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Shwab EK, Gingerich DC, Man Z, Gamache J, Garrett ME, Crawford GE, Ashley-Koch AE, Serrano GE, Beach TG, Lutz MW, Chiba-Falek O. Single-nucleus multi-omics of Parkinson's disease reveals a glutamatergic neuronal subtype susceptible to gene dysregulation via alteration of transcriptional networks. Acta Neuropathol Commun 2024; 12:111. [PMID: 38956662 PMCID: PMC11218415 DOI: 10.1186/s40478-024-01803-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2024] [Accepted: 05/27/2024] [Indexed: 07/04/2024] Open
Abstract
The genetic architecture of Parkinson's disease (PD) is complex and multiple brain cell subtypes are involved in the neuropathological progression of the disease. Here we aimed to advance our understanding of PD genetic complexity at a cell subtype precision level. Using parallel single-nucleus (sn)RNA-seq and snATAC-seq analyses we simultaneously profiled the transcriptomic and chromatin accessibility landscapes in temporal cortex tissues from 12 PD compared to 12 control subjects at a granular single cell resolution. An integrative bioinformatic pipeline was developed and applied for the analyses of these snMulti-omics datasets. The results identified a subpopulation of cortical glutamatergic excitatory neurons with remarkably altered gene expression in PD, including differentially-expressed genes within PD risk loci identified in genome-wide association studies (GWAS). This was the only neuronal subtype showing significant and robust overexpression of SNCA. Further characterization of this neuronal-subpopulation showed upregulation of specific pathways related to axon guidance, neurite outgrowth and post-synaptic structure, and downregulated pathways involved in presynaptic organization and calcium response. Additionally, we characterized the roles of three molecular mechanisms in governing PD-associated cell subtype-specific dysregulation of gene expression: (1) changes in cis-regulatory element accessibility to transcriptional machinery; (2) changes in the abundance of master transcriptional regulators, including YY1, SP3, and KLF16; (3) candidate regulatory variants in high linkage disequilibrium with PD-GWAS genomic variants impacting transcription factor binding affinities. To our knowledge, this study is the first and the most comprehensive interrogation of the multi-omics landscape of PD at a cell-subtype resolution. Our findings provide new insights into a precise glutamatergic neuronal cell subtype, causal genes, and non-coding regulatory variants underlying the neuropathological progression of PD, paving the way for the development of cell- and gene-targeted therapeutics to halt disease progression as well as genetic biomarkers for early preclinical diagnosis.
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Affiliation(s)
- E Keats Shwab
- Division of Translational Brain Sciences, Department of Neurology, Duke University School of Medicine, Duke University Medical Center, Durham, NC, 27710, USA
- Center for Genomic and Computational Biology, Duke University Medical Center, Durham, NC, 27708, USA
| | - Daniel C Gingerich
- Division of Translational Brain Sciences, Department of Neurology, Duke University School of Medicine, Duke University Medical Center, Durham, NC, 27710, USA
- Center for Genomic and Computational Biology, Duke University Medical Center, Durham, NC, 27708, USA
| | - Zhaohui Man
- Division of Translational Brain Sciences, Department of Neurology, Duke University School of Medicine, Duke University Medical Center, Durham, NC, 27710, USA
- Center for Genomic and Computational Biology, Duke University Medical Center, Durham, NC, 27708, USA
| | - Julia Gamache
- Division of Translational Brain Sciences, Department of Neurology, Duke University School of Medicine, Duke University Medical Center, Durham, NC, 27710, USA
- Center for Genomic and Computational Biology, Duke University Medical Center, Durham, NC, 27708, USA
| | - Melanie E Garrett
- Duke Molecular Physiology Institute, Duke University Medical Center, Durham, NC, 27701, USA
| | - Gregory E Crawford
- Center for Genomic and Computational Biology, Duke University Medical Center, Durham, NC, 27708, USA
- Division of Medical Genetics, Department of Pediatrics, Duke University Medical Center, Durham, NC, 27708, USA
- Center for Advanced Genomic Technologies, Duke University Medical Center, Durham, NC, 27708, USA
| | - Allison E Ashley-Koch
- Duke Molecular Physiology Institute, Duke University Medical Center, Durham, NC, 27701, USA
- Department of Medicine, Duke University Medical Center, Durham, NC, 27708, USA
| | - Geidy E Serrano
- Banner Sun Health Research Institute, Sun City, AZ, 85351, USA
| | - Thomas G Beach
- Banner Sun Health Research Institute, Sun City, AZ, 85351, USA
| | - Michael W Lutz
- Division of Translational Brain Sciences, Department of Neurology, Duke University School of Medicine, Duke University Medical Center, Durham, NC, 27710, USA
| | - Ornit Chiba-Falek
- Division of Translational Brain Sciences, Department of Neurology, Duke University School of Medicine, Duke University Medical Center, Durham, NC, 27710, USA.
- Center for Genomic and Computational Biology, Duke University Medical Center, Durham, NC, 27708, USA.
