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Ho DM, Shaban M, Mahmood F, Ganguly P, Todeschini L, Van Vactor D, Artavanis-Tsakonas S. cAMP/PKA signaling regulates TDP-43 aggregation and mislocalization. Proc Natl Acad Sci U S A 2024; 121:e2400732121. [PMID: 38838021 PMCID: PMC11181030 DOI: 10.1073/pnas.2400732121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Accepted: 05/03/2024] [Indexed: 06/07/2024] Open
Abstract
Cytoplasmic mislocalization and aggregation of TDP-43 protein are hallmarks of amyotrophic lateral sclerosis (ALS) and are observed in the vast majority of both familial and sporadic cases. How these two interconnected processes are regulated on a molecular level, however, remains enigmatic. Genome-wide screens for modifiers of the ALS-associated genes TDP-43 and FUS have identified the phospholipase D (Pld) pathway as a key regulator of ALS-related phenotypes in the fruit fly Drosophila melanogaster [M. W. Kankel et al., Genetics 215, 747-766 (2020)]. Here, we report the results of our search for downstream targets of the enzymatic product of Pld, phosphatidic acid. We identify two conserved negative regulators of the cAMP/PKA signaling pathway, the phosphodiesterase dunce and the inhibitory subunit PKA-R2, as modifiers of pathogenic phenotypes resulting from overexpression of the Drosophila TDP-43 ortholog TBPH. We show that knockdown of either of these genes results in a mitigation of both TBPH aggregation and mislocalization in larval motor neuron cell bodies, as well as an amelioration of adult-onset motor defects and shortened lifespan induced by TBPH. We determine that PKA kinase activity is downstream of both TBPH and Pld and that overexpression of the PKA target CrebA can rescue TBPH mislocalization. These findings suggest a model whereby increasing cAMP/PKA signaling can ameliorate the molecular and functional effects of pathological TDP-43.
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Affiliation(s)
- Diana M. Ho
- Department of Cell Biology, Harvard Medical School, Boston, MA02115
| | - Muhammad Shaban
- Department of Pathology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA02115
- Department of Pathology, Massachusetts General Hospital, Harvard Medical School, Boston, MA02114
- Cancer Data Science Program, Dana-Farber Cancer Institute, Boston, MA02115
- Cancer Program, Broad Institute of Harvard and MIT, Cambridge, MA02142
| | - Faisal Mahmood
- Department of Pathology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA02115
- Department of Pathology, Massachusetts General Hospital, Harvard Medical School, Boston, MA02114
- Cancer Data Science Program, Dana-Farber Cancer Institute, Boston, MA02115
- Cancer Program, Broad Institute of Harvard and MIT, Cambridge, MA02142
| | - Payel Ganguly
- Department of Cell Biology, Harvard Medical School, Boston, MA02115
| | | | - David Van Vactor
- Department of Cell Biology, Harvard Medical School, Boston, MA02115
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2
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Wei Y, Zhong S, Yang H, Wang X, Lv B, Bian Y, Pei Y, Xu C, Zhao Q, Wu Y, Luo D, Wang F, Sun H, Chen Y. Current therapy in amyotrophic lateral sclerosis (ALS): A review on past and future therapeutic strategies. Eur J Med Chem 2024; 272:116496. [PMID: 38759454 DOI: 10.1016/j.ejmech.2024.116496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Revised: 05/11/2024] [Accepted: 05/11/2024] [Indexed: 05/19/2024]
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease that affects the first and second motoneurons (MNs), associated with muscle weakness, paralysis and finally death. The exact etiology of the disease still remains unclear. Currently, efforts to develop novel ALS treatments which target specific pathomechanisms are being studied. The mechanisms of ALS pathogenesis involve multiple factors, such as protein aggregation, glutamate excitotoxicity, oxidative stress, mitochondrial dysfunction, apoptosis, inflammation etc. Unfortunately, to date, there are only two FDA-approved drugs for ALS, riluzole and edavarone, without curative treatment for ALS. Herein, we give an overview of the many pathways and review the recent discovery and preclinical characterization of neuroprotective compounds. Meanwhile, drug combination and other therapeutic approaches are also reviewed. In the last part, we analyze the reasons of clinical failure and propose perspective on the treatment of ALS in the future.
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Affiliation(s)
- Yuqing Wei
- School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, 210023, China
| | - Sheng Zhong
- School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, 210023, China
| | - Huajing Yang
- School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, 210023, China
| | - Xueqing Wang
- School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, 210023, China
| | - Bingbing Lv
- School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, 210023, China
| | - Yaoyao Bian
- Jiangsu Provincial Engineering Center of TCM External Medication Researching and Industrializing, Nanjing University of Chinese Medicine, Nanjing, 210023, China
| | - Yuqiong Pei
- School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, 210023, China
| | - Chunlei Xu
- School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, 210023, China
| | - Qun Zhao
- School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, 210023, China
| | - Yulan Wu
- School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, 210023, China
| | - Daying Luo
- School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, 210023, China
| | - Fan Wang
- School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, 210023, China
| | - Haopeng Sun
- School of Pharmacy, China Pharmaceutical University, Nanjing, 211198, China.
| | - Yao Chen
- School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, 210023, China.
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3
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Zhu L, Bai D, Wang X, Ou K, Li B, Jia Q, Tan Z, Liang J, He D, Yan S, Wang L, Li S, Li XJ, Yin P. Pathologic TDP-43 downregulates myelin gene expression in the monkey brain. Brain Pathol 2024:e13277. [PMID: 38779803 DOI: 10.1111/bpa.13277] [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: 09/28/2023] [Accepted: 05/02/2024] [Indexed: 05/25/2024] Open
Abstract
Growing evidence indicates that non-neuronal oligodendrocyte plays an important role in Amyotrophic lateral sclerosis (ALS) and other neurodegenerative diseases. In patient's brain, the impaired myelin structure is a pathological feature with the observation of TDP-43 in cytoplasm of oligodendrocyte. However, the mechanism underlying the gain of function by TDP-43 in oligodendrocytes, which are vital for the axonal integrity, remains unclear. Recently, we found that the primate-specific cleavage of truncated TDP-43 fragments occurred in cytoplasm of monkey neural cells. This finding opened up the avenue to investigate the myelin integrity affected by pathogenic TDP-43 in oligodendrocytes. In current study, we demonstrated that the truncated TDP-35 in oligodendrocytes specifically, could lead to the dysfunctional demyelination in corpus callosum of monkey. As a consequence of the interaction of myelin regulatory factor with the accumulated TDP-35 in cytoplasm, the downstream myelin-associated genes expression was downregulated at the transcriptional level. Our study aims to investigate the potential effect on myelin structure injury, affected by the truncated TDP-43 in oligodendrocyte, which provided the additional clues on the gain of function during the progressive pathogenesis and symptoms in TDP-43 related diseases.
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Affiliation(s)
- Longhong Zhu
- Guangdong Key Laboratory of Non-human Primate Research, Key Laboratory of CNS Regeneration (Ministry of Education), Guangdong-Hongkong-Macau Institute of CNS Regeneration, Jinan University, Guangzhou, China
| | - Dazhang Bai
- Guangdong Key Laboratory of Non-human Primate Research, Key Laboratory of CNS Regeneration (Ministry of Education), Guangdong-Hongkong-Macau Institute of CNS Regeneration, Jinan University, Guangzhou, China
- Department of Neurology, Affiliated Hospital of North Sichuan Medical College, Institute of Neurological Diseases, North Sichuan Medical College, Nanchong, China
| | - Xiang Wang
- Guangdong Key Laboratory of Non-human Primate Research, Key Laboratory of CNS Regeneration (Ministry of Education), Guangdong-Hongkong-Macau Institute of CNS Regeneration, Jinan University, Guangzhou, China
| | - Kaili Ou
- Guangdong Key Laboratory of Non-human Primate Research, Key Laboratory of CNS Regeneration (Ministry of Education), Guangdong-Hongkong-Macau Institute of CNS Regeneration, Jinan University, Guangzhou, China
| | - Bang Li
- Guangdong Key Laboratory of Non-human Primate Research, Key Laboratory of CNS Regeneration (Ministry of Education), Guangdong-Hongkong-Macau Institute of CNS Regeneration, Jinan University, Guangzhou, China
| | - Qingqing Jia
- Guangdong Key Laboratory of Non-human Primate Research, Key Laboratory of CNS Regeneration (Ministry of Education), Guangdong-Hongkong-Macau Institute of CNS Regeneration, Jinan University, Guangzhou, China
| | - Zhiqiang Tan
- Department of Medical Imaging, First Affiliated Hospital, Jinan University, Guangzhou, China
| | - Jiahui Liang
- Department of Medical Imaging, State Key Laboratory of Oncology in South China, Guangdong Provincial Clinical Research Center for Cancer, Sun Yat-sen University Cancer Center, Guangzhou, China
| | - Dajian He
- Guangdong Key Laboratory of Non-human Primate Research, Key Laboratory of CNS Regeneration (Ministry of Education), Guangdong-Hongkong-Macau Institute of CNS Regeneration, Jinan University, Guangzhou, China
| | - Sen Yan
- Guangdong Key Laboratory of Non-human Primate Research, Key Laboratory of CNS Regeneration (Ministry of Education), Guangdong-Hongkong-Macau Institute of CNS Regeneration, Jinan University, Guangzhou, China
| | - Lu Wang
- Department of Medical Imaging, First Affiliated Hospital, Jinan University, Guangzhou, China
| | - Shihua Li
- Guangdong Key Laboratory of Non-human Primate Research, Key Laboratory of CNS Regeneration (Ministry of Education), Guangdong-Hongkong-Macau Institute of CNS Regeneration, Jinan University, Guangzhou, China
| | - Xiao-Jiang Li
- Guangdong Key Laboratory of Non-human Primate Research, Key Laboratory of CNS Regeneration (Ministry of Education), Guangdong-Hongkong-Macau Institute of CNS Regeneration, Jinan University, Guangzhou, China
| | - Peng Yin
- Guangdong Key Laboratory of Non-human Primate Research, Key Laboratory of CNS Regeneration (Ministry of Education), Guangdong-Hongkong-Macau Institute of CNS Regeneration, Jinan University, Guangzhou, China
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4
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Lu X, Lu J, Li S, Feng S, Wang Y, Cui L. The Role of Liquid-Liquid Phase Separation in the Accumulation of Pathological Proteins: New Perspectives on the Mechanism of Neurodegenerative Diseases. Aging Dis 2024:AD.2024.0209. [PMID: 38739933 DOI: 10.14336/ad.2024.0209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Accepted: 04/20/2024] [Indexed: 05/16/2024] Open
Abstract
It is widely accepted that living organisms form highly dynamic membrane-less organelles (MLOS) with various functions through phase separation, and the indispensable role that phase separation plays in the mechanisms of normal physiological functions and pathogenesis is gradually becoming clearer. Pathological aggregates, regarded as hallmarks of neurodegenerative diseases, have been revealed to be closely related to aberrant phase separation. Specific proteins are assembled into condensates and transform into insoluble inclusions through aberrant phase separation, contributing to the development of diseases. In this review, we present an overview of the progress of phase separation research, involving its biological mechanisms and the status of research in neurodegenerative diseases, focusing on five main disease-specific proteins, tau, TDP-43, FUS, α-Syn and HTT, and how exactly these proteins reside within dynamic liquid-like compartments and thus turn into solid deposits. Further studies will yield new perspectives for understanding the aggregation mechanisms and potential therapeutic strategies, and future research directions are anticipated.
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Affiliation(s)
- Xingyu Lu
- Guangdong Key Laboratory of Age-Related Cardiac and Cerebral Diseases, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
| | - Jiongtong Lu
- Guangdong Key Laboratory of Age-Related Cardiac and Cerebral Diseases, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
| | - Shengnan Li
- Guangdong Key Laboratory of Age-Related Cardiac and Cerebral Diseases, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
| | - Sifan Feng
- Guangdong Key Laboratory of Age-Related Cardiac and Cerebral Diseases, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
| | - Yan Wang
- Guangdong Key Laboratory of Age-Related Cardiac and Cerebral Diseases, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
| | - Lili Cui
- Guangdong Key Laboratory of Age-Related Cardiac and Cerebral Diseases, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
- The Marine Biomedical Research Institute of Guangdong, School of Ocean and Tropical Medicine, Guangdong Medical University, Zhanjiang, Guangdong, China
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5
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Haider R, Shipley B, Surewicz K, Hinczewski M, Surewicz WK. Pathological C-terminal phosphomimetic substitutions alter the mechanism of liquid-liquid phase separation of TDP-43 low complexity domain. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.21.586202. [PMID: 38585945 PMCID: PMC10996529 DOI: 10.1101/2024.03.21.586202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/09/2024]
Abstract
C-terminally phosphorylated TAR DNA-binding protein of 43 kDa (TDP-43) marks the proteinaceous inclusions that characterize a number of age-related neurodegenerative diseases, including amyotrophic lateral sclerosis, frontotemporal lobar degeneration and Alzheimer's disease. TDP-43 phosphorylation at S403/S404, and especially at S409/S410, is in fact accepted as a biomarker of proteinopathy. These residues are located within the low complexity domain (LCD), which also drives the protein's liquid-liquid phase separation (LLPS). The impact of phosphorylation at these LCD sites on phase separation of the protein is a topic of great interest, as these post-translational modifications and LLPS are both implicated in proteinopathies. Here, we employed a combination of experimental and simulation-based approaches to explore this question on a phosphomimetic model of the TDP-43 LCD. Our turbidity and fluorescence microscopy data show that Ser-to-Asp substitutions at residues S403, S404, S409 and S410 alter the LLPS behavior of TDP-43 LCD. In particular, in contrast to the unmodified protein, the phosphomimetic variants display a biphasic dependence on salt concentration. Through coarse-grained modeling, we find that this biphasic salt dependence is derived from an altered mechanism of phase separation, in which LLPS-driving short-range intermolecular hydrophobic interactions are modulated by long-range attractive electrostatic interactions. Overall, this in vitro and in silico study provides a physiochemical foundation for understanding the impact of pathologically-relevant C-terminal phosphorylation on the LLPS of the TDP-43 in a more complex cellular environment.
