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Artimagnella O, Maftei ES, Esposito M, Sanges R, Mallamaci A. Foxg1 regulates translation of neocortical neuronal genes, including the main NMDA receptor subunit gene, Grin1. BMC Biol 2024; 22:180. [PMID: 39183266 PMCID: PMC11346056 DOI: 10.1186/s12915-024-01979-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Accepted: 08/12/2024] [Indexed: 08/27/2024] Open
Abstract
BACKGROUND Mainly known as a transcription factor patterning the rostral brain and governing its histogenesis, FOXG1 has been also detected outside the nucleus; however, biological meaning of that has been only partially clarified. RESULTS Prompted by FOXG1 expression in cytoplasm of pallial neurons, we investigated its implication in translational control. We documented the impact of FOXG1 on ribosomal recruitment of Grin1-mRNA, encoding for the main subunit of NMDA receptor. Next, we showed that FOXG1 increases GRIN1 protein level by enhancing the translation of its mRNA, while not increasing its stability. Molecular mechanisms underlying this activity included FOXG1 interaction with EIF4E and, possibly, Grin1-mRNA. Besides, we found that, within murine neocortical cultures, de novo synthesis of GRIN1 undergoes a prominent and reversible, homeostatic regulation and FOXG1 is instrumental to that. Finally, by integrated analysis of multiple omic data, we inferred that FOXG1 is implicated in translational control of hundreds of neuronal genes, modulating ribosome engagement and progression. In a few selected cases, we experimentally verified such inference. CONCLUSIONS These findings point to FOXG1 as a key effector, potentially crucial to multi-scale temporal tuning of neocortical pyramid activity, an issue with profound physiological and neuropathological implications.
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Affiliation(s)
- Osvaldo Artimagnella
- Laboratory of Cerebral Cortex Development, SISSA, Via Bonomea 265, 34136, Trieste, Italy
- Present Address: IRCCS Centro Neurolesi "Bonino-Pulejo", Messina, Italy
| | - Elena Sabina Maftei
- Laboratory of Cerebral Cortex Development, SISSA, Via Bonomea 265, 34136, Trieste, Italy
| | - Mauro Esposito
- Laboratory of Computational Genomics, SISSA, via Bonomea 265, 34136, Trieste, Italy
- Present Address: Neomatrix SRL, Rome, Italy
| | - Remo Sanges
- Laboratory of Computational Genomics, SISSA, via Bonomea 265, 34136, Trieste, Italy
| | - Antonello Mallamaci
- Laboratory of Cerebral Cortex Development, SISSA, Via Bonomea 265, 34136, Trieste, Italy.
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Sibarov DA, Tsytsarev V, Volnova A, Vaganova AN, Alves J, Rojas L, Sanabria P, Ignashchenkova A, Savage ED, Inyushin M. Arc protein, a remnant of ancient retrovirus, forms virus-like particles, which are abundantly generated by neurons during epileptic seizures, and affects epileptic susceptibility in rodent models. Front Neurol 2023; 14:1201104. [PMID: 37483450 PMCID: PMC10361770 DOI: 10.3389/fneur.2023.1201104] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Accepted: 06/02/2023] [Indexed: 07/25/2023] Open
Abstract
A product of the immediate early gene Arc (Activity-regulated cytoskeleton-associated protein or Arc protein) of retroviral ancestry resides in the genome of all tetrapods for millions of years and is expressed endogenously in neurons. It is a well-known protein, very important for synaptic plasticity and memory consolidation. Activity-dependent Arc expression concentrated in glutamatergic synapses affects the long-time synaptic strength of those excitatory synapses. Because it modulates excitatory-inhibitory balance in a neuronal network, the Arc gene itself was found to be related to the pathogenesis of epilepsy. General Arc knockout rodent models develop a susceptibility to epileptic seizures. Because of activity dependence, synaptic Arc protein synthesis also is affected by seizures. Interestingly, it was found that Arc protein in synapses of active neurons self-assemble in capsids of retrovirus-like particles, which can transfer genetic information between neurons, at least across neuronal synaptic boutons. Released Arc particles can be accumulated in astrocytes after seizures. It is still not known how capsid assembling and transmission timescale is affected by seizures. This scientific field is relatively novel and is experiencing swift transformation as it grapples with difficult concepts in light of evolving experimental findings. We summarize the emergent literature on the subject and also discuss the specific rodent models for studying Arc effects in epilepsy. We summarized both to clarify the possible role of Arc-related pseudo-viral particles in epileptic disorders, which may be helpful to researchers interested in this growing area of investigation.
