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Chen X, Cao Z, Wang Y. Amyotrophic Lateral Sclerosis-Associated Mutants of SOD1 Perturb mRNA Splicing through Aberrant Interactions with SRSF2. Anal Chem 2024; 96:9713-9720. [PMID: 38795036 DOI: 10.1021/acs.analchem.4c01770] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2024]
Abstract
Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder that results in the degeneration of neurons in the brain and spinal cord. Although a substantial number of studies have been conducted, much remains to be learned about the cellular mechanisms underlying ALS. In this study, we employed an engineered ascorbate peroxidase (APEX)-based proximity biotinylation, together with affinity pull-down of the ensuing biotinylated peptides, to investigate the proximity proteomes of human SOD1 and its two ALS-linked mutants, G85R and G93A. We were able to identify 25 common biotinylated peptides with preferential enrichment in the proximity proteomes of SOD1G85R and SOD1G93A over wild-type SOD1. Our coimmunoprecipitation followed by Western blot analyses revealed that one of these proteins, SRSF2, binds more strongly with the two SOD1 mutants than its wild-type counterpart. We also observed aberrant splicing of mRNAs in cells with ectopic expression of the two SOD1 mutants relative to cells expressing the wild-type protein. In addition, the aberrations in splicing elicited by the SOD1 variants were markedly attenuated upon knockdown of SRSF2. Collectively, we uncovered that ALS-liked SOD1G85R and SOD1G93A mutants interact more strongly with SRSF2, where the aberrant interactions perturbed mRNA splicing. Thus, our work offered novel mechanistic insights into the contributions of the ALS-linked SOD1 mutants to disease etiology.
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Affiliation(s)
- Xingyuan Chen
- Environmental Toxicology Graduate Program, University of California, Riverside, California 92502, United States
| | - Zhongwen Cao
- Environmental Toxicology Graduate Program, University of California, Riverside, California 92502, United States
| | - Yinsheng Wang
- Environmental Toxicology Graduate Program, University of California, Riverside, California 92502, United States
- Department of Chemistry, University of California, Riverside, California 92502, United States
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2
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Tsekrekou M, Giannakou M, Papanikolopoulou K, Skretas G. Protein aggregation and therapeutic strategies in SOD1- and TDP-43- linked ALS. Front Mol Biosci 2024; 11:1383453. [PMID: 38855322 PMCID: PMC11157337 DOI: 10.3389/fmolb.2024.1383453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Accepted: 05/02/2024] [Indexed: 06/11/2024] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease with severe socio-economic impact. A hallmark of ALS pathology is the presence of aberrant cytoplasmic inclusions composed of misfolded and aggregated proteins, including both wild-type and mutant forms. This review highlights the critical role of misfolded protein species in ALS pathogenesis, particularly focusing on Cu/Zn superoxide dismutase (SOD1) and TAR DNA-binding protein 43 (TDP-43), and emphasizes the urgent need for innovative therapeutic strategies targeting these misfolded proteins directly. Despite significant advancements in understanding ALS mechanisms, the disease remains incurable, with current treatments offering limited clinical benefits. Through a comprehensive analysis, the review focuses on the direct modulation of the misfolded proteins and presents recent discoveries in small molecules and peptides that inhibit SOD1 and TDP-43 aggregation, underscoring their potential as effective treatments to modify disease progression and improve clinical outcomes.
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Affiliation(s)
- Maria Tsekrekou
- Institute of Chemical Biology, National Hellenic Research Foundation, Athens, Greece
| | - Maria Giannakou
- Institute of Chemical Biology, National Hellenic Research Foundation, Athens, Greece
- Department of Biology, National and Kapodistrian University of Athens, Athens, Greece
| | - Katerina Papanikolopoulou
- Institute for Fundamental Biomedical Research, Biomedical Sciences Research Centre “Alexander Fleming”, Vari, Greece
- ResQ Biotech, Patras Science Park, Rio, Greece
| | - Georgios Skretas
- Institute of Chemical Biology, National Hellenic Research Foundation, Athens, Greece
- ResQ Biotech, Patras Science Park, Rio, Greece
- Institute for Bio-innovation, Biomedical Sciences Research Centre “Alexander Fleming”, Vari, Greece
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3
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Magrì A, Lipari CLR, Caccamo A, Battiato G, Conti Nibali S, De Pinto V, Guarino F, Messina A. AAV-mediated upregulation of VDAC1 rescues the mitochondrial respiration and sirtuins expression in a SOD1 mouse model of inherited ALS. Cell Death Discov 2024; 10:178. [PMID: 38627359 PMCID: PMC11021507 DOI: 10.1038/s41420-024-01949-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Revised: 03/29/2024] [Accepted: 04/08/2024] [Indexed: 04/19/2024] Open
Abstract
Mitochondrial dysfunction represents one of the most common molecular hallmarks of both sporadic and familial forms of amyotrophic lateral sclerosis (ALS), a neurodegenerative disorder caused by the selective degeneration and death of motor neurons. The accumulation of misfolded proteins on and within mitochondria, as observed for SOD1 G93A mutant, correlates with a drastic reduction of mitochondrial respiration and the inhibition of metabolites exchanges, including ADP/ATP and NAD+/NADH, across the Voltage-Dependent Anion-selective Channel 1 (VDAC1), the most abundant channel protein of the outer mitochondrial membrane. Here, we show that the AAV-mediated upregulation of VDAC1 in the spinal cord of transgenic mice expressing SOD1 G93A completely rescues the mitochondrial respiratory profile. This correlates with the increased activity and levels of key regulators of mitochondrial functions and maintenance, namely the respiratory chain Complex I and the sirtuins (Sirt), especially Sirt3. Furthermore, the selective increase of these mitochondrial proteins is associated with an increase in Tom20 levels, the receptor subunit of the TOM complex. Overall, our results indicate that the overexpression of VDAC1 has beneficial effects on ALS-affected tissue by stabilizing the Complex I-Sirt3 axis.
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Affiliation(s)
- Andrea Magrì
- Department of Biological, Geological and Environmental Sciences, University of Catania, Via S. Sofia 97, 95123, Catania, Italy
- we.MitoBiotech s.r.l., C.so Italia 172, 95125, Catania, Italy
| | - Cristiana Lucia Rita Lipari
- Department of Biomedical and Biotechnological Sciences, University of Catania, Via S. Sofia 97, 95123, Catania, Italy
| | - Antonella Caccamo
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, V.le F. Stagno d'Alcontres 32, 98166, Messina, Italy
| | - Giuseppe Battiato
- Department of Biomedical and Biotechnological Sciences, University of Catania, Via S. Sofia 97, 95123, Catania, Italy
| | - Stefano Conti Nibali
- Department of Biomedical and Biotechnological Sciences, University of Catania, Via S. Sofia 97, 95123, Catania, Italy
| | - Vito De Pinto
- we.MitoBiotech s.r.l., C.so Italia 172, 95125, Catania, Italy
- Department of Biomedical and Biotechnological Sciences, University of Catania, Via S. Sofia 97, 95123, Catania, Italy
| | - Francesca Guarino
- we.MitoBiotech s.r.l., C.so Italia 172, 95125, Catania, Italy
- Department of Biomedical and Biotechnological Sciences, University of Catania, Via S. Sofia 97, 95123, Catania, Italy
| | - Angela Messina
- Department of Biological, Geological and Environmental Sciences, University of Catania, Via S. Sofia 97, 95123, Catania, Italy.
- we.MitoBiotech s.r.l., C.so Italia 172, 95125, Catania, Italy.
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4
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Magrì A, Lipari CLR, Risiglione P, Zimbone S, Guarino F, Caccamo A, Messina A. ERK1/2-dependent TSPO overactivation associates with the loss of mitophagy and mitochondrial respiration in ALS. Cell Death Dis 2023; 14:122. [PMID: 36792609 PMCID: PMC9931716 DOI: 10.1038/s41419-023-05643-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 01/31/2023] [Accepted: 02/01/2023] [Indexed: 02/17/2023]
Abstract
Mitochondrial dysfunction and the loss of mitophagy, aimed at recycling irreversibly damaged organelles, contribute to the onset of amyotrophic lateral sclerosis (ALS), a fatal neurodegenerative disease affecting spinal cord motor neurons. In this work, we showed that the reduction of mitochondrial respiration, exactly oxygen flows linked to ATP production and maximal capacity, correlates with the appearance of the most common ALS motor symptoms in a transgenic mouse model expressing SOD1 G93A mutant. This is the result of the equal inhibition in the respiration linked to complex I and II of the electron transport chain, but not their protein levels. Since the overall mitochondrial mass was unvaried, we investigated the expression of the Translocator Protein (TSPO), a small mitochondrial protein whose overexpression was recently linked to the loss of mitophagy in a model of Parkinson's disease. Here we clearly showed that levels of TSPO are significantly increased in ALS mice. Mechanistically, this increase is linked to the overactivation of ERK1/2 pathway and correlates with a decrease in the expression of the mitophagy-related marker Atg12, indicating the occurrence of impairments in the activation of mitophagy. Overall, our work sets out TSPO as a key regulator of mitochondrial homeostasis in ALS.
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Affiliation(s)
- Andrea Magrì
- grid.8158.40000 0004 1757 1969Department of Biological, Geological and Environmental Sciences, University of Catania, Catania, Italy ,we.MitoBiotech S.R.L., C.so Italia 172, Catania, Italy
| | - Cristiana Lucia Rita Lipari
- grid.8158.40000 0004 1757 1969Department of Biomedical and Biotechnological Sciences, University of Catania, Catania, Italy
| | - Pierpaolo Risiglione
- grid.8158.40000 0004 1757 1969Department of Biomedical and Biotechnological Sciences, University of Catania, Catania, Italy
| | - Stefania Zimbone
- grid.5326.20000 0001 1940 4177Istituto di Cristallografia, Consiglio Nazionale delle Ricerche, Section of Catania, Catania, Italy
| | - Francesca Guarino
- we.MitoBiotech S.R.L., C.so Italia 172, Catania, Italy ,grid.8158.40000 0004 1757 1969Department of Biomedical and Biotechnological Sciences, University of Catania, Catania, Italy
| | - Antonella Caccamo
- grid.8158.40000 0004 1757 1969Department of Drug and Health Sciences, University of Catania, Catania, Italy ,grid.10438.3e0000 0001 2178 8421Department of Chemical, Biological, Pharmaceutical Sciences, University of Messina, Messina, Italy
| | - Angela Messina
- Department of Biological, Geological and Environmental Sciences, University of Catania, Catania, Italy. .,we.MitoBiotech S.R.L., C.so Italia 172, Catania, Italy.
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5
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Porras G, Ruiz S, Maestro I, Borrego-Hernández D, Redondo AG, Martínez A, Martín-Requero Á. Functional Characterization of a Familial ALS-Associated Missense TBK1 (p-Arg573Gly) Mutation in Patient-Derived Lymphoblasts. Int J Mol Sci 2023; 24:ijms24032847. [PMID: 36769169 PMCID: PMC9917786 DOI: 10.3390/ijms24032847] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2022] [Revised: 01/27/2023] [Accepted: 01/31/2023] [Indexed: 02/05/2023] Open
Abstract
The goal of this work was to elucidate the pathogenic mechanism of an ALS-associated missense mutation, p.Arg573Gly (R573G), in the TBK1 gene. In particular, we seek to analyze the influence of this variant on the cellular levels and the function of TBK1 in immortalized cells from an ALS patient. The patient (Code# E7) belonged to a Spanish family with autosomal dominant disease manifesting in the sixth decade as either dementia or ALS. Four control individuals without signs of neurological disease were also included in this study. Our results indicate that the R375G TBK1 mutation did not affect the levels of mRNA nor the total TBK1 content; however, we observed a significant decrease in the levels of TBK1 phosphorylation, which is essential for TBK1 activity, as well as a significant reduction in the phosphorylation of p62 and RIPK1, known substrates for TBK1. Lymphoblasts from the R573G TBK1 mutation carrier patient display pathological TDP-43 homeostasis, showing elevated levels of phosphorylated TDP-43 and accumulation of the protein in the cytosolic compartment. In addition, the functional decrease in TBK1 activity observed in the E7 patient did not alter the autophagy flux, but it seems to be enough to increase ROS levels as well as the expression of pro-inflammatory cytokine IL-6.
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Affiliation(s)
- Gracia Porras
- Department of Molecular Biomedicine, Centro de Investigaciones Biológicas, Margarita Salas (CSIC), Ramiro de Maeztu 9, 28040 Madrid, Spain
| | - Silvana Ruiz
- Department of Molecular Biomedicine, Centro de Investigaciones Biológicas, Margarita Salas (CSIC), Ramiro de Maeztu 9, 28040 Madrid, Spain
| | - Inés Maestro
- Department of Structural and Chemical Biology, Centro de Investigaciones Biológicas, Margarita Salas (CSIC), Ramiro de Maeztu 9, 28040 Madrid, Spain
| | | | - Alberto G. Redondo
- ALS Research Lab, Hospital 12 de Octubre Research Institute (i+12), 28041 Madrid, Spain
| | - Ana Martínez
- Department of Structural and Chemical Biology, Centro de Investigaciones Biológicas, Margarita Salas (CSIC), Ramiro de Maeztu 9, 28040 Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), Instituto de Salud Carlos III, 28031 Madrid, Spain
- Correspondence: (A.M.); (Á.M.-R.)
| | - Ángeles Martín-Requero
- Department of Molecular Biomedicine, Centro de Investigaciones Biológicas, Margarita Salas (CSIC), Ramiro de Maeztu 9, 28040 Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), Instituto de Salud Carlos III, 28031 Madrid, Spain
- Correspondence: (A.M.); (Á.M.-R.)
