1
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Lester E, Parker R. Tau, RNA, and RNA-Binding Proteins: Complex Interactions in Health and Neurodegenerative Diseases. Neuroscientist 2024; 30:458-472. [PMID: 36892034 DOI: 10.1177/10738584231154551] [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] [Indexed: 03/10/2023]
Abstract
The tau protein is a key contributor to multiple neurodegenerative diseases. The pathology of tau is thought to be related to tau's propensity to form self-templating fibrillar structures that allow tau fibers to propagate in the brain by prion-like mechanisms. Unresolved issues with respect to tau pathology are how the normal function of tau and its misregulation contribute to disease, how cofactors and cellular organelles influence the initiation and propagation of tau fibers, and determining the mechanism of tau toxicity. Herein, we review the connection between tau and degenerative diseases, the basis for tau fibrilization, and how that process interacts with cellular molecules and organelles. One emerging theme is that tau interacts with RNA and RNA-binding proteins, normally and in pathologic aggregates, which may provide insight into alterations in RNA regulation observed in disease.
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Affiliation(s)
- Evan Lester
- Department of Biochemistry, University of Colorado Boulder, Boulder, CO, USA
- Medical Scientist Training Program, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Roy Parker
- Department of Biochemistry, University of Colorado Boulder, Boulder, CO, USA
- Howard Hughes Medical Institute, University of Colorado, Boulder, CO, USA
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2
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Singh MK, Ryu TH, Nguyen MN, Yu K. Inhibition of high-fat diet-induced miRNA ameliorates tau toxicity in Drosophila. Biochem Biophys Res Commun 2024; 733:150446. [PMID: 39067249 DOI: 10.1016/j.bbrc.2024.150446] [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: 07/02/2024] [Revised: 07/16/2024] [Accepted: 07/23/2024] [Indexed: 07/30/2024]
Abstract
Alzheimer's disease (AD), caused by amyloid beta (Aβ) plaques and Tau tangles, is a neurodegenerative disease characterized by progressive memory impairment and cognitive dysfunction. High-fat diet (HFD), which induces type 2 diabetes, exacerbates Aβ plaque deposition in the brain. To investigate the function of HFD in Tau-mediated AD, we fed an HFD to the Drosophila Tau model and found that HFD aggravates Tau-induced neurological phenotypes. Since microRNAs (miRNAs) are biomarkers for diabetes and AD, we evaluated the expression levels of common miRNAs of HFD and AD in HFD-fed Tau model fly brains. Among the common miRNAs, the expression levels of Let-7 and miR-34 were increased. We found that the inhibition of these miRNAs alleviates Tau-mediated AD phenotypes. Our research provides valuable insights into how HFD accelerates tau toxicity. Additionally, our work highlights the therapeutic potential of targeting Let-7 and miR-34 to develop innovative treatment approaches for AD.
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Affiliation(s)
- Manish Kumar Singh
- Metabolism and Neurophysiology Research Group, Disease Target Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, 34141, Republic of Korea
| | - Tae Hoon Ryu
- Metabolism and Neurophysiology Research Group, Disease Target Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, 34141, Republic of Korea
| | - Minh Nguyet Nguyen
- Metabolism and Neurophysiology Research Group, Disease Target Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, 34141, Republic of Korea; Department of Bioscience, University of Science and Technology (UST), Daejeon, 34113, Republic of Korea
| | - Kweon Yu
- Metabolism and Neurophysiology Research Group, Disease Target Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, 34141, Republic of Korea; Department of Bioscience, University of Science and Technology (UST), Daejeon, 34113, Republic of Korea.
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3
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Nithianandam V, Sarkar S, Feany MB. Pathways controlling neurotoxicity and proteostasis in mitochondrial complex I deficiency. Hum Mol Genet 2024; 33:860-871. [PMID: 38324746 PMCID: PMC11070137 DOI: 10.1093/hmg/ddae018] [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: 08/23/2023] [Revised: 01/02/2024] [Accepted: 01/24/2024] [Indexed: 02/09/2024] Open
Abstract
Neuromuscular disorders caused by dysfunction of the mitochondrial respiratory chain are common, severe and untreatable. We recovered a number of mitochondrial genes, including electron transport chain components, in a large forward genetic screen for mutations causing age-related neurodegeneration in the context of proteostasis dysfunction. We created a model of complex I deficiency in the Drosophila retina to probe the role of protein degradation abnormalities in mitochondrial encephalomyopathies. Using our genetic model, we found that complex I deficiency regulates both the ubiquitin/proteasome and autophagy/lysosome arms of the proteostasis machinery. We further performed an in vivo kinome screen to uncover new and potentially druggable mechanisms contributing to complex I related neurodegeneration and proteostasis failure. Reduction of RIOK kinases and the innate immune signaling kinase pelle prevented neurodegeneration in complex I deficiency animals. Genetically targeting oxidative stress, but not RIOK1 or pelle knockdown, normalized proteostasis markers. Our findings outline distinct pathways controlling neurodegeneration and protein degradation in complex I deficiency and introduce an experimentally facile model in which to study these debilitating and currently treatment-refractory disorders.
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Affiliation(s)
- Vanitha Nithianandam
- Department of Pathology, Brigham and Women’s Hospital, Harvard Medical School, 77 Avenue Louis Pasteur, Boston, MA 02115, United States
- Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, 5425 Wisconsin Avenue, Chevy Chase, MD 20815, United States
| | - Souvarish Sarkar
- Department of Pathology, Brigham and Women’s Hospital, Harvard Medical School, 77 Avenue Louis Pasteur, Boston, MA 02115, United States
- Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, 5425 Wisconsin Avenue, Chevy Chase, MD 20815, United States
| | - Mel B Feany
- Department of Pathology, Brigham and Women’s Hospital, Harvard Medical School, 77 Avenue Louis Pasteur, Boston, MA 02115, United States
- Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, 5425 Wisconsin Avenue, Chevy Chase, MD 20815, United States
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4
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Stahl A, Tomchik SM. Modeling neurodegenerative and neurodevelopmental disorders in the Drosophila mushroom body. Learn Mem 2024; 31:a053816. [PMID: 38876485 PMCID: PMC11199955 DOI: 10.1101/lm.053816.123] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Accepted: 05/01/2024] [Indexed: 06/16/2024]
Abstract
The common fruit fly Drosophila melanogaster provides a powerful platform to investigate the genetic, molecular, cellular, and neural circuit mechanisms of behavior. Research in this model system has shed light on multiple aspects of brain physiology and behavior, from fundamental neuronal function to complex behaviors. A major anatomical region that modulates complex behaviors is the mushroom body (MB). The MB integrates multimodal sensory information and is involved in behaviors ranging from sensory processing/responses to learning and memory. Many genes that underlie brain disorders are conserved, from flies to humans, and studies in Drosophila have contributed significantly to our understanding of the mechanisms of brain disorders. Genetic mutations that mimic human diseases-such as Fragile X syndrome, neurofibromatosis type 1, Parkinson's disease, and Alzheimer's disease-affect MB structure and function, altering behavior. Studies dissecting the effects of disease-causing mutations in the MB have identified key pathological mechanisms, and the development of a complete connectome promises to add a comprehensive anatomical framework for disease modeling. Here, we review Drosophila models of human neurodevelopmental and neurodegenerative disorders via the effects of their underlying mutations on MB structure, function, and the resulting behavioral alterations.
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Affiliation(s)
- Aaron Stahl
- Neuroscience and Pharmacology, University of Iowa, Iowa City, Iowa 52242, USA
| | - Seth M Tomchik
- Neuroscience and Pharmacology, University of Iowa, Iowa City, Iowa 52242, USA
- Stead Family Department of Pediatrics, University of Iowa, Iowa City, Iowa 52242, USA
- Iowa Neuroscience Institute, University of Iowa, Iowa City, Iowa 52242, USA
- Hawk-IDDRC, University of Iowa, Iowa City, Iowa 52242, USA
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5
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Petrauskas A, Fortunati DL, Kandi AR, Pothapragada SS, Agrawal K, Singh A, Huelsmeier J, Hillebrand J, Brown G, Chaturvedi D, Lee J, Lim C, Auburger G, VijayRaghavan K, Ramaswami M, Bakthavachalu B. Structured and disordered regions of Ataxin-2 contribute differently to the specificity and efficiency of mRNP granule formation. PLoS Genet 2024; 20:e1011251. [PMID: 38768217 PMCID: PMC11166328 DOI: 10.1371/journal.pgen.1011251] [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: 01/27/2024] [Revised: 06/11/2024] [Accepted: 04/05/2024] [Indexed: 05/22/2024] Open
Abstract
Ataxin-2 (ATXN2) is a gene implicated in spinocerebellar ataxia type II (SCA2), amyotrophic lateral sclerosis (ALS) and Parkinsonism. The encoded protein is a therapeutic target for ALS and related conditions. ATXN2 (or Atx2 in insects) can function in translational activation, translational repression, mRNA stability and in the assembly of mRNP-granules, a process mediated by intrinsically disordered regions (IDRs). Previous work has shown that the LSm (Like-Sm) domain of Atx2, which can help stimulate mRNA translation, antagonizes mRNP-granule assembly. Here we advance these findings through a series of experiments on Drosophila and human Ataxin-2 proteins. Results of Targets of RNA Binding Proteins Identified by Editing (TRIBE), co-localization and immunoprecipitation experiments indicate that a polyA-binding protein (PABP) interacting, PAM2 motif of Ataxin-2 may be a major determinant of the mRNA and protein content of Ataxin-2 mRNP granules. Experiments with transgenic Drosophila indicate that while the Atx2-LSm domain may protect against neurodegeneration, structured PAM2- and unstructured IDR- interactions both support Atx2-induced cytotoxicity. Taken together, the data lead to a proposal for how Ataxin-2 interactions are remodelled during translational control and how structured and non-structured interactions contribute differently to the specificity and efficiency of RNP granule condensation as well as to neurodegeneration.
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Affiliation(s)
- Arnas Petrauskas
- Trinity College Institute of Neuroscience, School of Genetics and Microbiology, Smurfit Institute of Genetics and School of Natural Sciences, Trinity College Dublin, Dublin, Ireland
| | - Daniel L. Fortunati
- Trinity College Institute of Neuroscience, School of Genetics and Microbiology, Smurfit Institute of Genetics and School of Natural Sciences, Trinity College Dublin, Dublin, Ireland
| | - Arvind Reddy Kandi
- School of Biosciences and Bioengineering, Indian Institute of Technology, Mandi, India
| | | | - Khushboo Agrawal
- Tata Institute for Genetics and Society Centre at inStem, Bellary Road, Bangalore, India
- School of Biotechnology, Amrita Vishwa Vidyapeetham University, Kollam, Kerala, India
| | - Amanjot Singh
- National Centre for Biological Sciences, TIFR, Bangalore, India
- Manipal Institute of Regenerative Medicine, MAHE-Bengaluru, Govindapura, Bengaluru, India
| | - Joern Huelsmeier
- Trinity College Institute of Neuroscience, School of Genetics and Microbiology, Smurfit Institute of Genetics and School of Natural Sciences, Trinity College Dublin, Dublin, Ireland
| | - Jens Hillebrand
- Trinity College Institute of Neuroscience, School of Genetics and Microbiology, Smurfit Institute of Genetics and School of Natural Sciences, Trinity College Dublin, Dublin, Ireland
| | - Georgia Brown
- Trinity College Institute of Neuroscience, School of Genetics and Microbiology, Smurfit Institute of Genetics and School of Natural Sciences, Trinity College Dublin, Dublin, Ireland
| | | | - Jongbo Lee
- Department of Biological Sciences, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-gil, Ulsan, Republic of Korea
| | - Chunghun Lim
- Department of Biological Sciences, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-gil, Ulsan, Republic of Korea
| | - Georg Auburger
- Experimental Neurology, Medical School, Goethe University, Frankfurt, Germany
| | | | - Mani Ramaswami
- Trinity College Institute of Neuroscience, School of Genetics and Microbiology, Smurfit Institute of Genetics and School of Natural Sciences, Trinity College Dublin, Dublin, Ireland
- National Centre for Biological Sciences, TIFR, Bangalore, India
| | - Baskar Bakthavachalu
- School of Biosciences and Bioengineering, Indian Institute of Technology, Mandi, India
- Tata Institute for Genetics and Society Centre at inStem, Bellary Road, Bangalore, India
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6
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Perlegos AE, Durkin J, Belfer SJ, Rodriguez A, Shcherbakova O, Park K, Luong J, Bonini NM, Kayser MS. TDP-43 impairs sleep in Drosophila through Ataxin-2-dependent metabolic disturbance. SCIENCE ADVANCES 2024; 10:eadj4457. [PMID: 38198547 PMCID: PMC10780954 DOI: 10.1126/sciadv.adj4457] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Accepted: 12/12/2023] [Indexed: 01/12/2024]
Abstract
Neurodegenerative diseases such as amyotrophic lateral sclerosis and frontotemporal dementia are associated with substantial sleep disruption, which may accelerate cognitive decline and brain degeneration. Here, we define a role for trans-activation response element (TAR) DNA binding protein 43 (TDP-43), a protein associated with human neurodegenerative disease, in regulating sleep using Drosophila. Expression of TDP-43 severely disrupts sleep, and the sleep deficit is rescued by Atx2 knockdown. Brain RNA sequencing revealed that Atx2 RNA interference regulates transcripts enriched for small-molecule metabolic signaling in TDP-43 brains. Focusing on these Atx2-regulated genes, we identified suppressors of the TDP-43 sleep phenotype enriched for metabolism pathways. Knockdown of Atx2 or treatment with rapamycin attenuated the sleep phenotype and mitigated the disruption of small-molecule glycogen metabolism caused by TDP-43. Our findings provide a connection between toxicity of TDP-43 and sleep disturbances and highlight key aspects of metabolism that interplay with TDP-43 toxicity upon Atx2 rescue.