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Affiliation(s)
- Raza Haider
- Department of Physiology and Biophysics, Case Western Reserve University, Cleveland, United States
| | - Brandon Shipley
- Department of Physics, Case Western Reserve University, Cleveland, United States
| | - Krystyna Surewicz
- Department of Physiology and Biophysics, Case Western Reserve University, Cleveland, United States
| | - Michael Hinczewski
- Department of Physics, Case Western Reserve University, Cleveland, United States
| | - Witold K Surewicz
- Department of Physiology and Biophysics, Case Western Reserve University, Cleveland, United States
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6
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Berthiaume AA, Reda SM, Kleist KN, Setti SE, Wu W, Johnston JL, Taylor RW, Stein LR, Moebius HJ, Church KJ. ATH-1105, a small-molecule positive modulator of the neurotrophic HGF system, is neuroprotective, preserves neuromotor function, and extends survival in preclinical models of ALS. Front Neurosci 2024; 18:1348157. [PMID: 38389786 PMCID: PMC10881713 DOI: 10.3389/fnins.2024.1348157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Accepted: 01/19/2024] [Indexed: 02/24/2024] Open
Abstract
Introduction Amyotrophic lateral sclerosis (ALS), a progressive and fatal neurodegenerative disorder, primarily affects the motor neurons of the brain and spinal cord. Like other neurodegenerative conditions, ongoing pathological processes such as increased inflammation, excitotoxicity, and protein accumulation contribute to neuronal death. Hepatocyte growth factor (HGF) signaling through the MET receptor promotes pro-survival, anti-apoptotic, and anti-inflammatory effects in multiple cell types, including the neurons and support cells of the nervous system. This pleiotropic system is therefore a potential therapeutic target for treatment of neurodegenerative disorders such as ALS. Here, we test the effects of ATH-1105, a small-molecule positive modulator of the HGF signaling system, in preclinical models of ALS. Methods In vitro, the impact of ATH-1105 on HGF-mediated signaling was assessed via phosphorylation assays for MET, extracellular signal-regulated kinase (ERK), and protein kinase B (AKT). Neuroprotective effects of ATH-1105 were evaluated in rat primary neuron models including spinal motor neurons, motor neuron-astrocyte cocultures, and motor neuron-human muscle cocultures. The anti-inflammatory effects of ATH-1105 were evaluated in microglia- and macrophage-like cell systems exposed to lipopolysaccharide (LPS). In vivo, the impact of daily oral treatment with ATH-1105 was evaluated in Prp-TDP43A315T hemizygous transgenic ALS mice. Results In vitro, ATH-1105 augmented phosphorylation of MET, ERK, and AKT. ATH-1105 attenuated glutamate-mediated excitotoxicity in primary motor neurons and motor neuron- astrocyte cocultures, and had protective effects on motor neurons and neuromuscular junctions in motor neuron-muscle cocultures. ATH-1105 mitigated LPS-induced inflammation in microglia- and macrophage-like cell systems. In vivo, ATH-1105 treatment resulted in improved motor and nerve function, sciatic nerve axon and myelin integrity, and survival in ALS mice. Treatment with ATH-1105 also led to reductions in levels of plasma biomarkers of inflammation and neurodegeneration, along with decreased pathological protein accumulation (phospho-TDP-43) in the sciatic nerve. Additionally, both early intervention (treatment initiation at 1 month of age) and delayed intervention (treatment initiation at 2 months of age) with ATH-1105 produced benefits in this preclinical model of ALS. Discussion The consistent neuroprotective and anti-inflammatory effects demonstrated by ATH-1105 preclinically provide a compelling rationale for therapeutic interventions that leverage the positive modulation of the HGF pathway as a treatment for ALS.
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Affiliation(s)
| | | | | | | | - Wei Wu
- Athira Pharma, Inc., Bothell, WA, United States
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7
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Haider R, Penumutchu S, Boyko S, Surewicz WK. Phosphomimetic substitutions in TDP-43's transiently α-helical region suppress phase separation. Biophys J 2024; 123:361-373. [PMID: 38178578 PMCID: PMC10870169 DOI: 10.1016/j.bpj.2024.01.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 11/10/2023] [Accepted: 01/02/2024] [Indexed: 01/06/2024] Open
Abstract
Phosphorylated TAR DNA-binding protein of 43 kDa (TDP-43) is present within the aggregates of several age-related neurodegenerative disorders, such as amyotrophic lateral sclerosis, frontotemporal lobar degeneration, and Alzheimer's disease, to the point that the presence of phosphorylated TDP-43 is considered a hallmark of some of these diseases. The majority of known TDP-43 phosphorylation sites detected in amyotrophic lateral sclerosis and frontotemporal lobar degeneration patients is located in the low-complexity domain (LCD), the same domain that has been shown to be critical for TDP-43 liquid-liquid phase separation (LLPS). However, the effect of these LCD phosphorylation sites on TDP-43 LLPS has been largely unexplored, and any work that has been done has mainly focused on sites near the C-terminal end of the LCD. Here, we used a phosphomimetic approach to explore the impact of phosphorylation at residues S332 and S333, sites located within the transiently α-helical region of TDP-43 that have been observed to be phosphorylated in disease, on protein LLPS. Our turbidimetry and fluorescence microscopy data demonstrate that these phosphomimetic substitutions greatly suppress LLPS, and solution NMR data strongly suggest that this effect is at least in part due to the loss of α-helical propensity of the phosphomimetic protein variant. We also show that the S332D and S333D substitutions slow TDP-43 LCD droplet aging and fibrillation of the protein. Overall, these findings provide a biophysical basis for understanding the effect of phosphorylation within the transiently α-helical region of TDP-43 LCD on protein LLPS and fibrillation, suggesting that phosphorylation at residues 332 and 333 is not necessarily directly related to the pathogenic process.
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Affiliation(s)
- Raza Haider
- Department of Physiology and Biophysics, Case Western Reserve University, Cleveland, Ohio
| | - Srinivasa Penumutchu
- Northeast Ohio High Field NMR Facility, Case Western Reserve University, Cleveland, Ohio
| | - Solomiia Boyko
- Department of Physiology and Biophysics, Case Western Reserve University, Cleveland, Ohio
| | - Witold K Surewicz
- Department of Physiology and Biophysics, Case Western Reserve University, Cleveland, Ohio.
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8
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Kee TR, Khan SA, Neidhart MB, Masters BM, Zhao VK, Kim YK, McGill Percy KC, Woo JAA. The multifaceted functions of β-arrestins and their therapeutic potential in neurodegenerative diseases. Exp Mol Med 2024; 56:129-141. [PMID: 38212557 PMCID: PMC10834518 DOI: 10.1038/s12276-023-01144-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 10/18/2023] [Accepted: 10/20/2023] [Indexed: 01/13/2024] Open
Abstract
Arrestins are multifunctional proteins that regulate G-protein-coupled receptor (GPCR) desensitization, signaling, and internalization. The arrestin family consists of four subtypes: visual arrestin1, β-arrestin1, β-arrestin2, and visual arrestin-4. Recent studies have revealed the multifunctional roles of β-arrestins beyond GPCR signaling, including scaffolding and adapter functions, and physically interacting with non-GPCR receptors. Increasing evidence suggests that β-arrestins are involved in the pathogenesis of a variety of neurodegenerative diseases, including Alzheimer's disease (AD), frontotemporal dementia (FTD), and Parkinson's disease (PD). β-arrestins physically interact with γ-secretase, leading to increased production and accumulation of amyloid-beta in AD. Furthermore, β-arrestin oligomers inhibit the autophagy cargo receptor p62/SQSTM1, resulting in tau accumulation and aggregation in FTD. In PD, β-arrestins are upregulated in postmortem brain tissue and an MPTP model, and the β2AR regulates SNCA gene expression. In this review, we aim to provide an overview of β-arrestin1 and β-arrestin2, and describe their physiological functions and roles in neurodegenerative diseases. The multifaceted roles of β-arrestins and their involvement in neurodegenerative diseases suggest that they may serve as promising therapeutic targets.
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Affiliation(s)
- Teresa R Kee
- Department of Pathology, CWRU School of Medicine, Cleveland, OH, 44106, USA
- Department of Molecular Medicine, USF Health College of Medicine, Tampa, FL, 33613, USA
| | - Sophia A Khan
- Department of Pathology, CWRU School of Medicine, Cleveland, OH, 44106, USA
| | - Maya B Neidhart
- Department of Pathology, CWRU School of Medicine, Cleveland, OH, 44106, USA
| | - Brianna M Masters
- Department of Pathology, CWRU School of Medicine, Cleveland, OH, 44106, USA
| | - Victoria K Zhao
- Department of Pathology, CWRU School of Medicine, Cleveland, OH, 44106, USA
| | - Yenna K Kim
- Department of Pathology, CWRU School of Medicine, Cleveland, OH, 44106, USA
| | | | - Jung-A A Woo
- Department of Pathology, CWRU School of Medicine, Cleveland, OH, 44106, USA.
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9
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Khalil B, Linsenmeier M, Smith CL, Shorter J, Rossoll W. Nuclear-import receptors as gatekeepers of pathological phase transitions in ALS/FTD. Mol Neurodegener 2024; 19:8. [PMID: 38254150 PMCID: PMC10804745 DOI: 10.1186/s13024-023-00698-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Accepted: 12/13/2023] [Indexed: 01/24/2024] Open
Abstract
Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are fatal neurodegenerative disorders on a disease spectrum that are characterized by the cytoplasmic mislocalization and aberrant phase transitions of prion-like RNA-binding proteins (RBPs). The common accumulation of TAR DNA-binding protein-43 (TDP-43), fused in sarcoma (FUS), and other nuclear RBPs in detergent-insoluble aggregates in the cytoplasm of degenerating neurons in ALS/FTD is connected to nuclear pore dysfunction and other defects in the nucleocytoplasmic transport machinery. Recent advances suggest that beyond their canonical role in the nuclear import of protein cargoes, nuclear-import receptors (NIRs) can prevent and reverse aberrant phase transitions of TDP-43, FUS, and related prion-like RBPs and restore their nuclear localization and function. Here, we showcase the NIR family and how they recognize cargo, drive nuclear import, and chaperone prion-like RBPs linked to ALS/FTD. We also discuss the promise of enhancing NIR levels and developing potentiated NIR variants as therapeutic strategies for ALS/FTD and related neurodegenerative proteinopathies.
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Affiliation(s)
- Bilal Khalil
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, U.S.A
| | - Miriam Linsenmeier
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, U.S.A
| | - Courtney L Smith
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, U.S.A
- Mayo Clinic Graduate School of Biomedical Sciences, Neuroscience Track, Mayo Clinic, Jacksonville, FL, 32224, U.S.A
| | - James Shorter
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, U.S.A..
| | - Wilfried Rossoll
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, U.S.A..
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10
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Zhu L, Deng F, Bai D, Hou J, Jia Q, Zhang C, Ou K, Li S, Li XJ, Yin P. Loss of TDP-43 mediates severe neurotoxicity by suppressing PJA1 gene transcription in the monkey brain. Cell Mol Life Sci 2024; 81:16. [PMID: 38194085 PMCID: PMC11072099 DOI: 10.1007/s00018-023-05066-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Revised: 11/19/2023] [Accepted: 11/27/2023] [Indexed: 01/10/2024]
Abstract
The nuclear loss and cytoplasmic accumulation of TDP-43 (TAR DNA/RNA binding protein 43) are pathological hallmarks of amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD). Previously, we reported that the primate-specific cleavage of TDP-43 accounts for its cytoplasmic mislocalization in patients' brains. This prompted us to investigate further whether and how the loss of nuclear TDP-43 mediates neuropathology in primate brain. In this study, we report that TDP-43 knockdown at the similar effectiveness, induces more damage to neuronal cells in the monkey brain than rodent mouse. Importantly, the loss of TDP-43 suppresses the E3 ubiquitin ligase PJA1 expression in the monkey brain at transcriptional level, but yields an opposite upregulation of PJA1 in the mouse brain. This distinct effect is due to the species-dependent binding of nuclear TDP-43 to the unique promoter sequences of the PJA1 genes. Further analyses reveal that the reduction of PJA1 accelerates neurotoxicity, whereas overexpressing PJA1 diminishes neuronal cell death by the TDP-43 knockdown in vivo. Our findings not only uncover a novel primate-specific neurotoxic contribution to the loss of function theory of TDP-43 proteinopathy, but also underscore a potential therapeutic approach of PJA1 to the loss of nuclear TDP-43.
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Affiliation(s)
- Longhong Zhu
- Guangdong Key Laboratory of Non-Human Primate Research, Guangdong-Hongkong-Macau Institute of CNS Regeneration, Jinan University, Guangzhou, 510632, China
| | - Fuyu Deng
- Guangdong Key Laboratory of Non-Human Primate Research, Guangdong-Hongkong-Macau Institute of CNS Regeneration, Jinan University, Guangzhou, 510632, China
| | - Dazhang Bai
- Guangdong Key Laboratory of Non-Human Primate Research, Guangdong-Hongkong-Macau Institute of CNS Regeneration, Jinan University, Guangzhou, 510632, China
- Department of Neurology, Affiliated Hospital of North Sichuan Medical College, North Sichuan Medical College, Nanchong, 637000, China
- Institute of Neurological Diseases, North Sichuan Medical College, Nanchong, 637000, China
| | - Junqi Hou
- Guangdong Key Laboratory of Non-Human Primate Research, Guangdong-Hongkong-Macau Institute of CNS Regeneration, Jinan University, Guangzhou, 510632, China
| | - Qingqing Jia
- Guangdong Key Laboratory of Non-Human Primate Research, Guangdong-Hongkong-Macau Institute of CNS Regeneration, Jinan University, Guangzhou, 510632, China
| | - Chen Zhang
- Guangdong Key Laboratory of Non-Human Primate Research, Guangdong-Hongkong-Macau Institute of CNS Regeneration, Jinan University, Guangzhou, 510632, China
| | - Kaili Ou
- Guangdong Key Laboratory of Non-Human Primate Research, Guangdong-Hongkong-Macau Institute of CNS Regeneration, Jinan University, Guangzhou, 510632, China
| | - Shihua Li
- Guangdong Key Laboratory of Non-Human Primate Research, Guangdong-Hongkong-Macau Institute of CNS Regeneration, Jinan University, Guangzhou, 510632, China
- Ministry of Education Key Laboratory of CNS Regeneration, Guangdong-Hongkong-Macau Institute of CNS Regeneration, Jinan University, Guangzhou, 510632, China
| | - Xiao-Jiang Li
- Guangdong Key Laboratory of Non-Human Primate Research, Guangdong-Hongkong-Macau Institute of CNS Regeneration, Jinan University, Guangzhou, 510632, China.
- Ministry of Education Key Laboratory of CNS Regeneration, Guangdong-Hongkong-Macau Institute of CNS Regeneration, Jinan University, Guangzhou, 510632, China.
| | - Peng Yin
- Guangdong Key Laboratory of Non-Human Primate Research, Guangdong-Hongkong-Macau Institute of CNS Regeneration, Jinan University, Guangzhou, 510632, China.
- Ministry of Education Key Laboratory of CNS Regeneration, Guangdong-Hongkong-Macau Institute of CNS Regeneration, Jinan University, Guangzhou, 510632, China.