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2
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Khan MR, Yin X, Kang SU, Mitra J, Wang H, Ryu T, Brahmachari S, Karuppagounder SS, Kimura Y, Jhaldiyal A, Kim HH, Gu H, Chen R, Redding-Ochoa J, Troncoso J, Na CH, Ha T, Dawson VL, Dawson TM. Enhanced mTORC1 signaling and protein synthesis in pathologic α-synuclein cellular and animal models of Parkinson's disease. Sci Transl Med 2023; 15:eadd0499. [PMID: 38019930 DOI: 10.1126/scitranslmed.add0499] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Accepted: 10/10/2023] [Indexed: 12/01/2023]
Abstract
Pathologic α-synuclein plays an important role in the pathogenesis of α-synucleinopathies such as Parkinson's disease (PD). Disruption of proteostasis is thought to be central to pathologic α-synuclein toxicity; however, the molecular mechanism of this deregulation is poorly understood. Complementary proteomic approaches in cellular and animal models of PD were used to identify and characterize the pathologic α-synuclein interactome. We report that the highest biological processes that interacted with pathologic α-synuclein in mice included RNA processing and translation initiation. Regulation of catabolic processes that include autophagy were also identified. Pathologic α-synuclein was found to bind with the tuberous sclerosis protein 2 (TSC2) and to trigger the activation of the mammalian target of rapamycin (mTOR) complex 1 (mTORC1), which augmented mRNA translation and protein synthesis, leading to neurodegeneration. Genetic and pharmacologic inhibition of mTOR and protein synthesis rescued the dopamine neuron loss, behavioral deficits, and aberrant biochemical signaling in the α-synuclein preformed fibril mouse model and Drosophila transgenic models of pathologic α-synuclein-induced degeneration. Pathologic α-synuclein furthermore led to a destabilization of the TSC1-TSC2 complex, which plays an important role in mTORC1 activity. Constitutive overexpression of TSC2 rescued motor deficits and neuropathology in α-synuclein flies. Biochemical examination of PD postmortem brain tissues also suggested deregulated mTORC1 signaling. These findings establish a connection between mRNA translation deregulation and mTORC1 pathway activation that is induced by pathologic α-synuclein in cellular and animal models of PD.
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Affiliation(s)
- Mohammed Repon Khan
- Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Diana Helis Henry Medical Research Foundation, New Orleans, LA 70130-2685, USA
| | - Xiling Yin
- Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Diana Helis Henry Medical Research Foundation, New Orleans, LA 70130-2685, USA
| | - Sung-Ung Kang
- Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Diana Helis Henry Medical Research Foundation, New Orleans, LA 70130-2685, USA
| | - Jaba Mitra
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Hu Wang
- Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Diana Helis Henry Medical Research Foundation, New Orleans, LA 70130-2685, USA
| | - Taekyung Ryu
- Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Saurav Brahmachari
- Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Diana Helis Henry Medical Research Foundation, New Orleans, LA 70130-2685, USA
| | - Senthilkumar S Karuppagounder
- Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Diana Helis Henry Medical Research Foundation, New Orleans, LA 70130-2685, USA
| | - Yasuyoshi Kimura
- Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Aanishaa Jhaldiyal
- Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Hyun Hee Kim
- Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Hao Gu
- Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Rong Chen
- Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Javier Redding-Ochoa
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Department of Pathology (Neuropathology), Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Juan Troncoso
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Department of Pathology (Neuropathology), Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Chan Hyun Na
- Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Taekjip Ha
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Howard Hughes Medical Institute, Baltimore, MD 21205, USA
| | - Valina L Dawson
- Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Diana Helis Henry Medical Research Foundation, New Orleans, LA 70130-2685, USA
- Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Ted M Dawson
- Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Diana Helis Henry Medical Research Foundation, New Orleans, LA 70130-2685, USA
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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LaForce GR, Philippidou P, Schaffer AE. mRNA isoform balance in neuronal development and disease. WILEY INTERDISCIPLINARY REVIEWS. RNA 2023; 14:e1762. [PMID: 36123820 PMCID: PMC10024649 DOI: 10.1002/wrna.1762] [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: 03/29/2022] [Revised: 07/11/2022] [Accepted: 08/15/2022] [Indexed: 11/07/2022]
Abstract
Balanced mRNA isoform diversity and abundance are spatially and temporally regulated throughout cellular differentiation. The proportion of expressed isoforms contributes to cell type specification and determines key properties of the differentiated cells. Neurons are unique cell types with intricate developmental programs, characteristic cellular morphologies, and electrophysiological potential. Neuron-specific gene expression programs establish these distinctive cellular characteristics and drive diversity among neuronal subtypes. Genes with neuron-specific alternative processing are enriched in key neuronal functions, including synaptic proteins, adhesion molecules, and scaffold proteins. Despite the similarity of neuronal gene expression programs, each neuronal subclass can be distinguished by unique alternative mRNA processing events. Alternative processing of developmentally important transcripts alters coding and regulatory information, including interaction domains, transcript stability, subcellular localization, and targeting by RNA binding proteins. Fine-tuning of mRNA processing is essential for neuronal activity and maintenance. Thus, the focus of neuronal RNA biology research is to dissect the transcriptomic mechanisms that underlie neuronal homeostasis, and consequently, predispose neuronal subtypes to disease. This article is categorized under: RNA in Disease and Development > RNA in Disease RNA in Disease and Development > RNA in Development.