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Affiliation(s)
- Dmitry A. Sibarov
- Sechenov Institute of Evolutionary Physiology and Biochemistry of the Russian Academy of Sciences, Saint Petersburg, Russia
| | - Vassiliy Tsytsarev
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Anna Volnova
- Institute of Translational Biomedicine, Saint Petersburg State University, Saint Petersburg, Russia
| | - Anastasia N. Vaganova
- Institute of Translational Biomedicine, Saint Petersburg State University, Saint Petersburg, Russia
| | - Janaina Alves
- School of Medicine, Universidad Central del Caribe, Bayamón, PR, United States
| | - Legier Rojas
- School of Medicine, Universidad Central del Caribe, Bayamón, PR, United States
| | - Priscila Sanabria
- School of Medicine, Universidad Central del Caribe, Bayamón, PR, United States
| | | | | | - Mikhail Inyushin
- School of Medicine, Universidad Central del Caribe, Bayamón, PR, United States
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3
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Mahringer D, Zmarz P, Okuno H, Bito H, Keller GB. Functional correlates of immediate early gene expression in mouse visual cortex. PEER COMMUNITY JOURNAL 2022; 2:e45. [PMID: 37091727 PMCID: PMC7614465 DOI: 10.24072/pcjournal.156] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 04/25/2023]
Abstract
During visual development, response properties of layer 2/3 neurons in visual cortex are shaped by experience. Both visual and visuomotor experience are necessary to co-ordinate the integration of bottom-up visual input and top-down motor-related input. Whether visual and visuomotor experience engage different plasticity mechanisms, possibly associated with the two separate input pathways, is still unclear. To begin addressing this, we measured the expression level of three different immediate early genes (IEG) (c-fos, egr1 or Arc) and neuronal activity in layer 2/3 neurons of visual cortex before and after a mouse's first visual exposure in life, and subsequent visuomotor learning. We found that expression levels of all three IEGs correlated positively with neuronal activity, but that first visual and first visuomotor exposure resulted in differential changes in IEG expression patterns. In addition, IEG expression levels differed depending on whether neurons exhibited primarily visually driven or motor-related activity. Neurons with strong motor-related activity preferentially expressed EGR1, while neurons that developed strong visually driven activity preferentially expressed Arc. Our findings are consistent with the interpretation that bottom-up visual input and top-down motor-related input are associated with different IEG expression patterns and hence possibly also with different plasticity pathways.
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Affiliation(s)
- David Mahringer
- Faculty of Natural Sciences, University of Basel, Basel, Switzerland
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Pawel Zmarz
- Faculty of Natural Sciences, University of Basel, Basel, Switzerland
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Hiroyuki Okuno
- Department of Biochemistry and Molecular Biology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Kagoshima 890-8544, Japan
| | - Haruhiko Bito
- Department of Neurochemistry, Graduate School of Medicine, The University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Georg B Keller
- Faculty of Natural Sciences, University of Basel, Basel, Switzerland
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
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mRNA Trafficking in the Nervous System: A Key Mechanism of the Involvement of Activity-Regulated Cytoskeleton-Associated Protein (Arc) in Synaptic Plasticity. Neural Plast 2021; 2021:3468795. [PMID: 34603440 PMCID: PMC8486535 DOI: 10.1155/2021/3468795] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 08/15/2021] [Accepted: 09/07/2021] [Indexed: 12/18/2022] Open
Abstract
Synaptic activity mediates information storage and memory consolidation in the brain and requires a fast de novo synthesis of mRNAs in the nucleus and proteins in synapses. Intracellular localization of a protein can be achieved by mRNA trafficking and localized translation. Activity-regulated cytoskeleton-associated protein (Arc) is a master regulator of synaptic plasticity and plays an important role in controlling large signaling networks implicated in learning, memory consolidation, and behavior. Transcription of the Arc gene may be induced by a short behavioral event, resulting in synaptic activation. Arc mRNA is exported into the cytoplasm and can be trafficked into the dendrite of an activated synapse where it is docked and translated. The structure of Arc is similar to the viral GAG (group-specific antigen) protein, and phylogenic analysis suggests that Arc may originate from the family of Ty3/Gypsy retrotransposons. Therefore, Arc might evolve through “domestication” of retroviruses. Arc can form a capsid-like structure that encapsulates a retrovirus-like sentence in the 3′-UTR (untranslated region) of Arc mRNA. Such complex can be loaded into extracellular vesicles and transported to other neurons or muscle cells carrying not only genetic information but also regulatory signals within neuronal networks. Therefore, Arc mRNA inter- and intramolecular trafficking is essential for the modulation of synaptic activity required for memory consolidation and cognitive functions. Recent studies with single-molecule imaging in live neurons confirmed and extended the role of Arc mRNA trafficking in synaptic plasticity.