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11
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Alamri SH, Haque S, Alghamdi BS, Tayeb HO, Azhari S, Farsi RM, Elmokadem A, Alamri TA, Harakeh S, Prakash A, Kumar V. Comprehensive mapping of mutations in TDP-43 and α-Synuclein that affect stability and binding. J Biomol Struct Dyn 2023:1-13. [PMID: 38126188 DOI: 10.1080/07391102.2023.2293258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Accepted: 11/11/2023] [Indexed: 12/23/2023]
Abstract
Abnormal aggregation and amyloid inclusions of TAR DNA-binding protein 43 (TDP-43) and α-Synuclein (α-Syn) are frequently co-observed in amyotrophic lateral sclerosis, Parkinson's disease, and Alzheimer's disease. Several reports showed TDP-43 C-terminal domain (CTD) and α-Syn interact with each other and the aggregates of these two proteins colocalized together in different cellular and animal models. Molecular dynamics simulation was conducted to elucidate the stability of the TDP-43 and Syn complex structure. The interfacial mutations in protein complexes changes the stability and binding affinity of the protein that may cause diseases. Here, we have utilized the computational saturation mutagenesis approach including structure-based stability and binding energy calculations to compute the systemic effects of missense mutations of TDP-43 CTD and α-Syn on protein stability and binding affinity. Most of the interfacial mutations of CTD and α-Syn were found to destabilize the protein and reduced the protein binding affinity. The results thus shed light on the functional consequences of missense mutations observed in TDP-43 associated proteinopathies and may provide the mechanisms of co-morbidities involving these two proteins.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Sultan H Alamri
- Department of Family Medicine, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Shafiul Haque
- Research and Scientific Studies Unit, College of Nursing and Allied Health Sciences, Jazan University, Jazan, Saudi Arabia
- Gilbert and Rose-Marie Chagoury School of Medicine, Lebanese American University, Beirut, Lebanon
- Centre of Medical and Bio-Allied Health Sciences Research, Ajman University, Ajman, United Arab Emirates
| | - Badra S Alghamdi
- Department of Physiology, Neuroscience Unit, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia
- Pre-Clinical Research Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Haythum O Tayeb
- The Mind and Brain Studies Initiative, Neuroscience Research Unit, Department of Neurology, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Shereen Azhari
- Department of Biological Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Reem M Farsi
- Department of Biological Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Abear Elmokadem
- Department of Hematology/Pediatric Oncology, King Abdulaziz University Hospital, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Turki A Alamri
- Family and Community Medicine Department, Faculty of Medicine in Rabigh, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Steve Harakeh
- King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Jeddah, Saudi Arabia
- Yousef Abdul Latif Jameel Scientific Chair of Prophetic Medicine Application, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Amresh Prakash
- Amity Institute of Integrative Sciences and Health (AIISH), Amity University Haryana, Gurgaon, India
| | - Vijay Kumar
- Amity Institute of Neuropsychology & Neurosciences, Amity University, Noida, India
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12
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Babazadeh A, Rayner SL, Lee A, Chung RS. TDP-43 as a therapeutic target in neurodegenerative diseases: Focusing on motor neuron disease and frontotemporal dementia. Ageing Res Rev 2023; 92:102085. [PMID: 37813308 DOI: 10.1016/j.arr.2023.102085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Revised: 10/04/2023] [Accepted: 10/06/2023] [Indexed: 10/11/2023]
Abstract
A common feature of adult-onset neurodegenerative diseases is the presence of characteristic pathological accumulations of specific proteins. These pathological protein depositions can vary in their protein composition, cell-type distribution, and intracellular (or extracellular) location. For example, abnormal cytoplasmic protein deposits which consist of the TDP-43 protein are found within motor neurons in patients with amyotrophic lateral sclerosis (ALS, a common form of motor neuron disease) and frontotemporal dementia (FTD). The presence of these insoluble intracellular TDP-43 inclusions suggests that restoring TDP-43 homeostasis represents a potential therapeutical strategy, which has been demonstrated in alleviating neurodegenerative symptoms in cell and animal models of ALS/FTD. We have reviewed the mechanisms that lead to disrupted TDP-43 homeostasis and discussed how small molecule-based therapies could be applied in modulating these mechanisms. This review covers recent advancements and challenges in small molecule-based therapies that could be used to clear pathological forms of TDP-43 through various protein homeostasis mechanisms and advance the way towards finding effective therapeutical drug discoveries for neurodegenerative diseases characterized by TDP-43 proteinopathies, especially ALS and FTD. We also consider the wider insight of these therapeutic strategies for other neurodegenerative diseases.
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Affiliation(s)
- Afshin Babazadeh
- Centre for Motor Neuron Disease Research, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW 2109, Australia.
| | - Stephanie L Rayner
- Centre for Motor Neuron Disease Research, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW 2109, Australia.
| | - Albert Lee
- Centre for Motor Neuron Disease Research, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW 2109, Australia.
| | - Roger S Chung
- Centre for Motor Neuron Disease Research, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW 2109, Australia.
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13
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Wang Z, Zhang C, Fan C, Liu Y. Post-translational modifications in stress granule and their implications in neurodegenerative diseases. BIOCHIMICA ET BIOPHYSICA ACTA. GENE REGULATORY MECHANISMS 2023; 1866:194989. [PMID: 37751804 DOI: 10.1016/j.bbagrm.2023.194989] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Revised: 08/21/2023] [Accepted: 09/21/2023] [Indexed: 09/28/2023]
Abstract
Stress granules (SGs) arise as formations of mRNAs and proteins in response to translation initiation inhibition during stress. These dynamic compartments adopt a fluidic nature through liquid-liquid phase separation (LLPS), exhibiting a composition subject to constant change within cellular contexts. Research has unveiled an array of post-translational modifications (PTMs) occurring on SG proteins, intricately orchestrating SG dynamics. In the realm of neurodegenerative diseases, pathological mutant proteins congregate into insoluble aggregates alongside numerous SG proteins, manifesting resilience against disassembly. Specific PTMs conspicuously label these aggregates, designating them for subsequent degradation. The strategic manipulation of aberrant SGs via PTMs emerges as a promising avenue for therapeutic intervention. This review discerns recent strides in comprehending the impact of PTMs on LLPS behavior and the assembly/disassembly kinetics of SGs. By delving into the roles of PTMs in governing SG dynamics, we augment our cognizance of the molecular underpinnings of neurodegeneration. Furthermore, we offer invaluable insights into potential targets for therapeutic intervention in neurodegenerative afflictions, encompassing conditions like amyotrophic lateral sclerosis and frontotemporal dementia.
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Affiliation(s)
- Zhangshun Wang
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Chen'ang Zhang
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Chengyu Fan
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Yanfen Liu
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China.
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14
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Stella R, Bonadio RS, Cagnin S, Andreotti R, Massimino ML, Bertoli A, Peggion C. Secreted Metabolome of ALS-Related hSOD1(G93A) Primary Cultures of Myocytes and Implications for Myogenesis. Cells 2023; 12:2751. [PMID: 38067180 PMCID: PMC10706027 DOI: 10.3390/cells12232751] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 11/23/2023] [Accepted: 11/27/2023] [Indexed: 12/18/2023] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a motor neuron (MN) disease associated with progressive muscle atrophy, paralysis, and eventually death. Growing evidence demonstrates that the pathological process leading to ALS is the result of multiple altered mechanisms occurring not only in MNs but also in other cell types inside and outside the central nervous system. In this context, the involvement of skeletal muscle has been the subject of a few studies on patients and ALS animal models. In this work, by using primary myocytes derived from the ALS transgenic hSOD1(G93A) mouse model, we observed that the myogenic capability of such cells was defective compared to cells derived from control mice expressing the nonpathogenic hSOD1(WT) isoform. The correct in vitro myogenesis of hSOD1(G93A) primary skeletal muscle cells was rescued by the addition of a conditioned medium from healthy hSOD1(WT) myocytes, suggesting the existence of an in trans activity of secreted factors. To define a dataset of molecules participating in such safeguard action, we conducted comparative metabolomic profiling of a culture medium collected from hSOD1(G93A) and hSOD1(WT) primary myocytes and report here an altered secretion of amino acids and lipid-based signaling molecules. These findings support the urgency of better understanding the role of the skeletal muscle secretome in the regulation of the myogenic program and mechanisms of ALS pathogenesis and progression.
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Affiliation(s)
- Roberto Stella
- Istituto Zooprofilattico Sperimentale delle Venezie, 35020 Legnaro, Italy
| | | | - Stefano Cagnin
- Department of Biology, University of Padova, 35131 Padova, Italy (S.C.)
- CIR-Myo Myology Center, University of Padova, 35131 Padova, Italy
| | - Roberta Andreotti
- Department of Biomedical Sciences, University of Padova, 35131 Padova, Italy (A.B.)
| | - Maria Lina Massimino
- Neuroscience Institute, Consiglio Nazionale delle Ricerche, 35131 Padova, Italy;
| | - Alessandro Bertoli
- Department of Biomedical Sciences, University of Padova, 35131 Padova, Italy (A.B.)
- Neuroscience Institute, Consiglio Nazionale delle Ricerche, 35131 Padova, Italy;
- Padova Neuroscience Center, University of Padova, 35131 Padova, Italy
| | - Caterina Peggion
- Department of Biology, University of Padova, 35131 Padova, Italy (S.C.)
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15
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Pisciottani A, Croci L, Lauria F, Marullo C, Savino E, Ambrosi A, Podini P, Marchioretto M, Casoni F, Cremona O, Taverna S, Quattrini A, Cioni JM, Viero G, Codazzi F, Consalez GG. Neuronal models of TDP-43 proteinopathy display reduced axonal translation, increased oxidative stress, and defective exocytosis. Front Cell Neurosci 2023; 17:1253543. [PMID: 38026702 PMCID: PMC10679756 DOI: 10.3389/fncel.2023.1253543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Accepted: 10/13/2023] [Indexed: 12/01/2023] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a progressive, lethal neurodegenerative disease mostly affecting people around 50-60 years of age. TDP-43, an RNA-binding protein involved in pre-mRNA splicing and controlling mRNA stability and translation, forms neuronal cytoplasmic inclusions in an overwhelming majority of ALS patients, a phenomenon referred to as TDP-43 proteinopathy. These cytoplasmic aggregates disrupt mRNA transport and localization. The axon, like dendrites, is a site of mRNA translation, permitting the local synthesis of selected proteins. This is especially relevant in upper and lower motor neurons, whose axon spans long distances, likely accentuating their susceptibility to ALS-related noxae. In this work we have generated and characterized two cellular models, consisting of virtually pure populations of primary mouse cortical neurons expressing a human TDP-43 fusion protein, wt or carrying an ALS mutation. Both forms facilitate cytoplasmic aggregate formation, unlike the corresponding native proteins, giving rise to bona fide primary culture models of TDP-43 proteinopathy. Neurons expressing TDP-43 fusion proteins exhibit a global impairment in axonal protein synthesis, an increase in oxidative stress, and defects in presynaptic function and electrical activity. These changes correlate with deregulation of axonal levels of polysome-engaged mRNAs playing relevant roles in the same processes. Our data support the emerging notion that deregulation of mRNA metabolism and of axonal mRNA transport may trigger the dying-back neuropathy that initiates motor neuron degeneration in ALS.
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Affiliation(s)
- Alessandra Pisciottani
- Faculty of Medicine and Surgery, Università Vita-Salute San Raffaele, Milan, Italy
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Laura Croci
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Fabio Lauria
- Institute of Biophysics, CNR Unit at Trento, Povo, Italy
| | - Chiara Marullo
- Faculty of Medicine and Surgery, Università Vita-Salute San Raffaele, Milan, Italy
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Elisa Savino
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Alessandro Ambrosi
- Faculty of Medicine and Surgery, Università Vita-Salute San Raffaele, Milan, Italy
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Paola Podini
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | | | - Filippo Casoni
- Faculty of Medicine and Surgery, Università Vita-Salute San Raffaele, Milan, Italy
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Ottavio Cremona
- Faculty of Medicine and Surgery, Università Vita-Salute San Raffaele, Milan, Italy
| | - Stefano Taverna
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Angelo Quattrini
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Jean-Michel Cioni
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | | | - Franca Codazzi
- Faculty of Medicine and Surgery, Università Vita-Salute San Raffaele, Milan, Italy
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - G. Giacomo Consalez
- Faculty of Medicine and Surgery, Università Vita-Salute San Raffaele, Milan, Italy
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Milan, Italy
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16
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Lombardi M, Corrado L, Piola B, Comi C, Cantello R, D’Alfonso S, Mazzini L, De Marchi F. Variability in Clinical Phenotype in TARDBP Mutations: Amyotrophic Lateral Sclerosis Case Description and Literature Review. Genes (Basel) 2023; 14:2039. [PMID: 38002982 PMCID: PMC10671725 DOI: 10.3390/genes14112039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Revised: 10/30/2023] [Accepted: 10/31/2023] [Indexed: 11/26/2023] Open
Abstract
Mutations in the 43 kDa transactive-response (TAR)-DNA-binding protein (TARDBP) are associated with 2-5% of familial Amyotrophic Lateral Sclerosis (ALS) cases. TAR DNA-Binding Protein 43 (TDP-43) is an RNA/DNA-binding protein involved in several cellular mechanisms (e.g., transcription, pre-mRNA processing, and splicing). Many ALS-linked TARDBP mutations have been described in the literature, but few phenotypic data on monogenic TARDBP-mutated ALS are available. In this paper, (1) we describe the clinical features of ALS patients carrying mutations in the TARDBP gene evaluated at the Tertiary ALS Center at Maggiore della Carità University Hospital, Novara, Italy, from 2010 to 2020 and (2) present the results of our review of the literature on this topic, analyzing data obtained for 267 patients and highlighting their main clinical and demographic features.
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Affiliation(s)
- Michele Lombardi
- ALS Center, Neurology Unit, Department of Translational Medicine, University of Piemonte Orientale, 28100 Novara, Italy; (M.L.); (R.C.); (L.M.)
| | - Lucia Corrado
- Department of Health Sciences, University of Piemonte Orientale, 28100 Novara, Italy; (L.C.); (B.P.); (S.D.)
| | - Beatrice Piola
- Department of Health Sciences, University of Piemonte Orientale, 28100 Novara, Italy; (L.C.); (B.P.); (S.D.)
| | - Cristoforo Comi
- Neurology Unit, S. Andrea Hospital, Department of Translational Medicine, University of Piemonte Orientale, 13100 Vercelli, Italy;
| | - Roberto Cantello
- ALS Center, Neurology Unit, Department of Translational Medicine, University of Piemonte Orientale, 28100 Novara, Italy; (M.L.); (R.C.); (L.M.)
| | - Sandra D’Alfonso
- Department of Health Sciences, University of Piemonte Orientale, 28100 Novara, Italy; (L.C.); (B.P.); (S.D.)
| | - Letizia Mazzini
- ALS Center, Neurology Unit, Department of Translational Medicine, University of Piemonte Orientale, 28100 Novara, Italy; (M.L.); (R.C.); (L.M.)
| | - Fabiola De Marchi
- ALS Center, Neurology Unit, Department of Translational Medicine, University of Piemonte Orientale, 28100 Novara, Italy; (M.L.); (R.C.); (L.M.)
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17
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Helmold BR, Pauss KE, Ozdinler PH. TDP-43 protein interactome informs about perturbed canonical pathways and may help develop personalized medicine approaches for patients with TDP-43 pathology. Drug Discov Today 2023; 28:103769. [PMID: 37714405 PMCID: PMC10872580 DOI: 10.1016/j.drudis.2023.103769] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Revised: 08/22/2023] [Accepted: 09/08/2023] [Indexed: 09/17/2023]
Abstract
Transactive response DNA binding protein of 43 kDa (TDP-43) pathology is a common proteinopathy observed among a broad spectrum of patients with neurodegenerative disease, regardless of the mutation. This suggests that protein-protein interactions of TDP-43 with other proteins may in part be responsible for the pathology. To gain better insights, we investigated TDP-43-binding proteins in each domain and correlated these interactions with canonical pathways. These investigations revealed key cellular events that are involved and are important at each domain and suggested previously identified compounds to modulate key aspects of these canonical pathways. Our approach proposes that personalized medicine approaches, which focus on perturbed cellular mechanisms would be feasible in the near future.
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Affiliation(s)
- Benjamin R Helmold
- Department of Neurology, Feinberg School of Medicine, Northwestern University, 303 E. Chicago Ave, Chicago, IL, 60611, USA
| | - Kate E Pauss
- Department of Neurology, Feinberg School of Medicine, Northwestern University, 303 E. Chicago Ave, Chicago, IL, 60611, USA
| | - P Hande Ozdinler
- Department of Neurology, Feinberg School of Medicine, Northwestern University, 303 E. Chicago Ave, Chicago, IL, 60611, USA; Center for Molecular Innovation and Drug Discovery, Center for Developmental Therapeutics, Chemistry of Life Processes Institute, Northwestern University, Evanston, IL 60611, USA; Mesulam Center for Cognitive Neurology and Alzheimer's Disease, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA; Feinberg School of Medicine, Les Turner ALS Center at Northwestern University, Chicago, IL 60611, USA.
