1
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Dhawka L, Palfini V, Hambright E, Blanco I, Poon C, Kahl A, Resch U, Bhawal R, Benakis C, Balachandran V, Holder A, Zhang S, Iadecola C, Hochrainer K. Post-ischemic ubiquitination at the postsynaptic density reversibly influences the activity of ischemia-relevant kinases. Commun Biol 2024; 7:321. [PMID: 38480905 PMCID: PMC10937959 DOI: 10.1038/s42003-024-06009-8] [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: 08/21/2023] [Accepted: 03/04/2024] [Indexed: 03/17/2024] Open
Abstract
Ubiquitin modifications alter protein function and stability, thereby regulating cell homeostasis and viability, particularly under stress. Ischemic stroke induces protein ubiquitination at the ischemic periphery, wherein cells remain viable, however the identity of ubiquitinated proteins is unknown. Here, we employed a proteomics approach to identify these proteins in mice undergoing ischemic stroke. The data are available in a searchable web interface ( https://hochrainerlab.shinyapps.io/StrokeUbiOmics/ ). We detected increased ubiquitination of 198 proteins, many of which localize to the postsynaptic density (PSD) of glutamatergic neurons. Among these were proteins essential for maintaining PSD architecture, such as PSD95, as well as NMDA and AMPA receptor subunits. The largest enzymatic group at the PSD with elevated post-ischemic ubiquitination were kinases, such as CaMKII, PKC, Cdk5, and Pyk2, whose aberrant activities are well-known to contribute to post-ischemic neuronal death. Concurrent phospho-proteomics revealed altered PSD-associated phosphorylation patterns, indicative of modified kinase activities following stroke. PSD-located CaMKII, PKC, and Cdk5 activities were decreased while Pyk2 activity was increased after stroke. Removal of ubiquitin restored kinase activities to pre-stroke levels, identifying ubiquitination as the responsible molecular mechanism for post-ischemic kinase regulation. These findings unveil a previously unrecognized role of ubiquitination in the regulation of essential kinases involved in ischemic injury.
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Affiliation(s)
- Luvna Dhawka
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, USA
| | - Victoria Palfini
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, USA
| | - Emma Hambright
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, USA
| | - Ismary Blanco
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, USA
| | - Carrie Poon
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, USA
| | - Anja Kahl
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, USA
| | - Ulrike Resch
- Center for Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Ruchika Bhawal
- Institute of Biotechnology, Cornell University, Ithaca, NY, USA
| | - Corinne Benakis
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, USA
- Institute for Stroke and Dementia Research, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Vaishali Balachandran
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, USA
| | - Alana Holder
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, USA
| | - Sheng Zhang
- Institute of Biotechnology, Cornell University, Ithaca, NY, USA
| | - Costantino Iadecola
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, USA
| | - Karin Hochrainer
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, USA.
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2
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Johansson J, Lidéus S, Frykholm C, Gunnarsson C, Mihalic F, Gudmundsson S, Ekvall S, Molin AM, Pham M, Vihinen M, Lagerstedt-Robinson K, Nordgren A, Jemth P, Ameur A, Annerén G, Wilbe M, Bondeson ML. Gustavson syndrome is caused by an in-frame deletion in RBMX associated with potentially disturbed SH3 domain interactions. Eur J Hum Genet 2024; 32:333-341. [PMID: 37277488 PMCID: PMC10923852 DOI: 10.1038/s41431-023-01392-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2022] [Revised: 03/07/2023] [Accepted: 05/12/2023] [Indexed: 06/07/2023] Open
Abstract
RNA binding motif protein X-linked (RBMX) encodes the heterogeneous nuclear ribonucleoprotein G (hnRNP G) that regulates splicing, sister chromatid cohesion and genome stability. RBMX knock down experiments in various model organisms highlight the gene's importance for brain development. Deletion of the RGG/RG motif in hnRNP G has previously been associated with Shashi syndrome, however involvement of other hnRNP G domains in intellectual disability remain unknown. In the current study, we present the underlying genetic and molecular cause of Gustavson syndrome. Gustavson syndrome was first reported in 1993 in a large Swedish five-generation family presented with profound X-linked intellectual disability and an early death. Extensive genomic analyses of the family revealed hemizygosity for a novel in-frame deletion in RBMX in affected individuals (NM_002139.4; c.484_486del, p.(Pro162del)). Carrier females were asymptomatic and presented with skewed X-chromosome inactivation, indicating silencing of the pathogenic allele. Affected individuals presented minor phenotypic overlap with Shashi syndrome, indicating a different disease-causing mechanism. Investigation of the variant effect in a neuronal cell line (SH-SY5Y) revealed differentially expressed genes enriched for transcription factors involved in RNA polymerase II transcription. Prediction tools and a fluorescence polarization assay imply a novel SH3-binding motif of hnRNP G, and potentially a reduced affinity to SH3 domains caused by the deletion. In conclusion, we present a novel in-frame deletion in RBMX segregating with Gustavson syndrome, leading to disturbed RNA polymerase II transcription, and potentially reduced SH3 binding. The results indicate that disruption of different protein domains affects the severity of RBMX-associated intellectual disabilities.
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Affiliation(s)
- Josefin Johansson
- Department of Immunology, Genetics and Pathology, Biomedical Centre, Uppsala University, Uppsala, Sweden
| | - Sarah Lidéus
- Department of Immunology, Genetics and Pathology, Biomedical Centre, Uppsala University, Uppsala, Sweden
| | - Carina Frykholm
- Department of Immunology, Genetics and Pathology, Biomedical Centre, Uppsala University, Uppsala, Sweden
| | - Cecilia Gunnarsson
- Department of Clinical Genetics, and Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
- Centre for Rare Diseases in South East Region of Sweden, Linköping University, Linköping, Sweden
| | - Filip Mihalic
- Department of Medical Biochemistry and Microbiology, Uppsala University, Box 582, Husargatan 3, 751 23, Uppsala, Sweden
| | - Sanna Gudmundsson
- Department of Immunology, Genetics and Pathology, Biomedical Centre, Uppsala University, Uppsala, Sweden
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Division of Genetics and Genomics, Boston Children's Hospital, Boston, MA, USA
| | - Sara Ekvall
- Department of Immunology, Genetics and Pathology, Biomedical Centre, Uppsala University, Uppsala, Sweden
| | - Anna-Maja Molin
- Department of Immunology, Genetics and Pathology, Biomedical Centre, Uppsala University, Uppsala, Sweden
| | - Mai Pham
- Department of Immunology, Genetics and Pathology, Biomedical Centre, Uppsala University, Uppsala, Sweden
| | - Mauno Vihinen
- Department of Experimental Medical Science, BMC B13, Lund University, SE-22 184, Lund, Sweden
| | - Kristina Lagerstedt-Robinson
- Clinical Genetics, Karolinska University Hospital, Solna, Sweden
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden
| | - Ann Nordgren
- Clinical Genetics, Karolinska University Hospital, Solna, Sweden
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden
- Department of Clinical Genetics and Genomics, Sahlgrenska University Hospital, Gothenburg, Sweden
- Institute of Biomedicine, Department of Laboratory Medicine, University of Gothenburg, Gothenburg, Sweden
| | - Per Jemth
- Department of Medical Biochemistry and Microbiology, Uppsala University, Box 582, Husargatan 3, 751 23, Uppsala, Sweden
| | - Adam Ameur
- Department of Immunology, Genetics and Pathology, Biomedical Centre, Uppsala University, Uppsala, Sweden
| | - Göran Annerén
- Department of Immunology, Genetics and Pathology, Biomedical Centre, Uppsala University, Uppsala, Sweden
| | - Maria Wilbe
- Department of Immunology, Genetics and Pathology, Biomedical Centre, Uppsala University, Uppsala, Sweden
| | - Marie-Louise Bondeson
- Department of Immunology, Genetics and Pathology, Biomedical Centre, Uppsala University, Uppsala, Sweden.
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3
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Dhawka L, Palfini V, Hambright E, Blanco I, Poon C, Kahl A, Resch U, Bhawal R, Benakis C, Balachandran V, Zhang S, Iadecola C, Hochrainer K. Post-ischemic ubiquitination at the postsynaptic density reversibly influences the activity of ischemia-relevant kinases. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.21.552860. [PMID: 37662420 PMCID: PMC10473581 DOI: 10.1101/2023.08.21.552860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/05/2023]
Abstract
Ubiquitin modifications alter protein function and stability, thereby regulating cell homeostasis and viability, particularly under stress. Ischemic stroke induces protein ubiquitination at the ischemic periphery, wherein cells remain viable, however the identity of ubiquitinated proteins is unknown. Here, we employed a proteomics approach to identify these proteins in mice undergoing ischemic stroke. The data are available in a searchable web interface ( https://hochrainerlab.shinyapps.io/StrokeUbiOmics/ ). We detected increased ubiquitination of 198 proteins, many of which localize to the postsynaptic density (PSD) of glutamatergic neurons. Among these were proteins essential for maintaining PSD architecture, such as PSD95, as well as NMDA and AMPA receptor subunits. The largest enzymatic group at the PSD with elevated post-ischemic ubiquitination were kinases, such as CaMKII, PKC, Cdk5, and Pyk2, whose aberrant activities are well-known to contribute to post-ischemic neuronal death. Concurrent phospho-proteomics revealed altered PSD-associated phosphorylation patterns, indicative of modified kinase activities following stroke. PSD-located CaMKII, PKC, and Cdk5 activities were decreased while Pyk2 activity was increased after stroke. Removal of ubiquitin restored kinase activities to pre-stroke levels, identifying ubiquitination as the responsible molecular mechanism for post-ischemic kinase regulation. These findings unveil a previously unrecognized role of ubiquitination in the regulation of essential kinases involved in ischemic injury.
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Carbonell AU, Freire-Cobo C, Deyneko IV, Dobariya S, Erdjument-Bromage H, Clipperton-Allen AE, Page DT, Neubert TA, Jordan BA. Comparing synaptic proteomes across five mouse models for autism reveals converging molecular similarities including deficits in oxidative phosphorylation and Rho GTPase signaling. Front Aging Neurosci 2023; 15:1152562. [PMID: 37255534 PMCID: PMC10225639 DOI: 10.3389/fnagi.2023.1152562] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Accepted: 04/17/2023] [Indexed: 06/01/2023] Open
Abstract
Specific and effective treatments for autism spectrum disorder (ASD) are lacking due to a poor understanding of disease mechanisms. Here we test the idea that similarities between diverse ASD mouse models are caused by deficits in common molecular pathways at neuronal synapses. To do this, we leverage the availability of multiple genetic models of ASD that exhibit shared synaptic and behavioral deficits and use quantitative mass spectrometry with isobaric tandem mass tagging (TMT) to compare their hippocampal synaptic proteomes. Comparative analyses of mouse models for Fragile X syndrome (Fmr1 knockout), cortical dysplasia focal epilepsy syndrome (Cntnap2 knockout), PTEN hamartoma tumor syndrome (Pten haploinsufficiency), ANKS1B syndrome (Anks1b haploinsufficiency), and idiopathic autism (BTBR+) revealed several common altered cellular and molecular pathways at the synapse, including changes in oxidative phosphorylation, and Rho family small GTPase signaling. Functional validation of one of these aberrant pathways, Rac1 signaling, confirms that the ANKS1B model displays altered Rac1 activity counter to that observed in other models, as predicted by the bioinformatic analyses. Overall similarity analyses reveal clusters of synaptic profiles, which may form the basis for molecular subtypes that explain genetic heterogeneity in ASD despite a common clinical diagnosis. Our results suggest that ASD-linked susceptibility genes ultimately converge on common signaling pathways regulating synaptic function and propose that these points of convergence are key to understanding the pathogenesis of this disorder.
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Affiliation(s)
- Abigail U. Carbonell
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY, United States
| | - Carmen Freire-Cobo
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY, United States
| | - Ilana V. Deyneko
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY, United States
| | - Saunil Dobariya
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY, United States
| | - Hediye Erdjument-Bromage
- Department of Neuroscience and Physiology, New York University Grossman School of Medicine, New York, NY, United States
| | - Amy E. Clipperton-Allen
- Department of Neuroscience, The Scripps Research Institute Florida, Jupiter, FL, United States
| | - Damon T. Page
- Department of Neuroscience, The Scripps Research Institute Florida, Jupiter, FL, United States
| | - Thomas A. Neubert
- Department of Neuroscience and Physiology, New York University Grossman School of Medicine, New York, NY, United States
| | - Bryen A. Jordan
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY, United States
- Department of Psychiatry and Behavioral Sciences, Albert Einstein College of Medicine, Bronx, NY, United States
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5
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Kasai H, Ucar H, Morimoto Y, Eto F, Okazaki H. Mechanical transmission at spine synapses: Short-term potentiation and working memory. Curr Opin Neurobiol 2023; 80:102706. [PMID: 36931116 DOI: 10.1016/j.conb.2023.102706] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Revised: 11/17/2022] [Accepted: 02/15/2023] [Indexed: 03/17/2023]
Abstract
Do dendritic spines, which comprise the postsynaptic component of most excitatory synapses, exist only for their structural dynamics, receptor trafficking, and chemical and electrical compartmentation? The answer is no. Simultaneous investigation of both spine and presynaptic terminals has recently revealed a novel feature of spine synapses. Spine enlargement pushes the presynaptic terminals with muscle-like force and augments the evoked glutamate release for up to 20 min. We now summarize the evidence that such mechanical transmission shares critical features in common with short-term potentiation (STP) and may represent the cellular basis of short-term and working memory. Thus, spine synapses produce the force of learning to leave structural traces for both short and long-term memories.