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6
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A liquid-to-solid phase transition of Cu/Zn superoxide dismutase 1 initiated by oxidation and disease mutation. J Biol Chem 2023; 299:102857. [PMID: 36592929 PMCID: PMC9898760 DOI: 10.1016/j.jbc.2022.102857] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2022] [Revised: 12/17/2022] [Accepted: 12/19/2022] [Indexed: 01/01/2023] Open
Abstract
Cu/Zn superoxide dismutase 1 (SOD1) has a high propensity to misfold and form abnormal aggregates when it is subjected to oxidative stress or carries mutations associated with amyotrophic lateral sclerosis. However, the transition from functional soluble SOD1 protein to aggregated SOD1 protein is not completely clear. Here, we propose that liquid-liquid phase separation (LLPS) represents a biophysical process that converts soluble SOD1 into aggregated SOD1. We determined that SOD1 undergoes LLPS in vitro and cells under oxidative stress. Abnormal oxidation of SOD1 induces maturation of droplets formed by LLPS, eventually leading to protein aggregation and fibrosis, and involves residues Cys111 and Trp32. Additionally, we found that pathological mutations in SOD1 associated with ALS alter the morphology and material state of the droplets and promote the transformation of SOD1 to solid-like oligomers which are toxic to nerve cells. Furthermore, the fibrous aggregates formed by both pathways have a concentration-dependent toxicity effect on nerve cells. Thus, these combined results strongly indicate that LLPS may play a major role in pathological SOD1 aggregation, contributing to pathogenesis in ALS.
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7
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Wang LQ, Ma Y, Yuan HY, Zhao K, Zhang MY, Wang Q, Huang X, Xu WC, Dai B, Chen J, Li D, Zhang D, Wang Z, Zou L, Yin P, Liu C, Liang Y. Cryo-EM structure of an amyloid fibril formed by full-length human SOD1 reveals its conformational conversion. Nat Commun 2022; 13:3491. [PMID: 35715417 PMCID: PMC9205981 DOI: 10.1038/s41467-022-31240-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Accepted: 06/09/2022] [Indexed: 11/23/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease. Misfolded Cu, Zn-superoxide dismutase (SOD1) has been linked to both familial and sporadic ALS. SOD1 fibrils formed in vitro share toxic properties with ALS inclusions. Here we produced cytotoxic amyloid fibrils from full-length apo human SOD1 under reducing conditions and determined the atomic structure using cryo-EM. The SOD1 fibril consists of a single protofilament with a left-handed helix. The fibril core exhibits a serpentine fold comprising N-terminal segment (residues 3–55) and C-terminal segment (residues 86–153) with an intrinsic disordered segment. The two segments are zipped up by three salt bridge pairs. By comparison with the structure of apo SOD1 dimer, we propose that eight β-strands (to form a β-barrel) and one α-helix in the subunit of apo SOD1 convert into thirteen β-strands stabilized by five hydrophobic cavities in the SOD1 fibril. Our data provide insights into how SOD1 converts between structurally and functionally distinct states. Misfolded SOD1 has been linked to both familial and sporadic ALS. Here the authors have determined the cryo-EM structure of SOD1 fibrils, providing insights into the conversion of SOD1 from its immature form into an aggregated form during pathogenesis of ALS.
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Affiliation(s)
- Li-Qiang Wang
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, 430072, Wuhan, China.,Wuhan University Shenzhen Research Institute, 518057, Shenzhen, China
| | - Yeyang Ma
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 201210, Shanghai, China.,University of Chinese Academy of Sciences, 100049, Beijing, China
| | - Han-Ye Yuan
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, 430072, Wuhan, China.,Wuhan University Shenzhen Research Institute, 518057, Shenzhen, China
| | - Kun Zhao
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 201210, Shanghai, China.,University of Chinese Academy of Sciences, 100049, Beijing, China
| | - Mu-Ya Zhang
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, 430072, Wuhan, China.,Wuhan University Shenzhen Research Institute, 518057, Shenzhen, China
| | - Qiang Wang
- National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research, Huazhong Agricultural University, 430070, Wuhan, China
| | - Xi Huang
- Department of Neurology, the Second Clinical Medical College, Jinan University (Shenzhen People's Hospital), 518020, Shenzhen, China
| | - Wen-Chang Xu
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, 430072, Wuhan, China
| | - Bin Dai
- Institute of Nano Biomedicine and Engineering, Department of Instrument Science and Engineering, School of Electronic Information and Electrical Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Jie Chen
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, 430072, Wuhan, China.,Wuhan University Shenzhen Research Institute, 518057, Shenzhen, China
| | - Dan Li
- Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Ministry of Education, Bio-X Institutes, Shanghai Jiao Tong University, 200030, Shanghai, China.,Zhangjiang Institute for Advanced Study, Shanghai Jiao Tong University, 200240, Shanghai, China
| | - Delin Zhang
- National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research, Huazhong Agricultural University, 430070, Wuhan, China
| | - Zhengzhi Wang
- School of Civil Engineering, Wuhan University, 430072, Wuhan, China
| | - Liangyu Zou
- Department of Neurology, the Second Clinical Medical College, Jinan University (Shenzhen People's Hospital), 518020, Shenzhen, China
| | - Ping Yin
- National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research, Huazhong Agricultural University, 430070, Wuhan, China
| | - Cong Liu
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 201210, Shanghai, China.
| | - Yi Liang
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, 430072, Wuhan, China. .,Wuhan University Shenzhen Research Institute, 518057, Shenzhen, China.
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8
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Tan HY, Yong YK, Xue YC, Liu H, Furihata T, Shankar EM, Ng CS. cGAS and DDX41-STING mediated intrinsic immunity spreads intercellularly to promote neuroinflammation in SOD1 ALS model. iScience 2022; 25:104404. [PMID: 35712074 PMCID: PMC9194172 DOI: 10.1016/j.isci.2022.104404] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 02/22/2022] [Accepted: 05/10/2022] [Indexed: 11/25/2022] Open
Abstract
Neuroinflammation exacerbates the progression of SOD1-driven amyotrophic lateral sclerosis (ALS), although the underlying mechanisms remain largely unknown. Herein, we demonstrate that misfolded SOD1 (SOD1Mut)-causing ALS results in mitochondrial damage, thus triggering the release of mtDNA and an RNA:DNA hybrid into the cytosol in an mPTP-independent manner to activate IRF3- and IFNAR-dependent type I interferon (IFN-I) and interferon-stimulating genes. The neuronal hyper-IFN-I and pro-inflammatory responses triggered in ALS-SOD1Mut were sufficiently robust to cause a strong physiological outcome in vitro and in vivo. cGAS/DDX41-STING-signaling is amplified in bystander cells through inter-neuronal gap junctions. Our results highlight the importance of a common DNA-sensing pathway between SOD1 and TDP-43 in influencing the progression of ALS. Constitutive basal activation of IFN-I was found in the SOD1-ALS animal model SOD1-ALS damaged mitochondria to release mtDNA and RNA:DNA to activate the STING-pathway Blocking cGAS and STING diminishes neurodegeneration in vivo in the SOD1-ALS model Connexin and pannexin channels are required to propagate neuroinflammation in SOD1-ALS
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Affiliation(s)
- Hong Yien Tan
- Laboratory Centre, Xiamen University Malaysia, Sepang, Selangor, Malaysia.,School of Traditional Chinese Medicine, Xiamen University Malaysia, Sepang, Selangor, Malaysia
| | - Yean Kong Yong
- Laboratory Centre, Xiamen University Malaysia, Sepang, Selangor, Malaysia
| | - Yuan Chao Xue
- Centre for Heart Lung Innovation, St Paul's Hospital, University of British Columbia, Vancouver, BC, Canada.,Department of Pathology and Laboratory of Medicine, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada.,Department of Medicine, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Huitao Liu
- Centre for Heart Lung Innovation, St Paul's Hospital, University of British Columbia, Vancouver, BC, Canada.,Department of Medicine, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Tomomi Furihata
- Laboratory of Clinical Pharmacy and Experimental Therapeutics, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, Tokyo, Japan
| | - Esaki Muthu Shankar
- Infection Biology, Department of Life Sciences, Central University of Tamil Nadu, Thiruvarur, India
| | - Chen Seng Ng
- China-ASEAN College of Marine Sciences, Xiamen University Malaysia, Sepang, Selangor, Malaysia
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9
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Calabrese G, Molzahn C, Mayor T. Protein interaction networks in neurodegenerative diseases: from physiological function to aggregation. J Biol Chem 2022; 298:102062. [PMID: 35623389 PMCID: PMC9234719 DOI: 10.1016/j.jbc.2022.102062] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Revised: 04/26/2022] [Accepted: 05/18/2022] [Indexed: 11/25/2022] Open
Abstract
The accumulation of protein inclusions is linked to many neurodegenerative diseases that typically develop in older individuals, due to a combination of genetic and environmental factors. In rare familial neurodegenerative disorders, genes encoding for aggregation-prone proteins are often mutated. While the underlying mechanism leading to these diseases still remains to be fully elucidated, efforts in the past 20 years revealed a vast network of protein–protein interactions that play a major role in regulating the aggregation of key proteins associated with neurodegeneration. Misfolded proteins that can oligomerize and form insoluble aggregates associate with molecular chaperones and other elements of the proteolytic machineries that are the frontline workers attempting to protect the cells by promoting clearance and preventing aggregation. Proteins that are normally bound to aggregation-prone proteins can become sequestered and mislocalized in protein inclusions, leading to their loss of function. In contrast, mutations, posttranslational modifications, or misfolding of aggregation-prone proteins can lead to gain of function by inducing novel or altered protein interactions, which in turn can impact numerous essential cellular processes and organelles, such as vesicle trafficking and the mitochondria. This review examines our current knowledge of protein–protein interactions involving several key aggregation-prone proteins that are associated with Alzheimer’s disease, Parkinson’s disease, Huntington’s disease, or amyotrophic lateral sclerosis. We aim to provide an overview of the protein interaction networks that play a central role in driving or mitigating inclusion formation, while highlighting some of the key proteomic studies that helped to uncover the extent of these networks.
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Affiliation(s)
- Gaetano Calabrese
- Michael Smith Laboratories, University of British Columbia, V6T 1Z4 Vancouver BC, Canada.
| | - Cristen Molzahn
- Michael Smith Laboratories, University of British Columbia, V6T 1Z4 Vancouver BC, Canada
| | - Thibault Mayor
- Michael Smith Laboratories, University of British Columbia, V6T 1Z4 Vancouver BC, Canada.
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10
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Funada C, Tanino N, Fukaya M, Mikajiri Y, Nishiguchi M, Otake M, Nakasuji H, Kawahito R, Abe F. SOD1 mutations cause hypersensitivity to high-pressure-induced oxidative stress in Saccharomyces cerevisiae. Biochim Biophys Acta Gen Subj 2021; 1866:130049. [PMID: 34728328 DOI: 10.1016/j.bbagen.2021.130049] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 10/04/2021] [Accepted: 10/28/2021] [Indexed: 12/27/2022]
Abstract
Living organisms are subject to various mechanical stressors, such as high hydrostatic pressure. Empirical evidence shows that under high pressure, the oxidative stress response is activated in Saccharomyces cerevisiae. However, the mechanisms involved in its antioxidant systems are unclear. Here, we demonstrate that superoxide dismutase 1 (Sod1) plays a role in resisting high pressure for cell growth. Mutants lacking Sod1 or Ccs1, the copper chaperone for Sod1, displayed growth defects under 25 MPa. Of the various SOD1 mutations associated with familial amyotrophic lateral sclerosis, H46Q and S134N substitutions diminished SOD activity to levels comparable to those of catalytically deficient H63A and null mutants. When these mutant cells were cultured under 25 MPa, their intracellular O2•- levels increased while sod1∆ mutant genome stability was unaffected. The high-pressure sensitive sod1 mutants were also susceptible to sublethal levels of the O2•- generator paraquat. The sod1∆ mutant is known to exhibit methionine and lysine auxotrophy. However, excess methionine addition or overexpression of the lysine permease gene LYP1 did not counteract high-pressure sensitivity in the sod1 mutants, suggesting that their amino acid availability might be intact under 25 MPa. Interestingly, an exclusive localization of Sco2-Sod1 to the intermembrane space (IMS) of mitochondria appeared to partially restore the high-pressure growth ability in the sod1 mutants. Taken these results together, we suggest that high pressure enhances O2•- production and Sod1 within the IMS plays a role in scavenging O2•- allowing the cells to grow under high pressure. BACKGROUND Empirical evidence shows that under high hydrostatic pressure, the oxidative stress response is activated in Saccharomyces cerevisiae. However, the mechanisms involved in its antioxidant systems are unclear. In the current study, we aimed to explore the role of superoxide dismutase 1 (Sod1) in yeast able to grow under high pressure. METHODS Wild type and sod1 mutant cells were cultured in high-pressure chambers under 25 MPa (~250 kg/cm2). The SOD activity in whole cell extracts and 6His-tagged Sod1 recombinant proteins was analyzed using an SOD assay kit. The O2•- generation in cells was estimated by fluorescence staining. RESULTS Mutants lacking Sod1 or Ccs1, the copper chaperone for Sod1, displayed growth defects under 25 MPa. Of the various SOD1 mutations associated with familial amyotrophic lateral sclerosis, H46Q and S134N substitutions diminished SOD activity to levels comparable to those of catalytically deficient H63A and null mutants. The high-pressure sensitive sod1 mutants were also susceptible to sublethal levels of the O2•- generator paraquat. Exclusive localization of Sco2-Sod1 to the intermembrane space (IMS) of mitochondria partially restored the high-pressure growth ability in the sod1 mutants. CONCLUSIONS High pressure enhances O2•- production and Sod1 within the IMS plays a role in scavenging O2•- allowing the cells to grow under high pressure. GENERAL SIGNIFICANCE Unlike external free radical-generating compounds, high-pressure treatment appeared to increase endogenous O2•- levels in yeast cells. Our experimental system offers a unique approach to investigating the physiological responses to mechanical and oxidative stresses in human body.
