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Di Liegro CM, Schiera G, Schirò G, Di Liegro I. Role of Post-Transcriptional Regulation in Learning and Memory in Mammals. Genes (Basel) 2024; 15:337. [PMID: 38540396 PMCID: PMC10970538 DOI: 10.3390/genes15030337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Revised: 02/27/2024] [Accepted: 03/01/2024] [Indexed: 06/14/2024] Open
Abstract
After many decades, during which most molecular studies on the regulation of gene expression focused on transcriptional events, it was realized that post-transcriptional control was equally important in order to determine where and when specific proteins were to be synthesized. Translational regulation is of the most importance in the brain, where all the steps of mRNA maturation, transport to different regions of the cells and actual expression, in response to specific signals, constitute the molecular basis for neuronal plasticity and, as a consequence, for structural stabilization/modification of synapses; notably, these latter events are fundamental for the highest brain functions, such as learning and memory, and are characterized by long-term potentiation (LTP) of specific synapses. Here, we will discuss the molecular bases of these fundamental events by considering both the role of RNA-binding proteins (RBPs) and the effects of non-coding RNAs involved in controlling splicing, editing, stability and translation of mRNAs. Importantly, it has also been found that dysregulation of mRNA metabolism/localization is involved in many pathological conditions, arising either during brain development or in the adult nervous system.
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Affiliation(s)
- Carlo Maria Di Liegro
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies, University of Palermo, 90128 Palermo, Italy; (C.M.D.L.); (G.S.)
| | - Gabriella Schiera
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies, University of Palermo, 90128 Palermo, Italy; (C.M.D.L.); (G.S.)
| | - Giuseppe Schirò
- Department of Biomedicine, Neurosciences and Advanced Diagnostics, University of Palermo, 90127 Palermo, Italy;
- Neurology and Multiple Sclerosis Center, Unità Operativa Complessa (UOC), Foundation Institute “G. Giglio”, 90015 Cefalù, Italy
| | - Italia Di Liegro
- Department of Biomedicine, Neurosciences and Advanced Diagnostics, University of Palermo, 90127 Palermo, Italy;
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2
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Kurosaki T, Rambout X, Maquat LE. FMRP-mediated spatial regulation of physiologic NMD targets in neuronal cells. Genome Biol 2024; 25:31. [PMID: 38263082 PMCID: PMC10804635 DOI: 10.1186/s13059-023-03146-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Accepted: 12/14/2023] [Indexed: 01/25/2024] Open
Abstract
In non-polarized cells, nonsense-mediated mRNA decay (NMD) generally begins during the translation of newly synthesized mRNAs after the mRNAs are exported to the cytoplasm. Binding of the FMRP translational repressor to UPF1 on NMD targets mainly inhibits NMD. However, in polarized cells like neurons, FMRP additionally localizes mRNAs to cellular projections. Here, we review the literature and evaluate available transcriptomic data to conclude that, in neurons, the translation of physiologic NMD targets bound by FMRP is partially inhibited until the mRNAs localize to projections. There, FMRP displacement in response to signaling induces a burst in protein synthesis followed by rapid mRNA decay.
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Affiliation(s)
- Tatsuaki Kurosaki
- Department of Biochemistry and Biophysics, School of Medicine and Dentistry, University of Rochester, Rochester, NY, 14642, USA
- Center for RNA Biology, University of Rochester, Rochester, NY, 14642, USA
| | - Xavier Rambout
- Department of Biochemistry and Biophysics, School of Medicine and Dentistry, University of Rochester, Rochester, NY, 14642, USA
- Center for RNA Biology, University of Rochester, Rochester, NY, 14642, USA
| | - Lynne E Maquat
- Department of Biochemistry and Biophysics, School of Medicine and Dentistry, University of Rochester, Rochester, NY, 14642, USA.
- Center for RNA Biology, University of Rochester, Rochester, NY, 14642, USA.
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3
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Niu M, Cao W, Wang Y, Zhu Q, Luo J, Wang B, Zheng H, Weitz DA, Zong C. Droplet-based transcriptome profiling of individual synapses. Nat Biotechnol 2023; 41:1332-1344. [PMID: 36646931 DOI: 10.1038/s41587-022-01635-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Accepted: 12/06/2022] [Indexed: 01/17/2023]
Abstract
Synapses are crucial structures that mediate signal transmission between neurons in complex neural circuits and display considerable morphological and electrophysiological heterogeneity. So far we still lack a high-throughput method to profile the molecular heterogeneity among individual synapses. In the present study, we develop a droplet-based single-cell (sc) total-RNA-sequencing platform, called Multiple-Annealing-and-Tailing-based Quantitative scRNA-seq in Droplets, for transcriptome profiling of individual neurites, primarily composed of synaptosomes. In the synaptosome transcriptome, or 'synaptome', profiling of both mouse and human brain samples, we detect subclusters among synaptosomes that are associated with neuronal subtypes and characterize the landscape of transcript splicing that occurs within synapses. We extend synaptome profiling to synaptopathy in an Alzheimer's disease (AD) mouse model and discover AD-associated synaptic gene expression changes that cannot be detected by single-nucleus transcriptome profiling. Overall, our results show that this platform provides a high-throughput, single-synaptosome transcriptome profiling tool that will facilitate future discoveries in neuroscience.
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Affiliation(s)
- Muchun Niu
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
- Integrative Molecular and Biomedical Sciences Graduate Program, Baylor College of Medicine, Houston, TX, USA
| | - Wenjian Cao
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
- Genetics and Genomics Graduate Program, Baylor College of Medicine, Houston, TX, USA
- Research Center for Analytical Instrumentation, Institute of Cyber-Systems and Control, State Key Laboratory of Industrial Control Technology, Zhejiang University, Hangzhou, China
| | - Yongcheng Wang
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
- Wyss Institute of Bioinspired Engineering, Harvard University, Cambridge, MA, USA
- Liangzhu Laboratory, Zhejiang University Medical Center, Hangzhou, China
| | - Qiangyuan Zhu
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
- Research Center for Analytical Instrumentation, Institute of Cyber-Systems and Control, State Key Laboratory of Industrial Control Technology, Zhejiang University, Hangzhou, China
| | - Jiayi Luo
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
- Cancer and Cell Biology Graduate Program, Baylor College of Medicine, Houston, TX, USA
| | - Baiping Wang
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
- Huffington Center on Aging, Baylor College of Medicine, Houston, TX, USA
| | - Hui Zheng
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
- Huffington Center on Aging, Baylor College of Medicine, Houston, TX, USA
| | - David A Weitz
- Wyss Institute of Bioinspired Engineering, Harvard University, Cambridge, MA, USA.
- Department of Physics and School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA.
| | - Chenghang Zong
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA.
- Dan L. Duncan Comprehensive Cancer Center, Baylor College of Medicine, Houston, TX, USA.
- McNair Medical Institute, Baylor College of Medicine, Houston, TX, USA.
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4
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Busselez J, Uzbekov RE, Franco B, Pancione M. New insights into the centrosome-associated spliceosome components as regulators of ciliogenesis and tissue identity. WILEY INTERDISCIPLINARY REVIEWS. RNA 2023; 14:e1776. [PMID: 36717357 DOI: 10.1002/wrna.1776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Revised: 12/20/2022] [Accepted: 12/27/2022] [Indexed: 02/01/2023]
Abstract
Biomolecular condensates are membrane-less assemblies of proteins and nucleic acids. Centrosomes are biomolecular condensates that play a crucial role in nuclear division, cytoskeletal remodeling, and cilia formation in animal cells. Spatial omics technology is providing new insights into the dynamic exchange of spliceosome components between the nucleus and the centrosome/cilium. Intriguingly, centrosomes are emerging as cytoplasmic sites for information storage, enriched with RNA molecules and RNA-processing proteins. Furthermore, growing evidence supports the view that nuclear spliceosome components assembled at the centrosome function as potential coordinators of splicing subprograms, pluripotency, and cell differentiation. In this article, we first discuss the current understanding of the centrosome/cilium complex, which controls both stem cell differentiation and pluripotency. We next explore the molecular mechanisms that govern splicing factor assembly and disassembly around the centrosome and examine how RNA processing pathways contribute to ciliogenesis. Finally, we discuss numerous unresolved compelling questions regarding the centrosome-associated spliceosome components and transcript variants within the cytoplasm as sources of RNA-based secondary messages in the regulation of cell identity and cell fate determination. This article is categorized under: RNA-Based Catalysis > RNA Catalysis in Splicing and Translation RNA Interactions with Proteins and Other Molecules > RNA-Protein Complexes RNA Processing > Splicing Regulation/Alternative Splicing RNA Processing > RNA Processing.
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Affiliation(s)
- Johan Busselez
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch-Graffenstaden, France
| | - Rustem E Uzbekov
- Faculté de Médecine, Université de Tours, Tours, France
- Faculty of Bioengineering and Bioinformatics, Moscow State University, Moscow, Russia
| | - Brunella Franco
- Telethon Institute of Genetics and Medicine (TIGEM), Naples, Italy
- Department of Translational Medicine, Medical Genetics, University of Naples "Federico II", Naples, Italy
- Scuola Superiore Meridionale (SSM, School of Advanced Studies), Genomics and Experimental Medicine program, University of Naples Federico II, Naples, Italy
| | - Massimo Pancione
- Department of Sciences and Technologies, University of Sannio, Benevento, Italy
- Department of Biochemistry and Molecular Biology, Faculty of Pharmacy, Complutense University Madrid, Madrid, Spain
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5
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Borg R, Herrera P, Purkiss A, Cacciottolo R, Cauchi RJ. Reduced levels of ALS gene DCTN1 induce motor defects in Drosophila. Front Neurosci 2023; 17:1164251. [PMID: 37360176 PMCID: PMC10289029 DOI: 10.3389/fnins.2023.1164251] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2023] [Accepted: 05/16/2023] [Indexed: 06/28/2023] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a rapidly progressive neuromuscular disease that has a strong genetic component. Deleterious variants in the DCTN1 gene are known to be a cause of ALS in diverse populations. DCTN1 encodes the p150 subunit of the molecular motor dynactin which is a key player in the bidirectional transport of cargos within cells. Whether DCTN1 mutations lead to the disease through either a gain or loss of function mechanism remains unresolved. Moreover, the contribution of non-neuronal cell types, especially muscle tissue, to ALS phenotypes in DCTN1 carriers is unknown. Here we show that gene silencing of Dctn1, the Drosophila main orthologue of DCTN1, either in neurons or muscles is sufficient to cause climbing and flight defects in adult flies. We also identify Dred, a protein with high homology to Drosophila Dctn1 and human DCTN1, that on loss of function also leads to motoric impairments. A global reduction of Dctn1 induced a significant reduction in the mobility of larvae and neuromuscular junction (NMJ) deficits prior to death at the pupal stage. RNA-seq and transcriptome profiling revealed splicing alterations in genes required for synapse organisation and function, which may explain the observed motor dysfunction and synaptic defects downstream of Dctn1 ablation. Our findings support the possibility that loss of DCTN1 function can lead to ALS and underscore an important requirement for DCTN1 in muscle in addition to neurons.
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Affiliation(s)
- Rebecca Borg
- Centre for Molecular Medicine and Biobanking, Biomedical Sciences Building, University of Malta, Msida, Malta
- Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida, Malta
| | - Paul Herrera
- Centre for Molecular Medicine and Biobanking, Biomedical Sciences Building, University of Malta, Msida, Malta
- Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida, Malta
| | - Angie Purkiss
- Centre for Molecular Medicine and Biobanking, Biomedical Sciences Building, University of Malta, Msida, Malta
- Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida, Malta
| | - Rebecca Cacciottolo
- Centre for Molecular Medicine and Biobanking, Biomedical Sciences Building, University of Malta, Msida, Malta
- Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida, Malta
| | - Ruben J. Cauchi
- Centre for Molecular Medicine and Biobanking, Biomedical Sciences Building, University of Malta, Msida, Malta
- Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida, Malta
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6
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CPEB3 low-complexity motif regulates local protein synthesis via protein-protein interactions in neuronal ribonucleoprotein granules. Proc Natl Acad Sci U S A 2023; 120:e2114747120. [PMID: 36716374 PMCID: PMC9964033 DOI: 10.1073/pnas.2114747120] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Biomolecular condensates, membraneless organelles found throughout the cell, play critical roles in many aspects of cellular function. Ribonucleoprotein granules (RNPs) are a type of biomolecular condensate necessary for local protein synthesis and are involved in synaptic plasticity and long-term memory. Most of the proteins in RNPs possess low-complexity motifs (LCM), allowing for increased promiscuity of protein-protein interactions. Here, we describe the importance of protein-protein interactions mediated by the LCM of RNA-binding protein cytoplasmic polyadenylation element binding protein 3 (CPEB3). CPEB3 is necessary for long-term synaptic plasticity and memory persistence, but the mechanisms involved are still not completely elucidated. We now present key mechanisms involved in its regulation of synaptic plasticity. We find that CPEB3-LCM plays a role in appropriate local protein synthesis of messenger ribonucleic acid (mRNA) targets, through crucial protein-protein interactions that drive localization to neuronal Decapping protein 1 (DCP1)-bodies. Translation-promoting CPEB3 and translation-inhibiting CPEB1 are packaged into neuronal RNP granules immediately after chemical long-term potentiation is induced, but only translation-promoting CPEB3 is repackaged to these organelles at later time points. This localization to neuronal RNP granules is critical for functional influence on translation as well as overall local protein synthesis (measured as α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) insertion into the membrane and localization to the synapse). We therefore conclude that protein-protein interaction between the LCM of CPEB3 plays a critical role in local protein synthesis by utilizing neuronal RNP granules.