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Affiliation(s)
- Alexandra E. Perlegos
- Neuroscience Graduate Group, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Biology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Jaclyn Durkin
- Department of Psychiatry, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
- National Institute of Neurological Disorders & Stroke, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Samuel J. Belfer
- Neuroscience Graduate Group, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Psychiatry, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Anyara Rodriguez
- Department of Psychiatry, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Oksana Shcherbakova
- Department of Biology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Kristen Park
- Neuroscience Graduate Group, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Jenny Luong
- Department of Psychiatry, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Nancy M. Bonini
- Neuroscience Graduate Group, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Biology, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Neuroscience, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Matthew S. Kayser
- Department of Psychiatry, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Neuroscience, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
- Chronobiology Sleep Institute, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
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7
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Dourlen P. Identification of Tau Toxicity Modifiers in the Drosophila Eye. Methods Mol Biol 2024; 2754:483-498. [PMID: 38512684 DOI: 10.1007/978-1-0716-3629-9_27] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/23/2024]
Abstract
Drosophila is a powerful model to study human diseases thanks to its genetic tools and ease of screening. Human genes can be expressed in targeted organs and their toxicity assessed on easily scorable external phenotypes that can be used as readouts to perform genetic screens of toxicity modifiers. In this chapter, I describe how to express human Tau protein in the Drosophila eye, assess protein expression by Western blot, assess Tau toxicity by quantifying the size of the Tau-induced rough eye, and perform a genetic screen of modifiers of Tau toxicity in the Drosophila eye.
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Affiliation(s)
- Pierre Dourlen
- Univ. Lille, Inserm, CHU Lille, Institut Pasteur de Lille, U1167 - RID-AGE - Facteurs de risque et déterminants moléculaires des maladies liées au vieillissement, Lille, France.
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8
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Jiang Y, MacNeil LT. Simple model systems reveal conserved mechanisms of Alzheimer's disease and related tauopathies. Mol Neurodegener 2023; 18:82. [PMID: 37950311 PMCID: PMC10638731 DOI: 10.1186/s13024-023-00664-x] [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: 04/02/2023] [Accepted: 10/04/2023] [Indexed: 11/12/2023] Open
Abstract
The lack of effective therapies that slow the progression of Alzheimer's disease (AD) and related tauopathies highlights the need for a more comprehensive understanding of the fundamental cellular mechanisms underlying these diseases. Model organisms, including yeast, worms, and flies, provide simple systems with which to investigate the mechanisms of disease. The evolutionary conservation of cellular pathways regulating proteostasis and stress response in these organisms facilitates the study of genetic factors that contribute to, or protect against, neurodegeneration. Here, we review genetic modifiers of neurodegeneration and related cellular pathways identified in the budding yeast Saccharomyces cerevisiae, the nematode Caenorhabditis elegans, and the fruit fly Drosophila melanogaster, focusing on models of AD and related tauopathies. We further address the potential of simple model systems to better understand the fundamental mechanisms that lead to AD and other neurodegenerative disorders.
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Affiliation(s)
- Yuwei Jiang
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Canada
| | - Lesley T MacNeil
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Canada.
- Farncombe Family Digestive Health Research Institute, McMaster University, Hamilton, Canada.
- Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, 1280 Main St W, Hamilton, ON, L8S 4K1, Canada.
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9
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Wu M, Li Y, Miao Y, Qiao H, Wang Y. Exploring the efficient natural products for Alzheimer's disease therapy via Drosophila melanogaster (fruit fly) models. J Drug Target 2023; 31:817-831. [PMID: 37545435 DOI: 10.1080/1061186x.2023.2245582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2023] [Revised: 07/11/2023] [Accepted: 07/31/2023] [Indexed: 08/08/2023]
Abstract
Alzheimer's disease (AD) is a grievous neurodegenerative disorder and a major form of senile dementia, which is partially caused by abnormal amyloid-beta peptide deposition and Tau protein phosphorylation. But until now, the exact pathogenesis of AD and its treatment strategy still need to investigate. Fortunately, natural products have shown potential as therapeutic agents for treating symptoms of AD due to their neuroprotective activity. To identify the excellent lead compounds for AD control from natural products of herbal medicines, as well as, detect their modes of action, suitable animal models are required. Drosophila melanogaster (fruit fly) is an important model for studying genetic and cellular biological pathways in complex biological processes. Various Drosophila AD models were broadly used for AD research, especially for the discovery of neuroprotective natural products. This review focused on the research progress of natural products in AD disease based on the fruit fly AD model, which provides a reference for using the invertebrate model in developing novel anti-AD drugs.
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Affiliation(s)
- Mengdi Wu
- School of Pharmaceutical Science and Technology, Tianjin University, Tianjin, China
| | - Ying Li
- School of Pharmaceutical Science and Technology, Tianjin University, Tianjin, China
| | - Yaodong Miao
- Second Affiliated Hospital of Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Huanhuan Qiao
- Academy of Medical Engineering and Translational Medicine, Tianjin University, Tianjin, China
| | - Yiwen Wang
- School of Pharmaceutical Science and Technology, Tianjin University, Tianjin, China
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10
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Yang M, Zinkgraf M, Fitzgerald-Cook C, Harrison BR, Putzier A, Promislow DEL, Wang AM. Using Drosophila to identify naturally occurring genetic modifiers of amyloid beta 42- and tau-induced toxicity. G3 (BETHESDA, MD.) 2023; 13:jkad132. [PMID: 37311212 PMCID: PMC10468303 DOI: 10.1093/g3journal/jkad132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Revised: 04/15/2023] [Accepted: 05/15/2023] [Indexed: 06/15/2023]
Abstract
Alzheimer's disease is characterized by 2 pathological proteins, amyloid beta 42 and tau. The majority of Alzheimer's disease cases in the population are sporadic and late-onset Alzheimer's disease, which exhibits high levels of heritability. While several genetic risk factors for late-onset Alzheimer's disease have been identified and replicated in independent studies, including the ApoE ε4 allele, the great majority of the heritability of late-onset Alzheimer's disease remains unexplained, likely due to the aggregate effects of a very large number of genes with small effect size, as well as to biases in sample collection and statistical approaches. Here, we present an unbiased forward genetic screen in Drosophila looking for naturally occurring modifiers of amyloid beta 42- and tau-induced ommatidial degeneration. Our results identify 14 significant SNPs, which map to 12 potential genes in 8 unique genomic regions. Our hits that are significant after genome-wide correction identify genes involved in neuronal development, signal transduction, and organismal development. Looking more broadly at suggestive hits (P < 10-5), we see significant enrichment in genes associated with neurogenesis, development, and growth as well as significant enrichment in genes whose orthologs have been identified as significantly or suggestively associated with Alzheimer's disease in human GWAS studies. These latter genes include ones whose orthologs are in close proximity to regions in the human genome that are associated with Alzheimer's disease, but where a causal gene has not been identified. Together, our results illustrate the potential for complementary and convergent evidence provided through multitrait GWAS in Drosophila to supplement and inform human studies, helping to identify the remaining heritability and novel modifiers of complex diseases.
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Affiliation(s)
- Ming Yang
- Department of Laboratory Medicine and Pathology, University of Washington School of Medicine, Seattle, WA 98195, USA
| | - Matthew Zinkgraf
- Department of Biology, Western Washington University, Bellingham, WA 98225, USA
| | - Cecilia Fitzgerald-Cook
- Department of Laboratory Medicine and Pathology, University of Washington School of Medicine, Seattle, WA 98195, USA
| | - Benjamin R Harrison
- Department of Laboratory Medicine and Pathology, University of Washington School of Medicine, Seattle, WA 98195, USA
| | - Alexandra Putzier
- Department of Biology, Western Washington University, Bellingham, WA 98225, USA
| | - Daniel E L Promislow
- Department of Laboratory Medicine and Pathology, University of Washington School of Medicine, Seattle, WA 98195, USA
- Department of Biology, University of Washington, Seattle, WA 98195, USA
| | - Adrienne M Wang
- Department of Biology, Western Washington University, Bellingham, WA 98225, USA
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11
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Yusuff T, Chang YC, Sang TK, Jackson GR, Chatterjee S. Codon-optimized TDP-43 mediates neurodegeneration in a Drosophila model of ALS/FTLD. Front Genet 2023; 14:881638. [PMID: 36968586 PMCID: PMC10034021 DOI: 10.3389/fgene.2023.881638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Accepted: 02/13/2023] [Indexed: 03/11/2023] Open
Abstract
Transactive response DNA binding protein-43 (TDP-43) is known to mediate neurodegeneration associated with amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD). The exact mechanism by which TDP-43 exerts toxicity in the brains, spinal cord, and lower motor neurons of affected patients remains unclear. In a novel Drosophila melanogaster model, we report gain-of-function phenotypes due to misexpression of insect codon-optimized version of human wild-type TDP-43 (CO-TDP-43) using both the binary GAL4/UAS system and direct promoter fusion constructs. The CO-TDP-43 model showed robust tissue specific phenotypes in the adult eye, wing, and bristles in the notum. Compared to non-codon optimized transgenic flies, the CO-TDP-43 flies produced increased amount of high molecular weight protein, exhibited pathogenic phenotypes, and showed cytoplasmic aggregation with both nuclear and cytoplasmic expression of TDP-43. Further characterization of the adult retina showed a disruption in the morphology and function of the photoreceptor neurons with the presence of acidic vacuoles that are characteristic of autophagy. Based on our observations, we propose that TDP-43 has the propensity to form toxic protein aggregates via a gain-of-function mechanism, and such toxic overload leads to activation of protein degradation pathways such as autophagy. The novel codon optimized TDP-43 model is an excellent resource that could be used in genetic screens to identify and better understand the exact disease mechanism of TDP-43 proteinopathies and find potential therapeutic targets.
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Affiliation(s)
- Tanzeen Yusuff
- Department of Neuroscience and Cell Biology, University of Texas Medical Branch at Galveston, Galveston, TX, United States
- Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch at Galveston, Galveston, TX, United States
- *Correspondence: Tanzeen Yusuff, ; Shreyasi Chatterjee,
| | - Ya-Chu Chang
- Department of Life Science, Institute of Biotechnology, National Tsing Hua University, Hsinchu, Taiwan
- Brain Research Center, National Tsing Hua University, Hsinchu, Taiwan
| | - Tzu-Kang Sang
- Department of Life Science, Institute of Biotechnology, National Tsing Hua University, Hsinchu, Taiwan
- Brain Research Center, National Tsing Hua University, Hsinchu, Taiwan
| | - George R. Jackson
- Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch at Galveston, Galveston, TX, United States
- Department of Neurology, University of Texas Medical Branch at Galveston, Galveston, TX, United States
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch at Galveston, Galveston, TX, United States
- Department of Neurology, Baylor College of Medicine, Houston, TX, United States
- National Parkinson’s Disease Research Education and Clinical Center, Michael E. DeBakey VA Medical Center, Houston, TX, United States
| | - Shreyasi Chatterjee
- Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch at Galveston, Galveston, TX, United States
- Department of Neurology, University of Texas Medical Branch at Galveston, Galveston, TX, United States
- Department of Biochemistry, School of Science and Technology, Nottingham Trent University, Nottingham, United Kingdom
- *Correspondence: Tanzeen Yusuff, ; Shreyasi Chatterjee,
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12
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Oliveira AC, Santos M, Pinho M, Lopes CS. String/Cdc25 phosphatase is a suppressor of Tau-associated neurodegeneration. Dis Model Mech 2023; 16:286255. [PMID: 36601903 PMCID: PMC9903143 DOI: 10.1242/dmm.049693] [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: 06/14/2022] [Accepted: 12/19/2022] [Indexed: 01/06/2023] Open
Abstract
Tau pathology is defined by the intracellular accumulation of abnormally phosphorylated Tau (MAPT) and is prevalent in several neurodegenerative disorders. The identification of modulators of Tau abnormal phosphorylation and aggregation is key to understanding disease progression and developing targeted therapeutic approaches. In this study, we identified String (Stg)/Cdc25 phosphatase as a suppressor of abnormal Tau phosphorylation and associated toxicity. Using a Drosophila model of tauopathy, we showed that Tau dephosphorylation by Stg/Cdc25 correlates with reduced Tau oligomerization, brain vacuolization and locomotor deficits in flies. Moreover, using a disease mimetic model, we provided evidence that Stg/Cdc25 reduces Tau phosphorylation levels independently of Tau aggregation status and delays neurodegeneration progression in the fly. These findings uncover a role for Stg/Cdc25 phosphatases as regulators of Tau biology that extends beyond their well-characterized function as cell-cycle regulators during cell proliferation, and indicate Stg/Cdc25-based approaches as promising entry points to target abnormal Tau phosphorylation.