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Affiliation(s)
- Geneva R LaForce
- Department of Genetics and Genome Sciences, Case Western Reserve University, Cleveland, Ohio, USA
| | - Polyxeni Philippidou
- Department of Neurosciences, Case Western Reserve University, Cleveland, Ohio, USA
| | - Ashleigh E Schaffer
- Department of Genetics and Genome Sciences, Case Western Reserve University, Cleveland, Ohio, USA
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Villalobos-Cantor S, Barrett RM, Condon AF, Arreola-Bustos A, Rodriguez KM, Cohen MS, Martin I. Rapid cell type-specific nascent proteome labeling in Drosophila. eLife 2023; 12:83545. [PMID: 37092974 PMCID: PMC10125018 DOI: 10.7554/elife.83545] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2022] [Accepted: 04/09/2023] [Indexed: 04/25/2023] Open
Abstract
Controlled protein synthesis is required to regulate gene expression and is often carried out in a cell type-specific manner. Protein synthesis is commonly measured by labeling the nascent proteome with amino acid analogs or isotope-containing amino acids. These methods have been difficult to implement in vivo as they require lengthy amino acid replacement procedures. O-propargyl-puromycin (OPP) is a puromycin analog that incorporates into nascent polypeptide chains. Through its terminal alkyne, OPP can be conjugated to a fluorophore-azide for directly visualizing nascent protein synthesis, or to a biotin-azide for capture and identification of newly-synthesized proteins. To achieve cell type-specific OPP incorporation, we developed phenylacetyl-OPP (PhAc-OPP), a puromycin analog harboring an enzyme-labile blocking group that can be removed by penicillin G acylase (PGA). Here, we show that cell type-specific PGA expression in Drosophila can be used to achieve OPP labeling of newly-synthesized proteins in targeted cell populations within the brain. Following a brief 2 hr incubation of intact brains with PhAc-OPP, we observe robust imaging and affinity purification of OPP-labeled nascent proteins in PGA-targeted cell populations. We apply this method to show a pronounced age-related decline in neuronal protein synthesis in the fly brain, demonstrating the capability of PhAc-OPP to quantitatively capture in vivo protein synthesis states. This method, which we call POPPi (PGA-dependent OPP incorporation), should be applicable for rapidly visualizing protein synthesis and identifying nascent proteins synthesized under diverse physiological and pathological conditions with cellular specificity in vivo.
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Affiliation(s)
- Stefanny Villalobos-Cantor
- Jungers Center for Neurosciences, Department of Neurology, Oregon Health and Science University, Portland, United States
| | - Ruth M Barrett
- Jungers Center for Neurosciences, Department of Neurology, Oregon Health and Science University, Portland, United States
| | - Alec F Condon
- Jungers Center for Neurosciences, Department of Neurology, Oregon Health and Science University, Portland, United States
| | - Alicia Arreola-Bustos
- Jungers Center for Neurosciences, Department of Neurology, Oregon Health and Science University, Portland, United States
| | - Kelsie M Rodriguez
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, United States
| | - Michael S Cohen
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, United States
| | - Ian Martin
- Jungers Center for Neurosciences, Department of Neurology, Oregon Health and Science University, Portland, United States
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, United States
- Parkinson Center of Oregon, Oregon Health and Science University, Portland, United States
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5
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Cuttler K, Fortuin S, Müller-Nedebock AC, Vlok M, Cloete R, Bardien S. Proteomics analysis of the p.G849D variant in neurexin 2 alpha may reveal insight into Parkinson’s disease pathobiology. Front Aging Neurosci 2022; 14:1002777. [DOI: 10.3389/fnagi.2022.1002777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Accepted: 11/08/2022] [Indexed: 12/02/2022] Open
Abstract
Parkinson’s disease (PD), the fastest-growing neurological disorder globally, has a complex etiology. A previous study by our group identified the p.G849D variant in neurexin 2 (NRXN2), encoding the synaptic protein, NRXN2α, as a possible causal variant of PD. Therefore, we aimed to perform functional studies using proteomics in an attempt to understand the biological pathways affected by the variant. We hypothesized that this may reveal insight into the pathobiology of PD. Wild-type and mutant NRXN2α plasmids were transfected into SH-SY5Y cells. Thereafter, total protein was extracted and prepared for mass spectrometry using a Thermo Scientific Fusion mass spectrometer equipped with a Nanospray Flex ionization source. The data were then interrogated against the UniProt H. sapiens database and afterward, pathway and enrichment analyses were performed using in silico tools. Overexpression of the wild-type protein led to the enrichment of proteins involved in neurodegenerative diseases, while overexpression of the mutant protein led to the decline of proteins involved in ribosomal functioning. Thus, we concluded that the wild-type NRXN2α may be involved in pathways related to the development of neurodegenerative disorders, and that biological processes related to the ribosome, transcription, and tRNA, specifically at the synapse, could be an important mechanism in PD. Future studies targeting translation at the synapse in PD could therefore provide further information on the pathobiology of the disease.