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7
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Nikolaou N, Gordon PM, Hamid F, Taylor R, Lloyd-Jones J, Makeyev EV, Houart C. Cytoplasmic pool of U1 spliceosome protein SNRNP70 shapes the axonal transcriptome and regulates motor connectivity. Curr Biol 2022; 32:5099-5115.e8. [PMID: 36384140 DOI: 10.1016/j.cub.2022.10.048] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 09/09/2022] [Accepted: 10/21/2022] [Indexed: 11/17/2022]
Abstract
Regulation of pre-mRNA splicing and polyadenylation plays a profound role in neurons by diversifying the proteome and modulating gene expression in response to physiological cues. Although most of the pre-mRNA processing is thought to occur in the nucleus, numerous splicing regulators are also found in neurites. Here, we show that U1-70K/SNRNP70, a component of the major spliceosome, localizes in RNA-associated granules in zebrafish axons. We identify the extra-nuclear SNRNP70 as an important regulator of motor axonal growth, nerve-dependent acetylcholine receptor (AChR) clustering, and neuromuscular synaptogenesis. This cytoplasmic pool has a protective role for a limited number of transcripts regulating their abundance and trafficking inside axons. Moreover, non-nuclear SNRNP70 regulates splice variants of transcripts such as agrin, thereby controlling synapse formation. Our results point to an unexpected, yet essential, function of non-nuclear SNRNP70 in axonal development, indicating a role of spliceosome proteins in cytoplasmic RNA metabolism during neuronal connectivity.
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Affiliation(s)
- Nikolas Nikolaou
- Centre for Developmental Neurobiology MRC CNDD, IoPPN, Guy's Campus, King's College London, London SE1 1UL, UK; Department of Life Sciences, University of Bath, Bath BA2 7AY, UK.
| | - Patricia M Gordon
- Centre for Developmental Neurobiology MRC CNDD, IoPPN, Guy's Campus, King's College London, London SE1 1UL, UK
| | - Fursham Hamid
- Centre for Developmental Neurobiology MRC CNDD, IoPPN, Guy's Campus, King's College London, London SE1 1UL, UK
| | - Richard Taylor
- Centre for Developmental Neurobiology MRC CNDD, IoPPN, Guy's Campus, King's College London, London SE1 1UL, UK
| | | | - Eugene V Makeyev
- Centre for Developmental Neurobiology MRC CNDD, IoPPN, Guy's Campus, King's College London, London SE1 1UL, UK
| | - Corinne Houart
- Centre for Developmental Neurobiology MRC CNDD, IoPPN, Guy's Campus, King's College London, London SE1 1UL, UK.
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8
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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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9
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Nagel M, Noss M, Xu J, Horn N, Ueffing M, Boldt K, Schuele R. The kinesin motor KIF1C is a putative transporter of the exon junction complex in neuronal cells. RNA (NEW YORK, N.Y.) 2022; 29:rna.079426.122. [PMID: 36316088 PMCID: PMC9808568 DOI: 10.1261/rna.079426.122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Accepted: 10/18/2022] [Indexed: 06/16/2023]
Abstract
Neurons critically depend on regulated RNA localization and tight control of spatio-temporal gene expression to maintain their morphological and functional integrity. Mutations in the kinesin motor protein gene KIF1C cause Hereditary Spastic Paraplegia, an autosomal recessive disease leading to predominant degeneration of the long axons of central motoneurons. In this study we aimed to gain insight into the molecular function of KIF1C and understand how KIF1C dysfunction contributes to motoneuron degeneration. We used affinity proteomics in neuronally differentiated neuroblastoma cells (SH-SY5Y) to identify the protein complex associated with KIF1C in neuronal cells; candidate interactions were then validated by immunoprecipitation and mislocalization of putative KIF1C cargoes was studied by immunostainings. We found KIF1C to interact with all core components of the exon junction complex (EJC); expression of mutant KIF1C in neuronal cells leads to loss of the typical localization distally in neurites. Instead, EJC core components accumulate in the pericentrosomal region, here co-localizing with mutant KIF1C. These findings suggest KIF1C as a neuronal transporter of the EJC. Interestingly, the binding of KIF1C to the EJC is RNA-mediated, as treatment with RNAse prior to immunoprecipitation almost completely abolishes the interaction. Silica-based solid-phase extraction of UV-crosslinked RNA-protein complexes furthermore supports direct interaction of KIF1C with RNA, as recently also demonstrated for kinesin heavy chain. Taken together, our findings are consistent with a model where KIF1C transports mRNA in an EJC-bound and therefore transcriptionally silenced state along neurites, thus providing the missing link between the EJC and mRNA localization in neurons.
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Affiliation(s)
- Maike Nagel
- German Center for Neurodegenerative Diseases, Tuebingen; Department of Neurodegenerative Diseases, Hertie-Institute for Clinical Brain Research and Center of Neurology, University of Tuebingen; Graduate School of Cellular and Molecular Neuroscience
| | - Marvin Noss
- Department of Neurodegenerative Diseases, Hertie-Institute for Clinical Brain Research and Center of Neurology, University of Tuebingen
| | - Jishu Xu
- Department of Neurodegenerative Diseases, Hertie-Institute for Clinical Brain Research and Center of Neurology, University of Tuebingen; Institute of Medical Genetics and Applied Genomics, University of Tuebingen; Graduate School
| | - Nicola Horn
- Institute for Ophthalmic Research, University of Tuebingen
| | - Marius Ueffing
- Institute of Ophthalmic Research, University of Tuebingen
| | - Karsten Boldt
- Institute of Ophthalmic Research, University of Tuebingen
| | - Rebecca Schuele
- Department of Neurodegenerative Diseases, Hertie-Institute for Clinical Brain Research and Center of Neurology, University of Tuebingen; German Center for Neurodegenerative Diseases, Tuebingen
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10
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Laszlo ZI, Hindley N, Sanchez Avila A, Kline RA, Eaton SL, Lamont DJ, Smith C, Spires-Jones TL, Wishart TM, Henstridge CM. Synaptic proteomics reveal distinct molecular signatures of cognitive change and C9ORF72 repeat expansion in the human ALS cortex. Acta Neuropathol Commun 2022; 10:156. [DOI: 10.1186/s40478-022-01455-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Accepted: 09/30/2022] [Indexed: 11/10/2022] Open
Abstract
AbstractIncreasing evidence suggests synaptic dysfunction is a central and possibly triggering factor in Amyotrophic Lateral Sclerosis (ALS). Despite this, we still know very little about the molecular profile of an ALS synapse. To address this gap, we designed a synaptic proteomics experiment to perform an unbiased assessment of the synaptic proteome in the ALS brain. We isolated synaptoneurosomes from fresh-frozen post-mortem human cortex (11 controls and 18 ALS) and stratified the ALS group based on cognitive profile (Edinburgh Cognitive and Behavioural ALS Screen (ECAS score)) and presence of a C9ORF72 hexanucleotide repeat expansion (C9ORF72-RE). This allowed us to assess regional differences and the impact of phenotype and genotype on the synaptic proteome, using Tandem Mass Tagging-based proteomics. We identified over 6000 proteins in our synaptoneurosomes and using robust bioinformatics analysis we validated the strong enrichment of synapses. We found more than 30 ALS-associated proteins in synaptoneurosomes, including TDP-43, FUS, SOD1 and C9ORF72. We identified almost 500 proteins with altered expression levels in ALS, with region-specific changes highlighting proteins and pathways with intriguing links to neurophysiology and pathology. Stratifying the ALS cohort by cognitive status revealed almost 150 specific alterations in cognitively impaired ALS synaptic preparations. Stratifying by C9ORF72-RE status revealed 330 protein alterations in the C9ORF72-RE +ve group, with KEGG pathway analysis highlighting strong enrichment for postsynaptic dysfunction, related to glutamatergic receptor signalling. We have validated some of these changes by western blot and at a single synapse level using array tomography imaging. In summary, we have generated the first unbiased map of the human ALS synaptic proteome, revealing novel insight into this key compartment in ALS pathophysiology and highlighting the influence of cognitive decline and C9ORF72-RE on synaptic composition.
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11
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Alon S, Goodwin DR, Sinha A, Wassie AT, Chen F, Daugharthy ER, Bando Y, Kajita A, Xue AG, Marrett K, Prior R, Cui Y, Payne AC, Yao CC, Suk HJ, Wang R, Yu CCJ, Tillberg P, Reginato P, Pak N, Liu S, Punthambaker S, Iyer EPR, Kohman RE, Miller JA, Lein ES, Lako A, Cullen N, Rodig S, Helvie K, Abravanel DL, Wagle N, Johnson BE, Klughammer J, Slyper M, Waldman J, Jané-Valbuena J, Rozenblatt-Rosen O, Regev A, Church GM, Marblestone AH, Boyden ES. Expansion sequencing: Spatially precise in situ transcriptomics in intact biological systems. Science 2021; 371:eaax2656. [PMID: 33509999 PMCID: PMC7900882 DOI: 10.1126/science.aax2656] [Citation(s) in RCA: 193] [Impact Index Per Article: 64.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Revised: 05/13/2020] [Accepted: 11/20/2020] [Indexed: 12/12/2022]
Abstract
Methods for highly multiplexed RNA imaging are limited in spatial resolution and thus in their ability to localize transcripts to nanoscale and subcellular compartments. We adapt expansion microscopy, which physically expands biological specimens, for long-read untargeted and targeted in situ RNA sequencing. We applied untargeted expansion sequencing (ExSeq) to the mouse brain, which yielded the readout of thousands of genes, including splice variants. Targeted ExSeq yielded nanoscale-resolution maps of RNAs throughout dendrites and spines in the neurons of the mouse hippocampus, revealing patterns across multiple cell types, layer-specific cell types across the mouse visual cortex, and the organization and position-dependent states of tumor and immune cells in a human metastatic breast cancer biopsy. Thus, ExSeq enables highly multiplexed mapping of RNAs from nanoscale to system scale.