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Affiliation(s)
- Haruo Kasai
- International Research Center for Neurointelligence (WPI-IRCN), UTIAS, The University of Tokyo, Bunkyo-ku, Tokyo, Japan; Laboratory of Structural Physiology, Center for Disease Biology and Integrative Medicine, Faculty of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo, Japan.
| | - Hasan Ucar
- International Research Center for Neurointelligence (WPI-IRCN), UTIAS, The University of Tokyo, Bunkyo-ku, Tokyo, Japan; Laboratory of Structural Physiology, Center for Disease Biology and Integrative Medicine, Faculty of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Yuichi Morimoto
- International Research Center for Neurointelligence (WPI-IRCN), UTIAS, The University of Tokyo, Bunkyo-ku, Tokyo, Japan; Laboratory of Structural Physiology, Center for Disease Biology and Integrative Medicine, Faculty of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Fumihiro Eto
- International Research Center for Neurointelligence (WPI-IRCN), UTIAS, The University of Tokyo, Bunkyo-ku, Tokyo, Japan; Laboratory of Structural Physiology, Center for Disease Biology and Integrative Medicine, Faculty of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Hitoshi Okazaki
- International Research Center for Neurointelligence (WPI-IRCN), UTIAS, The University of Tokyo, Bunkyo-ku, Tokyo, Japan; Laboratory of Structural Physiology, Center for Disease Biology and Integrative Medicine, Faculty of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
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6
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Zhang G, Deinhardt K, Neubert TA. Stable Isotope Labeling by Amino Acids and Bioorthogonal Noncanonical Amino Acid Tagging in Cultured Primary Neurons. Methods Mol Biol 2023; 2603:163-171. [PMID: 36370278 PMCID: PMC10150910 DOI: 10.1007/978-1-0716-2863-8_13] [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: 11/13/2022]
Abstract
Cultured primary neurons are a well-established model for the study of neuronal function. Conventional stable isotope labeling with amino acids in cell culture (SILAC) requires nearly complete metabolic labeling of proteins and therefore is difficult to apply to cultured primary neurons, which do not divide in culture. In a multiplex SILAC strategy, two different sets of heavy amino acids are used for labeling cells for the different experimental conditions. This allows for straightforward SILAC quantitation using partially labeled cells because the two cell populations are always equally labeled. When combined with bioorthogonal noncanonical amino acid tagging (BONCAT), it allows for comparative proteomic analysis of de novo protein synthesis. Here we describe protocols that utilize the multiplex SILAC labeling strategy for primary cultured neurons to study steady-state and nascent proteomes.
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Affiliation(s)
- Guoan Zhang
- Proteomics and Metabolomics Core Facility, Weill Cornell Medicine, New York, NY, USA
| | - Katrin Deinhardt
- Institute for Life Sciences and Centre for Biological Sciences, University of Southampton, Southampton, UK
| | - Thomas A Neubert
- Department of Cell Biology and Kimmel Center for Molecular Medicine at the Skirball Institute, New York University Grossman School of Medicine, New York, NY, USA.
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7
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Di Liegro CM, Schiera G, Schirò G, Di Liegro I. RNA-Binding Proteins as Epigenetic Regulators of Brain Functions and Their Involvement in Neurodegeneration. Int J Mol Sci 2022; 23:ijms232314622. [PMID: 36498959 PMCID: PMC9739182 DOI: 10.3390/ijms232314622] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Revised: 11/18/2022] [Accepted: 11/22/2022] [Indexed: 11/25/2022] Open
Abstract
A central aspect of nervous system development and function is the post-transcriptional regulation of mRNA fate, which implies time- and site-dependent translation, in response to cues originating from cell-to-cell crosstalk. Such events are fundamental for the establishment of brain cell asymmetry, as well as of long-lasting modifications of synapses (long-term potentiation: LTP), responsible for learning, memory, and higher cognitive functions. Post-transcriptional regulation is in turn dependent on RNA-binding proteins that, by recognizing and binding brief RNA sequences, base modifications, or secondary/tertiary structures, are able to control maturation, localization, stability, and translation of the transcripts. Notably, most RBPs contain intrinsically disordered regions (IDRs) that are thought to be involved in the formation of membrane-less structures, probably due to liquid-liquid phase separation (LLPS). Such structures are evidenced as a variety of granules that contain proteins and different classes of RNAs. The other side of the peculiar properties of IDRs is, however, that, under altered cellular conditions, they are also prone to form aggregates, as observed in neurodegeneration. Interestingly, RBPs, as part of both normal and aggregated complexes, are also able to enter extracellular vesicles (EVs), and in doing so, they can also reach cells other than those that produced them.
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Affiliation(s)
- Carlo Maria Di Liegro
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (Dipartimento di Scienze e Tecnologie Biologiche, Chimiche e Farmaceutiche) (STEBICEF), University of Palermo, 90128 Palermo, Italy
| | - Gabriella Schiera
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (Dipartimento di Scienze e Tecnologie Biologiche, Chimiche e Farmaceutiche) (STEBICEF), University of Palermo, 90128 Palermo, Italy
| | - Giuseppe Schirò
- Department of Biomedicine, Neurosciences and Advanced Diagnostics (Dipartimento di Biomedicina, Neuroscienze e Diagnostica Avanzata) (Bi.N.D.), University of Palermo, 90127 Palermo, Italy
| | - Italia Di Liegro
- Department of Biomedicine, Neurosciences and Advanced Diagnostics (Dipartimento di Biomedicina, Neuroscienze e Diagnostica Avanzata) (Bi.N.D.), University of Palermo, 90127 Palermo, Italy
- Correspondence: ; Tel.: +39-091-238-97 (ext. 415/446)
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8
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Dastidar SG, Nair D. A Ribosomal Perspective on Neuronal Local Protein Synthesis. Front Mol Neurosci 2022; 15:823135. [PMID: 35283723 PMCID: PMC8904363 DOI: 10.3389/fnmol.2022.823135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Accepted: 01/17/2022] [Indexed: 11/15/2022] Open
Abstract
Continued mRNA translation and protein production are critical for various neuronal functions. In addition to the precise sorting of proteins from cell soma to distant locations, protein synthesis allows a dynamic remodeling of the local proteome in a spatially variable manner. This spatial heterogeneity of protein synthesis is shaped by several factors such as injury, guidance cues, developmental cues, neuromodulators, and synaptic activity. In matured neurons, thousands of synapses are non-uniformly distributed throughout the dendritic arbor. At any given moment, the activity of individual synapses varies over a wide range, giving rise to the variability in protein synthesis. While past studies have primarily focused on the translation factors or the identity of translated mRNAs to explain the source of this variation, the role of ribosomes in this regard continues to remain unclear. Here, we discuss how several stochastic mechanisms modulate ribosomal functions, contributing to the variability in neuronal protein expression. Also, we point out several underexplored factors such as local ion concentration, availability of tRNA or ATP during translation, and molecular composition and organization of a compartment that can influence protein synthesis and its variability in neurons.
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9
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Notaro A, Messina A, La Bella V. A Deletion of the Nuclear Localization Signal Domain in the Fus Protein Induces Stable Post-stress Cytoplasmic Inclusions in SH-SY5Y Cells. Front Neurosci 2022; 15:759659. [PMID: 35002600 PMCID: PMC8733393 DOI: 10.3389/fnins.2021.759659] [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: 08/16/2021] [Accepted: 12/07/2021] [Indexed: 12/28/2022] Open
Abstract
Mutations in Fused-in-Sarcoma (FUS) gene involving the nuclear localization signal (NLS) domain lead to juvenile-onset Amyotrophic Lateral Sclerosis (ALS). The mutant protein mislocalizes to the cytoplasm, incorporating it into Stress Granules (SG). Whether SGs are the first step to the formation of stable FUS-containing aggregates is still unclear. In this work, we used acute and chronic stress paradigms to study the SG dynamics in a human SH-SY5Y neuroblastoma cell line carrying a deletion of the NLS domain of the FUS protein (homozygous: ΔNLS–/–; heterozygous: ΔNLS+/–). Wild-type (WT) cells served as controls. We evaluated the subcellular localization of the mutant protein through immunoblot and immunofluorescence, in basal conditions and after acute stress and chronic stress with sodium arsenite (NaAsO2). Cells were monitored for up to 24 h after rescue. FUS was expressed in both nucleus and cytoplasm in the ΔNLS+/– cells, whereas it was primarily cytoplasmic in the ΔNLS–/–. Acute NaAsO2 exposure induced SGs: at rescue,>90% of ΔNLS cells showed abundant FUS-containing if compared to less than 5% of the WT cells. The proportion of FUS-positive SGs remained 15–20% at 24 h in mutant cells. Cycloheximide did not abolish the long-lasting SGs in mutant cells. Chronic exposure to NaAsO2 did not induce significant SGs formation. A wealth of research has demonstrated that ALS-associated FUS mutations at the C-terminus facilitate the incorporation of the mutant protein into SGs. We have shown here that mutant FUS-containing SGs tend to fail to dissolve after stress, facilitating a liquid-to-solid phase transition. The FUS-containing inclusions seen in the dying motor neurons might therefore directly derive from SGs. This might represent an attractive target for future innovative therapies.
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Affiliation(s)
- Antonietta Notaro
- ALS Clinical Research Center and Laboratory of Neurochemistry, Department of Biomedicine, Neuroscience and Advances Diagnostics, University of Palermo, Palermo, Italy
| | - Antonella Messina
- ALS Clinical Research Center and Laboratory of Neurochemistry, Department of Biomedicine, Neuroscience and Advances Diagnostics, University of Palermo, Palermo, Italy
| | - Vincenzo La Bella
- ALS Clinical Research Center and Laboratory of Neurochemistry, Department of Biomedicine, Neuroscience and Advances Diagnostics, University of Palermo, Palermo, Italy
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10
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Lin YH, Wu H, Jia B, Zhang M, Chan HS. Assembly of model postsynaptic densities involves interactions auxiliary to stoichiometric binding. Biophys J 2022; 121:157-171. [PMID: 34637756 PMCID: PMC8758407 DOI: 10.1016/j.bpj.2021.10.008] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2021] [Revised: 09/29/2021] [Accepted: 10/06/2021] [Indexed: 01/07/2023] Open
Abstract
The assembly of functional biomolecular condensates often involves liquid-liquid phase separation (LLPS) of proteins with multiple modular domains, which can be folded or conformationally disordered to various degrees. To understand the LLPS-driving domain-domain interactions, a fundamental question is how readily the interactions in the condensed phase can be inferred from interdomain interactions in dilute solutions. In particular, are the interactions leading to LLPS exclusively those underlying the formation of discrete interdomain complexes in homogeneous solutions? We address this question by developing a mean-field LLPS theory of two stoichiometrically constrained solute species. The theory is applied to the neuronal proteins SynGAP and PSD-95, whose complex coacervate serves as a rudimentary model for neuronal postsynaptic densities (PSDs). The predicted phase behaviors are compared with experiments. Previously, a three SynGAP/two PSD-95 ratio was determined for SynGAP/PSD-95 complexes in dilute solutions. However, when this 3:2 stoichiometry is uniformly imposed in our theory encompassing both dilute and condensed phases, the tie-line pattern of the predicted SynGAP/PSD-95 phase diagram differs drastically from that obtained experimentally. In contrast, theories embodying alternate scenarios postulating auxiliary SynGAP-PSD-95 as well as SynGAP-SynGAP and PSD-95-PSD-95 interactions, in addition to those responsible for stoichiometric SynGAP/PSD-95 complexes, produce tie-line patterns consistent with experiment. Hence, our combined theoretical-experimental analysis indicates that weaker interactions or higher-order complexes beyond the 3:2 stoichiometry, but not yet documented, are involved in the formation of SynGAP/PSD-95 condensates, imploring future efforts to ascertain the nature of these auxiliary interactions in PSD-like LLPS and underscoring a likely general synergy between stoichiometric, structurally specific binding and stochastic, multivalent "fuzzy" interactions in the assembly of functional biomolecular condensates.
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Affiliation(s)
- Yi-Hsuan Lin
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada,Molecular Medicine, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Haowei Wu
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
| | - Bowen Jia
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
| | - Mingjie Zhang
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China,School of Life Sciences, Southern University of Science and Technology, Shenzhen, China,Corresponding author
| | - Hue Sun Chan
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada,Corresponding author
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11
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Abstract
Assembly of intermediate filaments (IFs) is reliant upon amino-terminal head domains. These head domains are of low sequence complexity and are assumed to function in the absence of structural order. Herein, we provide evidence that the head domains of the desmin and neurofilament light (NFL) IF proteins self-associate via the formation of labile but structurally specific cross-β interaction. Disease-causing mutations in the head domains of both proteins cause enhanced cross-β interactions. By assembling desmin and NFL IFs bearing isotopically labeled head domains, we provide evidence of structural order in properly assembled biological filaments. We propose that these observations on IF head domains may be instructive to the function of low complexity domains operative in other aspects of cell biology. Low complexity (LC) head domains 92 and 108 residues in length are, respectively, required for assembly of neurofilament light (NFL) and desmin intermediate filaments (IFs). As studied in isolation, these IF head domains interconvert between states of conformational disorder and labile, β-strand–enriched polymers. Solid-state NMR (ss-NMR) spectroscopic studies of NFL and desmin head domain polymers reveal spectral patterns consistent with structural order. A combination of intein chemistry and segmental isotope labeling allowed preparation of fully assembled NFL and desmin IFs that could also be studied by ss-NMR. Assembled IFs revealed spectra overlapping with those observed for β-strand–enriched polymers formed from the isolated NFL and desmin head domains. Phosphorylation and disease-causing mutations reciprocally alter NFL and desmin head domain self-association yet commonly impede IF assembly. These observations show how facultative structural assembly of LC domains via labile, β-strand–enriched self-interactions may broadly influence cell morphology.