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Pereira MCL, Boese AC, Murad R, Yin J, Hamblin MH, Lee JP. Reduced dopaminergic neuron degeneration and global transcriptional changes in Parkinson's disease mouse brains engrafted with human neural stems during the early disease stage. Exp Neurol 2022; 352:114042. [PMID: 35271839 DOI: 10.1016/j.expneurol.2022.114042] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 02/16/2022] [Accepted: 03/03/2022] [Indexed: 02/08/2023]
Abstract
INTRODUCTION Current stem cell therapies for Parkinson's disease (PD) focus on a neurorestorative approach that aims to repair the CNS during the symptomatic phase. However, the pleiotropic and supportive effects of human neural stem cells (hNSCs) may make them effective for PD treatment during the disease's earlier stages. In the current study, we investigated the therapeutic effects of transplanting hNSCs during the early stages of PD development when most dopaminergic neurons are still present and before symptoms appear. Previous studies on hNSCs in Parkinson's disease focus on the substantia nigra and its immediate surroundings, but other brain structures are affected in PD as well. Here, we investigated the therapeutic effects of hNSCs on the entire PD-afflicted brain transcriptome using RNA sequencing (RNA-seq). METHODS PD was induced with a single intranasal infusion of 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP) and hNSCs were transplanted unilaterally into the striatum one week later. The timepoint for hNSC transplantation coincided with upregulation of endogenous proinflammatory cytokines in the CNS, which play a role in stem cell migration. At 3 weeks post-transplantation (4 weeks post-MPTP), we assessed motor symptoms through behavioral tests, quantified dopaminergic neurons in the substantia nigra, and performed global transcriptional profiling to understand the mechanism underlying the effect of hNSCs on dopaminergic neuron degeneration. RESULTS We found that early hNSC engraftment mitigated motor symptoms induced by MPTP, and also reduced MPTP-induced loss of dopaminergic neurons. In this study, we uniquely presented the first comprehensive analysis of the effect of hNSC transplantation on the transcriptional profiling of PD mouse brains showing decreased expression of 249 and increased expression of 200 genes. These include genes implicated in mitochondrial bioenergetics, proteostasis, and other signaling pathways associated with improved PD outcome following hNSC transplantation. CONCLUSION These findings indicate that NSC transplantation during the asymptomatic phase of PD may limit or halt the progression of this neurodegenerative disorder. Transcriptional profiling of hNSC-engrafted PD mouse brains provides mechanistic insight that could lead to novel approaches to ameliorating degeneration of dopaminergic neurons and improving behavioral dysfunction in PD.
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Affiliation(s)
- Marcia C L Pereira
- Department of Physiology, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Austin C Boese
- Department of Physiology, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Rabi Murad
- Bioinformatics, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | - Jun Yin
- Bioinformatics, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | - Milton H Hamblin
- Tulane University Health Sciences Center, Tulane University, New Orleans, LA 70112, USA
| | - Jean-Pyo Lee
- Department of Physiology, Tulane University School of Medicine, New Orleans, LA 70112, USA.
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7
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Novak G, Kyriakis D, Grzyb K, Bernini M, Rodius S, Dittmar G, Finkbeiner S, Skupin A. Single-cell transcriptomics of human iPSC differentiation dynamics reveal a core molecular network of Parkinson's disease. Commun Biol 2022; 5:49. [PMID: 35027645 PMCID: PMC8758783 DOI: 10.1038/s42003-021-02973-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 12/14/2021] [Indexed: 01/02/2023] Open
Abstract
Parkinson's disease (PD) is the second-most prevalent neurodegenerative disorder, characterized by the loss of dopaminergic neurons (mDA) in the midbrain. The underlying mechanisms are only partly understood and there is no treatment to reverse PD progression. Here, we investigated the disease mechanism using mDA neurons differentiated from human induced pluripotent stem cells (hiPSCs) carrying the ILE368ASN mutation within the PINK1 gene, which is strongly associated with PD. Single-cell RNA sequencing (RNAseq) and gene expression analysis of a PINK1-ILE368ASN and a control cell line identified genes differentially expressed during mDA neuron differentiation. Network analysis revealed that these genes form a core network, members of which interact with all known 19 protein-coding Parkinson's disease-associated genes. This core network encompasses key PD-associated pathways, including ubiquitination, mitochondrial function, protein processing, RNA metabolism, and vesicular transport. Proteomics analysis showed a consistent alteration in proteins of dopamine metabolism, indicating a defect of dopaminergic metabolism in PINK1-ILE368ASN neurons. Our findings suggest the existence of a network onto which pathways associated with PD pathology converge, and offers an inclusive interpretation of the phenotypic heterogeneity of PD.