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Affiliation(s)
- Shahar Alon
- Department of Media Arts and Sciences, MIT, Cambridge, MA, USA
- McGovern Institute, MIT, Cambridge, MA, USA
- Faculty of Engineering, Gonda Brain Research Center and Institute of Nanotechnology, Bar-Ilan University, Ramat Gan, Israel
| | - Daniel R Goodwin
- Department of Media Arts and Sciences, MIT, Cambridge, MA, USA
- McGovern Institute, MIT, Cambridge, MA, USA
| | - Anubhav Sinha
- Department of Media Arts and Sciences, MIT, Cambridge, MA, USA
- McGovern Institute, MIT, Cambridge, MA, USA
- Harvard-MIT Program in Health Sciences and Technology, MIT, Cambridge, MA, USA
| | - Asmamaw T Wassie
- Department of Media Arts and Sciences, MIT, Cambridge, MA, USA
- McGovern Institute, MIT, Cambridge, MA, USA
- Department of Biological Engineering, MIT, Cambridge, MA, USA
| | - Fei Chen
- Department of Media Arts and Sciences, MIT, Cambridge, MA, USA
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Evan R Daugharthy
- Department of Genetics, Harvard Medical School, Boston, MA, USA
- Wyss Institute for Biologically Inspired Engineering, Boston, MA, USA
| | - Yosuke Bando
- Department of Media Arts and Sciences, MIT, Cambridge, MA, USA
- Kioxia Corporation, Minato-ku, Tokyo, Japan
| | | | - Andrew G Xue
- Department of Media Arts and Sciences, MIT, Cambridge, MA, USA
| | | | | | - Yi Cui
- Department of Media Arts and Sciences, MIT, Cambridge, MA, USA
- McGovern Institute, MIT, Cambridge, MA, USA
| | - Andrew C Payne
- Department of Media Arts and Sciences, MIT, Cambridge, MA, USA
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Chun-Chen Yao
- Department of Media Arts and Sciences, MIT, Cambridge, MA, USA
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Ho-Jun Suk
- Department of Media Arts and Sciences, MIT, Cambridge, MA, USA
- McGovern Institute, MIT, Cambridge, MA, USA
- Harvard-MIT Program in Health Sciences and Technology, MIT, Cambridge, MA, USA
| | - Ru Wang
- Department of Media Arts and Sciences, MIT, Cambridge, MA, USA
- McGovern Institute, MIT, Cambridge, MA, USA
| | - Chih-Chieh Jay Yu
- Department of Media Arts and Sciences, MIT, Cambridge, MA, USA
- McGovern Institute, MIT, Cambridge, MA, USA
- Department of Biological Engineering, MIT, Cambridge, MA, USA
| | - Paul Tillberg
- Department of Media Arts and Sciences, MIT, Cambridge, MA, USA
| | - Paul Reginato
- Department of Media Arts and Sciences, MIT, Cambridge, MA, USA
- Department of Biological Engineering, MIT, Cambridge, MA, USA
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Genetics, Harvard Medical School, Boston, MA, USA
- Wyss Institute for Biologically Inspired Engineering, Boston, MA, USA
| | - Nikita Pak
- Department of Media Arts and Sciences, MIT, Cambridge, MA, USA
- McGovern Institute, MIT, Cambridge, MA, USA
- Department of Mechanical Engineering, MIT, Cambridge, MA, USA
| | - Songlei Liu
- Department of Genetics, Harvard Medical School, Boston, MA, USA
- Wyss Institute for Biologically Inspired Engineering, Boston, MA, USA
| | - Sukanya Punthambaker
- Department of Genetics, Harvard Medical School, Boston, MA, USA
- Wyss Institute for Biologically Inspired Engineering, Boston, MA, USA
| | - Eswar P R Iyer
- Wyss Institute for Biologically Inspired Engineering, Boston, MA, USA
| | - Richie E Kohman
- Department of Genetics, Harvard Medical School, Boston, MA, USA
- Wyss Institute for Biologically Inspired Engineering, Boston, MA, USA
| | | | - Ed S Lein
- Allen Institute for Brain Science, Seattle, WA, USA
| | - Ana Lako
- Center for Immuno-Oncology (CIO), Dana-Farber Cancer Institute, Boston, MA, USA
| | - Nicole Cullen
- Center for Immuno-Oncology (CIO), Dana-Farber Cancer Institute, Boston, MA, USA
| | - Scott Rodig
- Center for Immuno-Oncology (CIO), Dana-Farber Cancer Institute, Boston, MA, USA
| | - Karla Helvie
- Center for Cancer Genomics, Dana-Farber Cancer Institute, Boston, MA, USA
| | - Daniel L Abravanel
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, USA
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA
| | - Nikhil Wagle
- Center for Cancer Genomics, Dana-Farber Cancer Institute, Boston, MA, USA
| | - Bruce E Johnson
- Center for Cancer Genomics, Dana-Farber Cancer Institute, Boston, MA, USA
| | | | - Michal Slyper
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Julia Waldman
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | | | | | - Aviv Regev
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Koch Institute for Integrative Cancer Research, Department of Biology, MIT, Cambridge, MA, USA
- Howard Hughes Medical Institute, Chevy Chase, MD, USA
| | - George M Church
- Department of Genetics, Harvard Medical School, Boston, MA, USA.
- Wyss Institute for Biologically Inspired Engineering, Boston, MA, USA
| | | | - Edward S Boyden
- Department of Media Arts and Sciences, MIT, Cambridge, MA, USA.
- McGovern Institute, MIT, Cambridge, MA, USA
- Department of Biological Engineering, MIT, Cambridge, MA, USA
- Koch Institute for Integrative Cancer Research, Department of Biology, MIT, Cambridge, MA, USA
- Howard Hughes Medical Institute, Chevy Chase, MD, USA
- Department of Brain and Cognitive Sciences, MIT, Cambridge, MA, USA
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12
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Wang H, Liu L, Rao X, Zeng B, Yu Y, Zhou C, Zeng L, Zheng P, Pu J, Xu S, Cheng K, Zhang H, Ji P, Wei H, Xie P. Integrated phosphoproteomic and metabolomic profiling reveals perturbed pathways in the hippocampus of gut microbiota dysbiosis mice. Transl Psychiatry 2020; 10:346. [PMID: 33051451 PMCID: PMC7553953 DOI: 10.1038/s41398-020-01024-9] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/12/2019] [Revised: 08/27/2020] [Accepted: 09/22/2020] [Indexed: 12/12/2022] Open
Abstract
The dysbiosis of gut microbiota is an important environmental factor that can induce mental disorders, such as depression, through the microbiota-gut-brain axis. However, the underlying pathogenic mechanisms are complex and not completely understood. Here we utilized mass spectrometry to identify the global phosphorylation dynamics in hippocampus tissue in germ-free mice and specific pathogen-free mice (GF vs SPF), fecal microbiota transplantation (FMT) model ("depression microbiota" and the "healthy microbiota" recipient mice). As a result, 327 phosphosites of 237 proteins in GF vs SPF, and 478 phosphosites of 334 proteins in "depression microbiota" vs "healthy microbiota" recipient mice were identified as significant. These phosphorylation dysregulations were consistently associated with glutamatergic neurotransmitter system disturbances. The FMT mice exhibited disturbances in lipid metabolism and amino acid metabolism in both the periphery and brain through integrating phosphoproteomic and metabolomic analysis. Moreover, CAMKII-CREB signaling pathway, in response to these disturbances, was the primary common perturbed cellular process. In addition, we demonstrated that the spliceosome, never directly implicated in mental disorders previously, was a substantially neuronal function disrupted by gut microbiota dysbiosis, and the NCBP1 phosphorylation was identified as a novel pathogenic target. These results present a new perspective to study the pathologic mechanisms of gut microbiota dysbiosis related depression and highlight potential gut-mediated therapies for depression.
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Affiliation(s)
- Haiyang Wang
- grid.459985.cChongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Stomatological Hospital of Chongqing Medical University, 401147 Chongqing, China ,grid.203458.80000 0000 8653 0555College of Biomedical Engineering, Chongqing Medical University, 400016 Chongqing, China ,grid.452206.7NHC Key Laboratory of Diagnosis and Treatment on Brain Functional Diseases, The First Affiliated Hospital of Chongqing Medical University, 400016 Chongqing, China
| | - Lanxiang Liu
- grid.452206.7NHC Key Laboratory of Diagnosis and Treatment on Brain Functional Diseases, The First Affiliated Hospital of Chongqing Medical University, 400016 Chongqing, China ,grid.203458.80000 0000 8653 0555Department of Neurology, Yongchuan Hospital of Chongqing Medical University, 402460 Chongqing, China
| | - Xuechen Rao
- grid.203458.80000 0000 8653 0555College of Biomedical Engineering, Chongqing Medical University, 400016 Chongqing, China ,grid.452206.7NHC Key Laboratory of Diagnosis and Treatment on Brain Functional Diseases, The First Affiliated Hospital of Chongqing Medical University, 400016 Chongqing, China
| | - Benhua Zeng
- grid.410570.70000 0004 1760 6682Department of Laboratory Animal Science, College of Basic Medical Sciences, Third Military Medical University, 400038 Chongqing, China
| | - Ying Yu
- grid.452206.7NHC Key Laboratory of Diagnosis and Treatment on Brain Functional Diseases, The First Affiliated Hospital of Chongqing Medical University, 400016 Chongqing, China
| | - Chanjuan Zhou
- grid.452206.7NHC Key Laboratory of Diagnosis and Treatment on Brain Functional Diseases, The First Affiliated Hospital of Chongqing Medical University, 400016 Chongqing, China
| | - Li Zeng
- grid.452206.7NHC Key Laboratory of Diagnosis and Treatment on Brain Functional Diseases, The First Affiliated Hospital of Chongqing Medical University, 400016 Chongqing, China ,grid.412461.4Department of Nephrology, The Second Affiliated Hospital of Chongqing Medical University, 400010 Chongqing, China
| | - Peng Zheng
- grid.452206.7NHC Key Laboratory of Diagnosis and Treatment on Brain Functional Diseases, The First Affiliated Hospital of Chongqing Medical University, 400016 Chongqing, China ,grid.452206.7Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, 400016 Chongqing, China
| | - Juncai Pu
- grid.452206.7NHC Key Laboratory of Diagnosis and Treatment on Brain Functional Diseases, The First Affiliated Hospital of Chongqing Medical University, 400016 Chongqing, China ,grid.452206.7Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, 400016 Chongqing, China
| | - Shaohua Xu
- grid.452206.7NHC Key Laboratory of Diagnosis and Treatment on Brain Functional Diseases, The First Affiliated Hospital of Chongqing Medical University, 400016 Chongqing, China
| | - Ke Cheng
- grid.452206.7NHC Key Laboratory of Diagnosis and Treatment on Brain Functional Diseases, The First Affiliated Hospital of Chongqing Medical University, 400016 Chongqing, China ,grid.452206.7Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, 400016 Chongqing, China
| | - Hanping Zhang
- grid.452206.7NHC Key Laboratory of Diagnosis and Treatment on Brain Functional Diseases, The First Affiliated Hospital of Chongqing Medical University, 400016 Chongqing, China ,grid.452206.7Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, 400016 Chongqing, China
| | - Ping Ji
- grid.459985.cChongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Stomatological Hospital of Chongqing Medical University, 401147 Chongqing, China
| | - Hong Wei
- Department of Laboratory Animal Science, College of Basic Medical Sciences, Third Military Medical University, 400038, Chongqing, China.
| | - Peng Xie
- Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Stomatological Hospital of Chongqing Medical University, 401147, Chongqing, China. .,NHC Key Laboratory of Diagnosis and Treatment on Brain Functional Diseases, The First Affiliated Hospital of Chongqing Medical University, 400016, Chongqing, China. .,Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, 400016, Chongqing, China.
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13
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Schieweck R, Ninkovic J, Kiebler MA. RNA-binding proteins balance brain function in health and disease. Physiol Rev 2020; 101:1309-1370. [PMID: 33000986 DOI: 10.1152/physrev.00047.2019] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Posttranscriptional gene expression including splicing, RNA transport, translation, and RNA decay provides an important regulatory layer in many if not all molecular pathways. Research in the last decades has positioned RNA-binding proteins (RBPs) right in the center of posttranscriptional gene regulation. Here, we propose interdependent networks of RBPs to regulate complex pathways within the central nervous system (CNS). These are involved in multiple aspects of neuronal development and functioning, including higher cognition. Therefore, it is not sufficient to unravel the individual contribution of a single RBP and its consequences but rather to study and understand the tight interplay between different RBPs. In this review, we summarize recent findings in the field of RBP biology and discuss the complex interplay between different RBPs. Second, we emphasize the underlying dynamics within an RBP network and how this might regulate key processes such as neurogenesis, synaptic transmission, and synaptic plasticity. Importantly, we envision that dysfunction of specific RBPs could lead to perturbation within the RBP network. This would have direct and indirect (compensatory) effects in mRNA binding and translational control leading to global changes in cellular expression programs in general and in synaptic plasticity in particular. Therefore, we focus on RBP dysfunction and how this might cause neuropsychiatric and neurodegenerative disorders. Based on recent findings, we propose that alterations in the entire regulatory RBP network might account for phenotypic dysfunctions observed in complex diseases including neurodegeneration, epilepsy, and autism spectrum disorders.
