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Cesari E, Farini D, Medici V, Ehrmann I, Guerra M, Testa E, Naro C, Geloso MC, Pagliarini V, La Barbera L, D’Amelio M, Orsini T, Vecchioli SF, Tamagnone L, Fort P, Viscomi MT, Elliott DJ, Sette C. Differential expression of paralog RNA binding proteins establishes a dynamic splicing program required for normal cerebral cortex development. Nucleic Acids Res 2024; 52:4167-4184. [PMID: 38324473 PMCID: PMC11077083 DOI: 10.1093/nar/gkae071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 01/17/2024] [Accepted: 01/25/2024] [Indexed: 02/09/2024] Open
Abstract
Sam68 and SLM2 are paralog RNA binding proteins (RBPs) expressed in the cerebral cortex and display similar splicing activities. However, their relative functions during cortical development are unknown. We found that these RBPs exhibit an opposite expression pattern during development. Sam68 expression declines postnatally while SLM2 increases after birth, and this developmental pattern is reinforced by hierarchical control of Sam68 expression by SLM2. Analysis of Sam68:Slm2 double knockout (Sam68:Slm2dko) mice revealed hundreds of exons that respond to joint depletion of these proteins. Moreover, parallel analysis of single and double knockout cortices indicated that exons regulated mainly by SLM2 are characterized by a dynamic splicing pattern during development, whereas Sam68-dependent exons are spliced at relatively constant rates. Dynamic splicing of SLM2-sensitive exons is completely suppressed in the Sam68:Slm2dko developing cortex. Sam68:Slm2dko mice die perinatally with defects in neurogenesis and in neuronal differentiation, and develop a hydrocephalus, consistent with splicing alterations in genes related to these biological processes. Thus, our study reveals that developmental control of separate Sam68 and Slm2 paralog genes encoding homologous RBPs enables the orchestration of a dynamic splicing program needed for brain development and viability, while ensuring a robust redundant mechanism that supports proper cortical development.
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Affiliation(s)
- Eleonora Cesari
- Department of Neuroscience, Section of Human Anatomy, Catholic University of the Sacred Heart, Largo Francesco Vito 1, 00168 Rome, Italy
- Fondazione Policlinico Agostino Gemelli IRCCS, Largo Agostino Gemelli, 00168 Rome, Italy
| | - Donatella Farini
- Department of Biomedicine and Prevention, University of Rome Tor Vergata, Via Montpellier 1, 00133 Rome, Italy
- Fondazione Santa Lucia IRCCS, Via del Fosso di Fiorano, 64, 00143 Rome, Italy
| | - Vanessa Medici
- Department of Neuroscience, Section of Human Anatomy, Catholic University of the Sacred Heart, Largo Francesco Vito 1, 00168 Rome, Italy
| | - Ingrid Ehrmann
- Newcastle University Centre for Cancer, Newcastle University Institute of Biosciences, Newcastle NE1 3BZ, UK
| | - Marika Guerra
- Department of Neuroscience, Section of Human Anatomy, Catholic University of the Sacred Heart, Largo Francesco Vito 1, 00168 Rome, Italy
| | - Erika Testa
- Department of Life Science and Public Health, Section of Histology and Embryology, Catholic University of the Sacred Heart, Rome
| | - Chiara Naro
- Department of Neuroscience, Section of Human Anatomy, Catholic University of the Sacred Heart, Largo Francesco Vito 1, 00168 Rome, Italy
- Fondazione Policlinico Agostino Gemelli IRCCS, Largo Agostino Gemelli, 00168 Rome, Italy
| | - Maria Concetta Geloso
- Department of Neuroscience, Section of Human Anatomy, Catholic University of the Sacred Heart, Largo Francesco Vito 1, 00168 Rome, Italy
| | - Vittoria Pagliarini