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Affiliation(s)
- Gabriela Novak
- The Integrative Cell Signalling Group, Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, Esch-sur-Alzette, Luxembourg.
- Luxembourg Institute of Health (LIH), Esch-sur-Alzette, Luxembourg.
- Center for Systems and Therapeutics, the Gladstone Institutes and Departments of Neurology and Physiology, University of California, San Francisco, San Francisco, CA, 94158, USA.
| | - Dimitrios Kyriakis
- The Integrative Cell Signalling Group, Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | - Kamil Grzyb
- The Integrative Cell Signalling Group, Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | - Michela Bernini
- The Integrative Cell Signalling Group, Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | - Sophie Rodius
- Department of Infection and Immunity, Luxembourg Institute of Health, Strassen, Luxembourg
| | - Gunnar Dittmar
- Department of Infection and Immunity, Luxembourg Institute of Health, Strassen, Luxembourg
- Department of Life Sciences and Medicine, University of Luxembourg, Belvaux, Luxembourg
| | - Steven Finkbeiner
- Center for Systems and Therapeutics, the Gladstone Institutes and Departments of Neurology and Physiology, University of California, San Francisco, San Francisco, CA, 94158, USA
| | - Alexander Skupin
- The Integrative Cell Signalling Group, Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, Esch-sur-Alzette, Luxembourg.
- University of California San Diego, La Jolla, CA, 92093, USA.
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8
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Khlebodarova TM. The molecular view of mechanical stress of brain cells, local translation, and neurodegenerative diseases. Vavilovskii Zhurnal Genet Selektsii 2021; 25:92-100. [PMID: 34901706 PMCID: PMC8629365 DOI: 10.18699/vj21.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 12/21/2020] [Accepted: 12/22/2020] [Indexed: 12/03/2022] Open
Abstract
The assumption that chronic mechanical stress in brain cells stemming from intracranial hypertension,
arterial hypertension, or mechanical injury is a risk factor for neurodegenerative diseases was put forward in the
1990s and has since been supported. However, the molecular mechanisms that underlie the way from cell exposure to mechanical stress to disturbances in synaptic plasticity followed by changes in behavior, cognition, and
memory are still poorly understood. Here we review (1) the current knowledge of molecular mechanisms regulating local translation and the actin cytoskeleton state at an activated synapse, where they play a key role in the
formation of various sorts of synaptic plasticity and long-term memory, and (2) possible pathways of mechanical
stress intervention. The roles of the mTOR (mammalian target of rapamycin) signaling pathway; the RNA-binding
FMRP protein; the CYFIP1 protein, interacting with FMRP; the family of small GTPases; and the WAVE regulatory
complex in the regulation of translation initiation and actin cytoskeleton rearrangements in dendritic spines of the
activated synapse are discussed. Evidence is provided that chronic mechanical stress may result in aberrant activation of mTOR signaling and the WAVE regulatory complex via the YAP/TAZ system, the key sensor of mechanical
signals, and influence the associated pathways regulating the formation of F actin filaments and the dendritic spine
structure. These consequences may be a risk factor for various neurological conditions, including autistic spectrum
disorders and epileptic encephalopathy. In further consideration of the role of the local translation system in the
development of neuropsychic and neurodegenerative diseases, an original hypothesis was put forward that one
of the possible causes of synaptopathies is impaired proteome stability associated with mTOR hyperactivity and
formation of complex dynamic modes of de novo protein synthesis in response to synapse-stimulating factors,
including chronic mechanical stress.
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Affiliation(s)
- T M Khlebodarova
- Institute of Cytology and Genetics of Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia Kurchatov Genomic Center of the Institute of Cytology and Genetics of Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
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9
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Pirooznia SK, Rosenthal LS, Dawson VL, Dawson TM. Parkinson Disease: Translating Insights from Molecular Mechanisms to Neuroprotection. Pharmacol Rev 2021; 73:33-97. [PMID: 34663684 DOI: 10.1124/pharmrev.120.000189] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Parkinson disease (PD) used to be considered a nongenetic condition. However, the identification of several autosomal dominant and recessive mutations linked to monogenic PD has changed this view. Clinically manifest PD is then thought to occur through a complex interplay between genetic mutations, many of which have incomplete penetrance, and environmental factors, both neuroprotective and increasing susceptibility, which variably interact to reach a threshold over which PD becomes clinically manifested. Functional studies of PD gene products have identified many cellular and molecular pathways, providing crucial insights into the nature and causes of PD. PD originates from multiple causes and a range of pathogenic processes at play, ultimately culminating in nigral dopaminergic loss and motor dysfunction. An in-depth understanding of these complex and possibly convergent pathways will pave the way for therapeutic approaches to alleviate the disease symptoms and neuroprotective strategies to prevent disease manifestations. This review is aimed at providing a comprehensive understanding of advances made in PD research based on leveraging genetic insights into the pathogenesis of PD. It further discusses novel perspectives to facilitate identification of critical molecular pathways that are central to neurodegeneration that hold the potential to develop neuroprotective and/or neurorestorative therapeutic strategies for PD. SIGNIFICANCE STATEMENT: A comprehensive review of PD pathophysiology is provided on the complex interplay of genetic and environmental factors and biologic processes that contribute to PD pathogenesis. This knowledge identifies new targets that could be leveraged into disease-modifying therapies to prevent or slow neurodegeneration in PD.