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5
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Secreted Reporter Assay Enables Quantitative and Longitudinal Monitoring of Neuronal Activity. eNeuro 2021; 8:ENEURO.0518-20.2021. [PMID: 34531280 PMCID: PMC8489021 DOI: 10.1523/eneuro.0518-20.2021] [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: 11/30/2020] [Revised: 08/23/2021] [Accepted: 09/08/2021] [Indexed: 11/21/2022] Open
Abstract
The ability to measure changes in neuronal activity in a quantifiable and precise manner is of fundamental importance to understand neuron development and function. Repeated monitoring of neuronal activity of the same population of neurons over several days is challenging and, typically, low-throughput. Here, we describe a new biochemical reporter assay that allows for repeated measurements of neuronal activity in a cell type-specific manner. We coupled activity-dependent elements from the Arc/Arg3.1 gene with a secreted reporter, Gaussia luciferase (Gluc), to quantify neuronal activity without sacrificing the neurons. The reporter predominantly senses calcium and NMDA receptor (NMDAR)-dependent activity. By repeatedly measuring the accumulation of the reporter in cell media, we can profile the developmental dynamics of neuronal activity in cultured neurons from male and female mice. The assay also allows for longitudinal analysis of pharmacological treatments, thus distinguishing acute from delayed responses. Moreover, conditional expression of the reporter allows for monitoring cell type-specific changes. This simple, quantitative, cost-effective, automatable, and cell type-specific activity reporter is a valuable tool to study the development of neuronal activity in normal and disease-model conditions, and to identify small molecules or protein factors that selectively modulate the activity of a specific population of neurons.
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6
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UPF2 leads to degradation of dendritically targeted mRNAs to regulate synaptic plasticity and cognitive function. Mol Psychiatry 2020; 25:3360-3379. [PMID: 31636381 PMCID: PMC7566522 DOI: 10.1038/s41380-019-0547-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2018] [Revised: 08/13/2019] [Accepted: 08/19/2019] [Indexed: 12/21/2022]
Abstract
Synaptic plasticity requires a tight control of mRNA levels in dendrites. RNA translation and degradation pathways have been recently linked to neurodevelopmental and neuropsychiatric diseases, suggesting a role for RNA regulation in synaptic plasticity and cognition. While the local translation of specific mRNAs has been implicated in synaptic plasticity, the tightly controlled mechanisms that regulate local quantity of specific mRNAs remain poorly understood. Despite being the only RNA regulatory pathway that is associated with multiple mental illnesses, the nonsense-mediated mRNA decay (NMD) pathway presents an unexplored regulatory mechanism for synaptic function and plasticity. Here, we show that neuron-specific disruption of UPF2, an NMD component, in adulthood attenuates learning, memory, spine density, synaptic plasticity (L-LTP), and potentiates perseverative/repetitive behavior in mice. We report that the NMD pathway operates within dendrites to regulate Glutamate Receptor 1 (GLUR1) surface levels. Specifically, UPF2 modulates the internalization of GLUR1 and promotes its local synthesis in dendrites. We identified neuronal Prkag3 mRNA as a mechanistic substrate for NMD that contributes to the UPF2-mediated regulation of GLUR1 by limiting total GLUR1 levels. These data establish that UPF2 regulates synaptic plasticity, cognition, and local protein synthesis in dendrites, providing fundamental insight into the neuron-specific function of NMD within the brain.