- Department of Neuroscience, Section of Human Anatomy, Catholic University of the Sacred Heart, Largo Francesco Vito 1, 00168 Rome, Italy
- Fondazione Policlinico Agostino Gemelli IRCCS, Largo Agostino Gemelli, 00168 Rome, Italy
| | - Livia La Barbera
- Fondazione Santa Lucia IRCCS, Via del Fosso di Fiorano, 64, 00143 Rome, Italy
| | - Marcello D’Amelio
- Fondazione Santa Lucia IRCCS, Via del Fosso di Fiorano, 64, 00143 Rome, Italy
- Università Campus Bio-Medico di Roma, Via Álvaro del Portillo, 21, 00128 Rome, Italy
| | - Tiziana Orsini
- Institute of Biochemistry and Cell Biology, National Research Council (IBBC/CNR), Monterotondo, 00015 Rome, Italy
| | - Stefano Farioli Vecchioli
- Institute of Biochemistry and Cell Biology, National Research Council (IBBC/CNR), Monterotondo, 00015 Rome, Italy
| | - Luca Tamagnone
- Fondazione Policlinico Agostino Gemelli IRCCS, Largo Agostino Gemelli, 00168 Rome, Italy
- Department of Life Science and Public Health, Section of Histology and Embryology, Catholic University of the Sacred Heart, Rome
| | - Philippe Fort
- Centre de Recherche en Biologie Cellulaire de Montpellier, University of Montpellier, CNRS, 1919 Route de Mende, 34293 Montpellier Cedex 05, France
| | - Maria Teresa Viscomi
- Fondazione Policlinico Agostino Gemelli IRCCS, Largo Agostino Gemelli, 00168 Rome, Italy
- Department of Life Science and Public Health, Section of Histology and Embryology, Catholic University of the Sacred Heart, Rome
| | - David J Elliott
- Newcastle University Centre for Cancer, Newcastle University Institute of Biosciences, Newcastle NE1 3BZ, UK
| | - Claudio Sette
- Department of Neuroscience, Section of Human Anatomy, Catholic University of the Sacred Heart, Largo Francesco Vito 1, 00168 Rome, Italy
- Fondazione Policlinico Agostino Gemelli IRCCS, Largo Agostino Gemelli, 00168 Rome, Italy
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2
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Verdile V, Palombo R, Ferrante G, Ferri A, Amadio S, Volonté C, Paronetto MP. Dysregulation of alternative splicing underlies synaptic defects in familial amyotrophic lateral sclerosis. Prog Neurobiol 2023; 231:102529. [PMID: 37739207 DOI: 10.1016/j.pneurobio.2023.102529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 09/11/2023] [Accepted: 09/17/2023] [Indexed: 09/24/2023]
Abstract
Amyotrophic lateral sclerosis (ALS) is an incurable neurodegenerative disease characterized by the degeneration of upper and lower motor neurons, progressive wasting and paralysis of voluntary muscles. A hallmark of ALS is the frequent nuclear loss and cytoplasmic accumulation of RNA binding proteins (RBPs) in motor neurons (MN), which leads to aberrant alternative splicing regulation. However, whether altered splicing patterns are also present in familial models of ALS without mutations in RBP-encoding genes has not been investigated yet. Herein, we found that altered splicing of synaptic genes is a common trait of familial ALS MNs. Similar deregulation was also observed in hSOD1G93A MN-like cells. In silico analysis identified the potential regulators of these pre-mRNAs, including the RBP Sam68. Immunofluorescence analysis and biochemical fractionation experiments revealed that Sam68 accumulates in the cytoplasmic insoluble ribonucleoprotein fraction of MN. Remarkably, the synaptic splicing events deregulated in ALS MNs were also affected in Sam68-/- spinal cords. Recombinant expression of Sam68 protein was sufficient to rescue these splicing changes in ALS hSOD1G93A MN-like cells. Hence, our study highlights an aberrant function of Sam68, which leads to splicing changes in synaptic genes and may contribute to the MN phenotype that characterizes ALS.