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12
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Deletion of RBMX RGG/RG motif in Shashi-XLID syndrome leads to aberrant p53 activation and neuronal differentiation defects. Cell Rep 2021; 36:109337. [PMID: 34260915 DOI: 10.1016/j.celrep.2021.109337] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 04/29/2021] [Accepted: 06/11/2021] [Indexed: 01/01/2023] Open
Abstract
RNA-binding proteins play important roles in X-linked intellectual disability (XLID). In this study, we investigate the contribution of the XLID-associated RBMX in neuronal differentiation. We show that RBMX-depleted cells exhibit aberrant activation of the p53 pathway. Moreover, we identify that the RBMX RGG/RG motif is methylated by protein arginine methyltransferase 5 (PRMT5), and this regulates assembly with the SRSF1 splicing factor into higher-order complexes. Depletion of RBMX or disruption of the RBMX/SRSF1 complex in PRMT5-depleted cells reduces SRSF1 binding to the MDM4 precursor (pre-)mRNA, leading to exon 6 exclusion and lower MDM4 protein levels. Transcriptomic analysis of isogenic Shashi-XLID human-induced pluripotent stem cells (hiPSCs) generated using CRISPR-Cas9 reveals a dysregulation of MDM4 splicing and aberrant p53 upregulation. Shashi-XLID neural progenitor cells (NPCs) display differentiation and morphological abnormalities accompanied with excessive apoptosis. Our findings identify RBMX as a regulator of SRSF1 and the p53 pathway, suggesting that the loss of function of the RBMX RGG/RG motif is the cause of Shashi-XLID syndrome.
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13
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Chemical Stimulation of Rodent and Human Cortical Synaptosomes: Implications in Neurodegeneration. Cells 2021; 10:cells10051174. [PMID: 34065927 PMCID: PMC8151714 DOI: 10.3390/cells10051174] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 04/29/2021] [Accepted: 05/09/2021] [Indexed: 12/14/2022] Open
Abstract
Synaptic plasticity events, including long-term potentiation (LTP), are often regarded as correlates of brain functions of memory and cognition. One of the central players in these plasticity-related phenomena is the α-amino-3-hydroxy-5-methylisoxazole-4-propionate receptor (AMPAR). Increased levels of AMPARs on postsynaptic membranes thus constitute a biochemical measure of LTP. Isolated synaptic terminals (synaptosomes) are an excellent ex vivo tool to monitor synaptic physiology in healthy and diseased brains, particularly in human research. We herein describe three protocols for chemically-induced LTP (cLTP) in synaptosomes from both rodent and human brain tissues. Two of these chemical stimulation protocols are described for the first time in synaptosomes. A pharmacological block of synaptosomal actin dynamics confirmed the efficiency of the cLTP protocols. Furthermore, the study prototypically evaluated the deficiency of cLTP in cortical synaptosomes obtained from human cases of early-onset Alzheimer’s disease (EOAD) and frontotemporal lobar degeneration (FLTD), as well as an animal model that mimics FLTD.
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14
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Harley J, Clarke BE, Patani R. The Interplay of RNA Binding Proteins, Oxidative Stress and Mitochondrial Dysfunction in ALS. Antioxidants (Basel) 2021; 10:antiox10040552. [PMID: 33918215 PMCID: PMC8066094 DOI: 10.3390/antiox10040552] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 03/26/2021] [Accepted: 03/31/2021] [Indexed: 12/12/2022] Open
Abstract
RNA binding proteins fulfil a wide number of roles in gene expression. Multiple mechanisms of RNA binding protein dysregulation have been implicated in the pathomechanisms of several neurodegenerative diseases including amyotrophic lateral sclerosis (ALS). Oxidative stress and mitochondrial dysfunction also play important roles in these diseases. In this review, we highlight the mechanistic interplay between RNA binding protein dysregulation, oxidative stress and mitochondrial dysfunction in ALS. We also discuss different potential therapeutic strategies targeting these pathways.
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Affiliation(s)
- Jasmine Harley
- Department of Neuromuscular Diseases, Queen Square Institute of Neurology, University College London, London WC1N 3BG, UK;
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Benjamin E. Clarke
- Department of Neuromuscular Diseases, Queen Square Institute of Neurology, University College London, London WC1N 3BG, UK;
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
- Correspondence: (B.E.C.); (R.P.)
| | - Rickie Patani
- Department of Neuromuscular Diseases, Queen Square Institute of Neurology, University College London, London WC1N 3BG, UK;
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
- National Hospital for Neurology and Neurosurgery, University College London NHS, London WC1N 3BG, UK
- Correspondence: (B.E.C.); (R.P.)
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15
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Fultz EK, Coelho MA, Lieberman D, Jimenez-Chavez CL, Bryant CD, Szumlinski KK. Hnrnph1 is a novel regulator of alcohol reward. Drug Alcohol Depend 2021; 220:108518. [PMID: 33454624 PMCID: PMC7899125 DOI: 10.1016/j.drugalcdep.2021.108518] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 12/09/2020] [Accepted: 12/22/2020] [Indexed: 02/08/2023]
Abstract
BACKGROUND Hnrnph1 is a validated quantitative trait gene for methamphetamine behavioral sensitivity that encodes for heterogeneous nuclear ribonucleoprotein H1 (hnRNP H1). This RNA-binding protein is involved in all stages of RNA metabolism that impacts mesocorticolimbic dopamine neurotransmission to influence addiction-related behavior. METHODS We characterized the alcohol behavioral phenotypes of mice heterozygous for a deletion in the first coding exon of Hnrnph1 (Hnrnph1+/-). We examined alcohol intake under both continuous- and limited-access procedures, as well as alcohol-induced place-conditioning. Follow-up studies examined genotypic differences in the psychomotor-activating and sedative-hypnotic effects of acute and repeated alcohol, and a behavioral test battery was employed to determine the effects of Hnrnph1 deletion on the manifestation of negative affect during alcohol withdrawal. RESULTS Relative to wild-type (WT) controls, Hnrnph1+/- males exhibited blunted intake of high alcohol concentrations under both drinking procedures. Hnrnph1 deletion did not impact the conditioned rewarding properties of low-dose alcohol, but reversed the conditioned place-aversion elicited by higher alcohol doses (2 and 4 g/kg), with more robust effects in male versus female mice. No genotypic differences were observed for alcohol-induced locomotor activity. Hnrnph1+/- mice exhibited a modest increase in sensitivity to alcohol's sedative-hypnotic effects, but did not differ from WT mice with regard to tolerance to alcohol's sedative-hypnotic effects or alcohol metabolism, Inconsistent effects of Hnrnph1 deletion were observed in models for withdrawal-induced negative affect. CONCLUSIONS These data identify Hnrnph1 as a novel, male-selective, driver of alcohol consumption and high-dose alcohol aversion that is potentially relevant to the neurobiology of alcohol abuse and alcoholism.
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Affiliation(s)
- Elissa K Fultz
- Department of Psychological Brain Sciences, University of California, Santa Barbara, United States
| | - Michal A Coelho
- Department of Psychological Brain Sciences, University of California, Santa Barbara, United States
| | - Dylan Lieberman
- Department of Psychological Brain Sciences, University of California, Santa Barbara, United States
| | | | - Camron D Bryant
- Laboratory of Addiction Genetics, Department of Pharmacology and Experimental Therapeutics and Psychiatry, Boston University School of Medicine, United States
| | - Karen K Szumlinski
- Department of Psychological Brain Sciences, University of California, Santa Barbara, United States; Department of Molecular, Developmental and Cellular Biology and the Neuroscience Research Institute, University of California, Santa Barbara, United States.
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16
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Patel PD, Stafflinger JE, Marwitz JH, Niemeier JP, Ottens AK. Secreted Peptides for Diagnostic Trajectory Assessments in Brain Injury Rehabilitation. Neurorehabil Neural Repair 2020; 35:169-184. [PMID: 33331223 DOI: 10.1177/1545968320975428] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
BACKGROUND Rehabilitation following traumatic brain injury (TBI) significantly improves outcomes; yet TBI heterogeneity raises the need for molecular evidence of brain recovery processes to better track patient progress, evaluate therapeutic efficacy, and provide prognostication. OBJECTIVE Here, we assessed whether the trajectory of TBI-responsive peptides secreted into urine can produce a predictive model of functional recovery during TBI rehabilitation. METHODS The multivariate urinary peptidome of 12 individuals with TBI was examined using quantitative peptidomics. Measures were assessed upon admission and discharge from inpatient rehabilitation. A combination of Pavlidis template matching and partial least-squares discriminant analysis was used to build models on Disability Rating Scale (DRS) and Functional Independence Measure (FIM) scores, with participants bifurcated into more or less functional improvement groups. RESULTS The produced models exhibited high sensitivity and specificity with the area under the receiver operator curve being 0.99 for DRS- and 0.95 for FIM-based models using the top 20 discriminant peptides. Predictive ability for each model was assessed using robust leave-one-out cross-validation with Q2 statistics of 0.64 (P = .00012) and 0.62 (P = .011) for DRS- and FIM-based models, respectively, both with a high predictive accuracy of 0.875. Identified peptides that discriminated improved functional recovery reflected heightened neuroplasticity and synaptic refinement and diminished cell death and neuroinflammation, consistent with postacute TBI pathobiology. CONCLUSIONS Produced models of urine-based peptide measures reflective of ongoing recovery pathobiology can inform on rehabilitation progress after TBI, warranting further study to assess refined stratification across a larger population and efficacy in assessing therapeutic interventions.
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Affiliation(s)
- Parantap D Patel
- Virginia Commonwealth University, School of Medicine, Richmond, VA, USA
| | | | | | - Janet P Niemeier
- Virginia Commonwealth University, School of Medicine, Richmond, VA, USA
| | - Andrew K Ottens
- Virginia Commonwealth University, School of Medicine, Richmond, VA, USA
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17
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Bryant CD, Healy AF, Ruan QT, Coehlo MA, Lustig E, Yazdani N, Luttik KP, Tran T, Swancy I, Brewin LW, Chen MM, Szumlinski KK. Sex‐dependent effects of an
Hnrnph1
mutation on fentanyl addiction‐relevant behaviors but not antinociception in mice. GENES BRAIN AND BEHAVIOR 2020; 20:e12711. [DOI: 10.1111/gbb.12711] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 11/01/2020] [Accepted: 11/02/2020] [Indexed: 01/01/2023]
Affiliation(s)
- Camron D. Bryant
- Laboratory of Addiction Genetics, Department of Pharmacology and Experimental Therapeutics and Psychiatry Boston University School of Medicine Boston Massachusetts USA
| | - Aidan F. Healy
- Department of Psychological and Brain Sciences University of California Santa Barbara California USA
| | - Qiu T. Ruan
- Laboratory of Addiction Genetics, Department of Pharmacology and Experimental Therapeutics and Psychiatry Boston University School of Medicine Boston Massachusetts USA
- T32 Biomolecular Pharmacology Ph.D. Program Boston University School of Medicine Boston Massachusetts USA
- Transformative Training Program in Addiction Science Boston University Boston Massachusetts USA
| | - Michal A. Coehlo
- Department of Psychological and Brain Sciences University of California Santa Barbara California USA
| | - Elijah Lustig
- Department of Psychological and Brain Sciences University of California Santa Barbara California USA
| | - Neema Yazdani
- Laboratory of Addiction Genetics, Department of Pharmacology and Experimental Therapeutics and Psychiatry Boston University School of Medicine Boston Massachusetts USA
- T32 Biomolecular Pharmacology Ph.D. Program Boston University School of Medicine Boston Massachusetts USA
- Transformative Training Program in Addiction Science Boston University Boston Massachusetts USA
| | - Kimberly P. Luttik
- Laboratory of Addiction Genetics, Department of Pharmacology and Experimental Therapeutics and Psychiatry Boston University School of Medicine Boston Massachusetts USA
- Undergraduate Research Opportunity Program (UROP) Boston University Boston Massachusetts USA
| | - Tori Tran
- Department of Psychological and Brain Sciences University of California Santa Barbara California USA
| | - Isaiah Swancy
- Department of Psychological and Brain Sciences University of California Santa Barbara California USA
| | - Lindsey W. Brewin
- Department of Psychological and Brain Sciences University of California Santa Barbara California USA
| | - Melanie M. Chen
- Laboratory of Addiction Genetics, Department of Pharmacology and Experimental Therapeutics and Psychiatry Boston University School of Medicine Boston Massachusetts USA
| | - Karen K. Szumlinski
- Department of Psychological and Brain Sciences University of California Santa Barbara California USA
- Department of Molecular, Developmental and Cellular Biology and the Neuroscience Research Institute University of California Santa Barbara California USA
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18
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Jung Y, Seo JY, Ryu HG, Kim DY, Lee KH, Kim KT. BDNF-induced local translation of GluA1 is regulated by HNRNP A2/B1. SCIENCE ADVANCES 2020; 6:6/47/eabd2163. [PMID: 33219033 PMCID: PMC7679154 DOI: 10.1126/sciadv.abd2163] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Accepted: 10/08/2020] [Indexed: 05/05/2023]
Abstract
The AMPA receptor subunit GluA1 is essential for induction of synaptic plasticity. While various regulatory mechanisms of AMPA receptor expression have been identified, the underlying mechanisms of GluA1 protein synthesis are not fully understood. In neurons, axonal and dendritic mRNAs have been reported to be translated in a cap-independent manner. However, molecular mechanisms of cap-independent translation of synaptic mRNAs remain largely unknown. Here, we show that GluA1 mRNA contains an internal ribosome entry site (IRES) in the 5'UTR. We also demonstrate that heterogeneous nuclear ribonucleoprotein (hnRNP) A2/B1 interacts with GluA1 mRNA and mediates internal initiation of GluA1 Brain-derived neurotrophic factor (BDNF) stimulation increases IRES-mediated GluA1 translation via up-regulation of HNRNP A2/B1. Moreover, BDNF-induced GluA1 expression and dendritic spine density were significantly decreased in neurons lacking hnRNP A2/B1. Together, our data demonstrate that IRES-mediated translation of GluA1 mRNA is a previously unidentified feature of local expression of the AMPA receptor.