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7
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Hong J, Heo WD. Optogenetic Modulation of TrkB Signaling in the Mouse Brain. J Mol Biol 2020; 432:815-827. [PMID: 31962123 DOI: 10.1016/j.jmb.2020.01.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Revised: 12/22/2019] [Accepted: 01/07/2020] [Indexed: 12/17/2022]
Abstract
Optogenetic activation of receptors has advantages compared with chemical or ligand treatment because of its high spatial and temporal precision. Especially in the brain, the use of a genetically encoded light-tunable receptor is superior to direct infusion or systemic drug treatment. We applied light-activatable TrkB receptors in the mouse brain with reduced basal activity by incorporating Cry2PHR mutant, Opto-cytTrkB(E281A). Upon AAV mediated gene delivery, this form was expressed at sufficient levels in the mouse hippocampus (HPC) and medial entorhinal cortex (MEC) retaining normal canonical signal transduction by the blue light stimulus, even by delivery of noninvasive LED light on the mouse head. Within target cells, where its expression was driven by a cell type-specific promoter, Opto-cytTrkB(E281A)-mediated TrkB signaling could be controlled by adjusting light-stimulating conditions. We further demonstrated that Opto-cytTrkB(E281A) could locally induce TrkB signaling in axon terminals in the MEC-HPC. In summary, Opto-cytTrkB(E281A) will be useful for elucidating time- and region-specific roles of TrkB signaling ranging from cellular function to neural circuit mechanisms.
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Affiliation(s)
- Jongryul Hong
- Department of Biological Science, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 305-701, Republic of Korea
| | - Won Do Heo
- Department of Biological Science, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 305-701, Republic of Korea; Center for Cognition and Sociality, Institute for Basic Science (IBS), Daejeon, 305-701, Republic of Korea; KAIST Institute for the BioCentury, KAIST, Daejeon, 305-701, Republic of Korea.
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8
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Steward O, Coulibaly AP, Metcalfe M, Yonan JM, Yee KM. AAVshRNA-mediated PTEN knockdown in adult neurons attenuates activity-dependent immediate early gene induction. Exp Neurol 2019; 326:113098. [PMID: 31707081 DOI: 10.1016/j.expneurol.2019.113098] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Revised: 10/23/2019] [Accepted: 11/05/2019] [Indexed: 12/22/2022]
Abstract
Genetic deletion or knockdown of PTEN enables regeneration of CNS axons, enhances sprouting of intact axons after injury, and induces de novo growth of uninjured adult neurons. It is unknown, however how PTEN deletion in mature neurons alters neuronal physiology. As a first step to address this question, we used immunocytochemistry for activity-dependent markers to assess consequences of PTEN knockdown in cortical neurons and granule cells of the dentate gyrus. In adult rats that received unilateral intra-cortical injections of AAV expressing shRNA against PTEN, immunostaining for c-fos under resting conditions (home cage, HC) and after 1 h of exploration of a novel enriched environment (EE) revealed no hot spots of c-fos expression that would suggest abnormal activity. Counts revealed similar numbers of c-fos positive neurons in the area of PTEN deletion vs. homologous areas in the contralateral cortex in the HC and similar induction of c-fos with EE. However, IEG induction in response to high frequency stimulation (HFS) of the cortex was attenuated in areas of PTEN deletion. In rats with AAVshRNA-mediated PTEN deletion in the dentate gyrus, induction of the IEGs c-fos and Arc with HFS of the perforant path was abrogated in areas of PTEN deletion. Immunostaining using phosphospecific antibodies for phospho-S6 (a downstream marker for mTOR activation) and phospho-ERK1/2 revealed abrogation of S6 phosphorylation in PTEN-deleted areas but preserved activation of phosphorylation of ERK1/2. SIGNIFICANCE STATEMENT: Deletion or knockdown of the tumor suppressor gene PTEN enables regenerative growth of adult CNS axons after injury, which is accompanied by enhanced recovery of function. Consequently, PTEN represents a potential target for therapeutic interventions to enhance recovery after CNS injury. Here we show that activity-dependent IEG induction is attenuated in PTEN-depleted neurons. These findings raise the intriguing possibility that functional recovery due to regenerative growth may be limited by the disruption of plasticity-related signaling pathways, and that recovery might be enhanced by restoring PTEN expression after regenerative growth has been achieved.