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Affiliation(s)
- Chisako Funada
- Department of Chemistry and Biological Science, College of Science and Engineering, Aoyama Gakuin University, 5-10-1 Fuchinobe, Chuo-ku, Sagamihara 252-5258, Japan
| | - Nanami Tanino
- Department of Chemistry and Biological Science, College of Science and Engineering, Aoyama Gakuin University, 5-10-1 Fuchinobe, Chuo-ku, Sagamihara 252-5258, Japan
| | - Miina Fukaya
- Department of Chemistry and Biological Science, College of Science and Engineering, Aoyama Gakuin University, 5-10-1 Fuchinobe, Chuo-ku, Sagamihara 252-5258, Japan
| | - Yu Mikajiri
- Department of Chemistry and Biological Science, College of Science and Engineering, Aoyama Gakuin University, 5-10-1 Fuchinobe, Chuo-ku, Sagamihara 252-5258, Japan
| | - Masayoshi Nishiguchi
- Department of Chemistry and Biological Science, College of Science and Engineering, Aoyama Gakuin University, 5-10-1 Fuchinobe, Chuo-ku, Sagamihara 252-5258, Japan
| | - Masato Otake
- Department of Chemistry and Biological Science, College of Science and Engineering, Aoyama Gakuin University, 5-10-1 Fuchinobe, Chuo-ku, Sagamihara 252-5258, Japan
| | - Hiroko Nakasuji
- Department of Chemistry and Biological Science, College of Science and Engineering, Aoyama Gakuin University, 5-10-1 Fuchinobe, Chuo-ku, Sagamihara 252-5258, Japan
| | - Reika Kawahito
- Department of Chemistry and Biological Science, College of Science and Engineering, Aoyama Gakuin University, 5-10-1 Fuchinobe, Chuo-ku, Sagamihara 252-5258, Japan
| | - Fumiyoshi Abe
- Department of Chemistry and Biological Science, College of Science and Engineering, Aoyama Gakuin University, 5-10-1 Fuchinobe, Chuo-ku, Sagamihara 252-5258, Japan.
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11
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Small Hexokinase 1 Peptide against Toxic SOD1 G93A Mitochondrial Accumulation in ALS Rescues the ATP-Related Respiration. Biomedicines 2021; 9:biomedicines9080948. [PMID: 34440152 PMCID: PMC8392704 DOI: 10.3390/biomedicines9080948] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 07/26/2021] [Accepted: 07/31/2021] [Indexed: 12/13/2022] Open
Abstract
Mutations in Cu/Zn Superoxide Dismutase (SOD1) gene represent one of the most common causes of amyotrophic lateral sclerosis (ALS), a fatal neurodegenerative disorder that specifically affects motor neurons (MNs). The dismutase-active SOD1 G93A mutant is responsible for the formation of toxic aggregates onto the mitochondrial surface, using the Voltage-Dependent Anion Channel 1 (VDAC1) as an anchor point to the organelle. VDAC1 is the master regulator of cellular bioenergetics and by binding to hexokinases (HKs) it controls apoptosis. In ALS, however, SOD1 G93A impairs VDAC1 activity and displaces HK1 from mitochondria, promoting organelle dysfunction, and cell death. Using an ALS cell model, we demonstrate that a small synthetic peptide derived from the HK1 sequence (NHK1) recovers the cell viability in a dose–response manner and the defective mitochondrial respiration profile relative to the ADP phosphorylation. This correlates with an unexpected increase of VDAC1 expression and a reduction of SOD1 mutant accumulation at the mitochondrial level. Overall, our findings provide important new insights into the development of therapeutic molecules to fight ALS and help to better define the link between altered mitochondrial metabolism and MNs death in the disease.
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12
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Chen L, Na R, Danae McLane K, Thompson CS, Gao J, Wang X, Ran Q. Overexpression of ferroptosis defense enzyme Gpx4 retards motor neuron disease of SOD1G93A mice. Sci Rep 2021; 11:12890. [PMID: 34145375 PMCID: PMC8213805 DOI: 10.1038/s41598-021-92369-8] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Accepted: 06/08/2021] [Indexed: 01/20/2023] Open
Abstract
Degeneration and death of motor neurons in Amyotrophic Lateral Sclerosis (ALS) are associated with increased lipid peroxidation. Lipid peroxidation is the driver of ferroptosis, an iron-dependent oxidative mode of cell death. However, the importance of ferroptosis in motor neuron degeneration of ALS remains unclear. Glutathione peroxidase 4 (Gpx4) is a key enzyme in suppressing ferroptosis by reducing phospholipid hydroperoxides in membranes. To assess the effect of increased protection against ferroptosis on motor neuron disease, we generated SOD1G93AGPX4 double transgenic mice by cross-breeding GPX4 transgenic mice with SOD1G93A mice, a widely used ALS mouse model. Compared with control SOD1G93A mice, both male and female SOD1G93AGPX4 mice had extended lifespans. SOD1G93AGPX4 mice also showed delayed disease onset and increased motor function, which were correlated with ameliorated spinal motor neuron degeneration and reduced lipid peroxidation. Moreover, cell toxicity induced by SOD1G93A was ameliorated by Gpx4 overexpression and by chemical inhibitors of ferroptosis in vitro. We further found that the anti-ferroptosis defense system in spinal cord tissues of symptomatic SOD1G93A mice and sporadic ALS patients might be compromised due to deficiency of Gpx4. Thus, our results suggest that ferroptosis plays a key role in motor neuron degeneration of ALS.
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Affiliation(s)
- Liuji Chen
- Department of Cell Systems & Anatomy, University of Texas Health San Antonio, 7703 Floyd Curl Dr., San Antonio, TX, 78229, USA
| | - Ren Na
- Department of Cell Systems & Anatomy, University of Texas Health San Antonio, 7703 Floyd Curl Dr., San Antonio, TX, 78229, USA
| | - Kirsten Danae McLane
- Department of Cell Systems & Anatomy, University of Texas Health San Antonio, 7703 Floyd Curl Dr., San Antonio, TX, 78229, USA
| | - Cody Sylvester Thompson
- Department of Cell Systems & Anatomy, University of Texas Health San Antonio, 7703 Floyd Curl Dr., San Antonio, TX, 78229, USA
| | - Ju Gao
- Department of Pharmacology and Experimental Neurosciences, University of Nebraska Medical Center, Omaha, NE, USA
| | - Xinglong Wang
- Department of Pharmacology and Experimental Neurosciences, University of Nebraska Medical Center, Omaha, NE, USA
| | - Qitao Ran
- Department of Cell Systems & Anatomy, University of Texas Health San Antonio, 7703 Floyd Curl Dr., San Antonio, TX, 78229, USA. .,Research Service, South Texas Veterans Health Care System, San Antonio, TX, USA.
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13
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Trist BG, Hilton JB, Hare DJ, Crouch PJ, Double KL. Superoxide Dismutase 1 in Health and Disease: How a Frontline Antioxidant Becomes Neurotoxic. Angew Chem Int Ed Engl 2021; 60:9215-9246. [PMID: 32144830 PMCID: PMC8247289 DOI: 10.1002/anie.202000451] [Citation(s) in RCA: 65] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Indexed: 12/11/2022]
Abstract
Cu/Zn superoxide dismutase (SOD1) is a frontline antioxidant enzyme catalysing superoxide breakdown and is important for most forms of eukaryotic life. The evolution of aerobic respiration by mitochondria increased cellular production of superoxide, resulting in an increased reliance upon SOD1. Consistent with the importance of SOD1 for cellular health, many human diseases of the central nervous system involve perturbations in SOD1 biology. But far from providing a simple demonstration of how disease arises from SOD1 loss-of-function, attempts to elucidate pathways by which atypical SOD1 biology leads to neurodegeneration have revealed unexpectedly complex molecular characteristics delineating healthy, functional SOD1 protein from that which likely contributes to central nervous system disease. This review summarises current understanding of SOD1 biology from SOD1 genetics through to protein function and stability.
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Affiliation(s)
- Benjamin G. Trist
- Brain and Mind Centre and Discipline of PharmacologyThe University of Sydney, CamperdownSydneyNew South Wales2050Australia
| | - James B. Hilton
- Department of Pharmacology and TherapeuticsThe University of MelbourneParkvilleVictoria3052Australia
| | - Dominic J. Hare
- Brain and Mind Centre and Discipline of PharmacologyThe University of Sydney, CamperdownSydneyNew South Wales2050Australia
- School of BioSciencesThe University of MelbourneParkvilleVictoria3052Australia
- Atomic Medicine InitiativeThe University of Technology SydneyBroadwayNew South Wales2007Australia
| | - Peter J. Crouch
- Department of Pharmacology and TherapeuticsThe University of MelbourneParkvilleVictoria3052Australia
| | - Kay L. Double
- Brain and Mind Centre and Discipline of PharmacologyThe University of Sydney, CamperdownSydneyNew South Wales2050Australia
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14
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Trist BG, Hilton JB, Hare DJ, Crouch PJ, Double KL. Superoxide Dismutase 1 in Health and Disease: How a Frontline Antioxidant Becomes Neurotoxic. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202000451] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Benjamin G. Trist
- Brain and Mind Centre and Discipline of Pharmacology The University of Sydney, Camperdown Sydney New South Wales 2050 Australia
| | - James B. Hilton
- Department of Pharmacology and Therapeutics The University of Melbourne Parkville Victoria 3052 Australia
| | - Dominic J. Hare
- Brain and Mind Centre and Discipline of Pharmacology The University of Sydney, Camperdown Sydney New South Wales 2050 Australia
- School of BioSciences The University of Melbourne Parkville Victoria 3052 Australia
- Atomic Medicine Initiative The University of Technology Sydney Broadway New South Wales 2007 Australia
| | - Peter J. Crouch
- Department of Pharmacology and Therapeutics The University of Melbourne Parkville Victoria 3052 Australia
| | - Kay L. Double
- Brain and Mind Centre and Discipline of Pharmacology The University of Sydney, Camperdown Sydney New South Wales 2050 Australia
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15
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Adhikari R, Yang M, Saikia N, Dutta C, Alharbi WFA, Shan Z, Pandey R, Tiwari A. Acetylation of Aβ42 at Lysine 16 Disrupts Amyloid Formation. ACS Chem Neurosci 2020; 11:1178-1191. [PMID: 32207962 PMCID: PMC7605495 DOI: 10.1021/acschemneuro.0c00069] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The residue lysine 28 (K28) is known to form an important salt bridge that stabilizes the Aβ amyloid structure, and acetylation of lysine 28 (K28Ac) slows the Aβ42 fibrillization rate but does not affect fibril morphology. On the other hand, acetylation of lysine 16 (K16Ac) residue greatly diminishes the fibrillization property of Aβ42 peptide and also affects its toxicity. This is due to the fact that lysine 16 acetylated amyloid beta peptide forms amorphous aggregates instead of amyloid fibrils. This is likely a result of increased hydrophobicity of the K16-A21 region due to K16 acetylation, as confirmed by molecular dynamic simulation studies. The calculated results show that the hydrophobic patches of aggregates from acetylated peptides were different when compared to wild-type (WT) peptide. K16Ac and double acetylated (KKAc) peptide aggregates show significantly higher cytotoxicity compared to the WT or K28Ac peptide aggregates alone. However, the heterogeneous mixture of WT and acetylated Aβ42 peptide aggregates exhibited higher free radical formation as well as cytotoxicity, suggesting dynamic interactions between different species could be a critical contributor to Aβ pathology.
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Affiliation(s)
- Rashmi Adhikari
- Department of Chemistry, Michigan Technological University, Houghton, Michigan 49931, United States
| | - Mu Yang
- Department of Chemistry, Michigan Technological University, Houghton, Michigan 49931, United States
| | - Nabanita Saikia
- Department of Physics, Michigan Technological University, Houghton, Michigan 49931, United States
| | - Colina Dutta
- Department of Chemistry, Michigan Technological University, Houghton, Michigan 49931, United States
| | - Wafa F A Alharbi
- Department of Biological Sciences, Michigan Technological University, Houghton, Michigan 49931, United States
| | - Zhiying Shan
- Department of Kinesiology and Integrative Physiology, Michigan Technological University, Houghton, Michigan 49931, United States
| | - Ravindra Pandey
- Department of Physics, Michigan Technological University, Houghton, Michigan 49931, United States
| | - Ashutosh Tiwari
- Department of Chemistry, Michigan Technological University, Houghton, Michigan 49931, United States
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16
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Chantadul V, Wright GSA, Amporndanai K, Shahid M, Antonyuk SV, Washbourn G, Rogers M, Roberts N, Pye M, O'Neill PM, Hasnain SS. Ebselen as template for stabilization of A4V mutant dimer for motor neuron disease therapy. Commun Biol 2020; 3:97. [PMID: 32139772 PMCID: PMC7058017 DOI: 10.1038/s42003-020-0826-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Accepted: 02/13/2020] [Indexed: 11/09/2022] Open
Abstract
Mutations to the gene encoding superoxide dismutase-1 (SOD1) were the first genetic elements discovered that cause motor neuron disease (MND). These mutations result in compromised SOD1 dimer stability, with one of the severest and most common mutations Ala4Val (A4V) displaying a propensity to monomerise and aggregate leading to neuronal death. We show that the clinically used ebselen and related analogues promote thermal stability of A4V SOD1 when binding to Cys111 only. We have developed a A4V SOD1 differential scanning fluorescence-based assay on a C6S mutation background that is effective in assessing suitability of compounds. Crystallographic data show that the selenium atom of these compounds binds covalently to A4V SOD1 at Cys111 at the dimer interface, resulting in stabilisation. This together with chemical amenability for hit expansion of ebselen and its on-target SOD1 pharmacological chaperone activity holds remarkable promise for structure-based therapeutics for MND using ebselen as a template.
