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Lin H, Sandkuhler S, Dunlea C, Rodwell-Bullock J, King DH, Johnson GVW. BAG3 regulates the specificity of the recognition of specific MAPT species by NBR1 and SQSTM1. Autophagy 2024; 20:577-589. [PMID: 37899687 PMCID: PMC10936643 DOI: 10.1080/15548627.2023.2276622] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Accepted: 10/19/2023] [Indexed: 10/31/2023] Open
Abstract
Macroautophagy/autophagy receptors are essential for the recognition and clearance of specific cargos by selective autophagy, which is essential for maintaining MAPT proteostasis. Previous studies have implicated different autophagy receptors in directing distinct species of MAPT to autophagy, but the underlying mechanisms have not been fully investigated. Here we examine how the autophagy receptors NBR1 and SQSTM1 differentially associate with specific forms of MAPT. In primary neurons depletion of NBR1, unlike depletion of SQSTM1, significantly increased phosphorylated MAPT levels. The specificity of the interactions was confirmed using in vitro binding assays with purified proteins. We provide direct evidence that the co-chaperone BAG3 promotes the preferential association of NBR1 with monomeric MAPT and SQSTM1 with oligomeric MAPT. Using an in vitro affinity-isolation assay, we show that SQSTM1 only binds to monomeric MAPT when BAG3 is absent and fails to bind when BAG3 is present. The opposite is true of NBR1; its association with monomeric MAPT was dependent on the presence of BAG3. Interestingly, in Alzheimer disease brain the association of NBR1 with BAG3 was significantly decreased. In a mouse model, ablation of BAG3 in neural cells disrupted the association of NBR1 with phosphorylated MAPT and led to increased levels of phosphorylated and oligomeric MAPT. Overall, our results uncover a novel role for BAG3 in regulating the specificity of selective autophagy receptors in targeting different species of MAPT and provide compelling evidence that BAG3 plays a key role in maintaining MAPT proteostasis.Abbreviations: AD: Alzheimer disease; BAG3: BCL2-associated athanogene 3; BSA: bovine serum albumin; CERAD: Consortium to Establish a Registry for Alzheimer's Disease; ESCRT: endosomal sorting complexes required for transport; GST: glutathione S-transferases; MAPT: microtubule-associated protein tau; NBR1: NBR1, autophagy cargo receptor; NFT: neurofibrillary tangles; PMI: postmortem interval; SQSTM1: sequestosome 1.
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Affiliation(s)
- Heng Lin
- Department of Anesthesiology and Perioperative Medicine, University of Rochester, Rochester, NY, USA
| | - Sarah Sandkuhler
- Department of Anesthesiology and Perioperative Medicine, University of Rochester, Rochester, NY, USA
| | - Colleen Dunlea
- Department of Anesthesiology and Perioperative Medicine, University of Rochester, Rochester, NY, USA
| | - Joel Rodwell-Bullock
- Department of Anesthesiology and Perioperative Medicine, University of Rochester, Rochester, NY, USA
| | - Darron H King
- Department of Anesthesiology and Perioperative Medicine, University of Rochester, Rochester, NY, USA
| | - Gail V. W. Johnson
- Department of Anesthesiology and Perioperative Medicine, University of Rochester, Rochester, NY, USA
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2
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Esquivel AR, Hill SE, Blair LJ. DnaJs are enriched in tau regulators. Int J Biol Macromol 2023; 253:127486. [PMID: 37852393 PMCID: PMC10842427 DOI: 10.1016/j.ijbiomac.2023.127486] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Revised: 10/09/2023] [Accepted: 10/15/2023] [Indexed: 10/20/2023]
Abstract
The aberrant accumulation of tau protein is implicated as a pathogenic factor in many neurodegenerative diseases. Tau seeding may underlie its predictable spread in these diseases. Molecular chaperones can modulate tau pathology, but their effects have mainly been studied in isolation. This study employed a semi-high throughput assay to identify molecular chaperones influencing tau seeding using Tau RD P301S FRET Biosensor cells, which express a portion of tau containing the frontotemporal dementia-related P301S tau mutation fused to a FRET biosensor. Approximately fifty chaperones from five major families were screened using live cell imaging to monitor FRET-positive tau seeding. Among the tested chaperones, five exhibited significant effects on tau in the primary screen. Notably, three of these were from the DnaJ family. In subsequent studies, overexpression of DnaJA2, DnaJB1, and DnaJB6b resulted in significant reductions in tau levels. Knockdown experiments by shRNA revealed an inverse correlation between DnaJB1 and DnaJB6b with tau levels. DnaJB6b overexpression, specifically, reduced total tau levels in a cellular model with a pre-existing pool of tau, partially through enhanced proteasomal degradation. Further, DnaJB6b interacted with tau complexes. These findings highlight the potent chaperone activity within the DnaJ family, particularly DnaJB6b, towards tau.
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Affiliation(s)
- Abigail R Esquivel
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA; USF Health Byrd Alzheimer's Institute, University of South Florida, Tampa, FL 33613, USA
| | - Shannon E Hill
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA; USF Health Byrd Alzheimer's Institute, University of South Florida, Tampa, FL 33613, USA
| | - Laura J Blair
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA; USF Health Byrd Alzheimer's Institute, University of South Florida, Tampa, FL 33613, USA; Research Service, James A Haley Veterans Hospital, 13000 Bruce B Downs Blvd, Tampa, FL 33612, USA.
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3
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Chang YL, Yang CC, Huang YY, Chen YA, Yang CW, Liao CY, Li H, Wu CS, Lin CH, Teng SC. The HSP40 family chaperone isoform DNAJB6b prevents neuronal cells from tau aggregation. BMC Biol 2023; 21:293. [PMID: 38110916 PMCID: PMC10729500 DOI: 10.1186/s12915-023-01798-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Accepted: 12/05/2023] [Indexed: 12/20/2023] Open
Abstract
BACKGROUND Alzheimer's disease (AD) is the most common neurodegenerative disorder with clinical presentations of progressive cognitive and memory deterioration. The pathologic hallmarks of AD include tau neurofibrillary tangles and amyloid plaque depositions in the hippocampus and associated neocortex. The neuronal aggregated tau observed in AD cells suggests that the protein folding problem is a major cause of AD. J-domain-containing proteins (JDPs) are the largest family of cochaperones, which play a vital role in specifying and directing HSP70 chaperone functions. JDPs bind substrates and deliver them to HSP70. The association of JDP and HSP70 opens the substrate-binding domain of HSP70 to help the loading of the clients. However, in the initial HSP70 cycle, which JDP delivers tau to the HSP70 system in neuronal cells remains unclear. RESULTS We screened the requirement of a diverse panel of JDPs for preventing tau aggregation in the human neuroblastoma cell line SH-SY5Y by a filter retardation method. Interestingly, knockdown of DNAJB6, one of the JDPs, displayed tau aggregation and overexpression of DNAJB6b, one of the isoforms generated from the DNAJB6 gene by alternative splicing, reduced tau aggregation. Further, the tau bimolecular fluorescence complementation assay confirmed the DNAJB6b-dependent tau clearance. The co-immunoprecipitation and the proximity ligation assay demonstrated the protein-protein interaction between tau and the chaperone-cochaperone complex. The J-domain of DNAJB6b was critical for preventing tau aggregation. Moreover, reduced DNAJB6 expression and increased tau aggregation were detected in an age-dependent manner in immunohistochemical analysis of the hippocampus tissues of a mouse model of tau pathology. CONCLUSIONS In summary, downregulation of DNAJB6b increases the insoluble form of tau, while overexpression of DNAJB6b reduces tau aggregation. Moreover, DNAJB6b associates with tau. Therefore, this study reveals that DNAJB6b is a direct sensor for its client tau in the HSP70 folding system in neuronal cells, thus helping to prevent AD.
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Affiliation(s)
- Ya-Lan Chang
- Department of Microbiology, College of Medicine, National Taiwan University, No. 1, Section 1, Jen-Ai Road, Taipei, 10051, Taiwan
| | - Chan-Chih Yang
- Department of Microbiology, College of Medicine, National Taiwan University, No. 1, Section 1, Jen-Ai Road, Taipei, 10051, Taiwan
| | - Yun-Yu Huang
- Department of Microbiology, College of Medicine, National Taiwan University, No. 1, Section 1, Jen-Ai Road, Taipei, 10051, Taiwan
| | - Yi-An Chen
- Department of Microbiology, College of Medicine, National Taiwan University, No. 1, Section 1, Jen-Ai Road, Taipei, 10051, Taiwan
| | - Chia-Wei Yang
- Department of Microbiology, College of Medicine, National Taiwan University, No. 1, Section 1, Jen-Ai Road, Taipei, 10051, Taiwan
| | - Chia-Yu Liao
- Department of Microbiology, College of Medicine, National Taiwan University, No. 1, Section 1, Jen-Ai Road, Taipei, 10051, Taiwan
| | - Hsun Li
- Department of Neurology, National Taiwan University Hospital, No. 7, Chung-Shan South Road, Taipei, 10051, Taiwan
| | - Ching-Shyi Wu
- Department of Pharmacology, College of Medicine, National Taiwan University, Taipei, 10051, Taiwan
| | - Chin-Hsien Lin
- Department of Neurology, National Taiwan University Hospital, No. 7, Chung-Shan South Road, Taipei, 10051, Taiwan.
| | - Shu-Chun Teng
- Department of Microbiology, College of Medicine, National Taiwan University, No. 1, Section 1, Jen-Ai Road, Taipei, 10051, Taiwan.
- Center of Precision Medicine, National Taiwan University, Taipei, 10051, Taiwan.
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4
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Jahreis K, Brüge A, Borsdorf S, Müller FE, Sun W, Jia S, Kang DM, Boesen N, Shin S, Lim S, Koroleva A, Satała G, Bojarski AJ, Rakuša E, Fink A, Doblhammer-Reiter G, Kim YK, Dityatev A, Ponimaskin E, Labus J. Amisulpride as a potential disease-modifying drug in the treatment of tauopathies. Alzheimers Dement 2023; 19:5482-5497. [PMID: 37218673 DOI: 10.1002/alz.13090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 03/07/2023] [Accepted: 03/08/2023] [Indexed: 05/24/2023]
Abstract
INTRODUCTION Hyperphosphorylation and aggregation of the microtubule-associated protein tau cause the development of tauopathies, such as Alzheimer's disease and frontotemporal dementia (FTD). We recently uncovered a causal link between constitutive serotonin receptor 7 (5-HT7R) activity and pathological tau aggregation. Here, we evaluated 5-HT7R inverse agonists as novel drugs in the treatment of tauopathies. METHODS Based on structural homology, we screened multiple approved drugs for their inverse agonism toward 5-HT7R. Therapeutic potential was validated using biochemical, pharmacological, microscopic, and behavioral approaches in different cellular models including tau aggregation cell line HEK293 tau bimolecular fluorescence complementation, primary mouse neurons, and human induced pluripotent stem cell-derived neurons carrying an FTD-associated tau mutation as well as in two mouse models of tauopathy. RESULTS Antipsychotic drug amisulpride is a potent 5-HT7R inverse agonist. Amisulpride ameliorated tau hyperphosphorylation and aggregation in vitro. It further reduced tau pathology and abrogated memory impairment in mice. DISCUSSION Amisulpride may be a disease-modifying drug for tauopathies.
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Affiliation(s)
- Kathrin Jahreis
- Department of Cellular Neurophysiology, Hannover Medical School, Hannover, Germany
| | - Alina Brüge
- Department of Cellular Neurophysiology, Hannover Medical School, Hannover, Germany
| | - Saskia Borsdorf
- Department of Cellular Neurophysiology, Hannover Medical School, Hannover, Germany
| | - Franziska E Müller
- Department of Cellular Neurophysiology, Hannover Medical School, Hannover, Germany
| | - Weilun Sun
- German Center for Neurodegenerative Diseases (DZNE), Magdeburg, Germany
| | - Shaobo Jia
- German Center for Neurodegenerative Diseases (DZNE), Magdeburg, Germany
| | - Dong Min Kang
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, Republic of Korea
- Department of Life Sciences, Korea University, Seoul, Republic of Korea
| | - Nicolette Boesen
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, Republic of Korea
- Division of Bio-Medical Science & Technology, KIST School, Korea University of Science and Technology (UST), Seoul, Republic of Korea
| | - Seulgi Shin
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, Republic of Korea
| | - Sungsu Lim
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, Republic of Korea
| | - Anastasia Koroleva
- Department of Nanoengineering, Institute of Quantum Optics, Leibniz University Hannover, Hannover, Germany
| | - Grzegorz Satała
- Maj Institute of Pharmacology, Polish Academy of Sciences, Krakow, Poland
| | - Andrzej J Bojarski
- Maj Institute of Pharmacology, Polish Academy of Sciences, Krakow, Poland
| | - Elena Rakuša
- German Center for Neurodegenerative Diseases (DZNE), Rostock, Germany
| | - Anne Fink
- German Center for Neurodegenerative Diseases (DZNE), Rostock, Germany
| | | | - Yun Kyung Kim
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, Republic of Korea
- Maj Institute of Pharmacology, Polish Academy of Sciences, Krakow, Poland
| | - Alexander Dityatev
- German Center for Neurodegenerative Diseases (DZNE), Magdeburg, Germany
- Medical Faculty, Otto-von-Guericke University, Magdeburg, Germany
- Center for Behavioral Brain Sciences (CBBS), Magdeburg, Germany
| | - Evgeni Ponimaskin
- Department of Cellular Neurophysiology, Hannover Medical School, Hannover, Germany
| | - Josephine Labus
- Department of Cellular Neurophysiology, Hannover Medical School, Hannover, Germany
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5
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Ahn S, Suh JS, Jang YK, Kim H, Han K, Lee Y, Choi G, Kim TJ. TAUCON and TAUCOM: A novel biosensor based on fluorescence resonance energy transfer for detecting tau hyperphosphorylation-associated cellular pathologies. Biosens Bioelectron 2023; 237:115533. [PMID: 37517333 DOI: 10.1016/j.bios.2023.115533] [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: 05/02/2023] [Revised: 07/02/2023] [Accepted: 07/12/2023] [Indexed: 08/01/2023]
Abstract
Tauopathies are neurodegenerative diseases characterized by abnormal conformational changes in tau protein. Early hyperphosphorylation-induced conformational changes are considered a hallmark of tauopathy, but real-time tracking methods are lacking. Here, we present two novel fluorescence resonance energy transfer (FRET)-based tau biosensors that detect such changes with high spatiotemporal resolution at the single-cell level. The TAUCON biosensor measures instantaneous conformational changes in hyperphosphorylated tau within 20 min, while the TAUCOM biosensor detects changes in the paper-clip structure of microtubule-associated tau. Our biosensors provide faster and more precise detection than conventional methods and can serve as valuable tools for investigating the initial causes, mechanisms, progression, and treatment of tauopathies.
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Affiliation(s)
- Sanghyun Ahn
- Department of Integrated Biological Science, College of Natural Sciences, Pusan National University, Pusan, 46241, Republic of Korea
| | - Jung-Soo Suh
- Department of Integrated Biological Science, College of Natural Sciences, Pusan National University, Pusan, 46241, Republic of Korea
| | - Yoon-Kwan Jang
- Department of Integrated Biological Science, College of Natural Sciences, Pusan National University, Pusan, 46241, Republic of Korea
| | - Heonsu Kim
- Department of Integrated Biological Science, College of Natural Sciences, Pusan National University, Pusan, 46241, Republic of Korea
| | - Kiseok Han
- Department of Integrated Biological Science, College of Natural Sciences, Pusan National University, Pusan, 46241, Republic of Korea
| | - Yerim Lee
- Department of Integrated Biological Science, College of Natural Sciences, Pusan National University, Pusan, 46241, Republic of Korea
| | - Gyuho Choi
- Department of Integrated Biological Science, College of Natural Sciences, Pusan National University, Pusan, 46241, Republic of Korea
| | - Tae-Jin Kim
- Department of Integrated Biological Science, College of Natural Sciences, Pusan National University, Pusan, 46241, Republic of Korea; Department of Biological Sciences, College of Natural Sciences, Pusan National University, Pusan, 46241, Republic of Korea; Institute of System Biology, Pusan National University, Pusan, 46241, Republic of Korea.