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18
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Genin EC, Abou-Ali M, Paquis-Flucklinger V. Mitochondria, a Key Target in Amyotrophic Lateral Sclerosis Pathogenesis. Genes (Basel) 2023; 14:1981. [PMID: 38002924 PMCID: PMC10671245 DOI: 10.3390/genes14111981] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 10/19/2023] [Accepted: 10/21/2023] [Indexed: 11/26/2023] Open
Abstract
Mitochondrial dysfunction occurs in numerous neurodegenerative diseases, particularly amyotrophic lateral sclerosis (ALS), where it contributes to motor neuron (MN) death. Of all the factors involved in ALS, mitochondria have been considered as a major player, as secondary mitochondrial dysfunction has been found in various models and patients. Abnormal mitochondrial morphology, defects in mitochondrial dynamics, altered activities of respiratory chain enzymes and increased production of reactive oxygen species have been described. Moreover, the identification of CHCHD10 variants in ALS patients was the first genetic evidence that a mitochondrial defect may be a primary cause of MN damage and directly links mitochondrial dysfunction to the pathogenesis of ALS. In this review, we focus on the role of mitochondria in ALS and highlight the pathogenic variants of ALS genes associated with impaired mitochondrial functions. The multiple pathways demonstrated in ALS pathogenesis suggest that all converge to a common endpoint leading to MN loss. This may explain the disappointing results obtained with treatments targeting a single pathological process. Fighting against mitochondrial dysfunction appears to be a promising avenue for developing combined therapies in the future.
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Affiliation(s)
- Emmanuelle C. Genin
- Institute for Research on Cancer and Aging, Nice (IRCAN), Université Côte d’Azur, Inserm U1081, CNRS UMR7284, Centre Hospitalier Universitaire (CHU) de Nice, 06200 Nice, France; (M.A.-A.); (V.P.-F.)
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19
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Gimenez J, Spalloni A, Cappelli S, Ciaiola F, Orlando V, Buratti E, Longone P. TDP-43 Epigenetic Facets and Their Neurodegenerative Implications. Int J Mol Sci 2023; 24:13807. [PMID: 37762112 PMCID: PMC10530927 DOI: 10.3390/ijms241813807] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Revised: 07/31/2023] [Accepted: 08/09/2023] [Indexed: 09/29/2023] Open
Abstract
Since its initial involvement in numerous neurodegenerative pathologies in 2006, either as a principal actor or as a cofactor, new pathologies implicating transactive response (TAR) DNA-binding protein 43 (TDP-43) are regularly emerging also beyond the neuronal system. This reflects the fact that TDP-43 functions are particularly complex and broad in a great variety of human cells. In neurodegenerative diseases, this protein is often pathologically delocalized to the cytoplasm, where it irreversibly aggregates and is subjected to various post-translational modifications such as phosphorylation, polyubiquitination, and cleavage. Until a few years ago, the research emphasis has been focused particularly on the impacts of this aggregation and/or on its widely described role in complex RNA splicing, whether related to loss- or gain-of-function mechanisms. Interestingly, recent studies have strengthened the knowledge of TDP-43 activity at the chromatin level and its implication in the regulation of DNA transcription and stability. These discoveries have highlighted new features regarding its own transcriptional regulation and suggested additional mechanistic and disease models for the effects of TPD-43. In this review, we aim to give a comprehensive view of the potential epigenetic (de)regulations driven by (and driving) this multitask DNA/RNA-binding protein.
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Affiliation(s)
- Juliette Gimenez
- Molecular Neurobiology Laboratory, Experimental Neuroscience, IRCCS Fondazione Santa Lucia (FSL), 00143 Rome, Italy; (A.S.); (P.L.)
| | - Alida Spalloni
- Molecular Neurobiology Laboratory, Experimental Neuroscience, IRCCS Fondazione Santa Lucia (FSL), 00143 Rome, Italy; (A.S.); (P.L.)
| | - Sara Cappelli
- Molecular Pathology Laboratory, International Centre for Genetic Engineering and Biotechnology (ICGEB), 34149 Trieste, Italy; (S.C.); (E.B.)
| | - Francesca Ciaiola
- Molecular Neurobiology Laboratory, Experimental Neuroscience, IRCCS Fondazione Santa Lucia (FSL), 00143 Rome, Italy; (A.S.); (P.L.)
- Department of Systems Medicine, University of Roma Tor Vergata, 00133 Rome, Italy
| | - Valerio Orlando
- KAUST Environmental Epigenetics Program, Biological Environmental Sciences and Engineering Division BESE, King Abdullah University of Science and Technology (KAUST), Thuwal 23955, Saudi Arabia;
| | - Emanuele Buratti
- Molecular Pathology Laboratory, International Centre for Genetic Engineering and Biotechnology (ICGEB), 34149 Trieste, Italy; (S.C.); (E.B.)
| | - Patrizia Longone
- Molecular Neurobiology Laboratory, Experimental Neuroscience, IRCCS Fondazione Santa Lucia (FSL), 00143 Rome, Italy; (A.S.); (P.L.)
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20
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Cao MC, Ryan B, Wu J, Curtis MA, Faull RLM, Dragunow M, Scotter EL. A panel of TDP-43-regulated splicing events verifies loss of TDP-43 function in amyotrophic lateral sclerosis brain tissue. Neurobiol Dis 2023; 185:106245. [PMID: 37527763 DOI: 10.1016/j.nbd.2023.106245] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Revised: 07/13/2023] [Accepted: 07/28/2023] [Indexed: 08/03/2023] Open
Abstract
TDP-43 dysfunction is a molecular hallmark of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). A major hypothesis of TDP-43 dysfunction in disease is the loss of normal nuclear function, resulting in impaired RNA regulation and the emergence of cryptic exons. Cryptic exons and differential exon usage are emerging as promising markers of lost TDP-43 function in addition to revealing biological pathways involved in neurodegeneration in ALS/FTD. In this brief report, we identified markers of TDP-43 loss of function by depleting TARDBP from post-mortem human brain pericytes, a manipulable in vitro primary human brain cell model, and identifying differential exon usage events with bulk RNA-sequencing analysis. We present these data in an interactive database (https://www.scotterlab.auckland.ac.nz/research-themes/tdp43-lof-db-v2/) together with seven other TDP-43-depletion datasets we meta-analysed previously, for user analysis of differential expression and splicing signatures. Differential exon usage events that were validated by qPCR were then compiled into a 'differential exon usage panel' with other well-established TDP-43 loss-of-function exon markers. This differential exon usage panel was investigated in ALS and control motor cortex tissue to verify whether, and to what extent, TDP-43 loss of function occurs in ALS. We find that profiles of TDP-43-regulated cryptic exons, changed exon usage and changed 3' UTR usage discriminate ALS brain tissue from controls, verifying that TDP-43 loss of function occurs in ALS. We propose that TDP-43-regulated splicing events that occur in brain tissue will have promise as predictors of disease.
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Affiliation(s)
- Maize C Cao
- Department of Pharmacology, University of Auckland, New Zealand; Centre for Brain Research, University of Auckland, New Zealand.
| | - Brigid Ryan
- Department of Anatomy and Medical Imaging, University of Auckland, New Zealand; Centre for Brain Research, University of Auckland, New Zealand.
| | - Jane Wu
- Department of Anatomy and Medical Imaging, University of Auckland, New Zealand; Centre for Brain Research, University of Auckland, New Zealand.
| | - Maurice A Curtis
- Department of Anatomy and Medical Imaging, University of Auckland, New Zealand; Centre for Brain Research, University of Auckland, New Zealand.
| | - Richard L M Faull
- Department of Anatomy and Medical Imaging, University of Auckland, New Zealand; Centre for Brain Research, University of Auckland, New Zealand.
| | - Mike Dragunow
- Department of Pharmacology, University of Auckland, New Zealand; Centre for Brain Research, University of Auckland, New Zealand.
| | - Emma L Scotter
- School of Biological Sciences, University of Auckland, New Zealand; Centre for Brain Research, University of Auckland, New Zealand.
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21
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Naskar A, Nayak A, Salaikumaran MR, Vishal SS, Gopal PP. Phase separation and pathologic transitions of RNP condensates in neurons: implications for amyotrophic lateral sclerosis, frontotemporal dementia and other neurodegenerative disorders. Front Mol Neurosci 2023; 16:1242925. [PMID: 37720552 PMCID: PMC10502346 DOI: 10.3389/fnmol.2023.1242925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Accepted: 08/21/2023] [Indexed: 09/19/2023] Open
Abstract
Liquid-liquid phase separation results in the formation of dynamic biomolecular condensates, also known as membrane-less organelles, that allow for the assembly of functional compartments and higher order structures within cells. Multivalent, reversible interactions between RNA-binding proteins (RBPs), including FUS, TDP-43, and hnRNPA1, and/or RNA (e.g., RBP-RBP, RBP-RNA, RNA-RNA), result in the formation of ribonucleoprotein (RNP) condensates, which are critical for RNA processing, mRNA transport, stability, stress granule assembly, and translation. Stress granules, neuronal transport granules, and processing bodies are examples of cytoplasmic RNP condensates, while the nucleolus and Cajal bodies are representative nuclear RNP condensates. In neurons, RNP condensates promote long-range mRNA transport and local translation in the dendrites and axon, and are essential for spatiotemporal regulation of gene expression, axonal integrity and synaptic function. Mutations of RBPs and/or pathologic mislocalization and aggregation of RBPs are hallmarks of several neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS), frontotemporal dementia (FTD), and Alzheimer's disease. ALS/FTD-linked mutations of RBPs alter the strength and reversibility of multivalent interactions with other RBPs and RNAs, resulting in aberrant phase transitions. These aberrant RNP condensates have detrimental functional consequences on mRNA stability, localization, and translation, and ultimately lead to compromised axonal integrity and synaptic function in disease. Pathogenic protein aggregation is dependent on various factors, and aberrant dynamically arrested RNP condensates may serve as an initial nucleation step for pathologic aggregate formation. Recent studies have focused on identifying mechanisms by which neurons resolve phase transitioned condensates to prevent the formation of pathogenic inclusions/aggregates. The present review focuses on the phase separation of neurodegenerative disease-linked RBPs, physiological functions of RNP condensates, and the pathologic role of aberrant phase transitions in neurodegenerative disease, particularly ALS/FTD. We also examine cellular mechanisms that contribute to the resolution of aberrant condensates in neurons, and potential therapeutic approaches to resolve aberrantly phase transitioned condensates at a molecular level.
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Affiliation(s)
- Aditi Naskar
- Department of Pathology, Yale School of Medicine, New Haven, CT, United States
| | - Asima Nayak
- Department of Pathology, Yale School of Medicine, New Haven, CT, United States
| | | | - Sonali S. Vishal
- Department of Pathology, Yale School of Medicine, New Haven, CT, United States
| | - Pallavi P. Gopal
- Department of Pathology, Yale School of Medicine, New Haven, CT, United States
- Program in Cellular Neuroscience, Neurodegeneration, and Repair, Yale School of Medicine, New Haven, CT, United States
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22
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Wang S, Sun S. Translation dysregulation in neurodegenerative diseases: a focus on ALS. Mol Neurodegener 2023; 18:58. [PMID: 37626421 PMCID: PMC10464328 DOI: 10.1186/s13024-023-00642-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Accepted: 07/21/2023] [Indexed: 08/27/2023] Open
Abstract
RNA translation is tightly controlled in eukaryotic cells to regulate gene expression and maintain proteome homeostasis. RNA binding proteins, translation factors, and cell signaling pathways all modulate the translation process. Defective translation is involved in multiple neurological diseases including amyotrophic lateral sclerosis (ALS). ALS is a progressive neurodegenerative disorder and poses a major public health challenge worldwide. Over the past few years, tremendous advances have been made in the understanding of the genetics and pathogenesis of ALS. Dysfunction of RNA metabolisms, including RNA translation, has been closely associated with ALS. Here, we first introduce the general mechanisms of translational regulation under physiological and stress conditions and review well-known examples of translation defects in neurodegenerative diseases. We then focus on ALS-linked genes and discuss the recent progress on how translation is affected by various mutant genes and the repeat expansion-mediated non-canonical translation in ALS.
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Affiliation(s)
- Shaopeng Wang
- Department of Physiology and Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Shuying Sun
- Department of Physiology and Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
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23
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Zhang X, Das T, Kalab P, Hayes LR. Multivalent GU-rich oligonucleotides sequester TDP-43 in the nucleus by inducing high molecular weight RNP complexes. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.01.551528. [PMID: 37577513 PMCID: PMC10418175 DOI: 10.1101/2023.08.01.551528] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/15/2023]
Abstract
The loss of nuclear TDP-43 localization and its accumulation in cytoplasmic aggregates are hallmarks of neurodegeneration and major therapeutic targets. We recently demonstrated that TDP-43 binding to endogenous nuclear GU-rich RNAs sequesters TDP-43 in the nucleus and restricts its passive nuclear export. Here, we tested the feasibility of synthetic RNA oligonucleotide-mediated augmentation of TDP-43 nuclear localization. Using biochemical assays, we compared the ability of GU-rich oligonucleotides to engage in multivalent, RRM-dependent binding with TDP-43 and identified (GU)16 as a strong multivalent binder. When transfected into cells, unlike monovalent oligonucleotides that displaced TDP-43 from the nucleus, (GU)16 preserved steady-state TDP-43 nuclear localization and prevented transcriptional blockade-induced TDP-43 mislocalization. RNA pulldowns from (GU)16-transfected cells confirmed that (GU)16 induced high molecular weight RNP complexes, incorporating TDP-43 and possibly other GU-binding proteins. Transfected (GU)16 caused partial failure of TDP-43 cryptic exon repression, likely because the high-affinity oligonucleotides diverted TDP-43 from endogenous RNAs. Thus, while GU-rich oligonucleotides can attenuate TDP-43 mislocalization, optimization is needed to avoid TDP-43 loss of function.
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24
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Acosta-Galeana I, Hernández-Martínez R, Reyes-Cruz T, Chiquete E, Aceves-Buendia JDJ. RNA-binding proteins as a common ground for neurodegeneration and inflammation in amyotrophic lateral sclerosis and multiple sclerosis. Front Mol Neurosci 2023; 16:1193636. [PMID: 37475885 PMCID: PMC10355071 DOI: 10.3389/fnmol.2023.1193636] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2023] [Accepted: 06/14/2023] [Indexed: 07/22/2023] Open
Abstract
The neurodegenerative and inflammatory illnesses of amyotrophic lateral sclerosis and multiple sclerosis were once thought to be completely distinct entities that did not share any remarkable features, but new research is beginning to reveal more information about their similarities and differences. Here, we review some of the pathophysiological features of both diseases and their experimental models: RNA-binding proteins, energy balance, protein transportation, and protein degradation at the molecular level. We make a thorough analysis on TDP-43 and hnRNP A1 dysfunction, as a possible common ground in both pathologies, establishing a potential link between neurodegeneration and pathological immunity. Furthermore, we highlight the putative variations that diverge from a common ground in an atemporal course that proposes three phases for all relevant molecular events.
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Affiliation(s)
| | | | - Tania Reyes-Cruz
- Laboratorio de Biología Molecular, División de Ciencias Biológicas y de la Salud, Universidad Autónoma Metropolitana, Mexico City, Mexico
| | - Erwin Chiquete
- Departamento de Neurología y Psiquiatría, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico City, Mexico
| | - Jose de Jesus Aceves-Buendia
- Departamento de Neurología y Psiquiatría, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico City, Mexico
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25
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Ionescu A, Altman T, Perlson E. Looking for answers far away from the soma-the (un)known axonal functions of TDP-43, and their contribution to early NMJ disruption in ALS. Mol Neurodegener 2023; 18:35. [PMID: 37259156 DOI: 10.1186/s13024-023-00623-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Accepted: 05/01/2023] [Indexed: 06/02/2023] Open
Abstract
Axon degeneration and Neuromuscular Junction (NMJ) disruption are key pathologies in the fatal neurodegenerative disease Amyotrophic Lateral Sclerosis (ALS). Despite accumulating evidence that axons and NMJs are impacted at a very early stage of the disease, current knowledge about the mechanisms leading to their degeneration remains elusive. Cytoplasmic mislocalization and accumulation of the protein TDP-43 are considered key pathological hallmarks of ALS, as they occur in ~ 97% of ALS patients, both sporadic and familial. Recent studies have identified pathological accumulation of TDP-43 in intramuscular nerves of muscle biopsies collected from pre-diagnosed, early symptomatic ALS patients. These findings suggest a gain of function for TDP-43 in axons, which might facilitate early NMJ disruption. In this review, we dissect the process leading to axonal TDP-43 accumulation and phosphorylation, discuss the known and hypothesized roles TDP-43 plays in healthy axons, and review possible mechanisms that connect TDP-43 pathology to the axon and NMJ degeneration in ALS.