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Affiliation(s)
- Veronica Verdile
- Department of Movement, Human and Health Sciences, University of Rome "Foro Italico", Piazza Lauro de Bosis 6, 00135 Rome, Italy; Division of Experimental Neuroscience, IRCCS Fondazione Santa Lucia, Via del Fosso di Fiorano 64, Rome 00143, Italy
| | - Ramona Palombo
- Department of Movement, Human and Health Sciences, University of Rome "Foro Italico", Piazza Lauro de Bosis 6, 00135 Rome, Italy
| | - Gabriele Ferrante
- Division of Experimental Neuroscience, IRCCS Fondazione Santa Lucia, Via del Fosso di Fiorano 64, Rome 00143, Italy
| | - Alberto Ferri
- Division of Experimental Neuroscience, IRCCS Fondazione Santa Lucia, Via del Fosso di Fiorano 64, Rome 00143, Italy; National Research Council (CNR), Institute of Translational Pharmacology (IFT), Rome, Italy
| | - Susanna Amadio
- Division of Experimental Neuroscience, IRCCS Fondazione Santa Lucia, Via del Fosso di Fiorano 64, Rome 00143, Italy
| | - Cinzia Volonté
- Division of Experimental Neuroscience, IRCCS Fondazione Santa Lucia, Via del Fosso di Fiorano 64, Rome 00143, Italy; National Research Council (CNR), Institute for Systems Analysis and Computer Science (IASI), Rome, Italy
| | - Maria Paola Paronetto
- Department of Movement, Human and Health Sciences, University of Rome "Foro Italico", Piazza Lauro de Bosis 6, 00135 Rome, Italy; Division of Experimental Neuroscience, IRCCS Fondazione Santa Lucia, Via del Fosso di Fiorano 64, Rome 00143, Italy.
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3
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Traunmüller L, Schulz J, Ortiz R, Feng H, Furlanis E, Gomez AM, Schreiner D, Bischofberger J, Zhang C, Scheiffele P. A cell-type-specific alternative splicing regulator shapes synapse properties in a trans-synaptic manner. Cell Rep 2023; 42:112173. [PMID: 36862556 PMCID: PMC10066595 DOI: 10.1016/j.celrep.2023.112173] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Revised: 12/07/2022] [Accepted: 02/12/2023] [Indexed: 03/03/2023] Open
Abstract
The specification of synaptic properties is fundamental for the function of neuronal circuits. "Terminal selector" transcription factors coordinate terminal gene batteries that specify cell-type-specific properties. Moreover, pan-neuronal splicing regulators have been implicated in directing neuronal differentiation. However, the cellular logic of how splicing regulators instruct specific synaptic properties remains poorly understood. Here, we combine genome-wide mapping of mRNA targets and cell-type-specific loss-of-function studies to uncover the contribution of the RNA-binding protein SLM2 to hippocampal synapse specification. Focusing on pyramidal cells and somatostatin (SST)-positive GABAergic interneurons, we find that SLM2 preferentially binds and regulates alternative splicing of transcripts encoding synaptic proteins. In the absence of SLM2, neuronal populations exhibit normal intrinsic properties, but there are non-cell-autonomous synaptic phenotypes and associated defects in a hippocampus-dependent memory task. Thus, alternative splicing provides a critical layer of gene regulation that instructs specification of neuronal connectivity in a trans-synaptic manner.
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Affiliation(s)
| | - Jan Schulz
- Department of Biomedicine, University of Basel, 4056 Basel, Switzerland
| | - Raul Ortiz
- Biozentrum of the University of Basel, 4056 Basel, Switzerland
| | - Huijuan Feng
- Department of Systems Biology, Department of Biochemistry and Molecular Biophysics, Center for Motor Neuron Biology and Disease, Columbia University, New York, NY 10032, USA
| | | | - Andrea M Gomez
- Biozentrum of the University of Basel, 4056 Basel, Switzerland
| | | | | | - Chaolin Zhang
- Department of Systems Biology, Department of Biochemistry and Molecular Biophysics, Center for Motor Neuron Biology and Disease, Columbia University, New York, NY 10032, USA
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4
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Adinolfi A, Di Sante G, Rivignani Vaccari L, Tredicine M, Ria F, Bonvissuto D, Corvino V, Sette C, Geloso MC. Regionally restricted modulation of Sam68 expression and Arhgef9 alternative splicing in the hippocampus of a murine model of multiple sclerosis. Front Mol Neurosci 2023; 15:1073627. [PMID: 36710925 PMCID: PMC9878567 DOI: 10.3389/fnmol.2022.1073627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Accepted: 12/21/2022] [Indexed: 01/15/2023] Open
Abstract
Multiple sclerosis (MS) and its preclinical models are characterized by marked changes in neuroplasticity, including excitatory/inhibitory imbalance and synaptic dysfunction that are believed to underlie the progressive cognitive impairment (CI), which represents a significant clinical hallmark of the disease. In this study, we investigated several parameters of neuroplasticity in the hippocampus of the experimental autoimmune encephalomyelitis (EAE) SJL/J mouse model, characterized by rostral inflammatory and demyelinating lesions similar to Relapsing-Remitting MS. By combining morphological and molecular analyses, we found that the hippocampus undergoes extensive inflammation in EAE-mice, more pronounced in the CA3 and dentate gyrus (DG) subfields than in the CA1, associated with changes in GABAergic circuitry, as indicated by the increased expression of the interneuron marker Parvalbumin selectively in CA3. By laser-microdissection, we investigated the impact of EAE on the alternative splicing of Arhgef9, a gene encoding a post-synaptic protein playing an essential role in GABAergic synapses and whose mutations have been related to CI and epilepsy. Our results indicate that EAE induces a specific increase in inclusion of the alternative exon 11a only in the CA3 and DG subfields, in line with the higher local levels of inflammation. Consistently, we found a region-specific downregulation of Sam68, a splicing-factor that represses this splicing event. Collectively, our findings confirm a regionalized distribution of inflammation in the hippocampus of EAE-mice. Moreover, since neuronal circuit rearrangement and dynamic remodeling of structural components of the synapse are key processes that contribute to neuroplasticity, our study suggests potential new molecular players involved in EAE-induced hippocampal dysfunction.