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6
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Zhang ZY, Harischandra DS, Wang R, Ghaisas S, Zhao JY, McMonagle TP, Zhu G, Lacuarta KD, Song J, Trojanowski JQ, Xu H, Lee VMY, Yang X. TRIM11 protects against tauopathies and is down-regulated in Alzheimer's disease. Science 2023; 381:eadd6696. [PMID: 37499037 DOI: 10.1126/science.add6696] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2022] [Accepted: 06/01/2023] [Indexed: 07/29/2023]
Abstract
Aggregation of tau into filamentous inclusions underlies Alzheimer's disease (AD) and numerous other neurodegenerative tauopathies. The pathogenesis of tauopathies remains unclear, which impedes the development of disease-modifying treatments. Here, by systematically analyzing human tripartite motif (TRIM) proteins, we identified a few TRIMs that could potently inhibit tau aggregation. Among them, TRIM11 was markedly down-regulated in AD brains. TRIM11 promoted the proteasomal degradation of mutant tau as well as superfluous normal tau. It also enhanced tau solubility by acting as both a molecular chaperone to prevent tau misfolding and a disaggregase to dissolve preformed tau fibrils. TRIM11 maintained the connectivity and viability of neurons. Intracranial delivery of TRIM11 through adeno-associated viruses ameliorated pathology, neuroinflammation, and cognitive impairments in multiple animal models of tauopathies. These results suggest that TRIM11 down-regulation contributes to the pathogenesis of tauopathies and that restoring TRIM11 expression may represent an effective therapeutic strategy.
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Affiliation(s)
- Zi-Yang Zhang
- Department of Cancer Biology and Abramson Family Cancer Research Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Dilshan S Harischandra
- Department of Cancer Biology and Abramson Family Cancer Research Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Ruifang Wang
- Department of Cancer Biology and Abramson Family Cancer Research Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Shivani Ghaisas
- Department of Cancer Biology and Abramson Family Cancer Research Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Janet Y Zhao
- Department of Cancer Biology and Abramson Family Cancer Research Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Thomas P McMonagle
- Department of Cancer Biology and Abramson Family Cancer Research Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Guixin Zhu
- Department of Cancer Biology and Abramson Family Cancer Research Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Kenzo D Lacuarta
- Department of Cancer Biology and Abramson Family Cancer Research Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Jianing Song
- Department of Cancer Biology and Abramson Family Cancer Research Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - John Q Trojanowski
- Department of Pathology and Laboratory Medicine, Institute on Aging, and Center for Neurodegenerative Disease Research, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Hong Xu
- Department of Pathology and Laboratory Medicine, Institute on Aging, and Center for Neurodegenerative Disease Research, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Virginia M-Y Lee
- Department of Pathology and Laboratory Medicine, Institute on Aging, and Center for Neurodegenerative Disease Research, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Xiaolu Yang
- Department of Cancer Biology and Abramson Family Cancer Research Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
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7
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Cecon E, Oishi A, Luka M, Ndiaye-Lobry D, François A, Lescuyer M, Panayi F, Dam J, Machado P, Jockers R. Novel repertoire of tau biosensors to monitor pathological tau transformation and seeding activity in living cells. eLife 2023; 12:78360. [PMID: 36917493 PMCID: PMC10014071 DOI: 10.7554/elife.78360] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Accepted: 02/26/2023] [Indexed: 03/12/2023] Open
Abstract
Aggregates of the tau protein are a well-known hallmark of several neurodegenerative diseases, collectively referred to as tauopathies, including frontal temporal dementia and Alzheimer's disease (AD). Monitoring the transformation process of tau from physiological monomers into pathological oligomers or aggregates in a high-throughput, quantitative manner and in a cellular context is still a major challenge in the field. Identifying molecules able to interfere with those processes is of high therapeutic interest. Here, we developed a series of inter- and intramolecular tau biosensors based on the highly sensitive Nanoluciferase (Nluc) binary technology (NanoBiT) able to monitor the pathological conformational change and self-interaction of tau in living cells. Our repertoire of tau biosensors reliably reports i. molecular proximity of physiological full-length tau at microtubules; ii. changes in tau conformation and self-interaction associated with tau phosphorylation, as well as iii. tau interaction induced by seeds of recombinant tau or from mouse brain lysates of a mouse model of tau pathology. By comparing biosensors comprising different tau forms (i.e. full-length or short fragments, wild-type, or the disease-associated tau(P301L) variant) further insights into the tau transformation process are obtained. Proof-of-concept data for the high-throughput suitability and identification of molecules interfering with the pathological tau transformation processes are presented. This novel repertoire of tau biosensors is aimed to boost the disclosure of molecular mechanisms underlying pathological tau transformation in living cells and to discover new drug candidates for tau-related neurodegenerative diseases.
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Affiliation(s)
- Erika Cecon
- Institut Cochin, Inserm U1016, CNRS UMR 8104, Université de ParisParisFrance
| | - Atsuro Oishi
- Institut Cochin, Inserm U1016, CNRS UMR 8104, Université de ParisParisFrance
| | - Marine Luka
- Institut Cochin, Inserm U1016, CNRS UMR 8104, Université de ParisParisFrance
| | | | | | - Mathias Lescuyer
- Institut Cochin, Inserm U1016, CNRS UMR 8104, Université de ParisParisFrance
| | | | - Julie Dam
- Institut Cochin, Inserm U1016, CNRS UMR 8104, Université de ParisParisFrance
| | | | - Ralf Jockers
- Institut Cochin, Inserm U1016, CNRS UMR 8104, Université de ParisParisFrance
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8
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Lim S, Shin S, Sung Y, Lee HE, Kim KH, Song JY, Lee GH, Aziz H, Lukianenko N, Kang DM, Boesen N, Jeong H, Abdildinova A, Lee J, Yu BY, Lim SM, Lee JS, Ryu H, Pae AN, Kim YK. Levosimendan inhibits disulfide tau oligomerization and ameliorates tau pathology in Tau P301L-BiFC mice. Exp Mol Med 2023; 55:612-627. [PMID: 36914856 PMCID: PMC10073126 DOI: 10.1038/s12276-023-00959-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Revised: 12/26/2022] [Accepted: 01/01/2023] [Indexed: 03/14/2023] Open
Abstract
Tau oligomers play critical roles in tau pathology and are responsible for neuronal cell death and transmitting the disease in the brain. Accordingly, preventing tau oligomerization has become an important therapeutic strategy to treat tauopathies, including Alzheimer's disease. However, progress has been slow because detecting tau oligomers in the cellular context is difficult. Working toward tau-targeted drug discovery, our group has developed a tau-BiFC platform to monitor and quantify tau oligomerization. By using the tau-BiFC platform, we screened libraries with FDA-approved and passed phase I drugs and identified levosimendan as a potent anti-tau agent that inhibits tau oligomerization. 14C-isotope labeling of levosimendan revealed that levosimendan covalently bound to tau cysteines, directly inhibiting disulfide-linked tau oligomerization. In addition, levosimendan disassembles tau oligomers into monomers, rescuing neurons from aggregation states. In comparison, the well-known anti-tau agents methylene blue and LMTM failed to protect neurons from tau-mediated toxicity, generating high-molecular-weight tau oligomers. Levosimendan displayed robust potency against tau oligomerization and rescued cognitive declines induced by tauopathy in the TauP301L-BiFC mouse model. Our data present the potential of levosimendan as a disease-modifying drug for tauopathies.
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Affiliation(s)
- Sungsu Lim
- Center for Brain Disorders, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
| | - Seulgi Shin
- Center for Brain Disorders, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
| | - Yoonsik Sung
- Center for Brain Disorders, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea.,Division of Bio-Medical Science & Technology, KIST School, Korea University of Science and Technology (UST), Seoul, 02792, Republic of Korea
| | - Ha Eun Lee
- Center for Brain Disorders, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
| | - Kyu Hyeon Kim
- Center for Brain Disorders, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea.,Division of Bio-Medical Science & Technology, KIST School, Korea University of Science and Technology (UST), Seoul, 02792, Republic of Korea
| | - Ji Yeon Song
- Center for Brain Disorders, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
| | - Gwan-Ho Lee
- Advanced Analysis Center, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
| | - Hira Aziz
- Center for Brain Disorders, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea.,Division of Bio-Medical Science & Technology, KIST School, Korea University of Science and Technology (UST), Seoul, 02792, Republic of Korea
| | - Nataliia Lukianenko
- Center for Brain Disorders, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea.,Division of Bio-Medical Science & Technology, KIST School, Korea University of Science and Technology (UST), Seoul, 02792, Republic of Korea
| | - Dong Min Kang
- Center for Brain Disorders, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea.,Department of Life Sciences, Korea University, Seoul, 02841, Korea
| | - Nicolette Boesen
- Center for Brain Disorders, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea.,Division of Bio-Medical Science & Technology, KIST School, Korea University of Science and Technology (UST), Seoul, 02792, Republic of Korea
| | - Hyeanjeong Jeong
- Center for Brain Disorders, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
| | - Aizhan Abdildinova
- Center for Brain Disorders, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
| | - Junghee Lee
- Boston University Alzheimer's disease Research Center and VA Boston Health care System, Boston, MA, 02130, USA
| | - Byung-Yong Yu
- Advanced Analysis Center, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
| | - Sang Min Lim
- Center for Brain Disorders, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
| | - Jun-Seok Lee
- Department of Pharmacology, Korea University College of Medicine, Seoul, 02792, Republic of Korea
| | - Hoon Ryu
- Center for Brain Disorders, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea.,Boston University Alzheimer's disease Research Center and Department of Neurology, Boston University School of Medicine, Boston, MA, 02118, USA
| | - Ae Nim Pae
- Center for Brain Disorders, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea.
| | - Yun Kyung Kim
- Center for Brain Disorders, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea. .,Division of Bio-Medical Science & Technology, KIST School, Korea University of Science and Technology (UST), Seoul, 02792, Republic of Korea.
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Seeing Neurodegeneration in a New Light Using Genetically Encoded Fluorescent Biosensors and iPSCs. Int J Mol Sci 2023; 24:ijms24021766. [PMID: 36675282 PMCID: PMC9861453 DOI: 10.3390/ijms24021766] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 01/11/2023] [Accepted: 01/12/2023] [Indexed: 01/18/2023] Open
Abstract
Neurodegenerative diseases present a progressive loss of neuronal structure and function, leading to cell death and irrecoverable brain atrophy. Most have disease-modifying therapies, in part because the mechanisms of neurodegeneration are yet to be defined, preventing the development of targeted therapies. To overcome this, there is a need for tools that enable a quantitative assessment of how cellular mechanisms and diverse environmental conditions contribute to disease. One such tool is genetically encodable fluorescent biosensors (GEFBs), engineered constructs encoding proteins with novel functions capable of sensing spatiotemporal changes in specific pathways, enzyme functions, or metabolite levels. GEFB technology therefore presents a plethora of unique sensing capabilities that, when coupled with induced pluripotent stem cells (iPSCs), present a powerful tool for exploring disease mechanisms and identifying novel therapeutics. In this review, we discuss different GEFBs relevant to neurodegenerative disease and how they can be used with iPSCs to illuminate unresolved questions about causes and risks for neurodegenerative disease.
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10
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Tong BCK, Huang AS, Wu AJ, Iyaswamy A, Ho OKY, Kong AHY, Sreenivasmurthy SG, Zhu Z, Su C, Liu J, Song J, Li M, Cheung KH. Tetrandrine ameliorates cognitive deficits and mitigates tau aggregation in cell and animal models of tauopathies. J Biomed Sci 2022; 29:85. [PMID: 36273169 PMCID: PMC9587578 DOI: 10.1186/s12929-022-00871-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Accepted: 10/19/2022] [Indexed: 12/05/2022] Open
Abstract
Background Tauopathies are neurodegenerative diseases that are associated with the pathological accumulation of tau-containing tangles in the brain. Tauopathy can impair cognitive and motor functions and has been observed in Alzheimer’s disease (AD) and frontotemporal dementia (FTD). The aetiology of tauopathy remains mysterious; however, recent studies suggest that the autophagic-endolysosomal function plays an essential role in the degradation and transmission of pathological tau. We previously demonstrated that tetrandrine could ameliorate memory functions and clear amyloid plaques in transgenic AD mice by restoring autophagic-endolysosomal function. However, the efficacy of tetrandrine and the associated therapeutic mechanism in tauopathies have not been evaluated and elucidated. Methods Novel object recognition, fear conditioning and electrophysiology were used to evaluate the effects of tetrandrine on memory functions in transgenic tau mice. Western blotting and immunofluorescence staining were employed to determine the effect of tetrandrine on autophagy and tau clearance in vivo. Calcium (Ca2+) imaging and flow cytometry were used to delineate the role of pathological tau and tetrandrine in lysosomal Ca2+ and pH homeostasis. Biochemical BiFC fluorescence, Western blotting and immunofluorescence staining were used to evaluate degradation of hyperphosphorylated tau in vitro, whereas coculture of brain slices with isolated microglia was used to evaluate tau clearance ex vivo. Results We observed that tetrandrine treatment mitigated tau tangle development and corrected memory impairment in Thy1-hTau.P301S transgenic mice. Mechanistically, we showed that mutant tau expression disrupts lysosome pH by increasing two-pore channel 2 (TPC2)-mediated Ca2+ release, thereby contributing to lysosome alkalinization. Tetrandrine inhibits TPC2, thereby restoring the lysosomal pH, promotes tau degradation via autophagy, and ameliorates tau aggregation. Furthermore, in an ex vivo assay, we demonstrated that tetrandrine treatment promotes pathological tau clearance by microglia. Conclusions Together, these findings suggest that pathological tau disturbs endolysosomal homeostasis to impair tau clearance. This impairment results in a vicious cycle that accelerates disease pathogenesis. The success of tetrandrine in reducing tau aggregation suggests first, that tetrandrine could be an effective drug for tauopathies and second, that rescuing lysosomal Ca2+ homeostasis, thereby restoring ALP function, could be an effective general strategy for the development of novel therapies for tauopathies. Supplementary Information The online version contains supplementary material available at 10.1186/s12929-022-00871-6.