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Affiliation(s)
- Ariel Ionescu
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Room 605, Ramat Aviv, 69978, Tel Aviv, Israel
| | - Topaz Altman
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Room 605, Ramat Aviv, 69978, Tel Aviv, Israel
| | - Eran Perlson
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Room 605, Ramat Aviv, 69978, Tel Aviv, Israel.
- Sagol School of Neuroscience, Tel-Aviv University, Tel-Aviv, Israel.
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26
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Kumar ST, Nazarov S, Porta S, Maharjan N, Cendrowska U, Kabani M, Finamore F, Xu Y, Lee VMY, Lashuel HA. Seeding the aggregation of TDP-43 requires post-fibrillization proteolytic cleavage. Nat Neurosci 2023:10.1038/s41593-023-01341-4. [PMID: 37248338 DOI: 10.1038/s41593-023-01341-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Accepted: 04/18/2023] [Indexed: 05/31/2023]
Abstract
Despite the strong evidence linking the transactive response DNA-binding protein 43 (TDP-43) aggregation to the pathogenesis of frontotemporal lobar degeneration with TDP-43, amyotrophic lateral sclerosis and several neurodegenerative diseases, our knowledge of the sequence and structural determinants of its aggregation and neurotoxicity remains incomplete. Herein, we present a new method for producing recombinant full-length TDP-43 filaments that exhibit sequence and morphological features similar to those of brain-derived TDP-43 filaments. We show that TDP-43 filaments contain a β-sheet-rich helical amyloid core that is fully buried by the flanking structured domains of the protein. We demonstrate that the proteolytic cleavage of TDP-43 filaments and exposure of this amyloid core are necessary for propagating TDP-43 pathology and enhancing the seeding of brain-derived TDP-43 aggregates. Only TDP-43 filaments with exposed amyloid core efficiently seeded the aggregation of endogenous TDP-43 in cells. These findings suggest that inhibiting the enzymes mediating cleavage of TDP-43 aggregates represents a viable disease-modifying strategy to slow the progression of amyotrophic lateral sclerosis and other TDP-43 proteinopathies.
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Affiliation(s)
- Senthil T Kumar
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, Brain Mind Institute, EPFL, Lausanne, Switzerland
| | - Sergey Nazarov
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, Brain Mind Institute, EPFL, Lausanne, Switzerland
| | - Sílvia Porta
- Center for Neurodegenerative Disease Research (CNDR), Department of Pathology and Laboratory Medicine, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA, USA
| | - Niran Maharjan
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, Brain Mind Institute, EPFL, Lausanne, Switzerland
| | - Urszula Cendrowska
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, Brain Mind Institute, EPFL, Lausanne, Switzerland
| | - Malek Kabani
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, Brain Mind Institute, EPFL, Lausanne, Switzerland
| | - Francesco Finamore
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, Brain Mind Institute, EPFL, Lausanne, Switzerland
| | - Yan Xu
- Center for Neurodegenerative Disease Research (CNDR), Department of Pathology and Laboratory Medicine, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA, USA
| | - Virginia M-Y Lee
- Center for Neurodegenerative Disease Research (CNDR), Department of Pathology and Laboratory Medicine, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA, USA
| | - Hilal A Lashuel
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, Brain Mind Institute, EPFL, Lausanne, Switzerland.
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27
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Jung KH, Sun J, Hsiung CH, Lance Lian X, Liu Y, Zhang X. Nuclear bodies protect phase separated proteins from degradation in stressed proteome. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.19.537522. [PMID: 37131610 PMCID: PMC10153235 DOI: 10.1101/2023.04.19.537522] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
RNA-binding proteins (RBPs) containing intrinsically disordered domains undergo liquid-liquid phase separation to form nuclear bodies under stress conditions. This process is also connected to the misfolding and aggregation of RBPs, which are associated with a series of neurodegenerative diseases. However, it remains elusive how folding states of RBPs changes upon the formation and maturation of nuclear bodies. Here, we describe SNAP-tag based imaging methods to visualize the folding states of RBPs in live cells via time-resolved quantitative microscopic analyses of their micropolarity and microviscosity. Using these imaging methods in conjunction with immunofluorescence imaging, we demonstrate that RBPs, represented by TDP-43, initially enters the PML nuclear bodies in its native state upon transient proteostasis stress, albeit it begins to misfolded during prolonged stress. Furthermore, we show that heat shock protein 70 co-enters the PML nuclear bodies to prevent the degradation of TDP-43 from the proteotoxic stress, thus revealing a previously unappreciated protective role of the PML nuclear bodies in the prevention of stress-induced degradation of TDP-43. In summary, our imaging methods described in the manuscript, for the first time, reveal the folding states of RBPs, which were previously challenging to study with conventional methods in nuclear bodies of live cells. This study uncovers the mechanistic correlations between the folding states of a protein and functions of nuclear bodies, in particular PML bodies. We envision that the imaging methods can be generally applied to elucidating the structural aspects of other proteins that exhibit granular structures under biological stimulus.
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Affiliation(s)
- Kwan Ho Jung
- Department of Chemistry, Department of Biochemistry and Molecular Biology, The Huck Institute of Life Sciences, The Pennsylvania State University, University Park, Pennsylvania, 16802, United States
| | - Jiarui Sun
- Department of Chemistry, Department of Biochemistry and Molecular Biology, The Huck Institute of Life Sciences, The Pennsylvania State University, University Park, Pennsylvania, 16802, United States
| | - Chia-Heng Hsiung
- Department of Chemistry, Department of Biochemistry and Molecular Biology, The Huck Institute of Life Sciences, The Pennsylvania State University, University Park, Pennsylvania, 16802, United States
- Present address: Department of Chemistry, School of Science and Research Center for Industries of the Future, Westlake University, 600 Dunyu Road, Hangzhou 310030, Zhejiang Province, China; Westlake Laboratory of Life Sciences and Biomedicine; 18 Shilongshan Road, Hangzhou 310024, Zhejiang Province, China
- Department of Biomedical Engineering, The Huck Institute of Life Sciences, Department of Biology, The Pennsylvania State University, University Park, Pennsylvania, 16802, United States
| | - Xiaojun Lance Lian
- Department of Biomedical Engineering, The Huck Institute of Life Sciences, Department of Biology, The Pennsylvania State University, University Park, Pennsylvania, 16802, United States
| | - Yu Liu
- Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning, 116023, China
| | - Xin Zhang
- Department of Chemistry, Department of Biochemistry and Molecular Biology, The Huck Institute of Life Sciences, The Pennsylvania State University, University Park, Pennsylvania, 16802, United States
- Present address: Department of Chemistry, School of Science and Research Center for Industries of the Future, Westlake University, 600 Dunyu Road, Hangzhou 310030, Zhejiang Province, China; Westlake Laboratory of Life Sciences and Biomedicine; 18 Shilongshan Road, Hangzhou 310024, Zhejiang Province, China
- Department of Biomedical Engineering, The Huck Institute of Life Sciences, Department of Biology, The Pennsylvania State University, University Park, Pennsylvania, 16802, United States
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28
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Ishiguro A, Ishihama A. ALS-linked TDP-43 mutations interfere with the recruitment of RNA recognition motifs to G-quadruplex RNA. Sci Rep 2023; 13:5982. [PMID: 37046025 PMCID: PMC10097714 DOI: 10.1038/s41598-023-33172-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Accepted: 04/08/2023] [Indexed: 04/14/2023] Open
Abstract
TDP-43 is a major pathological protein in sporadic and familial amyotrophic lateral sclerosis (ALS) and mediates mRNA fate. TDP-43 dysfunction leads to causes progressive degeneration of motor neurons, the details of which remain elusive. Elucidation of the molecular mechanisms of RNA binding could enhance our understanding of this devastating disease. We observed the involvement of the glycine-rich (GR) region of TDP-43 in the initial recognition and binding of G-quadruplex (G4)-RNA in conjunction with its RNA recognition motifs (RRM). We performed a molecular dissection of these intramolecular RNA-binding modules in this study. We confirmed that the ALS-linked mutations in the GR region lead to alteration in the G4 structure. In contrast, amino acid substitutions in the GR region alter the protein structure but do not void the interaction with G4-RNA. Based on these observations, we concluded that the structural distortion of G4 caused by these mutations interferes with RRM recruitment and leads to TDP-43 dysfunction. This intramolecular organization between RRM and GR regions modulates the overall G4-binding properties.
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Affiliation(s)
- Akira Ishiguro
- Research Center for Micro-Nano Technology, Hosei University, Midori-cho 3-11-15, Koganei, Tokyo, 184-0003, Japan.
| | - Akira Ishihama
- Research Center for Micro-Nano Technology, Hosei University, Midori-cho 3-11-15, Koganei, Tokyo, 184-0003, Japan
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29
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Shenoy J, Lends A, Berbon M, Bilal M, El Mammeri N, Bertoni M, Saad A, Morvan E, Grélard A, Lecomte S, Theillet FX, Buell AK, Kauffmann B, Habenstein B, Loquet A. Structural polymorphism of the low-complexity C-terminal domain of TDP-43 amyloid aggregates revealed by solid-state NMR. Front Mol Biosci 2023; 10:1148302. [PMID: 37065450 PMCID: PMC10095165 DOI: 10.3389/fmolb.2023.1148302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Accepted: 03/17/2023] [Indexed: 03/31/2023] Open
Abstract
Aberrant aggregation of the transactive response DNA-binding protein (TDP-43) is associated with several lethal neurodegenerative diseases, including amyotrophic lateral sclerosis and frontotemporal dementia. Cytoplasmic neuronal inclusions of TDP-43 are enriched in various fragments of the low-complexity C-terminal domain and are associated with different neurotoxicity. Here we dissect the structural basis of TDP-43 polymorphism using magic-angle spinning solid-state NMR spectroscopy in combination with electron microscopy and Fourier-transform infrared spectroscopy. We demonstrate that various low-complexity C-terminal fragments, namely TDP-13 (TDP-43300–414), TDP-11 (TDP-43300–399), and TDP-10 (TDP-43314–414), adopt distinct polymorphic structures in their amyloid fibrillar state. Our work demonstrates that the removal of less than 10% of the low-complexity sequence at N- and C-termini generates amyloid fibrils with comparable macroscopic features but different local structural arrangement. It highlights that the assembly mechanism of TDP-43, in addition to the aggregation of the hydrophobic region, is also driven by complex interactions involving low-complexity aggregation-prone segments that are a potential source of structural polymorphism.
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Affiliation(s)
- Jayakrishna Shenoy
- University Bordeaux, CNRS, Bordeaux INP, CBMN, UMR 5248, IECB, Pessac, France
| | - Alons Lends
- University Bordeaux, CNRS, Bordeaux INP, CBMN, UMR 5248, IECB, Pessac, France
| | - Mélanie Berbon
- University Bordeaux, CNRS, Bordeaux INP, CBMN, UMR 5248, IECB, Pessac, France
| | - Muhammed Bilal
- University Bordeaux, CNRS, Bordeaux INP, CBMN, UMR 5248, IECB, Pessac, France
| | - Nadia El Mammeri
- University Bordeaux, CNRS, Bordeaux INP, CBMN, UMR 5248, IECB, Pessac, France
| | - Mathilde Bertoni
- University Bordeaux, CNRS, Bordeaux INP, CBMN, UMR 5248, IECB, Pessac, France
| | - Ahmad Saad
- University Bordeaux, CNRS, Bordeaux INP, CBMN, UMR 5248, IECB, Pessac, France
| | - Estelle Morvan
- University Bordeaux, CNRS, INSERM, IECB, UAR 3033, Pessac, France
| | - Axelle Grélard
- University Bordeaux, CNRS, Bordeaux INP, CBMN, UMR 5248, IECB, Pessac, France
| | - Sophie Lecomte
- University Bordeaux, CNRS, Bordeaux INP, CBMN, UMR 5248, IECB, Pessac, France
| | - François-Xavier Theillet
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, Gif-surYvette Cedex, France
| | - Alexander K. Buell
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Lyngby, Denmark
| | - Brice Kauffmann
- University Bordeaux, CNRS, INSERM, IECB, UAR 3033, Pessac, France
| | - Birgit Habenstein
- University Bordeaux, CNRS, Bordeaux INP, CBMN, UMR 5248, IECB, Pessac, France
- *Correspondence: Birgit Habenstein, ; Antoine Loquet,
| | - Antoine Loquet
- University Bordeaux, CNRS, Bordeaux INP, CBMN, UMR 5248, IECB, Pessac, France
- *Correspondence: Birgit Habenstein, ; Antoine Loquet,
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30
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Gautam M, Genç B, Helmold B, Ahrens A, Kuka J, Makrecka-Kuka M, Günay A, Koçak N, Aguilar-Wickings IR, Keefe D, Zheng G, Swaminathan S, Redmon M, Zariwala HA, Özdinler PH. SBT-272 improves TDP-43 pathology in ALS upper motor neurons by modulating mitochondrial integrity, motility, and function. Neurobiol Dis 2023; 178:106022. [PMID: 36716828 DOI: 10.1016/j.nbd.2023.106022] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 01/09/2023] [Accepted: 01/25/2023] [Indexed: 01/28/2023] Open
Abstract
Mitochondrial defects are one of the common underlying causes of neuronal vulnerability in neurodegenerative diseases, such as amyotrophic lateral sclerosis (ALS), and TDP-43 pathology is the most commonly observed proteinopathy. Disrupted inner mitochondrial membrane (IMM) reported in the upper motor neurons (UMNs) of ALS patients with TDP-43 pathology is recapitulated in the UMNs of well-characterized hTDP-43 mouse model of ALS. The construct validity, such as shared and common cellular pathology in mice and human, offers a unique opportunity to test treatment strategies that may translate to patients. SBT-272 is a well-tolerated brain-penetrant small molecule that stabilizes cardiolipin, a phospholipid found in IMM, thereby restoring mitochondrial structure and respiratory function. We investigated whether SBT-272 can improve IMM structure and health in UMNs diseased with TDP-43 pathology in our well-characterized UMN reporter line for ALS. We found that SBT-272 significantly improved mitochondrial structural integrity and restored mitochondrial motility and function. This led to improved health of diseased UMNs in vitro. In comparison to edaravone and AMX0035, SBT-272 appeared more effective in restoring health of diseased UMNs. Chronic treatment of SBT-272 for sixty days starting at an early symptomatic stage of the disease in vivo led to a significant reduction in astrogliosis, microgliosis, and TDP-43 pathology in the ALS motor cortex. Our results underscore the therapeutic potential of SBT-272, especially within the context of TDP-43 pathology and mitochondrial dysfunction.