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Affiliation(s)
- Varunya Chantadul
- Faculty of Health and Life Sciences, Molecular Biophysics Group, Institute of Integrative Biology, University of Liverpool, Liverpool, L69 7ZB, UK
- Faculty of Dentistry, Department of Anatomy, Mahidol University, Bangkok, 10400, Thailand
| | - Gareth S A Wright
- Faculty of Health and Life Sciences, Molecular Biophysics Group, Institute of Integrative Biology, University of Liverpool, Liverpool, L69 7ZB, UK
| | - Kangsa Amporndanai
- Faculty of Health and Life Sciences, Molecular Biophysics Group, Institute of Integrative Biology, University of Liverpool, Liverpool, L69 7ZB, UK
| | - Munazza Shahid
- Department of Chemistry and Chemical Engineering, Lahore University of Management Sciences, Punjab, 54792, Pakistan
| | - Svetlana V Antonyuk
- Faculty of Health and Life Sciences, Molecular Biophysics Group, Institute of Integrative Biology, University of Liverpool, Liverpool, L69 7ZB, UK
| | - Gina Washbourn
- Faculty of Science and Engineering, Department of Chemistry, University of Liverpool, Liverpool, L69 7ZD, UK
| | - Michael Rogers
- Faculty of Science and Engineering, Department of Chemistry, University of Liverpool, Liverpool, L69 7ZD, UK
| | - Natalie Roberts
- Faculty of Science and Engineering, Department of Chemistry, University of Liverpool, Liverpool, L69 7ZD, UK
| | - Matthew Pye
- Faculty of Science and Engineering, Department of Chemistry, University of Liverpool, Liverpool, L69 7ZD, UK
| | - Paul M O'Neill
- Faculty of Science and Engineering, Department of Chemistry, University of Liverpool, Liverpool, L69 7ZD, UK
| | - S Samar Hasnain
- Faculty of Health and Life Sciences, Molecular Biophysics Group, Institute of Integrative Biology, University of Liverpool, Liverpool, L69 7ZB, UK.
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17
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Draper ACE, Wilson Z, Maile C, Faccenda D, Campanella M, Piercy RJ. Species-specific consequences of an E40K missense mutation in superoxide dismutase 1 (SOD1). FASEB J 2019; 34:458-473. [PMID: 31914665 DOI: 10.1096/fj.201901455r] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Revised: 09/25/2019] [Accepted: 10/08/2019] [Indexed: 11/11/2022]
Abstract
A glutamic acid to lysine (E40K) residue substitution in superoxide dismutase 1 (SOD1) is associated with canine degenerative myelopathy: the only naturally occurring large animal model of amyotrophic lateral sclerosis (ALS). The E40 residue is highly conserved across mammals, except the horse, which naturally carries the (dog mutant) K40 residue. Here we hypothesized that in vitro expression of mutant dog SOD1 would recapitulate features of human ALS (ie, SOD1 protein aggregation, reduced cell viability, perturbations in mitochondrial morphology and membrane potential, reduced ATP production, and increased superoxide ion levels); further, we hypothesized that an equivalent equine SOD1 variant would share similar perturbations in vitro, thereby explain horses' susceptibility to certain neurodegenerative diseases. As in human ALS, expression of mutant dog SOD1 was associated with statistically significant increased aggregate formation, raised superoxide levels (ROS), and altered mitochondrial morphology (increased branching (form factor)), when compared to wild-type dog SOD1-expressing cells. Similar deficits were not detected in cells expressing the equivalent horse SOD1 variant. Our data helps explain the ALS-associated cellular phenotype of dogs expressing the mutant SOD1 protein and reveals that species-specific sequence conservation does not necessarily predict pathogenicity. The work improves understanding of the etiopathogenesis of canine degenerative myelopathy.
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Affiliation(s)
- Alexandra C E Draper
- Comparative Neuromuscular Disease Laboratory, Royal Veterinary College, University of London, London, UK
| | - Zoe Wilson
- Comparative Neuromuscular Disease Laboratory, Royal Veterinary College, University of London, London, UK
| | - Charlotte Maile
- Comparative Neuromuscular Disease Laboratory, Royal Veterinary College, University of London, London, UK
| | - Danilo Faccenda
- Mitochondrial Cell Biology and Pharmaceutical Research Unit, Department of Comparative Biomedical Sciences, Royal Veterinary College, University of London, London, UK
| | - Michelangelo Campanella
- Mitochondrial Cell Biology and Pharmaceutical Research Unit, Department of Comparative Biomedical Sciences, Royal Veterinary College, University of London, London, UK.,University College London Consortium for Mitochondrial Research, University College London, University of London, London, UK
| | - Richard J Piercy
- Comparative Neuromuscular Disease Laboratory, Royal Veterinary College, University of London, London, UK
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18
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Risk Factors and Emerging Therapies in Amyotrophic Lateral Sclerosis. Int J Mol Sci 2019; 20:ijms20112616. [PMID: 31141951 PMCID: PMC6600314 DOI: 10.3390/ijms20112616] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Revised: 05/17/2019] [Accepted: 05/24/2019] [Indexed: 12/11/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal progressive neurodegenerative disease characterized by a permanent degeneration of both upper and lower motor neurons. Many different genes and pathophysiological processes contribute to this disease, however its exact cause remains unclear. Therefore, it is necessary to understand this heterogeneity to find effective treatments. In this review, we focus on selected environmental and genetic risk factors predisposing to ALS and highlight emerging treatments in ALS therapy. Of numerous defective genes associated with ALS, we focus on four principal genes that have been identified as definite causes of ALS: the SOD1 gene, C9orf72, TDP-43, as well as the recently identified TBK1. We also provide up-to-date information on selected environmental factors that have historically been considered as key players in ALS development and pathogenesis. In parallel to our survey of known risk factors, we also discuss emerging ALS stem cell therapies and experimental medicines currently undergoing phase II and III clinical trials.
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19
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Huai J, Zhang Z. Structural Properties and Interaction Partners of Familial ALS-Associated SOD1 Mutants. Front Neurol 2019; 10:527. [PMID: 31164862 PMCID: PMC6536575 DOI: 10.3389/fneur.2019.00527] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Accepted: 05/02/2019] [Indexed: 12/11/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is the most common motor neuron degenerative disease in adults and has also been proven to be a type of conformational disease associated with protein misfolding and dysfunction. To date, more than 150 distinct genes have been found to be associated with ALS, among which Superoxide Dismutase 1 (SOD1) is the first and the most extensively studied gene. It has been well-established that SOD1 mutants-mediated toxicity is caused by a gain-of-function rather than the loss of the detoxifying activity of SOD1. Compared with the clear autosomal dominant inheritance of SOD1 mutants in ALS, the potential toxic mechanisms of SOD1 mutants in motor neurons remain incompletely understood. A large body of evidence has shown that SOD1 mutants may adopt a complex profile of conformations and interact with a wide range of client proteins. Here, in this review, we summarize the fundamental conformational properties and the gained interaction partners of the soluble forms of the SOD1 mutants which have been published in the past decades. Our goal is to find clues to the possible internal links between structural and functional anomalies of SOD1 mutants, as well as the relationships between their exposed epitopes and interaction partners, in order to help reveal and determine potential diagnostic and therapeutic targets.
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Affiliation(s)
- Jisen Huai
- Institute of Psychiatry and Neuroscience, Xinxiang Medical University, Xinxiang, China
| | - Zhongjian Zhang
- Institute of Psychiatry and Neuroscience, Xinxiang Medical University, Xinxiang, China
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20
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Butti Z, Patten SA. RNA Dysregulation in Amyotrophic Lateral Sclerosis. Front Genet 2019; 9:712. [PMID: 30723494 PMCID: PMC6349704 DOI: 10.3389/fgene.2018.00712] [Citation(s) in RCA: 114] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Accepted: 12/20/2018] [Indexed: 12/11/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is the most common adult-onset motor neuron disease and is characterized by the degeneration of upper and lower motor neurons. It has become increasingly clear that RNA dysregulation is a key contributor to ALS pathogenesis. The major ALS genes SOD1, TARDBP, FUS, and C9orf72 are involved in aspects of RNA metabolism processes such as mRNA transcription, alternative splicing, RNA transport, mRNA stabilization, and miRNA biogenesis. In this review, we highlight the current understanding of RNA dysregulation in ALS pathogenesis involving these major ALS genes and discuss the potential of therapeutic strategies targeting disease RNAs for treating ALS.
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Affiliation(s)
- Zoe Butti
- INRS-Institut Armand-Frappier, National Institute of Scientific Research, Laval, QC, Canada
| | - Shunmoogum A Patten
- INRS-Institut Armand-Frappier, National Institute of Scientific Research, Laval, QC, Canada
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21
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ALS-associated missense and nonsense TBK1 mutations can both cause loss of kinase function. Neurobiol Aging 2018; 71:266.e1-266.e10. [PMID: 30033073 PMCID: PMC6983933 DOI: 10.1016/j.neurobiolaging.2018.06.015] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Revised: 06/12/2018] [Accepted: 06/12/2018] [Indexed: 11/23/2022]
Abstract
Mutations in TANK binding kinase 1 (TBK1) have been linked to amyotrophic lateral sclerosis. Some TBK1 variants are nonsense and are predicted to cause disease through haploinsufficiency; however, many other mutations are missense with unknown functional effects. We exome sequenced 699 familial amyotrophic lateral sclerosis patients and identified 16 TBK1 novel or extremely rare protein-changing variants. We characterized a subset of these: p.G217R, p.R357X, and p.C471Y. Here, we show that the p.R357X and p.G217R both abolish the ability of TBK1 to phosphorylate 2 of its kinase targets, IRF3 and optineurin, and to undergo phosphorylation. They both inhibit binding to optineurin and the p.G217R, within the TBK1 kinase domain, reduces homodimerization, essential for TBK1 activation and function. Finally, we show that the proportion of TBK1 that is active (phosphorylated) is reduced in 5 lymphoblastoid cell lines derived from patients harboring heterozygous missense or in-frame deletion TBK1 mutations. We conclude that missense mutations in functional domains of TBK1 impair the binding and phosphorylation of its normal targets, implicating a common loss of function mechanism, analogous to truncation mutations.
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22
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SOD1 Mutations Causing Familial Amyotrophic Lateral Sclerosis Induce Toxicity in Astrocytes: Evidence for Bystander Effects in a Continuum of Astrogliosis. Neurochem Res 2018; 43:166-179. [DOI: 10.1007/s11064-017-2385-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Revised: 08/11/2017] [Accepted: 08/14/2017] [Indexed: 12/18/2022]
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23
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Schmitt ND, Agar JN. Parsing disease-relevant protein modifications from epiphenomena: perspective on the structural basis of SOD1-mediated ALS. JOURNAL OF MASS SPECTROMETRY : JMS 2017; 52:480-491. [PMID: 28558143 PMCID: PMC6002871 DOI: 10.1002/jms.3953] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Revised: 05/23/2017] [Accepted: 05/25/2017] [Indexed: 05/08/2023]
Abstract
Conformational change and modification of proteins are involved in many cellular functions. However, they can also have adverse effects that are implicated in numerous diseases. How structural change promotes disease is generally not well-understood. This perspective illustrates how mass spectrometry (MS), followed by toxicological and epidemiological validation, can discover disease-relevant structural changes and therapeutic strategies. We (with our collaborators) set out to characterize the structural and toxic consequences of disease-associated mutations and post-translational modifications (PTMs) of the cytosolic antioxidant protein Cu/Zn-superoxide dismutase (SOD1). Previous genetic studies discovered >180 different mutations in the SOD1 gene that caused familial (inherited) amyotrophic lateral sclerosis (fALS). Using hydrogen-deuterium exchange with mass spectrometry, we determined that diverse disease-associated SOD1 mutations cause a common structural defect - perturbation of the SOD1 electrostatic loop. X-ray crystallographic studies had demonstrated that this leads to protein aggregation through a specific interaction between the electrostatic loop and an exposed beta-barrel edge strand. Using epidemiology methods, we then determined that decreased SOD1 stability and increased protein aggregation are powerful risk factors for fALS progression, with a combined hazard ratio > 300 (for comparison, a lifetime of smoking is associated with a hazard ratio of ~15 for lung cancer). The resulting structural model of fALS etiology supported the hypothesis that some sporadic ALS (sALS, ~80% of ALS is not associated with a gene defect) could be caused by post-translational protein modification of wild-type SOD1. We developed immunocapture antibodies and high sensitivity top-down MS methods and characterized PTMs of wild-type SOD1 using human tissue samples. Using global hydrogen-deuterium exchange, X-ray crystallography and neurotoxicology, we then characterized toxic and protective subsets of SOD1 PTMs. To cap this perspective, we present proof-of-concept that post-translational modification can cause disease. We show that numerous mutations (N➔D; Q➔E), which result in the same chemical structure as the PTM deamidation, cause multiple diseases. Copyright © 2017 John Wiley & Sons, Ltd.