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Affiliation(s)
- Rico Schieweck
- Biomedical Center (BMC), Department for Cell Biology and Anatomy, Medical Faculty, Ludwig-Maximilians-University, Planegg-Martinsried, Germany
| | - Jovica Ninkovic
- Biomedical Center (BMC), Department for Cell Biology and Anatomy, Medical Faculty, Ludwig-Maximilians-University, Planegg-Martinsried, Germany
| | - Michael A Kiebler
- Biomedical Center (BMC), Department for Cell Biology and Anatomy, Medical Faculty, Ludwig-Maximilians-University, Planegg-Martinsried, Germany
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14
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Saini H, Bicknell AA, Eddy SR, Moore MJ. Free circular introns with an unusual branchpoint in neuronal projections. eLife 2019; 8:e47809. [PMID: 31697236 PMCID: PMC6879206 DOI: 10.7554/elife.47809] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2019] [Accepted: 11/06/2019] [Indexed: 12/22/2022] Open
Abstract
The polarized structure of axons and dendrites in neuronal cells depends in part on RNA localization. Previous studies have looked at which polyadenylated RNAs are enriched in neuronal projections or at synapses, but less is known about the distribution of non-adenylated RNAs. By physically dissecting projections from cell bodies of primary rat hippocampal neurons and sequencing total RNA, we found an unexpected set of free circular introns with a non-canonical branchpoint enriched in neuronal projections. These introns appear to be tailless lariats that escape debranching. They lack ribosome occupancy, sequence conservation, and known localization signals, and their function, if any, is not known. Nonetheless, their enrichment in projections has important implications for our understanding of the mechanisms by which RNAs reach distal compartments of asymmetric cells.
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Affiliation(s)
- Harleen Saini
- RNA Therapeutics InstituteUniversity of Massachusetts Medical SchoolWorcesterUnited States
- Department of Molecular and Cellular BiologyHoward Hughes Medical Institute, Harvard UniversityCambridgeUnited States
| | - Alicia A Bicknell
- RNA Therapeutics InstituteUniversity of Massachusetts Medical SchoolWorcesterUnited States
| | - Sean R Eddy
- Department of Molecular and Cellular BiologyHoward Hughes Medical Institute, Harvard UniversityCambridgeUnited States
- John A Paulson School of Engineering and Applied SciencesHarvard UniversityCambridgeUnited States
| | - Melissa J Moore
- RNA Therapeutics InstituteUniversity of Massachusetts Medical SchoolWorcesterUnited States
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15
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Abstract
PURPOSE OF REVIEW In the quest for understanding the pathophysiological processes underlying degeneration of nervous systems, synapses are emerging as sites of great interest as synaptic dysfunction is thought to play a role in the initiation and progression of neuronal loss. In particular, the synapse is an interesting target for the effects of epigenetic mechanisms in neurodegeneration. Here, we review the recent advances on epigenetic mechanisms driving synaptic compromise in major neurodegenerative disorders. RECENT FINDINGS Major developments in sequencing technologies enabled the mapping of transcriptomic patterns in human postmortem brain tissues in various neurodegenerative diseases, and also in cell and animal models. These studies helped identify changes in classical neurodegeneration pathways and discover novel targets related to synaptic degeneration. Identifying epigenetic patterns indicative of synaptic defects prior to neuronal degeneration may provide the basis for future breakthroughs in the field of neurodegeneration.
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Affiliation(s)
- Mary Xylaki
- Department of Experimental Neurodegeneration, Center for Biostructural Imaging of Neurodegeneration, University Medical Center Göttingen, Waldweg 33, 37073, Göttingen, Germany
| | - Benedict Atzler
- Department of Experimental Neurodegeneration, Center for Biostructural Imaging of Neurodegeneration, University Medical Center Göttingen, Waldweg 33, 37073, Göttingen, Germany
| | - Tiago Fleming Outeiro
- Department of Experimental Neurodegeneration, Center for Biostructural Imaging of Neurodegeneration, University Medical Center Göttingen, Waldweg 33, 37073, Göttingen, Germany.
- Max Planck Institute for Experimental Medicine, 37075, Göttingen, Germany.
- Institute of Neuroscience, The Medical School, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK.
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16
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Wolfe SA, Farris SP, Mayfield JE, Heaney CF, Erickson EK, Harris RA, Mayfield RD, Raab-Graham KF. Ethanol and a rapid-acting antidepressant produce overlapping changes in exon expression in the synaptic transcriptome. Neuropharmacology 2018; 146:289-299. [PMID: 30419244 DOI: 10.1016/j.neuropharm.2018.11.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Revised: 10/03/2018] [Accepted: 11/07/2018] [Indexed: 01/02/2023]
Abstract
Alcohol use disorder (AUD) and major depressive disorder (MDD) are prevalent, debilitating, and highly comorbid disorders. The molecular changes that underlie their comorbidity are beginning to emerge. For example, recent evidence showed that acute ethanol exposure produces rapid antidepressant-like biochemical and behavioral responses. Both ethanol and fast-acting antidepressants block N-methyl-D-aspartate receptor (NMDAR) activity, leading to synaptic changes and long-lasting antidepressant-like behavioral effects. We used RNA sequencing to analyze changes in the synaptic transcriptome after acute treatment with ethanol or the NMDAR antagonist, Ro 25-6981. Ethanol and Ro 25-6981 induced differential, independent changes in gene expression. In contrast with gene-level expression, ethanol and Ro 25-6981 produced overlapping changes in exons, as measured by analysis of differentially expressed exons (DEEs). A prominent overlap in genes with DEEs indicated that changes in exon usage were important for both ethanol and Ro 25-6981 action. Structural modeling provided evidence that ethanol-induced exon expression in the NMDAR1 amino-terminal domain could induce conformational changes and thus alter NMDAR function. These findings suggest that the rapid antidepressant effects of ethanol and NMDAR antagonists reported previously may depend on synaptic exon usage rather than gene expression.
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Affiliation(s)
- Sarah A Wolfe
- Committee on the Neurobiology of Addictive Disorders, The Scripps Research Institute, La Jolla, CA, 92037, United States
| | - Sean P Farris
- Waggoner Center for Alcohol and Addiction Research, Department of Neuroscience, University of Texas at Austin, 2500 Speedway, Austin, TX, 78712, United States
| | - Joshua E Mayfield
- Department of Molecular Biosciences, University of Texas at Austin, 2500 Speedway, Austin, TX, 78712, United States
| | - Chelcie F Heaney
- Department of Physiology and Pharmacology, Wake Forest University Health Sciences, Medical Center Boulevard, Winston-Salem, NC, 27157-1083, United States
| | - Emma K Erickson
- Waggoner Center for Alcohol and Addiction Research, Department of Neuroscience, University of Texas at Austin, 2500 Speedway, Austin, TX, 78712, United States
| | - R Adron Harris
- Waggoner Center for Alcohol and Addiction Research, Department of Neuroscience, University of Texas at Austin, 2500 Speedway, Austin, TX, 78712, United States
| | - R Dayne Mayfield
- Waggoner Center for Alcohol and Addiction Research, Department of Neuroscience, University of Texas at Austin, 2500 Speedway, Austin, TX, 78712, United States
| | - Kimberly F Raab-Graham
- Department of Physiology and Pharmacology, Wake Forest University Health Sciences, Medical Center Boulevard, Winston-Salem, NC, 27157-1083, United States.
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17
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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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18
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Izumikawa K, Ishikawa H, Simpson RJ, Takahashi N. Modulating the expression of Chtop, a versatile regulator of gene-specific transcription and mRNA export. RNA Biol 2018; 15:849-855. [PMID: 29683372 DOI: 10.1080/15476286.2018.1465795] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022] Open
Abstract
Chtop binds competitively to the arginine methyltransferases PRMT1 and PRMT5, thereby promoting the asymmetric or symmetric methylation of arginine residues, respectively. In cooperation with PRMT1, Chtop activates transcription of certain gene groups, such as the estrogen-inducible genes in breast cancer cells, the 5-hydroxymethylcytosine-modified genes involved in glioblastomagenesis, or the Zbp-89-dependent genes in erythroleukemia cells. Chtop also represses expression of the fetal γ-globin gene. In addition, Chtop is a component of the TREX complex that links transcription elongation to mRNA export. The regulation of Chtop expression is, therefore, a key process during the expression of certain gene groups and pathogenesis of certain diseases. Our recent study revealed that cellular levels of Chtop are strictly autoregulated by a mechanism involving intron retention and nonsense-mediated mRNA decay. Here, we summarize roles of Chtop in gene-specific expression and highlight our recent findings concerning the autoregulation of Chtop.
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Affiliation(s)
- Keiichi Izumikawa
- a Department of Applied Biological Science , United Graduate School of Agriculture, Tokyo University of Agriculture and Technology , Fuchu , Tokyo , Japan
| | - Hideaki Ishikawa
- a Department of Applied Biological Science , United Graduate School of Agriculture, Tokyo University of Agriculture and Technology , Fuchu , Tokyo , Japan
| | - Richard J Simpson
- b Global Innovation Research Organizations, Tokyo University of Agriculture and Technology , Fuchu , Tokyo , Japan.,c La Trobe Institute for Molecular Science (LIMS) LIMS Building 1, Room 412 La Trobe University , Bundoora Victoria , Australia
| | - Nobuhiro Takahashi
- a Department of Applied Biological Science , United Graduate School of Agriculture, Tokyo University of Agriculture and Technology , Fuchu , Tokyo , Japan.,b Global Innovation Research Organizations, Tokyo University of Agriculture and Technology , Fuchu , Tokyo , Japan
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19
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Tushev G, Glock C, Heumüller M, Biever A, Jovanovic M, Schuman EM. Alternative 3' UTRs Modify the Localization, Regulatory Potential, Stability, and Plasticity of mRNAs in Neuronal Compartments. Neuron 2018; 98:495-511.e6. [PMID: 29656876 DOI: 10.1016/j.neuron.2018.03.030] [Citation(s) in RCA: 225] [Impact Index Per Article: 37.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Revised: 01/20/2018] [Accepted: 03/16/2018] [Indexed: 02/07/2023]
Abstract
Neurons localize mRNAs near synapses where their translation can be regulated by synaptic demand and activity. Differences in the 3' UTRs of mRNAs can change their localization, stability, and translational regulation. Using 3' end RNA sequencing of microdissected rat brain slices, we discovered a huge diversity in mRNA 3' UTRs, with many transcripts showing enrichment for a particular 3' UTR isoform in either somata or the neuropil. The 3' UTR isoforms of localized transcripts are significantly longer than the 3' UTRs of non-localized transcripts and often code for proteins associated with axons, dendrites, and synapses. Surprisingly, long 3' UTRs add not only new, but also duplicate regulatory elements. The neuropil-enriched 3' UTR isoforms have significantly longer half-lives than somata-enriched isoforms. Finally, the 3' UTR isoforms can be significantly altered by enhanced activity. Most of the 3' UTR plasticity is transcription dependent, but intriguing examples of changes that are consistent with altered stability, trafficking between compartments, or local "remodeling" remain.
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Affiliation(s)
- Georgi Tushev
- Max Planck Institute for Brain Research, Frankfurt am Main, Germany
| | - Caspar Glock
- Max Planck Institute for Brain Research, Frankfurt am Main, Germany
| | | | - Anne Biever
- Max Planck Institute for Brain Research, Frankfurt am Main, Germany
| | - Marko Jovanovic
- Max Planck Institute for Brain Research, Frankfurt am Main, Germany
| | - Erin M Schuman
- Max Planck Institute for Brain Research, Frankfurt am Main, Germany.
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20
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Vanichkina DP, Schmitz U, Wong JJL, Rasko JE. Challenges in defining the role of intron retention in normal biology and disease. Semin Cell Dev Biol 2018; 75:40-49. [DOI: 10.1016/j.semcdb.2017.07.030] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Revised: 07/19/2017] [Accepted: 07/19/2017] [Indexed: 10/19/2022]
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21
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Plasticity of intrinsic excitability during LTD is mediated by bidirectional changes in h-channel activity. Sci Rep 2017; 7:14418. [PMID: 29089586 PMCID: PMC5663755 DOI: 10.1038/s41598-017-14874-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Accepted: 10/18/2017] [Indexed: 11/12/2022] Open
Abstract
The polarity of excitability changes associated with induction of Long-Term synaptic Depression (LTD) in CA1 pyramidal neurons is a contentious issue. Postsynaptic neuronal excitability after LTD induction is found to be reduced in certain cases (i.e. synergistic changes) but enhanced in others (i.e. compensatory or homeostatic). We examined here whether these divergent findings could result from the activation of two separate mechanisms converging onto a single learning rule linking synergistic and homeostatic plasticity. We show that the magnitude of LTD induced with low frequency stimulation (LFS) of the Schaffer collaterals determines the polarity of intrinsic changes in CA1 pyramidal neurons. Apparent input resistance (Rin) is reduced following induction of moderate LTD (<20–30%). In contrast, Rin is increased after induction of large LTD (>40%) induced by repetitive episodes of LFS. The up-regulation of Ih observed after moderate LTD results from the activation of NMDA receptors whereas the down-regulation of Ih is due to activation of mGluR1 receptors. These changes in Rin were associated with changes in intrinsic excitability. In conclusion, our study indicates that changes in excitability after LTD induction follow a learning rule describing a continuum linking synergistic and compensatory changes in excitability.