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Affiliation(s)
- Mukesh Gautam
- Department of Neurology, Feinberg School of Medicine, Northwestern University, 303 E Chicago Ave, Chicago, IL 60611, USA
| | - Barış Genç
- Department of Neurology, Feinberg School of Medicine, Northwestern University, 303 E Chicago Ave, Chicago, IL 60611, USA
| | - Benjamin Helmold
- Department of Neurology, Feinberg School of Medicine, Northwestern University, 303 E Chicago Ave, Chicago, IL 60611, USA
| | - Angela Ahrens
- Department of Neurology, Feinberg School of Medicine, Northwestern University, 303 E Chicago Ave, Chicago, IL 60611, USA
| | - Janis Kuka
- Latvian Institute of Organic Synthesis (LIOS), Aizkraukles Street 21, LV-2006 Riga, Latvia
| | - Marina Makrecka-Kuka
- Latvian Institute of Organic Synthesis (LIOS), Aizkraukles Street 21, LV-2006 Riga, Latvia
| | - Aksu Günay
- Department of Neurology, Feinberg School of Medicine, Northwestern University, 303 E Chicago Ave, Chicago, IL 60611, USA
| | - Nuran Koçak
- Department of Neurology, Feinberg School of Medicine, Northwestern University, 303 E Chicago Ave, Chicago, IL 60611, USA
| | - Izaak R Aguilar-Wickings
- Department of Neurology, Feinberg School of Medicine, Northwestern University, 303 E Chicago Ave, Chicago, IL 60611, USA
| | - Dennis Keefe
- Stealth BioTherapeutics, 140 Kendrick St Building C, Needham, MA 02494, USA
| | - Guozhu Zheng
- Stealth BioTherapeutics, 140 Kendrick St Building C, Needham, MA 02494, USA
| | - Suchitra Swaminathan
- Division of Rheumatology, Department of Medicine, Feinberg School of Medicine, Northwestern University, 420 E Superior St, Chicago, IL 60611, USA.; Robert H. Lurie Comprehensive Cancer Research Center, Feinberg School of Medicine, Northwestern University, 675 N St Clair Fl 21 Ste 100, Chicago, IL 60611, USA
| | - Martin Redmon
- Stealth BioTherapeutics, 140 Kendrick St Building C, Needham, MA 02494, USA
| | - Hatim A Zariwala
- Stealth BioTherapeutics, 140 Kendrick St Building C, Needham, MA 02494, USA
| | - P Hande Özdinler
- Department of Neurology, Feinberg School of Medicine, Northwestern University, 303 E Chicago Ave, Chicago, IL 60611, USA; Robert H. Lurie Comprehensive Cancer Research Center, Feinberg School of Medicine, Northwestern University, 675 N St Clair Fl 21 Ste 100, Chicago, IL 60611, USA; Department of Molecular Biosciences, Chemistry of Life Processes Institute, Center for Molecular Innovation and Drug Discovery, Center for Developmental Therapeutics, Northwestern University, 2205 Tech Dr, Evanston, IL 60208, USA..
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31
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Tsoi PS, Quan MD, Ferreon JC, Ferreon ACM. Aggregation of Disordered Proteins Associated with Neurodegeneration. Int J Mol Sci 2023; 24:3380. [PMID: 36834792 PMCID: PMC9966039 DOI: 10.3390/ijms24043380] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2023] [Revised: 02/02/2023] [Accepted: 02/06/2023] [Indexed: 02/10/2023] Open
Abstract
Cellular deposition of protein aggregates, one of the hallmarks of neurodegeneration, disrupts cellular functions and leads to neuronal death. Mutations, posttranslational modifications, and truncations are common molecular underpinnings in the formation of aberrant protein conformations that seed aggregation. The major proteins involved in neurodegeneration include amyloid beta (Aβ) and tau in Alzheimer's disease, α-synuclein in Parkinson's disease, and TAR DNA-binding protein (TDP-43) in amyotrophic lateral sclerosis (ALS). These proteins are described as intrinsically disordered and possess enhanced ability to partition into biomolecular condensates. In this review, we discuss the role of protein misfolding and aggregation in neurodegenerative diseases, specifically highlighting implications of changes to the primary/secondary (mutations, posttranslational modifications, and truncations) and the quaternary/supramolecular (oligomerization and condensation) structural landscapes for the four aforementioned proteins. Understanding these aggregation mechanisms provides insights into neurodegenerative diseases and their common underlying molecular pathology.
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Affiliation(s)
| | | | - Josephine C. Ferreon
- Department of Pharmacology and Chemical Biology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Allan Chris M. Ferreon
- Department of Pharmacology and Chemical Biology, Baylor College of Medicine, Houston, TX 77030, USA
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Ni J, Ren Y, Su T, Zhou J, Fu C, Lu Y, Li D, Zhao J, Li Y, Zhang Y, Fang Y, Liu N, Geng Y, Chen Y. Loss of TDP-43 function underlies hippocampal and cortical synaptic deficits in TDP-43 proteinopathies. Mol Psychiatry 2023; 28:931-945. [PMID: 34697451 DOI: 10.1038/s41380-021-01346-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 09/30/2021] [Accepted: 10/04/2021] [Indexed: 12/13/2022]
Abstract
TDP-43 proteinopathy is linked to neurodegenerative diseases that feature synaptic loss in the cortex and hippocampus, although it remains unclear how TDP-43 regulates mature synapses. We report that, in adult mouse hippocampus, TDP-43 knockdown, but not overexpression, induces robust structural and functional damage to excitatory synapses, supporting a role for TDP-43 in maintaining mature synapses. Dendritic spine loss induced by TDP-43 knockdown is rescued by wild-type TDP-43, but not ALS/FTLD-associated mutants, suggesting a common TDP-43 functional deficiency in neurodegenerative diseases. Interestingly, M337V and A90V mutants also display dominant negative activities against WT TDP-43, partially explaining why M337V transgenic mice develop hippocampal degeneration similar to that in excitatory neuronal TDP-43 knockout mice, and why A90V mutation is associated with Alzheimer's disease. Further analyses reveal that a TDP-43 knockdown-induced reduction in GluN2A contributes to synaptic loss. Our results show that loss of TDP-43 function underlies hippocampal and cortical synaptic degeneration in TDP-43 proteinopathies.
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Affiliation(s)
- Jiangxia Ni
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, No.100 Haike Rd. Pudong New District, Shanghai, 201210, China
- University of Chinese Academy of Sciences, 100049, Beijing, China
| | - Yongfei Ren
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, No.100 Haike Rd. Pudong New District, Shanghai, 201210, China
- University of Chinese Academy of Sciences, 100049, Beijing, China
| | - Tonghui Su
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, No.100 Haike Rd. Pudong New District, Shanghai, 201210, China
- University of Chinese Academy of Sciences, 100049, Beijing, China
| | - Jia Zhou
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, No.100 Haike Rd. Pudong New District, Shanghai, 201210, China
- University of Chinese Academy of Sciences, 100049, Beijing, China
| | - Chaoying Fu
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, No.100 Haike Rd. Pudong New District, Shanghai, 201210, China
| | - Yi Lu
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, No.100 Haike Rd. Pudong New District, Shanghai, 201210, China
- University of Chinese Academy of Sciences, 100049, Beijing, China
| | - De'an Li
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, No.100 Haike Rd. Pudong New District, Shanghai, 201210, China
- University of Chinese Academy of Sciences, 100049, Beijing, China
| | - Jing Zhao
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, No.100 Haike Rd. Pudong New District, Shanghai, 201210, China
- University of Chinese Academy of Sciences, 100049, Beijing, China
| | - Yunxia Li
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, No.100 Haike Rd. Pudong New District, Shanghai, 201210, China
| | - Yaoyang Zhang
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, No.100 Haike Rd. Pudong New District, Shanghai, 201210, China
| | - Yanshan Fang
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, No.100 Haike Rd. Pudong New District, Shanghai, 201210, China
| | - Nan Liu
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, No.100 Haike Rd. Pudong New District, Shanghai, 201210, China
| | - Yang Geng
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, No.100 Haike Rd. Pudong New District, Shanghai, 201210, China.
| | - Yelin Chen
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, No.100 Haike Rd. Pudong New District, Shanghai, 201210, China.
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Metamorphism in TDP-43 prion-like domain determines chaperone recognition. Nat Commun 2023; 14:466. [PMID: 36709343 PMCID: PMC9884275 DOI: 10.1038/s41467-023-36023-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Accepted: 01/12/2023] [Indexed: 01/29/2023] Open
Abstract
The RNA binding protein TDP-43 forms cytoplasmic inclusions via its C-terminal prion-like domain in several neurodegenerative diseases. Aberrant TDP-43 aggregation arises upon phase de-mixing and transitions from liquid to solid states, following still unknown structural conversions which are primed by oxidative stress and chaperone inhibition. Despite the well-established protective roles for molecular chaperones against protein aggregation pathologies, knowledge on the determinants of chaperone recognition in disease-related prions is scarce. Here we show that chaperones and co-chaperones primarily recognize the structured elements in TDP-43´s prion-like domain. Significantly, while HSP70 and HSP90 chaperones promote TDP-43 phase separation, co-chaperones from the three classes of the large human HSP40 family (namely DNAJA2, DNAJB1, DNAJB4 and DNAJC7) show strikingly different effects on TDP-43 de-mixing. Dismantling of the second helical element in TDP-43 prion-like domain by methionine sulfoxidation impacts phase separation and amyloid formation, abrogates chaperone recognition and alters phosphorylation by casein kinase-1δ. Our results show that metamorphism in the post-translationally modified TDP-43 prion-like domain encodes determinants that command mechanisms with major relevance in disease.
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Valdebenito-Maturana B, Rojas-Tapia MI, Carrasco M, Tapia JC. Dysregulated Expression of Transposable Elements in TDP-43 M337V Human Motor Neurons That Recapitulate Amyotrophic Lateral Sclerosis In Vitro. Int J Mol Sci 2022; 23:ijms232416222. [PMID: 36555863 PMCID: PMC9784876 DOI: 10.3390/ijms232416222] [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: 11/03/2022] [Revised: 12/01/2022] [Accepted: 12/02/2022] [Indexed: 12/24/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a disease that progressively annihilates spinal cord motor neurons, causing severe motor decline and death. The disease is divided into familial and sporadic ALS. Mutations in the TAR DNA binding protein 43 (TDP-43) have been involved in the pathological emergence and progression of ALS, although the molecular mechanisms eliciting the disease are unknown. Transposable elements (TEs) and DNA sequences capable of transposing within the genome become dysregulated and transcribed in the presence of TDP-43 mutations. We performed RNA-Seq in human motor neurons (iMNs) derived from induced pluripotent stem cells (iPSCs) from TDP-43 wild-type-iMNs-TDP-43WT-and mutant-iMNs-TDP-43M337V-genotypes at 7 and 14 DIV, and, with state-of-the-art bioinformatic tools, analyzed whether TDP-43M337V alters both gene expression and TE activity. Our results show that TDP-43M337V induced global changes in the gene expression and TEs levels at all in vitro stages studied. Interestingly, many genetic pathways overlapped with that of the TEs activity, suggesting that TEs control the expression of several genes. TEs correlated with genes that played key roles in the extracellular matrix and RNA processing: all the regulatory pathways affected in ALS. Thus, the loss of TE regulation is present in TDP-43 mutations and is a critical determinant of the disease in human motor neurons. Overall, our results support the evidence that indicates TEs are critical regulatory sequences contributing to ALS neurodegeneration.
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Affiliation(s)
- Braulio Valdebenito-Maturana
- Instituto de Investigación Interdisciplinaria, Vicerrectoría Académica, Universidad de Talca, Campus Talca, Talca 3460000, Chile
| | | | - Mónica Carrasco
- Escuela de Medicina, Universidad de Talca, Campus Talca, Talca 3460000, Chile
- Correspondence: (M.C.); (J.C.T.)
| | - Juan Carlos Tapia
- Escuela de Medicina, Universidad de Talca, Campus Talca, Talca 3460000, Chile
- Correspondence: (M.C.); (J.C.T.)
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Sekar D, Tusubira D, Ross K. Corrigendum: TDP-43 and NEAT long non-coding RNA: Roles in neurodegenerative disease. Front Cell Neurosci 2022; 16:1108593. [PMID: 36589289 PMCID: PMC9800965 DOI: 10.3389/fncel.2022.1108593] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2022] [Accepted: 12/02/2022] [Indexed: 12/23/2022] Open
Abstract
[This corrects the article DOI: 10.3389/fncel.2022.954912.].
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Affiliation(s)
- Durairaj Sekar
- Centre for Cellular and Molecular Research, Saveetha Dental College and Hospitals, Saveetha Institute of Medical and Technical Sciences (SIMATS), Saveetha University, Chennai, India
| | - Deusdedit Tusubira
- Department of Biochemistry, Mbarara University of Science and Technology, Mbarara, Uganda,*Correspondence: Deusdedit Tusubira ✉
| | - Kehinde Ross
- School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Liverpool, United Kingdom,Institute for Health Research, Liverpool John Moores University, Liverpool, United Kingdom,Kehinde Ross ✉
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Different Intermolecular Interactions Drive Nonpathogenic Liquid-Liquid Phase Separation and Potentially Pathogenic Fibril Formation by TDP-43. Int J Mol Sci 2022; 23:ijms232315227. [PMID: 36499553 PMCID: PMC9741235 DOI: 10.3390/ijms232315227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Revised: 11/03/2022] [Accepted: 11/18/2022] [Indexed: 12/07/2022] Open
Abstract
The liquid-liquid phase separation (LLPS) of proteins has been found ubiquitously in eukaryotic cells, and is critical in the control of many biological processes by forming a temporary condensed phase with different bimolecular components. TDP-43 is recruited to stress granules in cells and is the main component of TDP-43 granules and proteinaceous amyloid inclusions in patients with amyotrophic lateral sclerosis (ALS). TDP-43 low complexity domain (LCD) is able to de-mix in solution, forming the protein condensed droplets, and amyloid aggregates would form from the droplets after incubation. The molecular interactions regulating TDP-43 LCD LLPS were investigated at the protein fusion equilibrium stage, when the droplets stopped growing after incubation. We found the molecules in the droplet were still liquid-like, but with enhanced intermolecular helix-helix interactions. The protein would only start to aggregate after a lag time and aggregate slower than at the condition when the protein does not phase separately into the droplets, or the molecules have a reduced intermolecular helix-helix interaction. In the protein condensed droplets, a structural transition intermediate toward protein aggregation was discovered involving a decrease in the intermolecular helix-helix interaction and a reduction in the helicity. Our results therefore indicate that different intermolecular interactions drive LLPS and fibril formation. The discovery that TDP-43 LCD aggregation was faster through the pathway without the first protein phase separation supports that LLPS and the intermolecular helical interaction could help maintain the stability of TDP-43 LCD.
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37
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Sekar D, Tusubira D, Ross K. TDP-43 and NEAT long non-coding RNA: Roles in neurodegenerative disease. Front Cell Neurosci 2022; 16:954912. [PMID: 36385948 PMCID: PMC9650703 DOI: 10.3389/fncel.2022.954912] [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: 05/27/2022] [Accepted: 10/11/2022] [Indexed: 01/03/2023] Open
Abstract
Understanding and ameliorating neurodegenerative diseases represents a key challenge for supporting the health span of the aging population. Diverse protein aggregates have been implicated in such neurodegenerative disorders, including amyloid-β, α-synuclein, tau, fused in sarcoma (FUS), and transactivation response element (TAR) DNA-binding protein 43 (TDP-43). Recent years have seen significant growth in our mechanistic knowledge of relationships between these proteins and some of the membrane-less nuclear structures that fulfill key roles in the cell function. These include the nucleolus, nuclear speckles, and paraspeckles. The ability of macromolecular protein:RNA complexes to partition these nuclear condensates through biophysical processes that involve liquid-liquid phase separation (LLPS) has also gained attention recently. The paraspeckle, which is scaffolded by the architectural long-non-coding RNA nuclear enriched abundant transcript 1 (NEAT1) plays central roles in RNA processing and metabolism and has been linked dynamically to TDP-43. In this mini-review, we outline essential early and recent insights in relation to TDP-43 proteinopathies. We then appraise the relationships between TDP-43 and NEAT1 in the context of neuronal paraspeckles and neuronal stress. We highlight key areas for investigation based on recent advances in our understanding of how TDP-43 affects neuronal function, especially in relation to messenger ribosomal nucleic acid (mRNA) splicing. Finally, we offer perspectives that should be considered for translational pipelines in order to improve health outcomes for the management of neurodegenerative diseases.