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Affiliation(s)
- Benjamin Chun-Kit Tong
- School of Chinese Medicine and Mr. and Mrs. Ko Chi Ming Centre for Parkinson's Disease Research, Hong Kong Baptist University, 7 Baptist University Road, Kowloon Tong, Kowloon, Hong Kong, SAR, China.
| | - Alexis Shiying Huang
- School of Chinese Medicine and Mr. and Mrs. Ko Chi Ming Centre for Parkinson's Disease Research, Hong Kong Baptist University, 7 Baptist University Road, Kowloon Tong, Kowloon, Hong Kong, SAR, China
| | - Aston Jiaxi Wu
- School of Chinese Medicine and Mr. and Mrs. Ko Chi Ming Centre for Parkinson's Disease Research, Hong Kong Baptist University, 7 Baptist University Road, Kowloon Tong, Kowloon, Hong Kong, SAR, China
| | - Ashok Iyaswamy
- School of Chinese Medicine and Mr. and Mrs. Ko Chi Ming Centre for Parkinson's Disease Research, Hong Kong Baptist University, 7 Baptist University Road, Kowloon Tong, Kowloon, Hong Kong, SAR, China
| | - Olivia Ka-Yi Ho
- School of Chinese Medicine and Mr. and Mrs. Ko Chi Ming Centre for Parkinson's Disease Research, Hong Kong Baptist University, 7 Baptist University Road, Kowloon Tong, Kowloon, Hong Kong, SAR, China
| | - Anna Hau-Yee Kong
- School of Chinese Medicine and Mr. and Mrs. Ko Chi Ming Centre for Parkinson's Disease Research, Hong Kong Baptist University, 7 Baptist University Road, Kowloon Tong, Kowloon, Hong Kong, SAR, China
| | - Sravan Gopalkrishnashetty Sreenivasmurthy
- School of Chinese Medicine and Mr. and Mrs. Ko Chi Ming Centre for Parkinson's Disease Research, Hong Kong Baptist University, 7 Baptist University Road, Kowloon Tong, Kowloon, Hong Kong, SAR, China
| | - Zhou Zhu
- School of Chinese Medicine and Mr. and Mrs. Ko Chi Ming Centre for Parkinson's Disease Research, Hong Kong Baptist University, 7 Baptist University Road, Kowloon Tong, Kowloon, Hong Kong, SAR, China
| | - Chengfu Su
- School of Chinese Medicine and Mr. and Mrs. Ko Chi Ming Centre for Parkinson's Disease Research, Hong Kong Baptist University, 7 Baptist University Road, Kowloon Tong, Kowloon, Hong Kong, SAR, China
| | - Jia Liu
- School of Chinese Medicine and Mr. and Mrs. Ko Chi Ming Centre for Parkinson's Disease Research, Hong Kong Baptist University, 7 Baptist University Road, Kowloon Tong, Kowloon, Hong Kong, SAR, China
| | - Juxian Song
- Medical College of Acupuncture-Moxibustion and Rehabilitation, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Min Li
- School of Chinese Medicine and Mr. and Mrs. Ko Chi Ming Centre for Parkinson's Disease Research, Hong Kong Baptist University, 7 Baptist University Road, Kowloon Tong, Kowloon, Hong Kong, SAR, China.
| | - King-Ho Cheung
- School of Chinese Medicine and Mr. and Mrs. Ko Chi Ming Centre for Parkinson's Disease Research, Hong Kong Baptist University, 7 Baptist University Road, Kowloon Tong, Kowloon, Hong Kong, SAR, China.
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11
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Towards a Mechanistic Model of Tau-Mediated Pathology in Tauopathies: What Can We Learn from Cell-Based In Vitro Assays? Int J Mol Sci 2022; 23:ijms231911527. [PMID: 36232835 PMCID: PMC9570106 DOI: 10.3390/ijms231911527] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2022] [Revised: 09/16/2022] [Accepted: 09/24/2022] [Indexed: 11/16/2022] Open
Abstract
Tauopathies are a group of neurodegenerative diseases characterized by the hyperphosphorylation and deposition of tau proteins in the brain. In Alzheimer’s disease, and other related tauopathies, the pattern of tau deposition follows a stereotypical progression between anatomically connected brain regions. Increasing evidence suggests that tau behaves in a “prion-like” manner, and that seeding and spreading of pathological tau drive progressive neurodegeneration. Although several advances have been made in recent years, the exact cellular and molecular mechanisms involved remain largely unknown. Since there are no effective therapies for any tauopathy, there is a growing need for reliable experimental models that would provide us with better knowledge and understanding of their etiology and identify novel molecular targets. In this review, we will summarize the development of cellular models for modeling tau pathology. We will discuss their different applications and contributions to our current understanding of the “prion-like” nature of pathological tau.
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12
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Samluk L, Ostapczuk P, Dziembowska M. Long-term mitochondrial stress induces early steps of Tau aggregation by increasing reactive oxygen species levels and affecting cellular proteostasis. Mol Biol Cell 2022; 33:ar67. [PMID: 35446108 PMCID: PMC9635289 DOI: 10.1091/mbc.e21-11-0553] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Accumulating evidence indicates that mitochondrial dysfunction is involved in the pathogenesis of neurodegenerative diseases. Both of these conditions are often associated with an increase in protein aggregation. However, still unknown are the specific defects of mitochondrial biology that play a critical role in the development of Alzheimer’s disease, in which Tau protein aggregates are observed in the brains of some patients. Here, we report that long-term mitochondrial stress triggered Tau dimerization, which is the first step of protein aggregation. Mitochondrial dysfunction was induced in HEK293T cells that received prolonged treatment with rotenone and in HEK293T cells with the knockout of NDUFA11 protein. To monitor changes in Tau protein aggregation, we took advantage of the bimolecular fluorescence complementation assay using HEK293T cells that were transfected with plasmids that encoded Tau. Inhibition of the ISR with ISRIB induced Tau dimerization, whereas ISR activation with salubrinal, guanabenz, and sephin1 partially reversed this process. Cells that were treated with ROS scavengers, N-acetyl-l-cysteine or MitoQ, significantly reduced the amount of ROS and Tau dimerization, indicating the involvement of oxidative stress in Tau aggregation. Our results indicate that long-term mitochondrial stress may induce early steps of Tau protein aggregation by affecting oxidative balance and cellular proteostasis.
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Affiliation(s)
- Lukasz Samluk
- Centre of New Technologies, University of Warsaw, S. Banacha 2c, 02-097 Warsaw, Poland
| | - Piotr Ostapczuk
- Centre of New Technologies, University of Warsaw, S. Banacha 2c, 02-097 Warsaw, Poland
| | - Magdalena Dziembowska
- Centre of New Technologies, University of Warsaw, S. Banacha 2c, 02-097 Warsaw, Poland
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13
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Torres-Garcia L, P Domingues JM, Brandi E, Haikal C, Mudannayake JM, Brás IC, Gerhardt E, Li W, Svanbergsson A, Outeiro TF, Gouras GK, Li JY. Monitoring the interactions between alpha-synuclein and Tau in vitro and in vivo using bimolecular fluorescence complementation. Sci Rep 2022; 12:2987. [PMID: 35194057 PMCID: PMC8863885 DOI: 10.1038/s41598-022-06846-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Accepted: 01/31/2022] [Indexed: 12/12/2022] Open
Abstract
Parkinson's disease (PD) and Alzheimer's disease (AD) are characterized by pathological accumulation and aggregation of different amyloidogenic proteins, α-synuclein (aSyn) in PD, and amyloid-β (Aβ) and Tau in AD. Strikingly, few PD and AD patients' brains exhibit pure pathology with most cases presenting mixed types of protein deposits in the brain. Bimolecular fluorescence complementation (BiFC) is a technique based on the complementation of two halves of a fluorescent protein, which allows direct visualization of protein-protein interactions. In the present study, we assessed the ability of aSyn and Tau to interact with each other. For in vitro evaluation, HEK293 and human neuroblastoma cells were used, while in vivo studies were performed by AAV6 injection in the substantia nigra pars compacta (SNpc) of mice and rats. We observed that the co-expression of aSyn and Tau led to the emergence of fluorescence, reflecting the interaction of the proteins in cell lines, as well as in mouse and rat SNpc. Thus, our data indicates that aSyn and Tau are able to interact with each other in a biologically relevant context, and that the BiFC assay is an effective tool for studying aSyn-Tau interactions in vitro and in different rodent models in vivo.
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Affiliation(s)
- Laura Torres-Garcia
- Experimental Dementia Research Unit, Department of Experimental Medical Science, Lund University, Lund, Sweden
- Neural Plasticity and Repair Unit, Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Joana M P Domingues
- Neural Plasticity and Repair Unit, Department of Experimental Medical Science, Lund University, Lund, Sweden
- Department of Clinical Neurosciences, University of Cambridge, The Clifford Albbutt Building, Cambridge, UK
| | - Edoardo Brandi
- Neural Plasticity and Repair Unit, Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Caroline Haikal
- Neural Plasticity and Repair Unit, Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Janitha M Mudannayake
- Developmental and Regenerative Neurobiology, Department of Experimental Medical Science, and Lund Stem Cell Center, Lund University, Lund, Sweden
| | - Inês C Brás
- Department of Experimental Neurodegeneration, Center for Biostructural Imaging of Neurodegeneration, Center for Nanoscale Microscopy and Molecular Physiology of the Brain, University Medical Center Göttingen, Göttingen, Germany
| | - Ellen Gerhardt
- Department of Experimental Neurodegeneration, Center for Biostructural Imaging of Neurodegeneration, Center for Nanoscale Microscopy and Molecular Physiology of the Brain, University Medical Center Göttingen, Göttingen, Germany
| | - Wen Li
- Neural Plasticity and Repair Unit, Department of Experimental Medical Science, Lund University, Lund, Sweden
- Institute of Health Sciences, China Medical University, Shenyang, China
| | - Alexander Svanbergsson
- Neural Plasticity and Repair Unit, Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Tiago F Outeiro
- Department of Experimental Neurodegeneration, Center for Biostructural Imaging of Neurodegeneration, Center for Nanoscale Microscopy and Molecular Physiology of the Brain, University Medical Center Göttingen, Göttingen, Germany
- Max Planck Institute for Experimental Medicine, Göttingen, Germany
- Faculty of Medical Sciences, Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne, UK
- Scientific Employee With an Honorary Contract at German Center for Neurodegenerative Diseases (DZNE), Göttingen, Germany
| | - Gunnar K Gouras
- Experimental Dementia Research Unit, Department of Experimental Medical Science, Lund University, Lund, Sweden.
| | - Jia-Yi Li
- Neural Plasticity and Repair Unit, Department of Experimental Medical Science, Lund University, Lund, Sweden.
- Institute of Health Sciences, China Medical University, Shenyang, China.
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14
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Yang C, Su C, Iyaswamy A, Krishnamoorthi SK, Zhu Z, Yang S, Tong BC, Liu J, Sreenivasmurthy SG, Guan X, Kan Y, Wu AJ, Huang AS, Tan J, Cheung K, Song J, Li M. Celastrol enhances transcription factor EB (TFEB)-mediated autophagy and mitigates Tau pathology: Implications for Alzheimer’s disease therapy. Acta Pharm Sin B 2022; 12:1707-1722. [PMID: 35847498 PMCID: PMC9279716 DOI: 10.1016/j.apsb.2022.01.017] [Citation(s) in RCA: 52] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Revised: 12/11/2021] [Accepted: 12/16/2021] [Indexed: 02/06/2023] Open
Abstract
Alzheimer's disease (AD), characterized by the accumulation of protein aggregates including phosphorylated Tau aggregates, is the most common neurodegenerative disorder with limited therapeutic agents. Autophagy plays a critical role in the degradation of phosphorylated Tau aggregates, and transcription factor EB (TFEB) is a master regulator of autophagy and lysosomal biogenesis. Thus, small-molecule autophagy enhancers targeting TFEB hold promise for AD therapy. Here, we found that celastrol, an active ingredient isolated from the root extracts of Tripterygium wilfordii (Lei Gong Teng in Chinese) enhanced TFEB-mediated autophagy and lysosomal biogenesis in vitro and in mouse brains. Importantly, celastrol reduced phosphorylated Tau aggregates and attenuated memory dysfunction and cognitive deficits in P301S Tau and 3xTg mice, two commonly used AD animal models. Mechanistical studies suggest that TFEB-mediated autophagy-lysosomal pathway is responsible for phosphorylated Tau degradation in response to celastrol. Overall, our findings indicate that Celastrol is a novel TFEB activator that promotes the degradation of phosphorylated Tau aggregates and improves memory in AD animal models. Therefore, Celastrol shows potential as a novel agent for the treatment and/or prevention of AD and other tauopathies.
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15
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Cytotoxic tau released from lung microvascular endothelial cells upon infection with Pseudomonas aeruginosa promotes neuronal tauopathy. J Biol Chem 2021; 298:101482. [PMID: 34896150 PMCID: PMC8718960 DOI: 10.1016/j.jbc.2021.101482] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 12/02/2021] [Accepted: 12/03/2021] [Indexed: 11/23/2022] Open
Abstract
Patients who recover from nosocomial pneumonia oftentimes exhibit long-lasting cognitive impairment comparable with what is observed in Alzheimer’s disease patients. We previously hypothesized that the lung endothelium contributes to infection-related neurocognitive dysfunction, because bacteria-exposed endothelial cells release a form(s) of cytotoxic tau that is sufficient to impair long-term potentiation in the hippocampus. However, the full-length lung and endothelial tau isoform(s) have yet to be resolved and it remains unclear whether the infection-induced endothelial cytotoxic tau triggers neuronal tau aggregation. Here, we demonstrate that lung endothelial cells express a big tau isoform and three additional tau isoforms that are similar to neuronal tau, each containing four microtubule-binding repeat domains, and that tau is expressed in lung capillaries in vivo. To test whether infection elicits endothelial tau capable of causing transmissible tau aggregation, the cells were infected with Pseudomonas aeruginosa. The infection-induced tau released from endothelium into the medium-induced neuronal tau aggregation in reporter cells, including reporter cells that express either the four microtubule-binding repeat domains or the full-length tau. Infection-induced release of pathological tau variant(s) from endothelium, and the ability of the endothelial-derived tau to cause neuronal tau aggregation, was abolished in tau knockout cells. After bacterial lung infection, brain homogenates from WT mice, but not from tau knockout mice, initiated tau aggregation. Thus, we conclude that bacterial pneumonia initiates the release of lung endothelial-derived cytotoxic tau, which is capable of propagating a neuronal tauopathy.
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16
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Lo CH. Recent advances in cellular biosensor technology to investigate tau oligomerization. Bioeng Transl Med 2021; 6:e10231. [PMID: 34589603 PMCID: PMC8459642 DOI: 10.1002/btm2.10231] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 05/04/2021] [Accepted: 05/05/2021] [Indexed: 12/12/2022] Open
Abstract
Tau is a microtubule binding protein which plays an important role in physiological functions but it is also involved in the pathogenesis of Alzheimer's disease and related tauopathies. While insoluble and β-sheet containing tau neurofibrillary tangles have been the histopathological hallmark of these diseases, recent studies suggest that soluble tau oligomers, which are formed prior to fibrils, are the primary toxic species. Substantial efforts have been made to generate tau oligomers using purified recombinant protein strategies to study oligomer conformations as well as their toxicity. However, no specific toxic tau species has been identified to date, potentially due to the lack of cellular environment. Hence, there is a need for cell-based models for direct monitoring of tau oligomerization and aggregation. This review will summarize the recent advances in the cellular biosensor technology, with a focus on fluorescence resonance energy transfer, bimolecular fluorescence complementation, and split luciferase complementation approaches, to monitor formation of tau oligomers and aggregates in living cells. We will discuss the applications of the cellular biosensors in examining the heterogeneous tau conformational ensembles and factors affecting tau self-assembly, as well as detecting cell-to-cell propagation of tau pathology. We will also compare the advantages and limitations of each type of tau biosensors, and highlight their translational applications in biomarker development and therapeutic discovery.
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Affiliation(s)
- Chih Hung Lo
- Department of Neurology, Brigham and Women's HospitalHarvard Medical SchoolBostonMassachusettsUSA
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17
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Subramanian M, Hyeon SJ, Das T, Suh YS, Kim YK, Lee JS, Song EJ, Ryu H, Yu K. UBE4B, a microRNA-9 target gene, promotes autophagy-mediated Tau degradation. Nat Commun 2021; 12:3291. [PMID: 34078905 PMCID: PMC8172564 DOI: 10.1038/s41467-021-23597-9] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Accepted: 04/29/2021] [Indexed: 02/07/2023] Open
Abstract
The formation of hyperphosphorylated intracellular Tau tangles in the brain is a hallmark of Alzheimer's disease (AD). Tau hyperphosphorylation destabilizes microtubules, promoting neurodegeneration in AD patients. To identify suppressors of tau-mediated AD, we perform a screen using a microRNA (miR) library in Drosophila and identify the miR-9 family as suppressors of human tau overexpression phenotypes. CG11070, a miR-9a target gene, and its mammalian orthologue UBE4B, an E3/E4 ubiquitin ligase, alleviate eye neurodegeneration, synaptic bouton defects, and crawling phenotypes in Drosophila human tau overexpression models. Total and phosphorylated Tau levels also decrease upon CG11070 or UBE4B overexpression. In mammalian neuroblastoma cells, overexpression of UBE4B and STUB1, which encodes the E3 ligase CHIP, increases the ubiquitination and degradation of Tau. In the Tau-BiFC mouse model, UBE4B and STUB1 overexpression also increase oligomeric Tau degradation. Inhibitor assays of the autophagy and proteasome systems reveal that the autophagy-lysosome system is the major pathway for Tau degradation in this context. These results demonstrate that UBE4B, a miR-9 target gene, promotes autophagy-mediated Tau degradation together with STUB1, and is thus an innovative therapeutic approach for AD.