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Affiliation(s)
- Oswald Steward
- Reeve-Irvine Research Center, University of California Irvine, USA; Departments of Anatomy & Neurobiology, University of California Irvine, USA; Departments of Neurobiology & Behavior, University of California Irvine, USA; Department of Neurosurgery, University of California Irvine, USA; School of Medicine, University of California Irvine, USA.
| | - Aminata P Coulibaly
- Reeve-Irvine Research Center, University of California Irvine, USA; Departments of Anatomy & Neurobiology, University of California Irvine, USA; School of Medicine, University of California Irvine, USA
| | - Mariajose Metcalfe
- Reeve-Irvine Research Center, University of California Irvine, USA; Departments of Anatomy & Neurobiology, University of California Irvine, USA; School of Medicine, University of California Irvine, USA
| | - Jennifer M Yonan
- Reeve-Irvine Research Center, University of California Irvine, USA; Departments of Anatomy & Neurobiology, University of California Irvine, USA; School of Medicine, University of California Irvine, USA
| | - Kelly M Yee
- Reeve-Irvine Research Center, University of California Irvine, USA; Departments of Anatomy & Neurobiology, University of California Irvine, USA; School of Medicine, University of California Irvine, USA
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9
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Kim S, Thomasy SM, Raghunathan VK, Teixeira LB, Moshiri A, FitzGerald P, Murphy CJ. Ocular phenotypic consequences of a single copy deletion of the Yap1 gene ( Yap1 +/-) in mice. Mol Vis 2019; 25:129-142. [PMID: 30820148 PMCID: PMC6382475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2018] [Accepted: 02/15/2019] [Indexed: 11/29/2022] Open
Abstract
PURPOSE To identify the effects of a single copy deletion of Yap1 (Yap1 +/-) in the mouse eye, the ocular phenotypic consequences of Yap1 +/- were determined in detail. METHODS Complete ophthalmic examinations, as well as corneal esthesiometry, the phenol red thread test, intraocular pressure, and Fourier-domain optical coherence tomography were performed on Yap1 +/- and age-matched wild-type (WT) mice between eyelid opening (2 weeks after birth) and adulthood (2 months and 1 year after birth). Following euthanasia, enucleated eyes were characterized histologically. RESULTS Microphthalmia with small palpebral fissures, corneal fibrosis, and reduced corneal sensation were common findings in the Yap1 +/- mice. Generalized corneal fibrosis precluded clinical examination of the posterior structures. Histologically, thinning and keratinization of the corneal epithelium were observed in the Yap1 +/- mice in comparison with the WT mice. Distorted collagen fiber arrangement and hypercellularity of keratocytes were observed in the stroma. Descemet's membrane was extremely thin and lacked an endothelial layer in the Yap1 +/- mice. The iris was adherent to the posterior cornea along most of its surface creating a distorted contour. Most of the Yap1 +/- eyes were microphakic with swollen fibers and bladder cells. The retinas of the Yap1 +/- mice were normal at 2 weeks and 2 months of age, but the presence of retinal abnormalities, including retinoschisis and detachment, was markedly increased in the Yap1 +/- mice at 1 year of age. CONCLUSIONS The results show that the heterozygous deletion of the Yap1 gene in mice leads to complex ocular abnormalities, including microphthalmia, corneal fibrosis, anterior segment dysgenesis, and cataract.