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Affiliation(s)
- Youngseob Jung
- Division of Integrative Biosciences and Biotechnology, Pohang University of Science and Technology, Pohang, Gyeongbuk 37673, Republic of Korea
| | - Ji-Young Seo
- Division of Integrative Biosciences and Biotechnology, Pohang University of Science and Technology, Pohang, Gyeongbuk 37673, Republic of Korea
| | - Hye Guk Ryu
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, Gyeongbuk 37673, Republic of Korea
| | - Do-Yeon Kim
- Department of Pharmacology, School of Dentistry, Brain Science and Engineering Institute, Kyungpook National University, Daegu 41940, Republic of Korea
| | - Kyung-Ha Lee
- Division of Cosmetic Science and Technology, Daegu Haany University, Gyeongbuk 38610, Republic of Korea
| | - Kyong-Tai Kim
- Division of Integrative Biosciences and Biotechnology, Pohang University of Science and Technology, Pohang, Gyeongbuk 37673, Republic of Korea.
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19
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Monday HR, Bourdenx M, Jordan BA, Castillo PE. CB 1-receptor-mediated inhibitory LTD triggers presynaptic remodeling via protein synthesis and ubiquitination. eLife 2020; 9:54812. [PMID: 32902378 PMCID: PMC7521925 DOI: 10.7554/elife.54812] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Accepted: 09/08/2020] [Indexed: 01/03/2023] Open
Abstract
Long-lasting forms of postsynaptic plasticity commonly involve protein synthesis-dependent structural changes of dendritic spines. However, the relationship between protein synthesis and presynaptic structural plasticity remains unclear. Here, we investigated structural changes in cannabinoid-receptor 1 (CB1)-mediated long-term depression of inhibitory transmission (iLTD), a form of presynaptic plasticity that involves a protein-synthesis-dependent long-lasting reduction in GABA release. We found that CB1-iLTD in acute rat hippocampal slices was associated with protein synthesis-dependent presynaptic structural changes. Using proteomics, we determined that CB1 activation in hippocampal neurons resulted in increased ribosomal proteins and initiation factors, but decreased levels of proteins involved in regulation of the actin cytoskeleton, such as ARPC2 and WASF1/WAVE1, and presynaptic release. Moreover, while CB1-iLTD increased ubiquitin/proteasome activity, ubiquitination but not proteasomal degradation was critical for structural and functional presynaptic CB1-iLTD. Thus, CB1-iLTD relies on both protein synthesis and ubiquitination to elicit structural changes that underlie long-term reduction of GABA release.
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Affiliation(s)
- Hannah R Monday
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, United States
| | - Mathieu Bourdenx
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, United States.,Institute for Aging Studies, Albert Einstein College of Medicine, Bronx, United States
| | - Bryen A Jordan
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, United States.,Department of Psychiatry and Behavioral Sciences, Albert Einstein College of Medicine, Bronx, United States
| | - Pablo E Castillo
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, United States.,Department of Psychiatry and Behavioral Sciences, Albert Einstein College of Medicine, Bronx, United States
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20
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Qu WR, Sun QH, Liu QQ, Jin HJ, Cui RJ, Yang W, Song DB, Li BJ. Role of CPEB3 protein in learning and memory: new insights from synaptic plasticity. Aging (Albany NY) 2020; 12:15169-15182. [PMID: 32619199 PMCID: PMC7425470 DOI: 10.18632/aging.103404] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Accepted: 05/25/2020] [Indexed: 12/28/2022]
Abstract
The cytoplasmic polyadenylation element-binding (CPEB) protein family have demonstrated a crucial role for establishing synaptic plasticity and memory in model organisms. In this review, we outline evidence for CPEB3 as a crucial regulator of learning and memory, citing evidence from behavioral, electrophysiological and morphological studies. Subsequently, the regulatory role of CPEB3 is addressed in the context of the plasticity-related proteins, including AMPA and NMDA receptor subunits, actin, and the synaptic scaffolding protein PSD95. Finally, we delve into some of the more well-studied molecular mechanisms that guide the functionality of this dynamic regulator both during synaptic stimulation and in its basal state, including a variety of upstream regulators, post-translational modifications, and important structural domains that confer the unique properties of CPEB3. Collectively, this review offers a comprehensive view of the regulatory layers that allow a pathway for CPEB3’s maintenance of translational control that guides the necessary protein changes required for the establishment and maintenance of lasting synaptic plasticity and ultimately, long term learning and memory.
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Affiliation(s)
- Wen Rui Qu
- Department of Hand Surgery, The Second Hospital of Jilin University, Changchun, Jilin Province, China.,Jilin Provincial Key Laboratory on Molecular and Chemical Genetic, The Second Hospital of Jilin University, Changchun, China
| | - Qi Han Sun
- School of Pharmacy, Jilin University, Changchun, China
| | - Qian Qian Liu
- Department of Hand Surgery, The Second Hospital of Jilin University, Changchun, Jilin Province, China.,Jilin Provincial Key Laboratory on Molecular and Chemical Genetic, The Second Hospital of Jilin University, Changchun, China
| | - Hong Juan Jin
- Department of Plastic and Reconstructive Surgery, The First Hospital of Jilin University, Changchun, China
| | - Ran Ji Cui
- Jilin Provincial Key Laboratory on Molecular and Chemical Genetic, The Second Hospital of Jilin University, Changchun, China
| | - Wei Yang
- Jilin Provincial Key Laboratory on Molecular and Chemical Genetic, The Second Hospital of Jilin University, Changchun, China
| | - De Biao Song
- Jilin Provincial Key Laboratory on Molecular and Chemical Genetic, The Second Hospital of Jilin University, Changchun, China
| | - Bing Jin Li
- Jilin Provincial Key Laboratory on Molecular and Chemical Genetic, The Second Hospital of Jilin University, Changchun, China
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21
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Barker JS, Hines RM. Regulation of GABA A Receptor Subunit Expression in Substance Use Disorders. Int J Mol Sci 2020; 21:ijms21124445. [PMID: 32580510 PMCID: PMC7352578 DOI: 10.3390/ijms21124445] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 06/17/2020] [Accepted: 06/19/2020] [Indexed: 01/02/2023] Open
Abstract
The modulation of neuronal cell firing is mediated by the release of the neurotransmitter GABA (γ-aminobuytric acid), which binds to two major families of receptors. The ionotropic GABAA receptors (GABAARs) are composed of five distinct subunits that vary in expression by brain region and cell type. The action of GABA on GABAARs is modulated by a variety of clinically and pharmacologically important drugs such as benzodiazepines and alcohol. Exposure to and abuse of these substances disrupts homeostasis and induces plasticity in GABAergic neurotransmission, often via the regulation of receptor expression. Here, we review the regulation of GABAAR subunit expression in adaptive and pathological plasticity, with a focus on substance use. We examine the factors influencing the expression of GABAAR subunit genes including the regulation of the 5′ and 3′ untranslated regions, variations in DNA methylation, immediate early genes and transcription factors that regulate subunit expression, translational and post-translational modifications, and other forms of receptor regulation beyond expression. Advancing our understanding of the factors regulating GABAAR subunit expression during adaptive plasticity, as well as during substance use and withdrawal will provide insight into the role of GABAergic signaling in substance use disorders, and contribute to the development of novel targeted therapies.
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22
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Birsa N, Bentham MP, Fratta P. Cytoplasmic functions of TDP-43 and FUS and their role in ALS. Semin Cell Dev Biol 2019; 99:193-201. [PMID: 31132467 DOI: 10.1016/j.semcdb.2019.05.023] [Citation(s) in RCA: 66] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Revised: 05/06/2019] [Accepted: 05/23/2019] [Indexed: 02/08/2023]
Abstract
TAR DNA-binding protein of 43 kDa (TDP-43) and fused in sarcoma (FUS) are RNA binding proteins (RBPs) primarily located in the nucleus, and involved in numerous aspects of RNA metabolism. Both proteins can be found to be depleted from the nucleus and accumulated in cytoplasmic inclusions in two major neurodegenerative conditions, amyotrophic lateral sclerosis and frontotemporal dementia. Recent evidences suggest that, in addition to their nuclear functions, both TDP-43 and FUS are involved in multiple processes in the cytoplasm, including mRNA stability and transport, translation, the stress response, mitochondrial function and autophagy regulation. Here, we review the most recent advances in understanding their functions in the cytoplasm and how these are affected in disease.
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Affiliation(s)
- Nicol Birsa
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, Queen Square, London, WC1N 3BG, UK.
| | - Matthew Peter Bentham
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, Queen Square, London, WC1N 3BG, UK
| | - Pietro Fratta
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, Queen Square, London, WC1N 3BG, UK; MRC Centre for Neuromuscular Disease, Queen Square, London, WC1N 3BG, UK.
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23
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Ravanidis S, Kattan FG, Doxakis E. Unraveling the Pathways to Neuronal Homeostasis and Disease: Mechanistic Insights into the Role of RNA-Binding Proteins and Associated Factors. Int J Mol Sci 2018; 19:ijms19082280. [PMID: 30081499 PMCID: PMC6121432 DOI: 10.3390/ijms19082280] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2018] [Revised: 07/26/2018] [Accepted: 07/31/2018] [Indexed: 12/13/2022] Open
Abstract
The timing, dosage and location of gene expression are fundamental determinants of brain architectural complexity. In neurons, this is, primarily, achieved by specific sets of trans-acting RNA-binding proteins (RBPs) and their associated factors that bind to specific cis elements throughout the RNA sequence to regulate splicing, polyadenylation, stability, transport and localized translation at both axons and dendrites. Not surprisingly, misregulation of RBP expression or disruption of its function due to mutations or sequestration into nuclear or cytoplasmic inclusions have been linked to the pathogenesis of several neuropsychiatric and neurodegenerative disorders such as fragile-X syndrome, autism spectrum disorders, spinal muscular atrophy, amyotrophic lateral sclerosis and frontotemporal dementia. This review discusses the roles of Pumilio, Staufen, IGF2BP, FMRP, Sam68, CPEB, NOVA, ELAVL, SMN, TDP43, FUS, TAF15, and TIA1/TIAR in RNA metabolism by analyzing their specific molecular and cellular function, the neurological symptoms associated with their perturbation, and their axodendritic transport/localization along with their target mRNAs as part of larger macromolecular complexes termed ribonucleoprotein (RNP) granules.
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Affiliation(s)
- Stylianos Ravanidis
- Basic Sciences Division I, Biomedical Research Foundation, Academy of Athens, 11527 Athens, Greece.
| | - Fedon-Giasin Kattan
- Basic Sciences Division I, Biomedical Research Foundation, Academy of Athens, 11527 Athens, Greece.
| | - Epaminondas Doxakis
- Basic Sciences Division I, Biomedical Research Foundation, Academy of Athens, 11527 Athens, Greece.
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24
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Ruan QT, Yazdani N, Beierle JA, Hixson KM, Hokenson KE, Apicco DJ, Luttik KP, Zheng K, Maziuk BF, Ash PEA, Szumlinski KK, Russek SJ, Wolozin B, Bryant CD. Changes in neuronal immunofluorescence in the C- versus N-terminal domains of hnRNP H following D1 dopamine receptor activation. Neurosci Lett 2018; 684:109-114. [PMID: 30003938 DOI: 10.1016/j.neulet.2018.07.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Revised: 07/04/2018] [Accepted: 07/08/2018] [Indexed: 12/23/2022]
Abstract
RNA binding proteins are a diverse class of proteins that regulate all aspects of RNA metabolism. Accumulating studies indicate that heterogeneous nuclear ribonucleoproteins are associated with cellular adaptations in response to drugs of abuse. We recently mapped and validated heterogeneous nuclear ribonucleoprotein H1 (Hnrnph1) as a quantitative trait gene underlying differential behavioral sensitivity to methamphetamine. The molecular mechanisms by which hnRNP H1 alters methamphetamine behaviors are unknown but could involve pre- and/or post-synaptic changes in protein localization and function. Methamphetamine initiates post-synaptic D1 dopamine receptor signaling indirectly by binding to pre-synaptic dopamine transporters and vesicular monoamine transporters of midbrain dopaminergic neurons which triggers reverse transport and accumulation of dopamine at the synapse. Here, we examined changes in neuronal localization of hnRNP H in primary rat cortical neurons that express dopamine receptors that can be modulated by the D1 or D2 dopamine receptor agonists SKF38393 and (-)-Quinpirole HCl, respectively. Basal immunostaining of hnRNP H was localized primarily to the nucleus. D1 dopamine receptor activation induced an increase in hnRNP H nuclear immunostaining as detected by immunocytochemistry with a C-domain directed antibody containing epitope near the glycine-rich domain but not with an N-domain specific antibody. Although there was no change in hnRNP H protein in the nucleus or cytoplasm, there was a decrease in Hnrnph1 transcript following D1 receptor stimulation. Taken together, these results suggest that D1 receptor activation increases availability of the hnRNP H C-terminal epitope, which could potentially reflect changes in protein-protein interactions. Thus, D1 receptor signaling could represent a key molecular post-synaptic event linking Hnrnph1 polymorphisms to drug-induced behavior.