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Affiliation(s)
- Manivannan Subramanian
- grid.249967.70000 0004 0636 3099Metabolism and Neurophysiology Research Group, KRIBB, Daejeon, Korea ,grid.511114.1Convergence Research Center of Dementia, KIST, Seoul, Korea
| | - Seung Jae Hyeon
- grid.35541.360000000121053345Center for Neuroscience, Brain Science Institute, KIST, Seoul, Korea
| | - Tanuza Das
- grid.35541.360000000121053345Biomedical Research Institute, KIST, Seoul, Korea
| | - Yoon Seok Suh
- grid.249967.70000 0004 0636 3099Metabolism and Neurophysiology Research Group, KRIBB, Daejeon, Korea
| | - Yun Kyung Kim
- grid.511114.1Convergence Research Center of Dementia, KIST, Seoul, Korea
| | - Jeong-Soo Lee
- grid.249967.70000 0004 0636 3099Metabolism and Neurophysiology Research Group, KRIBB, Daejeon, Korea ,grid.511114.1Convergence Research Center of Dementia, KIST, Seoul, Korea
| | - Eun Joo Song
- grid.255649.90000 0001 2171 7754Graduate School of Pharmaceutical Sciences and College of Pharmacy, Ewha Womans University, Seoul, Korea
| | - Hoon Ryu
- grid.35541.360000000121053345Center for Neuroscience, Brain Science Institute, KIST, Seoul, Korea
| | - Kweon Yu
- grid.249967.70000 0004 0636 3099Metabolism and Neurophysiology Research Group, KRIBB, Daejeon, Korea ,grid.511114.1Convergence Research Center of Dementia, KIST, Seoul, Korea ,grid.412786.e0000 0004 1791 8264Department of Functional Genomics, UST, Daejeon, Korea
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18
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Chung S, Yang J, Kim HJ, Hwang EM, Lee W, Suh K, Choi H, Mook-Jung I. Plexin-A4 mediates amyloid-β-induced tau pathology in Alzheimer's disease animal model. Prog Neurobiol 2021; 203:102075. [PMID: 34004220 DOI: 10.1016/j.pneurobio.2021.102075] [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: 07/17/2020] [Revised: 03/09/2021] [Accepted: 05/11/2021] [Indexed: 11/17/2022]
Abstract
Amyloid-β (Aβ) and tau are major pathological hallmarks of Alzheimer's disease (AD). Several studies have revealed that Aβ accelerates pathological tau transition and spreading during the disease progression, and that reducing tau can mitigate pathological features of AD. However, molecular links between Aβ and tau pathologies remain elusive. Here, we suggest a novel role for the plexin-A4 as an Aβ receptor that induces aggregated tau pathology. Plexin-A4, previously known as proteins involved in regulating axon guidance and synaptic plasticity, can bound to Aβ with co-receptor, neuropilin-2. Genetic downregulation of plexin-A4 in neurons was sufficient to prevent Aβ-induced activation of CDK5 and reduce tau hyperphosphorylation and aggregation, even in the presence of Aβ. In an AD mouse model that manifests both Aβ and tau pathologies, genetic downregulation of plexin-A4 in the hippocampus reduced tau pathology and ameliorated spatial memory impairment. Collectively, these results indicate that the plexin-A4 is capable of mediating Aβ-induced tau pathology in AD pathogenesis.
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Affiliation(s)
- Sunwoo Chung
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul 03080, South Korea; SNU Dementia Research Center, Seoul National University College of Medicine, Seoul 03080, South Korea.
| | - Jinhee Yang
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul 03080, South Korea; Biorchestra Co., Ltd., Techno 4-ro 17, Daejeon 34013, South Korea.
| | - Haeng Jun Kim
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul 03080, South Korea; SNU Dementia Research Center, Seoul National University College of Medicine, Seoul 03080, South Korea.
| | - Eun Mi Hwang
- Center for Functional Connectomics, Korea Institute of Science and Technology (KIST), Seoul 02792, South Korea.
| | - Wonik Lee
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul 03080, South Korea; SNU Dementia Research Center, Seoul National University College of Medicine, Seoul 03080, South Korea.
| | - Kyujin Suh
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul 03080, South Korea; SNU Dementia Research Center, Seoul National University College of Medicine, Seoul 03080, South Korea.
| | - Hayoung Choi
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul 03080, South Korea; SNU Dementia Research Center, Seoul National University College of Medicine, Seoul 03080, South Korea.
| | - Inhee Mook-Jung
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul 03080, South Korea; SNU Dementia Research Center, Seoul National University College of Medicine, Seoul 03080, South Korea.
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19
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Don EK, Maschirow A, Radford RAW, Scherer NM, Vidal-Itriago A, Hogan A, Maurel C, Formella I, Stoddart JJ, Hall TE, Lee A, Shi B, Cole NJ, Laird AS, Badrock AP, Chung RS, Morsch M. In vivo Validation of Bimolecular Fluorescence Complementation (BiFC) to Investigate Aggregate Formation in Amyotrophic Lateral Sclerosis (ALS). Mol Neurobiol 2021; 58:2061-2074. [PMID: 33415684 PMCID: PMC8018926 DOI: 10.1007/s12035-020-02238-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Accepted: 11/25/2020] [Indexed: 10/28/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) is a form of motor neuron disease (MND) that is characterized by the progressive loss of motor neurons within the spinal cord, brainstem, and motor cortex. Although ALS clinically manifests as a heterogeneous disease, with varying disease onset and survival, a unifying feature is the presence of ubiquitinated cytoplasmic protein inclusion aggregates containing TDP-43. However, the precise mechanisms linking protein inclusions and aggregation to neuronal loss are currently poorly understood. Bimolecular fluorescence complementation (BiFC) takes advantage of the association of fluorophore fragments (non-fluorescent on their own) that are attached to an aggregation-prone protein of interest. Interaction of the proteins of interest allows for the fluorescent reporter protein to fold into its native state and emit a fluorescent signal. Here, we combined the power of BiFC with the advantages of the zebrafish system to validate, optimize, and visualize the formation of ALS-linked aggregates in real time in a vertebrate model. We further provide in vivo validation of the selectivity of this technique and demonstrate reduced spontaneous self-assembly of the non-fluorescent fragments in vivo by introducing a fluorophore mutation. Additionally, we report preliminary findings on the dynamic aggregation of the ALS-linked hallmark proteins Fus and TDP-43 in their corresponding nuclear and cytoplasmic compartments using BiFC. Overall, our data demonstrates the suitability of this BiFC approach to study and characterize ALS-linked aggregate formation in vivo. Importantly, the same principle can be applied in the context of other neurodegenerative diseases and has therefore critical implications to advance our understanding of pathologies that underlie aberrant protein aggregation.
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Affiliation(s)
- Emily K Don
- Centre for Motor Neuron Disease Research, Faculty of Medicine, Health and Human Sciences, Department of Biomedical Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Alina Maschirow
- Centre for Motor Neuron Disease Research, Faculty of Medicine, Health and Human Sciences, Department of Biomedical Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Rowan A W Radford
- Centre for Motor Neuron Disease Research, Faculty of Medicine, Health and Human Sciences, Department of Biomedical Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Natalie M Scherer
- Centre for Motor Neuron Disease Research, Faculty of Medicine, Health and Human Sciences, Department of Biomedical Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Andrés Vidal-Itriago
- Centre for Motor Neuron Disease Research, Faculty of Medicine, Health and Human Sciences, Department of Biomedical Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Alison Hogan
- Centre for Motor Neuron Disease Research, Faculty of Medicine, Health and Human Sciences, Department of Biomedical Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Cindy Maurel
- Centre for Motor Neuron Disease Research, Faculty of Medicine, Health and Human Sciences, Department of Biomedical Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Isabel Formella
- Centre for Motor Neuron Disease Research, Faculty of Medicine, Health and Human Sciences, Department of Biomedical Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Jack J Stoddart
- Centre for Motor Neuron Disease Research, Faculty of Medicine, Health and Human Sciences, Department of Biomedical Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Thomas E Hall
- Institute for Molecular Bioscience, The University of Queensland, QLD, St Lucia, 4072, Australia
| | - Albert Lee
- Centre for Motor Neuron Disease Research, Faculty of Medicine, Health and Human Sciences, Department of Biomedical Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Bingyang Shi
- Centre for Motor Neuron Disease Research, Faculty of Medicine, Health and Human Sciences, Department of Biomedical Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Nicholas J Cole
- Centre for Motor Neuron Disease Research, Faculty of Medicine, Health and Human Sciences, Department of Biomedical Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Angela S Laird
- Centre for Motor Neuron Disease Research, Faculty of Medicine, Health and Human Sciences, Department of Biomedical Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Andrew P Badrock
- Centre for Motor Neuron Disease Research, Faculty of Medicine, Health and Human Sciences, Department of Biomedical Sciences, Macquarie University, Sydney, NSW, 2109, Australia.
| | - Roger S Chung
- Centre for Motor Neuron Disease Research, Faculty of Medicine, Health and Human Sciences, Department of Biomedical Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Marco Morsch
- Centre for Motor Neuron Disease Research, Faculty of Medicine, Health and Human Sciences, Department of Biomedical Sciences, Macquarie University, Sydney, NSW, 2109, Australia.
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20
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Shin YH, Cho H, Choi BY, Kim J, Ha J, Suh SW, Park SB. Phenotypic Discovery of Neuroprotective Agents by Regulation of Tau Proteostasis via Stress-Responsive Activation of PERK Signaling. Angew Chem Int Ed Engl 2021; 60:1831-1838. [PMID: 33210431 PMCID: PMC7898623 DOI: 10.1002/anie.202013915] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Indexed: 02/06/2023]
Abstract
Tau protein aggregates are a recognized neuropathological feature in Alzheimer's disease as well as many other neurodegenerative disorders, known as tauopathies. The development of tau-targeting therapies is therefore extremely important but efficient strategies or protein targets are still unclear. Here, we performed a cell-based phenotypic screening under endoplasmic reticulum (ER) stress conditions and identified a small molecule, SB1617, capable of suppressing abnormal tau protein aggregation. By applying label-free target identification technology, we revealed that the transient enhancement of protein kinase-like endoplasmic reticulum kinase (PERK) signaling pathway through the inhibition of stress-responsive SB1617 targets, PDIA3 and DNAJC3, is an effective strategy for regulating proteostasis in tauopathies. The molecular mechanism and the promising efficacy of SB1617 were demonstrated in neuronal cells and a mouse model with traumatic brain injury, a tauopathy known to involve ER stress.
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Affiliation(s)
- Young-Hee Shin
- CRI Center for Chemical Proteomics, Department of Chemistry, Seoul National University, Seoul, 08826, Korea
| | - Hana Cho
- Department of Biophysics and Chemical Biology, Seoul National University, Seoul, 08826, Korea
| | - Bo Young Choi
- Department of Physiology, College of Medicine, Hallym University, Chuncheon, 24252, Korea
| | - Jonghoon Kim
- CRI Center for Chemical Proteomics, Department of Chemistry, Seoul National University, Seoul, 08826, Korea.,Present address: Department of Chemistry, Soongsil University, Seoul, 06978, Korea
| | - Jaeyoung Ha
- Department of Biophysics and Chemical Biology, Seoul National University, Seoul, 08826, Korea
| | - Sang Won Suh
- Department of Physiology, College of Medicine, Hallym University, Chuncheon, 24252, Korea
| | - Seung Bum Park
- CRI Center for Chemical Proteomics, Department of Chemistry, Seoul National University, Seoul, 08826, Korea.,Department of Biophysics and Chemical Biology, Seoul National University, Seoul, 08826, Korea
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21
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Kim H, Ju J, Lee HN, Chun H, Seong J. Genetically Encoded Biosensors Based on Fluorescent Proteins. SENSORS (BASEL, SWITZERLAND) 2021; 21:795. [PMID: 33504068 PMCID: PMC7865379 DOI: 10.3390/s21030795] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 01/21/2021] [Accepted: 01/22/2021] [Indexed: 02/06/2023]
Abstract
Genetically encoded biosensors based on fluorescent proteins (FPs) allow for the real-time monitoring of molecular dynamics in space and time, which are crucial for the proper functioning and regulation of complex cellular processes. Depending on the types of molecular events to be monitored, different sensing strategies need to be applied for the best design of FP-based biosensors. Here, we review genetically encoded biosensors based on FPs with various sensing strategies, for example, translocation, fluorescence resonance energy transfer (FRET), reconstitution of split FP, pH sensitivity, maturation speed, and so on. We introduce general principles of each sensing strategy and discuss critical factors to be considered if available, then provide representative examples of these FP-based biosensors. These will help in designing the best sensing strategy for the successful development of new genetically encoded biosensors based on FPs.
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Affiliation(s)
- Hyunbin Kim
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul 02792, Korea; (H.K.); (J.J.); (H.N.L.); (H.C.)
- Division of Bio-Medical Science & Technology, KIST School, Korea University of Science and Technology, Seoul 02792, Korea
| | - Jeongmin Ju
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul 02792, Korea; (H.K.); (J.J.); (H.N.L.); (H.C.)
- Division of Bio-Medical Science & Technology, KIST School, Korea University of Science and Technology, Seoul 02792, Korea
| | - Hae Nim Lee
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul 02792, Korea; (H.K.); (J.J.); (H.N.L.); (H.C.)
- Department of Converging Science and Technology, Kyung Hee University, Seoul 02453, Korea
| | - Hyeyeon Chun
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul 02792, Korea; (H.K.); (J.J.); (H.N.L.); (H.C.)
| | - Jihye Seong
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul 02792, Korea; (H.K.); (J.J.); (H.N.L.); (H.C.)
- Division of Bio-Medical Science & Technology, KIST School, Korea University of Science and Technology, Seoul 02792, Korea
- Department of Converging Science and Technology, Kyung Hee University, Seoul 02453, Korea
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22
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Uptake of Polyelectrolyte Functionalized Upconversion Nanoparticles by Tau-Aggregated Neuron Cells. Pharmaceutics 2021; 13:pharmaceutics13010102. [PMID: 33466898 PMCID: PMC7829809 DOI: 10.3390/pharmaceutics13010102] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 01/10/2021] [Accepted: 01/12/2021] [Indexed: 01/09/2023] Open
Abstract
Tauopathy is the aggregation phenomenon of tau proteins and associated with neurodegenerative diseases. It metastasizes via the transfer of tau aggregates to adjacent neuron cells; however, the mechanism has not yet been fully understood. Moreover, if the materials used for designing drug delivery system to treat such neurodegenerative diseases do not undergo biodegradation or exocytosis but remains in cells or tissues, they raise concerns about their possible negative impacts. In this study, the uptake and delivery mechanisms of nano-sized carriers in tau aggregated neuron cells were investigated employing polyelectrolyte-functionalized upconversion nanoparticles (UCNPs) of diameter ~100 nm. Investigation through bioimaging was carried out by irradiating the particles with near-infrared light. Here, forskolin and okadaic acid were employed to induce tau aggregation into healthy neuron cells. It was noticed that the tau-aggregated neuron cells, when treated with relatively large sized UCNPs, showed uptake efficiency similar to that of normal neuron cells however their intracellular transport and exocytosis were impacted, and most of the carriers remained accumulated around lysosome. This demonstrates that metastasis mechanisms of tauopathy can get influenced by the size of carriers and are to be considered during their pharmacokinetic studies which is often not addressed in many drug delivery studies.