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Affiliation(s)
- Andreia C. Oliveira
- Instituto de Investigação e Inovação em Saúde (i3S), Universidade do Porto, 4200-135 Porto, Portugal
- PhD Program in Molecular and Cell Biology, Instituto de Ciências Biomédicas Abel Salazar (ICBAS), Universidade do Porto, 4050-313 Porto, Portugal
- Instituto de Biologia Molecular e Celular (IBMC), Universidade do Porto, 4200-135 Porto, Portugal
| | - Madalena Santos
- Department of Anatomy, Unit for Multidisciplinary Research in Biomedicine (UMIB), ICBAS, Universidade do Porto, 4050-313 Porto, Portugal
- Laboratory for Integrative and Translational Research in Population Health (ITR), 4050-600 Porto, Portugal
- Department of Pathological, Cytological and Thanatological Anatomy, ESS|P.PORTO, 4200-072 Porto, Portugal
| | - Mafalda Pinho
- Instituto de Investigação e Inovação em Saúde (i3S), Universidade do Porto, 4200-135 Porto, Portugal
| | - Carla S. Lopes
- Instituto de Investigação e Inovação em Saúde (i3S), Universidade do Porto, 4200-135 Porto, Portugal
- Instituto de Biologia Molecular e Celular (IBMC), Universidade do Porto, 4200-135 Porto, Portugal
- Author for correspondence ()
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13
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Direct and Indirect Effects of Filamin A on Tau Pathology in Neuronal Cells. Mol Neurobiol 2023; 60:1021-1039. [PMID: 36399251 PMCID: PMC9849303 DOI: 10.1007/s12035-022-03121-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Accepted: 11/04/2022] [Indexed: 11/19/2022]
Abstract
In Alzheimer disease (AD), Tau, an axonal microtubule-associated protein, becomes hyperphosphorylated, detaches from microtubules, accumulates, and self-aggregates in the somatodendritic (SD) compartment. The accumulation of hyperphosphorylated and aggregated Tau is also seen in other neurodegenerative diseases such as frontotemporal lobar degeneration (FTLD-Tau). Previous studies reported a link between filamin A (FLNA), an actin-binding protein found in the SD compartment, and Tau pathology. In the present study, we further explored this link. We confirmed the interaction of Tau with FLNA in neuroblastoma 2a (N2a) cells. This interaction was mediated by a domain located between the 157 and 383 amino acids (a.a.) of Tau. Our results also revealed that the overexpression of FLNA resulted in an intracellular accumulation of wild-type Tau and Tau mutants (P301L, V337M, and R406W) in N2a cells. Tau phosphorylation and cleavage by caspase-3 but not its aggregation were increased upon FLNA overexpression in N2a cells. In the parietal cortex of AD brain, insoluble FLNA was increased compared to control brain, but it did not correlate with Tau pathology. Interestingly, Tau binding to microtubules and F-actin was preserved upon FLNA overexpression in N2a cells. Lastly, our results revealed that FLNA also induced the accumulation of annexin A2, a Tau interacting partner involved in its axonal localization. Collectively, our data indicated that in Tauopathies, FLNA could contribute to Tau pathology by acting on Tau and annexin A2.
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14
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Mandik F, Kanana Y, Rody J, Misera S, Wilken B, Laabs von Holt BH, Klein C, Vos M. A new model for fatty acid hydroxylase-associated neurodegeneration reveals mitochondrial and autophagy abnormalities. Front Cell Dev Biol 2022; 10:1000553. [PMID: 36589738 PMCID: PMC9794614 DOI: 10.3389/fcell.2022.1000553] [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: 07/22/2022] [Accepted: 11/22/2022] [Indexed: 12/15/2022] Open
Abstract
Fatty acid hydroxylase-associated neurodegeneration (FAHN) is a rare disease that exhibits brain modifications and motor dysfunctions in early childhood. The condition is caused by a homozygous or compound heterozygous mutation in fatty acid 2 hydroxylase (FA2H), whose encoded protein synthesizes 2-hydroxysphingolipids and 2-hydroxyglycosphingolipids and is therefore involved in sphingolipid metabolism. A few FAHN model organisms have already been established and give the first insight into symptomatic effects. However, they fail to establish the underlying cellular mechanism of FAHN so far. Drosophila is an excellent model for many neurodegenerative disorders; hence, here, we have characterized and validated the first FAHN Drosophila model. The investigation of loss of dfa2h lines revealed behavioral abnormalities, including motor impairment and flying disability, in addition to a shortened lifespan. Furthermore, alterations in mitochondrial dynamics, and autophagy were identified. Analyses of patient-derived fibroblasts, and rescue experiments with human FA2H, indicated that these defects are evolutionarily conserved. We thus present a FAHN Drosophila model organism that provides new insights into the cellular mechanism of FAHN.
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Affiliation(s)
- Frida Mandik
- Institute of Neurogenetics, University of Luebeck, UKSH, Luebeck, Germany
| | - Yuliia Kanana
- Institute of Neurogenetics, University of Luebeck, UKSH, Luebeck, Germany
| | - Jost Rody
- Institute of Neurogenetics, University of Luebeck, UKSH, Luebeck, Germany
| | - Sophie Misera
- Institute of Neurogenetics, University of Luebeck, UKSH, Luebeck, Germany
| | - Bernd Wilken
- Department of Neuropediatrics, Klinikum Kassel, Kassel, Germany
| | | | - Christine Klein
- Institute of Neurogenetics, University of Luebeck, UKSH, Luebeck, Germany
| | - Melissa Vos
- Institute of Neurogenetics, University of Luebeck, UKSH, Luebeck, Germany,*Correspondence: Melissa Vos,
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15
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Nitta Y, Sugie A. Studies of neurodegenerative diseases using Drosophila and the development of novel approaches for their analysis. Fly (Austin) 2022; 16:275-298. [PMID: 35765969 PMCID: PMC9336468 DOI: 10.1080/19336934.2022.2087484] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Revised: 05/31/2022] [Accepted: 06/03/2022] [Indexed: 02/09/2023] Open
Abstract
The use of Drosophila in neurodegenerative disease research has contributed to the identification of modifier genes for the pathology. The basis for neurodegenerative disease occurrence in Drosophila is the conservation of genes across species and the ability to perform rapid genetic analysis using a compact brain. Genetic findings previously discovered in Drosophila can reveal molecular pathologies involved in human neurological diseases in later years. Disease models using Drosophila began to be generated during the development of genetic engineering. In recent years, results of reverse translational research using Drosophila have been reported. In this review, we discuss research on neurodegenerative diseases; moreover, we introduce various methods for quantifying neurodegeneration in Drosophila.
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Affiliation(s)
- Yohei Nitta
- Brain Research Institute, Niigata University, Niigata, Japan
| | - Atsushi Sugie
- Brain Research Institute, Niigata University, Niigata, Japan
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16
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Sun ZD, Hu JX, Wu JR, Zhou B, Huang YP. Toxicities of amyloid-beta and tau protein are reciprocally enhanced in the Drosophila model. Neural Regen Res 2022; 17:2286-2292. [PMID: 35259851 PMCID: PMC9083152 DOI: 10.4103/1673-5374.336872] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Extracellular aggregation of amyloid-beta (Aβ) and intracellular tau tangles are two major pathogenic hallmarks and critical factors of Alzheimer’s disease. A linear interaction between Aβ and tau protein has been characterized in several models. Aβ induces tau hyperphosphorylation through a complex mechanism; however, the master regulators involved in this linear process are still unclear. In our study with Drosophila melanogaster, we found that Aβ regulated tau hyperphosphorylation and toxicity by activating c-Jun N-terminal kinase. Importantly, Aβ toxicity was dependent on tau hyperphosphorylation, and flies with hypophosphorylated tau were insulated against Aβ-induced toxicity. Strikingly, tau accumulation reciprocally interfered with Aβ degradation and correlated with the reduction in mRNA expression of genes encoding Aβ-degrading enzymes, including dNep1, dNep3, dMmp2, dNep4, and dIDE. Our results indicate that Aβ and tau protein work synergistically to further accelerate Alzheimer’s disease progression and may be considered as a combined target for future development of Alzheimer’s disease therapeutics.
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Affiliation(s)
- Zhen-Dong Sun
- Key Laboratory of Systems Health Science of Zhejiang Province, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, Zhejiang Province, China
| | - Jia-Xin Hu
- Key Laboratory of Systems Health Science of Zhejiang Province, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, Zhejiang Province, China
| | - Jia-Rui Wu
- Key Laboratory of Systems Health Science of Zhejiang Province, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, Zhejiang Province, China
| | - Bing Zhou
- State Key Laboratory of Membrane Biology, School of Life Sciences, Tsinghua University, Beijing, China
| | - Yun-Peng Huang
- Key Laboratory of Systems Health Science of Zhejiang Province, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, Zhejiang Province, China
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17
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Asadzadeh J, Ruchti E, Jiao W, Limoni G, MacLachlan C, Small SA, Knott G, Santa-Maria I, McCabe BD. Retromer deficiency in Tauopathy models enhances the truncation and toxicity of Tau. Nat Commun 2022; 13:5049. [PMID: 36030267 PMCID: PMC9420134 DOI: 10.1038/s41467-022-32683-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Accepted: 08/10/2022] [Indexed: 11/24/2022] Open
Abstract
Alteration of the levels, localization or post-translational processing of the microtubule associated protein Tau is associated with many neurodegenerative disorders. Here we develop adult-onset models for human Tau (hTau) toxicity in Drosophila that enable age-dependent quantitative measurement of central nervous system synapse loss and axonal degeneration, in addition to effects upon lifespan, to facilitate evaluation of factors that may contribute to Tau-dependent neurodegeneration. Using these models, we interrogate the interaction of hTau with the retromer complex, an evolutionarily conserved cargo-sorting protein assembly, whose reduced activity has been associated with both Parkinson’s and late onset Alzheimer’s disease. We reveal that reduction of retromer activity induces a potent enhancement of hTau toxicity upon synapse loss, axon retraction and lifespan through a specific increase in the production of a C-terminal truncated isoform of hTau. Our data establish a molecular and subcellular mechanism necessary and sufficient for the depletion of retromer activity to exacerbate Tau-dependent neurodegeneration. Tau and the Retromer complex are both linked to Parkinson’s and Alzheimer’s disease. Using Drosophila neurodegeneration models, this study finds that low retromer activity induces a specific increase of a highly toxic truncated form of human Tau.
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Affiliation(s)
- Jamshid Asadzadeh
- Brain Mind Institute, EPFL - Swiss Federal Institute of Technology Lausanne, Lausanne, Switzerland
| | - Evelyne Ruchti
- Brain Mind Institute, EPFL - Swiss Federal Institute of Technology Lausanne, Lausanne, Switzerland
| | - Wei Jiao
- Brain Mind Institute, EPFL - Swiss Federal Institute of Technology Lausanne, Lausanne, Switzerland
| | - Greta Limoni
- Brain Mind Institute, EPFL - Swiss Federal Institute of Technology Lausanne, Lausanne, Switzerland
| | - Catherine MacLachlan
- BioEM Facility, EPFL - Swiss Federal Institute of Technology Lausanne, Lausanne, Switzerland
| | - Scott A Small
- Department of Neurology, Columbia University, New York, USA.,Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University, New York, USA
| | - Graham Knott
- Brain Mind Institute, EPFL - Swiss Federal Institute of Technology Lausanne, Lausanne, Switzerland.,BioEM Facility, EPFL - Swiss Federal Institute of Technology Lausanne, Lausanne, Switzerland
| | - Ismael Santa-Maria
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University, New York, USA.,Department of Pathology & Cell Biology, Columbia University, New York, USA.,Facultad Ciencias Experimentales, Universidad Francisco de Vitoria, Pozuelo de Alarcón, Madrid, Spain
| | - Brian D McCabe
- Brain Mind Institute, EPFL - Swiss Federal Institute of Technology Lausanne, Lausanne, Switzerland.