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Affiliation(s)
- Annalisa Adinolfi
- Section of Human Anatomy, Department of Neuroscience, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Gabriele Di Sante
- Section of Human, Clinic and Forensic Anatomy, Department of Medicine and Surgery, University of Perugia, Perugia, Italy
| | - Luca Rivignani Vaccari
- Section of Human Anatomy, Department of Neuroscience, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Maria Tredicine
- Section of General Pathology, Department of Translational Medicine and Surgery, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Francesco Ria
- Section of General Pathology, Department of Translational Medicine and Surgery, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Davide Bonvissuto
- Section of Human Anatomy, Department of Neuroscience, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Valentina Corvino
- Section of Human Anatomy, Department of Neuroscience, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Claudio Sette
- Section of Human Anatomy, Department of Neuroscience, Università Cattolica del Sacro Cuore, Rome, Italy,GSTEP-Organoids Core Facility, Fondazione Policlinico Agostino Gemelli IRCCS, Rome, Italy,*Correspondence: Claudio Sette, ✉
| | - Maria Concetta Geloso
- Section of Human Anatomy, Department of Neuroscience, Università Cattolica del Sacro Cuore, Rome, Italy,Maria Concetta Geloso, ✉
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5
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Automated Image Analysis Reveals Different Localization of Synaptic Gephyrin C4 Splice Variants. eNeuro 2023; 10:ENEURO.0102-22.2022. [PMID: 36543537 PMCID: PMC9831149 DOI: 10.1523/eneuro.0102-22.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2022] [Revised: 11/12/2022] [Accepted: 12/13/2022] [Indexed: 12/24/2022] Open
Abstract
Postsynaptic scaffolding proteins function as central organization hubs, ensuring the synaptic localization of neurotransmitter receptors, trans-synaptic adhesion proteins, and signaling molecules. Gephyrin is the major postsynaptic scaffolding protein at glycinergic and a subset of GABAergic inhibitory synapses. In contrast to cells outside the CNS, where one gephyrin isoform is predominantly expressed, neurons express different splice variants. In this study, we characterized the expression and scaffolding of neuronal gephyrin isoforms differing in the inclusion of the C4 cassettes located in the central C-domain. In hippocampal and cortical neuronal populations, gephyrin P1, lacking additional cassettes, is the most abundantly expressed isoform. In addition, alternative splicing generated isoforms carrying predominantly C4a, and minor amounts of C4c or C4d cassettes. We detected no striking difference in C4 isoform expression between different neuron types and a single neuron can likely express all C4 isoforms. To avoid the cytosolic aggregates that are commonly observed upon exogenous gephyrin expression, we used adeno-associated virus (AAV)-mediated expression to analyze the scaffolding behavior of individual C4 isoforms in murine dissociated hippocampal glutamatergic neurons. While all isoforms showed similar clustering at GABAergic synapses, a thorough quantitative analysis revealed localization differences for the C4c isoform (also known as P2). Specifically, synaptic C4c isoform clusters showed a more distal dendritic localization and reduced occurrence at P1-predominating synapses. Additionally, inhibitory currents displayed faster decay kinetics in the presence of gephyrin C4c compared with P1. Therefore, inhibitory synapse heterogeneity may be influenced, at least in part, by mechanisms relating to C4 cassette splicing.
