | - Germán Rivas
- Centro de Investigaciones Biológicas, CSIC, 28006 Madrid, Spain
| | - John A Carver
- Research School of Chemistry, Australian National University, Acton ACT 2601, Australia
| | - Yuji Goto
- Institute for Protein Research, Osaka University, 3-1- Yamada-oka, Suita, Osaka 565-0871 Japan
| |
Collapse
|
26
|
Noda S, So M, Adachi M, Kardos J, Akazawa-Ogawa Y, Hagihara Y, Goto Y. Thioflavin T-Silent Denaturation Intermediates Support the Main-Chain-Dominated Architecture of Amyloid Fibrils. Biochemistry 2016; 55:3937-48. [PMID: 27345358 DOI: 10.1021/acs.biochem.6b00231] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Ultrasonication is considered one of the most effective agitations for inducing the spontaneous formation of amyloid fibrils. When we induced the ultrasonication-dependent fibrillation of β2-microglobulin and insulin monitored by amyloid-specific thioflavin T (ThT) fluorescence, both proteins showed a significant decrease in ThT fluorescence after the burst-phase increase. The decrease in ThT fluorescence was accelerated when the ultrasonic power was stronger, suggesting that this decrease was caused by the partial denaturation of preformed fibrils. The possible intermediates of denaturation retained amyloid-like morphologies, secondary structures, and seeding potentials. Similar denaturation intermediates were also observed when fibrils were denatured by guanidine hydrochloride or sodium dodecyl sulfate. The presence of these denaturation intermediates is consistent with the main-chain-dominated architecture of amyloid fibrils. Moreover, in the three types of denaturation experiments conducted, insulin fibrils were more stable than β2-microglobulin fibrils, suggesting that the relative stability of various fibrils is independent of the method of denaturation.
Collapse
Affiliation(s)
- Sayaka Noda
- Institute for Protein Research, Osaka University , Yamadaoka 3-2, Suita, Osaka 565-0871, Japan
| | - Masatomo So
- Institute for Protein Research, Osaka University , Yamadaoka 3-2, Suita, Osaka 565-0871, Japan
| | - Masayuki Adachi
- Institute for Protein Research, Osaka University , Yamadaoka 3-2, Suita, Osaka 565-0871, Japan
| | - József Kardos
- Department of Biochemistry and MTA-ELTE NAP B Neuroimmunology Research Group, Eötvös Loránd University , Pázmány sétány 1/C, Budapest 1117, Hungary
| | - Yoko Akazawa-Ogawa
- National Institute of Advanced Industrial Science and Technology (AIST) , 1-8-31 Midorigaoka, Ikeda, Osaka 563-8577, Japan
| | - Yoshihisa Hagihara
- National Institute of Advanced Industrial Science and Technology (AIST) , 1-8-31 Midorigaoka, Ikeda, Osaka 563-8577, Japan
| | - Yuji Goto
- Institute for Protein Research, Osaka University , Yamadaoka 3-2, Suita, Osaka 565-0871, Japan
| |
Collapse
|
27
|
Prion 2016 Invited Lecture Abstracts. Prion 2016; 10 Suppl 1:S3-S14. [PMID: 27088810 DOI: 10.1080/19336896.2016.1163050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
|
28
|
Nakajima K, Ogi H, Adachi K, Noi K, Hirao M, Yagi H, Goto Y. Nucleus factory on cavitation bubble for amyloid β fibril. Sci Rep 2016; 6:22015. [PMID: 26912021 PMCID: PMC4766559 DOI: 10.1038/srep22015] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Accepted: 02/05/2016] [Indexed: 12/18/2022] Open
Abstract
Structural evolution from monomer to fibril of amyloid β peptide is related to pathogenic mechanism of Alzheimer disease, and its acceleration is a long-running problem in drug development. This study reveals that ultrasonic cavitation bubbles behave as catalysts for nucleation of the peptide: The nucleation reaction is highly dependent on frequency and pressure of acoustic wave, and we discover an optimum acoustical condition, at which the reaction-rate constant for nucleation is increased by three-orders-of magnitudes. A theoretical model is proposed for explaining highly frequency and pressure dependent nucleation reaction, where monomers are captured on the bubble surface during its growth and highly condensed by subsequent bubble collapse, so that they are transiently exposed to high temperatures. Thus, the dual effects of local condensation and local heating contribute to dramatically enhance the nucleation reaction. Our model consistently reproduces the frequency and pressure dependences, supporting its essential applicability.