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Affiliation(s)
- Sheila K Pirooznia
- Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering (S.K.P., V.L.D., T.M.D.), Departments of Neurology (S.K.P., L.S.R., V.L.D., T.M.D.), Departments of Physiology (V.L.D.), Solomon H. Snyder Department of Neuroscience (V.L.D., T.M.D.), Department of Pharmacology and Molecular Sciences (T.M.D.), Johns Hopkins University School of Medicine, Baltimore, Maryland; Adrienne Helis Malvin Medical Research Foundation, New Orleans, Louisiana (S.K.P., V.L.D., T.M.D.); and Diana Helis Henry Medical Research Foundation, New Orleans, Louisiana (S.K.P., V.L.D., T.M.D.)
| | - Liana S Rosenthal
- Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering (S.K.P., V.L.D., T.M.D.), Departments of Neurology (S.K.P., L.S.R., V.L.D., T.M.D.), Departments of Physiology (V.L.D.), Solomon H. Snyder Department of Neuroscience (V.L.D., T.M.D.), Department of Pharmacology and Molecular Sciences (T.M.D.), Johns Hopkins University School of Medicine, Baltimore, Maryland; Adrienne Helis Malvin Medical Research Foundation, New Orleans, Louisiana (S.K.P., V.L.D., T.M.D.); and Diana Helis Henry Medical Research Foundation, New Orleans, Louisiana (S.K.P., V.L.D., T.M.D.)
| | - Valina L Dawson
- Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering (S.K.P., V.L.D., T.M.D.), Departments of Neurology (S.K.P., L.S.R., V.L.D., T.M.D.), Departments of Physiology (V.L.D.), Solomon H. Snyder Department of Neuroscience (V.L.D., T.M.D.), Department of Pharmacology and Molecular Sciences (T.M.D.), Johns Hopkins University School of Medicine, Baltimore, Maryland; Adrienne Helis Malvin Medical Research Foundation, New Orleans, Louisiana (S.K.P., V.L.D., T.M.D.); and Diana Helis Henry Medical Research Foundation, New Orleans, Louisiana (S.K.P., V.L.D., T.M.D.)
| | - Ted M Dawson
- Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering (S.K.P., V.L.D., T.M.D.), Departments of Neurology (S.K.P., L.S.R., V.L.D., T.M.D.), Departments of Physiology (V.L.D.), Solomon H. Snyder Department of Neuroscience (V.L.D., T.M.D.), Department of Pharmacology and Molecular Sciences (T.M.D.), Johns Hopkins University School of Medicine, Baltimore, Maryland; Adrienne Helis Malvin Medical Research Foundation, New Orleans, Louisiana (S.K.P., V.L.D., T.M.D.); and Diana Helis Henry Medical Research Foundation, New Orleans, Louisiana (S.K.P., V.L.D., T.M.D.)
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10
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Fernandes HJR, Patikas N, Foskolou S, Field SF, Park JE, Byrne ML, Bassett AR, Metzakopian E. Single-Cell Transcriptomics of Parkinson's Disease Human In Vitro Models Reveals Dopamine Neuron-Specific Stress Responses. Cell Rep 2021; 33:108263. [PMID: 33053338 DOI: 10.1016/j.celrep.2020.108263] [Citation(s) in RCA: 59] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Revised: 05/29/2020] [Accepted: 09/22/2020] [Indexed: 12/12/2022] Open
Abstract
The advent of induced pluripotent stem cell (iPSC)-derived neurons has revolutionized Parkinson's disease (PD) research, but single-cell transcriptomic analysis suggests unresolved cellular heterogeneity within these models. Here, we perform the largest single-cell transcriptomic study of human iPSC-derived dopaminergic neurons to elucidate gene expression dynamics in response to cytotoxic and genetic stressors. We identify multiple neuronal subtypes with transcriptionally distinct profiles and differential sensitivity to stress, highlighting cellular heterogeneity in dopamine in vitro models. We validate this disease model by showing robust expression of PD GWAS genes and overlap with postmortem adult substantia nigra neurons. Importantly, stress signatures are ameliorated using felodipine, an FDA-approved drug. Using isogenic SNCA-A53T mutants, we find perturbations in glycolysis, cholesterol metabolism, synaptic signaling, and ubiquitin-proteasomal degradation. Overall, our study reveals cell type-specific perturbations in human dopamine neurons, which will further our understanding of PD and have implications for cell replacement therapies.