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Affiliation(s)
- Nicholas D. Schmitt
- Department of Chemistry and Chemical Biology, Northeastern University, Boston, MA, USA
- Barnett Institute of Chemical and Biological Analysis, Northeastern University, Boston, MA, USA
| | - Jeffrey N. Agar
- Department of Chemistry and Chemical Biology, Northeastern University, Boston, MA, USA
- Barnett Institute of Chemical and Biological Analysis, Northeastern University, Boston, MA, USA
- Department of Pharmaceutical Sciences, Northeastern University, Boston, MA, USA
- Correspondence Northeastern University, 360 Huntington Avenue, 140 The Fenway, Room 417, Boston, MA 02115
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24
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Abdolvahabi A, Shi Y, Rasouli S, Croom CM, Aliyan A, Martí AA, Shaw BF. Kaplan-Meier Meets Chemical Kinetics: Intrinsic Rate of SOD1 Amyloidogenesis Decreased by Subset of ALS Mutations and Cannot Fully Explain Age of Disease Onset. ACS Chem Neurosci 2017; 8:1378-1389. [PMID: 28290665 DOI: 10.1021/acschemneuro.7b00029] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Over 150 mutations in SOD1 (superoxide dismutase-1) cause amyotrophic lateral sclerosis (ALS), presumably by accelerating SOD1 amyloidogenesis. Like many nucleation processes, SOD1 fibrillization is stochastic (in vitro), which inhibits the determination of aggregation rates (and obscures whether rates correlate with patient phenotypes). Here, we diverged from classical chemical kinetics and used Kaplan-Meier estimators to quantify the probability of apo-SOD1 fibrillization (in vitro) from ∼103 replicate amyloid assays of wild-type (WT) SOD1 and nine ALS variants. The probability of apo-SOD1 fibrillization (expressed as a Hazard ratio) is increased by certain ALS-linked SOD1 mutations but is decreased or remains unchanged by other mutations. Despite this diversity, Hazard ratios of fibrillization correlated linearly with (and for three mutants, approximately equaled) Hazard ratios of patient survival (R2 = 0.67; Pearson's r = 0.82). No correlation exists between Hazard ratios of fibrillization and age of initial onset of ALS (R2 = 0.09). Thus, Hazard ratios of fibrillization might explain rates of disease progression but not onset. Classical kinetic metrics of fibrillization, i.e., mean lag time and propagation rate, did not correlate as strongly with phenotype (and ALS mutations did not uniformly accelerate mean rate of nucleation or propagation). A strong correlation was found, however, between mean ThT fluorescence at lag time and patient survival (R2 = 0.93); oligomers of SOD1 with weaker fluorescence correlated with shorter survival. This study suggests that SOD1 mutations trigger ALS by altering a property of SOD1 or its oligomers other than the intrinsic rate of amyloid nucleation (e.g., oligomer stability; rates of intercellular propagation; affinity for membrane surfaces; and maturation rate).
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Affiliation(s)
- Alireza Abdolvahabi
- Department of Chemistry and Biochemistry, Baylor University, Waco, Texas 76706, United States
| | - Yunhua Shi
- Department of Chemistry and Biochemistry, Baylor University, Waco, Texas 76706, United States
| | - Sanaz Rasouli
- Department of Chemistry and Biochemistry, Baylor University, Waco, Texas 76706, United States
- Institute of Biomedical Studies, Baylor University, Waco, Texas 76706, United States
| | - Corbin M. Croom
- Department of Chemistry and Biochemistry, Baylor University, Waco, Texas 76706, United States
| | - Amir Aliyan
- Department of Chemistry, Rice University, Houston, Texas 77005, United States
| | - Angel A. Martí
- Department of Chemistry, Rice University, Houston, Texas 77005, United States
- Department of Bioengineering, Rice University, Houston, Texas 77005, United States
| | - Bryan F. Shaw
- Department of Chemistry and Biochemistry, Baylor University, Waco, Texas 76706, United States
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Abstract
ALS is a relentless neurodegenerative disease in which motor neurons are the susceptible neuronal population. Their death results in progressive paresis of voluntary and respiratory muscles. The unprecedented rate of discoveries over the last two decades have broadened our knowledge of genetic causes and helped delineate molecular pathways. Here we critically review ALS epidemiology, genetics, pathogenic mechanisms, available animal models, and iPS cell technologies with a focus on their translational therapeutic potential. Despite limited clinical success in treatments to date, the new discoveries detailed here offer new models for uncovering disease mechanisms as well as novel strategies for intervention.
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Gal J, Kuang L, Barnett KR, Zhu BZ, Shissler SC, Korotkov KV, Hayward LJ, Kasarskis EJ, Zhu H. ALS mutant SOD1 interacts with G3BP1 and affects stress granule dynamics. Acta Neuropathol 2016; 132:563-76. [PMID: 27481264 PMCID: PMC5023729 DOI: 10.1007/s00401-016-1601-x] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2016] [Revised: 07/24/2016] [Accepted: 07/25/2016] [Indexed: 12/11/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease. Mutations in Cu/Zn superoxide dismutase (SOD1) are responsible for approximately 20 % of the familial ALS cases. ALS-causing SOD1 mutants display a gain-of-toxicity phenotype, but the nature of this toxicity is still not fully understood. The Ras GTPase-activating protein-binding protein G3BP1 plays a critical role in stress granule dynamics. Alterations in the dynamics of stress granules have been reported in several other forms of ALS unrelated to SOD1. To our surprise, the mutant G93A SOD1 transgenic mice exhibited pathological cytoplasmic inclusions that co-localized with G3BP1-positive granules in spinal cord motor neurons. The co-localization was also observed in fibroblast cells derived from familial ALS patient carrying SOD1 mutation L144F. Mutant SOD1, unlike wild-type SOD1, interacted with G3BP1 in an RNA-independent manner. Moreover, the interaction is specific for G3BP1 since mutant SOD1 showed little interaction with four other RNA-binding proteins implicated in ALS. The RNA-binding RRM domain of G3BP1 and two particular phenylalanine residues (F380 and F382) are critical for this interaction. Mutant SOD1 delayed the formation of G3BP1- and TIA1-positive stress granules in response to hyperosmolar shock and arsenite treatment in N2A cells. In summary, the aberrant mutant SOD1-G3BP1 interaction affects stress granule dynamics, suggesting a potential link between pathogenic SOD1 mutations and RNA metabolism alterations in ALS.
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Álvarez-Zaldiernas C, Lu J, Zheng Y, Yang H, Blasi J, Solsona C, Holmgren A. Cellular Redox Systems Impact the Aggregation of Cu,Zn Superoxide Dismutase Linked to Familial Amyotrophic Lateral Sclerosis. J Biol Chem 2016; 291:17197-208. [PMID: 27261461 DOI: 10.1074/jbc.m115.708230] [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] [Received: 12/04/2015] [Indexed: 12/11/2022] Open
Abstract
Protein misfolding is implicated in neurodegenerative diseases such as ALS, where mutations of superoxide dismutase 1 (SOD1) account for about 20% of the inherited mutations. Human SOD1 (hSOD1) contains four cysteines, including Cys(57) and Cys(146), which have been linked to protein stability and folding via forming a disulfide bond, and Cys(6) and Cys(111) as free thiols. But the roles of the cellular oxidation-reduction (redox) environment in SOD1 folding and aggregation are not well understood. Here we explore the effects of cellular redox systems on the aggregation of hSOD1 proteins. We found that the known hSOD1 mutations G93A and A4V increased the capability of the thioredoxin and glutaredoxin systems to reduce hSOD1 compared with wild-type hSOD1. Treatment with inhibitors of these redox systems resulted in an increase of hSOD1 aggregates in the cytoplasm of cells transfected with mutants but not in cells transfected with wild-type hSOD1 or those containing a secondary C111G mutation. This aggregation may be coupled to changes in the redox state of the G93A and A4V mutants upon mild oxidative stress. These results strongly suggest that the thioredoxin and glutaredoxin systems are the key regulators for hSOD1 aggregation and may play critical roles in the pathogenesis of ALS.
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Affiliation(s)
- Cristina Álvarez-Zaldiernas
- From the Department of Medical Biochemistry and Biophysics, Karolinska Institutet, 17177, Stockholm, Sweden, the Department of Pathology and Experimental Therapeutics, Faculty of Medicine, Campus Bellvitge, University of Barcelona, Feixa Llarga s/n. Hospitalet de Llobregat, 08907 Barcelona, Spain, and the Bellvitge Biomedical Research Institute, Gran Via de l'Hospitalet, 199-203, L'Hospitalet de Llobregat, Barcelona, 08908 Barcelona, Spain
| | - Jun Lu
- From the Department of Medical Biochemistry and Biophysics, Karolinska Institutet, 17177, Stockholm, Sweden,
| | - Yujuan Zheng
- From the Department of Medical Biochemistry and Biophysics, Karolinska Institutet, 17177, Stockholm, Sweden
| | - Hongqian Yang
- From the Department of Medical Biochemistry and Biophysics, Karolinska Institutet, 17177, Stockholm, Sweden
| | - Juan Blasi
- the Department of Pathology and Experimental Therapeutics, Faculty of Medicine, Campus Bellvitge, University of Barcelona, Feixa Llarga s/n. Hospitalet de Llobregat, 08907 Barcelona, Spain, and the Bellvitge Biomedical Research Institute, Gran Via de l'Hospitalet, 199-203, L'Hospitalet de Llobregat, Barcelona, 08908 Barcelona, Spain
| | - Carles Solsona
- the Department of Pathology and Experimental Therapeutics, Faculty of Medicine, Campus Bellvitge, University of Barcelona, Feixa Llarga s/n. Hospitalet de Llobregat, 08907 Barcelona, Spain, and the Bellvitge Biomedical Research Institute, Gran Via de l'Hospitalet, 199-203, L'Hospitalet de Llobregat, Barcelona, 08908 Barcelona, Spain
| | - Arne Holmgren
- From the Department of Medical Biochemistry and Biophysics, Karolinska Institutet, 17177, Stockholm, Sweden,
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28
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Dorh N, Zhu S, Dhungana KB, Pati R, Luo FT, Liu H, Tiwari A. BODIPY-Based Fluorescent Probes for Sensing Protein Surface-Hydrophobicity. Sci Rep 2015; 5:18337. [PMID: 26679512 PMCID: PMC4683377 DOI: 10.1038/srep18337] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2015] [Accepted: 10/19/2015] [Indexed: 02/07/2023] Open
Abstract
Mapping surface hydrophobic interactions in proteins is key to understanding molecular recognition, biological functions, and is central to many protein misfolding diseases. Herein, we report synthesis and application of new BODIPY-based hydrophobic sensors (HPsensors) that are stable and highly fluorescent for pH values ranging from 7.0 to 9.0. Surface hydrophobic measurements of proteins (BSA, apomyoglobin, and myoglobin) by these HPsensors display much stronger signal compared to 8-anilino-1-naphthalene sulfonic acid (ANS), a commonly used hydrophobic probe; HPsensors show a 10- to 60-fold increase in signal strength for the BSA protein with affinity in the nanomolar range. This suggests that these HPsensors can be used as a sensitive indicator of protein surface hydrophobicity. A first principle approach is used to identify the molecular level mechanism for the substantial increase in the fluorescence signal strength. Our results show that conformational change and increased molecular rigidity of the dye due to its hydrophobic interaction with protein lead to fluorescence enhancement.
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Affiliation(s)
- Nethaniah Dorh
- Department of Chemistry, Michigan Technological University, Houghton, MI 49931, USA
| | - Shilei Zhu
- Department of Chemistry, Michigan Technological University, Houghton, MI 49931, USA
| | - Kamal B. Dhungana
- Department of Physics, Michigan Technological University, Houghton, MI 49931, USA
| | - Ranjit Pati
- Department of Physics, Michigan Technological University, Houghton, MI 49931, USA
| | - Fen-Tair Luo
- Institute of Chemistry, Academia Sinica, Taipei, Taiwan 11529, Republic of China
| | - Haiying Liu
- Department of Chemistry, Michigan Technological University, Houghton, MI 49931, USA
| | - Ashutosh Tiwari
- Department of Chemistry, Michigan Technological University, Houghton, MI 49931, USA
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Abstract
Amyotrophic lateral sclerosis (ALS) is a devastating degenerative disease characterized by progressive loss of motor neurons in the motor cortex, brainstem, and spinal cord. Although defined as a motor disorder, ALS can arise concurrently with frontotemporal lobal dementia (FTLD). ALS begins focally but disseminates to cause paralysis and death. About 10% of ALS cases are caused by gene mutations, and more than 40 ALS-associated genes have been identified. While important questions about the biology of this disease remain unanswered, investigations of ALS genes have delineated pathogenic roles for (a) perturbations in protein stability and degradation, (b) altered homeostasis of critical RNA- and DNA-binding proteins, (c) impaired cytoskeleton function, and (d) non-neuronal cells as modifiers of the ALS phenotype. The rapidity of progress in ALS genetics and the subsequent acquisition of insights into the molecular biology of these genes provide grounds for optimism that meaningful therapies for ALS are attainable.