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Affiliation(s)
- Qiu T Ruan
- Laboratory of Addiction Genetics, Department of Pharmacology and Experimental Therapeutics and Psychiatry, Boston University School of Medicine, United States; Biomolecular Pharmacology Training Program, Department of Pharmacology and Experimental Therapeutics, Boston University School of Medicine, United States; Transformative Training Program in Addiction Science, Boston University, United States
| | - Neema Yazdani
- Laboratory of Addiction Genetics, Department of Pharmacology and Experimental Therapeutics and Psychiatry, Boston University School of Medicine, United States; Biomolecular Pharmacology Training Program, Department of Pharmacology and Experimental Therapeutics, Boston University School of Medicine, United States; Transformative Training Program in Addiction Science, Boston University, United States
| | - Jacob A Beierle
- Laboratory of Addiction Genetics, Department of Pharmacology and Experimental Therapeutics and Psychiatry, Boston University School of Medicine, United States; Biomolecular Pharmacology Training Program, Department of Pharmacology and Experimental Therapeutics, Boston University School of Medicine, United States; Transformative Training Program in Addiction Science, Boston University, United States
| | - Kathryn M Hixson
- Biomolecular Pharmacology Training Program, Department of Pharmacology and Experimental Therapeutics, Boston University School of Medicine, United States; Laboratory of Translational Epilepsy, Department of Pharmacology and Experimental Therapeutics and Biology, Boston University School of Medicine, United States
| | - Kristen E Hokenson
- Biomolecular Pharmacology Training Program, Department of Pharmacology and Experimental Therapeutics, Boston University School of Medicine, United States; Laboratory of Translational Epilepsy, Department of Pharmacology and Experimental Therapeutics and Biology, Boston University School of Medicine, United States
| | - Daniel J Apicco
- Laboratory of Addiction Genetics, Department of Pharmacology and Experimental Therapeutics and Psychiatry, Boston University School of Medicine, United States; Laboratory of Neurodegeneration, Department of Pharmacology and Experimental Therapeutics and Neurology, Boston University School of Medicine, United States
| | - Kimberly P Luttik
- Laboratory of Addiction Genetics, Department of Pharmacology and Experimental Therapeutics and Psychiatry, Boston University School of Medicine, United States
| | - Karen Zheng
- Laboratory of Addiction Genetics, Department of Pharmacology and Experimental Therapeutics and Psychiatry, Boston University School of Medicine, United States
| | - Brandon F Maziuk
- Laboratory of Neurodegeneration, Department of Pharmacology and Experimental Therapeutics and Neurology, Boston University School of Medicine, United States
| | - Peter E A Ash
- Laboratory of Neurodegeneration, Department of Pharmacology and Experimental Therapeutics and Neurology, Boston University School of Medicine, United States
| | - Karen K Szumlinski
- Department of Psychological and Brain Sciences, University of California, Santa Barbara, United States
| | - Shelley J Russek
- Laboratory of Translational Epilepsy, Department of Pharmacology and Experimental Therapeutics and Biology, Boston University School of Medicine, United States
| | - Benjamin Wolozin
- Laboratory of Neurodegeneration, Department of Pharmacology and Experimental Therapeutics and Neurology, Boston University School of Medicine, United States
| | - Camron D Bryant
- Laboratory of Addiction Genetics, Department of Pharmacology and Experimental Therapeutics and Psychiatry, Boston University School of Medicine, United States.
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25
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Synaptic Paths to Neurodegeneration: The Emerging Role of TDP-43 and FUS in Synaptic Functions. Neural Plast 2018; 2018:8413496. [PMID: 29755516 PMCID: PMC5925147 DOI: 10.1155/2018/8413496] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 02/08/2018] [Accepted: 02/27/2018] [Indexed: 12/13/2022] Open
Abstract
TAR DNA-binding protein-43 KDa (TDP-43) and fused in sarcoma (FUS) as the defining pathological hallmarks for amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), coupled with ALS-FTD-causing mutations in both genes, indicate that their dysfunctions damage the motor system and cognition. On the molecular level, TDP-43 and FUS participate in the biogenesis and metabolism of coding and noncoding RNAs as well as in the transport and translation of mRNAs as part of cytoplasmic mRNA-ribonucleoprotein (mRNP) granules. Intriguingly, many of the RNA targets of TDP-43 and FUS are involved in synaptic transmission and plasticity, indicating that synaptic dysfunction could be an early event contributing to motor and cognitive deficits in ALS and FTD. Furthermore, the ability of the low-complexity prion-like domains of TDP-43 and FUS to form liquid droplets suggests a potential mechanism for mRNP assembly and conversion. This review will discuss the role of TDP-43 and FUS in RNA metabolism, with an emphasis on the involvement of this process in synaptic function and neuroprotection. This will be followed by a discussion of the potential phase separation mechanism for forming RNP granules and pathological inclusions.
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26
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Lorenz-Guertin JM, Jacob TC. GABA type a receptor trafficking and the architecture of synaptic inhibition. Dev Neurobiol 2018; 78:238-270. [PMID: 28901728 PMCID: PMC6589839 DOI: 10.1002/dneu.22536] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Revised: 09/08/2017] [Accepted: 09/08/2017] [Indexed: 12/21/2022]
Abstract
Ubiquitous expression of GABA type A receptors (GABAA R) in the central nervous system establishes their central role in coordinating most aspects of neural function and development. Dysregulation of GABAergic neurotransmission manifests in a number of human health disorders and conditions that in certain cases can be alleviated by drugs targeting these receptors. Precise changes in the quantity or activity of GABAA Rs localized at the cell surface and at GABAergic postsynaptic sites directly impact the strength of inhibition. The molecular mechanisms constituting receptor trafficking to and from these compartments therefore dictate the efficacy of GABAA R function. Here we review the current understanding of how GABAA Rs traffic through biogenesis, plasma membrane transport, and degradation. Emphasis is placed on discussing novel GABAergic synaptic proteins, receptor and scaffolding post-translational modifications, activity-dependent changes in GABAA R confinement, and neuropeptide and neurosteroid mediated changes. We further highlight modern techniques currently advancing the knowledge of GABAA R trafficking and clinically relevant neurodevelopmental diseases connected to GABAergic dysfunction. © 2017 Wiley Periodicals, Inc. Develop Neurobiol 78: 238-270, 2018.
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Affiliation(s)
- Joshua M Lorenz-Guertin
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, 15261
| | - Tija C Jacob
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, 15261
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27
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Johnston WL, Krizus A, Ramani AK, Dunham W, Youn JY, Fraser AG, Gingras AC, Dennis JW. C. elegans SUP-46, an HNRNPM family RNA-binding protein that prevents paternally-mediated epigenetic sterility. BMC Biol 2017; 15:61. [PMID: 28716093 PMCID: PMC5513350 DOI: 10.1186/s12915-017-0398-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 06/21/2017] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND In addition to DNA, gametes contribute epigenetic information in the form of histones and non-coding RNA. Epigenetic programs often respond to stressful environmental conditions and provide a heritable history of ancestral stress that allows for adaptation and propagation of the species. In the nematode C. elegans, defective epigenetic transmission often manifests as progressive germline mortality. We previously isolated sup-46 in a screen for suppressors of the hexosamine pathway gene mutant, gna-2(qa705). In this study, we examine the role of SUP-46 in stress resistance and progressive germline mortality. RESULTS We identified SUP-46 as an HNRNPM family RNA-binding protein, and uncovered a highly novel role for SUP-46 in preventing paternally-mediated progressive germline mortality following mating. Proximity biotinylation profiling of human homologs (HNRNPM, MYEF2) identified proteins of ribonucleoprotein complexes previously shown to contain non-coding RNA. Like HNRNPM and MYEF2, SUP-46 was associated with multiple RNA granules, including stress granules, and also formed granules on active chromatin. SUP-46 depletion disrupted germ RNA granules and caused ectopic sperm, increased sperm transcripts, and chronic heat stress sensitivity. SUP-46 was also required for resistance to acute heat stress, and a conserved "MYEF2" motif was identified that was needed for stress resistance. CONCLUSIONS In mammals, non-coding RNA from the sperm of stressed males has been shown to recapitulate paternal stress phenotypes in the offspring. Our results suggest that HNRNPM family proteins enable stress resistance and paternally-mediated epigenetic transmission that may be conserved across species.
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Affiliation(s)
- Wendy L. Johnston
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, ON Canada
| | - Aldis Krizus
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, ON Canada
| | - Arun K. Ramani
- Centre for Computational Medicine, The Hospital for Sick Children, Toronto, ON Canada
| | - Wade Dunham
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, ON Canada
| | - Ji Young Youn
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, ON Canada
| | - Andrew G. Fraser
- Department of Molecular Genetics, University of Toronto, Toronto, ON Canada
- The Donnelly Centre, University of Toronto, Toronto, ON Canada
| | - Anne-Claude Gingras
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, ON Canada
- Department of Molecular Genetics, University of Toronto, Toronto, ON Canada
| | - James W. Dennis
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, ON Canada
- Department of Molecular Genetics, University of Toronto, Toronto, ON Canada
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28
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Ederle H, Dormann D. TDP-43 and FUS en route from the nucleus to the cytoplasm. FEBS Lett 2017; 591:1489-1507. [PMID: 28380257 DOI: 10.1002/1873-3468.12646] [Citation(s) in RCA: 110] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Revised: 03/24/2017] [Accepted: 04/02/2017] [Indexed: 12/13/2022]
Abstract
Misfolded or mislocalized RNA-binding proteins (RBPs) and, consequently, altered mRNA processing, can cause neuronal dysfunction, eventually leading to neurodegeneration. Two prominent examples are the RBPs TAR DNA-binding protein of 43 kDa (TDP-43) and fused in sarcoma (FUS), which form pathological messenger ribonucleoprotein aggregates in patients suffering from amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), two devastating neurodegenerative disorders. Here, we review the multiple functions of TDP-43 and FUS in mRNA processing, both in the nucleus and in the cytoplasm. We discuss how TDP-43 and FUS may exit the nucleus and how defects in both nuclear and cytosolic mRNA processing events, and possibly nuclear export defects, may contribute to neurodegeneration and ALS/FTD pathogenesis.
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Affiliation(s)
- Helena Ederle
- BioMedical Center (BMC), Ludwig-Maximilians-University Munich, Planegg-Martinsried, Germany.,Graduate School of Systemic Neurosciences (GSN), Planegg-Martinsried, Germany
| | - Dorothee Dormann
- BioMedical Center (BMC), Ludwig-Maximilians-University Munich, Planegg-Martinsried, Germany.,Graduate School of Systemic Neurosciences (GSN), Planegg-Martinsried, Germany.,Munich Cluster for Systems Neurology (SyNergy), Germany
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29
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Shao G, Wang Y, Guan S, Burlingame AL, Lu F, Knox R, Ferriero DM, Jiang X. Proteomic Analysis of Mouse Cortex Postsynaptic Density following Neonatal Brain Hypoxia-Ischemia. Dev Neurosci 2017; 39:66-81. [PMID: 28315865 PMCID: PMC5519436 DOI: 10.1159/000456030] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Accepted: 01/11/2017] [Indexed: 02/02/2023] Open
Abstract
Proteomics of the synapses and postsynaptic densities (PSDs) have provided a deep understanding of protein composition and signal networks in the adult brain, which underlie neuronal plasticity and neurodegenerative or psychiatric disorders. However, there is a paucity of knowledge about the architecture and organization of PSDs in the immature brain, and how it is modified by brain injury in an early developing stage. Mass spectrometry (MS)-based proteomic analysis was performed on PSDs prepared from cortices of postnatal day 9 naïve mice or pups which had suffered hypoxic-ischemic (HI) brain injury. 512 proteins of different functional groups were identified from PSDs collected 1 h after HI injury, among which 60 have not been reported previously. Seven newly identified proteins involved in neural development were highlighted. HI injury increased the yield of PSDs at early time points upon reperfusion, and multiple proteins were recruited into PSDs following the insult. Quantitative analysis was performed using spectral counting, and proteins whose relative expression was more than 50% up- or downregulated compared to the sham animals 1 h after HI insult were reported. Validation with Western blotting demonstrated changes in expression and phosphorylation of the N-methyl-D-aspartate receptor, activation of a series of postsynaptic protein kinases and dysregulation of scaffold and adaptor proteins in response to neonatal HI insult. This work, along with other recent studies of synaptic protein profiling in the immature brain, builds a foundation for future investigation on the molecular mechanisms underlying developing plasticity. Furthermore, it provides insights into the biochemical changes of PSDs following early brain hypoxia-ischemia, which is helpful for understanding not only the injury mechanisms, but also the process of repair or replenishment of neuronal circuits during recovery from brain damage.