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Affiliation(s)
- Soohyun Kim
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California Davis, Davis, CA
| | - Sara M. Thomasy
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California Davis, Davis, CA,Department of Ophthalmology & Vision Science, School of Medicine, School of Medicine, University of California Davis, Davis, CA
| | - Vijay Krishna Raghunathan
- Department of Basic Sciences, College of Optometry, University of Houston, Houston, TX,The Ocular Surface Institute, College of Optometry, University of Houston, Houston, TX,Department of Biomedical Engineering, Cullen College of Engineering, University of Houston, Houston, TX
| | - Leandro B.C. Teixeira
- Comparative Ocular Pathology Laboratory of Wisconsin, Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, WI
| | - Ala Moshiri
- Department of Ophthalmology & Vision Science, School of Medicine, School of Medicine, University of California Davis, Davis, CA
| | - Paul FitzGerald
- Department of Ophthalmology & Vision Science, School of Medicine, School of Medicine, University of California Davis, Davis, CA,Department of Cell Biology and Human Anatomy, School of Medicine, School of Medicine, University of California Davis, Davis, CA
| | - Christopher J. Murphy
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California Davis, Davis, CA,Department of Ophthalmology & Vision Science, School of Medicine, School of Medicine, University of California Davis, Davis, CA
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10
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Andreassi C, Crerar H, Riccio A. Post-transcriptional Processing of mRNA in Neurons: The Vestiges of the RNA World Drive Transcriptome Diversity. Front Mol Neurosci 2018; 11:304. [PMID: 30210293 PMCID: PMC6121099 DOI: 10.3389/fnmol.2018.00304] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Accepted: 08/09/2018] [Indexed: 12/17/2022] Open
Abstract
Neurons are morphologically complex cells that rely on the compartmentalization of protein expression to develop and maintain their extraordinary cytoarchitecture. This formidable task is achieved, at least in part, by targeting mRNA to subcellular compartments where they are rapidly translated. mRNA transcripts are the conveyor of genetic information from DNA to the translational machinery, however, they are also endowed with additional functions linked to both the coding sequence (open reading frame, or ORF) and the flanking 5′ and 3′ untranslated regions (UTRs), that may harbor coding-independent functions. In this review, we will highlight recent evidences supporting new coding-dependent and -independent functions of mRNA and discuss how nuclear and cytoplasmic post-transcriptional modifications of mRNA contribute to localization and translation in mammalian cells with specific emphasis on neurons. We also describe recently developed techniques that can be employed to study RNA dynamics at subcellular level in eukaryotic cells in developing and regenerating neurons.
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Affiliation(s)
- Catia Andreassi
- MRC Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
| | - Hamish Crerar
- MRC Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
| | - Antonella Riccio
- MRC Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
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11
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Wall MJ, Collins DR, Chery SL, Allen ZD, Pastuzyn ED, George AJ, Nikolova VD, Moy SS, Philpot BD, Shepherd JD, Müller J, Ehlers MD, Mabb AM, Corrêa SAL. The Temporal Dynamics of Arc Expression Regulate Cognitive Flexibility. Neuron 2018; 98:1124-1132.e7. [PMID: 29861284 PMCID: PMC6030446 DOI: 10.1016/j.neuron.2018.05.012] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Revised: 04/06/2018] [Accepted: 05/04/2018] [Indexed: 10/29/2022]
Abstract
Neuronal activity regulates the transcription and translation of the immediate-early gene Arc/Arg3.1, a key mediator of synaptic plasticity. Proteasome-dependent degradation of Arc tightly limits its temporal expression, yet the significance of this regulation remains unknown. We disrupted the temporal control of Arc degradation by creating an Arc knockin mouse (ArcKR) where the predominant Arc ubiquitination sites were mutated. ArcKR mice had intact spatial learning but showed specific deficits in selecting an optimal strategy during reversal learning. This cognitive inflexibility was coupled to changes in Arc mRNA and protein expression resulting in a reduced threshold to induce mGluR-LTD and enhanced mGluR-LTD amplitude. These findings show that the abnormal persistence of Arc protein limits the dynamic range of Arc signaling pathways specifically during reversal learning. Our work illuminates how the precise temporal control of activity-dependent molecules, such as Arc, regulates synaptic plasticity and is crucial for cognition.
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Affiliation(s)
- Mark J Wall
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK
| | - Dawn R Collins
- Warwick Medical School, University of Warwick, Coventry, CV4 7AL, UK
| | - Samantha L Chery
- Neuroscience Institute, Georgia State University, Atlanta, GA 30303, USA
| | - Zachary D Allen
- Neuroscience Institute, Georgia State University, Atlanta, GA 30303, USA
| | - Elissa D Pastuzyn
- Department of Neurobiology and Anatomy, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
| | - Arlene J George
- Neuroscience Institute, Georgia State University, Atlanta, GA 30303, USA
| | - Viktoriya D Nikolova
- Department of Psychiatry and the Carolina Institute for Developmental Disorders, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Sheryl S Moy
- Department of Psychiatry and the Carolina Institute for Developmental Disorders, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Benjamin D Philpot
- Neuroscience Center, Department of Cell Biology & Physiology, and the Carolina Institute for Developmental Disorders, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Jason D Shepherd
- Department of Neurobiology and Anatomy, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
| | - Jürgen Müller
- Bradford School of Pharmacy and Medical Sciences, University of Bradford, Bradford, BD7 1DP, UK
| | | | - Angela M Mabb
- Neuroscience Institute, Georgia State University, Atlanta, GA 30303, USA.
| | - Sonia A L Corrêa
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK; Bradford School of Pharmacy and Medical Sciences, University of Bradford, Bradford, BD7 1DP, UK.