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30
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Salehi M, Nikkhah M, Ghasemi A, Arab SS. Mitochondrial membrane disruption by aggregation products of ALS-causing superoxide dismutase-1 mutants. Int J Biol Macromol 2015; 75:290-7. [DOI: 10.1016/j.ijbiomac.2015.01.022] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Revised: 01/09/2015] [Accepted: 01/10/2015] [Indexed: 11/24/2022]
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31
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Hilton JB, White AR, Crouch PJ. Metal-deficient SOD1 in amyotrophic lateral sclerosis. J Mol Med (Berl) 2015; 93:481-7. [PMID: 25754173 PMCID: PMC4408375 DOI: 10.1007/s00109-015-1273-3] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Revised: 02/24/2015] [Accepted: 02/25/2015] [Indexed: 12/13/2022]
Abstract
Mutations to the ubiquitous antioxidant enzyme Cu/Zn superoxide dismutase (SOD1) were the first established genetic cause of the fatal, adult-onset neurodegenerative disease amyotrophic lateral sclerosis (ALS). It is widely accepted that these mutations do not cause ALS via a loss of antioxidant function, but elucidating the alternate toxic gain of function has proven to be elusive. Under physiological conditions, SOD1 binds one copper ion and one zinc ion per monomer to form a highly stable and functional homodimer, but there is now ample evidence to indicate aberrant persistence of SOD1 in an intermediate metal-deficient state may contribute to the protein’s involvement in ALS. This review briefly discusses some of the data to support a role for metal-deficient SOD1 in the development of ALS and some of the outcomes from drug development studies that have aimed to modify the symptoms of ALS by targeting the metal state of SOD1. The implications for the metal state of SOD1 in cases of sporadic ALS that do not involve mutant SOD1 are also discussed.
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Affiliation(s)
- James B Hilton
- Department of Pathology, The University of Melbourne, Melbourne, Victoria, 3010, Australia
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32
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Nagano S, Takahashi Y, Yamamoto K, Masutani H, Fujiwara N, Urushitani M, Araki T. A cysteine residue affects the conformational state and neuronal toxicity of mutant SOD1 in mice: relevance to the pathogenesis of ALS. Hum Mol Genet 2015; 24:3427-39. [DOI: 10.1093/hmg/ddv093] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Accepted: 03/09/2015] [Indexed: 12/11/2022] Open
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33
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Keerthana SP, Kolandaivel P. Structural investigation on the electrostatic loop of native and mutated SOD1 and their interaction with therapeutic compounds. RSC Adv 2015. [DOI: 10.1039/c5ra00286a] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The electrostatic loop of the native and mutated SOD1 protein with single point mutation in the loop is subjected to MD simulation. The structure and electrostatic properties of the native and mutated loops before/after interacting with small compounds are compared.
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Affiliation(s)
- S. P. Keerthana
- Department of Physics
- Bharathiar University
- Coimbatore
- India-641 046
| | - P. Kolandaivel
- Department of Physics
- Bharathiar University
- Coimbatore
- India-641 046
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34
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Zhao D, Zhang S, Meng Y, Xiongwei D, Zhang D, Liang Y, Wang L, Liu C. Polyanion binding accelerates the formation of stable and low-toxic aggregates of ALS-linked SOD1 mutant A4V. Proteins 2014; 82:3356-72. [PMID: 25220364 DOI: 10.1002/prot.24691] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2014] [Revised: 09/04/2014] [Accepted: 09/10/2014] [Indexed: 12/16/2022]
Abstract
The toxic property thus far shared by both ALS-linked SOD1 variants and wild-type SOD1 is an increased propensity to aggregation. However, whether SOD1 oligomers or aggregates are toxic to cells remains to be well defined. Moreover, how the toxic SOD1 species are removed from intra- and extracellular environments also needs to be further explored. The DNA binding has been shown to be capable of accelerating the aggregatio\n of wild-type and oxidized SOD1 forms under acidic and neutral conditions. In this study, we explore the binding of DNA and heparin, two types of essential life polyanions, to A4V, an ALS-linked SOD1 mutant, under acidic conditions, and its consequences. The polyanion binding alters the A4V conformation, neutralizes its local positive charges, and increases its local concentrations along the polyanion chain, which are sufficient to lead to acceleration of the pH-dependent A4V aggregation. The accelerated aggregation, which is ascribed to the polyanion binding-mediated removal or shortening of the lag phase in aggregation, contributes to the formation of amorphous A4V nanoparticles. The prolonged incubation with polyanions not only results in the complete conversion of likely soluble toxic A4V oligomers into non- and low-toxic SDS-resistant aggregates, but also increases their stability. Although this is only an initial step toward reducing the toxicity of SOD1 mutants, the accelerating role of polyanions in protein aggregation might become one of the rapid pathways that remove toxic forms of SOD1 mutants from intra- and extracellular environments.
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Affiliation(s)
- Dan Zhao
- Key Laboratory of Pesticide & Chemical Biology, Ministry of Education and School of Chemistry, Central China Normal University, Wuhan, 430079, China
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35
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Solsona C, Kahn TB, Badilla CL, Álvarez-Zaldiernas C, Blasi J, Fernandez JM, Alegre-Cebollada J. Altered thiol chemistry in human amyotrophic lateral sclerosis-linked mutants of superoxide dismutase 1. J Biol Chem 2014; 289:26722-26732. [PMID: 25096579 DOI: 10.1074/jbc.m114.565333] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Neurodegenerative diseases share a common characteristic, the presence of intracellular or extracellular deposits of protein aggregates in nervous tissues. Amyotrophic Lateral Sclerosis (ALS) is a severe and fatal neurodegenerative disorder, which affects preferentially motoneurons. Changes in the redox state of superoxide dismutase 1 (SOD1) are associated with the onset and development of familial forms of ALS. In human SOD1 (hSOD1), a conserved disulfide bond and two free cysteine residues can engage in anomalous thiol/disulfide exchange resulting in non-native disulfides, a hallmark of ALS that is related to protein misfolding and aggregation. Because of the many competing reaction pathways, traditional bulk techniques fall short at quantifying individual thiol/disulfide exchange reactions. Here, we adapt recently developed single-bond chemistry techniques to study individual disulfide isomerization reactions in hSOD1. Mechanical unfolding of hSOD1 leads to the formation of a polypeptide loop held by the disulfide. This loop behaves as a molecular jump rope that brings reactive Cys-111 close to the disulfide. Using force-clamp spectroscopy, we monitor nucleophilic attack of Cys-111 at either sulfur of the disulfide and determine the selectivity of the reaction. Disease-causing mutations G93A and A4V show greatly altered reactivity patterns, which may contribute to the progression of familial ALS.
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Affiliation(s)
- Carles Solsona
- Laboratory of Cellular and Molecular Neurobiology, Department of Pathology and Experimental Therapeutics, Faculty of Medicine-Campus Bellvitge, University of Barcelona, Feixa Llarga s/n. Hospitalet de Llobregat, 08907 Barcelona, Spain,; Bellvitge Biomedical Research Institute (IDIBELL), Gran Via de l'Hospitalet, 199-203, L'Hospitalet de Llobregat, Barcelona, 08908 Barcelona, Spain,.
| | - Thomas B Kahn
- Department of Biochemistry and Molecular Biophysics, Columbia University Medical Center, New York, New York 10032,; Department of Biological Sciences, Columbia University, New York, New York 10027, and
| | - Carmen L Badilla
- Department of Biological Sciences, Columbia University, New York, New York 10027, and
| | - Cristina Álvarez-Zaldiernas
- Laboratory of Cellular and Molecular Neurobiology, Department of Pathology and Experimental Therapeutics, Faculty of Medicine-Campus Bellvitge, University of Barcelona, Feixa Llarga s/n. Hospitalet de Llobregat, 08907 Barcelona, Spain,; Bellvitge Biomedical Research Institute (IDIBELL), Gran Via de l'Hospitalet, 199-203, L'Hospitalet de Llobregat, Barcelona, 08908 Barcelona, Spain
| | - Juan Blasi
- Laboratory of Cellular and Molecular Neurobiology, Department of Pathology and Experimental Therapeutics, Faculty of Medicine-Campus Bellvitge, University of Barcelona, Feixa Llarga s/n. Hospitalet de Llobregat, 08907 Barcelona, Spain,; Bellvitge Biomedical Research Institute (IDIBELL), Gran Via de l'Hospitalet, 199-203, L'Hospitalet de Llobregat, Barcelona, 08908 Barcelona, Spain
| | - Julio M Fernandez
- Department of Biological Sciences, Columbia University, New York, New York 10027, and
| | - Jorge Alegre-Cebollada
- Department of Biological Sciences, Columbia University, New York, New York 10027, and; Vascular Biology and Inflammation Department, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Cl. Melchor Fernández Almagro 3, 28029 Madrid, Spain
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36
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Vonk WIM, Kakkar V, Bartuzi P, Jaarsma D, Berger R, Hofker MH, Klomp LWJ, Wijmenga C, Kampinga HH, van de Sluis B. The Copper Metabolism MURR1 domain protein 1 (COMMD1) modulates the aggregation of misfolded protein species in a client-specific manner. PLoS One 2014; 9:e92408. [PMID: 24691167 PMCID: PMC3972230 DOI: 10.1371/journal.pone.0092408] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2013] [Accepted: 02/21/2014] [Indexed: 01/27/2023] Open
Abstract
The Copper Metabolism MURR1 domain protein 1 (COMMD1) is a protein involved in multiple cellular pathways, including copper homeostasis, NF-κB and hypoxia signalling. Acting as a scaffold protein, COMMD1 mediates the levels, stability and proteolysis of its substrates (e.g. the copper-transporters ATP7B and ATP7A, RELA and HIF-1α). Recently, we established an interaction between the Cu/Zn superoxide dismutase 1 (SOD1) and COMMD1, resulting in a decreased maturation and activation of SOD1. Mutations in SOD1, associated with the progressive neurodegenerative disorder Amyotrophic Lateral Sclerosis (ALS), cause misfolding and aggregation of the mutant SOD1 (mSOD1) protein. Here, we identify COMMD1 as a novel regulator of misfolded protein aggregation as it enhances the formation of mSOD1 aggregates upon binding. Interestingly, COMMD1 co-localizes to the sites of mSOD1 inclusions and forms high molecular weight complexes in the presence of mSOD1. The effect of COMMD1 on protein aggregation is client-specific as, in contrast to mSOD1, COMMD1 decreases the abundance of mutant Parkin inclusions, associated with Parkinson’s disease. Aggregation of a polyglutamine-expanded Huntingtin, causative of Huntington’s disease, appears unaltered by COMMD1. Altogether, this study offers new research directions to expand our current knowledge on the mechanisms underlying aggregation disease pathologies.
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Affiliation(s)
- Willianne I. M. Vonk
- University Medical Center Utrecht, Department of Metabolic and Endocrine Diseases, and Netherlands Metabolomics Center, Utrecht, the Netherlands
- University Medical Center Utrecht, Complex Genetics Section, Utrecht, the Netherlands
| | - Vaishali Kakkar
- University of Groningen, University Medical Center Groningen, Department of Cell Biology, Groningen, the Netherlands
| | - Paulina Bartuzi
- University of Groningen, University Medical Center Groningen, Molecular Genetics, Groningen, the Netherlands
| | - Dick Jaarsma
- Erasmus Medical Center, Department of Neuroscience, Rotterdam, the Netherlands
| | - Ruud Berger
- University Medical Center Utrecht, Department of Metabolic and Endocrine Diseases, and Netherlands Metabolomics Center, Utrecht, the Netherlands
| | - Marten H. Hofker
- University of Groningen, University Medical Center Groningen, Molecular Genetics, Groningen, the Netherlands
| | - Leo W. J. Klomp
- University Medical Center Utrecht, Department of Metabolic and Endocrine Diseases, and Netherlands Metabolomics Center, Utrecht, the Netherlands
| | - Cisca Wijmenga
- University Medical Center Utrecht, Complex Genetics Section, Utrecht, the Netherlands
- University of Groningen, University Medical Center Groningen, Department of Genetics, Groningen, the Netherlands
| | - Harm H. Kampinga
- University of Groningen, University Medical Center Groningen, Department of Cell Biology, Groningen, the Netherlands
| | - Bart van de Sluis
- University of Groningen, University Medical Center Groningen, Molecular Genetics, Groningen, the Netherlands
- * E-mail:
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Redler RL, Shirvanyants D, Dagliyan O, Ding F, Kim DN, Kota P, Proctor EA, Ramachandran S, Tandon A, Dokholyan NV. Computational approaches to understanding protein aggregation in neurodegeneration. J Mol Cell Biol 2014; 6:104-15. [PMID: 24620031 DOI: 10.1093/jmcb/mju007] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The generation of toxic non-native protein conformers has emerged as a unifying thread among disorders such as Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis. Atomic-level detail regarding dynamical changes that facilitate protein aggregation, as well as the structural features of large-scale ordered aggregates and soluble non-native oligomers, would contribute significantly to current understanding of these complex phenomena and offer potential strategies for inhibiting formation of cytotoxic species. However, experimental limitations often preclude the acquisition of high-resolution structural and mechanistic information for aggregating systems. Computational methods, particularly those combine both all-atom and coarse-grained simulations to cover a wide range of time and length scales, have thus emerged as crucial tools for investigating protein aggregation. Here we review the current state of computational methodology for the study of protein self-assembly, with a focus on the application of these methods toward understanding of protein aggregates in human neurodegenerative disorders.