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Affiliation(s)
- Guo Shao
- Inner Mongolia Key Laboratory of Hypoxic Translational Medicine, Baotou Medical College, Baotou, China
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30
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Chen J, Zhan L, Lu X, Xiao C, Sun N. The Alteration of ZiBuPiYin Recipe on Proteomic Profiling of Forebrain Postsynaptic Density of db/db Mice with Diabetes-Associated Cognitive Decline. J Alzheimers Dis 2017; 56:471-489. [PMID: 27886008 DOI: 10.3233/jad-160691] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Jing Chen
- Institute (College) of Integrative Medicine, Dalian Medical University, Dalian, Liaoning, China
| | - Libin Zhan
- Nanjing University of Chinese Medicine, Nanjing, Jiangsu, China
- The Second Affiliated Hospital of Dalian Medical University, Dalian, Liaoning, China
| | - Xiaoguang Lu
- Department of Emergency Medicine, Zhongshan Hospital, Dalian University, Dalian, Liaoning, China
| | - Chi Xiao
- The Second Affiliated Hospital of Dalian Medical University, Dalian, Liaoning, China
| | - Nijing Sun
- The Second Affiliated Hospital of Dalian Medical University, Dalian, Liaoning, China
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31
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Bryant CD, Yazdani N. RNA-binding proteins, neural development and the addictions. GENES BRAIN AND BEHAVIOR 2016; 15:169-86. [PMID: 26643147 DOI: 10.1111/gbb.12273] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Revised: 10/30/2015] [Accepted: 11/09/2015] [Indexed: 12/25/2022]
Abstract
Transcriptional and post-transcriptional regulation of gene expression defines the neurobiological mechanisms that bridge genetic and environmental risk factors with neurobehavioral dysfunction underlying the addictions. More than 1000 genes in the eukaryotic genome code for multifunctional RNA-binding proteins (RBPs) that can regulate all levels of RNA biogenesis. More than 50% of these RBPs are expressed in the brain where they regulate alternative splicing, transport, localization, stability and translation of RNAs during development and adulthood. Dysfunction of RBPs can exert global effects on their targetomes that underlie neurodegenerative disorders such as Alzheimer's and Parkinson's diseases as well as neurodevelopmental disorders, including autism and schizophrenia. Here, we consider the evidence that RBPs influence key molecular targets, neurodevelopment, synaptic plasticity and neurobehavioral dysfunction underlying the addictions. Increasingly well-powered genome-wide association studies in humans and mammalian model organisms combined with ever more precise transcriptomic and proteomic approaches will continue to uncover novel and possibly selective roles for RBPs in the addictions. Key challenges include identifying the biological functions of the dynamic RBP targetomes from specific cell types throughout subcellular space (e.g. the nuclear spliceome vs. the synaptic translatome) and time and manipulating RBP programs through post-transcriptional modifications to prevent or reverse aberrant neurodevelopment and plasticity underlying the addictions.
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Affiliation(s)
- C D Bryant
- Laboratory of Addiction Genetics, Department of Pharmacology and Experimental Therapeutics and Psychiatry, Boston University School of Medicine, Boston, MA, USA
| | - N Yazdani
- Laboratory of Addiction Genetics, Department of Pharmacology and Experimental Therapeutics and Psychiatry, Boston University School of Medicine, Boston, MA, USA
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32
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Hakim V, Cohen LD, Zuchman R, Ziv T, Ziv NE. The effects of proteasomal inhibition on synaptic proteostasis. EMBO J 2016; 35:2238-2262. [PMID: 27613546 PMCID: PMC5069550 DOI: 10.15252/embj.201593594] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Accepted: 08/08/2016] [Indexed: 01/03/2023] Open
Abstract
Synaptic function crucially depends on uninterrupted synthesis and degradation of synaptic proteins. While much has been learned on synaptic protein synthesis, little is known on the routes by which synaptic proteins are degraded. Here we systematically studied how inhibition of the ubiquitin-proteasome system (UPS) affects the degradation rates of thousands of neuronal and synaptic proteins. We identified a group of proteins, including several proteins related to glutamate receptor trafficking, whose degradation rates were significantly slowed by UPS inhibition. Unexpectedly, however, degradation rates of most synaptic proteins were not significantly affected. Interestingly, many of the differential effects of UPS inhibition were readily explained by a quantitative framework that considered known metabolic turnover rates for the same proteins. In contrast to the limited effects on protein degradation, UPS inhibition profoundly and preferentially suppressed the synthesis of a large number of synaptic proteins. Our findings point to the importance of the UPS in the degradation of certain synaptic proteins, yet indicate that under basal conditions most synaptic proteins might be degraded through alternative pathways.
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Affiliation(s)
- Vicky Hakim
- The Rappaport Faculty of Medicine and Research Institute, Haifa, Israel.,Network Biology Research Laboratories, Technion - Israel Institute of Technology, Haifa, Israel
| | - Laurie D Cohen
- The Rappaport Faculty of Medicine and Research Institute, Haifa, Israel.,Network Biology Research Laboratories, Technion - Israel Institute of Technology, Haifa, Israel
| | - Rina Zuchman
- Smoler Proteomics Center, Faculty of Biology, Technion, Haifa, Israel
| | - Tamar Ziv
- Smoler Proteomics Center, Faculty of Biology, Technion, Haifa, Israel
| | - Noam E Ziv
- The Rappaport Faculty of Medicine and Research Institute, Haifa, Israel .,Network Biology Research Laboratories, Technion - Israel Institute of Technology, Haifa, Israel
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33
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Bowden HA, Dormann D. Altered mRNP granule dynamics in FTLD pathogenesis. J Neurochem 2016; 138 Suppl 1:112-33. [PMID: 26938019 DOI: 10.1111/jnc.13601] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Revised: 02/29/2016] [Accepted: 03/01/2016] [Indexed: 12/13/2022]
Abstract
In neurons, RNA-binding proteins (RBPs) play a key role in post-transcriptional gene regulation, for example alternative splicing, mRNA localization in neurites and local translation upon synaptic stimulation. There is increasing evidence that defective or mislocalized RBPs - and consequently altered mRNA processing - lead to neuronal dysfunction and cause neurodegeneration, including frontotemporal lobar degeneration and amyotrophic lateral sclerosis. Cytosolic RBP aggregates containing TAR DNA-binding protein of 43 kDa (TDP-43) or fused in sarcoma (FUS) are a common hallmark of both disorders. There is mounting evidence that translationally silent mRNP granules, such as stress granules or transport granules, play an important role in the formation of these RBP aggregates. These granules are thought to be 'catalytic convertors' of RBP aggregation by providing a high local concentration of RBPs. As recently shown in vitro, RBPs that contain a so-called low-complexity domain start to 'solidify' and eventually aggregate at high protein concentrations. The same may happen in mRNP granules in vivo, leading to 'solidified' granules that lose their dynamic properties and ability to fulfill their physiological functions. This may result in a disturbed stress response, altered mRNA transport and local translation, and formation of pathological TDP-43 or FUS aggregates, all of which may contribute to neuronal dysfunction and neurodegeneration. Here, we discuss the general functional properties of these mRNP granules, how their dynamics may be disrupted in frontotemporal lobar degeneration/amyotrophic lateral sclerosis, for example by loss or gain of function of TDP-43 and FUS, and how this may contribute to the development of RBP aggregates and neurotoxicity. In this review, we discuss how dynamic mRNP granules, such as stress granules or neuronal transport granules, may be converted into pathological aggregates containing misfolded RNA-binding proteins (RBPs), such as TDP-43 and FUS. Abnormal interactions between low-complexity domains in RBPs may cause dynamic mRNP granules to solidify and become dysfunctional. This may result in a disturbed stress response, altered mRNA transport and local translation, as well as RBP aggregation, all of which may contribute to neuronal dysfunction and neurodegeneration.
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Affiliation(s)
- Hilary A Bowden
- Graduate School of Systemic Neurosciences (GSN), Planegg-Martinsried, Germany
| | - Dorothee Dormann
- BioMedical Center (BMC), Ludwig-Maximilians-University Munich, Planegg-Martinsried, Germany.,Graduate School of Systemic Neurosciences (GSN), Planegg-Martinsried, Germany.,Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
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34
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Proteostasis and RNA Binding Proteins in Synaptic Plasticity and in the Pathogenesis of Neuropsychiatric Disorders. Neural Plast 2016; 2016:3857934. [PMID: 26904297 PMCID: PMC4745388 DOI: 10.1155/2016/3857934] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Accepted: 09/30/2015] [Indexed: 12/30/2022] Open
Abstract
Decades of research have demonstrated that rapid alterations in protein abundance are required for synaptic plasticity, a cellular correlate for learning and memory. Control of protein abundance, known as proteostasis, is achieved across a complex neuronal morphology that includes a tortuous axon as well as an extensive dendritic arbor supporting thousands of individual synaptic compartments. To regulate the spatiotemporal synthesis of proteins, neurons must efficiently coordinate the transport and metabolism of mRNAs. Among multiple levels of regulation, transacting RNA binding proteins (RBPs) control proteostasis by binding to mRNAs and mediating their transport and translation in response to synaptic activity. In addition to synthesis, protein degradation must be carefully balanced for optimal proteostasis, as deviations resulting in excess or insufficient abundance of key synaptic factors produce pathologies. As such, mutations in components of the proteasomal or translational machinery, including RBPs, have been linked to the pathogenesis of neurological disorders such as Fragile X Syndrome (FXS), Fragile X Tremor Ataxia Syndrome (FXTAS), and Autism Spectrum Disorders (ASD). In this review, we summarize recent scientific findings, highlight ongoing questions, and link basic molecular mechanisms to the pathogenesis of common neuropsychiatric disorders.
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35
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Hnrnph1 Is A Quantitative Trait Gene for Methamphetamine Sensitivity. PLoS Genet 2015; 11:e1005713. [PMID: 26658939 PMCID: PMC4675533 DOI: 10.1371/journal.pgen.1005713] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Accepted: 11/09/2015] [Indexed: 11/19/2022] Open
Abstract
Psychostimulant addiction is a heritable substance use disorder; however its genetic basis is almost entirely unknown. Quantitative trait locus (QTL) mapping in mice offers a complementary approach to human genome-wide association studies and can facilitate environment control, statistical power, novel gene discovery, and neurobiological mechanisms. We used interval-specific congenic mouse lines carrying various segments of chromosome 11 from the DBA/2J strain on an isogenic C57BL/6J background to positionally clone a 206 kb QTL (50,185,512–50,391,845 bp) that was causally associated with a reduction in the locomotor stimulant response to methamphetamine (2 mg/kg, i.p.; DBA/2J < C57BL/6J)—a non-contingent, drug-induced behavior that is associated with stimulation of the dopaminergic reward circuitry. This chromosomal region contained only two protein coding genes—heterogeneous nuclear ribonucleoprotein, H1 (Hnrnph1) and RUN and FYVE domain-containing 1 (Rufy1). Transcriptome analysis via mRNA sequencing in the striatum implicated a neurobiological mechanism involving a reduction in mesolimbic innervation and striatal neurotransmission. For instance, Nr4a2 (nuclear receptor subfamily 4, group A, member 2), a transcription factor crucial for midbrain dopaminergic neuron development, exhibited a 2.1-fold decrease in expression (DBA/2J < C57BL/6J; p 4.2 x 10−15). Transcription activator-like effector nucleases (TALENs)-mediated introduction of frameshift deletions in the first coding exon of Hnrnph1, but not Rufy1, recapitulated the reduced methamphetamine behavioral response, thus identifying Hnrnph1 as a quantitative trait gene for methamphetamine sensitivity. These results define a novel contribution of Hnrnph1 to neurobehavioral dysfunction associated with dopaminergic neurotransmission. These findings could have implications for understanding the genetic basis of methamphetamine addiction in humans and the development of novel therapeutics for prevention and treatment of substance abuse and possibly other psychiatric disorders. Both genetic and environmental factors can powerfully modulate susceptibility to substance use disorders. Quantitative trait locus (QTL) mapping is an unbiased discovery-based approach that is used to identify novel genetic factors and provide new mechanistic insight into phenotypic variation associated with disease. In this study, we focused on the genetic basis of variation in sensitivity to the acute locomotor stimulant response to methamphetamine which is a behavioral phenotype in rodents that is associated with stimulated dopamine release and activation of the brain reward circuitry involved in addiction. Using brute force monitoring of recombination events associated with changes in behavior, we fortuitously narrowed the genotype-phenotype association down to just two genes that we subsequently targeted using a contemporary genome editing approach. The gene that we validated–Hnrnph1 –is an RNA binding protein that did not have any previously known function in psychostimulant behavior or psychostimulant addiction. Our behavioral data combined with our gene expression results provide a compelling rationale for a new line of investigation regarding Hnrnph1 and its role in neural development and plasticity associated with the addictions and perhaps other dopamine-dependent psychiatric disorders.
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36
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Mircsof D, Langouët M, Rio M, Moutton S, Siquier-Pernet K, Bole-Feysot C, Cagnard N, Nitschke P, Gaspar L, Žnidarič M, Alibeu O, Fritz AK, Wolfer DP, Schröter A, Bosshard G, Rudin M, Koester C, Crestani F, Seebeck P, Boddaert N, Prescott K, Hines R, Moss SJ, Fritschy JM, Munnich A, Amiel J, Brown SA, Tyagarajan SK, Colleaux L. Mutations in NONO lead to syndromic intellectual disability and inhibitory synaptic defects. Nat Neurosci 2015; 18:1731-6. [PMID: 26571461 PMCID: PMC5392243 DOI: 10.1038/nn.4169] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Accepted: 10/15/2015] [Indexed: 12/14/2022]
Abstract
The NONO protein has been characterized as an important transcriptional regulator in diverse cellular contexts. Here we show that loss of NONO function is a likely cause of human intellectual disability and that NONO-deficient mice have cognitive and affective deficits. Correspondingly, we find specific defects at inhibitory synapses, where NONO regulates synaptic transcription and gephyrin scaffold structure. Our data identify NONO as a possible neurodevelopmental disease gene and highlight the key role of the DBHS protein family in functional organization of GABAergic synapses.