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22
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Paces J, Nic M, Novotny T, Svoboda P. Literature review of baseline information to support the risk assessment of RNAi‐based GM plants. ACTA ACUST UNITED AC 2017. [PMCID: PMC7163844 DOI: 10.2903/sp.efsa.2017.en-1246] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Jan Paces
- Institute of Molecular Genetics of the Academy of Sciences of the Czech Republic (IMG)
| | | | | | - Petr Svoboda
- Institute of Molecular Genetics of the Academy of Sciences of the Czech Republic (IMG)
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23
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Thomas-Jinu S, Gordon PM, Fielding T, Taylor R, Smith BN, Snowden V, Blanc E, Vance C, Topp S, Wong CH, Bielen H, Williams KL, McCann EP, Nicholson GA, Pan-Vazquez A, Fox AH, Bond CS, Talbot WS, Blair IP, Shaw CE, Houart C. Non-nuclear Pool of Splicing Factor SFPQ Regulates Axonal Transcripts Required for Normal Motor Development. Neuron 2017; 94:322-336.e5. [PMID: 28392072 PMCID: PMC5405110 DOI: 10.1016/j.neuron.2017.03.026] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Revised: 01/02/2017] [Accepted: 03/17/2017] [Indexed: 12/12/2022]
Abstract
Recent progress revealed the complexity of RNA processing and its association to human disorders. Here, we unveil a new facet of this complexity. Complete loss of function of the ubiquitous splicing factor SFPQ affects zebrafish motoneuron differentiation cell autonomously. In addition to its nuclear localization, the protein unexpectedly localizes to motor axons. The cytosolic version of SFPQ abolishes motor axonal defects, rescuing key transcripts, and restores motility in the paralyzed sfpq null mutants, indicating a non-nuclear processing role in motor axons. Novel variants affecting the conserved coiled-coil domain, so far exclusively found in fALS exomes, specifically affect the ability of SFPQ to localize in axons. They broadly rescue morphology and motility in the zebrafish mutant, but alter motor axon morphology, demonstrating functional requirement for axonal SFPQ. Altogether, we uncover the axonal function of the splicing factor SFPQ in motor development and highlight the importance of the coiled-coil domain in this process. Video Abstract
SFPQ splicing factor is present in motor axons Non-nuclear SFPQ is able to drive axon maturation and connectivity Loss of axonal SFPQ affects axonal morphology Coiled-coil domain of the protein is important for non-nuclear localization
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Affiliation(s)
- Swapna Thomas-Jinu
- Centre for Developmental Neurobiology and MRC CNDD, IoPPN, Guy's Campus, King's College London, London SE1 1UL, UK
| | - Patricia M Gordon
- Centre for Developmental Neurobiology and MRC CNDD, IoPPN, Guy's Campus, King's College London, London SE1 1UL, UK
| | - Triona Fielding
- Centre for Developmental Neurobiology and MRC CNDD, IoPPN, Guy's Campus, King's College London, London SE1 1UL, UK
| | - Richard Taylor
- Centre for Developmental Neurobiology and MRC CNDD, IoPPN, Guy's Campus, King's College London, London SE1 1UL, UK
| | - Bradley N Smith
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology, and Neuroscience, King's College London, London SE5 8AF, UK
| | - Victoria Snowden
- Centre for Developmental Neurobiology and MRC CNDD, IoPPN, Guy's Campus, King's College London, London SE1 1UL, UK
| | - Eric Blanc
- Centre for Developmental Neurobiology and MRC CNDD, IoPPN, Guy's Campus, King's College London, London SE1 1UL, UK
| | - Caroline Vance
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology, and Neuroscience, King's College London, London SE5 8AF, UK
| | - Simon Topp
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology, and Neuroscience, King's College London, London SE5 8AF, UK
| | - Chun-Hao Wong
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology, and Neuroscience, King's College London, London SE5 8AF, UK
| | - Holger Bielen
- Centre for Developmental Neurobiology and MRC CNDD, IoPPN, Guy's Campus, King's College London, London SE1 1UL, UK
| | - Kelly L Williams
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW 2109, Australia
| | - Emily P McCann
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW 2109, Australia
| | - Garth A Nicholson
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW 2109, Australia; ANZAC Research Institute, University of Sydney, Concord Hospital, Sydney, NSW 2139, Australia
| | - Alejandro Pan-Vazquez
- Centre for Developmental Neurobiology and MRC CNDD, IoPPN, Guy's Campus, King's College London, London SE1 1UL, UK
| | - Archa H Fox
- School of Anatomy, Physiology, and Human Biology, University of Western Australia, Crawley, WA 6009, Australia; Harry Perkins Institute for Medical Research, QEII Medical Centre, Nedlands, WA 6009, Australia; Centre for Medical Research, University of Western Australia, Crawley, WA 6009, Australia
| | - Charles S Bond
- School of Chemistry and Biochemistry, University of Western Australia, Crawley, WA 6009, Australia
| | - William S Talbot
- Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Ian P Blair
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW 2109, Australia
| | - Christopher E Shaw
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology, and Neuroscience, King's College London, London SE5 8AF, UK
| | - Corinne Houart
- Centre for Developmental Neurobiology and MRC CNDD, IoPPN, Guy's Campus, King's College London, London SE1 1UL, UK.
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24
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Role of Splice Variants of Gtf2i, a Transcription Factor Localizing at Postsynaptic Sites, and Its Relation to Neuropsychiatric Diseases. Int J Mol Sci 2017; 18:ijms18020411. [PMID: 28212274 PMCID: PMC5343945 DOI: 10.3390/ijms18020411] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2016] [Revised: 02/01/2017] [Accepted: 02/09/2017] [Indexed: 12/17/2022] Open
Abstract
We previously reported that various mRNAs were associated with postsynaptic density (PSD) purified from rat forebrain. Among the thousands of PSD-associated mRNAs, we highlight the biology of the general transcription factor II-I (Gtf2i) mRNA, focusing on the significance of its versatile splicing for targeting its own mRNA into dendrites, regulation of translation, and the effects of Gtf2i expression level as well as its relationship with neuropsychiatric disorders.
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25
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Huang X, Luo YL, Mao YS, Ji JL. The link between long noncoding RNAs and depression. Prog Neuropsychopharmacol Biol Psychiatry 2017; 73:73-78. [PMID: 27318257 DOI: 10.1016/j.pnpbp.2016.06.004] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/28/2015] [Revised: 06/07/2016] [Accepted: 06/13/2016] [Indexed: 12/28/2022]
Abstract
The major depressive disorder (MDD) is a relatively common mental disorder from which that hundreds of million people have suffered, leading to displeasing life quality, which is characterized by health damage and even suicidal thoughts. The complicated development and functioning of MDD is still under exploration. Long noncoding RNA (lncRNAs) are highly expressed in the brain, could affect neural stem cell maintenance, neurogenesis and gliogenesis, brain patterning, synaptic and stress responses, and neural plasticity. The dysregulation of certain lncRNAs induces in neurodevelopmental, neurodegenerative and neuroimmunological disorders, primary brain tumors, and psychiatric diseases. Although advances have been made, no fully satisfactory treatments for major depression are available, further investigation is requested. And recently data showed that the expression level of the majority of lncRNAs demonstrated a clear tendency of upregulation, and the certain dysregulated miRNAs and lncRNAs in the MDD have been proved to have a co-synergism mechanism, that is why we speculate lncRNA might get the capability to regulate MDD. Few identified lncRNAs have been deeply studied in detailed experiments up until now, little predictions of their function have been raised, and further researches is calling for discover their signal pathway and related regulatory networks.
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Affiliation(s)
- Xiao Huang
- Department of Psychological Medicine, Zhongshan Hospital, Fudan University, Shanghai 200032, China
| | - Yan-Li Luo
- Department of Psychiatry, Tongji Hospital of Tongji University, Shanghai 200065, China
| | - Yue-Shi Mao
- Department of Neurology, Zhongshan Hospital, Fudan University, Shanghai 200032, China
| | - Jian-Lin Ji
- Department of Psychological Medicine, Zhongshan Hospital, Fudan University, Shanghai 200032, China.
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26
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Faus-Garriga J, Novoa I, Ozaita A. mTOR signaling in proteostasis and its relevance to autism spectrum disorders. AIMS BIOPHYSICS 2017. [DOI: 10.3934/biophy.2017.1.63] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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27
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Martin S, Bellora N, González-Vallinas J, Irimia M, Chebli K, de Toledo M, Raabe M, Eyras E, Urlaub H, Blencowe BJ, Tazi J. Preferential binding of a stable G3BP ribonucleoprotein complex to intron-retaining transcripts in mouse brain and modulation of their expression in the cerebellum. J Neurochem 2016; 139:349-368. [PMID: 27513819 DOI: 10.1111/jnc.13768] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Revised: 08/02/2016] [Accepted: 08/02/2016] [Indexed: 12/13/2022]
Abstract
Neuronal granules play an important role in the localization and transport of translationally silenced messenger ribonucleoproteins in neurons. Among the factors associated with these granules, the RNA-binding protein G3BP1 (stress-granules assembly factor) is involved in neuronal plasticity and is induced in Alzheimer's disease. We immunopurified a stable complex containing G3BP1 from mouse brain and performed high-throughput sequencing and cross-linking immunoprecipitation to identify the associated RNAs. The G3BP-complex contained the deubiquitinating protease USP10, CtBP1 and the RNA-binding proteins Caprin-1, G3BP2a and splicing factor proline and glutamine rich, or PSF. The G3BP-complex binds preferentially to transcripts that retain introns, and to non-coding sequences like 3'-untranslated region and long non-coding RNAs. Specific transcripts with retained introns appear to be enriched in the cerebellum compared to the rest of the brain and G3BP1 depletion decreased this intron retention in the cerebellum of G3BP1 knockout mice. Among the enriched transcripts, we found an overrepresentation of genes involved in synaptic transmission, especially glutamate-related neuronal transmission. Notably, G3BP1 seems to repress the expression of the mature Grm5 (metabotropic glutamate receptor 5) transcript, by promoting the retention of an intron in the immature transcript in the cerebellum. Our results suggest that G3BP is involved in a new functional mechanism to regulate non-coding RNAs including intron-retaining transcripts, and thus have broad implications for neuronal gene regulation, where intron retention is widespread.
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Affiliation(s)
- Sophie Martin
- Institut de Génétique Moléculaire de Montpellier, CNRS UMR5535, Montpellier, France
| | - Nicolas Bellora
- Computational Genomics Group Universitat Pompeu Fabra PRBB, Barcelona, Spain.,Laboratorio de Microbiología Aplicada y Biotecnología, Instituto Andino-Patagónico de Tecnologías Biológicas y Geoambientales (IPATEC), CONICET - UNComahue, Bariloche, Argentina
| | | | - Manuel Irimia
- The Donnelly Centre, University of Toronto, Toronto, Ontario, Canada
| | - Karim Chebli
- Institut de Génétique Moléculaire de Montpellier, CNRS UMR5535, Montpellier, France
| | - Marion de Toledo
- Institut de Génétique Moléculaire de Montpellier, CNRS UMR5535, Montpellier, France
| | - Monika Raabe
- Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - Eduardo Eyras
- Computational Genomics Group Universitat Pompeu Fabra PRBB, Barcelona, Spain.,Catalan Institution for Research and Advanced Studies (ICREA), Passeig Lluís Companys 23, Barcelona, Spain
| | - Henning Urlaub
- Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - Ben J Blencowe
- The Donnelly Centre, University of Toronto, Toronto, Ontario, Canada
| | - Jamal Tazi
- Institut de Génétique Moléculaire de Montpellier, CNRS UMR5535, Montpellier, France.
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28
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Cellular Deconstruction: Finding Meaning in Individual Cell Variation. Trends Cell Biol 2016; 25:569-578. [PMID: 26410403 DOI: 10.1016/j.tcb.2015.07.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Revised: 06/26/2015] [Accepted: 07/17/2015] [Indexed: 12/21/2022]
Abstract
The advent of single cell transcriptome analysis has permitted the discovery of cell-to-cell variation in transcriptome expression of even presumptively identical cells. We hypothesize that this variability reflects a many-to-one relation between transcriptome states and the phenotype of a cell. In this relation, the molecular ratios of the subsets of RNA are determined by the stoichiometric constraints of the cell systems, which underdetermine the transcriptome state. Furthermore, the variability is, in part, induced by the tissue context and is important for system-level function. This theory is analogous to theories of literary deconstruction, where multiple 'signifiers' work in opposition to one another to create meaning. By analogy, transcriptome phenotypes should be defined as subsets of RNAs comprising selected RNA systems where the system-associated RNAs are balanced with each other to produce the associated cellular function. This idea provides a framework for understanding cellular heterogeneity in phenotypic responses to variant conditions, such as disease challenge.