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Affiliation(s)
- Rachel L Redler
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
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Rotunno MS, Bosco DA. An emerging role for misfolded wild-type SOD1 in sporadic ALS pathogenesis. Front Cell Neurosci 2013; 7:253. [PMID: 24379756 PMCID: PMC3863749 DOI: 10.3389/fncel.2013.00253] [Citation(s) in RCA: 167] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2013] [Accepted: 11/25/2013] [Indexed: 12/12/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder that targets motor neurons, leading to paralysis and death within a few years of disease onset. While several genes have been linked to the inheritable, or familial, form of ALS, much less is known about the cause(s) of sporadic ALS, which accounts for ~90% of ALS cases. Due to the clinical similarities between familial and sporadic ALS, it is plausible that both forms of the disease converge on a common pathway and, therefore, involve common factors. Recent evidence suggests the Cu,Zn-superoxide dismutase (SOD1) protein to be one such factor that is common to both sporadic and familial ALS. In 1993, mutations were uncovered in SOD1 that represent the first known genetic cause of familial ALS. While the exact mechanism of mutant-SOD1 toxicity is still not known today, most evidence points to a gain of toxic function that stems, at least in part, from the propensity of this protein to misfold. In the wild-type SOD1 protein, non-genetic perturbations such as metal depletion, disruption of the quaternary structure, and oxidation, can also induce SOD1 to misfold. In fact, these aforementioned post-translational modifications cause wild-type SOD1 to adopt a “toxic conformation” that is similar to familial ALS-linked SOD1 variants. These observations, together with the detection of misfolded wild-type SOD1 within human post-mortem sporadic ALS samples, have been used to support the controversial hypothesis that misfolded forms of wild-type SOD1 contribute to sporadic ALS pathogenesis. In this review, we present data from the literature that both support and contradict this hypothesis. We also discuss SOD1 as a potential therapeutic target for both familial and sporadic ALS.
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Affiliation(s)
- Melissa S Rotunno
- Department of Neurology, University of Massachusetts Medical Center Worcester, MA, USA
| | - Daryl A Bosco
- Department of Neurology, University of Massachusetts Medical Center Worcester, MA, USA
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Lin PY, Simon SM, Koh WK, Folorunso O, Umbaugh CS, Pierce A. Heat shock factor 1 over-expression protects against exposure of hydrophobic residues on mutant SOD1 and early mortality in a mouse model of amyotrophic lateral sclerosis. Mol Neurodegener 2013; 8:43. [PMID: 24256636 PMCID: PMC3907013 DOI: 10.1186/1750-1326-8-43] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2013] [Accepted: 11/11/2013] [Indexed: 12/13/2022] Open
Abstract
Background Mutations in the Cu/Zn superoxide dismutase gene (SOD1) are responsible for 20% of familial forms of amyotrophic lateral sclerosis (ALS), and mutant SOD1 has been shown to have increased surface hydrophobicity in vitro. Mutant SOD1 may adopt a complex array of conformations with varying toxicity in vivo. We have used a novel florescence-based proteomic assay using 4,4’-bis-1-anilinonaphthalene-8-sulfonate (bisANS) to assess the surface hydrophobicity, and thereby distinguish between different conformations, of SOD1and other proteins in situ. Results Covalent bisANS labeling of spinal cord extracts revealed that alterations in surface hydrophobicity of H46R/H48Q mutations in SOD1 provoke formation of high molecular weight SOD1 species with lowered solubility, likely due to increased exposure of hydrophobic surfaces. BisANS was docked on the H46R/H48Q SOD1 structure at the disordered copper binding and electrostatic loops of mutant SOD1, but not non-mutant WT SOD1. 16 non-SOD1 proteins were also identified that exhibited altered surface hydrophobicity in the H46R/H48Q mutant mouse model of ALS, including proteins involved in energy metabolism, cytoskeleton, signaling, and protein quality control. Heat shock proteins (HSPs) were also enriched in the detergent-insoluble fractions with SOD1. Given that chaperones recognize proteins with exposed hydrophobic surfaces as substrates and the importance of protein homeostasis in ALS, we crossed SOD1 H46R/H48Q mutant mice with mice over-expressing the heat shock factor 1 (HSF1) transcription factor. Here we showed that HSF1 over-expression in H46R/H48Q ALS mice enhanced proteostasis as evidenced by increased expression of HSPs in motor neurons and astrocytes and increased solubility of mutant SOD1. HSF1 over-expression significantly reduced body weight loss, delayed ALS disease onset, decreases cases of early disease, and increased survival for the 25th percentile in an H46R/H48Q SOD1 background. HSF1 overexpression did not affect macroautophagy in the ALS background, but was associated with maintenance of carboxyl terminus of Hsp70 interacting protein (CHIP) expression which declined in H46R/H48Q mice. Conclusion Our results uncover the potential importance of changes in protein surface hydrophobicity of SOD1 and other non-SOD1 proteins in ALS, and how strategies that activate HSF1 are valid therapies for ALS and other age-associated proteinopathies.
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Affiliation(s)
- Pei-Yi Lin
- Department of Biochemistry & Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555, USA.
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Cristóvão JS, Leal SS, Cardoso I, Gomes CM. Small molecules present in the cerebrospinal fluid metabolome influence superoxide dismutase 1 aggregation. Int J Mol Sci 2013; 14:19128-45. [PMID: 24048249 PMCID: PMC3794824 DOI: 10.3390/ijms140919128] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2013] [Revised: 08/28/2013] [Accepted: 08/30/2013] [Indexed: 12/13/2022] Open
Abstract
Superoxide dismutase 1 (SOD1) aggregation is one of the pathological markers of amyotrophic lateral sclerosis (ALS), a fatal neurodegenerative disorder. The underlying molecular grounds of SOD1 pathologic aggregation remains obscure as mutations alone are not exclusively the cause for the formation of protein inclusions. Thus, other components in the cell environment likely play a key role in triggering SOD1 toxic aggregation in ALS. Recently, it was found that ALS patients present a specific altered metabolomic profile in the cerebrospinal fluid (CSF) where SOD1 is also present and potentially interacts with metabolites. Here we have investigated how some of these small molecules affect apoSOD1 structure and aggregation propensity. Our results show that as co-solvents, the tested small molecules do not affect apoSOD1 thermal stability but do influence its tertiary interactions and dynamics, as evidenced by combined biophysical analysis and proteolytic susceptibility. Moreover, these compounds influence apoSOD1 aggregation, decreasing nucleation time and promoting the formation of larger and less soluble aggregates, and in some cases polymeric assemblies apparently composed by spherical species resembling the soluble native protein. We conclude that some components of the ALS metabolome that shape the chemical environment in the CSF may influence apoSOD1 conformers and aggregation.
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Affiliation(s)
- Joana S. Cristóvão
- Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Av. da República, EAN, Oeiras 2784-505, Portugal; E-Mails: (J.S.C.); (S.S.L.)
| | - Sónia S. Leal
- Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Av. da República, EAN, Oeiras 2784-505, Portugal; E-Mails: (J.S.C.); (S.S.L.)
| | - Isabel Cardoso
- Molecular Neurobiology Unit, Instituto de Biologia Molecular e Celular, Rua do Campo Alegre, 823, Porto 4150-180, Portugal; E-Mail:
- Escola Superior de Tecnologia da Saúde do Porto, Instituto Politécnico do Porto, Rua Valente Perfeito, 322, Vila Nova de Gaia 4400-330, Portugal
| | - Cláudio M. Gomes
- Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Av. da República, EAN, Oeiras 2784-505, Portugal; E-Mails: (J.S.C.); (S.S.L.)
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +351-21-446-9332; Fax: +351-21-441-1277
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41
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Redox properties of the disulfide bond of human Cu,Zn superoxide dismutase and the effects of human glutaredoxin 1. Biochem J 2012; 446:59-67. [PMID: 22651090 DOI: 10.1042/bj20120075] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The intramolecular disulfide bond in hSOD1 [human SOD1 (Cu,Zn superoxide dismutase 1)] plays a key role in maintaining the protein's stability and quaternary structure. In mutant forms of SOD1 that cause familial ALS (amyotrophic lateral sclerosis), this disulfide bond is more susceptible to chemical reduction, which may lead to destabilization of the dimer and aggregation. During hSOD1 maturation, disulfide formation is catalysed by CCS1 (copper chaperone for SOD1). Previous studies in yeast demonstrate that the yeast GSH/Grx (glutaredoxin) redox system promotes reduction of the hSOD1 disulfide in the absence of CCS1. In the present study, we probe further the interaction between hSOD1, GSH and Grxs to provide mechanistic insight into the redox kinetics and thermodynamics of the hSOD1 disulfide. We demonstrate that hGrx1 (human Grx1) uses a monothiol mechanism to reduce the hSOD1 disulfide, and the GSH/hGrx1 system reduces ALS mutant SOD1 at a faster rate than WT (wild-type) hSOD1. However, redox potential measurements demonstrate that the thermodynamic stability of the disulfide is not consistently lower in ALS mutants compared with WT hSOD1. Furthermore, the presence of metal cofactors does not influence the disulfide redox potential. Overall, these studies suggest that differences in the GSH/hGrx1 reaction rate with WT compared with ALS mutant hSOD1 and not the inherent thermodynamic stability of the hSOD1 disulfide bond may contribute to the greater pathogenicity of ALS mutant hSOD1.
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42
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Mulligan VK, Kerman A, Laister RC, Sharda PR, Arslan PE, Chakrabartty A. Early Steps in Oxidation-Induced SOD1 Misfolding: Implications for Non-Amyloid Protein Aggregation in Familial ALS. J Mol Biol 2012; 421:631-52. [DOI: 10.1016/j.jmb.2012.04.016] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2011] [Revised: 04/12/2012] [Accepted: 04/14/2012] [Indexed: 12/14/2022]
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Prudencio M, Lelie H, Brown HH, Whitelegge JP, Valentine JS, Borchelt DR. A novel variant of human superoxide dismutase 1 harboring amyotrophic lateral sclerosis-associated and experimental mutations in metal-binding residues and free cysteines lacks toxicity in vivo. J Neurochem 2012; 121:475-85. [PMID: 22332887 PMCID: PMC3705958 DOI: 10.1111/j.1471-4159.2012.07690.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Mutations in superoxide dismutase 1 (SOD1) cause familial amyotrophic lateral sclerosis. The Cu-binding capacity of SOD1 has spawned hypotheses that implicate metal-mediated production of reactive species as a potential mechanism of toxicity. In past experiments, we have tested such hypotheses by mutating residues in SOD1 that normally coordinate the binding of Cu, finding that such mutants retain the capacity to induce motor neuron disease. We now describe the lack of disease in mice that express a variant of human SOD1 in which residues that coordinate the binding of Cu and Zn have been mutated (SODMD). SODMD encodes three disease-causing and four experimental mutations that ultimately eliminate all histidines involved in the binding of metals; and includes one disease-causing and one experimental mutation that eliminate secondary metal binding at C6 and C111. We show that the combined effect of these mutations produces a protein that is unstable but does not aggregate on its own, is not toxic, and does not induce disease when co-expressed with high levels of wild-type SOD1. In cell culture models, we determine that the combined mutation of C6 and C111 to G and S, respectively, dramatically reduces the aggregation propensity of SODMD and may account for the lack of toxicity for this mutant.
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Affiliation(s)
- Mercedes Prudencio
- Department of Neuroscience, Center for Translational Research in Neurodegenerative Disease, McKnight Brain Institute, University of Florida, Gainesville, Florida 32610
| | - Herman Lelie
- Department of Chemistry and Biochemistry, University of California at Los Angeles, Los Angeles, CA 90024
| | - Hilda H. Brown
- Department of Neuroscience, Center for Translational Research in Neurodegenerative Disease, McKnight Brain Institute, University of Florida, Gainesville, Florida 32610
| | - Julian P. Whitelegge
- The Pasarow Mass Spectrometry Laboratory, The NPI-Semel Institute, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, CA 90024
| | - Joan S. Valentine
- Department of Chemistry and Biochemistry, University of California at Los Angeles, Los Angeles, CA 90024
| | - David R. Borchelt
- Department of Neuroscience, Center for Translational Research in Neurodegenerative Disease, McKnight Brain Institute, University of Florida, Gainesville, Florida 32610
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44
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Es-Haghi A, Shariatizi S, Ebrahim-Habibi A, Nemat-Gorgani M. Amyloid fibrillation in native and chemically-modified forms of carbonic anhydrase II: role of surface hydrophobicity. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2012; 1824:468-77. [PMID: 22251892 DOI: 10.1016/j.bbapap.2011.12.010] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2011] [Revised: 12/02/2011] [Accepted: 12/25/2011] [Indexed: 10/14/2022]
Abstract
Chemical modification or mutation of proteins may bring about significant changes in the net charge or surface hydrophobicity of a protein structure. Such events may be of major physiological significance and may provide important insights into the genetics of amyloid diseases. In the present study, fibrillation potential of native and chemically-modified forms of bovine carbonic anhydrase II (BCA II) were investigated. Initially, various denaturing conditions including low pH and high temperatures were tested to induce fibrillation. At a low pH of around 2.4, where the protein is totally dissociated, the apo form was found to take up a pre-molten globular (PMG) conformation with the capacity for fibril formation. Upon increasing the pH to around 3.6, a molten globular (MG) form became abundant, forming amorphous aggregates. Charge neutralization and enhancement of hydrophobicity by methylation, acetylation and propionylation of lysine residues appeared very effective in promoting fibrillation of both the apo and holo forms under native conditions, the rates and extents of which were directly proportional to surface hydrophobicity, and influenced by salt concentration and temperature. These modified structures underwent more pronounced fibrillation under native conditions, than the PMG intermediate form, observed under denaturing conditions. The nature of the fibrillation products obtained from intermediate and modified structures were characterized and compared and their possible cytotoxicity determined. Results are discussed in terms of the importance of surface net charge and hydrophobicity in controlling protein aggregation. A discussion on the physiological significance of the observations is also presented.