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Landínez-Macías M, Urwyler O. The Fine Art of Writing a Message: RNA Metabolism in the Shaping and Remodeling of the Nervous System. Front Mol Neurosci 2021; 14:755686. [PMID: 34916907 PMCID: PMC8670310 DOI: 10.3389/fnmol.2021.755686] [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: 08/09/2021] [Accepted: 10/18/2021] [Indexed: 01/25/2023] Open
Abstract
Neuronal morphogenesis, integration into circuits, and remodeling of synaptic connections occur in temporally and spatially defined steps. Accordingly, the expression of proteins and specific protein isoforms that contribute to these processes must be controlled quantitatively in time and space. A wide variety of post-transcriptional regulatory mechanisms, which act on pre-mRNA and mRNA molecules contribute to this control. They are thereby critically involved in physiological and pathophysiological nervous system development, function, and maintenance. Here, we review recent findings on how mRNA metabolism contributes to neuronal development, from neural stem cell maintenance to synapse specification, with a particular focus on axon growth, guidance, branching, and synapse formation. We emphasize the role of RNA-binding proteins, and highlight their emerging roles in the poorly understood molecular processes of RNA editing, alternative polyadenylation, and temporal control of splicing, while also discussing alternative splicing, RNA localization, and local translation. We illustrate with the example of the evolutionary conserved Musashi protein family how individual RNA-binding proteins are, on the one hand, acting in different processes of RNA metabolism, and, on the other hand, impacting multiple steps in neuronal development and circuit formation. Finally, we provide links to diseases that have been associated with the malfunction of RNA-binding proteins and disrupted post-transcriptional regulation.
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Affiliation(s)
- María Landínez-Macías
- Department of Molecular Life Sciences, University of Zurich, Zurich, Switzerland.,Molecular Life Sciences Program, Life Science Zurich Graduate School, University of Zurich and Eidgenössische Technische Hochschule (ETH) Zurich, Zurich, Switzerland
| | - Olivier Urwyler
- Department of Molecular Life Sciences, University of Zurich, Zurich, Switzerland.,Molecular Life Sciences Program, Life Science Zurich Graduate School, University of Zurich and Eidgenössische Technische Hochschule (ETH) Zurich, Zurich, Switzerland.,Neuroscience Center Zurich (ZNZ), University of Zurich, Zurich, Switzerland
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7
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Fukai S, Yoshida T. Roles of type IIa receptor protein tyrosine phosphatases as synaptic organizers. FEBS J 2020; 288:6913-6926. [PMID: 33301645 DOI: 10.1111/febs.15666] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 11/26/2020] [Accepted: 12/08/2020] [Indexed: 12/14/2022]
Abstract
Neurons establish circuits for brain functions such as cognition, emotion, learning, and memory. Their connections are mediated by synapses, which are specialized cell-cell adhesions responsible for neuronal signal transmission. During neurodevelopment, synapse formation is triggered by interactions of cell adhesion molecules termed synaptic organizers or synapse organizers. Type IIa receptor protein tyrosine phosphatases (IIa RPTPs; also known as leukocyte common antigen-related receptor tyrosine phosphatases or LAR-RPTPs) play important roles in axon guidance and neurite extension, and also serve as presynaptic organizers. IIa RPTPs transsynaptically interact with multiple sets of postsynaptic organizers, mostly in a splicing-dependent fashion. Here, we review and update research progress on IIa RPTPs, particularly regarding their functional roles in vivo demonstrated using conditional knockout approach and structural insights into their extracellular and intracellular molecular interactions revealed by crystallography and other biophysical techniques. Future directions in the research field of IIa RPTPs are also discussed, including recent findings of the molecular assembly mechanism underlying the formation of synapse-specific nanostructures essential for synaptic functions.