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Affiliation(s)
- Hugo J R Fernandes
- UK Dementia Research Institute, Department of Clinical Neurosciences, Cambridge Biomedical Campus, University of Cambridge, Cambridge, CB2 0AH, UK; Open Targets, Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SA, UK
| | - Nikolaos Patikas
- UK Dementia Research Institute, Department of Clinical Neurosciences, Cambridge Biomedical Campus, University of Cambridge, Cambridge, CB2 0AH, UK
| | - Stefanie Foskolou
- UK Dementia Research Institute, Department of Clinical Neurosciences, Cambridge Biomedical Campus, University of Cambridge, Cambridge, CB2 0AH, UK; Open Targets, Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SA, UK
| | - Sarah F Field
- UK Dementia Research Institute, Department of Clinical Neurosciences, Cambridge Biomedical Campus, University of Cambridge, Cambridge, CB2 0AH, UK
| | - Jong-Eun Park
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SA, UK; Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology, Daejeon, South Korea
| | - Meg L Byrne
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SA, UK
| | - Andrew R Bassett
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SA, UK
| | - Emmanouil Metzakopian
- UK Dementia Research Institute, Department of Clinical Neurosciences, Cambridge Biomedical Campus, University of Cambridge, Cambridge, CB2 0AH, UK.
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11
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Jishi A, Qi X, Miranda HC. Implications of mRNA translation dysregulation for neurological disorders. Semin Cell Dev Biol 2021; 114:11-19. [PMID: 34024497 PMCID: PMC8144541 DOI: 10.1016/j.semcdb.2020.09.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 08/30/2020] [Accepted: 09/08/2020] [Indexed: 02/07/2023]
Abstract
The translation of information encoded in the DNA into functional proteins is one of the tenets of cellular biology. Cell survival and function depend on the tightly controlled processes of transcription and translation. Growing evidence suggests that dysregulation in mRNA translation plays an important role in the pathogenesis of several neurodevelopmental diseases, such as autism spectrum disorder (ASD) and fragile X syndrome (FXS) as well as neurodegenerative disorders, such as Alzheimer's disease (AD), Parkinson's disease (PD) and amyotrophic lateral sclerosis (ALS). In this review, we provide an overview of mRNA translation and its modes of regulation that have been implicated in neurological disease.
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Affiliation(s)
- Aya Jishi
- Department of Physiology and Biophysics, School of Medicine, Case Western Reserve University, Cleveland, OH, USA
| | - Xin Qi
- Department of Physiology and Biophysics, School of Medicine, Case Western Reserve University, Cleveland, OH, USA
| | - Helen C Miranda
- Department of Genetics and Genome Sciences, School of Medicine, Case Western Reserve University, Cleveland, OH, USA; Department of Neurosciences, School of Medicine Case Western Reserve University, Cleveland, OH, USA.
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12
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Petyuk VA, Yu L, Olson HM, Yu F, Clair G, Qian WJ, Shulman JM, Bennett DA. Proteomic Profiling of the Substantia Nigra to Identify Determinants of Lewy Body Pathology and Dopaminergic Neuronal Loss. J Proteome Res 2021; 20:2266-2282. [PMID: 33900085 PMCID: PMC9190253 DOI: 10.1021/acs.jproteome.0c00747] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Proteinaceous aggregates containing α-synuclein protein called Lewy bodies in the substantia nigra is a hallmark of Parkinson's disease. The molecular mechanisms of Lewy body formation and associated neuronal loss remain largely unknown. To gain insights into proteins and pathways associated with Lewy body pathology, we performed quantitative profiling of the proteome. We analyzed substantia nigra tissue from 51 subjects arranged into three groups: cases with Lewy body pathology, Lewy body-negative controls with matching neuronal loss, and controls with no neuronal loss. Using a label-free liquid chromatography-tandem mass spectrometry (LC-MS/MS) approach, we characterized the proteome both in terms of protein abundances and peptide modifications. Statistical testing for differential abundance of the most abundant 2963 proteins, followed by pathway enrichment and Bayesian learning of the causal network structure, was performed to identify likely drivers of Lewy body formation and dopaminergic neuronal loss. The identified pathways include (1) Arp2/3 complex-mediated actin nucleation; (2) synaptic function; (3) poly(A) RNA binding; (4) basement membrane and endothelium; and (5) hydrogen peroxide metabolic process. According to the data, the endothelial/basement membrane pathway is tightly connected with both pathologies and likely to be one of the drivers of neuronal loss. The poly(A) RNA-binding proteins, including the ones relevant to other neurodegenerative disorders (e.g., TDP-43 and FUS), have a strong inverse correlation with Lewy bodies and may reflect an alternative mechanism of nigral neurodegeneration.