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12
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Paolantoni C, Ricciardi S, De Paolis V, Okenwa C, Catalanotto C, Ciotti MT, Cattaneo A, Cogoni C, Giorgi C. Arc 3' UTR Splicing Leads to Dual and Antagonistic Effects in Fine-Tuning Arc Expression Upon BDNF Signaling. Front Mol Neurosci 2018; 11:145. [PMID: 29755318 PMCID: PMC5934489 DOI: 10.3389/fnmol.2018.00145] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Accepted: 04/10/2018] [Indexed: 01/02/2023] Open
Abstract
Activity-regulated cytoskeletal associated protein (Arc) is an immediate-early gene critically involved in synaptic plasticity and memory consolidation. Arc mRNA is rapidly induced by synaptic activation and a portion is locally translated in dendrites where it modulates synaptic strength. Being an activity-dependent effector of homeostatic balance, regulation of Arc is uniquely tuned to result in short-lived bursts of expression. Cis-Acting elements that control its transitory expression post-transcriptionally reside primarily in Arc mRNA 3′ UTR. These include two conserved introns which distinctively modulate Arc mRNA stability by targeting it for destruction via the nonsense mediated decay pathway. Here, we further investigated how splicing of the Arc mRNA 3′ UTR region contributes to modulate Arc expression in cultured neurons. Unexpectedly, upon induction with brain derived neurotrophic factor, translational efficiency of a luciferase reporter construct harboring Arc 3′ UTR is significantly upregulated and this effect is dependent on splicing of Arc introns. We find that, eIF2α dephosphorylation, mTOR, ERK, PKC, and PKA activity are key to this process. Additionally, CREB-dependent transcription is required to couple Arc 3′ UTR-splicing to its translational upregulation, suggesting the involvement of de novo transcribed trans-acting factors. Overall, splicing of Arc 3′ UTR exerts a dual and unique effect in fine-tuning Arc expression upon synaptic signaling: while inducing mRNA decay to limit the time window of Arc expression, it also elicits translation of the decaying mRNA. This antagonistic effect likely contributes to the achievement of a confined yet efficient burst of Arc protein expression, facilitating its role as an effector of synapse-specific plasticity.
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Affiliation(s)
- Chiara Paolantoni
- European Brain Research Institute Rita Levi-Montalcini Rome, Rome, Italy.,Department of Biology and Biotechnology, Sapienza University of Rome, Rome, Italy
| | - Simona Ricciardi
- European Brain Research Institute Rita Levi-Montalcini Rome, Rome, Italy.,Department of Biology and Biotechnology, Sapienza University of Rome, Rome, Italy
| | - Veronica De Paolis
- European Brain Research Institute Rita Levi-Montalcini Rome, Rome, Italy.,Department of Experimental Medicine and Surgery, University of Rome Tor Vergata, Rome, Italy
| | - Chinenye Okenwa
- European Brain Research Institute Rita Levi-Montalcini Rome, Rome, Italy
| | - Caterina Catalanotto
- Department of Cellular Biotechnologies and Hematology, Sapienza University of Rome, Rome, Italy
| | - Maria T Ciotti
- Institute of Cell Biology and Neurobiology, National Research Council, Rome, Italy
| | - Antonino Cattaneo
- European Brain Research Institute Rita Levi-Montalcini Rome, Rome, Italy.,Bio@SNS Laboratory, Scuola Normale Superiore, Pisa, Italy
| | - Carlo Cogoni
- Department of Cellular Biotechnologies and Hematology, Sapienza University of Rome, Rome, Italy
| | - Corinna Giorgi
- European Brain Research Institute Rita Levi-Montalcini Rome, Rome, Italy
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