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29
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Berto S, Usui N, Konopka G, Fogel BL. ELAVL2-regulated transcriptional and splicing networks in human neurons link neurodevelopment and autism. Hum Mol Genet 2016; 25:2451-2464. [PMID: 27260404 DOI: 10.1093/hmg/ddw110] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Revised: 03/01/2016] [Accepted: 04/04/2016] [Indexed: 01/31/2023] Open
Abstract
The role of post-transcriptional gene regulation in human brain development and neurodevelopmental disorders remains mostly uncharacterized. ELAV-like RNA-binding proteins (RNAbps) are a family of proteins that regulate several aspects of neuronal function including neuronal excitability and synaptic transmission, both critical to the normal function of the brain in cognition and behavior. Here, we identify the downstream neuronal transcriptional and splicing networks of ELAVL2, an RNAbp with previously unknown function in the brain. Expression of ELAVL2 was reduced in human neurons and RNA-sequencing was utilized to identify networks of differentially expressed and alternatively spliced genes resulting from haploinsufficient levels of ELAVL2. These networks contain a number of autism-relevant genes as well as previously identified targets of other important RNAbps implicated in autism spectrum disorder (ASD) including RBFOX1 and FMRP. ELAVL2-regulated co-expression networks are also enriched for neurodevelopmental and synaptic genes, and include genes with human-specific patterns of expression in the frontal pole. Together, these data suggest that ELAVL2 regulation of transcript expression is critical for neuronal function and clinically relevant to ASD.
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Affiliation(s)
- Stefano Berto
- Department of Neuroscience, University of Texas Southwestern Medical School, 5323 Harry Hines Blvd, ND4.300, Dallas, TX 75390-9111, USA
| | - Noriyoshi Usui
- Department of Neuroscience, University of Texas Southwestern Medical School, 5323 Harry Hines Blvd, ND4.300, Dallas, TX 75390-9111, USA
| | - Genevieve Konopka
- Department of Neuroscience, University of Texas Southwestern Medical School, 5323 Harry Hines Blvd, ND4.300, Dallas, TX 75390-9111, USA
| | - Brent L Fogel
- Program in Neurogenetics and Departments of Neurology and Human Genetics, David Geffen School of Medicine, University of California Los Angeles, 695 Charles E. Young Drive South, Gonda Room 1206, Los Angeles, CA 90095, USA
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30
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Towards understanding pre-mRNA splicing mechanisms and the role of SR proteins. Gene 2016; 587:107-19. [PMID: 27154819 DOI: 10.1016/j.gene.2016.04.057] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Accepted: 04/30/2016] [Indexed: 01/04/2023]
Abstract
Alternative pre-mRNA splicing provides a source of vast protein diversity by removing non-coding sequences (introns) and accurately linking different exonic regions in the correct reading frame. The regulation of alternative splicing is essential for various cellular functions in both pathological and physiological conditions. In eukaryotic cells, this process is commonly used to increase proteomic diversity and to control gene expression either co- or post-transcriptionally. Alternative splicing occurs within a megadalton-sized, multi-component machine consisting of RNA and proteins; during the splicing process, this complex undergoes dynamic changes via RNA-RNA, protein-protein and RNA-protein interactions. Co-transcriptional splicing functionally integrates the transcriptional machinery, thereby enabling the two processes to influence one another, whereas post-transcriptional splicing facilitates the coupling of RNA splicing with post-splicing events. This review addresses the structural aspects of spliceosomes and the mechanistic implications of their stepwise assembly on the regulation of pre-mRNA splicing. Moreover, the role of phosphorylation-based, signal-induced changes in the regulation of the splicing process is demonstrated.
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31
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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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32
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Kocerha J, Dwivedi Y, Brennand KJ. Noncoding RNAs and neurobehavioral mechanisms in psychiatric disease. Mol Psychiatry 2015; 20:677-684. [PMID: 25824307 PMCID: PMC4440836 DOI: 10.1038/mp.2015.30] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Revised: 01/20/2015] [Accepted: 01/26/2015] [Indexed: 01/04/2023]
Abstract
The human genome project has revolutionized our understanding of the underlying mechanisms in psychiatric disease. It is now abundantly clear that neurobehavioral phenotypes are epigenetically controlled by noncoding RNAs (ncRNAs). The microRNA (miRNA) class of ncRNAs are ubiquitously expressed throughout the brain and govern all major neuronal pathways. The attractive therapeutic potential of miRNAs is underscored by their pleiotropic capacities, putatively targeting multiple pathways within a single neuron. Many psychiatric diseases stem from a multifactorial origin, thus conventional drug targeting of single proteins may not prove most effective. In this exciting post-genome sequencing era, many new epigenetic targets are emerging for therapeutic investigation. Here we review the reported roles of miRNAs, as well as other ncRNA classes, in the pathology of psychiatric disorders; there are both common and unique ncRNA mechanisms that influence the various diagnoses. Collectively, these potent epigenetic regulators may clarify the disrupted signaling networks in psychiatric phenotypes.
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Affiliation(s)
- Jannet Kocerha
- Department of Chemistry, Georgia Southern University, PO Box 8064, Statesboro, GA 30460, USA
| | - Yogesh Dwivedi
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, 1720 2nd Avenue South, Birmingham, AL 35294-0017
| | - Kristen J Brennand
- Departments of Psychiatry and Neuroscience, Icahn School of Medicine at Mount Sinai, 1425 Madison Ave, 9-20B New York, NY 10029, USA
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33
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Smalheiser NR. The RNA-centred view of the synapse: non-coding RNAs and synaptic plasticity. Philos Trans R Soc Lond B Biol Sci 2015; 369:rstb.2013.0504. [PMID: 25135965 PMCID: PMC4142025 DOI: 10.1098/rstb.2013.0504] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
If mRNAs were the only RNAs made by a neuron, there would be a simple mapping of mRNAs to proteins. However, microRNAs and other non-coding RNAs (ncRNAs; endo-siRNAs, piRNAs, BC1, BC200, antisense and long ncRNAs, repeat-related transcripts, etc.) regulate mRNAs via effects on protein translation as well as transcriptional and epigenetic mechanisms. Not only are genes ON or OFF, but their ability to be translated can be turned ON or OFF at the level of synapses, supporting an enormous increase in information capacity. Here, I review evidence that ncRNAs are expressed pervasively within dendrites in mammalian brain; that some are activity-dependent and highly enriched near synapses; and that synaptic ncRNAs participate in plasticity responses including learning and memory. Ultimately, ncRNAs can be viewed as the post-it notes of the neuron. They have no literal meaning of their own, but derive their functions from where (and to what) they are stuck. This may explain, in part, why ncRNAs differ so dramatically from protein-coding genes, both in terms of the usual indicators of functionality and in terms of evolutionary constraints. ncRNAs do not appear to be direct mediators of synaptic transmission in the manner of neurotransmitters or receptors, yet they orchestrate synaptic plasticity—and may drive species-specific changes in cognition.
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Affiliation(s)
- Neil R Smalheiser
- Department of Psychiatry, University of Illinois at Chicago, Chicago, IL 60612, USA
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34
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Sharif SR, Lee H, Islam MA, Seog DH, Moon IS. N-acetyl-D-glucosamine kinase is a component of nuclear speckles and paraspeckles. Mol Cells 2015; 38:402-8. [PMID: 25921606 PMCID: PMC4443281 DOI: 10.14348/molcells.2015.2242] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2014] [Revised: 02/09/2015] [Accepted: 02/11/2015] [Indexed: 11/27/2022] Open
Abstract
Protein O-GlcNAcylation, dictated by cellular UDP-N-acetylglucosamine (UDP-GlcNAc) levels, plays a crucial role in posttranslational modifications. The enzyme GlcNAc kinase (NAGK, E.C. 2.7.1.59) catalyzes the formation of GlcNAc-6-phosphate, which is a major substrate for the biosynthesis of UDP-GlcNAc. Recent studies have revealed the expression of NAGK in different types of cells especially in neuronal dendrites. Here, by immunocytochemistry (ICC) and immunonucleochemistry (INC) of cultured rat hippocampal neurons, HEK293T and GT1-7 cells, we have showed that NAGK immuno-reactive punctae being present in the nucleoplasm colocalized with small nuclear ribonucleoprotein-associated protein N (snRNPN) and p54NRB, which are speckle and paraspeckle markers, respectively. Furthermore, NAGK IR cluster was also found to be colocalized with GTF2H5 (general transcription factor IIH, polypeptide 5) immuno reactive punctae. In addition, relative localization to the ring of nuclear lamin matrix and to GlcNAc, which is highly enriched in nuclear pore complexes, showed that NAGK surrounds the nucleus at the cytoplasmic face of the nuclear outer membrane. By in situ proximity ligation assay (PLA) we confirmed the colocalization of NAGK with snRNPN in the nucleus and in dendrites, while we also verified the interactions of NAGK with p54NRB, and with GTF2H5 in the nucleus. These associations between NAGK with speckle, paraspeckle and general transcription factor suggest its regulatory roles in gene expression.
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Affiliation(s)
- Syeda Ridita Sharif
- Department of Anatomy, Dongguk Medical Institute, Dongguk University College of Medicine, Gyeongju 780-714,
Korea
| | - HyunSook Lee
- Dongguk Medical Institute, Dongguk University College of Medicine, Gyeongju 780-714,
Korea
| | - Md. Ariful Islam
- Department of Anatomy, Dongguk Medical Institute, Dongguk University College of Medicine, Gyeongju 780-714,
Korea
| | - Dae-Hyun Seog
- Department of Biochemistry, College of Medicine, Inje University, Busan 614-735,
Korea
| | - Il Soo Moon
- Department of Anatomy, Dongguk Medical Institute, Dongguk University College of Medicine, Gyeongju 780-714,
Korea
- Dongguk Medical Institute, Dongguk University College of Medicine, Gyeongju 780-714,
Korea
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35
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Mammalian introns: when the junk generates molecular diversity. Int J Mol Sci 2015; 16:4429-52. [PMID: 25710723 PMCID: PMC4394429 DOI: 10.3390/ijms16034429] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Revised: 02/06/2015] [Accepted: 02/11/2015] [Indexed: 01/14/2023] Open
Abstract
Introns represent almost half of the human genome, yet their vast majority is eliminated from eukaryotic transcripts through RNA splicing. Nevertheless, they feature key elements and functions that deserve further interest. At the level of DNA, introns are genomic segments that can shelter independent transcription units for coding and non-coding RNAs which transcription may interfere with that of the host gene, and regulatory elements that can influence gene expression and splicing itself. From the RNA perspective, some introns can be subjected to alternative splicing. Intron retention appear to provide some plasticity to the nature of the protein produced, its distribution in a given cell type and timing of its translation. Intron retention may also serve as a switch to produce coding or non-coding RNAs from the same transcription unit. Conversely, splicing of introns has been directly implicated in the production of small regulatory RNAs. Hence, splicing of introns also appears to provide plasticity to the type of RNA produced from a genetic locus (coding, non-coding, short or long). We addressed these aspects to add to our understanding of mechanisms that control the fate of introns and could be instrumental in regulating genomic output and hence cell fate.
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36
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Antonacci S, Forand D, Wolf M, Tyus C, Barney J, Kellogg L, Simon MA, Kerr G, Wells KL, Younes S, Mortimer NT, Olesnicky EC, Killian DJ. Conserved RNA-binding proteins required for dendrite morphogenesis in Caenorhabditis elegans sensory neurons. G3 (BETHESDA, MD.) 2015; 5:639-53. [PMID: 25673135 PMCID: PMC4390579 DOI: 10.1534/g3.115.017327] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Accepted: 02/09/2015] [Indexed: 01/22/2023]
Abstract
The regulation of dendritic branching is critical for sensory reception, cell-cell communication within the nervous system, learning, memory, and behavior. Defects in dendrite morphology are associated with several neurologic disorders; thus, an understanding of the molecular mechanisms that govern dendrite morphogenesis is important. Recent investigations of dendrite morphogenesis have highlighted the importance of gene regulation at the posttranscriptional level. Because RNA-binding proteins mediate many posttranscriptional mechanisms, we decided to investigate the extent to which conserved RNA-binding proteins contribute to dendrite morphogenesis across phyla. Here we identify a core set of RNA-binding proteins that are important for dendrite morphogenesis in the PVD multidendritic sensory neuron in Caenorhabditis elegans. Homologs of each of these genes were previously identified as important in the Drosophila melanogaster dendritic arborization sensory neurons. Our results suggest that RNA processing, mRNA localization, mRNA stability, and translational control are all important mechanisms that contribute to dendrite morphogenesis, and we present a conserved set of RNA-binding proteins that regulate these processes in diverse animal species. Furthermore, homologs of these genes are expressed in the human brain, suggesting that these RNA-binding proteins are candidate regulators of dendrite development in humans.