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Affiliation(s)
- Shuya Fukai
- Department of Chemistry, Graduate School of Science, Kyoto University, Japan
| | - Tomoyuki Yoshida
- Department of Molecular Neuroscience, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Japan
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8
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De Paola E, Forcina L, Pelosi L, Pisu S, La Rosa P, Cesari E, Nicoletti C, Madaro L, Mercatelli N, Biamonte F, Nobili A, D'Amelio M, De Bardi M, Volpe E, Caporossi D, Sette C, Musarò A, Paronetto MP. Sam68 splicing regulation contributes to motor unit establishment in the postnatal skeletal muscle. Life Sci Alliance 2020; 3:3/10/e201900637. [PMID: 32753528 PMCID: PMC7409371 DOI: 10.26508/lsa.201900637] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Revised: 07/23/2020] [Accepted: 07/24/2020] [Indexed: 01/08/2023] Open
Abstract
Sam68 ensures the establishment of neuromuscular junctions (NMJs) and motor unit integrity by orchestrating a neuronal splicing program. RNA-binding proteins orchestrate the composite life of RNA molecules and impact most physiological processes, thus underlying complex phenotypes. The RNA-binding protein Sam68 regulates differentiation processes by modulating splicing, polyadenylation, and stability of select transcripts. Herein, we found that Sam68−/− mice display altered regulation of alternative splicing in the spinal cord of key target genes involved in synaptic functions. Analysis of the motor units revealed that Sam68 ablation impairs the establishment of neuromuscular junctions and causes progressive loss of motor neurons in the spinal cord. Importantly, alterations of neuromuscular junction morphology and properties in Sam68−/− mice correlate with defects in muscle and motor unit integrity. Sam68−/− muscles display defects in postnatal development, with manifest signs of atrophy. Furthermore, fast-twitch muscles in Sam68−/− mice show structural features typical of slow-twitch muscles, suggesting alterations in the metabolic and functional properties of myofibers. Collectively, our data identify a key role for Sam68 in muscle development and suggest that proper establishment of motor units requires timely expression of synaptic splice variants.
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Affiliation(s)
- Elisa De Paola
- Department of Movement, Human and Health Sciences, University of Rome "Foro Italico," Rome, Italy.,IRCCS (Institute for Treatment and Research) Fondazione Santa Lucia, Rome, Italy
| | - Laura Forcina
- Laboratory Affiliated to Istituto Pasteur-Fondazione Cenci Bolognetti, DAHFMO-Unit of Histology and Medical Embryology, Sapienza University of Rome, Rome, Italy
| | - Laura Pelosi
- Laboratory Affiliated to Istituto Pasteur-Fondazione Cenci Bolognetti, DAHFMO-Unit of Histology and Medical Embryology, Sapienza University of Rome, Rome, Italy
| | - Simona Pisu
- Laboratory Affiliated to Istituto Pasteur-Fondazione Cenci Bolognetti, DAHFMO-Unit of Histology and Medical Embryology, Sapienza University of Rome, Rome, Italy
| | - Piergiorgio La Rosa
- IRCCS (Institute for Treatment and Research) Fondazione Santa Lucia, Rome, Italy
| | - Eleonora Cesari
- IRCCS (Institute for Treatment and Research) Fondazione Santa Lucia, Rome, Italy.,Institute of Human Anatomy and Cell Biology, Catholic University of the Sacred Heart, Rome, Italy
| | - Carmine Nicoletti
- Laboratory Affiliated to Istituto Pasteur-Fondazione Cenci Bolognetti, DAHFMO-Unit of Histology and Medical Embryology, Sapienza University of Rome, Rome, Italy
| | - Luca Madaro
- Institute of Human Anatomy and Cell Biology, Catholic University of the Sacred Heart, Rome, Italy
| | - Neri Mercatelli
- Department of Movement, Human and Health Sciences, University of Rome "Foro Italico," Rome, Italy.,IRCCS (Institute for Treatment and Research) Fondazione Santa Lucia, Rome, Italy
| | - Filippo Biamonte
- Institute of Biochemistry and Clinical Biochemistry, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
| | - Annalisa Nobili
- IRCCS (Institute for Treatment and Research) Fondazione Santa Lucia, Rome, Italy.,Department of Medicine, University Campus-Biomedico, Rome, Italy
| | - Marcello D'Amelio
- IRCCS (Institute for Treatment and Research) Fondazione Santa Lucia, Rome, Italy.,Department of Medicine, University Campus-Biomedico, Rome, Italy
| | - Marco De Bardi
- IRCCS (Institute for Treatment and Research) Fondazione Santa Lucia, Rome, Italy
| | - Elisabetta Volpe
- IRCCS (Institute for Treatment and Research) Fondazione Santa Lucia, Rome, Italy
| | - Daniela Caporossi
- Department of Movement, Human and Health Sciences, University of Rome "Foro Italico," Rome, Italy
| | - Claudio Sette