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23
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Shin Y, Cho H, Choi BY, Kim J, Ha J, Suh SW, Park SB. Phenotypic Discovery of Neuroprotective Agents by Regulation of Tau Proteostasis via Stress‐Responsive Activation of PERK Signaling. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202013915] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Young‐Hee Shin
- CRI Center for Chemical Proteomics Department of Chemistry Seoul National University Seoul 08826 Korea
| | - Hana Cho
- Department of Biophysics and Chemical Biology Seoul National University Seoul 08826 Korea
| | - Bo Young Choi
- Department of Physiology College of Medicine Hallym University Chuncheon 24252 Korea
| | - Jonghoon Kim
- CRI Center for Chemical Proteomics Department of Chemistry Seoul National University Seoul 08826 Korea
- Present address: Department of Chemistry Soongsil University Seoul 06978 Korea
| | - Jaeyoung Ha
- Department of Biophysics and Chemical Biology Seoul National University Seoul 08826 Korea
| | - Sang Won Suh
- Department of Physiology College of Medicine Hallym University Chuncheon 24252 Korea
| | - Seung Bum Park
- CRI Center for Chemical Proteomics Department of Chemistry Seoul National University Seoul 08826 Korea
- Department of Biophysics and Chemical Biology Seoul National University Seoul 08826 Korea
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24
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Lo CH, Sachs JN. The role of wild-type tau in Alzheimer's disease and related tauopathies. JOURNAL OF LIFE SCIENCES (WESTLAKE VILLAGE, CALIF.) 2020; 2:1-17. [PMID: 33665646 PMCID: PMC7929479 DOI: 10.36069/jols/20201201] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Tau oligomers have recently emerged as the principal toxic species in Alzheimer's disease (AD) and tauopathies. Tau oligomers are spontaneously self-assembled soluble tau proteins that are formed prior to fibrils, and they have been shown to play a central role in neuronal cell death and in the induction of neurodegeneration in animal models. As the therapeutic paradigm shifts to targeting toxic tau oligomers, this suggests the focus to study tau oligomerization in species that are less susceptible to fibrillization. While truncated and mutation containing tau as well as the isolated repeat domains are particularly prone to fibrillization, the wild-type (WT) tau proteins have been shown to be resistant to fibril formation in the absence of aggregation inducers. In this review, we will summarize and discuss the toxicity of WT tau both in vitro and in vivo, as well as its involvement in tau oligomerization and cell-to-cell propagation of pathology. Understanding the role of WT tau will enable more effective biomarker development and therapeutic discovery for treatment of AD and tauopathies.
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Affiliation(s)
- Chih Hung Lo
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN 55455
- Department of Neurology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115
| | - Jonathan N. Sachs
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN 55455
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25
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Oakley SS, Maina MB, Marshall KE, Al-Hilaly YK, Harrington CR, Wischik CM, Serpell LC. Tau Filament Self-Assembly and Structure: Tau as a Therapeutic Target. Front Neurol 2020; 11:590754. [PMID: 33281730 PMCID: PMC7688747 DOI: 10.3389/fneur.2020.590754] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2020] [Accepted: 09/04/2020] [Indexed: 12/12/2022] Open
Abstract
Tau plays an important pathological role in a group of neurodegenerative diseases called tauopathies, including Alzheimer's disease, Pick's disease, chronic traumatic encephalopathy and corticobasal degeneration. In each disease, tau self-assembles abnormally to form filaments that deposit in the brain. Tau is a natively unfolded protein that can adopt distinct structures in different pathological disorders. Cryo-electron microscopy has recently provided a series of structures for the core of the filaments purified from brain tissue from patients with different tauopathies and revealed that they share a common core region, while differing in their specific conformation. This structurally resolvable part of the core is contained within a proteolytically stable core region from the repeat domain initially isolated from AD tau filaments. Tau has recently become an important target for therapy. Recent work has suggested that the prevention of tau self-assembly may be effective in slowing the progression of Alzheimer's disease and other tauopathies. Here we review the work that explores the importance of tau filament structures and tau self-assembly mechanisms, as well as examining model systems that permit the exploration of the mode of action of potential inhibitors.
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Affiliation(s)
- Sebastian S Oakley
- Sussex Neuroscience, School of Life Sciences, University of Sussex, Brighton, United Kingdom
| | - Mahmoud B Maina
- Sussex Neuroscience, School of Life Sciences, University of Sussex, Brighton, United Kingdom.,College of Medical Sciences, Yobe State University, Damaturu, Nigeria
| | - Karen E Marshall
- Sussex Neuroscience, School of Life Sciences, University of Sussex, Brighton, United Kingdom
| | - Youssra K Al-Hilaly
- Sussex Neuroscience, School of Life Sciences, University of Sussex, Brighton, United Kingdom.,Chemistry Department, College of Science, Mustansiriyah University, Baghdad, Iraq
| | - Charlie R Harrington
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, United Kingdom.,TauRx Therapeutics Ltd., Aberdeen, United Kingdom
| | - Claude M Wischik
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, United Kingdom.,TauRx Therapeutics Ltd., Aberdeen, United Kingdom
| | - Louise C Serpell
- Sussex Neuroscience, School of Life Sciences, University of Sussex, Brighton, United Kingdom
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26
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Heo CE, Han JY, Lim S, Lee J, Im D, Lee MJ, Kim YK, Kim HI. ATP Kinetically Modulates Pathogenic Tau Fibrillations. ACS Chem Neurosci 2020; 11:3144-3152. [PMID: 32915536 DOI: 10.1021/acschemneuro.0c00479] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Advanced understanding of Alzheimer's disease (AD) and several tauopathies over the past decades indicates the pathological importance of tau aggregation in these diseases. Herein, we demonstrated that adenosine triphosphate (ATP), a highly charged anionic molecule found abundantly in the cytosol of cells, catalyzes fibrillation of tau as well as human islet amyloid polypeptide, a representative of basic intrinsically disordered proteins. Our results showed that ATP attracts multiple lysine residues of the four-repeat domain of tau (K18) via supramolecular complexation, thereby forming dimers that are converted to nuclei and accelerate fibril elongation. However, ATP was not directly incorporated into the K18 fibrils, suggesting that ATP plays the role of a catalyst, rather than a reactant, during K18 fibrillation. We also characterized the correlation between ATP dyshomeostasis and tau aggregation in the cellular environment. Our multiple biophysical approaches, including native mass spectrometry (MS), small-angle X-ray scattering (SAXS), and molecular dynamics (MD) simulation, provided insights into the molecular-level influence of ATP on the structural changes and fibrillation of tau.
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Affiliation(s)
- Chae Eun Heo
- Department of Chemistry, Korea University, Seoul 02841, Republic of Korea
- Center for Proteogenomics Research, Korea University, Seoul 02841, Republic of Korea
| | - Jong Yoon Han
- Department of Chemistry, Korea University, Seoul 02841, Republic of Korea
- Center for Proteogenomics Research, Korea University, Seoul 02841, Republic of Korea
| | - Sungsu Lim
- Brain Science Institute, Center for Neuromedicine, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea
| | - Jeeyoung Lee
- Department of Biomedical Sciences, Neuroscience Research Institute, Seoul National University College of Medicine, Seoul 03080, Republic of Korea
| | - Dongjoon Im
- Department of Chemistry, Korea University, Seoul 02841, Republic of Korea
- Center for Proteogenomics Research, Korea University, Seoul 02841, Republic of Korea
| | - Min Jae Lee
- Department of Biomedical Sciences, Neuroscience Research Institute, Seoul National University College of Medicine, Seoul 03080, Republic of Korea
| | - Yun Kyung Kim
- Brain Science Institute, Center for Neuromedicine, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea
- Department of Biological Chemistry, University of Science and Technology (UST), Daejeon 34113, Republic of Korea
| | - Hugh I. Kim
- Department of Chemistry, Korea University, Seoul 02841, Republic of Korea
- Center for Proteogenomics Research, Korea University, Seoul 02841, Republic of Korea
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27
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Shin S, Kim D, Song JY, Jeong H, Hyeon SJ, Kowall NW, Ryu H, Pae AN, Lim S, Kim YK. Visualization of soluble tau oligomers in TauP301L-BiFC transgenic mice demonstrates the progression of tauopathy. Prog Neurobiol 2020; 187:101782. [PMID: 32105751 DOI: 10.1016/j.pneurobio.2020.101782] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 02/16/2020] [Accepted: 02/21/2020] [Indexed: 11/30/2022]
Abstract
Accumulation of abnormal tau aggregates in the brain is a pathological hallmark of multiple neurodegenerative disorders including Alzheimer's disease. Increasing evidence suggests that soluble tau aggregates play a key role in tau pathology as neurotoxic species causing neuronal cell death and act as prion-like seeds mediating tau propagation. Despite the pathological relevance, there is a paucity of methods to monitor tau oligomerization in the brain. As a tool to monitor tau self-assembly in the brain, we generated a novel tau transgenic mouse, named TauP301L-BiFC. By introducing bimolecular fluorescence complementation technique to human tau containing a P301L mutation, we were able to monitor and quantify tau self-assembly, represented by BiFC fluorescence in the brains of transgenic TauP301L-BiFC mice. TauP301L-BiFC mice showed soluble tau oligomerization from 3 months, showing significantly enriched BiFC fluorescence in the brain. Then, massive tau fragmentation occured at 6 months showing dramatically decreased TauP301L-BiFC fluorescence. The fragmented tau species served as a seed for insoluble tau aggregation. In a result, insoluble TauP301L-BiFC aggregates coaggregated with endogenous mouse tau accumulated in the brain, showing subsequently increased BiFC fluorescence from 9 months. Neuronal degeneration and cognitive deficits were observed from 12 months of age. TauP301L-BiFC mouse model demonstrated that methylene blue reduced the amount of soluble tau oligomers in the brain, resulting in the prevention of cognitive impairments. We assure that TauP301L-BiFC mice are a bona-fide animal tool to monitor pathological tau oligomerization in AD and other tauopathies.
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Affiliation(s)
- Seulgi Shin
- Convergence Research Center for Diagnosis, Treatment and Care System of Dementia, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea; Division of Bio-Medical Science & Technology, KIST School, University of Science and Technology (UST), Seoul, 02792, Republic of Korea
| | - Dohee Kim
- Convergence Research Center for Diagnosis, Treatment and Care System of Dementia, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
| | - Ji Yeon Song
- Convergence Research Center for Diagnosis, Treatment and Care System of Dementia, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
| | - Hyeanjeong Jeong
- Convergence Research Center for Diagnosis, Treatment and Care System of Dementia, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea; Department of Life Sciences, School of Life Sciences and Biotechnology, Korea University, Seoul, 02841, Republic of Korea
| | - Seung Jae Hyeon
- Center for Neuroscience, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
| | - Neil W Kowall
- Boston University Alzheimer's Disease Center and Department of Neurology, Boston University School of Medicine, Boston, MA 02118, USA
| | - Hoon Ryu
- Center for Neuroscience, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea; Boston University Alzheimer's Disease Center and Department of Neurology, Boston University School of Medicine, Boston, MA 02118, USA
| | - Ae Nim Pae
- Convergence Research Center for Diagnosis, Treatment and Care System of Dementia, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea; Division of Bio-Medical Science & Technology, KIST School, University of Science and Technology (UST), Seoul, 02792, Republic of Korea
| | - Sungsu Lim
- Convergence Research Center for Diagnosis, Treatment and Care System of Dementia, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea.
| | - Yun Kyung Kim
- Convergence Research Center for Diagnosis, Treatment and Care System of Dementia, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea; Division of Bio-Medical Science & Technology, KIST School, University of Science and Technology (UST), Seoul, 02792, Republic of Korea.
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28
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A dual inhibitor of the proteasome catalytic subunits LMP2 and Y attenuates disease progression in mouse models of Alzheimer's disease. Sci Rep 2019; 9:18393. [PMID: 31804556 PMCID: PMC6895163 DOI: 10.1038/s41598-019-54846-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Accepted: 11/15/2019] [Indexed: 12/18/2022] Open
Abstract
The immunoproteasome (iP) is a variant of the constitutive proteasome (cP) that is abundantly expressed in immune cells which can also be induced in somatic cells by cytokines such as TNF-α or IFN-γ. Accumulating evidence support that the iP is closely linked to multiple facets of inflammatory response, eventually leading to the development of several iP inhibitors as potential therapeutic agents for autoimmune diseases. Recent studies also found that the iP is upregulated in reactive glial cells surrounding amyloid β (Aβ) deposits in brains of Alzheimer’s disease (AD) patients, but the role it plays in the pathogenesis of AD remains unclear. In this study, we investigated the effects of several proteasome inhibitors on cognitive function in AD mouse models and found that YU102, a dual inhibitor of the iP catalytic subunit LMP2 and the cP catalytic subunit Y, ameliorates cognitive impairments in AD mouse models without affecting Aβ deposition. The data obtained from our investigation revealed that YU102 suppresses the secretion of inflammatory cytokines from microglial cells. Overall, this study indicates that there may exist a potential link between LMP2/Y and microglia-mediated neuroinflammation and that inhibition of these subunits may offer a new therapeutic strategy for AD.
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29
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Lo CH, Lim CKW, Ding Z, Wickramasinghe SP, Braun AR, Ashe KH, Rhoades E, Thomas DD, Sachs JN. Targeting the ensemble of heterogeneous tau oligomers in cells: A novel small molecule screening platform for tauopathies. Alzheimers Dement 2019; 15:1489-1502. [PMID: 31653529 DOI: 10.1016/j.jalz.2019.06.4954] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Revised: 05/30/2019] [Accepted: 06/19/2019] [Indexed: 12/22/2022]
Abstract
OBJECTIVE Understanding the heterogeneous pathology in Alzheimer's disease and related tauopathies is one of the most urgent and fundamental challenges facing the discovery of novel disease-modifying therapies. Through monitoring ensembles of toxic and nontoxic tau oligomers spontaneously formed in cells, our biosensor technology can identify tool compounds that modulate tau oligomer structure and toxicity, providing much needed insight into the nature and properties of toxic tau oligomers. BACKGROUND Tauopathies are a group of neurodegenerative disorders characterized by pathologic aggregation of the microtubule binding protein tau. Recent studies suggest that tau oligomers are the primary toxic species in tauopathies. NEW/UPDATED HYPOTHESIS We hypothesize that tau biosensors capable of monitoring tau oligomer conformation are able to identify tool compounds that modulate the structure and conformation of these tau assemblies, providing key insight into the unique structural fingerprints of toxic tau oligomers. These fingerprints will provide gravely needed biomarker profiles to improve staging of early tauopathy pathology and generate lead compounds for potential new therapeutics. Our time-resolved fluorescence resonance energy transfer biosensors provide us an exquisitely sensitive technique to monitor minute structural changes in monomer and oligomer conformation. In this proof-of-concept study, we identified a novel tool compound, MK-886, which directly binds tau, perturbs the conformation of toxic tau oligomers, and rescues tau-induced cytotoxicity. Furthermore, we show that MK-886 alters the conformation of tau monomer at the proline-rich and microtubule binding regions, stabilizing an on-pathway oligomer. MAJOR CHALLENGES FOR THE HYPOTHESIS Our approach monitors changes in the ensemble of assemblies that are spontaneously formed in cells but does not specifically isolate or enrich unique toxic tau species. However, time-resolved fluorescence resonance energy transfer does not provide high-resolution, atomic scale information, requiring additional experimental techniques to resolve the structural features stabilized by different tool compounds. LINKAGE TO OTHER MAJOR THEORIES Our biosensor technology is broadly applicable to other areas of tauopathy therapeutic development. These biosensors can be readily modified for different isoforms of tau, specific post-translational modifications, and familial Alzheimer's disease-associated mutations. We are eager to explore tau interactions with chaperone proteins, monitor cross-reactivity with other intrinsically disordered proteins, and target seeded oligomer pathology.