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Affiliation(s)
- Simona Antonacci
- Department of Molecular Biology, Colorado College, Colorado Springs, Colorado 80903
| | - Daniel Forand
- Department of Biology, University of Colorado Colorado Springs, Colorado Springs, Colorado 80918
| | - Margaret Wolf
- Department of Molecular Biology, Colorado College, Colorado Springs, Colorado 80903
| | - Courtney Tyus
- Department of Molecular Biology, Colorado College, Colorado Springs, Colorado 80903
| | - Julia Barney
- Department of Molecular Biology, Colorado College, Colorado Springs, Colorado 80903
| | - Leah Kellogg
- Department of Molecular Biology, Colorado College, Colorado Springs, Colorado 80903
| | - Margo A Simon
- Department of Molecular Biology, Colorado College, Colorado Springs, Colorado 80903
| | - Genevieve Kerr
- Department of Molecular Biology, Colorado College, Colorado Springs, Colorado 80903
| | - Kristen L Wells
- Department of Molecular Biology, Colorado College, Colorado Springs, Colorado 80903
| | - Serena Younes
- Department of Biology, University of Colorado Colorado Springs, Colorado Springs, Colorado 80918
| | - Nathan T Mortimer
- Department of Biological Sciences, University of Denver, Denver, Colorado 80208
| | - Eugenia C Olesnicky
- Department of Biology, University of Colorado Colorado Springs, Colorado Springs, Colorado 80918
| | - Darrell J Killian
- Department of Molecular Biology, Colorado College, Colorado Springs, Colorado 80903
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Diner I, Hales CM, Bishof I, Rabenold L, Duong DM, Yi H, Laur O, Gearing M, Troncoso J, Thambisetty M, Lah JJ, Levey AI, Seyfried NT. Aggregation properties of the small nuclear ribonucleoprotein U1-70K in Alzheimer disease. J Biol Chem 2014; 289:35296-313. [PMID: 25355317 DOI: 10.1074/jbc.m114.562959] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Recent evidence indicates that U1-70K and other U1 small nuclear ribonucleoproteins are Sarkosyl-insoluble and associate with Tau neurofibrillary tangles selectively in Alzheimer disease (AD). Currently, the mechanisms underlying the conversion of soluble nuclear U1 small nuclear ribonucleoproteins into insoluble cytoplasmic aggregates remain elusive. Based on the biochemical and subcellular distribution properties of U1-70K in AD, we hypothesized that aggregated U1-70K itself or other biopolymers (e.g. proteins or nucleic acids) interact with and sequester natively folded soluble U1-70K into insoluble aggregates. Here, we demonstrate that total homogenates from AD brain induce soluble U1-70K from control brain or recombinant U1-70K to become Sarkosyl-insoluble. This effect was not dependent on RNA and did not correlate with detergent-insoluble Tau levels as AD homogenates with reduced levels of these components were still capable of inducing U1-70K aggregation. In contrast, proteinase K-treated AD homogenates and Sarkosyl-soluble AD fractions were unable to induce U1-70K aggregation, indicating that aggregated proteins in AD brain are responsible for inducing soluble U1-70K aggregation. It was determined that the C terminus of U1-70K, which harbors two disordered low complexity (LC) domains, is necessary for U1-70K aggregation. Moreover, both LC1 and LC2 domains were sufficient for aggregation. Finally, protein cross-linking and mass spectrometry studies demonstrated that a U1-70K fragment harboring the LC1 domain directly interacts with aggregated U1-70K in AD brain. Our results support a hypothesis that aberrant forms of U1-70K in AD can directly sequester soluble forms of U1-70K into insoluble aggregates.
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Affiliation(s)
- Ian Diner
- From the Departments of Biochemistry and the Center for Neurodegenerative Disease, Emory University School of Medicine, Atlanta, Georgia 30322
| | - Chadwick M Hales
- the Center for Neurodegenerative Disease, Emory University School of Medicine, Atlanta, Georgia 30322 Neurology
| | - Isaac Bishof
- From the Departments of Biochemistry and the Center for Neurodegenerative Disease, Emory University School of Medicine, Atlanta, Georgia 30322
| | - Lake Rabenold
- From the Departments of Biochemistry and the Center for Neurodegenerative Disease, Emory University School of Medicine, Atlanta, Georgia 30322
| | - Duc M Duong
- From the Departments of Biochemistry and the Center for Neurodegenerative Disease, Emory University School of Medicine, Atlanta, Georgia 30322
| | - Hong Yi
- Emory University School of Medicine, Atlanta, Georgia 30322 Robert P. Apkarian Integrated Electron Microscopy Core
| | - Oskar Laur
- Emory University School of Medicine, Atlanta, Georgia 30322 Division of Microbiology, and Yerkes Research Center, Emory University, Atlanta, Georgia 30322
| | - Marla Gearing
- the Center for Neurodegenerative Disease, Emory University School of Medicine, Atlanta, Georgia 30322 the Departments of Experimental Pathology and
| | - Juan Troncoso
- Pathology and Neurology, Johns Hopkins School of Medicine, Baltimore, Maryland 21205
| | | | - James J Lah
- the Center for Neurodegenerative Disease, Emory University School of Medicine, Atlanta, Georgia 30322 Neurology
| | - Allan I Levey
- the Center for Neurodegenerative Disease, Emory University School of Medicine, Atlanta, Georgia 30322 Neurology
| | - Nicholas T Seyfried
- From the Departments of Biochemistry and the Center for Neurodegenerative Disease, Emory University School of Medicine, Atlanta, Georgia 30322 Neurology,
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38
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Francis C, Natarajan S, Lee MT, Khaladkar M, Buckley PT, Sul JY, Eberwine J, Kim J. Divergence of RNA localization between rat and mouse neurons reveals the potential for rapid brain evolution. BMC Genomics 2014; 15:883. [PMID: 25301173 PMCID: PMC4203888 DOI: 10.1186/1471-2164-15-883] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2013] [Accepted: 09/23/2014] [Indexed: 12/12/2022] Open
Abstract
Background Neurons display a highly polarized architecture. Their ability to modify their features under intracellular and extracellular stimuli, known as synaptic plasticity, is a key component of the neurochemical basis of learning and memory. A key feature of synaptic plasticity involves the delivery of mRNAs to distinct sub-cellular domains where they are locally translated. Regulatory coordination of these spatio-temporal events is critical for synaptogenesis and synaptic plasticity as defects in these processes can lead to neurological diseases. In this work, using microdissected dendrites from primary cultures of hippocampal neurons of two mouse strains (C57BL/6 and Balb/c) and one rat strain (Sprague–Dawley), we investigate via microarrays, subcellular localization of mRNAs in dendrites of neurons to assay the evolutionary differences in subcellular dendritic transcripts localization. Results Our microarray analysis highlighted significantly greater evolutionary diversification of RNA localization in the dendritic transcriptomes (81% gene identity difference among the top 5% highly expressed genes) compared to the transcriptomes of 11 different central nervous system (CNS) and non-CNS tissues (average of 44% gene identity difference among the top 5% highly expressed genes). Differentially localized genes include many genes involved in CNS function. Conclusions Species differences in sub-cellular localization may reflect non-functional neutral drift. However, the functional categories of mRNA showing differential localization suggest that at least part of the divergence may reflect activity-dependent functional differences of neurons, mediated by species-specific RNA subcellular localization mechanisms. Electronic supplementary material The online version of this article (doi:10.1186/1471-2164-15-883) contains supplementary material, which is available to authorized users.
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Affiliation(s)
| | | | | | | | | | | | - James Eberwine
- Department of Biology, University of Pennsylvania, Philadelphia, PA 19104, USA.
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The synaptoneurosome transcriptome: a model for profiling the emolecular effects of alcohol. THE PHARMACOGENOMICS JOURNAL 2014; 15:177-88. [PMID: 25135349 DOI: 10.1038/tpj.2014.43] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2014] [Revised: 04/29/2014] [Accepted: 06/18/2014] [Indexed: 12/22/2022]
Abstract
Chronic alcohol consumption changes gene expression, likely causing persistent remodeling of synaptic structures via altered translation of mRNAs within synaptic compartments of the cell. We profiled the transcriptome from synaptoneurosomes (SNs) and paired total homogenates (THs) from mouse amygdala following chronic voluntary alcohol consumption. In SN, both the number of alcohol-responsive mRNAs and the magnitude of fold-change were greater than in THs, including many GABA-related mRNAs upregulated in SNs. Furthermore, SN gene co-expression analysis revealed a highly connected network, demonstrating coordinated patterns of gene expression and highlighting alcohol-responsive biological pathways, such as long-term potentiation, long-term depression, glutamate signaling, RNA processing and upregulation of alcohol-responsive genes within neuroimmune modules. Alterations in these pathways have also been observed in the amygdala of human alcoholics. SNs offer an ideal model for detecting intricate networks of coordinated synaptic gene expression and may provide a unique system for investigating therapeutic targets for the treatment of alcoholism.
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40
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Jung H, Gkogkas CG, Sonenberg N, Holt CE. Remote control of gene function by local translation. Cell 2014; 157:26-40. [PMID: 24679524 PMCID: PMC3988848 DOI: 10.1016/j.cell.2014.03.005] [Citation(s) in RCA: 235] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2013] [Revised: 02/04/2014] [Accepted: 03/04/2014] [Indexed: 12/12/2022]
Abstract
The subcellular position of a protein is a key determinant of its function. Mounting evidence indicates that RNA localization, where specific mRNAs are transported subcellularly and subsequently translated in response to localized signals, is an evolutionarily conserved mechanism to control protein localization. On-site synthesis confers novel signaling properties to a protein and helps to maintain local proteome homeostasis. Local translation plays particularly important roles in distal neuronal compartments, and dysregulated RNA localization and translation cause defects in neuronal wiring and survival. Here, we discuss key findings in this area and possible implications of this adaptable and swift mechanism for spatial control of gene function.
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Affiliation(s)
- Hosung Jung
- Department of Anatomy, Brain Research Institute, and Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul 120-752, South Korea
| | - Christos G Gkogkas
- Patrick Wild Centre, Centre for Integrative Physiology, Hugh Robson Building, University of Edinburgh, Edinburgh EH8 9XD, UK
| | - Nahum Sonenberg
- Department of Biochemistry and Goodman Cancer Research Centre, McGill University, Montreal, QC H3A 1A3, Canada.
| | - Christine E Holt
- Department of Physiology Development and Neuroscience, Anatomy Building, Downing Street, University of Cambridge, Cambridge CB2 3DY, UK.
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41
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Thomas MG, Pascual ML, Maschi D, Luchelli L, Boccaccio GL. Synaptic control of local translation: the plot thickens with new characters. Cell Mol Life Sci 2014; 71:2219-39. [PMID: 24212248 PMCID: PMC11113725 DOI: 10.1007/s00018-013-1506-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2013] [Revised: 10/11/2013] [Accepted: 10/21/2013] [Indexed: 12/18/2022]
Abstract
The production of proteins from mRNAs localized at the synapse ultimately controls the strength of synaptic transmission, thereby affecting behavior and cognitive functions. The regulated transcription, processing, and transport of mRNAs provide dynamic control of the dendritic transcriptome, which includes thousands of messengers encoding multiple cellular functions. Translation is locally modulated by synaptic activity through a complex network of RNA-binding proteins (RBPs) and various types of non-coding RNAs (ncRNAs) including BC-RNAs, microRNAs, piwi-interacting RNAs, and small interference RNAs. The RBPs FMRP and CPEB play a well-established role in synaptic translation, and additional regulatory factors are emerging. The mRNA repressors Smaug, Nanos, and Pumilio define a novel pathway for local translational control that affects dendritic branching and spines in both flies and mammals. Recent findings support a role for processing bodies and related synaptic mRNA-silencing foci (SyAS-foci) in the modulation of synaptic plasticity and memory formation. The SyAS-foci respond to different stimuli with changes in their integrity thus enabling regulated mRNA release followed by translation. CPEB, Pumilio, TDP-43, and FUS/TLS form multimers through low-complexity regions related to prion domains or polyQ expansions. The oligomerization of these repressor RBPs is mechanistically linked to the aggregation of abnormal proteins commonly associated with neurodegeneration. Here, we summarize the current knowledge on how specificity in mRNA translation is achieved through the concerted action of multiple pathways that involve regulatory ncRNAs and RBPs, the modification of translation factors, and mRNA-silencing foci dynamics.