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Affiliation(s)
- Durairaj Sekar
- Centre for Cellular and Molecular Research, Saveetha Dental College and Hospitals, Saveetha Institute of Medical and Technical Sciences (SIMATS), Saveetha University, Chennai, India
| | - Deusdedit Tusubira
- Department of Biochemistry, Mbarara University of Science and Technology, Mbarara, Uganda,*Correspondence: Deusdedit Tusubira, ; orcid.org/0000-0002-4698-424X
| | - Kehinde Ross
- School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Liverpool, United Kingdom,Institute for Health Research, Liverpool John Moores University, Liverpool, United Kingdom,Kehinde Ross, ; orcid.org/0000-0003-0252-1152
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38
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Stress induced TDP-43 mobility loss independent of stress granules. Nat Commun 2022; 13:5480. [PMID: 36123343 PMCID: PMC9485239 DOI: 10.1038/s41467-022-32939-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Accepted: 08/24/2022] [Indexed: 11/25/2022] Open
Abstract
TAR DNA binding protein 43 (TDP-43) is closely related to the pathogenesis of amyotrophic lateral sclerosis (ALS) and translocates to stress granules (SGs). The role of SGs as aggregation-promoting “crucibles” for TDP-43, however, is still under debate. We analyzed TDP-43 mobility and localization under different stress and recovery conditions using live cell single-molecule tracking and super-resolution microscopy. Besides reduced mobility within SGs, a stress induced decrease of TDP-43 mobility in the cytoplasm and the nucleus was observed. Stress removal led to a recovery of TDP-43 mobility, which strongly depended on the stress duration. ‘Stimulated-emission depletion microscopy’ (STED) and ‘tracking and localization microscopy’ (TALM) revealed not only TDP-43 substructures within stress granules but also numerous patches of slow TDP-43 species throughout the cytoplasm. This work provides insights into the aggregation of TDP-43 in living cells and provide evidence suggesting that TDP-43 oligomerization and aggregation takes place in the cytoplasm separate from SGs. Amyotrophic Lateral Sclerosis related TDP-43 protein translocates to stress granules with a concomitant reduction in mobility. Here, the authors use single molecule tracking and find a stress-induced reduction in TDP-43 mobility also in the cytoplasm potentially relevant for TDP-43 aggregation.
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39
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Tran NN, Lee BH. Functional implication of ubiquitinating and deubiquitinating mechanisms in TDP-43 proteinopathies. Front Cell Dev Biol 2022; 10:931968. [PMID: 36158183 PMCID: PMC9500471 DOI: 10.3389/fcell.2022.931968] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Accepted: 08/23/2022] [Indexed: 11/15/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease in which motor neurons in spinal cord and motor cortex are progressively lost. About 15% cases of ALS also develop the frontotemporal dementia (FTD), in which the frontotemporal lobar degeneration (FTLD) occurs in the frontal and temporal lobes of the brain. Among the pathologic commonalities in ALS and FTD is ubiquitin-positive cytoplasmic aggregation of TDP-43 that may reflect both its loss-of-function and gain-of-toxicity from proteostasis impairment. Deep understanding of how protein quality control mechanisms regulate TDP-43 proteinopathies still remains elusive. Recently, a growing body of evidence indicates that ubiquitinating and deubiquitinating pathways are critically engaged in the fate decision of aberrant or pathological TDP-43 proteins. E3 ubiquitin ligases coupled with deubiquitinating enzymes may influence the TDP-43-associated proteotoxicity through diverse events, such as protein stability, translocation, and stress granule or inclusion formation. In this article, we recapitulate our current understanding of how ubiquitinating and deubiquitinating mechanisms can modulate TDP-43 protein quality and its pathogenic nature, thus shedding light on developing targeted therapies for ALS and FTD by harnessing protein degradation machinery.
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Affiliation(s)
- Non-Nuoc Tran
- Department of New Biology, Daegu-Gyeongbuk Institute of Science and Technology (DGIST), Daegu, South Korea
| | - Byung-Hoon Lee
- Department of New Biology, Daegu-Gyeongbuk Institute of Science and Technology (DGIST), Daegu, South Korea
- Department of New Biology Research Center (NBRC), Daegu-Gyeongbuk Institute of Science and Technology (DGIST), Daegu, South Korea
- *Correspondence: Byung-Hoon Lee,
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40
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Motataianu A, Serban G, Barcutean L, Balasa R. Oxidative Stress in Amyotrophic Lateral Sclerosis: Synergy of Genetic and Environmental Factors. Int J Mol Sci 2022; 23:ijms23169339. [PMID: 36012603 PMCID: PMC9409178 DOI: 10.3390/ijms23169339] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 08/11/2022] [Accepted: 08/17/2022] [Indexed: 12/12/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a grievous neurodegenerative disease whose survival is limited to only a few years. In spite of intensive research to discover the underlying mechanisms, the results are fairly inconclusive. Multiple hypotheses have been regarded, including genetic, molecular, and cellular processes. Notably, oxidative stress has been demonstrated to play a crucial role in ALS pathogenesis. In addition to already recognized and exhaustively studied genetic mutations involved in oxidative stress production, exposure to various environmental factors (e.g., electromagnetic fields, solvents, pesticides, heavy metals) has been suggested to enhance oxidative damage. This review aims to describe the main processes influenced by the most frequent genetic mutations and environmental factors concurring in oxidative stress occurrence in ALS and the potential therapeutic molecules capable of diminishing the ALS related pro-oxidative status.
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Affiliation(s)
- Anca Motataianu
- Department of Neurology, “George Emil Palade” University of Medicine, Pharmacy, Science and Technology of Targu Mures, 540136 Targu Mures, Romania
- 1st Neurology Clinic, Emergency Clinical County Hospital Targu Mures, 540136 Targu Mures, Romania
| | - Georgiana Serban
- Doctoral School, “George Emil Palade” University of Medicine, Pharmacy, Science, and Technology of Targu Mures, 540142 Targu Mures, Romania
- Correspondence: ; Tel.: +40-0724-051-516
| | - Laura Barcutean
- Department of Neurology, “George Emil Palade” University of Medicine, Pharmacy, Science and Technology of Targu Mures, 540136 Targu Mures, Romania
- 1st Neurology Clinic, Emergency Clinical County Hospital Targu Mures, 540136 Targu Mures, Romania
| | - Rodica Balasa
- Department of Neurology, “George Emil Palade” University of Medicine, Pharmacy, Science and Technology of Targu Mures, 540136 Targu Mures, Romania
- 1st Neurology Clinic, Emergency Clinical County Hospital Targu Mures, 540136 Targu Mures, Romania
- Doctoral School, “George Emil Palade” University of Medicine, Pharmacy, Science, and Technology of Targu Mures, 540142 Targu Mures, Romania
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41
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Duan L, Zaepfel BL, Aksenova V, Dasso M, Rothstein JD, Kalab P, Hayes LR. Nuclear RNA binding regulates TDP-43 nuclear localization and passive nuclear export. Cell Rep 2022; 40:111106. [PMID: 35858577 PMCID: PMC9345261 DOI: 10.1016/j.celrep.2022.111106] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 03/26/2022] [Accepted: 06/27/2022] [Indexed: 11/27/2022] Open
Abstract
Nuclear clearance of the RNA-binding protein TDP-43 is a hallmark of neurodegeneration and an important therapeutic target. Our current understanding of TDP-43 nucleocytoplasmic transport does not fully explain its predominantly nuclear localization or mislocalization in disease. Here, we show that TDP-43 exits nuclei by passive diffusion, independent of facilitated mRNA export. RNA polymerase II blockade and RNase treatment induce TDP-43 nuclear efflux, suggesting that nuclear RNAs sequester TDP-43 in nuclei and limit its availability for passive export. Induction of TDP-43 nuclear efflux by short, GU-rich oligomers (presumably by outcompeting TDP-43 binding to endogenous nuclear RNAs), and nuclear retention conferred by splicing inhibition, demonstrate that nuclear TDP-43 localization depends on binding to GU-rich nuclear RNAs. Indeed, RNA-binding domain mutations markedly reduce TDP-43 nuclear localization and abolish transcription blockade-induced nuclear efflux. Thus, the nuclear abundance of GU-RNAs, dictated by the balance of transcription, pre-mRNA processing, and RNA export, regulates TDP-43 nuclear localization.
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Affiliation(s)
- Lauren Duan
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Benjamin L Zaepfel
- Biochemistry, Cellular and Molecular Biology Program, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Vasilisa Aksenova
- Division of Molecular and Cellular Biology, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Mary Dasso
- Division of Molecular and Cellular Biology, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Jeffrey D Rothstein
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Petr Kalab
- Department of Chemical and Biomolecular Engineering, Whiting School of Engineering, Johns Hopkins University, Baltimore, MD 21218, USA.
| | - Lindsey R Hayes
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
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Paron F, Barattucci S, Cappelli S, Romano M, Berlingieri C, Stuani C, Laurents D, Mompeán M, Buratti E. Unravelling the toxic effects mediated by the neurodegenerative disease-associated S375G mutation of TDP-43 and its S375E phosphomimetic variant. J Biol Chem 2022; 298:102252. [PMID: 35835219 PMCID: PMC9364110 DOI: 10.1016/j.jbc.2022.102252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2022] [Revised: 06/23/2022] [Accepted: 06/25/2022] [Indexed: 12/05/2022] Open
Abstract
TAR DNA-binding protein 43 (TDP-43) is a nucleic acid–binding protein found in the nucleus that accumulates in the cytoplasm under pathological conditions, leading to proteinopathies, such as frontotemporal dementia and ALS. An emerging area of TDP-43 research is represented by the study of its post-translational modifications, the way they are connected to disease-associated mutations, and what this means for pathological processes. Recently, we described a novel mutation in TDP-43 in an early onset ALS case that was affecting a potential phosphorylation site in position 375 (S375G). A preliminary characterization showed that both the S375G mutation and its phosphomimetic variant, S375E, displayed altered nuclear–cytoplasmic distribution and cellular toxicity. To better investigate these effects, here we established cell lines expressing inducible WT, S375G, and S375E TDP-43 variants. Interestingly, we found that these mutants do not seem to affect well-studied aspects of TDP-43, such as RNA splicing or autoregulation, or protein conformation, dynamics, or aggregation, although they do display dysmorphic nuclear shape and cell cycle alterations. In addition, RNA-Seq analysis of these cell lines showed that although the disease-associated S375G mutation and its phosphomimetic S375E variant regulate distinct sets of genes, they have a common target in mitochondrial apoptotic genes. Taken together, our data strongly support the growing evidence that alterations in TDP-43 post-translational modifications can play a potentially important role in disease pathogenesis and provide a further link between TDP-43 pathology and mitochondrial health.
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Affiliation(s)
- Francesca Paron
- Molecular Pathology, International Centre for Genetic and Engineering Biotechnology (ICGEB), Trieste, Italy
| | - Simone Barattucci
- Molecular Pathology, International Centre for Genetic and Engineering Biotechnology (ICGEB), Trieste, Italy
| | - Sara Cappelli
- Molecular Pathology, International Centre for Genetic and Engineering Biotechnology (ICGEB), Trieste, Italy
| | - Maurizio Romano
- Department of Life Sciences, University of Trieste, Trieste, Italy
| | - Christian Berlingieri
- Molecular Pathology, International Centre for Genetic and Engineering Biotechnology (ICGEB), Trieste, Italy
| | - Cristiana Stuani
- Molecular Pathology, International Centre for Genetic and Engineering Biotechnology (ICGEB), Trieste, Italy
| | - Douglas Laurents
- "Rocasolano" Institute for Physical Chemistry, Spanish National Research Council, Serrano 119, 28006, Madrid, Spain
| | - Miguel Mompeán
- "Rocasolano" Institute for Physical Chemistry, Spanish National Research Council, Serrano 119, 28006, Madrid, Spain
| | - Emanuele Buratti
- Molecular Pathology, International Centre for Genetic and Engineering Biotechnology (ICGEB), Trieste, Italy.
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43
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Zhou X, Sumrow L, Tashiro K, Sutherland L, Liu D, Qin T, Kato M, Liszczak G, McKnight SL. Mutations linked to neurological disease enhance self-association of low-complexity protein sequences. Science 2022; 377:eabn5582. [PMID: 35771920 PMCID: PMC9610444 DOI: 10.1126/science.abn5582] [Citation(s) in RCA: 32] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Protein domains of low sequence complexity do not fold into stable, three-dimensional structures. Nevertheless, proteins with these sequences assist in many aspects of cell organization, including assembly of nuclear and cytoplasmic structures not surrounded by membranes. The dynamic nature of these cellular assemblies is caused by the ability of low-complexity domains (LCDs) to transiently self-associate through labile, cross-β structures. Mechanistic studies useful for the study of LCD self-association have evolved over the past decade in the form of simple assays of phase separation. Here, we have used such assays to demonstrate that the interactions responsible for LCD self-association can be dictated by labile protein structures poised close to equilibrium between the folded and unfolded states. Furthermore, missense mutations causing Charcot-Marie-Tooth disease, frontotemporal dementia, and Alzheimer's disease manifest their pathophysiology in vitro and in cultured cell systems by enhancing the stability of otherwise labile molecular structures formed upon LCD self-association.
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Hayes LR, Kalab P. Emerging Therapies and Novel Targets for TDP-43 Proteinopathy in ALS/FTD. Neurotherapeutics 2022; 19:1061-1084. [PMID: 35790708 PMCID: PMC9587158 DOI: 10.1007/s13311-022-01260-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/03/2022] [Indexed: 10/17/2022] Open
Abstract
Nuclear clearance and cytoplasmic mislocalization of the essential RNA binding protein, TDP-43, is a pathologic hallmark of amyotrophic lateral sclerosis, frontotemporal dementia, and related neurodegenerative disorders collectively termed "TDP-43 proteinopathies." TDP-43 mislocalization causes neurodegeneration through both loss and gain of function mechanisms. Loss of TDP-43 nuclear RNA processing function destabilizes the transcriptome by multiple mechanisms including disruption of pre-mRNA splicing, the failure of repression of cryptic exons, and retrotransposon activation. The accumulation of cytoplasmic TDP-43, which is prone to aberrant liquid-liquid phase separation and aggregation, traps TDP-43 in the cytoplasm and disrupts a host of downstream processes including the trafficking of RNA granules, local translation within axons, and mitochondrial function. In this review, we will discuss the TDP-43 therapy development pipeline, beginning with therapies in current and upcoming clinical trials, which are primarily focused on accelerating the clearance of TDP-43 aggregates. Then, we will look ahead to emerging strategies from preclinical studies, first from high-throughput genetic and pharmacologic screens, and finally from mechanistic studies focused on the upstream cause(s) of TDP-43 disruption in ALS/FTD. These include modulation of stress granule dynamics, TDP-43 nucleocytoplasmic shuttling, RNA metabolism, and correction of aberrant splicing events.