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18
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Prakash P, Pradhan AK, Sheeba V. Hsp40 overexpression in pacemaker neurons delays circadian dysfunction in a Drosophila model of Huntington's disease. Dis Model Mech 2022; 15:275556. [PMID: 35645202 PMCID: PMC9254228 DOI: 10.1242/dmm.049447] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Accepted: 05/24/2022] [Indexed: 12/13/2022] Open
Abstract
Circadian disturbances are early features of neurodegenerative diseases, including Huntington's disease (HD). Emerging evidence suggests that circadian decline feeds into neurodegenerative symptoms, exacerbating them. Therefore, we asked whether known neurotoxic modifiers can suppress circadian dysfunction. We performed a screen of neurotoxicity-modifier genes to suppress circadian behavioural arrhythmicity in a Drosophila circadian HD model. The molecular chaperones Hsp40 and HSP70 emerged as significant suppressors in the circadian context, with Hsp40 being the more potent mitigator. Upon Hsp40 overexpression in the Drosophila circadian ventrolateral neurons (LNv), the behavioural rescue was associated with neuronal rescue of loss of circadian proteins from small LNv soma. Specifically, there was a restoration of the molecular clock protein Period and its oscillations in young flies and a long-lasting rescue of the output neuropeptide Pigment dispersing factor. Significantly, there was a reduction in the expanded Huntingtin inclusion load, concomitant with the appearance of a spot-like Huntingtin form. Thus, we provide evidence implicating the neuroprotective chaperone Hsp40 in circadian rehabilitation. The involvement of molecular chaperones in circadian maintenance has broader therapeutic implications for neurodegenerative diseases. This article has an associated First Person interview with the first author of the paper. Summary: This study shows, for the first time, a neuroprotective role of chaperone Hsp40 in suppressing circadian dysfunction associated with Huntington's disease in a Drosophila model.
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Affiliation(s)
- Pavitra Prakash
- Evolutionary and Integrative Biology Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore 560064, India
| | - Arpit Kumar Pradhan
- Neuroscience Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore 560064, India
| | - Vasu Sheeba
- Evolutionary and Integrative Biology Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore 560064, India.,Neuroscience Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore 560064, India
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19
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Prifti E, Tsakiri EN, Vourkou E, Stamatakis G, Samiotaki M, Skoulakis EMC, Papanikolopoulou K. Mical modulates Tau toxicity via cysteine oxidation in vivo. Acta Neuropathol Commun 2022; 10:44. [PMID: 35379354 PMCID: PMC8981811 DOI: 10.1186/s40478-022-01348-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Accepted: 03/18/2022] [Indexed: 12/24/2022] Open
Abstract
Tau accumulation is clearly linked to pathogenesis in Alzheimer’s disease and other Tauopathies. However, processes leading to Tau fibrillization and reasons for its pathogenicity remain largely elusive. Mical emerged as a novel interacting protein of human Tau expressed in Drosophila brains. Mical is characterized by the presence of a flavoprotein monooxygenase domain that generates redox potential with which it can oxidize target proteins. In the well-established Drosophila Tauopathy model, we use genetic interactions to show that Mical alters Tau interactions with microtubules and the Actin cytoskeleton and greatly affects Tau aggregation propensity and Tau-associated toxicity and dysfunction. Exploration of the mechanism was pursued using a Mical inhibitor, a mutation in Mical that selectively disrupts its monooxygenase domain, Tau transgenes mutated at cysteine residues targeted by Mical and mass spectrometry analysis to quantify cysteine oxidation. The collective evidence strongly indicates that Mical’s redox activity mediates the effects on Tau via oxidation of Cys322. Importantly, we also validate results from the fly model in human Tauopathy samples by showing that MICAL1 is up-regulated in patient brains and co-localizes with Tau in Pick bodies. Our work provides mechanistic insights into the role of the Tau cysteine residues as redox-switches regulating the process of Tau self-assembly into inclusions in vivo, its function as a cytoskeletal protein and its effect on neuronal toxicity and dysfunction.
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20
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Giong HK, Subramanian M, Yu K, Lee JS. Non-Rodent Genetic Animal Models for Studying Tauopathy: Review of Drosophila, Zebrafish, and C. elegans Models. Int J Mol Sci 2021; 22:8465. [PMID: 34445171 PMCID: PMC8395099 DOI: 10.3390/ijms22168465] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 08/03/2021] [Accepted: 08/04/2021] [Indexed: 12/12/2022] Open
Abstract
Tauopathy refers to a group of progressive neurodegenerative diseases, including frontotemporal lobar degeneration and Alzheimer's disease, which correlate with the malfunction of microtubule-associated protein Tau (MAPT) due to abnormal hyperphosphorylation, leading to the formation of intracellular aggregates in the brain. Despite extensive efforts to understand tauopathy and develop an efficient therapy, our knowledge is still far from complete. To find a solution for this group of devastating diseases, several animal models that mimic diverse disease phenotypes of tauopathy have been developed. Rodents are the dominating tauopathy models because of their similarity to humans and established disease lines, as well as experimental approaches. However, powerful genetic animal models using Drosophila, zebrafish, and C. elegans have also been developed for modeling tauopathy and have contributed to understanding the pathophysiology of tauopathy. The success of these models stems from the short lifespans, versatile genetic tools, real-time in-vivo imaging, low maintenance costs, and the capability for high-throughput screening. In this review, we summarize the main findings on mechanisms of tauopathy and discuss the current tauopathy models of these non-rodent genetic animals, highlighting their key advantages and limitations in tauopathy research.
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Affiliation(s)
- Hoi-Khoanh Giong
- Disease Target Structure Research Center, KRIBB, 125 Gwahak-ro, Yuseong-gu, Daejeon 34141, Korea; (H.-K.G.); (M.S.)
- KRIBB School, University of Science and Technology, 125 Gwahak-ro, Yuseong-gu, Daejeon 34141, Korea
- Dementia DTC R&D Convergence Program, KIST, Hwarang-ro 14 gil 5, Seongbuk-gu, Seoul 02792, Korea
| | - Manivannan Subramanian
- Disease Target Structure Research Center, KRIBB, 125 Gwahak-ro, Yuseong-gu, Daejeon 34141, Korea; (H.-K.G.); (M.S.)
- Dementia DTC R&D Convergence Program, KIST, Hwarang-ro 14 gil 5, Seongbuk-gu, Seoul 02792, Korea
| | - Kweon Yu
- Disease Target Structure Research Center, KRIBB, 125 Gwahak-ro, Yuseong-gu, Daejeon 34141, Korea; (H.-K.G.); (M.S.)
- KRIBB School, University of Science and Technology, 125 Gwahak-ro, Yuseong-gu, Daejeon 34141, Korea
- Dementia DTC R&D Convergence Program, KIST, Hwarang-ro 14 gil 5, Seongbuk-gu, Seoul 02792, Korea
| | - Jeong-Soo Lee
- Disease Target Structure Research Center, KRIBB, 125 Gwahak-ro, Yuseong-gu, Daejeon 34141, Korea; (H.-K.G.); (M.S.)
- KRIBB School, University of Science and Technology, 125 Gwahak-ro, Yuseong-gu, Daejeon 34141, Korea
- Dementia DTC R&D Convergence Program, KIST, Hwarang-ro 14 gil 5, Seongbuk-gu, Seoul 02792, Korea
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21
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Subramanian M, Hyeon SJ, Das T, Suh YS, Kim YK, Lee JS, Song EJ, Ryu H, Yu K. UBE4B, a microRNA-9 target gene, promotes autophagy-mediated Tau degradation. Nat Commun 2021; 12:3291. [PMID: 34078905 PMCID: PMC8172564 DOI: 10.1038/s41467-021-23597-9] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Accepted: 04/29/2021] [Indexed: 02/07/2023] Open
Abstract
The formation of hyperphosphorylated intracellular Tau tangles in the brain is a hallmark of Alzheimer's disease (AD). Tau hyperphosphorylation destabilizes microtubules, promoting neurodegeneration in AD patients. To identify suppressors of tau-mediated AD, we perform a screen using a microRNA (miR) library in Drosophila and identify the miR-9 family as suppressors of human tau overexpression phenotypes. CG11070, a miR-9a target gene, and its mammalian orthologue UBE4B, an E3/E4 ubiquitin ligase, alleviate eye neurodegeneration, synaptic bouton defects, and crawling phenotypes in Drosophila human tau overexpression models. Total and phosphorylated Tau levels also decrease upon CG11070 or UBE4B overexpression. In mammalian neuroblastoma cells, overexpression of UBE4B and STUB1, which encodes the E3 ligase CHIP, increases the ubiquitination and degradation of Tau. In the Tau-BiFC mouse model, UBE4B and STUB1 overexpression also increase oligomeric Tau degradation. Inhibitor assays of the autophagy and proteasome systems reveal that the autophagy-lysosome system is the major pathway for Tau degradation in this context. These results demonstrate that UBE4B, a miR-9 target gene, promotes autophagy-mediated Tau degradation together with STUB1, and is thus an innovative therapeutic approach for AD.
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Affiliation(s)
- Manivannan Subramanian
- grid.249967.70000 0004 0636 3099Metabolism and Neurophysiology Research Group, KRIBB, Daejeon, Korea ,grid.511114.1Convergence Research Center of Dementia, KIST, Seoul, Korea
| | - Seung Jae Hyeon
- grid.35541.360000000121053345Center for Neuroscience, Brain Science Institute, KIST, Seoul, Korea
| | - Tanuza Das
- grid.35541.360000000121053345Biomedical Research Institute, KIST, Seoul, Korea
| | - Yoon Seok Suh
- grid.249967.70000 0004 0636 3099Metabolism and Neurophysiology Research Group, KRIBB, Daejeon, Korea
| | - Yun Kyung Kim
- grid.511114.1Convergence Research Center of Dementia, KIST, Seoul, Korea
| | - Jeong-Soo Lee
- grid.249967.70000 0004 0636 3099Metabolism and Neurophysiology Research Group, KRIBB, Daejeon, Korea ,grid.511114.1Convergence Research Center of Dementia, KIST, Seoul, Korea
| | - Eun Joo Song
- grid.255649.90000 0001 2171 7754Graduate School of Pharmaceutical Sciences and College of Pharmacy, Ewha Womans University, Seoul, Korea
| | - Hoon Ryu
- grid.35541.360000000121053345Center for Neuroscience, Brain Science Institute, KIST, Seoul, Korea
| | - Kweon Yu
- grid.249967.70000 0004 0636 3099Metabolism and Neurophysiology Research Group, KRIBB, Daejeon, Korea ,grid.511114.1Convergence Research Center of Dementia, KIST, Seoul, Korea ,grid.412786.e0000 0004 1791 8264Department of Functional Genomics, UST, Daejeon, Korea
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22
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Nangia V, O'Connell J, Chopra K, Qing Y, Reppert C, Chai CM, Bhasiin K, Colodner KJ. Genetic reduction of tyramine β hydroxylase suppresses Tau toxicity in a Drosophila model of tauopathy. Neurosci Lett 2021; 755:135937. [PMID: 33910059 DOI: 10.1016/j.neulet.2021.135937] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 04/23/2021] [Accepted: 04/23/2021] [Indexed: 01/21/2023]
Abstract
Tauopathies are a class of neurodegenerative diseases characterized by the abnormal phosphorylation and accumulation of the microtubule-associated protein, Tau. These diseases are associated with degeneration and dysfunction of the noradrenergic system, a critical regulator of memory, locomotion, and the fight or flight response. Though Tau pathology accumulates early in noradrenergic neurons, the relationship between noradrenaline signaling and tauopathy pathogenesis remains unclear. The fruit fly, Drosophila melanogaster, is a valuable model organism commonly used to investigate factors that promote Tau-mediated degeneration. Moreover, Drosophila contain the biogenic amine, octopamine, which is the functional homolog to noradrenaline. Using a Drosophila model of tauopathy, we conducted a candidate modifier screen targeting tyramine β hydroxylase (tβh), the enzyme that controls the production of octopamine in the fly, to determine if levels of this enzyme modulate Tau-induced degeneration in the fly eye. We found that genetic reduction of tβh suppresses Tau toxicity, independent of Tau phosphorylation. These findings show that reduction of tβh, a critical enzyme in the octopaminergic pathway, suppresses Tau pathogenicity and establishes an interaction that can be further utilized to determine the relationship between noradrenergic-like signaling and Tau toxicity in Drosophila.
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Affiliation(s)
- Varuna Nangia
- Program in Neuroscience & Behavior, Mount Holyoke College, South Hadley, MA, USA
| | - Julia O'Connell
- Program in Neuroscience & Behavior, Mount Holyoke College, South Hadley, MA, USA
| | - Kusha Chopra
- Program in Neuroscience & Behavior, Mount Holyoke College, South Hadley, MA, USA
| | - Yaling Qing
- Program in Neuroscience & Behavior, Mount Holyoke College, South Hadley, MA, USA
| | - Camille Reppert
- Program in Neuroscience & Behavior, Mount Holyoke College, South Hadley, MA, USA
| | - Cynthia M Chai
- Program in Neuroscience & Behavior, Mount Holyoke College, South Hadley, MA, USA
| | - Kesshni Bhasiin
- Program in Neuroscience & Behavior, Mount Holyoke College, South Hadley, MA, USA
| | - Kenneth J Colodner
- Program in Neuroscience & Behavior, Mount Holyoke College, South Hadley, MA, USA.