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Affiliation(s)
- Chih Hung Lo
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN, USA
| | - Colin Kin-Wye Lim
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN, USA
| | - Zhipeng Ding
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN, USA
| | - Sanjula P Wickramasinghe
- Biochemistry and Molecular Biophysics Graduate Group, University of Pennsylvania, Philadelphia, PA, USA
| | - Anthony R Braun
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN, USA
| | - Karen H Ashe
- Department of Neurology, University of Minnesota, Minneapolis, MN, USA; Department of Neuroscience, University of Minnesota, Minneapolis, MN, USA; N. Bud Grossman Center for Memory Research and Care, University of Minnesota, Minneapolis, MN, USA; Geriatric Research, Education, and Clinical Centers, Veterans Affairs Medical Center, Minneapolis, MN, USA
| | - Elizabeth Rhoades
- Biochemistry and Molecular Biophysics Graduate Group, University of Pennsylvania, Philadelphia, PA, USA; Department of Chemistry, University of Pennsylvania, Philadelphia, PA, USA
| | - David D Thomas
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN, USA; Photonic Pharma LLC, Minneapolis, MN, USA
| | - Jonathan N Sachs
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN, USA.
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30
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Pan-HDAC Inhibitors Promote Tau Aggregation by Increasing the Level of Acetylated Tau. Int J Mol Sci 2019; 20:ijms20174283. [PMID: 31480543 PMCID: PMC6747090 DOI: 10.3390/ijms20174283] [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: 08/01/2019] [Revised: 08/28/2019] [Accepted: 08/29/2019] [Indexed: 12/21/2022] Open
Abstract
Epigenetic remodeling via histone acetylation has become a popular therapeutic strategy to treat Alzheimer's disease (AD). In particular, histone deacetylase (HDAC) inhibitors including M344 and SAHA have been elucidated to be new drug candidates for AD, improving cognitive abilities impaired in AD mouse models. Although emerged as a promising target for AD, most of the HDAC inhibitors are poorly selective and could cause unwanted side effects. Here we show that tau is one of the cytosolic substrates of HDAC and the treatment of HDAC inhibitors such as Scriptaid, M344, BML281, and SAHA could increase the level of acetylated tau, resulting in the activation of tau pathology.
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31
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Siano G, Caiazza MC, Ollà I, Varisco M, Madaro G, Quercioli V, Calvello M, Cattaneo A, Di Primio C. Identification of an ERK Inhibitor as a Therapeutic Drug Against Tau Aggregation in a New Cell-Based Assay. Front Cell Neurosci 2019; 13:386. [PMID: 31496937 PMCID: PMC6712076 DOI: 10.3389/fncel.2019.00386] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Accepted: 08/06/2019] [Indexed: 01/01/2023] Open
Abstract
Formation of Tau aggregates is a common pathological feature of tauopathies and their accumulation directly correlates with cytotoxicity and neuronal degeneration. Great efforts have been made to understand Tau aggregation and to find therapeutics halting or reversing the process, however, progress has been slowed due to the lack of a suitable method for monitoring Tau aggregation. We developed a cell-based assay allowing to detect and quantify Tau aggregation in living cells. The system is based on the FRET biosensor CST able to monitor the molecular dynamic of Tau aggregation in different cellular conditions. We probed candidate compounds that could block Tau hyperphosphorylation. In particular, to foster the drug discovery process, we tested kinase inhibitors approved for the treatment of other diseases. We identified the ERK inhibitor PD-901 as a promising therapeutic molecule since it reduces and prevents Tau aggregation. This evidence establishes the CST cell-based aggregation assay as a reliable tool for drug discovery and suggests that PD-901 might be a promising compound to be tested for further preclinical studies on AD.
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Affiliation(s)
- Giacomo Siano
- Laboratorio di Biologia (BIO@SNS), Scuola Normale Superiore, Pisa, Italy
| | | | - Ivana Ollà
- Laboratorio di Biologia (BIO@SNS), Scuola Normale Superiore, Pisa, Italy
| | - Martina Varisco
- Laboratorio di Biologia (BIO@SNS), Scuola Normale Superiore, Pisa, Italy
| | - Giuseppe Madaro
- Laboratorio di Biologia (BIO@SNS), Scuola Normale Superiore, Pisa, Italy
| | | | | | - Antonino Cattaneo
- Laboratorio di Biologia (BIO@SNS), Scuola Normale Superiore, Pisa, Italy.,Neurotrophins and Neurodegenerative Diseases Laboratory, Rita Levi-Montalcini European Brain Research Institute, Rome, Italy
| | - Cristina Di Primio
- Laboratorio di Biologia (BIO@SNS), Scuola Normale Superiore, Pisa, Italy
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Park JS, Lee J, Jung ES, Kim MH, Kim IB, Son H, Kim S, Kim S, Park YM, Mook-Jung I, Yu SJ, Lee JH. Brain somatic mutations observed in Alzheimer's disease associated with aging and dysregulation of tau phosphorylation. Nat Commun 2019; 10:3090. [PMID: 31300647 PMCID: PMC6626023 DOI: 10.1038/s41467-019-11000-7] [Citation(s) in RCA: 84] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Accepted: 06/14/2019] [Indexed: 01/24/2023] Open
Abstract
The role of brain somatic mutations in Alzheimer’s disease (AD) is not well understood. Here, we perform deep whole-exome sequencing (average read depth 584×) in 111 postmortem hippocampal formation and matched blood samples from 52 patients with AD and 11 individuals not affected by AD. The number of somatic single nucleotide variations (SNVs) in AD brain specimens increases significantly with aging, and the rate of mutation accumulation in the brain is 4.8-fold slower than that in AD blood. The putatively pathogenic brain somatic mutations identified in 26.9% (14 of 52) of AD individuals are enriched in PI3K-AKT, MAPK, and AMPK pathway genes known to contribute to hyperphosphorylation of tau. We show that a pathogenic brain somatic mutation in PIN1 leads to a loss-of-function mutation. In vitro mimicking of haploinsufficiency of PIN1 aberrantly increases tau phosphorylation and aggregation. This study provides new insights into the genetic architecture underlying the pathogenesis of AD. The role of brain somatic mutations in neurodegenerative diseases such as Alzheimer’s disease (AD) is not well understood. Here the authors carry out high-depth exome sequencing ~500× on brain tissue from patients with AD and controls, and identify mutations in a number of genes that are known to contribute to phosphorylation and aggregation of tau, including PIN1.
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Affiliation(s)
- Jun Sung Park
- Biomedical Science and Engineering Interdisciplinary Program, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Junehawk Lee
- Center for Supercomputing Applications, Division of National Supercomputing, Korea Institute of Science and Technology Information, Daejeon, 34141, Republic of Korea
| | - Eun Sun Jung
- Department of Biochemistry and Biomedical Sciences, College of Medicine, Seoul National University, Seoul, 03080, Republic of Korea.,Neuroscience Research Institute, College of Medicine, Seoul National University, Seoul, 03080, Republic of Korea
| | - Myeong-Heui Kim
- Biomedical Science and Engineering Interdisciplinary Program, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Il Bin Kim
- Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Hyeonju Son
- Department of Biomedical Systems Informatics, Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, 03722, South Korea
| | - Sangwoo Kim
- Department of Biomedical Systems Informatics, Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, 03722, South Korea
| | - Sanghyeon Kim
- Laboratory of Brain Research, Stanley Medical Research Institute (SMRI), 9800 Medical Center Drive, Suite C-050, Rockville, MD, 20850, USA
| | - Young Mok Park
- Center for Cognition and Sociality, Institute for Basic Science (IBS), Daejeon, 34126, Republic of Korea
| | - Inhee Mook-Jung
- Department of Biochemistry and Biomedical Sciences, College of Medicine, Seoul National University, Seoul, 03080, Republic of Korea.,Neuroscience Research Institute, College of Medicine, Seoul National University, Seoul, 03080, Republic of Korea
| | - Seok Jong Yu
- Center for Supercomputing Applications, Division of National Supercomputing, Korea Institute of Science and Technology Information, Daejeon, 34141, Republic of Korea.
| | - Jeong Ho Lee
- Biomedical Science and Engineering Interdisciplinary Program, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea. .,Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea.
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33
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Boban M, Leko MB, Miškić T, Hof PR, Šimić G. Human neuroblastoma SH-SY5Y cells treated with okadaic acid express phosphorylated high molecular weight tau-immunoreactive protein species. J Neurosci Methods 2019; 319:60-68. [PMID: 30278184 PMCID: PMC6440880 DOI: 10.1016/j.jneumeth.2018.09.030] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Revised: 09/06/2018] [Accepted: 09/27/2018] [Indexed: 01/01/2023]
Abstract
BACKGROUND Early stages of Alzheimer's disease (AD) are characterized by high phosphorylation of microtubule-associated protein tau, which may result from the downregulation of protein phosphatases. NEW METHOD In order to model phosphatase downregulation and analyze its effect on tau aggregation in vitro, we treated neuroblastoma SH-SY5Y cells with okadaic acid (OA), a protein phosphatase inhibitor, and examined high molecular weight phospho-tau species. RESULTS AND COMPARISON WITH EXISTING METHODS OA treatment led to the appearance of heat-stable protein species with apparent molecular weight around 100 kDa, which were immunoreactive to anti-tau antibodies against phosphorylated Ser202 and Ser396. As these high molecular weight tau-immunoreactive proteins (HMW-TIPs) corresponded to the predicted size of two tau monomers, we considered the possibility that they represent phosphorylation-induced tau oligomers. We attempted to dissociate HMW-TIPs by urea and guanidine, as well as by alkaline phosphatase treatment, but HMW-TIPs were stable under all conditions tested. These characteristics resemble properties of certain sodium dodecyl sulfate (SDS)-resistant tau oligomers from AD brains. The absence of HMW-TIPs detection by anti-total tau antibodies Tau46, CP27 and Tau13 may be a consequence of epitope masking and protein truncation. Alternatively, HMW-TIPs may represent previously unreported phosphoproteins cross-reacting with tau. CONCLUSIONS Taken together, our data provide a novel characterization of an OA-based cell culture model in which OA induces the appearance of HMW-TIPs. These findings have implications for further studies of tau under the conditions of protein phosphatase downregulation, aiming to explain mechanisms involved in early events leading to AD.
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Affiliation(s)
- Mirta Boban
- Department of Neuroscience, Croatian Institute for Brain Research, University of Zagreb Medical School, Zagreb, Croatia
| | - Mirjana Babić Leko
- Department of Neuroscience, Croatian Institute for Brain Research, University of Zagreb Medical School, Zagreb, Croatia
| | - Terezija Miškić
- Department of Neuroscience, Croatian Institute for Brain Research, University of Zagreb Medical School, Zagreb, Croatia
| | - Patrick R. Hof
- Fishberg Department of Neuroscience, Ronald M. Loeb Center for Alzheimer’s Disease, and Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, United States of America
| | - Goran Šimić
- Department of Neuroscience, Croatian Institute for Brain Research, University of Zagreb Medical School, Zagreb, Croatia,corresponding author
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Development of tau-directed small molecule modulators for Alzheimer's disease: a recent patent review (2014-2018). Pharm Pat Anal 2019; 8:15-39. [PMID: 30870110 DOI: 10.4155/ppa-2019-0003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disease that is characterized by memory loss and cognitive impairment. As this disease is becoming a serious global health issue, development of disease modifying therapeutics is urgently required. AD is characterized by deposits of two protein, amyloid β and tau. Although amyloid β-based therapeutics have been extensively investigated so far, tau has also received great attention as one of promising molecular targets for AD. In this review, a variety of tau-directed strategies to rescue tau-mediated neurotoxicity will be reviewed especially focusing on small molecules. Subsequently, recent patents published from 2014 to 2018 that integrate efforts to develop tau-directed small molecules for the treatment of AD will be reviewed.
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Farag AK, Hassan AHE, Jeong H, Kwon Y, Choi JG, Oh MS, Park KD, Kim YK, Roh EJ. First-in-class DAPK1/CSF1R dual inhibitors: Discovery of 3,5-dimethoxy-N-(4-(4-methoxyphenoxy)-2-((6-morpholinopyridin-3-yl)amino)pyrimidin-5-yl)benzamide as a potential anti-tauopathies agent. Eur J Med Chem 2018; 162:161-175. [PMID: 30445265 DOI: 10.1016/j.ejmech.2018.10.057] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Revised: 10/15/2018] [Accepted: 10/23/2018] [Indexed: 01/06/2023]
Abstract
Kinase irregularity has been correlated with several complex neurodegenerative tauopathies. Development of selective inhibitors of these kinases might afford promising anti-tauopathy therapies. While DAPK1 inhibitors halt the formation of tau aggregates and counteract neuronal death, CSF1R inhibitors could alleviate the tauopathies-associated neuroinflammation. Herein, we report the design, synthesis, biological evaluation, mechanistic study, and molecular docking study of novel CSF1R/DAPK1 dual inhibitors as multifunctional molecules inhibiting the formation of tau aggregates and neuroinflammation. Compound 3l, the most potent DAPK1 inhibitor in the in vitro kinase assay (IC50 = 1.25 μM) was the most effective tau aggregates formation inhibitor in the cellular assay (IC50 = 5.0 μM). Also, compound 3l elicited potent inhibition of CSF1R in the in vitro kinase assay (IC50 = 0.15 μM) and promising inhibition of nitric oxide production in LPS-induced BV-2 cells (55% inhibition at 10 μM concentration). Kinase profiling and hERG binding assay anticipated the absence of off-target toxicities while the PAMPA-BBB assay predicted potentially high BBB permeability. The mechanistic study and selectivity profile suggest compound 3l as a non-ATP-competitive DAPK1 inhibitor and an ATP-competitive CSF1R inhibitor while the in silico calculations illustrated binding of compound 3l to the substrate-binding site of DAPK1. Hence, compound 3l might act as a protein-protein interaction inhibitor by hindering DAPK1 kinase reaction through preventing the binding of DAPK1 substrates.
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Affiliation(s)
- Ahmed Karam Farag
- Chemical Kinomics Research Center, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea; Division of Bio-Medical Science &Technology, KIST School, University of Science and Technology, Seoul, 02792, Republic of Korea
| | - Ahmed H E Hassan
- Department of Medicinal Chemistry, Faculty of Pharmacy, Mansoura University, Mansoura, 35516, Egypt; Medicinal Chemistry Laboratory, Department of Pharmacy, College of Pharmacy, Kyung Hee University, Seoul, 02447, Republic of Korea
| | - Hyeanjeong Jeong
- Brain Science Institute, Convergence Research Center for Diagnosis, Treatment and Care System of Dementia, Korea Institute of Science and Technology (KIST), Seoul, 02791, Republic of Korea; Department of Life Science, Korea University, Seoul, 02841, Republic of Korea
| | - Youngji Kwon
- Department of Life and Nanopharmaceutical Sciences, Graduate School, Kyung Hee University, Seoul, Republic of Korea
| | - Jin Gyu Choi
- BK21 PLUS Integrated Education and Research Center for Nature-inspired Drug Development Targeting Healthy Aging, Kyung Hee University, Seoul, Republic of Korea
| | - Myung Sook Oh
- Department of Life and Nanopharmaceutical Sciences, Graduate School, Kyung Hee University, Seoul, Republic of Korea
| | - Ki Duk Park
- Division of Bio-Medical Science &Technology, KIST School, University of Science and Technology, Seoul, 02792, Republic of Korea; Convergence Research Center for Diagnosis, Treatment and Care System of Dementia, Korea Institute of Science and Technology (KIST), Republic of Korea
| | - Yun Kyung Kim
- Division of Bio-Medical Science &Technology, KIST School, University of Science and Technology, Seoul, 02792, Republic of Korea; Brain Science Institute, Convergence Research Center for Diagnosis, Treatment and Care System of Dementia, Korea Institute of Science and Technology (KIST), Seoul, 02791, Republic of Korea
| | - Eun Joo Roh
- Chemical Kinomics Research Center, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea; Division of Bio-Medical Science &Technology, KIST School, University of Science and Technology, Seoul, 02792, Republic of Korea.