Collapse
Affiliation(s)
- Kichitaro Nakajima
- Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
| | - Hirotsugu Ogi
- Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
| | - Kanta Adachi
- Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
| | - Kentaro Noi
- Institute of Molecular Embryology and Genetics, Kumamoto University, 2-2-1 Honjo, Chuo-ku, Kumamoto 860-0811, Japan
| | - Masahiko Hirao
- Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
| | - Hisashi Yagi
- Center for Reserch on Green Sustainable Chemistry, Tottori University, 4-101 Koyama-cho minami, Tottori, Tottori 680-8550, Japan
| | - Yuji Goto
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan
| |
Collapse
|
29
|
So M, Hall D, Goto Y. Revisiting supersaturation as a factor determining amyloid fibrillation. Curr Opin Struct Biol 2016; 36:32-9. [PMID: 26774801 DOI: 10.1016/j.sbi.2015.11.009] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 11/20/2015] [Indexed: 10/22/2022]
Abstract
Amyloid fibrils involved in various diseases are formed by a nucleation-growth mechanism, similar to the crystallization of solutes from solution. Solubility and supersaturation are two of the most important factors determining crystallization of solutes. Moreover, crystallization competes with glass formation in which solutes collapse into amorphous aggregates. Recent studies on the formation of amyloid fibrils and amorphous aggregates indicate that the partition between distinct types of aggregates can be rationally explained by a kinetic and thermodynamic competition between them. Understanding the role of supersaturation in determining aggregation-based phase transitions of denatured proteins provides an important complementary point of view to structural studies of protein aggregates.
Collapse
Affiliation(s)
- Masatomo So
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan
| | - Damien Hall
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan; Research School of Chemistry, Australian National University, Acton, ACT 2601, Australia
| | - Yuji Goto
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan.
| |
Collapse
|
30
|
Crespo R, Villar-Alvarez E, Taboada P, Rocha FA, Damas AM, Martins PM. What Can the Kinetics of Amyloid Fibril Formation Tell about Off-pathway Aggregation? J Biol Chem 2015; 291:2018-2032. [PMID: 26601940 DOI: 10.1074/jbc.m115.699348] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Indexed: 11/06/2022] Open
Abstract
Some of the most prevalent neurodegenerative diseases are characterized by the accumulation of amyloid fibrils in organs and tissues. Although the pathogenic role of these fibrils has not been completely established, increasing evidence suggests off-pathway aggregation as a source of toxic/detoxicating deposits that still remains to be targeted. The present work is a step toward the development of off-pathway modulators using the same amyloid-specific dyes as those conventionally employed to screen amyloid inhibitors. We identified a series of kinetic signatures revealing the quantitative importance of off-pathway aggregation relative to amyloid fibrillization; these include non-linear semilog plots of amyloid progress curves, highly variable end point signals, and half-life coordinates weakly influenced by concentration. Molecules that attenuate/intensify the magnitude of these signals are considered promising off-pathway inhibitors/promoters. An illustrative example shows that amyloid deposits of lysozyme are only the tip of an iceberg hiding a crowd of insoluble aggregates. Thoroughly validated using advanced microscopy techniques and complementary measurements of dynamic light scattering, CD, and soluble protein depletion, the new analytical tools are compatible with the high-throughput methods currently employed in drug discovery.
Collapse
Affiliation(s)
- Rosa Crespo
- From the Laboratório de Engenharia de Processos, Ambiente, Biotecnologia e Energia, Departamento de Engenharia Química, Faculdade de Engenharia da Universidade do Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
| | - Eva Villar-Alvarez
- the Departamento de Física de la Materia Condensada, Facultad de Física, Universidad de Santiago de Compostela, 15782 Spain, and
| | - Pablo Taboada
- the Departamento de Física de la Materia Condensada, Facultad de Física, Universidad de Santiago de Compostela, 15782 Spain, and
| | - Fernando A Rocha
- From the Laboratório de Engenharia de Processos, Ambiente, Biotecnologia e Energia, Departamento de Engenharia Química, Faculdade de Engenharia da Universidade do Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
| | - Ana M Damas
- the Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, 4050-313 Porto, Portugal
| | - Pedro M Martins
- From the Laboratório de Engenharia de Processos, Ambiente, Biotecnologia e Energia, Departamento de Engenharia Química, Faculdade de Engenharia da Universidade do Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal,; the Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, 4050-313 Porto, Portugal.