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Affiliation(s)
- Vladislav A Petyuk
- Biological Sciences Division, Pacific Northwest National Laboratory, P.O. Box 999, MSIN: K8-98, Richland, Washington 99352, United States
| | - Lei Yu
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, Illinois 60612, United States
- Department of Neurological Sciences, Rush University Medical Center, Chicago, Illinois 60612, United States
| | - Heather M Olson
- Environmental and Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - Fengchao Yu
- Department of Pathology, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Geremy Clair
- Biological Sciences Division, Pacific Northwest National Laboratory, P.O. Box 999, MSIN: K8-98, Richland, Washington 99352, United States
| | - Wei-Jun Qian
- Biological Sciences Division, Pacific Northwest National Laboratory, P.O. Box 999, MSIN: K8-98, Richland, Washington 99352, United States
| | - Joshua M Shulman
- Departments of Neurology, Molecular & Human Genetics, and Neuroscience, Baylor College of Medicine, Houston, Texas 77030, United States
- Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, Texas 77030, United States
| | - David A Bennett
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, Illinois 60612, United States
- Department of Neurological Sciences, Rush University Medical Center, Chicago, Illinois 60612, United States
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13
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Khlebodarova TM, Kogai VV, Likhoshvai VA. On the dynamical aspects of local translation at the activated synapse. BMC Bioinformatics 2020; 21:258. [PMID: 32921299 PMCID: PMC7488754 DOI: 10.1186/s12859-020-03597-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2020] [Accepted: 06/10/2020] [Indexed: 02/01/2023] Open
Abstract
Background The key role in the dynamic regulation of synaptic protein turnover belongs to the Fragile X Mental Retardation Protein, which regulates the efficiency of dendritic mRNA translation in response to stimulation of metabotropic glutamate receptors at excitatory synapses of the hippocampal pyramidal cells. Its activity is regulated via positive and negative regulatory loops that function in different time ranges, which is an absolute factor for the formation of chaotic regimes that lead to disrupted proteome stability. The indicated condition may cause a number of neuropsychiatric diseases, including autism and epilepsy. The present study is devoted to a theoretical analysis of the local translation system dynamic properties and identification of parameters affecting the chaotic potential of the system. Results A mathematical model that describes the maintenance of a specific pool of active receptors on the postsynaptic membrane via two mechanisms – de novo synthesis of receptor proteins and restoration of protein function during the recycling process – has been developed. Analysis of the model revealed that an increase in the values of the parameters describing the impact of protein recycling on the maintenance of a pool of active receptors in the membrane, duration of the signal transduction via the mammalian target of rapamycin pathway, influence of receptors on the translation activation, as well as reduction of the rate of synthesis and integration of de novo synthesized proteins into the postsynaptic membrane – contribute to the reduced complexity of the local translation system dynamic state. Formation of these patterns significantly depends on the complexity and non-linearity of the mechanisms of exposure of de novo synthesized receptors to the postsynaptic membrane, the correct evaluation of which is currently problematic. Conclusions The model predicts that an increase of “receptor recycling” and reduction of the rate of synthesis and integration of de novo synthesized proteins into the postsynaptic membrane contribute to the reduced complexity of the local translation system dynamic state. Herewith, stable stationary states occur much less frequently than cyclic states. It is possible that cyclical nature of functioning of the local translation system is its “normal” dynamic state.
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Affiliation(s)
- Tamara M Khlebodarova
- Department of Systems Biology, Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, 630090, Russia. .,Novosibirsk State University, Novosibirsk, 630090, Russia.
| | | | - Vitaly A Likhoshvai
- Department of Systems Biology, Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, 630090, Russia
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14
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Dynamic landscape of the local translation at activated synapses. Mol Psychiatry 2018; 23:107-114. [PMID: 29203851 PMCID: PMC5754473 DOI: 10.1038/mp.2017.245] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Accepted: 10/09/2017] [Indexed: 01/17/2023]
Abstract
The mammalian target of rapamycin (mTOR) signaling pathway is the central regulator of cap-dependent translation at the synapse. Disturbances in mTOR pathway have been associated with several neurological diseases, such as autism and epilepsy. RNA-binding protein FMRP, a negative regulator of translation initiation, is one of the key components of the local translation system. Activation and inactivation of FMRP occurs via phosphorylation by S6 kinase and dephosphorylation by PP2A phosphatase, respectively. S6 kinase and PP2A phosphatase are activated in response to mGluR receptor stimulation through different signaling pathways and at different rates. The dynamic aspects of this system are poorly understood. We developed a mathematical model of FMRP-dependent regulation of postsynaptic density (PSD) protein synthesis in response to mGluR receptor stimulation and conducted in silico experiments to study the regulatory circuit functioning. The modeling results revealed the possibility of generating oscillatory (cyclic and quasi-cyclic), chaotic and even hyperchaotic dynamics of postsynaptic protein synthesis as well as the presence of multiple attractors in a wide range of parameters of the local translation system. The results suggest that autistic disorders associated with mTOR pathway hyperactivation may be due to impaired proteome stability associated with the formation of complex dynamic regimes of PSD protein synthesis in response to stimulation of mGluR receptors on the postsynaptic membrane of excitatory synapses on pyramidal hippocampal cells.
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