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Affiliation(s)
- Dennis Mircsof
- Chronobiology and Sleep Research Group, Institute of Pharmacology and Toxicology, University of Zürich, Zürich, Switzerland.,Neuromorphology Group, Institute of Pharmacology and Toxicology, University of Zürich, Zürich, Switzerland
| | - Maéva Langouët
- INSERM UMR 1163, Laboratory of Molecular and Pathophysiological Bases of Cognitive Disorders, Paris Descartes-Sorbonne Paris Cité University, Imagine Institute, Necker-Enfants Malades Hospital, Paris, France
| | - Marlène Rio
- INSERM UMR 1163, Laboratory of Molecular and Pathophysiological Bases of Cognitive Disorders, Paris Descartes-Sorbonne Paris Cité University, Imagine Institute, Necker-Enfants Malades Hospital, Paris, France.,Service de Génétique, Hôpital Necker-Enfants Malades, Assistance Publique Hôpitaux de Paris, Paris, France
| | - Sébastien Moutton
- INSERM UMR 1163, Laboratory of Molecular and Pathophysiological Bases of Cognitive Disorders, Paris Descartes-Sorbonne Paris Cité University, Imagine Institute, Necker-Enfants Malades Hospital, Paris, France
| | - Karine Siquier-Pernet
- INSERM UMR 1163, Laboratory of Molecular and Pathophysiological Bases of Cognitive Disorders, Paris Descartes-Sorbonne Paris Cité University, Imagine Institute, Necker-Enfants Malades Hospital, Paris, France
| | - Christine Bole-Feysot
- Genomic Platform, INSERM UMR 1163, Paris Descartes-Sorbonne Paris Cité University, Imagine Institute, Necker-Enfants Malades Hospital, Paris, France
| | - Nicolas Cagnard
- Bioinformatic Platform, INSERM UMR 1163, Paris Descartes-Sorbonne Paris Cité University, Imagine Institute, Necker-Enfants Malades Hospital, Paris, France
| | - Patrick Nitschke
- Bioinformatic Platform, INSERM UMR 1163, Paris Descartes-Sorbonne Paris Cité University, Imagine Institute, Necker-Enfants Malades Hospital, Paris, France
| | - Ludmila Gaspar
- Chronobiology and Sleep Research Group, Institute of Pharmacology and Toxicology, University of Zürich, Zürich, Switzerland
| | - Matej Žnidarič
- Chronobiology and Sleep Research Group, Institute of Pharmacology and Toxicology, University of Zürich, Zürich, Switzerland
| | - Olivier Alibeu
- Genomic Platform, INSERM UMR 1163, Paris Descartes-Sorbonne Paris Cité University, Imagine Institute, Necker-Enfants Malades Hospital, Paris, France
| | - Ann-Kristina Fritz
- Institute of Anatomy, University of Zürich and Institute of Human Movement Sciences and Sport, ETH Zürich, Switzerland
| | - David P Wolfer
- Institute of Anatomy, University of Zürich and Institute of Human Movement Sciences and Sport, ETH Zürich, Switzerland
| | - Aileen Schröter
- Molecular Imaging and Functional Pharmacology Group, University of Zürich, Zürich, Switzerland
| | - Giovanna Bosshard
- Neuromorphology Group, Institute of Pharmacology and Toxicology, University of Zürich, Zürich, Switzerland
| | - Markus Rudin
- Molecular Imaging and Functional Pharmacology Group, University of Zürich, Zürich, Switzerland
| | - Christina Koester
- Neuromorphology Group, Institute of Pharmacology and Toxicology, University of Zürich, Zürich, Switzerland
| | - Florence Crestani
- Neuromorphology Group, Institute of Pharmacology and Toxicology, University of Zürich, Zürich, Switzerland
| | - Petra Seebeck
- Center for Integrative Rodent Physiology, University of Zürich, Zürich, Switzerland
| | - Nathalie Boddaert
- INSERM UMR 1163, Laboratory of Molecular and Pathophysiological Bases of Cognitive Disorders, Paris Descartes-Sorbonne Paris Cité University, Imagine Institute, Necker-Enfants Malades Hospital, Paris, France.,Service de radiologie pédiatrique, Hôpital Necker-Enfants Malades, Assistance Publique Hôpitaux de Paris, Paris, France
| | - Katrina Prescott
- Yorkshire Regional Genetics Service, Leeds Teaching Hospitals National Health Service Trust, Department of Clinical Genetics, Chapel Allerton Hospital, Chapeltown Road, Leeds, UK
| | | | - Rochelle Hines
- Tufts University, Sackler School of Graduate Biomedical Sciences, Boston, Massachusetts, USA
| | - Steven J Moss
- Tufts University, Sackler School of Graduate Biomedical Sciences, Boston, Massachusetts, USA
| | - Jean-Marc Fritschy
- Neuromorphology Group, Institute of Pharmacology and Toxicology, University of Zürich, Zürich, Switzerland
| | - Arnold Munnich
- INSERM UMR 1163, Laboratory of Molecular and Pathophysiological Bases of Cognitive Disorders, Paris Descartes-Sorbonne Paris Cité University, Imagine Institute, Necker-Enfants Malades Hospital, Paris, France
| | - Jeanne Amiel
- INSERM UMR 1163, Laboratory of Molecular and Pathophysiological Bases of Cognitive Disorders, Paris Descartes-Sorbonne Paris Cité University, Imagine Institute, Necker-Enfants Malades Hospital, Paris, France.,Service de Génétique, Hôpital Necker-Enfants Malades, Assistance Publique Hôpitaux de Paris, Paris, France
| | - Steven A Brown
- Chronobiology and Sleep Research Group, Institute of Pharmacology and Toxicology, University of Zürich, Zürich, Switzerland
| | - Shiva K Tyagarajan
- Neuromorphology Group, Institute of Pharmacology and Toxicology, University of Zürich, Zürich, Switzerland
| | - Laurence Colleaux
- INSERM UMR 1163, Laboratory of Molecular and Pathophysiological Bases of Cognitive Disorders, Paris Descartes-Sorbonne Paris Cité University, Imagine Institute, Necker-Enfants Malades Hospital, Paris, France
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GluN2B-Containing NMDA Receptors Regulate AMPA Receptor Traffic through Anchoring of the Synaptic Proteasome. J Neurosci 2015; 35:8462-79. [PMID: 26041915 DOI: 10.1523/jneurosci.3567-14.2015] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
NMDA receptors play a central role in shaping the strength of synaptic connections throughout development and in mediating synaptic plasticity mechanisms that underlie some forms of learning and memory formation in the CNS. In the hippocampus and the neocortex, GluN1 is combined primarily with GluN2A and GluN2B, which are differentially expressed during development and confer distinct molecular and physiological properties to NMDA receptors. The contribution of each subunit to the synaptic traffic of NMDA receptors and therefore to their role during development and in synaptic plasticity is still controversial. We report a critical role for the GluN2B subunit in regulating NMDA receptor synaptic targeting. In the absence of GluN2B, the synaptic levels of AMPA receptors are increased and accompanied by decreased constitutive endocytosis of GluA1-AMPA receptor. We used quantitative proteomic analysis to identify changes in the composition of postsynaptic densities from GluN2B(-/-) mouse primary neuronal cultures and found altered levels of several ubiquitin proteasome system components, in particular decreased levels of proteasome subunits. Enhancing the proteasome activity with a novel proteasome activator restored the synaptic levels of AMPA receptors in GluN2B(-/-) neurons and their endocytosis, revealing that GluN2B-mediated anchoring of the synaptic proteasome is responsible for fine tuning AMPA receptor synaptic levels under basal conditions.
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38
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Reichenbach N, Herrmann U, Kähne T, Schicknick H, Pielot R, Naumann M, Dieterich DC, Gundelfinger ED, Smalla KH, Tischmeyer W. Differential effects of dopamine signalling on long-term memory formation and consolidation in rodent brain. Proteome Sci 2015; 13:13. [PMID: 25852303 PMCID: PMC4387680 DOI: 10.1186/s12953-015-0069-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Accepted: 02/25/2015] [Indexed: 12/01/2022] Open
Abstract
Background Using auditory discrimination learning in gerbils, we have previously shown that activation of auditory-cortical D1/D5 dopamine receptors facilitates mTOR-mediated, protein synthesis-dependent mechanisms of memory consolidation and anterograde memory formation. To understand molecular mechanisms of this facilitatory effect, we tested the impact of local pharmacological activation of different D1/D5 dopamine receptor signalling modes in the auditory cortex. To this end, protein patterns in soluble and synaptic protein-enriched fractions from cortical, hippocampal and striatal brain regions of ligand- and vehicle-treated gerbils were analysed by 2D gel electrophoresis and mass spectrometry 24 h after intervention. Results After auditory-cortical injection of SKF38393 – a D1/D5 dopamine receptor-selective agonist reported to activate the downstream effectors adenylyl cyclase and phospholipase C – prominent proteomic alterations compared to vehicle-treated controls appeared in the auditory cortex, striatum, and hippocampus, whereas only minor changes were detectable in the frontal cortex. In contrast, auditory-cortical injection of SKF83959 – a D1/D5 agonist reported to preferentially stimulate phospholipase C – induced pronounced changes in the frontal cortex. At the molecular level, we detected altered regulation of cytoskeletal and scaffolding proteins, changes in proteins with functions in energy metabolism, local protein synthesis, and synaptic signalling. Interestingly, abundance and/or subcellular localisation of the predominantly presynaptic protein α-synuclein displayed dopaminergic regulation. To assess the role of α-synuclein for dopaminergic mechanisms of memory modulation, we tested the impact of post-conditioning systemic pharmacological activation of different D1/D5 dopamine receptor signalling modes on auditory discrimination learning in α-synuclein-mutant mice. In C57BL/6JOlaHsd mice, bearing a spontaneous deletion of the α-synuclein-encoding gene, but not in the related substrains C57BL/6JCrl and C57BL/6JRccHsd, adenylyl cyclase-mediated signalling affected acquisition rates over future learning episodes, whereas phospholipase C-mediated signalling affected final memory performance. Conclusions Dopamine signalling modes via D1/D5 receptors in the auditory cortex differentially impact protein profiles related to rearrangement of cytomatrices, energy metabolism, and synaptic neurotransmission in cortical, hippocampal, and basal brain structures. Altered dopamine neurotransmission in α-synuclein-deficient mice revealed that distinct D1/D5 receptor signalling modes may control different aspects of memory consolidation. Electronic supplementary material The online version of this article (doi:10.1186/s12953-015-0069-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Nicole Reichenbach
- Special Lab Molecular Biological Techniques, Leibniz Institute for Neurobiology, Magdeburg, 39118 Germany ; Present address: Research Group Neurovascular Diseases, German Center for Neurodegenerative Diseases (DZNE), Ludwig-Erhard-Allee 2, Bonn, 53175 Germany
| | - Ulrike Herrmann
- Special Lab Molecular Biological Techniques, Leibniz Institute for Neurobiology, Magdeburg, 39118 Germany ; Present address: Division of Cellular Neurobiology, Zoological Institute, TU Braunschweig, Braunschweig, 38106 Germany
| | - Thilo Kähne
- Institute of Experimental Internal Medicine, Medical School, Otto von Guericke University, Magdeburg, 39120 Germany
| | - Horst Schicknick
- Special Lab Molecular Biological Techniques, Leibniz Institute for Neurobiology, Magdeburg, 39118 Germany
| | - Rainer Pielot
- Department Neurochemistry and Molecular Biology, Leibniz Institute for Neurobiology, Magdeburg, 39118 Germany
| | - Michael Naumann
- Institute of Experimental Internal Medicine, Medical School, Otto von Guericke University, Magdeburg, 39120 Germany
| | - Daniela C Dieterich
- Research Group Neuralomics, Leibniz Institute for Neurobiology, Magdeburg, 39118 Germany ; Institute for Pharmacology and Toxicology, Medical Faculty, Otto-von-Guericke-University Magdeburg, Magdeburg, 39120 Germany ; Center for Behavioral Brain Sciences, Magdeburg, 39106 Germany
| | - Eckart D Gundelfinger
- Department Neurochemistry and Molecular Biology, Leibniz Institute for Neurobiology, Magdeburg, 39118 Germany ; Center for Behavioral Brain Sciences, Magdeburg, 39106 Germany ; Molecular Neurobiology, Medical Faculty, Otto-von-Guericke-University Magdeburg, Magdeburg, 39120 Germany
| | - Karl-Heinz Smalla
- Special Lab Molecular Biological Techniques, Leibniz Institute for Neurobiology, Magdeburg, 39118 Germany ; Center for Behavioral Brain Sciences, Magdeburg, 39106 Germany
| | - Wolfgang Tischmeyer
- Special Lab Molecular Biological Techniques, Leibniz Institute for Neurobiology, Magdeburg, 39118 Germany ; Center for Behavioral Brain Sciences, Magdeburg, 39106 Germany
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Abstract
Heterogeneous nuclear ribonucleoprotein K (hnRNP K) is an RNA-binding protein implicated in RNA metabolism. Here, we investigated the role of hnRNP K in synapse function. We demonstrated that hnRNP K regulates dendritic spine density and long-term potentiation (LTP) in cultured hippocampal neurons from embryonic rats. LTP requires the extracellular signal-regulated kinase (ERK)1/2-mediated phosphorylation and cytoplasmic accumulation of hnRNP K. Moreover, hnRNP K knockdown prevents ERK cascade activation and GluA1-S845 phosphorylation and surface delivery, which are essential steps for LTP. These findings establish hnRNP K as a new critical regulator of synaptic transmission and plasticity in hippocampal neurons.