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23
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Canet-Pons J, Sen NE, Arsović A, Almaguer-Mederos LE, Halbach MV, Key J, Döring C, Kerksiek A, Picchiarelli G, Cassel R, René F, Dieterlé S, Fuchs NV, König R, Dupuis L, Lütjohann D, Gispert S, Auburger G. Atxn2-CAG100-KnockIn mouse spinal cord shows progressive TDP43 pathology associated with cholesterol biosynthesis suppression. Neurobiol Dis 2021; 152:105289. [PMID: 33577922 DOI: 10.1016/j.nbd.2021.105289] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 12/11/2020] [Accepted: 02/03/2021] [Indexed: 12/12/2022] Open
Abstract
Large polyglutamine expansions in Ataxin-2 (ATXN2) cause multi-system nervous atrophy in Spinocerebellar Ataxia type 2 (SCA2). Intermediate size expansions carry a risk for selective motor neuron degeneration, known as Amyotrophic Lateral Sclerosis (ALS). Conversely, the depletion of ATXN2 prevents disease progression in ALS. Although ATXN2 interacts directly with RNA, and in ALS pathogenesis there is a crucial role of RNA toxicity, the affected functional pathways remain ill defined. Here, we examined an authentic SCA2 mouse model with Atxn2-CAG100-KnockIn for a first definition of molecular mechanisms in spinal cord pathology. Neurophysiology of lower limbs detected sensory neuropathy rather than motor denervation. Triple immunofluorescence demonstrated cytosolic ATXN2 aggregates sequestrating TDP43 and TIA1 from the nucleus. In immunoblots, this was accompanied by elevated CASP3, RIPK1 and PQBP1 abundance. RT-qPCR showed increase of Grn, Tlr7 and Rnaset2 mRNA versus Eif5a2, Dcp2, Uhmk1 and Kif5a decrease. These SCA2 findings overlap well with known ALS features. Similar to other ataxias and dystonias, decreased mRNA levels for Unc80, Tacr1, Gnal, Ano3, Kcna2, Elovl5 and Cdr1 contrasted with Gpnmb increase. Preterminal stage tissue showed strongly activated microglia containing ATXN2 aggregates, with parallel astrogliosis. Global transcriptome profiles from stages of incipient motor deficit versus preterminal age identified molecules with progressive downregulation, where a cluster of cholesterol biosynthesis enzymes including Dhcr24, Msmo1, Idi1 and Hmgcs1 was prominent. Gas chromatography demonstrated a massive loss of crucial cholesterol precursor metabolites. Overall, the ATXN2 protein aggregation process affects diverse subcellular compartments, in particular stress granules, endoplasmic reticulum and receptor tyrosine kinase signaling. These findings identify new targets and potential biomarkers for neuroprotective therapies.
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Affiliation(s)
- Júlia Canet-Pons
- Experimental Neurology, Medical Faculty, Goethe University, 60590 Frankfurt am Main, Germany
| | - Nesli-Ece Sen
- Experimental Neurology, Medical Faculty, Goethe University, 60590 Frankfurt am Main, Germany; Faculty of Biosciences, Goethe University, 60438 Frankfurt am Main, Germany
| | - Aleksandar Arsović
- Experimental Neurology, Medical Faculty, Goethe University, 60590 Frankfurt am Main, Germany
| | - Luis-Enrique Almaguer-Mederos
- Experimental Neurology, Medical Faculty, Goethe University, 60590 Frankfurt am Main, Germany; Center for Investigation and Rehabilitation of Hereditary Ataxias (CIRAH), Holguín, Cuba
| | - Melanie V Halbach
- Experimental Neurology, Medical Faculty, Goethe University, 60590 Frankfurt am Main, Germany
| | - Jana Key
- Experimental Neurology, Medical Faculty, Goethe University, 60590 Frankfurt am Main, Germany; Faculty of Biosciences, Goethe University, 60438 Frankfurt am Main, Germany
| | - Claudia Döring
- Dr. Senckenberg Institute of Pathology, Medical Faculty, Goethe University, 60590 Frankfurt am Main, Germany
| | - Anja Kerksiek
- Institute of Clinical Chemistry and Clinical Pharmacology, University Hospital Bonn, 53127 Bonn, Nordrhein-Westfalen, Germany
| | - Gina Picchiarelli
- UMRS-1118 INSERM, Faculty of Medicine, University of Strasbourg, 67000 Strasbourg, France
| | - Raphaelle Cassel
- UMRS-1118 INSERM, Faculty of Medicine, University of Strasbourg, 67000 Strasbourg, France
| | - Frédérique René
- UMRS-1118 INSERM, Faculty of Medicine, University of Strasbourg, 67000 Strasbourg, France
| | - Stéphane Dieterlé
- UMRS-1118 INSERM, Faculty of Medicine, University of Strasbourg, 67000 Strasbourg, France
| | - Nina V Fuchs
- Host-Pathogen Interactions, Paul-Ehrlich-Institute, 63225 Langen, Germany
| | - Renate König
- Host-Pathogen Interactions, Paul-Ehrlich-Institute, 63225 Langen, Germany
| | - Luc Dupuis
- UMRS-1118 INSERM, Faculty of Medicine, University of Strasbourg, 67000 Strasbourg, France
| | - Dieter Lütjohann
- Institute of Clinical Chemistry and Clinical Pharmacology, University Hospital Bonn, 53127 Bonn, Nordrhein-Westfalen, Germany
| | - Suzana Gispert
- Experimental Neurology, Medical Faculty, Goethe University, 60590 Frankfurt am Main, Germany
| | - Georg Auburger
- Experimental Neurology, Medical Faculty, Goethe University, 60590 Frankfurt am Main, Germany.
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24
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Mangleburg CG, Wu T, Yalamanchili HK, Guo C, Hsieh YC, Duong DM, Dammer EB, De Jager PL, Seyfried NT, Liu Z, Shulman JM. Integrated analysis of the aging brain transcriptome and proteome in tauopathy. Mol Neurodegener 2020; 15:56. [PMID: 32993812 PMCID: PMC7526226 DOI: 10.1186/s13024-020-00405-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Accepted: 09/18/2020] [Indexed: 01/09/2023] Open
Abstract
Background Tau neurofibrillary tangle pathology characterizes Alzheimer’s disease and other neurodegenerative tauopathies. Brain gene expression profiles can reveal mechanisms; however, few studies have systematically examined both the transcriptome and proteome or differentiated Tau- versus age-dependent changes. Methods Paired, longitudinal RNA-sequencing and mass-spectrometry were performed in a Drosophila model of tauopathy, based on pan-neuronal expression of human wildtype Tau (TauWT) or a mutant form causing frontotemporal dementia (TauR406W). Tau-induced, differentially expressed transcripts and proteins were examined cross-sectionally or using linear regression and adjusting for age. Hierarchical clustering was performed to highlight network perturbations, and we examined overlaps with human brain gene expression profiles in tauopathy. Results TauWT induced 1514 and 213 differentially expressed transcripts and proteins, respectively. TauR406W had a substantially greater impact, causing changes in 5494 transcripts and 697 proteins. There was a ~ 70% overlap between age- and Tau-induced changes and our analyses reveal pervasive bi-directional interactions. Strikingly, 42% of Tau-induced transcripts were discordant in the proteome, showing opposite direction of change. Tau-responsive gene expression networks strongly implicate innate immune activation. Cross-species analyses pinpoint human brain gene perturbations specifically triggered by Tau pathology and/or aging, and further differentiate between disease amplifying and protective changes. Conclusions Our results comprise a powerful, cross-species functional genomics resource for tauopathy, revealing Tau-mediated disruption of gene expression, including dynamic, age-dependent interactions between the brain transcriptome and proteome.
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Affiliation(s)
- Carl Grant Mangleburg
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030, USA.,Medical Scientist Training Program, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Timothy Wu
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030, USA.,Medical Scientist Training Program, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Hari K Yalamanchili
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Caiwei Guo
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Yi-Chen Hsieh
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Duc M Duong
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Eric B Dammer
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Philip L De Jager
- Center for Translational & Computational Neuroimmunology, Department of Neurology and Taub Institute for the study of Alzheimer's disease and the aging brain, Columbia University Medical Center, New York, NY, 10032, USA.,Cell Circuits Program, Broad Institute, Cambridge, MA, 02142, USA
| | - Nicholas T Seyfried
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, 30322, USA.,Department of Neurology, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Zhandong Liu
- Department of Pediatrics, Baylor College of Medicine, Houston, TX, 77030, USA.,Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, 1250 Moursund St., Suite N.1150, Houston, TX, 77030, USA
| | - Joshua M Shulman
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030, USA. .,Department of Neuroscience, Baylor College of Medicine, Houston, TX, 77030, USA. .,Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, 1250 Moursund St., Suite N.1150, Houston, TX, 77030, USA. .,Department of Neurology, Baylor College of Medicine, Houston, TX, 77030, USA.
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25
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Biophysical studies of protein misfolding and aggregation in in vivo models of Alzheimer's and Parkinson's diseases. Q Rev Biophys 2020; 49:e22. [PMID: 32493529 DOI: 10.1017/s0033583520000025] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Neurodegenerative disorders, including Alzheimer's (AD) and Parkinson's diseases (PD), are characterised by the formation of aberrant assemblies of misfolded proteins. The discovery of disease-modifying drugs for these disorders is challenging, in part because we still have a limited understanding of their molecular origins. In this review, we discuss how biophysical approaches can help explain the formation of the aberrant conformational states of proteins whose neurotoxic effects underlie these diseases. We discuss in particular models based on the transgenic expression of amyloid-β (Aβ) and tau in AD, and α-synuclein in PD. Because biophysical methods have enabled an accurate quantification and a detailed understanding of the molecular mechanisms underlying protein misfolding and aggregation in vitro, we expect that the further development of these methods to probe directly the corresponding mechanisms in vivo will open effective routes for diagnostic and therapeutic interventions.
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26
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Lam I, Hallacli E, Khurana V. Proteome-Scale Mapping of Perturbed Proteostasis in Living Cells. Cold Spring Harb Perspect Biol 2020; 12:cshperspect.a034124. [PMID: 30910772 DOI: 10.1101/cshperspect.a034124] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Proteinopathies are degenerative diseases in which specific proteins adopt deleterious conformations, leading to the dysfunction and demise of distinct cell types. They comprise some of the most significant diseases of aging-from Alzheimer's disease to Parkinson's disease to type 2 diabetes-for which not a single disease-modifying or preventative strategy exists. Here, we survey approaches in tractable cellular and organismal models that bring us toward a more complete understanding of the molecular consequences of protein misfolding. These include proteome-scale profiling of genetic modifiers, as well as transcriptional and proteome changes. We describe assays that can capture protein interactomes in situ and distinct protein conformational states. A picture of cellular drivers and responders to proteotoxicity emerges from this work, distinguishing general alterations of proteostasis from cellular events that are deeply tied to the intrinsic function of the misfolding protein. These distinctions have consequences for the understanding and treatment of proteinopathies.
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Affiliation(s)
- Isabel Lam
- Ann Romney Center for Neurologic Disease, Department of Neurology, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115
| | - Erinc Hallacli
- Ann Romney Center for Neurologic Disease, Department of Neurology, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115
| | - Vikram Khurana
- Ann Romney Center for Neurologic Disease, Department of Neurology, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115.,Broad Institute of MIT and Harvard, Cambridge, Massachusetts 02142.,Harvard Stem Cell Institute, Cambridge, Massachusetts 02138.,New York Stem Cell Foundation - Robertson Investigator
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27
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Genetic Dissection of Alzheimer's Disease Using Drosophila Models. Int J Mol Sci 2020; 21:ijms21030884. [PMID: 32019113 PMCID: PMC7037931 DOI: 10.3390/ijms21030884] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 01/26/2020] [Accepted: 01/26/2020] [Indexed: 02/06/2023] Open
Abstract
Alzheimer’s disease (AD), a main cause of dementia, is the most common neurodegenerative disease that is related to abnormal accumulation of the amyloid β (Aβ) protein. Despite decades of intensive research, the mechanisms underlying AD remain elusive, and the only available treatment remains symptomatic. Molecular understanding of the pathogenesis and progression of AD is necessary to develop disease-modifying treatment. Drosophila, as the most advanced genetic model, has been used to explore the molecular mechanisms of AD in the last few decades. Here, we introduce Drosophila AD models based on human Aβ and summarize the results of their genetic dissection. We also discuss the utility of functional genomics using the Drosophila system in the search for AD-associated molecular mechanisms in the post-genomic era.