| |
Collapse
|
31
|
Oshita M, Yokoyama T, Takei Y, Takeuchi A, Ironside JW, Kitamoto T, Morita M. Efficient propagation of variant Creutzfeldt-Jakob disease prion protein using the cell-protein misfolding cyclic amplification technique with samples containing plasma and heparin. Transfusion 2015; 56:223-30. [PMID: 26347231 DOI: 10.1111/trf.13279] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Revised: 06/02/2015] [Accepted: 07/12/2015] [Indexed: 11/26/2022]
Abstract
BACKGROUND To prevent the iatrogenic spread of variant Creutzfeldt-Jakob disease (vCJD) between humans via blood products or transfusion, highly sensitive in vitro screening tests are necessary. Protein misfolding cyclic amplification (PMCA) is one such candidate test. However, plasma has been reported to inhibit the PMCA reaction. Therefore, we investigated the cell-PMCA conditions that permit vCJD prion amplification in the presence of plasma. STUDY DESIGN AND METHODS Cell-PMCA of vCJD samples was performed by adding various final concentrations of pooled plasma, citrate-phosphate-dextrose (CPD), albumin, globulin, or pooled plasma treated with ion exchangers. After heparin and plasma concentrations were optimized, multiround cell-PMCA was performed. RESULTS When 1% to 50% of pooled plasma was added to heparinized cell-PMCA, amplification efficiency showed a double-peaked profile at less than 1% and 40% final plasma concentrations, indicating that plasma contains not only PMCA inhibitors but also promoters. Intravenous globulin did not inhibit cell-PMCA, but the protein G-bound fraction did. CPD, albumin-depleted plasma, and the unbound fraction of anion-exchange chromatography inhibited cell-PMCA, but albumin and the unbound fraction of the cation-exchange chromatography did not. The detection limit of abnormal prion protein in multiround cell-PMCA, when maintaining the final plasma concentration at 40% at each round, was 10(-10) dilutions of a vCJD brain specimen. CONCLUSION We have established a novel cell-PMCA format in the presence of plasma without any pretreatment, where vCJD prion protein was amplified at comparable levels to that found without plasma. Our data suggest the feasibility of cell-PMCA as a practical blood test for vCJD prions.
Collapse
Affiliation(s)
- Masatoshi Oshita
- Research and Development Division, Japan Blood Products Organization, Tokyo, Japan
| | - Takashi Yokoyama
- Research and Development Division, Japan Blood Products Organization, Tokyo, Japan
| | - Yumiko Takei
- Research and Development Division, Japan Blood Products Organization, Tokyo, Japan
| | - Atsuko Takeuchi
- Department of Neurological Science, Tohoku University Graduate School of Medicine, Sendai, Miyagi Prefecture, Japan
| | - James W Ironside
- National CJD Research and Surveillance Unit, Centre for Clinical Brain Sciences, University of Edinburgh, Western General Hospital, Edinburgh, United Kingdom
| | - Tetsuyuki Kitamoto
- Department of Neurological Science, Tohoku University Graduate School of Medicine, Sendai, Miyagi Prefecture, Japan
| | - Masanori Morita
- Research and Development Division, Japan Blood Products Organization, Tokyo, Japan
| |
Collapse
|
32
|
Adachi M, So M, Sakurai K, Kardos J, Goto Y. Supersaturation-limited and Unlimited Phase Transitions Compete to Produce the Pathway Complexity in Amyloid Fibrillation. J Biol Chem 2015; 290:18134-18145. [PMID: 26063798 DOI: 10.1074/jbc.m115.648139] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2015] [Indexed: 01/16/2023] Open
Abstract
Although amyloid fibrils and amorphous aggregates are two types of aggregates formed by denatured proteins, their relationship currently remains unclear. We used β2-microglobulin (β2m), a protein responsible for dialysis-related amyloidosis, to clarify the mechanism by which proteins form either amyloid fibrils or amorphous aggregates. When ultrasonication was used to accelerate the spontaneous fibrillation of β2m at pH 2.0, the effects observed depended on ultrasonic power; although stronger ultrasonic power effectively accelerated fibrillation, excessively strong ultrasonic power decreased the amount of fibrils formed, as monitored by thioflavin T fluorescence. An analysis of the products formed indicated that excessively strong ultrasonic power generated fibrillar aggregates that retained β-structures but without high efficiency as seeds. On the other hand, when the spontaneous fibrillation of β2m was induced at higher concentrations of NaCl at pH 2.0 with stirring, amorphous aggregates became more dominant than amyloid fibrils. These apparent complexities in fibrillation were explained comprehensively by a competitive mechanism in which supersaturation-limited reactions competed with supersaturation-unlimited reactions. We link the kinetics of protein aggregation and a conformational phase diagram, in which supersaturation played important roles.