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Affiliation(s)
- Lindsey R Hayes
- Johns Hopkins School of Medicine, Dept. of Neurology, Baltimore, MD, USA.
| | - Petr Kalab
- Whiting School of Engineering, Johns Hopkins University, Baltimore, MD, USA
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Shenouda M, Xiao S, MacNair L, Lau A, Robertson J. A C-Terminally Truncated TDP-43 Splice Isoform Exhibits Neuronal Specific Cytoplasmic Aggregation and Contributes to TDP-43 Pathology in ALS. Front Neurosci 2022; 16:868556. [PMID: 35801182 PMCID: PMC9253772 DOI: 10.3389/fnins.2022.868556] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Accepted: 05/24/2022] [Indexed: 01/01/2023] Open
Abstract
Neuronal cytoplasmic aggregation and ubiquitination of TDP-43 is the most common disease pathology linking Amyotrophic Lateral Sclerosis (ALS) and frontotemporal lobar degeneration (FTLD). TDP-43 pathology is characterized by the presence of low molecular weight TDP-43 species generated through proteolytic cleavage and/or abnormal RNA processing events. In addition to N-terminally truncated TDP-43 species, it has become evident that C-terminally truncated variants generated through alternative splicing in exon 6 also contribute to the pathophysiology of ALS/FTLD. Three such variants are listed in UCSD genome browser each sharing the same C-terminal unique sequence of 18 amino acids which has been shown to contain a putative nuclear export sequence. Here we have identified an additional C-terminally truncated variant of TDP-43 in human spinal cord tissue. This variant, called TDP43C-spl, is generated through use of non-canonical splice sites in exon 6, skipping 1,020 bp and encoding a 272 aa protein lacking the C-terminus with the first 256 aa identical to full-length TDP-43 and the same 18 amino acid C-terminal unique sequence. Ectopic expression studies in cells revealed that TDP43C-spl was localized to the nucleus in astrocytic and microglial cell lines but formed cytoplasmic ubiquitinated aggregates in neuronal cell lines. An antibody raised to the unique 18 amino acid sequence showed elevated levels of C-terminally truncated variants in ALS spinal cord tissues, and co-labeled TDP-43 pathology in disease affected spinal motor neurons. The retention of this 18 amino acid sequence among several C-terminally truncated TDP-43 variants suggests important functional relevance. Our studies of TDP43C-spl suggest this may be related to the selective vulnerability of neurons to TDP-43 pathology and cell-subtype differences in nuclear export.
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Affiliation(s)
- Marc Shenouda
- Tanz Centre for Research in Neurodegenerative Diseases, Toronto, ON, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
| | - Shangxi Xiao
- Tanz Centre for Research in Neurodegenerative Diseases, Toronto, ON, Canada
| | - Laura MacNair
- Tanz Centre for Research in Neurodegenerative Diseases, Toronto, ON, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
| | - Agnes Lau
- Tanz Centre for Research in Neurodegenerative Diseases, Toronto, ON, Canada
| | - Janice Robertson
- Tanz Centre for Research in Neurodegenerative Diseases, Toronto, ON, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
- *Correspondence: Janice Robertson
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Prtenjaca N, Rob M, Alam MS, Markovinovic A, Stuani C, Buratti E, Munitic I. Optineurin Deficiency and Insufficiency Lead to Higher Microglial TDP-43 Protein Levels. Int J Mol Sci 2022; 23:ijms23126829. [PMID: 35743272 PMCID: PMC9224222 DOI: 10.3390/ijms23126829] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Revised: 06/17/2022] [Accepted: 06/17/2022] [Indexed: 11/16/2022] Open
Abstract
Mutations in optineurin, a ubiquitin-binding adaptor protein, cause amyotrophic lateral sclerosis (ALS), a fatal neurodegenerative disease of motor neurons linked to chronic inflammation and protein aggregation. The majority of ALS patients, including those carrying the optineurin mutations, exhibit cytoplasmic mislocalization, ubiquitination, and aggregation of nuclear TAR DNA-binding protein 43 kDa (TDP-43). To address the crosstalk between optineurin and TDP-43, we generated optineurin knockout (KO) neuronal and microglial cell lines using the CRISPR/Cas9 approach. Interestingly, we observed that loss of optineurin resulted in elevated TDP-43 protein expression in microglial BV2 but not neuronal Neuro 2a and NSC-34 cell lines. No changes were observed at the mRNA level, suggesting that this increase was post-translationally regulated. To confirm this observation in primary cells, we then used microglia and macrophages from an optineurin loss-of-function mouse model that lacks the C-terminal ubiquitin-binding region (Optn470T), mimicking optineurin truncations in ALS patients. As observed in the BV2 cells, we also found elevated basal levels of TDP-43 protein in Optn470T microglia and bone marrow-derived macrophages. To test if inflammation could further enhance TDP-43 accumulation in cells lacking functional optineurin, we stimulated them with lipopolysaccharide (LPS), and we observed a significant increase in TDP-43 expression following LPS treatment of WT cells. However, this was absent in both BV2 Optn KO and primary Optn470T microglia, which exhibited the same elevated TDP-43 levels as in basal conditions. Furthermore, we did not observe nuclear TDP-43 depletion or cytoplasmic aggregate formation in either Optn470T microglia or LPS-treated WT or Optn470T microglia. Taken together, our results show that optineurin deficiency and insufficiency post-translationally upregulate microglial TDP-43 protein levels and that elevated TDP-43 levels in cells lacking functional optineurin could not be further increased by an inflammatory stimulus, suggesting the presence of a plateau.
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Affiliation(s)
- Nikolina Prtenjaca
- Laboratory of Molecular Immunology, Department of Biotechnology, University of Rijeka, R. Matejcic 2, 51000 Rijeka, Croatia; (N.P.); (M.R.); (A.M.)
| | - Matea Rob
- Laboratory of Molecular Immunology, Department of Biotechnology, University of Rijeka, R. Matejcic 2, 51000 Rijeka, Croatia; (N.P.); (M.R.); (A.M.)
- Department of Medical Genetics, Dementia Research Institute, Cambridge Institute for Medical Research (CIMR), University of Cambridge, Cambridge CB2 0XY, UK
| | - Muhammad S. Alam
- Laboratory of Immune Cell Biology, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD 20892, USA;
| | - Andrea Markovinovic
- Laboratory of Molecular Immunology, Department of Biotechnology, University of Rijeka, R. Matejcic 2, 51000 Rijeka, Croatia; (N.P.); (M.R.); (A.M.)
- Department of Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London SE5 9RT, UK
| | - Cristiana Stuani
- International Centre for Genetic Engineering and Biotechnology (ICGEB), Padriciano 99, 34149 Trieste, Italy; (C.S.); (E.B.)
| | - Emanuele Buratti
- International Centre for Genetic Engineering and Biotechnology (ICGEB), Padriciano 99, 34149 Trieste, Italy; (C.S.); (E.B.)
| | - Ivana Munitic
- Laboratory of Molecular Immunology, Department of Biotechnology, University of Rijeka, R. Matejcic 2, 51000 Rijeka, Croatia; (N.P.); (M.R.); (A.M.)
- Correspondence:
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Vishal SS, Wijegunawardana D, Salaikumaran MR, Gopal PP. Sequence Determinants of TDP-43 Ribonucleoprotein Condensate Formation and Axonal Transport in Neurons. Front Cell Dev Biol 2022; 10:876893. [PMID: 35646935 PMCID: PMC9133736 DOI: 10.3389/fcell.2022.876893] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Accepted: 04/21/2022] [Indexed: 11/17/2022] Open
Abstract
Mutations in TDP-43, a RNA-binding protein with multiple functions in RNA metabolism, cause amyotrophic lateral sclerosis (ALS), but it is uncertain how defects in RNA biology trigger motor neuron degeneration. TDP-43 is a major constituent of ribonucleoprotein (RNP) granules, phase separated biomolecular condensates that regulate RNA splicing, mRNA transport, and translation. ALS-associated TDP-43 mutations, most of which are found in the low complexity domain, promote aberrant liquid to solid phase transitions and impair the dynamic liquid-like properties and motility of RNP transport granules in neurons. Here, we perform a comparative analysis of ALS-linked mutations and TDP-43 variants in order to identify critical structural elements, aromatic and charged residues that are key determinants of TDP-43 RNP transport and condensate formation in neurons. We find that A315T and Q343R disease-linked mutations and substitutions of aromatic residues within the α-helical domain and LARKS, show the most severe defects in TDP-43 RNP granule transport and impair both anterograde and retrograde motility. F313L and F313-6L/Y substitutions of one or both phenylalanine residues in LARKS suggest the aromatic rings are important for TDP-43 RNP transport. Similarly, W334F/L substitutions of the tryptophan residue in the α-helical domain, impair TDP-43 RNP motility (W334L) or anterograde transport (W334F). We also show that R293A and R293K mutations, which disrupt the only RGG in the LCD, profoundly reduce long-range, directed transport and net velocity of TDP-43 RNP granules. In the disordered regions flanking the α-helical domain, we find that F283Y, F397Y or Y374F substitutions of conserved GF/G and SYS motifs, also impair anterograde and/or retrograde motility, possibly by altering hydrophobicity. Similarly, ALS-linked mutations in disordered regions distant from the α-helical domain also show anterograde transport deficits, consistent with previous findings, but these mutations are less severe than A315T and Q343R. Overall our findings demonstrate that the conserved α-helical domain, phenylalanine residues within LARKS and RGG motif are key determinants of TDP-43 RNP transport, suggesting they may mediate efficient recruitment of motors and adaptor proteins. These results offer a possible mechanism underlying ALS-linked TDP-43 defects in axonal transport and homeostasis.
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Affiliation(s)
- Sonali S. Vishal
- Department of Pathology, Yale School of Medicine, New Haven, CT, United States
| | | | | | - Pallavi P. Gopal
- Department of Pathology, Yale School of Medicine, New Haven, CT, United States
- Program in Cellular Neuroscience, Neurodegeneration, and Repair, Yale School of Medicine, New Haven, CT, United States
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Hu L, Mao S, Lin L, Bai G, Liu B, Mao J. Stress granules in the spinal muscular atrophy and amyotrophic lateral sclerosis: The correlation and promising therapy. Neurobiol Dis 2022; 170:105749. [PMID: 35568100 DOI: 10.1016/j.nbd.2022.105749] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2022] [Revised: 03/27/2022] [Accepted: 05/05/2022] [Indexed: 10/18/2022] Open
Abstract
Increasing genetic and biochemical evidence has broadened our view of the pathomechanisms that lead to Spinal muscular atrophy (SMA) and Amyotrophic lateral sclerosis (ALS), two fatal neurodegenerative diseases with similar symptoms and causes. Stress granules are dynamic cytosolic storage hubs for mRNAs in response to stress exposures, that are evolutionarily conserved cytoplasmic RNA granules in somatic cells. A lot of previous studies have shown that the impaired stress granules are crucial events in SMA/ALS pathogenesis. In this review, we described the key stress granules related RNA binding proteins (SMN, TDP-43, and FUS) involved in SMA/ALS, summarized the reported mutations in these RNA binding proteins involved in SMA/ALS pathogenesis, and discussed the mechanisms through which stress granules dynamics participate in the diseases. Meanwhile, we described the applications and limitation of current therapies targeting SMA/ALS. We futher proposed the promising targets on stress granules in the future therapeutic interventions of SMA/ALS.
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Affiliation(s)
- LiDan Hu
- the Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou 310052, China.
| | - Shanshan Mao
- the Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou 310052, China
| | - Li Lin
- the Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou 310052, China
| | - Guannan Bai
- the Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou 310052, China
| | - Bingjie Liu
- State Key Laboratory of Membrane Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Jianhua Mao
- the Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou 310052, China
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49
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Li R, Singh R, Kashav T, Yang C, Sharma RD, Lynn AM, Prasad R, Prakash A, Kumar V. Computational Insights of Unfolding of N-Terminal Domain of TDP-43 Reveal the Conformational Heterogeneity in the Unfolding Pathway. Front Mol Neurosci 2022; 15:822863. [PMID: 35548668 PMCID: PMC9083116 DOI: 10.3389/fnmol.2022.822863] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Accepted: 03/22/2022] [Indexed: 02/05/2023] Open
Abstract
TDP-43 proteinopathies is a disease hallmark that characterizes amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD). The N-terminal domain of TDP-43 (NTD) is important to both TDP-43 physiology and TDP-43 proteinopathy. However, its folding and dimerization process is still poorly characterized. In the present study, we have investigated the folding/unfolding of NTD employing all-atom molecular dynamics (MD) simulations in 8 M dimethylsulfoxide (DMSO) at high temperatures. The MD results showed that the unfolding of the NTD at high temperature evolves through the formation of a number of conformational states differing in their stability and free energy. The presence of structurally heterogeneous population of intermediate ensembles was further characterized by the different extents of solvent exposure of Trp80 during unfolding. We suggest that these non-natives unfolded intermediate ensembles may facilitate NTD oligomerization and subsequently TDP-43 oligomerization, which might lead to the formation of irreversible pathological aggregates, characteristics of disease pathogenesis.
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Affiliation(s)
- Ruiting Li
- School of Engineering, Guangzhou College of Technology and Business, Guangzhou, China
| | - Ruhar Singh
- School of Computational & Integrative Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Tara Kashav
- Department of Life Science, Central University of South Bihar, Gaya, India
| | - ChunMin Yang
- School of Engineering, Guangzhou College of Technology and Business, Guangzhou, China
| | - Ravi Datta Sharma
- Amity Institute of Biotechnology, Amity University Haryana, Gurgaon, India
| | - Andrew M. Lynn
- School of Computational & Integrative Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Rajendra Prasad
- Amity Institute of Biotechnology, Amity University Haryana, Gurgaon, India
| | - Amresh Prakash
- Amity Institute of Integrative Sciences and Health (AIISH), Amity University Haryana, Gurgaon, India
- *Correspondence: Vijay Kumar Amresh Prakash
| | - Vijay Kumar
- Amity Institute of Neuropsychology & Neurosciences (AINN), Amity University, Noida, India
- *Correspondence: Vijay Kumar Amresh Prakash
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50
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Tello JA, Williams HE, Eppler RM, Steinhilb ML, Khanna M. Animal Models of Neurodegenerative Disease: Recent Advances in Fly Highlight Innovative Approaches to Drug Discovery. Front Mol Neurosci 2022; 15:883358. [PMID: 35514431 PMCID: PMC9063566 DOI: 10.3389/fnmol.2022.883358] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Accepted: 03/21/2022] [Indexed: 12/22/2022] Open
Abstract
Neurodegenerative diseases represent a formidable challenge to global health. As advances in other areas of medicine grant healthy living into later decades of life, aging diseases such as Alzheimer's disease (AD) and other neurodegenerative disorders can diminish the quality of these additional years, owed largely to the lack of efficacious treatments and the absence of durable cures. Alzheimer's disease prevalence is predicted to more than double in the next 30 years, affecting nearly 15 million Americans, with AD-associated costs exceeding $1 billion by 2050. Delaying onset of AD and other neurodegenerative diseases is critical to improving the quality of life for patients and reducing the burden of disease on caregivers and healthcare systems. Significant progress has been made to model disease pathogenesis and identify points of therapeutic intervention. While some researchers have contributed to our understanding of the proteins and pathways that drive biological dysfunction in disease using in vitro and in vivo models, others have provided mathematical, biophysical, and computational technologies to identify potential therapeutic compounds using in silico modeling. The most exciting phase of the drug discovery process is now: by applying a target-directed approach that leverages the strengths of multiple techniques and validates lead hits using Drosophila as an animal model of disease, we are on the fast-track to identifying novel therapeutics to restore health to those impacted by neurodegenerative disease.
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Affiliation(s)
- Judith A. Tello
- Department of Pharmacology, College of Medicine, University of Arizona, Tucson, AZ, United States
- Center of Innovation in Brain Science, Tucson, AZ, United States
| | - Haley E. Williams
- Department of Pharmacology, College of Medicine, University of Arizona, Tucson, AZ, United States
- Center of Innovation in Brain Science, Tucson, AZ, United States
| | - Robert M. Eppler
- Department of Biology, Central Michigan University, Mount Pleasant, MI, United States
| | - Michelle L. Steinhilb
- Department of Biology, Central Michigan University, Mount Pleasant, MI, United States
| | - May Khanna
- Department of Pharmacology, College of Medicine, University of Arizona, Tucson, AZ, United States
- Center of Innovation in Brain Science, Tucson, AZ, United States
- Department of Molecular Pathobiology, New York University, New York, NY, United States
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