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28
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Sen NE, Arsovic A, Meierhofer D, Brodesser S, Oberschmidt C, Canet-Pons J, Kaya ZE, Halbach MV, Gispert S, Sandhoff K, Auburger G. In Human and Mouse Spino-Cerebellar Tissue, Ataxin-2 Expansion Affects Ceramide-Sphingomyelin Metabolism. Int J Mol Sci 2019; 20:E5854. [PMID: 31766565 PMCID: PMC6928749 DOI: 10.3390/ijms20235854] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Revised: 11/19/2019] [Accepted: 11/20/2019] [Indexed: 02/08/2023] Open
Abstract
Ataxin-2 (human gene symbol ATXN2) acts during stress responses, modulating mRNA translation and nutrient metabolism. Ataxin-2 knockout mice exhibit progressive obesity, dyslipidemia, and insulin resistance. Conversely, the progressive ATXN2 gain of function due to the fact of polyglutamine (polyQ) expansions leads to a dominantly inherited neurodegenerative process named spinocerebellar ataxia type 2 (SCA2) with early adipose tissue loss and late muscle atrophy. We tried to understand lipid dysregulation in a SCA2 patient brain and in an authentic mouse model. Thin layer chromatography of a patient cerebellum was compared to the lipid metabolome of Atxn2-CAG100-Knockin (KIN) mouse spinocerebellar tissue. The human pathology caused deficits of sulfatide, galactosylceramide, cholesterol, C22/24-sphingomyelin, and gangliosides GM1a/GD1b despite quite normal levels of C18-sphingomyelin. Cerebellum and spinal cord from the KIN mouse showed a consistent decrease of various ceramides with a significant elevation of sphingosine in the more severely affected spinal cord. Deficiency of C24/26-sphingomyelins contrasted with excess C18/20-sphingomyelin. Spinocerebellar expression profiling revealed consistent reductions of CERS protein isoforms, Sptlc2 and Smpd3, but upregulation of Cers2 mRNA, as prominent anomalies in the ceramide-sphingosine metabolism. Reduction of Asah2 mRNA correlated to deficient S1P levels. In addition, downregulations for the elongase Elovl1, Elovl4, Elovl5 mRNAs and ELOVL4 protein explain the deficit of very long-chain sphingomyelin. Reduced ASMase protein levels correlated to the accumulation of long-chain sphingomyelin. Overall, a deficit of myelin lipids was prominent in SCA2 nervous tissue at prefinal stage and not compensated by transcriptional adaptation of several metabolic enzymes. Myelination is controlled by mTORC1 signals; thus, our human and murine observations are in agreement with the known role of ATXN2 yeast, nematode, and mouse orthologs as mTORC1 inhibitors and autophagy promoters.
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Affiliation(s)
- Nesli-Ece Sen
- Experimental Neurology, Building 89, Goethe University Medical Faculty, Theodor Stern Kai 7, 60590 Frankfurt am Main, Germany; (N.-E.S.); (A.A.); (C.O.); (J.C.-P.); (Z.-E.K.); (M.-V.H.); (S.G.)
- Faculty of Biosciences, Goethe-University, 60438 Frankfurt am Main, Germany
| | - Aleksandar Arsovic
- Experimental Neurology, Building 89, Goethe University Medical Faculty, Theodor Stern Kai 7, 60590 Frankfurt am Main, Germany; (N.-E.S.); (A.A.); (C.O.); (J.C.-P.); (Z.-E.K.); (M.-V.H.); (S.G.)
| | - David Meierhofer
- Max Planck Institute for Molecular Genetics, Ihnestrasse 63-73, 14195 Berlin, Germany;
| | - Susanne Brodesser
- Membrane Biology and Lipid Biochemistry Unit, Life and Medical Sciences Institute, University of Bonn, 53121 Bonn, Germany;
| | - Carola Oberschmidt
- Experimental Neurology, Building 89, Goethe University Medical Faculty, Theodor Stern Kai 7, 60590 Frankfurt am Main, Germany; (N.-E.S.); (A.A.); (C.O.); (J.C.-P.); (Z.-E.K.); (M.-V.H.); (S.G.)
| | - Júlia Canet-Pons
- Experimental Neurology, Building 89, Goethe University Medical Faculty, Theodor Stern Kai 7, 60590 Frankfurt am Main, Germany; (N.-E.S.); (A.A.); (C.O.); (J.C.-P.); (Z.-E.K.); (M.-V.H.); (S.G.)
| | - Zeynep-Ece Kaya
- Experimental Neurology, Building 89, Goethe University Medical Faculty, Theodor Stern Kai 7, 60590 Frankfurt am Main, Germany; (N.-E.S.); (A.A.); (C.O.); (J.C.-P.); (Z.-E.K.); (M.-V.H.); (S.G.)
- Cerrahpasa School of Medicine, Istanbul University, 34098 Istanbul, Turkey
| | - Melanie-Vanessa Halbach
- Experimental Neurology, Building 89, Goethe University Medical Faculty, Theodor Stern Kai 7, 60590 Frankfurt am Main, Germany; (N.-E.S.); (A.A.); (C.O.); (J.C.-P.); (Z.-E.K.); (M.-V.H.); (S.G.)
| | - Suzana Gispert
- Experimental Neurology, Building 89, Goethe University Medical Faculty, Theodor Stern Kai 7, 60590 Frankfurt am Main, Germany; (N.-E.S.); (A.A.); (C.O.); (J.C.-P.); (Z.-E.K.); (M.-V.H.); (S.G.)
| | - Konrad Sandhoff
- Membrane Biology and Lipid Biochemistry Unit, Life and Medical Sciences Institute, University of Bonn, 53121 Bonn, Germany;
| | - Georg Auburger
- Experimental Neurology, Building 89, Goethe University Medical Faculty, Theodor Stern Kai 7, 60590 Frankfurt am Main, Germany; (N.-E.S.); (A.A.); (C.O.); (J.C.-P.); (Z.-E.K.); (M.-V.H.); (S.G.)
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29
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Hsieh YC, Guo C, Yalamanchili HK, Abreha M, Al-Ouran R, Li Y, Dammer EB, Lah JJ, Levey AI, Bennett DA, De Jager PL, Seyfried NT, Liu Z, Shulman JM. Tau-Mediated Disruption of the Spliceosome Triggers Cryptic RNA Splicing and Neurodegeneration in Alzheimer's Disease. Cell Rep 2019; 29:301-316.e10. [PMID: 31597093 PMCID: PMC6919331 DOI: 10.1016/j.celrep.2019.08.104] [Citation(s) in RCA: 101] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2019] [Revised: 06/29/2019] [Accepted: 08/29/2019] [Indexed: 12/12/2022] Open
Abstract
In Alzheimer's disease (AD), spliceosomal proteins with critical roles in RNA processing aberrantly aggregate and mislocalize to Tau neurofibrillary tangles. We test the hypothesis that Tau-spliceosome interactions disrupt pre-mRNA splicing in AD. In human postmortem brain with AD pathology, Tau coimmunoprecipitates with spliceosomal components. In Drosophila, pan-neuronal Tau expression triggers reductions in multiple core and U1-specific spliceosomal proteins, and genetic disruption of these factors, including SmB, U1-70K, and U1A, enhances Tau-mediated neurodegeneration. We further show that loss of function in SmB, encoding a core spliceosomal protein, causes decreased survival, progressive locomotor impairment, and neuronal loss, independent of Tau toxicity. Lastly, RNA sequencing reveals a similar profile of mRNA splicing errors in SmB mutant and Tau transgenic flies, including intron retention and non-annotated cryptic splice junctions. In human brains, we confirm cryptic splicing errors in association with neurofibrillary tangle burden. Our results implicate spliceosome disruption and the resulting transcriptome perturbation in Tau-mediated neurodegeneration in AD.
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Affiliation(s)
- Yi-Chen Hsieh
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Caiwei Guo
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA
| | - Hari K Yalamanchili
- Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Measho Abreha
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Rami Al-Ouran
- Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Yarong Li
- Department of Neurology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Eric B Dammer
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - James J Lah
- Department of Neurology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Allan I Levey
- Department of Neurology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - David A Bennett
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL 60612, USA
| | - Philip L De Jager
- Center for Translational and Computational Neuroimmunology, Department of Neurology, Columbia University Medical Center, New York, NY 10032, USA; Cell Circuits Program, Broad Institute, Cambridge, MA 02142, USA
| | - Nicholas T Seyfried
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322, USA; Department of Neurology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Zhandong Liu
- Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA
| | - Joshua M Shulman
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA; Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA; Department of Neurology, Baylor College of Medicine, Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA.
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30
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Shim KH, Kim SH, Hur J, Kim DH, Demirev AV, Yoon SY. Small-molecule drug screening identifies drug Ro 31-8220 that reduces toxic phosphorylated tau in Drosophila melanogaster. Neurobiol Dis 2019; 130:104519. [DOI: 10.1016/j.nbd.2019.104519] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Revised: 05/13/2019] [Accepted: 06/20/2019] [Indexed: 12/16/2022] Open
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31
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Drosophila Tau Negatively Regulates Translation and Olfactory Long-Term Memory, But Facilitates Footshock Habituation and Cytoskeletal Homeostasis. J Neurosci 2019; 39:8315-8329. [PMID: 31488613 DOI: 10.1523/jneurosci.0391-19.2019] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Revised: 07/24/2019] [Accepted: 08/07/2019] [Indexed: 01/07/2023] Open
Abstract
Although the involvement of pathological tau in neurodegenerative dementias is indisputable, its physiological roles have remained elusive in part because its abrogation has been reported without overt phenotypes in mice and Drosophila This was addressed using the recently described Drosophila tauKO and Mi{MIC} mutants and focused on molecular and behavioral analyses. Initially, we show that Drosophila tau (dTau) loss precipitates dynamic cytoskeletal changes in the adult Drosophila CNS and translation upregulation. Significantly, we demonstrate for the first time distinct roles for dTau in adult mushroom body (MB)-dependent neuroplasticity as its downregulation within α'β'neurons impairs habituation. In accord with its negative regulation of translation, dTau loss specifically enhances protein synthesis-dependent long-term memory (PSD-LTM), but not anesthesia-resistant memory. In contrast, elevation of the protein in the MBs yielded premature habituation and depressed PSD-LTM. Therefore, tau loss in Drosophila dynamically alters brain cytoskeletal dynamics and profoundly affects neuronal proteostasis and plasticity.SIGNIFICANCE STATEMENT We demonstrate that despite modest sequence divergence, the Drosophila tau (dTau) is a true vertebrate tau ortholog as it interacts with the neuronal microtubule and actin cytoskeleton. Novel physiological roles for dTau in regulation of translation, long-term memory, and footshock habituation are also revealed. These emerging insights on tau physiological functions are invaluable for understanding the molecular pathways and processes perturbed in tauopathies.
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32
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Papanikolopoulou K, Mudher A, Skoulakis E. An assessment of the translational relevance of Drosophila in drug discovery. Expert Opin Drug Discov 2019; 14:303-313. [PMID: 30664368 DOI: 10.1080/17460441.2019.1569624] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
INTRODUCTION Drosophila melanogaster offers a powerful expedient and economical system with facile genetics. Because of the high sequence and functional conservation with human disease-associated genes, it has been cardinal in deciphering disease mechanisms at the genetic and molecular level. Drosophila are amenable to and respond well to pharmaceutical treatment which coupled to their genetic tractability has led to discovery, repositioning, and validation of a number of compounds. Areas covered: This review summarizes the generation of fly models of human diseases, their advantages and use in elucidation of human disease mechanisms. Representative studies provide examples of the utility of this system in modeling diseases and the discovery, repositioning and testing on pharmaceuticals to ameliorate them. Expert opinion: Drosophila offers a facile and economical whole animal system with many homologous organs to humans, high functional conservation and established methods of generating and validating human disease models. Nevertheless, it remains relatively underused as a drug discovery tool probably because its relevance to mammalian systems remains under question. However, recent exciting success stories using Drosophila disease models for drug screening, repositioning and validation strongly suggest that fly models should figure prominently in the drug discovery pipeline from bench to bedside.
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Affiliation(s)
- Katerina Papanikolopoulou
- a Division of Neuroscience , Biomedical Sciences Research Centre "Alexander Fleming" , Vari , Greece
| | - Amrit Mudher
- b Centre for Biological Sciences , University of Southampton , Southampton , UK
| | - Efthimios Skoulakis
- a Division of Neuroscience , Biomedical Sciences Research Centre "Alexander Fleming" , Vari , Greece
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33
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Song HL, Demirev AV, Kim NY, Kim DH, Yoon SY. Ouabain activates transcription factor EB and exerts neuroprotection in models of Alzheimer's disease. Mol Cell Neurosci 2018; 95:13-24. [PMID: 30594669 DOI: 10.1016/j.mcn.2018.12.007] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Revised: 12/20/2018] [Accepted: 12/26/2018] [Indexed: 11/24/2022] Open
Abstract
The number of neurofibrillary tangles containing abnormal hyperphosphorylated tau protein correlates with the degree of dementia in Alzheimer's disease (AD). In addition, autophagosome accumulation and disturbance of autophagy, the process by which toxic aggregate proteins are degraded in the cytosol, are also found in AD models. These indicate that regulation of the autophagy-lysosome system may be a potential therapeutic target for AD. Activation of transcription factor EB (TFEB), a master regulator of autophagy-lysosome system gene transcription, reduces the amount of tau in APP mice. Here, to identify potential therapeutic compounds for AD, we performed two types of screening to determine pharmacologically active compounds that increase 1) neuronal viability in okadaic acid-induced tau hyperphosphorylation-related neurodegeneration models and 2) nuclear localization of TFEB in high-contents screening. Ouabain, a cardiac glycoside, was discovered as a common hit compound in both screenings. It also exhibited a significant protective effect in tau transgenic fly and mouse models in vivo. This work demonstrates that ouabain enhances activation of TFEB through inhibition of the mTOR pathway and induces downstream autophagy-lysosomal gene expression and cellular restorative properties. Therefore, therapeutic approaches using ouabain reduce the accumulation of abnormal toxic tau in vitro and in vivo.