- IRCCS (Institute for Treatment and Research) Fondazione Santa Lucia, Rome, Italy .,Institute of Human Anatomy and Cell Biology, Catholic University of the Sacred Heart, Rome, Italy
| | - Antonio Musarò
- Laboratory Affiliated to Istituto Pasteur-Fondazione Cenci Bolognetti, DAHFMO-Unit of Histology and Medical Embryology, Sapienza University of Rome, Rome, Italy
| | - Maria Paola Paronetto
- Department of Movement, Human and Health Sciences, University of Rome "Foro Italico," Rome, Italy .,IRCCS (Institute for Treatment and Research) Fondazione Santa Lucia, Rome, Italy
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9
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Campbell BFN, Tyagarajan SK. Cellular Mechanisms Contributing to the Functional Heterogeneity of GABAergic Synapses. Front Mol Neurosci 2019; 12:187. [PMID: 31456660 PMCID: PMC6700328 DOI: 10.3389/fnmol.2019.00187] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Accepted: 07/19/2019] [Indexed: 11/24/2022] Open
Abstract
GABAergic inhibitory neurotransmission contributes to diverse aspects of brain development and adult plasticity, including the expression of complex cognitive processes. This is afforded for in part by the dynamic adaptations occurring at inhibitory synapses, which show great heterogeneity both in terms of upstream signaling and downstream effector mechanisms. Single-particle tracking and live imaging have revealed that complex receptor-scaffold interactions critically determine adaptations at GABAergic synapses. Super-resolution imaging studies have shown that protein interactions at synaptic sites contribute to nano-scale scaffold re-arrangements through post-translational modifications (PTMs), facilitating receptor and scaffold recruitment to synaptic sites. Additionally, plasticity mechanisms may be affected by the protein composition at individual synapses and the type of pre-synaptic input. This mini-review article examines recent discoveries of plasticity mechanisms that are operational within GABAergic synapses and discusses their contribution towards functional heterogeneity in inhibitory neurotransmission.
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Affiliation(s)
| | - Shiva K Tyagarajan
- Institute of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland
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10
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Que L, Winterer J, Földy C. Deep Survey of GABAergic Interneurons: Emerging Insights From Gene-Isoform Transcriptomics. Front Mol Neurosci 2019; 12:115. [PMID: 31133800 PMCID: PMC6514532 DOI: 10.3389/fnmol.2019.00115] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Accepted: 04/23/2019] [Indexed: 11/13/2022] Open
Abstract
GABAergic interneuron diversity is a key feature in the brain that helps to create different brain activity patterns and behavioral states. Cell type classification schemes—based on anatomical, physiological and molecular features—have provided us with a detailed understanding of the distinct types that constitute this diversity and their contribution to brain function. Over recent years, the utility of single-cell RNAseq has majorly complemented this existing framework, vastly expanding our knowledge base, particularly regarding molecular features. Single-cell gene-expression profiles of tens of thousands of GABAergic cells from many different types are now available. The analysis of these data has shed new lights onto previous classification principles and illuminates a path towards a deeper understanding of molecular hallmarks behind interneuron diversity. A large part of such molecular features is synapse-related. These include ion channels and receptors, as well as key synaptic organizers and trans-synaptic signaling molecules. Increasing evidence suggests that transcriptional and post-transcriptional modifications further diversify these molecules and generate cell type-specific features. Thus, unraveling the cell type-specific nature of gene-isoform expression will be a key in cell type classification. This review article discusses progress in the transcriptomic survey of interneurons and insights that have begun to manifest from isoform-level analyses.
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Affiliation(s)
- Lin Que
- Laboratory of Neural Connectivity, Faculties of Medicine and Natural Sciences, Brain Research Institute, University of Zurich, Zurich, Switzerland
| | - Jochen Winterer
- Laboratory of Neural Connectivity, Faculties of Medicine and Natural Sciences, Brain Research Institute, University of Zurich, Zurich, Switzerland
| | - Csaba Földy
- Laboratory of Neural Connectivity, Faculties of Medicine and Natural Sciences, Brain Research Institute, University of Zurich, Zurich, Switzerland
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