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Affiliation(s)
- Ali Es-Haghi
- Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran
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45
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Choi I, Song HD, Lee S, Yang YI, Nam JH, Kim SJ, Sung JJ, Kang T, Yi J. Direct observation of defects and increased ion permeability of a membrane induced by structurally disordered Cu/Zn-superoxide dismutase aggregates. PLoS One 2011; 6:e28982. [PMID: 22216152 PMCID: PMC3247219 DOI: 10.1371/journal.pone.0028982] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2011] [Accepted: 11/18/2011] [Indexed: 11/18/2022] Open
Abstract
Interactions between protein aggregates and a cellular membrane have been strongly implicated in many protein conformational diseases. However, such interactions for the case of Cu/Zn superoxide dismutase (SOD1) protein, which is related to fatal neurodegenerative disorder amyotrophic lateral sclerosis (ALS), have not been explored yet. For the first time, we report the direct observation of defect formation and increased ion permeability of a membrane induced by SOD1 aggregates using a supported lipid bilayer and membrane patches of human embryonic kidney cells as model membranes. We observed that aggregated SOD1 significantly induced the formation of defects within lipid membranes and caused the perturbation of membrane permeability, based on surface plasmon resonance spectroscopy, atomic force microscopy and electrophysiology. In the case of apo SOD1 with an unfolded structure, we found that it bound to the lipid membrane surface and slightly perturbed membrane permeability, compared to other folded proteins (holo SOD1 and bovine serum albumin). The changes in membrane integrity and permeability were found to be strongly dependent on the type of proteins and the amount of aggregates present. We expect that the findings presented herein will advance our understanding of the pathway by which structurally disordered SOD1 aggregates exert toxicity in vivo.
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Affiliation(s)
- Inhee Choi
- School of Chemical and Biological Engineering, Institute of Chemical Processes, Seoul National University, Seoul, Republic of Korea
| | - Hyeon Don Song
- School of Chemical and Biological Engineering, Institute of Chemical Processes, Seoul National University, Seoul, Republic of Korea
| | - Suseung Lee
- School of Chemical and Biological Engineering, Institute of Chemical Processes, Seoul National University, Seoul, Republic of Korea
| | - Young In Yang
- School of Chemical and Biological Engineering, Institute of Chemical Processes, Seoul National University, Seoul, Republic of Korea
| | - Joo Hyun Nam
- Department of Physiology, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Sung Joon Kim
- Department of Physiology, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Jung-Joon Sung
- Department of Neurology, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Taewook Kang
- Department of Chemical and Biomolecular Engineering, Sogang University, Seoul, Republic of Korea
- * E-mail: (TK); (JY)
| | - Jongheop Yi
- School of Chemical and Biological Engineering, Institute of Chemical Processes, Seoul National University, Seoul, Republic of Korea
- * E-mail: (TK); (JY)
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46
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Intermolecular transmission of superoxide dismutase 1 misfolding in living cells. Proc Natl Acad Sci U S A 2011; 108:16398-403. [PMID: 21930926 DOI: 10.1073/pnas.1102645108] [Citation(s) in RCA: 201] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Human wild-type superoxide dismutase-1 (wtSOD1) is known to coaggregate with mutant SOD1 in familial amyotrophic lateral sclerosis (FALS), in double transgenic models of FALS, and in cell culture systems, but the structural determinants of this process are unclear. Here we molecularly dissect the effects of intracellular and cell-free obligately misfolded SOD1 mutant proteins on natively structured wild-type SOD1. Expression of the enzymatically inactive, natural familial ALS SOD1 mutations G127X and G85R in human mesenchymal and neural cell lines induces misfolding of wild-type natively structured SOD1, as indicated by: acquisition of immunoreactivity with SOD1 misfolding-specific monoclonal antibodies; markedly enhanced protease sensitivity suggestive of structural loosening; and nonnative disulfide-linked oligomer and multimer formation. Expression of G127X and G85R in mouse cell lines did not induce misfolding of murine wtSOD1, and a species restriction element for human wtSOD1 conversion was mapped to a region of sequence divergence in loop II and β-strand 3 of the SOD1 β-barrel (residues 24-36), then further refined surprisingly to a single tryptophan residue at codon 32 (W32) in human SOD1. Time course experiments enabled by W32 restriction revealed that G127X and misfolded wtSOD1 can induce misfolding of cell-endogenous wtSOD1. Finally, aggregated recombinant G127X is capable of inducing misfolding and protease sensitivity of recombinant human wtSOD1 in a cell-free system containing reducing and chelating agents; cell-free wtSOD1 conversion was also restricted by W32. These observations demonstrate that misfolded SOD1 can induce misfolding of natively structured wtSOD1 in a physiological intracellular milieu, consistent with a direct protein-protein interaction.
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Allen MJ, Lacroix JJ, Ramachandran S, Capone R, Whitlock JL, Ghadge GD, Arnsdorf MF, Roos RP, Lal R. Mutant SOD1 forms ion channel: implications for ALS pathophysiology. Neurobiol Dis 2011; 45:831-8. [PMID: 21930207 DOI: 10.1016/j.nbd.2011.08.031] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2011] [Revised: 08/18/2011] [Accepted: 08/31/2011] [Indexed: 10/17/2022] Open
Abstract
Point mutations in the gene encoding copper-zinc superoxide dismutase (SOD1) impart a gain-of-function to this protein that underlies 20-25% of all familial amyotrophic lateral sclerosis (FALS) cases. However, the specific mechanism of mutant SOD1 toxicity has remained elusive. Using the complementary techniques of atomic force microscopy (AFM), electrophysiology, and cell and molecular biology, here we examine the structure and activity of A4VSOD1, a mutant SOD1. AFM of A4VSOD1 reconstituted in lipid membrane shows discrete tetrameric pore-like structure with outer and inner diameters 12.2 and 3.0nm respectively. Electrophysiological recordings show distinct ionic conductances across bilayer for A4VSOD1 and none for wildtype SOD1. Mouse neuroblastoma cells exposed to A4VSOD1 undergo membrane depolarization and increases in intracellular calcium. These results provide compelling new evidence that a mutant SOD1 is capable of disrupting cellular homeostasis via an unregulated ion channel mechanism. Such a "toxic channel" mechanism presents a new therapeutic direction for ALS research.
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Affiliation(s)
- Michael J Allen
- Center for Nanomedicine and Section of Pulmonary/Critical Care, Department of Medicine, The University of Chicago, Chicago, IL, USA
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Son M, Srikanth U, Puttaparthi K, Luther C, Elliott JL. Biochemical properties and in vivo effects of the SOD1 zinc-binding site mutant (H80G). J Neurochem 2011; 118:891-901. [PMID: 21692800 DOI: 10.1111/j.1471-4159.2011.07360.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
This study presents the initial characterization of transgenic mice with mutations in a primary zinc-binding residue (H80), either alone or with a G93A mutation. H80G;G93A superoxide dismutase 1 (SOD1) transgenic mice developed paralysis with motor neuron loss, and ubiquitin inclusion-type rather than mitochondrial vacuolar pathology. Unlike G93A SOD1-related disease, the course was not accelerated by over-expression of copper chaperone for SOD1. H80G SOD1 transgenic mice did not manifest disease at levels of SOD1 transgene expressed. The H80G mutation altered certain biochemical parameters of both human wild-type SOD1 and G93A SOD1. The H80G mutation does not substantially change the age-dependent accumulation of G93A SOD1 aggregates and hydrophobic species in spinal cord. However, both H80G;G93A SOD1 and H80G SOD1 lack dismutase activity, the ability to form homodimers, and co-operativity with copper chaperone for SOD1, indicating that their dimerization interface is abnormal. The H80G mutation also made SOD1 susceptible to protease digestion. The H80G mutation alters the redox properties of SOD1. G93A SOD1 exists in either reduced or oxidized form, whereas H80G;G93A SOD1 and H80G SOD1 exist only in a reduced state. The inability of SOD1 with an H80G mutation to take part in normal oxidation-reduction reactions has important ramifications for disease mechanisms and pathology in vivo.
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Affiliation(s)
- Marjatta Son
- Department of Neurology, University of Texas, Southwestern Medical Center, Dallas, TX 75390, USA
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Choi I, Yang YI, Song HD, Lee JS, Kang T, Sung JJ, Yi J. Lipid molecules induce the cytotoxic aggregation of Cu/Zn superoxide dismutase with structurally disordered regions. Biochim Biophys Acta Mol Basis Dis 2010; 1812:41-8. [PMID: 20837142 DOI: 10.1016/j.bbadis.2010.09.003] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2010] [Revised: 08/18/2010] [Accepted: 09/07/2010] [Indexed: 02/02/2023]
Abstract
Cu/Zn-superoxide dismutase (SOD1) is present in the cytosol, nucleus, peroxisomes and mitochondrial intermembrane space of human cells. More than 114 variants of human SOD1 have been linked to familial amyotrophic lateral sclerosis (ALS), which is also known as Lou Gehrig's disease. Although the ultimate mechanisms underlying SOD1-mediated cytotoxicity are largely unknown, SOD1 aggregates have been strongly implicated as a common feature in ALS. This study examined the mechanism for the formation of SOD1 aggregates in vitro as well as the nature of its cytotoxicity. The aggregation propensity of SOD1 species was investigated using techniques ranging from circular dichroism spectroscopy to fluorescence dye binding methods, as well as electron microscopic imaging. The aggregation of SOD1 appears to be related to its structural instability. The demetallated (apo)-SOD1 and aggregated SOD1 species, with structurally disordered regions, readily undergo aggregation in the presence of lipid molecules, whereas metallated (holo)-SOD1 does not. The majority of aggregated SOD1s that are induced by lipid molecules have an amorphous morphology and exhibit significant cytotoxicity. The lipid binding propensity of SOD1 was found to be closely related to the changes in surface hydrophobicity of the proteins, even at very low levels, which induced further binding and assembly with lipid molecules. These findings suggest that lipid molecules induce SOD1 aggregation under physiological conditions and exert cytotoxicity, and might provide a possible mechanism for the pathogenesis of ALS.
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Affiliation(s)
- Inhee Choi
- School of Chemical and Biological Engineering, Institute of Chemical Processes, Seoul National University, Seoul 151-742, Korea
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Yin J, Hu S, Jiang W, Liu L, Lan S, Song X, Liu C. DNA-triggered aggregation of copper, zinc superoxide dismutase in the presence of ascorbate. PLoS One 2010; 5:e12328. [PMID: 20808835 PMCID: PMC2924893 DOI: 10.1371/journal.pone.0012328] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2010] [Accepted: 08/02/2010] [Indexed: 11/18/2022] Open
Abstract
The oxidative damage hypothesis proposed for the function gain of copper, zinc superoxide dismutase (SOD1) maintains that both mutant and wild-type (WT) SOD1 catalyze reactions with abnormal substrates that damage cellular components critical for viability of the affected cells. However, whether the oxidative damage of SOD1 is involved in the formation of aggregates rich in SOD1 or not remains elusive. Here, we sought to explore the oxidative aggregation of WT SOD1 exposed to environments containing both ascorbate (Asc) and DNA under neutral conditions. The results showed that the WT SOD1 protein was oxidized in the presence of Asc. The oxidation results in the higher affinity of the modified protein for DNA than that of the unmodified protein. The oxidized SOD1 was observed to be more prone to aggregation than the WT SOD1, and the addition of DNA can significantly accelerate the oxidative aggregation. Moreover, a reasonable relationship can be found between the oxidation, increased hydrophobicity, and aggregation of SOD1 in the presence of DNA. The crucial step in aggregation is neutralization of the positive charges on some SOD1 surfaces by DNA binding. This study might be crucial for understanding molecular forces driving the protein aggregation.
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Affiliation(s)
- Jun Yin
- Key Laboratory of Pesticide and Chemical Biology, Ministry of Education, and School of Chemistry, Central China Normal University, Wuhan, China
| | - Si Hu
- Key Laboratory of Pesticide and Chemical Biology, Ministry of Education, and School of Chemistry, Central China Normal University, Wuhan, China
| | - Wei Jiang
- Key Laboratory of Pesticide and Chemical Biology, Ministry of Education, and School of Chemistry, Central China Normal University, Wuhan, China
| | - Liang Liu
- Key Laboratory of Pesticide and Chemical Biology, Ministry of Education, and School of Chemistry, Central China Normal University, Wuhan, China
| | - Shemin Lan
- Key Laboratory of Pesticide and Chemical Biology, Ministry of Education, and School of Chemistry, Central China Normal University, Wuhan, China
| | - Xuegang Song
- Key Laboratory of Pesticide and Chemical Biology, Ministry of Education, and School of Chemistry, Central China Normal University, Wuhan, China
| | - Changlin Liu
- Key Laboratory of Pesticide and Chemical Biology, Ministry of Education, and School of Chemistry, Central China Normal University, Wuhan, China
- * E-mail:
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