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36
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Shin S, Lim S, Jeong H, Kwan LT, Kim YK. Visualization of Tau⁻Tubulin Interaction in a Living Cell Using Bifluorescence Complementation Technique. Int J Mol Sci 2018; 19:ijms19102978. [PMID: 30274285 PMCID: PMC6213793 DOI: 10.3390/ijms19102978] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2018] [Revised: 09/22/2018] [Accepted: 09/27/2018] [Indexed: 11/17/2022] Open
Abstract
Tau is a neuron-specific microtubule-binding protein that stabilizes microtubules. It is generally thought that highly phosphorylated tau dissociates from microtubules and becomes insoluble aggregates, leading to neuronal degeneration. Due to the implication of tau aggregation in neurodegenerative disorders, including Alzheimer’s disease, great efforts have been made to identify the tau aggregation process. However, tau interaction with tubulin during the aggregation process remains largely unknown. To scrutinize the tau-tubulin interaction, we generated a cell model that enables visualization of the tau-tubulin interaction in a living cell using the Bifluorescence Complementation (BiFC) Technique. Upon diverse chemical stimulation that induced tau pathology, tau-tubulin BiFC cells showed significantly increased levels of BiFC fluorescence, indicating that tau aggregates together with tubulin. Our results suggest that tubulin should be considered as a key component in the tau aggregation process.
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Affiliation(s)
- Seulgi Shin
- Korea Institute of Science and Technology (KIST), Brain Science Institute, Convergence Research Center for Diagnosis, Treatment and Care System of Dementia, Seoul 02792, Korea.
| | - Sungsu Lim
- Korea Institute of Science and Technology (KIST), Brain Science Institute, Convergence Research Center for Diagnosis, Treatment and Care System of Dementia, Seoul 02792, Korea.
| | - Hyeanjeong Jeong
- Korea Institute of Science and Technology (KIST), Brain Science Institute, Convergence Research Center for Diagnosis, Treatment and Care System of Dementia, Seoul 02792, Korea.
- Department of Life Science, Korea University, Seoul 02841, Korea.
| | - Li Ting Kwan
- Korea Institute of Science and Technology (KIST), Brain Science Institute, Convergence Research Center for Diagnosis, Treatment and Care System of Dementia, Seoul 02792, Korea.
- Department of Neuroscience, Wellesley College, Wellesley, MA 02481, USA.
| | - Yun Kyung Kim
- Korea Institute of Science and Technology (KIST), Brain Science Institute, Convergence Research Center for Diagnosis, Treatment and Care System of Dementia, Seoul 02792, Korea.
- Division of Bio-Medical Science & Technology, University of Science and Technology (UST), Daejeon 34113, Korea.
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37
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Li D, Wang L, Maziuk BF, Yao X, Wolozin B, Cho YK. Directed evolution of a picomolar-affinity, high-specificity antibody targeting phosphorylated tau. J Biol Chem 2018; 293:12081-12094. [PMID: 29899114 PMCID: PMC6078456 DOI: 10.1074/jbc.ra118.003557] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Revised: 06/12/2018] [Indexed: 01/03/2023] Open
Abstract
Antibodies are essential biochemical reagents for detecting protein post-translational modifications (PTMs) in complex samples. However, recent efforts in developing PTM-targeting antibodies have reported frequent nonspecific binding and limited affinity of such antibodies. To address these challenges, we investigated whether directed evolution could be applied to improve the affinity of a high-specificity antibody targeting phosphothreonine 231 (pThr-231) of the human microtubule-associated protein tau. On the basis of existing structural information, we hypothesized that improving antibody affinity may come at the cost of loss in specificity. To test this hypothesis, we developed a novel approach using yeast surface display to quantify the specificity of PTM-targeting antibodies. When we affinity-matured the single-chain variable antibody fragment through directed evolution, we found that its affinity can be improved >20-fold over that of the WT antibody, reaching a picomolar range. We also discovered that most of the high-affinity variants exhibit cross-reactivity toward the nonphosphorylated target site but not to the phosphorylation site with a scrambled sequence. However, systematic quantification of the specificity revealed that such a tradeoff between the affinity and specificity did not apply to all variants and led to the identification of a picomolar-affinity variant that has a matching high specificity of the original phosphotau antibody. In cell- and tissue-imaging experiments, the high-affinity variant gave significantly improved signal intensity while having no detectable nonspecific binding. These results demonstrate that directed evolution is a viable approach for obtaining high-affinity PTM-specific antibodies and highlight the importance of assessing the specificity in the antibody engineering process.
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Affiliation(s)
- Dan Li
- Department of Biomedical Engineering, University of Connecticut, Storrs, Connecticut 06269
| | - Lei Wang
- Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269
| | - Brandon F Maziuk
- Department of Pharmacology and Experimental Therapeutics, Boston University School of Medicine, Boston, Massachusetts 02118
| | - Xudong Yao
- Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269; Department of Institute for Systems Genomics, University of Connecticut, Storrs, Connecticut 06269
| | - Benjamin Wolozin
- Department of Pharmacology and Experimental Therapeutics, Boston University School of Medicine, Boston, Massachusetts 02118
| | - Yong Ku Cho
- Department of Biomedical Engineering, University of Connecticut, Storrs, Connecticut 06269; Department of Institute for Systems Genomics, University of Connecticut, Storrs, Connecticut 06269; Department of Chemical and Biomolecular Engineering, University of Connecticut, Storrs, Connecticut 06269.
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38
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Glioblastoma-secreted soluble CD44 activates tau pathology in the brain. Exp Mol Med 2018; 50:1-11. [PMID: 29622771 PMCID: PMC5938049 DOI: 10.1038/s12276-017-0008-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Revised: 10/19/2017] [Accepted: 10/24/2017] [Indexed: 01/08/2023] Open
Abstract
During aggressive tumor growth and migration, glioblastoma cells secrete diverse molecules and adhesion proteins to the extracellular matrix. Yet, the biochemical effects of the glioblastoma secretome in the brain remain largely unknown. Here we show that soluble CD44 secreted from glioblastoma cells induces neuronal degeneration through the activation of tau pathology in the brain. Glioblastoma-xenograft tissues showed a number of degenerating neurons bearing highly phosphorylated tau. Through a series of secretome-analyses, we identified that soluble CD44 was the responsible protein inducing tau phosphorylation and aggregation (EC50 = 19.1 ng/mL). The treatment of sCD44 to primary hippocampal neurons-induced tau hyperphosphorylation, leading to neuronal degeneration. Also, the injection of sCD44 into the brains of tau transgenic mice induced tau hyper-phosphorylation in hippocampal neurons. Altogether, our data suggest a neurodegenerative role of sCD44 in promoting tau pathology and serving as a molecular link between glioblastoma and neurodegeneration. A protein secreted by aggressive brain tumors triggers the degeneration of neurons in surrounding brain tissues. The most aggressive brain tumors are formed by glioblastoma cells, which secrete molecules that infiltrate surrounding brain tissues, leading to loss of memory, communication and motor functions. Researchers led by Cheolju Lee and Yun Kyung Kim at the Korea Institute of Science and Technology in Seoul have shown that the CD44 protein, secreted by glioblastoma cells, is responsible for triggering this neurodegeneration. They discovered that sCD44 activates another process known as tau pathology, which is characteristic of multiple neuro-degnerative disorders such as Alzheimer’s disease. The tau protein usually stabilizes internal cellular structures, but when it is modified by abnormal activity such as the elevated levels of sCD44 found in this study, it forms insoluble masses, disrupting neuronal structure and function.
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39
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Park SM. Hopping from One Cell to Another: Huntington's Disease Propagates. Exp Neurobiol 2018; 26:319-320. [PMID: 29302198 PMCID: PMC5746496 DOI: 10.5607/en.2017.26.6.319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Affiliation(s)
- Sang Myun Park
- Department of Pharmacology, Ajou University School of Medicine, Suwon 16499, Korea.,Chronic Inflammatory Disease Research Center, Ajou University School of Medicine, Suwon 16499, Korea.,BK21 plus program, Department of Biological Sciences, Ajou University School of Medicine, Suwon 16499, Korea
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40
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Di Primio C, Quercioli V, Siano G, Rovere M, Kovacech B, Novak M, Cattaneo A. The Distance between N and C Termini of Tau and of FTDP-17 Mutants Is Modulated by Microtubule Interactions in Living Cells. Front Mol Neurosci 2017; 10:210. [PMID: 28713242 PMCID: PMC5492851 DOI: 10.3389/fnmol.2017.00210] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Accepted: 06/14/2017] [Indexed: 11/22/2022] Open
Abstract
The microtubule (MT)-associated protein Tau is a natively unfolded protein, involved in a number of neurodegenerative disorders, collectively called tauopathies, aggregating in neurofibrillary tangles (NFT). It is an open question how the conversion from a MT bound molecule to an aggregation-prone Tau species occurs and, also, if and how tauopathy-related mutations affect its behavior in the cell. To address these points, we exploited a genetically encoded FRET sensor based on the full length Tau protein, to monitor in real time Tau conformational changes in different conditions in live cells. By studying the FRET signal we found that soluble Tau molecules, detached from MTs, display an unfolded structure. On the contrary, we observed an increased FRET signal generated by Tau monomers bound to MT, indicating that the association with MTs induced a folding of Tau protein, decreasing the distance between its N and C termini. We exploited the FRET sensor to investigate the impact of FTDP-17 mutations and of phosphorylation-site mutations on Tau folding and mobility in live cells. We demonstrated that the FTDP-17 Tau mutations weaken the interaction of Tau with cellular MTs, shifting the equilibrium towards the soluble pool while, conversely, phosphorylation site mutations shift the equilibrium of Tau towards the MT-bound state and a more closed conformation.
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Affiliation(s)
| | | | - Giacomo Siano
- Bio@SNS Laboratory, Scuola Normale SuperiorePisa, Italy
| | - Matteo Rovere
- Bio@SNS Laboratory, Scuola Normale SuperiorePisa, Italy
| | - Branislav Kovacech
- Institute of Neuroimmunology, Slovak Academy of Sciences, Axon Neuroscience SEBratislava, Slovakia
| | - Michal Novak
- Institute of Neuroimmunology, Slovak Academy of Sciences, Axon Neuroscience SEBratislava, Slovakia
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41
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Transcriptome analyses of chronic traumatic encephalopathy show alterations in protein phosphatase expression associated with tauopathy. Exp Mol Med 2017; 49:e333. [PMID: 28524178 PMCID: PMC5454448 DOI: 10.1038/emm.2017.56] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2016] [Revised: 01/05/2017] [Accepted: 01/17/2017] [Indexed: 12/14/2022] Open
Abstract
Chronic traumatic encephalopathy (CTE) is a progressive neurodegenerative disorder that is associated with repetitive head injury and has distinctive neuropathological features that differentiate this disease from other neurodegenerative diseases. Intraneuronal tau aggregates, although they occur in different patterns, are diagnostic neuropathological features of CTE, but the precise mechanism of tauopathy is not known in CTE. We performed whole RNA sequencing analysis of post-mortem brain tissue from patients with CTE and compared the results to normal controls to determine the transcriptome signature changes associated with CTE. The results showed that the genes related to the MAP kinase and calcium-signaling pathways were significantly downregulated in CTE. The altered expression of protein phosphatases (PPs) in these networks further suggested that the tauopathy observed in CTE involves common pathological mechanisms similar to Alzheimer's disease (AD). Using cell lines and animal models, we also showed that reduced PPP3CA/PP2B phosphatase activity is directly associated with increases in phosphorylated (p)-tau proteins. These findings provide important insights into PP-dependent neurodegeneration and may lead to novel therapeutic approaches to reduce the tauopathy associated with CTE.
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42
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Kyne C, Jordon K, Filoti DI, Laue TM, Crowley PB. Protein charge determination and implications for interactions in cell extracts. Protein Sci 2017; 26:258-267. [PMID: 27813264 PMCID: PMC5275725 DOI: 10.1002/pro.3077] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Revised: 10/24/2016] [Accepted: 10/27/2016] [Indexed: 01/30/2023]
Abstract
Decades of dilute-solution studies have revealed the influence of charged residues on protein stability, solubility and stickiness. Similar characterizations are now required in physiological solutions to understand the effect of charge on protein behavior under native conditions. Toward this end, we used free boundary and native gel electrophoresis to explore the charge of cytochrome c in buffer and in Escherichia coli extracts. We find that the charge of cytochrome c was ∼2-fold lower than predicted from primary structure analysis. Cytochrome c charge was tuned by sulfate binding and was rendered anionic in E. coli extracts due to interactions with macroanions. Mutants in which three or four cationic residues were replaced with glutamate were charge-neutral and "inert" in extracts. A comparison of the interaction propensities of cytochrome c and the mutants emphasizes the role of negative charge in stabilizing physiological environments. Charge-charge repulsion and preferential hydration appear to prevent aggregation. The implications for molecular organization in vivo are discussed.
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Affiliation(s)
- Ciara Kyne
- School of ChemistryNational University of IrelandGalway, University RoadGalwayIreland
| | - Kiara Jordon
- Spin Analytical468 Portland StreetBerwickMaine03901
| | - Dana I. Filoti
- Centre to Advance Macromolecular Interaction Sciences University of New HampshireDurhamNew Hampshire03824
| | - Thomas M. Laue
- Spin Analytical468 Portland StreetBerwickMaine03901
- Centre to Advance Macromolecular Interaction Sciences University of New HampshireDurhamNew Hampshire03824
| | - Peter B. Crowley
- School of ChemistryNational University of IrelandGalway, University RoadGalwayIreland
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43
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Holmes BB, Diamond MI. Cellular Models for the Study of Prions. Cold Spring Harb Perspect Med 2017; 7:cshperspect.a024026. [PMID: 27815306 DOI: 10.1101/cshperspect.a024026] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
It is now established that numerous amyloid proteins associated with neurodegenerative diseases, including tau and α-synuclein, have essential characteristics of prions, including the ability to create transmissible cellular pathology in vivo. We have developed cellular bioassays that report on the various features of prion activity using genetic engineering and quantitative fluorescence-based detection systems. We have exploited these biosensors to measure the binding and uptake of tau seeds into cells in culture and to quantify seeding activity in brain samples. These cell models have also been used to propagate tau prion strains indefinitely in culture. In this review, we illustrate the utility of cellular biosensors to gain mechanistic insight into prion transmission and to study neurodegenerative diseases in a reductionist fashion.
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Affiliation(s)
- Brandon B Holmes
- Medical Scientist Training Program, Washington University School of Medicine, St. Louis, Missouri 63110.,Center for Alzheimer's and Neurodegenerative Diseases, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Marc I Diamond
- Center for Alzheimer's and Neurodegenerative Diseases, University of Texas Southwestern Medical Center, Dallas, Texas 75390
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44
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Lim S, Haque MM, Su D, Kim D, Lee JS, Chang YT, Kim YK. Development of a BODIPY-based fluorescent probe for imaging pathological tau aggregates in live cells. Chem Commun (Camb) 2017; 53:1607-1610. [PMID: 28084493 DOI: 10.1039/c6cc08826k] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Neuronal accumulation of tau aggregates is a pathological hallmark in multiple neurodegenerative disorders, collectively called tauopathies. A tau aggregation sensor that can monitor abnormal tau aggregation in neurons would facilitate the study of tau aggregation processes and the discovery of tau aggregation blockers. Here, we describe a BODIPY-fluorescence sensor (BD-tau) that selectively responds to pathological tau aggregates in live cells.