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Affiliation(s)
- Ha-Lim Song
- Department of Brain Science, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea; Bio-Medical Institute of Technology (BMIT), University of Ulsan College of Medicine, Seoul, Republic of Korea; Institute for Innovation in Neurodegenerative Diseases, ADEL, Inc., Seoul, Republic of Korea
| | - Atanas Vladimirov Demirev
- Department of Brain Science, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea; Bio-Medical Institute of Technology (BMIT), University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Na-Young Kim
- Department of Brain Science, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea; Bio-Medical Institute of Technology (BMIT), University of Ulsan College of Medicine, Seoul, Republic of Korea; Institute for Innovation in Neurodegenerative Diseases, ADEL, Inc., Seoul, Republic of Korea
| | - Dong-Hou Kim
- Department of Brain Science, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea; Bio-Medical Institute of Technology (BMIT), University of Ulsan College of Medicine, Seoul, Republic of Korea.
| | - Seung-Yong Yoon
- Department of Brain Science, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea; Bio-Medical Institute of Technology (BMIT), University of Ulsan College of Medicine, Seoul, Republic of Korea; Institute for Innovation in Neurodegenerative Diseases, ADEL, Inc., Seoul, Republic of Korea.
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Chiku T, Hayashishita M, Saito T, Oka M, Shinno K, Ohtake Y, Shimizu S, Asada A, Hisanaga SI, Iijima KM, Ando K. S6K/p70S6K1 protects against tau-mediated neurodegeneration by decreasing the level of tau phosphorylated at Ser262 in a Drosophila model of tauopathy. Neurobiol Aging 2018; 71:255-264. [DOI: 10.1016/j.neurobiolaging.2018.07.021] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Revised: 07/27/2018] [Accepted: 07/29/2018] [Indexed: 02/08/2023]
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35
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Passarella D, Goedert M. Beta-sheet assembly of Tau and neurodegeneration in Drosophila melanogaster. Neurobiol Aging 2018; 72:98-105. [PMID: 30240946 PMCID: PMC6327151 DOI: 10.1016/j.neurobiolaging.2018.07.022] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Revised: 07/21/2018] [Accepted: 07/29/2018] [Indexed: 12/23/2022]
Abstract
The assembly of Tau into abundant β-sheet-rich filaments characterizes human tauopathies. A pathological pathway leading from monomeric to filamentous Tau is believed to be at the heart of these diseases. However, in Drosophila models of Tauopathy, neurodegeneration has been observed in the absence of abundant Tau filaments. Here we investigated the role of Tau assembly into β-sheets by expressing wild-type and Δ306-311 human Tau-383 in the retina and brain of Drosophila. We analyzed both lines for eye abnormalities, brain vacuolization, Tau phosphorylation and assembly, as well as climbing activity and survival. Flies expressing wild-type Tau-383 showed MC-1 staining, Tau hyperphosphorylation, and neurodegeneration. By contrast, flies expressing Δ306-311 Tau-383 had less MC-1 staining, reduced Tau hyperphosphorylation, and no detectable neurodegeneration. Their climbing ability and lifespan were similar to those of nontransgenic flies. Fluorescence spectroscopy after addition of Thioflavin T, a dye that interacts with β-sheets, showed no signal when Δ306-311 Tau-383 was incubated with heparin. These findings demonstrate that the assembly of Tau into β-sheets is necessary for neurodegeneration.
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Vandal SE, Zheng X, Ahmad ST. Molecular Genetics of Frontotemporal Dementia Elucidated by Drosophila Models-Defects in Endosomal⁻Lysosomal Pathway. Int J Mol Sci 2018; 19:ijms19061714. [PMID: 29890743 PMCID: PMC6032313 DOI: 10.3390/ijms19061714] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2018] [Revised: 06/06/2018] [Accepted: 06/07/2018] [Indexed: 01/31/2023] Open
Abstract
Frontotemporal dementia (FTD) is the second most common senile neurodegenerative disease. FTD is a heterogeneous disease that can be classified into several subtypes. A mutation in CHMP2B locus (CHMP2Bintron5), which encodes a component of endosomal sorting complex required for transport-III (ESCRT-III), is associated with a rare hereditary subtype of FTD linked to chromosome 3 (FTD-3). ESCRT is involved in critical cellular processes such as multivesicular body (MVB) formation during endosomal–lysosomal pathway and autophagy. ESCRT mutants causes diverse physiological defects primarily due to accumulation of endosomes and defective MVBs resulting in misregulation of signaling pathways. Charged multivesicular body protein 2B (CHMP2B) is important for neuronal physiology which especially rely on precise regulation of protein homeostasis due to their post-mitotic status. Drosophila has proven to be an excellent model for charaterization of mechanistic underpinning of neurodegenerative disorders including FTD. In this review, current understanding of various FTD-related mutations is discussed with a focus on Drosophila models of CHMP2Bintron5-associated FTD.
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Affiliation(s)
- Sarah E Vandal
- Department of Biology, Colby College, 5720 Mayflower Hill, Waterville, ME 04901, USA.
| | - Xiaoyue Zheng
- Department of Biology, Colby College, 5720 Mayflower Hill, Waterville, ME 04901, USA.
| | - S Tariq Ahmad
- Department of Biology, Colby College, 5720 Mayflower Hill, Waterville, ME 04901, USA.
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37
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Lee J, Kim M, Itoh TQ, Lim C. Ataxin-2: A versatile posttranscriptional regulator and its implication in neural function. WILEY INTERDISCIPLINARY REVIEWS-RNA 2018; 9:e1488. [PMID: 29869836 DOI: 10.1002/wrna.1488] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2018] [Revised: 05/04/2018] [Accepted: 05/09/2018] [Indexed: 12/13/2022]
Abstract
Ataxin-2 (ATXN2) is a eukaryotic RNA-binding protein that is conserved from yeast to human. Genetic expansion of a poly-glutamine tract in human ATXN2 has been implicated in several neurodegenerative diseases, likely acting through gain-of-function effects. Emerging evidence, however, suggests that ATXN2 plays more direct roles in neural function via specific molecular and cellular pathways. ATXN2 and its associated protein complex control distinct steps in posttranscriptional gene expression, including poly-A tailing, RNA stabilization, microRNA-dependent gene silencing, and translational activation. Specific RNA substrates have been identified for the functions of ATXN2 in aspects of neural physiology, such as circadian rhythms and olfactory habituation. Genetic models of ATXN2 loss-of-function have further revealed its significance in stress-induced cytoplasmic granules, mechanistic target of rapamycin signaling, and cellular metabolism, all of which are crucial for neural homeostasis. Accordingly, we propose that molecular evolution has been selecting the ATXN2 protein complex as an important trans-acting module for the posttranscriptional control of diverse neural functions. This explains how ATXN2 intimately interacts with various neurodegenerative disease genes, and suggests that loss-of-function effects of ATXN2 could be therapeutic targets for ATXN2-related neurological disorders. This article is categorized under: RNA in Disease and Development > RNA in Disease RNA Interactions with Proteins and Other Molecules > Protein-RNA Interactions: Functional Implications.
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Affiliation(s)
- Jongbo Lee
- School of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan, South Korea
| | - Minjong Kim
- School of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan, South Korea
| | - Taichi Q Itoh
- Faculty of Arts and Science, Kyushu University, Fukuoka, Japan
| | - Chunghun Lim
- School of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan, South Korea
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38
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Liu QF, Jeon Y, Sung YW, Lee JH, Jeong H, Kim YM, Yun HS, Chin YW, Jeon S, Cho KS, Koo BS. Nardostachys jatamansi Ethanol Extract Ameliorates Aβ42 Cytotoxicity. Biol Pharm Bull 2018; 41:470-477. [DOI: 10.1248/bpb.b17-00750] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Quan Feng Liu
- Department of Oriental Medicine, Dongguk University
- Department of Oriental Neuropsychiatry, Graduate School of Oriental Medicine, Dongguk University
| | - Youngjae Jeon
- Department of Biological Sciences, Konkuk University
| | - Yung-wei Sung
- Department of Oriental Medicine, Dongguk University
- Department of Oriental Neuropsychiatry, Graduate School of Oriental Medicine, Dongguk University
| | - Jang Ho Lee
- Department of Biological Sciences, Konkuk University
| | - Haemin Jeong
- Department of Biological Sciences, Konkuk University
| | - Young-Mi Kim
- College of Pharmacy and Integrated Research Institute for Drug Development, Dongguk University-Seoul
| | - Hye Sup Yun
- Department of Biological Sciences, Konkuk University
| | - Young-Won Chin
- College of Pharmacy and Integrated Research Institute for Drug Development, Dongguk University-Seoul
| | - Songhee Jeon
- Dongguk University Research Institute of Biotechnology, Dongguk University
- Department of Biomedical Sciences, BK21 PLUS Center for Creative Biomedical Scientists at Chonnam National University
| | | | - Byung-Soo Koo
- Department of Oriental Medicine, Dongguk University
- Department of Oriental Neuropsychiatry, Graduate School of Oriental Medicine, Dongguk University
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Brehme M, Voisine C. Model systems of protein-misfolding diseases reveal chaperone modifiers of proteotoxicity. Dis Model Mech 2017; 9:823-38. [PMID: 27491084 PMCID: PMC5007983 DOI: 10.1242/dmm.024703] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Chaperones and co-chaperones enable protein folding and degradation, safeguarding the proteome against proteotoxic stress. Chaperones display dynamic responses to exogenous and endogenous stressors and thus constitute a key component of the proteostasis network (PN), an intricately regulated network of quality control and repair pathways that cooperate to maintain cellular proteostasis. It has been hypothesized that aging leads to chronic stress on the proteome and that this could underlie many age-associated diseases such as neurodegeneration. Understanding the dynamics of chaperone function during aging and disease-related proteotoxic stress could reveal specific chaperone systems that fail to respond to protein misfolding. Through the use of suppressor and enhancer screens, key chaperones crucial for proteostasis maintenance have been identified in model organisms that express misfolded disease-related proteins. This review provides a literature-based analysis of these genetic studies and highlights prominent chaperone modifiers of proteotoxicity, which include the HSP70-HSP40 machine and small HSPs. Taken together, these studies in model systems can inform strategies for therapeutic regulation of chaperone functionality, to manage aging-related proteotoxic stress and to delay the onset of neurodegenerative diseases.
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Affiliation(s)
- Marc Brehme
- Joint Research Center for Computational Biomedicine (JRC-COMBINE), RWTH Aachen University, 52062 Aachen, Germany
| | - Cindy Voisine
- Department of Biology, Northeastern Illinois University, Chicago, IL 60625, USA
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40
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Sharma N, Khurana N, Muthuraman A. Lower vertebrate and invertebrate models of Alzheimer's disease - A review. Eur J Pharmacol 2017; 815:312-323. [PMID: 28943103 DOI: 10.1016/j.ejphar.2017.09.017] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Revised: 08/20/2017] [Accepted: 09/13/2017] [Indexed: 02/07/2023]
Abstract
Alzheimer's disease is a common neurodegenerative disorder which is characterized by the presence of beta- amyloid protein and neurofibrillary tangles (NFTs) in the brain. Till now, various higher vertebrate models have been in use to study the pathophysiology of this disease. But, these models possess some limitations like ethical restrictions, high cost, difficult maintenance of large quantity and lesser reproducibility. Besides, various lower chordate animals like Danio rerio, Drosophila melanogaster, Caenorhabditis elegans and Ciona intestinalis have been proved to be an important model for the in vivo determination of targets of drugs with least limitations. In this article, we reviewed different studies conducted on theses models for the better understanding of the pathophysiology of AD and their subsequent application as a potential tool in the preclinical evaluation of new drugs.
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Affiliation(s)
- Neha Sharma
- Department of Pharmaceutical Sciences, Lovely Professional University, Phagwara, Punjab, India
| | - Navneet Khurana
- Department of Pharmaceutical Sciences, Lovely Professional University, Phagwara, Punjab, India
| | - Arunachalam Muthuraman
- Department of Pharmacology, Akal College of Pharmacy and Technical Education, Mastuana Sahib, Sangrur, Punjab, India; Department of Pharmacology, JSS College of Pharmacy, Jagadguru Sri Shivarathreeshwara University, Mysuru 570015, Karnataka, India.
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41
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Dräger NM, Nachman E, Winterhoff M, Brühmann S, Shah P, Katsinelos T, Boulant S, Teleman AA, Faix J, Jahn TR. Bin1 directly remodels actin dynamics through its BAR domain. EMBO Rep 2017; 18:2051-2066. [PMID: 28893863 DOI: 10.15252/embr.201744137] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2017] [Revised: 08/07/2017] [Accepted: 08/08/2017] [Indexed: 11/09/2022] Open
Abstract
Endocytic processes are facilitated by both curvature-generating BAR-domain proteins and the coordinated polymerization of actin filaments. Under physiological conditions, the N-BAR protein Bin1 has been shown to sense and curve membranes in a variety of cellular processes. Recent studies have identified Bin1 as a risk factor for Alzheimer's disease, although its possible pathological function in neurodegeneration is currently unknown. Here, we report that Bin1 not only shapes membranes, but is also directly involved in actin binding through its BAR domain. We observed a moderate actin bundling activity by human Bin1 and describe its ability to stabilize actin filaments against depolymerization. Moreover, Bin1 is also involved in stabilizing tau-induced actin bundles, which are neuropathological hallmarks of Alzheimer's disease. We also provide evidence for this effect in vivo, where we observed that downregulation of Bin1 in a Drosophila model of tauopathy significantly reduces the appearance of tau-induced actin inclusions. Together, these findings reveal the ability of Bin1 to modify actin dynamics and provide a possible mechanistic connection between Bin1 and tau-induced pathobiological changes of the actin cytoskeleton.