Collapse
Affiliation(s)
- Masayuki Adachi
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan
| | - Masatomo So
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan
| | - Kazumasa Sakurai
- High Pressure Protein Research Center, Institute for Advanced Technology, Kinki University, 930 Nishimitani, Kinokawa, Wakayama 649-6493, Japan
| | - József Kardos
- Department of Biochemistry and MTA-ELTE NAP B Neuroimmunology Research Group, Eötvös Loránd University, Pázmány sétány 1/C, Budapest, 1117, Hungary
| | - Yuji Goto
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan.
| |
Collapse
|
33
|
Ciryam P, Kundra R, Morimoto RI, Dobson CM, Vendruscolo M. Supersaturation is a major driving force for protein aggregation in neurodegenerative diseases. Trends Pharmacol Sci 2015; 36:72-7. [PMID: 25636813 PMCID: PMC4643722 DOI: 10.1016/j.tips.2014.12.004] [Citation(s) in RCA: 123] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2014] [Revised: 12/05/2014] [Accepted: 12/08/2014] [Indexed: 01/29/2023]
Abstract
The solubility of proteins is an essential requirement for their function. Nevertheless, these ubiquitous molecules can undergo aberrant aggregation when the protein homeostasis system becomes impaired. Here we ask: what are the driving forces for protein aggregation in the cellular environment? Emerging evidence suggests that this phenomenon arises at least in part because the native states of many proteins are inherently metastable when their cellular concentrations exceed their critical values. Such 'supersaturated' proteins, which form a 'metastable subproteome', are strongly driven towards aggregation, and are over-represented in specific biochemical pathways associated with neurodegenerative conditions. These observations suggest that effective therapeutic approaches designed to combat neurodegenerative diseases could be aimed at enhancing the ability of the cell to maintain the homeostasis of the metastable subproteome.
Collapse
Affiliation(s)
- Prajwal Ciryam
- Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK; Department of Molecular Biosciences, Rice Institute for Biomedical Research, Northwestern University, Evanston, IL 60208, USA
| | - Rishika Kundra
- Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK
| | - Richard I Morimoto
- Department of Molecular Biosciences, Rice Institute for Biomedical Research, Northwestern University, Evanston, IL 60208, USA
| | | | | |
Collapse
|
34
|
Yagi H, Mizuno A, So M, Hirano M, Adachi M, Akazawa-Ogawa Y, Hagihara Y, Ikenoue T, Lee YH, Kawata Y, Goto Y. Ultrasonication-dependent formation and degradation of α-synuclein amyloid fibrils. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2014; 1854:209-17. [PMID: 25528988 DOI: 10.1016/j.bbapap.2014.12.014] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2014] [Revised: 12/04/2014] [Accepted: 12/12/2014] [Indexed: 01/15/2023]
Abstract
Ultrasonication can be used to break the supersaturation of α-synuclein, a protein associated with Parkinson's disease, at pH7.4 above the critical concentration of fibrillation, thereby inducing the formation of amyloid fibrils. We speculated that ultrasonication could also be used to depolymerize preformed fibrils below the critical concentration. However, extensive ultrasonic irradiation transformed preformed fibrils into amorphous aggregates even above the critical concentration. Exposing preformed fibrils to the hydrophobic air-water interface of cavitation bubbles may have destabilized the fibrils and stabilized amorphous aggregates. Upon extensive ultrasonic irradiation, the accompanying decomposition of chemical structures was suggested when monitored by analytical ultracentrifugation. Amorphous aggregates produced by extensive ultrasonication showed higher cytotoxicity, suggesting that, although ultrasonication might be a useful approach for inactivating amyloid fibrils, potential cytotoxicity of amorphous aggregates should be considered.
Collapse
Affiliation(s)
- Hisashi Yagi
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan; Center for Research on Green Sustainable Chemistry, Tottori University, Tottori 680-8552, Japan
| | - Aiko Mizuno
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan
| | - Masatomo So
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan
| | - Miki Hirano
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan
| | - Masayuki Adachi
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan
| | - Yoko Akazawa-Ogawa
- National Institute of Advanced Industrial Science and Technology (AIST), 1-8-31 Midorigaoka, Ikeda, Osaka 563-8577, Japan
| | - Yoshihisa Hagihara
- National Institute of Advanced Industrial Science and Technology (AIST), 1-8-31 Midorigaoka, Ikeda, Osaka 563-8577, Japan
| | - Tatsuya Ikenoue
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan
| | - Young-Ho Lee
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan
| | - Yasushi Kawata
- Department of Chemistry and Biotechnology, Graduate School of Engineering, Tottori University, Tottori 680-8552, Japan
| | - Yuji Goto
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan.
| |
Collapse
|