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40
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Zhang G, Deinhardt K, Neubert TA. Stable isotope labeling by amino acids in cultured primary neurons. Methods Mol Biol 2014; 1188:57-64. [PMID: 25059604 PMCID: PMC4212509 DOI: 10.1007/978-1-4939-1142-4_5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Cultured primary neurons are a well-established model for the study of neuronal function. Conventional stable isotope labeling with amino acids in cell culture (SILAC) requires nearly complete metabolic labeling of proteins and therefore is difficult to apply to cultured primary neurons, which do not divide in culture. Here we describe a protocol that utilizes a multiplex SILAC labeling strategy for primary cultured neurons. In this strategy, two different sets of heavy amino acids are used for labeling cells for the different experimental conditions. This allows for a straightforward SILAC quantitation using partially labeled cells because the two cell populations are always equally labeled.
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Affiliation(s)
- Guoan Zhang
- Dept. of Biochemistry and Molecular Pharmacology and Kimmel Center for Molecular Medicine at the Skirball Institute, New York University School of Medicine, New York, NY 10016, USA
| | - Katrin Deinhardt
- Institute for Life Sciences and Centre for Biological Sciences, University of Southampton, Life Sciences Building 85, Southampton, SO17 1BJ, UK
| | - Thomas A. Neubert
- Dept. of Biochemistry and Molecular Pharmacology and Kimmel Center for Molecular Medicine at the Skirball Institute, New York University School of Medicine, New York, NY 10016, USA
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41
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Abstract
The ability to induce and study neuronal plasticity in single dendritic spines has greatly advanced our understanding of the signaling mechanisms that mediate long-term potentiation. It is now clear that in addition to compartmentalization by the individual spine, subcompartmentalization of biochemical signals occurs at specialized microdomains within the spine. The spatiotemporal coordination of these complex cascades allows for the concomitant remodeling of the postsynaptic density and actin spinoskeleton and for the regulation of membrane traffic to express functional and structural plasticity. Here, we highlight recent findings in the signaling cascades at spine microdomains as well as the challenges and approaches to studying plasticity at the spine level.
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Affiliation(s)
- Lesley A Colgan
- Neuronal Signal Transduction, Max Planck Florida Institute for Neuroscience, Jupiter, Florida 33458; ,
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42
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Barbarese E, Ifrim MF, Hsieh L, Guo C, Tatavarty V, Maggipinto MJ, Korza G, Tutolo JW, Giampetruzzi A, Le H, Ma XM, Levine E, Bishop B, Kim DO, Kuwada S, Carson JH. Conditional knockout of tumor overexpressed gene in mouse neurons affects RNA granule assembly, granule translation, LTP and short term habituation. PLoS One 2013; 8:e69989. [PMID: 23936366 PMCID: PMC3735573 DOI: 10.1371/journal.pone.0069989] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Accepted: 06/14/2013] [Indexed: 12/20/2022] Open
Abstract
In neurons, specific RNAs are assembled into granules, which are translated in dendrites, however the functional consequences of granule assembly are not known. Tumor overexpressed gene (TOG) is a granule-associated protein containing multiple binding sites for heterogeneous nuclear ribonucleoprotein (hnRNP) A2, another granule component that recognizes cis-acting sequences called hnRNP A2 response elements (A2REs) present in several granule RNAs. Translation in granules is sporadic, which is believed to reflect monosomal translation, with occasional bursts, which are believed to reflect polysomal translation. In this study, TOG expression was conditionally knocked out (TOG cKO) in mouse hippocampal neurons using cre/lox technology. In TOG cKO cultured neurons granule assembly and bursty translation of activity-regulated cytoskeletal associated (ARC) mRNA, an A2RE RNA, are disrupted. In TOG cKO brain slices synaptic sensitivity and long term potentiation (LTP) are reduced. TOG cKO mice exhibit hyperactivity, perseveration and impaired short term habituation. These results suggest that in hippocampal neurons TOG is required for granule assembly, granule translation and synaptic plasticity, and affects behavior.
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Affiliation(s)
- Elisa Barbarese
- Department of Neuroscience, University of Connecticut Health Center, Farmington, Connecticut, United States of America.
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Hörnberg H, Holt C. RNA-binding proteins and translational regulation in axons and growth cones. Front Neurosci 2013; 7:81. [PMID: 23734093 PMCID: PMC3661996 DOI: 10.3389/fnins.2013.00081] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Accepted: 05/06/2013] [Indexed: 01/11/2023] Open
Abstract
RNA localization and regulation play an important role in the developing and adult nervous system. In navigating axons, extrinsic cues can elicit rapid local protein synthesis that mediates directional or morphological responses. The mRNA repertoire in axons is large and dynamically changing, yet studies suggest that only a subset of these mRNAs are translated after cue stimulation, suggesting the need for a high level of translational regulation. Here, we review the role of RNA-binding proteins (RBPs) as local regulators of translation in developing axons. We focus on their role in growth, guidance, and synapse formation, and discuss the mechanisms by which they regulate translation in axons.
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Affiliation(s)
- Hanna Hörnberg
- Department of Physiology Development and Neuroscience, University of Cambridge Cambridge, UK
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Cohen LD, Zuchman R, Sorokina O, Müller A, Dieterich DC, Armstrong JD, Ziv T, Ziv NE. Metabolic turnover of synaptic proteins: kinetics, interdependencies and implications for synaptic maintenance. PLoS One 2013; 8:e63191. [PMID: 23658807 PMCID: PMC3642143 DOI: 10.1371/journal.pone.0063191] [Citation(s) in RCA: 143] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2013] [Accepted: 03/29/2013] [Indexed: 01/11/2023] Open
Abstract
Chemical synapses contain multitudes of proteins, which in common with all proteins, have finite lifetimes and therefore need to be continuously replaced. Given the huge numbers of synaptic connections typical neurons form, the demand to maintain the protein contents of these connections might be expected to place considerable metabolic demands on each neuron. Moreover, synaptic proteostasis might differ according to distance from global protein synthesis sites, the availability of distributed protein synthesis facilities, trafficking rates and synaptic protein dynamics. To date, the turnover kinetics of synaptic proteins have not been studied or analyzed systematically, and thus metabolic demands or the aforementioned relationships remain largely unknown. In the current study we used dynamic Stable Isotope Labeling with Amino acids in Cell culture (SILAC), mass spectrometry (MS), Fluorescent Non-Canonical Amino acid Tagging (FUNCAT), quantitative immunohistochemistry and bioinformatics to systematically measure the metabolic half-lives of hundreds of synaptic proteins, examine how these depend on their pre/postsynaptic affiliation or their association with particular molecular complexes, and assess the metabolic load of synaptic proteostasis. We found that nearly all synaptic proteins identified here exhibited half-lifetimes in the range of 2-5 days. Unexpectedly, metabolic turnover rates were not significantly different for presynaptic and postsynaptic proteins, or for proteins for which mRNAs are consistently found in dendrites. Some functionally or structurally related proteins exhibited very similar turnover rates, indicating that their biogenesis and degradation might be coupled, a possibility further supported by bioinformatics-based analyses. The relatively low turnover rates measured here (∼0.7% of synaptic protein content per hour) are in good agreement with imaging-based studies of synaptic protein trafficking, yet indicate that the metabolic load synaptic protein turnover places on individual neurons is very substantial.
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Affiliation(s)
- Laurie D. Cohen
- Technion Faculty of Medicine, Lorry Lokey Center for Life Sciences and Engineering, Technion, Haifa, Israel
- Network Biology Research Laboratories, Lorry Lokey Center for Life Sciences and Engineering, Technion, Haifa, Israel
| | - Rina Zuchman
- Smoler Proteomics Center, Faculty of Biology, Technion, Haifa, Israel
| | - Oksana Sorokina
- Institute for Adaptive and Neural Computation, University of Edinburgh, Edinburgh, United Kingdom
| | - Anke Müller
- Leibniz-Institute for Neurobiology, Magdeburg, Germany
- Institute for Pharmacology and Toxicology, Otto-von-Guericke University, Magdeburg, Germany
| | - Daniela C. Dieterich
- Leibniz-Institute for Neurobiology, Magdeburg, Germany
- Institute for Pharmacology and Toxicology, Otto-von-Guericke University, Magdeburg, Germany
| | - J. Douglas Armstrong
- Institute for Adaptive and Neural Computation, University of Edinburgh, Edinburgh, United Kingdom
| | - Tamar Ziv
- Smoler Proteomics Center, Faculty of Biology, Technion, Haifa, Israel
| | - Noam E. Ziv
- Technion Faculty of Medicine, Lorry Lokey Center for Life Sciences and Engineering, Technion, Haifa, Israel
- Network Biology Research Laboratories, Lorry Lokey Center for Life Sciences and Engineering, Technion, Haifa, Israel
- * E-mail:
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45
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Leal G, Comprido D, Duarte CB. BDNF-induced local protein synthesis and synaptic plasticity. Neuropharmacology 2013; 76 Pt C:639-56. [PMID: 23602987 DOI: 10.1016/j.neuropharm.2013.04.005] [Citation(s) in RCA: 435] [Impact Index Per Article: 39.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2013] [Revised: 03/25/2013] [Accepted: 04/03/2013] [Indexed: 12/16/2022]
Abstract
Brain-derived neurotrophic factor (BDNF) is an important regulator of synaptic transmission and long-term potentiation (LTP) in the hippocampus and in other brain regions, playing a role in the formation of certain forms of memory. The effects of BDNF in LTP are mediated by TrkB (tropomyosin-related kinase B) receptors, which are known to be coupled to the activation of the Ras/ERK, phosphatidylinositol 3-kinase/Akt and phospholipase C-γ (PLC-γ) pathways. The role of BDNF in LTP is best studied in the hippocampus, where the neurotrophin acts at pre- and post-synaptic levels. Recent studies have shown that BDNF regulates the transport of mRNAs along dendrites and their translation at the synapse, by modulating the initiation and elongation phases of protein synthesis, and by acting on specific miRNAs. Furthermore, the effect of BDNF on transcription regulation may further contribute to long-term changes in the synaptic proteome. In this review we discuss the recent progress in understanding the mechanisms contributing to the short- and long-term regulation of the synaptic proteome by BDNF, and the role in synaptic plasticity, which is likely to influence learning and memory formation. This article is part of the Special Issue entitled 'BDNF Regulation of Synaptic Structure, Function, and Plasticity'.
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Affiliation(s)
- Graciano Leal
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, 3004-517 Coimbra, Portugal; Department of Life Sciences, University of Coimbra, 3004-517 Coimbra, Portugal
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RNA-binding protein Sam68 controls synapse number and local β-actin mRNA metabolism in dendrites. Proc Natl Acad Sci U S A 2013; 110:3125-30. [PMID: 23382180 DOI: 10.1073/pnas.1209811110] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Proper synaptic function requires the spatial and temporal compartmentalization of RNA metabolism via transacting RNA-binding proteins (RBPs). Loss of RBP activity leads to abnormal posttranscriptional regulation and results in diverse neurological disorders with underlying deficits in synaptic morphology and transmission. Functional loss of the 68-kDa RBP Src associated in mitosis (Sam68) is associated with the pathogenesis of the neurological disorder fragile X tremor/ataxia syndrome. Sam68 binds to the mRNA of β-actin (actb), an integral cytoskeletal component of dendritic spines. We show that Sam68 knockdown or disruption of the binding between Sam68 and its actb mRNA cargo in primary hippocampal cultures decreases the amount of actb mRNA in the synaptodendritic compartment and results in fewer dendritic spines. Consistent with these observations, we find that Sam68-KO mice have reduced levels of actb mRNA associated with synaptic polysomes and diminished levels of synaptic actb protein, suggesting that Sam68 promotes the translation of actb mRNA at synapses in vivo. Moreover, genetic knockout of Sam68 or acute knockdown in vivo results in fewer excitatory synapses in the hippocampal formation as assessed morphologically and functionally. Therefore, we propose that Sam68 regulates synapse number in a cell-autonomous manner through control of postsynaptic actb mRNA metabolism. Our research identifies a role for Sam68 in synaptodendritic posttranscriptional regulation of actb and may provide insight into the pathophysiology of fragile X tremor/ataxia syndrome.
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47
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Culturing pyramidal neurons from the early postnatal mouse hippocampus and cortex. Nat Protoc 2012; 7:1741-54. [PMID: 22936216 DOI: 10.1038/nprot.2012.099] [Citation(s) in RCA: 454] [Impact Index Per Article: 37.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The ability to culture and maintain postnatal mouse hippocampal and cortical neurons is highly advantageous, particularly for studies on genetically engineered mouse models. Here we present a protocol to isolate and culture pyramidal neurons from the early postnatal (P0-P1) mouse hippocampus and cortex. These low-density dissociated cultures are grown on poly-L-lysine-coated glass substrates without feeder layers. Cultured neurons survive well, develop extensive axonal and dendritic arbors, express neuronal and synaptic markers, and form functional synaptic connections. Further, they are highly amenable to low- and high-efficiency transfection and time-lapse imaging. This optimized cell culture technique can be used to culture and maintain neurons for a variety of applications including immunocytochemistry, biochemical studies, shRNA-mediated knockdown and live imaging studies. The preparation of the glass substrate must begin 5 d before the culture. The dissection and plating out of neurons takes 3-4 h and neurons can be maintained in culture for up to 4 weeks.
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48
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mRNA translation: regulating an out of soma experience. Curr Opin Cell Biol 2012; 24:554-7. [PMID: 22770873 DOI: 10.1016/j.ceb.2012.06.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2012] [Accepted: 06/17/2012] [Indexed: 11/21/2022]
Abstract
The regulation of protein synthesis in discrete cellular subdomains, or local protein synthesis, has important roles in development as well as brain function. This review will discuss some recent findings that shed new light on mRNA translation regulation and how these layers of regulation may work together to elicit tissue specific and spatially restricted gene expression.
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