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Affiliation(s)
- Nina M Dräger
- Proteostasis in Neurodegenerative Disease (B180), Schaller Research Group at the University of Heidelberg and DKFZ, Heidelberg, Germany
| | - Eliana Nachman
- Proteostasis in Neurodegenerative Disease (B180), Schaller Research Group at the University of Heidelberg and DKFZ, Heidelberg, Germany.,German Cancer Research Center (DKFZ), DKFZ-ZMBH Alliance, Center for Molecular Biology of Heidelberg University (ZMBH), Heidelberg, Germany
| | - Moritz Winterhoff
- Institute for Biophysical Chemistry, Hannover Medical School, Hannover, Germany
| | - Stefan Brühmann
- Institute for Biophysical Chemistry, Hannover Medical School, Hannover, Germany
| | - Pranav Shah
- Schaller Research Group at CellNetworks, Department of Infectious Diseases, Virology, Heidelberg University, Heidelberg, Germany.,Cellular polarity and viral infection (F140), German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Taxiarchis Katsinelos
- Proteostasis in Neurodegenerative Disease (B180), Schaller Research Group at the University of Heidelberg and DKFZ, Heidelberg, Germany
| | - Steeve Boulant
- Schaller Research Group at CellNetworks, Department of Infectious Diseases, Virology, Heidelberg University, Heidelberg, Germany.,Cellular polarity and viral infection (F140), German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Aurelio A Teleman
- Signal Transduction in Cancer and Metabolism (B140), German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Jan Faix
- Institute for Biophysical Chemistry, Hannover Medical School, Hannover, Germany
| | - Thomas R Jahn
- Proteostasis in Neurodegenerative Disease (B180), Schaller Research Group at the University of Heidelberg and DKFZ, Heidelberg, Germany
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42
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Auburger G, Sen NE, Meierhofer D, Başak AN, Gitler AD. Efficient Prevention of Neurodegenerative Diseases by Depletion of Starvation Response Factor Ataxin-2. Trends Neurosci 2017; 40:507-516. [DOI: 10.1016/j.tins.2017.06.004] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Accepted: 06/09/2017] [Indexed: 12/13/2022]
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43
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Kim M, Ho A, Lee JH. Autophagy and Human Neurodegenerative Diseases-A Fly's Perspective. Int J Mol Sci 2017; 18:ijms18071596. [PMID: 28737703 PMCID: PMC5536083 DOI: 10.3390/ijms18071596] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Revised: 07/12/2017] [Accepted: 07/21/2017] [Indexed: 12/18/2022] Open
Abstract
Neurodegenerative diseases in humans are frequently associated with prominent accumulation of toxic protein inclusions and defective organelles. Autophagy is a process of bulk lysosomal degradation that eliminates these harmful substances and maintains the subcellular environmental quality. In support of autophagy's importance in neuronal homeostasis, several genetic mutations that interfere with autophagic processes were found to be associated with familial neurodegenerative disorders. In addition, genetic mutations in autophagy-regulating genes provoked neurodegenerative phenotypes in animal models. The Drosophila model significantly contributed to these recent developments, which led to the theory that autophagy dysregulation is one of the major underlying causes of human neurodegenerative disorders. In the current review, we discuss how studies using Drosophila enhanced our understanding of the relationship between autophagy and neurodegenerative processes.
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Affiliation(s)
- Myungjin Kim
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI 48109, USA.
| | - Allison Ho
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI 48109, USA.
| | - Jun Hee Lee
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI 48109, USA.
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44
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Fernius J, Starkenberg A, Pokrzywa M, Thor S. Human TTBK1, TTBK2 and MARK1 kinase toxicity in Drosophila melanogaster is exacerbated by co-expression of human Tau. Biol Open 2017; 6:1013-1023. [PMID: 28711868 PMCID: PMC5550906 DOI: 10.1242/bio.022749] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Tau protein is involved in numerous human neurodegenerative diseases, and Tau hyper-phosphorylation has been linked to Tau aggregation and toxicity. Previous studies have addressed toxicity and phospho-biology of human Tau (hTau) in Drosophila melanogaster. However, hTau transgenes have most often been randomly inserted in the genome, thus making it difficult to compare between different hTau isoforms and phospho-mutants. In addition, many studies have expressed hTau also in mitotic cells, causing non-physiological toxic effects. Here, we overcome these confounds by integrating UAS-hTau isoform transgenes into specific genomic loci, and express hTau post-mitotically in the Drosophila nervous system. Lifespan and locomotor analyses show that all six of the hTau isoforms elicit similar toxicity in flies, although hTau2N3R showed somewhat elevated toxicity. To determine if Tau phosphorylation is responsible for toxicity, we analyzed the effects of co-expressing hTau isoforms together with Tau-kinases, focusing on TTBK1, TTBK2 and MARK1. We observed toxicity when expressing each of the three kinases alone, or in combination. Kinase toxicity was enhanced by hTau co-expression, with strongest co-toxicity for TTBK1. Mutagenesis and phosphorylation analysis indicates that hTau-MARK1 combinatorial toxicity may be due to direct phosphorylation of hTau, while hTau-TTBK1/2 combinatorial toxicity may result from independent toxicity mechanisms. Summary: Tau hyper-phosphorylation has been linked to toxicity, but the Tau isoforms, kinases and residues remain unclear. Using the Drosophila model, we find evidence for involvement of TTBK and MARK kinases.
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Affiliation(s)
- Josefin Fernius
- Department of Clinical and Experimental Medicine, Linkoping University, Linkoping SE-581 85, Sweden
| | - Annika Starkenberg
- Department of Clinical and Experimental Medicine, Linkoping University, Linkoping SE-581 85, Sweden
| | - Malgorzata Pokrzywa
- Department of Clinical and Experimental Medicine, Linkoping University, Linkoping SE-581 85, Sweden
| | - Stefan Thor
- Department of Clinical and Experimental Medicine, Linkoping University, Linkoping SE-581 85, Sweden
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45
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Ataxin-2: From RNA Control to Human Health and Disease. Genes (Basel) 2017; 8:genes8060157. [PMID: 28587229 PMCID: PMC5485521 DOI: 10.3390/genes8060157] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Revised: 05/23/2017] [Accepted: 05/31/2017] [Indexed: 12/13/2022] Open
Abstract
RNA-binding proteins play fundamental roles in the regulation of molecular processes critical to cellular and organismal homeostasis. Recent studies have identified the RNA-binding protein Ataxin-2 as a genetic determinant or risk factor for various diseases including spinocerebellar ataxia type II (SCA2) and amyotrophic lateral sclerosis (ALS), amongst others. Here, we first discuss the increasingly wide-ranging molecular functions of Ataxin-2, from the regulation of RNA stability and translation to the repression of deleterious accumulation of the RNA-DNA hybrid-harbouring R-loop structures. We also highlight the broader physiological roles of Ataxin-2 such as in the regulation of cellular metabolism and circadian rhythms. Finally, we discuss insight from clinically focused studies to shed light on the impact of molecular and physiological roles of Ataxin-2 in various human diseases. We anticipate that deciphering the fundamental functions of Ataxin-2 will uncover unique approaches to help cure or control debilitating and lethal human diseases.
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Abstract
Drosophila is a powerful model to study human diseases thanks to its genetic tools and ease of screening. Human genes can be expressed in targeted organs and their toxicity assessed on easily scorable external phenotypes that can be used as readout to perform genetic screen of toxicity modifiers. In this chapter, I describe how to express human Tau protein in the Drosophila eye, assess protein expression by western blot, assess Tau toxicity by quantifying the size of the Tau-induced rough eye, and perform a genetic screen of modifiers of Tau toxicity in the Drosophila eye.
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Affiliation(s)
- Pierre Dourlen
- Institut Pasteur de Lille, INSERM, UMR1167, Université de Lille, 1 rue du Prof. Calmette, 59019, Lille, France.
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47
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Modelling in miniature: Using Drosophila melanogaster to study human neurodegeneration. ACTA ACUST UNITED AC 2017. [DOI: 10.1016/j.ddmod.2018.09.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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48
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49
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Seidel G, Meierhofer D, Şen NE, Guenther A, Krobitsch S, Auburger G. Quantitative Global Proteomics of Yeast PBP1 Deletion Mutants and Their Stress Responses Identifies Glucose Metabolism, Mitochondrial, and Stress Granule Changes. J Proteome Res 2016; 16:504-515. [PMID: 27966978 DOI: 10.1021/acs.jproteome.6b00647] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The yeast protein PBP1 is implicated in very diverse pathways. Intriguingly, its deletion mitigates the toxicity of human neurodegeneration factors. Here, we performed label-free quantitative global proteomics to identify crucial downstream factors, either without stress or under cell stress conditions (heat and NaN3). Compared to the wildtype BY4741 strain, PBP1 deletion always triggered downregulation of the key bioenergetics enzyme KGD2 and the prion protein RNQ1 as well as upregulation of the leucine biosynthesis enzyme LEU1. Without stress, enrichment of stress response factors was consistently detected for both deletion mutants; upon stress, these factors were more pronounced. The selective analysis of components of stress granules and P-bodies revealed a prominent downregulation of GIS2. Our yeast data are in good agreement with a global proteomics and metabolomics publication that the PBP1 ortholog ATAXIN-2 (ATXN2) knockout (KO) in mouse results in mitochondrial deficits in leucine/fatty acid catabolism and bioenergetics, with an obesity phenotype. Furthermore, our data provide the completely novel insight that PBP1 mutations in stress periods involve GIS2, a plausible scenario in view of previous data that both PBP1 and GIS2 relocalize from ribosomes to stress granules, interact with poly(A)-binding protein in translation regulation and prevent mitochondrial precursor overaccumulation stress (mPOS). This may be relevant for human diseases like spinocerebellar ataxias, amyotrophic lateral sclerosis, and the metabolic syndrome.
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Affiliation(s)
- Gunnar Seidel
- Max Planck Institute for Molecular Genetics, Ihnestraße 63-73, 14195 Berlin, Germany
| | - David Meierhofer
- Max Planck Institute for Molecular Genetics, Ihnestraße 63-73, 14195 Berlin, Germany
| | - Nesli-Ece Şen
- Experimental Neurology, Goethe University Medical School , Theodor Stern Kai 7, 60590 Frankfurt am Main, Germany
| | - Anika Guenther
- Max Planck Institute for Molecular Genetics, Ihnestraße 63-73, 14195 Berlin, Germany
| | - Sylvia Krobitsch
- Max Planck Institute for Molecular Genetics, Ihnestraße 63-73, 14195 Berlin, Germany
| | - Georg Auburger
- Experimental Neurology, Goethe University Medical School , Theodor Stern Kai 7, 60590 Frankfurt am Main, Germany
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50
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Frenkel-Pinter M, Tal S, Scherzer-Attali R, Abu-Hussien M, Alyagor I, Eisenbaum T, Gazit E, Segal D. Naphthoquinone-Tryptophan Hybrid Inhibits Aggregation of the Tau-Derived Peptide PHF6 and Reduces Neurotoxicity. J Alzheimers Dis 2016; 51:165-78. [PMID: 26836184 DOI: 10.3233/jad-150927] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Tauopathies, such as Alzheimer's disease (AD), are a group of disorders characterized neuropathologically by intracellular toxic accumulations of abnormal protein aggregates formed by misfolding of the microtubule-associated protein tau. Since protein self-assembly appears to be an initial key step in the pathology of this group of diseases, intervening in this process can be both a prophylactic measure and a means for modifying the course of the disease for therapeutic purposes. We and others have shown that aromatic small molecules can be effective inhibitors of aggregation of various protein assemblies, by binding to the aromatic core in aggregation-prone motifs and preventing their self-assembly. Specifically, we have designed a series of small aromatic naphthoquinone-tryptophan hybrid molecules as candidate aggregation inhibitors of β -sheet based assembly and demonstrated their efficacy toward inhibiting aggregation of the amyloid-β peptide, another culprit of AD, as well as of various other aggregative proteins involved in other protein misfolding diseases. Here we tested whether a leading naphthoquinone-tryptophan hybrid molecule, namely NQTrp, can be repurposed as an inhibitor of the aggregation of the tau protein in vitro and in vivo. We show that the molecule inhibits the in vitro assembly of PHF6, the aggregation-prone fragment of tau protein, reduces hyperphosphorylated tau deposits and ameliorates tauopathy-related behavioral defect in an established transgenic Drosophila model expressing human tau. We suggest that NQTrp, or optimized versions of it, could act as novel disease modifying drugs for AD and other tauopathies.
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