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Affiliation(s)
- Sungsu Lim
- Korea Institute of Science and Technology (KIST), Convergence Research Center for Diagnosis, Treatment and Care System of Dementia, Seoul 136-791, South Korea.
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45
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Lim S, Kim D, Kim DJ, Kim YK. Image-Based Analysis of Intracellular Tau Aggregation by Using Tau-BiFC Cell Model. Methods Mol Biol 2017; 1523:341-347. [PMID: 27975262 DOI: 10.1007/978-1-4939-6598-4_22] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Abnormal tau aggregation is a pathological hallmark of neurodegenerative disease classified as tauopathy. Preventing tau aggregation becomes an important therapeutic strategy to cure tau-mediated neurodegeneration. Here, we describe a method to investigate intracellular tau aggregation by using a recently developed tau aggregation cell-based model named tau-BiFC. High-throughput and high-contents screening method for quantifying intracellular tau aggregation would expedite the discovery of drugs that inhibit tau aggregation.
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Affiliation(s)
- Sungsu Lim
- Convergence Research Center for Diagnosis, Treatment and Care System of Dementia, Brain Science Institute, Korea Institute of Science and Technology (KIST), Hwarangro 14-gil 5, Seongbuk-gu, Seoul, 136-791, South Korea
| | - Dohee Kim
- Convergence Research Center for Diagnosis, Treatment and Care System of Dementia, Brain Science Institute, Korea Institute of Science and Technology (KIST), Hwarangro 14-gil 5, Seongbuk-gu, Seoul, 136-791, South Korea
- Department of Biotechnology, Translational Research Center for Protein Function Control, College of Life Science and Biotechnology, Yonsei University, Seoul, 120-749, South Korea
| | - Dong Jin Kim
- Center for neuro-medicine, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 136-791, South Korea
| | - Yun Kyung Kim
- Convergence Research Center for Diagnosis, Treatment and Care System of Dementia, Brain Science Institute, Korea Institute of Science and Technology (KIST), Hwarangro 14-gil 5, Seongbuk-gu, Seoul, 136-791, South Korea.
- Biological Chemistry, University of Science and Technology (UST), Daejeon, 305-333, South Korea.
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46
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Jiang Y, Lee J, Lee JH, Lee JW, Kim JH, Choi WH, Yoo YD, Cha-Molstad H, Kim BY, Kwon YT, Noh SA, Kim KP, Lee MJ. The arginylation branch of the N-end rule pathway positively regulates cellular autophagic flux and clearance of proteotoxic proteins. Autophagy 2016; 12:2197-2212. [PMID: 27560450 DOI: 10.1080/15548627.2016.1222991] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The N-terminal amino acid of a protein is an essential determinant of ubiquitination and subsequent proteasomal degradation in the N-end rule pathway. Using para-chloroamphetamine (PCA), a specific inhibitor of the arginylation branch of the pathway (Arg/N-end rule pathway), we identified that blocking the Arg/N-end rule pathway significantly impaired the fusion of autophagosomes with lysosomes. Under ER stress, ATE1-encoded Arg-tRNA-protein transferases carry out the N-terminal arginylation of the ER heat shock protein HSPA5 that initially targets cargo proteins, along with SQSTM1, to the autophagosome. At the late stage of autophagy, however, proteasomal degradation of arginylated HSPA5 might function as a critical checkpoint for the proper progression of autophagic flux in the cells. Consistently, the inhibition of the Arg/N-end rule pathway with PCA significantly elevated levels of MAPT and huntingtin aggregates, accompanied by increased numbers of LC3 and SQSTM1 puncta. Cells treated with the Arg/N-end rule inhibitor became more sensitized to proteotoxic stress-induced cytotoxicity. SILAC-based quantitative proteomics also revealed that PCA significantly alters various biological pathways, including cellular responses to stress, nutrient, and DNA damage, which are also closely involved in modulation of autophagic responses. Thus, our results indicate that the Arg/N-end rule pathway may function to actively protect cells from detrimental effects of cellular stresses, including proteotoxic protein accumulation, by positively regulating autophagic flux.
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Affiliation(s)
- Yanxialei Jiang
- a Department of Biochemistry and Molecular Biology , Seoul National University College of Medicine , Seoul , Korea
| | - Jeeyoung Lee
- a Department of Biochemistry and Molecular Biology , Seoul National University College of Medicine , Seoul , Korea.,b Department of Biomedical Sciences , Seoul National University Graduate School , Seoul , Korea
| | - Jung Hoon Lee
- a Department of Biochemistry and Molecular Biology , Seoul National University College of Medicine , Seoul , Korea.,b Department of Biomedical Sciences , Seoul National University Graduate School , Seoul , Korea
| | - Joon Won Lee
- d Department of Applied Chemistry , College of Applied Sciences, Kyung Hee University , Yongin , Korea
| | - Ji Hyeon Kim
- a Department of Biochemistry and Molecular Biology , Seoul National University College of Medicine , Seoul , Korea.,b Department of Biomedical Sciences , Seoul National University Graduate School , Seoul , Korea
| | - Won Hoon Choi
- a Department of Biochemistry and Molecular Biology , Seoul National University College of Medicine , Seoul , Korea.,b Department of Biomedical Sciences , Seoul National University Graduate School , Seoul , Korea
| | - Young Dong Yoo
- b Department of Biomedical Sciences , Seoul National University Graduate School , Seoul , Korea
| | - Hyunjoo Cha-Molstad
- c World Class Institute, Korea Research Institute of Bioscience and Biotechnology , Ochang, Cheongwon , Korea
| | - Bo Yeon Kim
- c World Class Institute, Korea Research Institute of Bioscience and Biotechnology , Ochang, Cheongwon , Korea
| | - Yong Tae Kwon
- b Department of Biomedical Sciences , Seoul National University Graduate School , Seoul , Korea
| | - Sue Ah Noh
- d Department of Applied Chemistry , College of Applied Sciences, Kyung Hee University , Yongin , Korea
| | - Kwang Pyo Kim
- d Department of Applied Chemistry , College of Applied Sciences, Kyung Hee University , Yongin , Korea
| | - Min Jae Lee
- a Department of Biochemistry and Molecular Biology , Seoul National University College of Medicine , Seoul , Korea.,b Department of Biomedical Sciences , Seoul National University Graduate School , Seoul , Korea
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47
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Kim JH, Kim E, Choi WH, Lee J, Lee JH, Lee H, Kim DE, Suh YH, Lee MJ. Inhibitory RNA Aptamers of Tau Oligomerization and Their Neuroprotective Roles against Proteotoxic Stress. Mol Pharm 2016; 13:2039-48. [PMID: 27120117 DOI: 10.1021/acs.molpharmaceut.6b00165] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Tau is a cytosolic protein that functions in the assembly and stabilization of axonal microtubule networks. Its oligomerization may be the rate-limiting step of insoluble aggregate formation, which is a neuropathological hallmark of Alzheimer's disease (AD) and a number of other tauopathies. Recent evidence indicates that soluble tau oligomers are the toxic species for tau-mediated pathology during AD progression. Herein, we describe novel RNA aptamers that target human tau and were identified through an in vitro selection process. These aptamers significantly inhibited the oligomerization propensity of tau both in vitro and in cultured cell models of tauopathy without affecting the half-life of tau. Tauopathy model cells treated with the aptamers were less sensitized to proteotoxic stress induced by tau overexpression. Moreover, the tau aptamers significantly alleviated synthetic tau oligomer-mediated neurotoxicity and dendritic spine loss in primary hippocampal neurons. Thus, our study demonstrates that delaying tau assembly with RNA aptamers is an effective strategy for protecting cells under various neurodegenerative stresses originating from pathogenic tau oligomerization.
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Affiliation(s)
- Ji Hyeon Kim
- Department of Biochemistry and Molecular Biology, Seoul National University College of Medicine , Seoul 03080, Korea.,Department of Biomedical Sciences, Seoul National University Graduate School , Seoul 03080, Korea
| | - Eunkyoung Kim
- Department of Biochemistry and Molecular Biology, Seoul National University College of Medicine , Seoul 03080, Korea
| | - Won Hoon Choi
- Department of Biochemistry and Molecular Biology, Seoul National University College of Medicine , Seoul 03080, Korea.,Department of Biomedical Sciences, Seoul National University Graduate School , Seoul 03080, Korea
| | - Jeeyoung Lee
- Department of Biochemistry and Molecular Biology, Seoul National University College of Medicine , Seoul 03080, Korea.,Department of Biomedical Sciences, Seoul National University Graduate School , Seoul 03080, Korea
| | - Jung Hoon Lee
- Department of Biochemistry and Molecular Biology, Seoul National University College of Medicine , Seoul 03080, Korea
| | - Hyojin Lee
- Department of Biomedical Sciences, Seoul National University Graduate School , Seoul 03080, Korea.,Neuroscience Research Institute, Seoul National University College of Medicine , Seoul 03080, Korea
| | - Dong-Eun Kim
- Department of Bioscience and Biotechnology, Konkuk University , Seoul 05029, Korea
| | - Young Ho Suh
- Department of Biomedical Sciences, Seoul National University Graduate School , Seoul 03080, Korea.,Neuroscience Research Institute, Seoul National University College of Medicine , Seoul 03080, Korea
| | - Min Jae Lee
- Department of Biochemistry and Molecular Biology, Seoul National University College of Medicine , Seoul 03080, Korea.,Department of Biomedical Sciences, Seoul National University Graduate School , Seoul 03080, Korea.,Biomedical Research Institutue, Seoul National University Hospital , Seoul 03080, Korea
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48
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Open-gate mutants of the mammalian proteasome show enhanced ubiquitin-conjugate degradation. Nat Commun 2016; 7:10963. [PMID: 26957043 PMCID: PMC4786872 DOI: 10.1038/ncomms10963] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Accepted: 02/04/2016] [Indexed: 12/20/2022] Open
Abstract
When in the closed form, the substrate translocation channel of the proteasome core
particle (CP) is blocked by the convergent N termini of α-subunits. To
probe the role of channel gating in mammalian proteasomes, we deleted the N-terminal
tail of α3; the resulting α3ΔN proteasomes are intact
but hyperactive in the hydrolysis of fluorogenic peptide substrates and the
degradation of polyubiquitinated proteins. Cells expressing the hyperactive
proteasomes show markedly elevated degradation of many established proteasome
substrates and resistance to oxidative stress. Multiplexed quantitative proteomics
revealed ∼200 proteins with reduced levels in the mutant cells. Potentially
toxic proteins such as tau exhibit reduced accumulation and aggregate formation.
These data demonstrate that the CP gate is a key negative regulator of proteasome
function in mammals, and that opening the CP gate may be an effective strategy to
increase proteasome activity and reduce levels of toxic proteins in cells. The proteasome plays a key role in proteostasis by mediating the
degradation of ubiquitinated substrates. Here the authors show that an open-gate mutant
of the proteasome is hyperactive towards a subset of substrates and can effectively
delay the accumulation of toxic protein aggregates.
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49
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Kim D, Lim S, Haque MM, Ryoo N, Hong HS, Rhim H, Lee DE, Chang YT, Lee JS, Cheong E, Kim DJ, Kim YK. Identification of disulfide cross-linked tau dimer responsible for tau propagation. Sci Rep 2015; 5:15231. [PMID: 26470054 PMCID: PMC4606741 DOI: 10.1038/srep15231] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Accepted: 09/11/2015] [Indexed: 01/24/2023] Open
Abstract
Recent evidence suggests that tau aggregates are not only neurotoxic, but also propagate in neurons acting as a seed for native tau aggregation. Prion-like tau transmission is now considered as an important pathogenic mechanism driving the progression of tau pathology in the brain. However, prion-like tau species have not been clearly characterized. To identify infectious tau conformers, here we prepared diverse tau aggregates and evaluated the effect on inducing intracellular tau-aggregation. Among tested, tau dimer containing P301L-mutation is identified as the most infectious form to induce tau pathology. Biochemical analysis reveals that P301L-tau dimer is covalently cross-linked with a disulfide bond. The relatively small and covalently cross-linked tau dimer induced tau pathology efficiently in primary neurons and also in tau-transgenic mice. So far, the importance of tau disulfide cross-linking has been overlooked in the study of tau pathology. Here our results suggested that tau disulfide cross-linking might play critical role in tau propagation by producing structurally stable and small tau conformers.
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Affiliation(s)
- Dohee Kim
- Korea Institute of Science and Technology (KIST), Brain Science Institute, Center for neuro-medicine, Seoul 136-791, South Korea.,Department of Biotechnology, Translational Research Center for Protein Function Control, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, South Korea
| | - Sungsu Lim
- Korea Institute of Science and Technology (KIST), Brain Science Institute, Center for neuro-medicine, Seoul 136-791, South Korea
| | - Md Mamunul Haque
- Korea Institute of Science and Technology (KIST), Brain Science Institute, Center for neuro-medicine, Seoul 136-791, South Korea.,Biological Chemistry, University of Science and Technology (UST), Daejon 305-333, South Korea
| | - Nayeon Ryoo
- Korea Institute of Science and Technology (KIST), Brain Science Institute, Center for Neuroscience, Seoul 136-791, South Korea
| | | | - Hyewhon Rhim
- Korea Institute of Science and Technology (KIST), Brain Science Institute, Center for Neuroscience, Seoul 136-791, South Korea.,Department of Neuroscience, University of Science and Technology (UST), Daejon 305-333, South Korea
| | - Dong-Eun Lee
- Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185, South Korea
| | - Young-Tae Chang
- Department of Chemistry &Med Chem Program, National University of Singapore, 3 Science Drive 2, 117543 Singapore (Singapore).,Singapore BioImaging Consortium, Agency for Science, Technology and Research, 11 Biopolis Way, 138667 Singapore (Singapore)
| | - Jun-Seok Lee
- Korea Institute of Science and Technology (KIST), Molecular Recognition Research Center, Seoul 136-791, South Korea.,Biological Chemistry, University of Science and Technology (UST), Daejon 305-333, South Korea
| | - Eunji Cheong
- Department of Biotechnology, Translational Research Center for Protein Function Control, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, South Korea
| | - Dong Jin Kim
- Korea Institute of Science and Technology (KIST), Brain Science Institute, Center for neuro-medicine, Seoul 136-791, South Korea
| | - Yun Kyung Kim
- Korea Institute of Science and Technology (KIST), Brain Science Institute, Center for neuro-medicine, Seoul 136-791, South Korea.,Biological Chemistry, University of Science and Technology (UST), Daejon 305-333, South Korea
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50
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Monitoring of Intracellular Tau Aggregation Regulated by OGA/OGT Inhibitors. Int J Mol Sci 2015; 16:20212-24. [PMID: 26343633 PMCID: PMC4613198 DOI: 10.3390/ijms160920212] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Revised: 08/12/2015] [Accepted: 08/18/2015] [Indexed: 12/14/2022] Open
Abstract
Abnormal phosphorylation of tau has been considered as a key pathogenic mechanism inducing tau aggregation in multiple neurodegenerative disorders, collectively called tauopathies. Recent evidence showed that tau phosphorylation sites are protected with O-linked β-N-acetylglucosamine (O-GlcNAc) in normal brain. In pathological condition, tau is de-glycosylated and becomes a substrate for kinases. Despite the importance of O-GlcNAcylation in tau pathology, O-GlcNAc transferase (OGT), and an enzyme catalyzing O-GlcNAc to tau, has not been carefully investigated in the context of tau aggregation. Here, we investigated intracellular tau aggregation regulated by BZX2, an inhibitor of OGT. Upon the inhibition of OGT, tau phosphorylation increased 2.0-fold at Ser199 and 1.5-fold at Ser396, resulting in increased tau aggregation. Moreover, the BZX2 induced tau aggregation was efficiently reduced by the treatment of Thiamet G, an inhibitor of O-GlcNAcase (OGA). Our results demonstrated the protective role of OGT in tau aggregation and also suggest the counter-regulatory mechanism of OGA and OGT in tau pathology.
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