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Affiliation(s)
- María Gabriela Thomas
- Instituto Leloir, Av. Patricias Argentinas 435, C1405BWE Buenos Aires, Argentina
- IIBBA-CONICET, C1405BWE Buenos Aires, Argentina
| | - Malena Lucía Pascual
- Instituto Leloir, Av. Patricias Argentinas 435, C1405BWE Buenos Aires, Argentina
- IIBBA-CONICET, C1405BWE Buenos Aires, Argentina
- Facultad de Ciencias Exactas y Naturales, University of Buenos Aires, Buenos Aires, Argentina
| | - Darío Maschi
- Instituto Leloir, Av. Patricias Argentinas 435, C1405BWE Buenos Aires, Argentina
- Present Address: Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO USA
| | - Luciana Luchelli
- Instituto Leloir, Av. Patricias Argentinas 435, C1405BWE Buenos Aires, Argentina
- IIBBA-CONICET, C1405BWE Buenos Aires, Argentina
| | - Graciela Lidia Boccaccio
- Instituto Leloir, Av. Patricias Argentinas 435, C1405BWE Buenos Aires, Argentina
- IIBBA-CONICET, C1405BWE Buenos Aires, Argentina
- Facultad de Ciencias Exactas y Naturales, University of Buenos Aires, Buenos Aires, Argentina
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42
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RNA-RNA interactions and pre-mRNA mislocalization as drivers of group II intron loss from nuclear genomes. Proc Natl Acad Sci U S A 2014; 111:6612-7. [PMID: 24722636 DOI: 10.1073/pnas.1404276111] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Group II introns are commonly believed to be the progenitors of spliceosomal introns, but they are notably absent from nuclear genomes. Barriers to group II intron function in nuclear genomes therefore beg examination. A previous study showed that nuclear expression of a group II intron in yeast results in nonsense-mediated decay and translational repression of mRNA, and that these roadblocks to expression are group II intron-specific. To determine the molecular basis for repression of gene expression, we investigated cellular dynamics of processed group II intron RNAs, from transcription to cellular localization. Our data show pre-mRNA mislocalization to the cytoplasm, where the RNAs are targeted to foci. Furthermore, tenacious mRNA-pre-mRNA interactions, based on intron-exon binding sequences, result in reduced abundance of spliced mRNAs. Nuclear retention of pre-mRNA prevents this interaction and relieves these expression blocks. In addition to providing a mechanistic rationale for group II intron-specific repression, our data support the hypothesis that RNA silencing of the host gene contributed to expulsion of group II introns from nuclear genomes and drove the evolution of spliceosomal introns.
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43
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Abstract
Several studies have shown that synthesis of new proteins at the synapse is a prerequisite for the storage of long-term memories. Relatively little is known about the availability of distinct mRNA populations for translation at specific synapses, the process that determines mRNA localization, and the temporal designations of localized mRNA translation during memory storage. Techniques such as synaptosome preparation and microdissection of distal neuronal processes of cultured neurons and dendritic layers in brain slices are general approaches used to identify localized RNAs. Exploration of the association of RNA-binding proteins to the axonal transport machinery has led to the development of a strategy to identify RNAs that are transported from the cell body to synapses by molecular motor kinesin. In this article, RNA localization at the synapse, as well as its mechanisms and significance in understanding long-term memory storage, are discussed.
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44
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Buckley PT, Khaladkar M, Kim J, Eberwine J. Cytoplasmic intron retention, function, splicing, and the sentinel RNA hypothesis. WILEY INTERDISCIPLINARY REVIEWS-RNA 2013; 5:223-30. [PMID: 24190870 DOI: 10.1002/wrna.1203] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2013] [Revised: 09/11/2013] [Accepted: 10/04/2013] [Indexed: 01/07/2023]
Abstract
Cytoplasmic splicing represents a newly emerging level of transcriptional regulation adding to the molecular diversity of mammalian cells. As examples of this noncanonical form of transcript processing are discovered, the evidence of its importance to normal cellular function grows. Work from a number of groups using a variety of cell types is steadily identifying a large number of transcripts (and soon to be even larger as genome-wide analyses of retained introns across a number of cellular phenotypes are currently underway) that undergo some level of regulated endogenous extranuclear splicing as part of their normal biosynthetic pathway. Here, we review the existing data covering cytoplasmic retained intron sequences and suggest that such sequences may be a component of 'sentinel RNA' that serves to generate transcript variants within the cytoplasm as well as a source for RNA-based secondary messages.
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Affiliation(s)
- Peter T Buckley
- Department of Pharmacology, Perelman School of Medicine and the School of Arts and Sciences, University of Pennsylvania, Philadelphia, PA, USA
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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: 442] [Impact Index Per Article: 40.2] [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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46
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Risbud RM, Porter BE. Changes in microRNA expression in the whole hippocampus and hippocampal synaptoneurosome fraction following pilocarpine induced status epilepticus. PLoS One 2013; 8:e53464. [PMID: 23308228 PMCID: PMC3538591 DOI: 10.1371/journal.pone.0053464] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2012] [Accepted: 11/30/2012] [Indexed: 01/09/2023] Open
Abstract
MicroRNAs regulate protein synthesis by binding non-translated regions of mRNAs and suppressing translation and/or increasing mRNA degradation. MicroRNAs play an important role in the nervous system including controlling synaptic plasticity. Their expression is altered in disease states including stroke, head injury and epilepsy. To better understand microRNA expression changes that might contribute to the development of epilepsy, microRNA arrays were performed on rat hippocampus 4 hours, 48 hours and 3 weeks following an episode of pilocarpine induced status epilepticus. Eighty microRNAs increased at one or more of the time points. No microRNAs decreased at 4 hours, and only a few decreased at 3 weeks, but 188 decreased 48 hours after status epilepticus. The large number of microRNAs with altered expression following status epilepticus suggests that microRNA regulation of translation has the potential to contribute to changes in protein expression during epileptogenesis. We carried out a second set of array's comparing microRNA expression at 48 hours in synaptoneurosome and nuclear fractions of the hippocampus. In control rat hippocampi multiple microRNAs were enriched in the synaptoneurosomal fraction as compared to the nuclear fraction. In contrast, 48 hours after status epilepticus only one microRNA was enriched in the synaptoneurosome fraction. The loss of microRNAs enriched in the synaptoneurosomal fraction implies a dramatic change in translational regulation in synapses 48 hours after status epilepticus.
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Affiliation(s)
- Rashmi M. Risbud
- Division of Pediatric Neurology, Department of Pediatrics, The Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, United States of America
| | - Brenda E. Porter
- Division of Pediatric Neurology, Department of Pediatrics, The Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, United States of America
- Division of Pediatric Neurology, Department of Neurology, The Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
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47
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Lugli G, Larson J, Demars MP, Smalheiser NR. Primary microRNA precursor transcripts are localized at post-synaptic densities in adult mouse forebrain. J Neurochem 2012; 123:459-66. [PMID: 22897173 DOI: 10.1111/j.1471-4159.2012.07921.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2012] [Revised: 05/22/2012] [Accepted: 08/13/2012] [Indexed: 11/29/2022]
Abstract
In a previous study, we reported that microRNA (miRNA) precursors are expressed in synaptic fractions within adult mouse forebrain, where they are enriched at post-synaptic densities (PSDs). However, because that study employed qRT-PCR primers that recognize the hairpin region, it was not able to distinguish between primary microRNA gene transcripts (pri-miRs) and small hairpin precursors (pre-miRs). Here, using primer sets that selectively measure regions upstream, downstream and flanking the hairpin, we demonstrate that pri-miRs are present in synaptic fractions (enriched several-fold relative to total tissue homogenate) and are especially enriched in isolated PSDs. Drosha and DGCR8 proteins are also expressed in synaptic fractions and PSDs, and are tightly associated with pri-miRs as assessed by coimmunoprecipitation under stringent conditions. Pri-miRs, drosha, and DGCR8 are highly enriched in fractions that contain mRNA transport particles, and cytosolic drosha is associated with kinesin heavy chain; these findings suggest that pri-miRs are transported to synaptic regions in a manner similar to mRNAs. This study supports the notion that miRNA biogenesis occurs locally near synapses in a regulated fashion.
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Affiliation(s)
- Giovanni Lugli
- Department of Psychiatry and Psychiatric Institute, University of Illinois at Chicago, Chicago, IL 60612, USA
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48
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Eberwine J, Lovatt D, Buckley P, Dueck H, Francis C, Kim TK, Lee J, Lee M, Miyashiro K, Morris J, Peritz T, Schochet T, Spaethling J, Sul JY, Kim J. Quantitative biology of single neurons. J R Soc Interface 2012; 9:3165-83. [PMID: 22915636 PMCID: PMC3481569 DOI: 10.1098/rsif.2012.0417] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
The building blocks of complex biological systems are single cells. Fundamental insights gained from single-cell analysis promise to provide the framework for understanding normal biological systems development as well as the limits on systems/cellular ability to respond to disease. The interplay of cells to create functional systems is not well understood. Until recently, the study of single cells has concentrated primarily on morphological and physiological characterization. With the application of new highly sensitive molecular and genomic technologies, the quantitative biochemistry of single cells is now accessible.
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Affiliation(s)
- James Eberwine
- Department of Pharmacology, Perelman School of Medicine, University of Pennsylvania, 36th and Hamilton Walk, Philadelphia, PA 19104, USA.
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49
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Pichardo-Casas I, Goff LA, Swerdel MR, Athie A, Davila J, Ramos-Brossier M, Lapid-Volosin M, Friedman WJ, Hart RP, Vaca L. Expression profiling of synaptic microRNAs from the adult rat brain identifies regional differences and seizure-induced dynamic modulation. Brain Res 2011; 1436:20-33. [PMID: 22197703 DOI: 10.1016/j.brainres.2011.12.001] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2011] [Revised: 11/24/2011] [Accepted: 12/01/2011] [Indexed: 12/01/2022]
Abstract
In recent years, microRNAs or miRNAs have been proposed to target neuronal mRNAs localized near the synapse, exerting a pivotal role in modulating local protein synthesis, and presumably affecting adaptive mechanisms such as synaptic plasticity. In the present study we have characterized the distribution of miRNAs in five regions of the adult mammalian brain and compared the relative abundance between total fractions and purified synaptoneurosomes (SN), using three different methodologies. The results show selective enrichment or depletion of some miRNAs when comparing total versus SN fractions. These miRNAs were different for each brain region explored. Changes in distribution could not be attributed to simple diffusion or to a targeting sequence inside the miRNAs. In silico analysis suggest that the differences in distribution may be related to the preferential concentration of synaptically localized mRNA targeted by the miRNAs. These results favor a model of co-transport of the miRNA-mRNA complex to the synapse, although further studies are required to validate this hypothesis. Using an in vivo model for increasing excitatory activity in the cortex and the hippocampus indicates that the distribution of some miRNAs can be modulated by enhanced neuronal (epileptogenic) activity. All these results demonstrate the dynamic modulation in the local distribution of miRNAs from the adult brain, which may play key roles in controlling localized protein synthesis at the synapse.
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Affiliation(s)
- Israel Pichardo-Casas
- Departamento de Biología Celular, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, México, DF México.
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50
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The intricate relationship between RNA structure, editing, and splicing. Semin Cell Dev Biol 2011; 23:281-8. [PMID: 22178616 DOI: 10.1016/j.semcdb.2011.11.004] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2011] [Revised: 11/15/2011] [Accepted: 11/17/2011] [Indexed: 11/23/2022]
Abstract
Post-transcriptional modifications such as RNA editing and splicing diversify the proteome while limiting the necessary size of the genome. Although splicing globally rearranges existing information within the transcript, the conserved process of adenosine-to-inosine RNA editing recodes the message through single nucleotide changes, often at very specific locations. Because inosine is interpreted as guanosine by the cellular machineries, editing effectively results in the substitution of a guanosine for an adenosine in the primary RNA sequence. Precise control of editing is dictated by duplex structures in the transcript, formed between the exonic region surrounding the editing site and cis regulatory elements often localized in a nearby intron, suggesting that editing must precede splicing. However, the precise relationship between these post-transcriptional processes remains unclear. Here we present general commonalities of RNA editing substrates and consequential predictions regarding the interaction between editing and splicing. We also discuss anomalies and interesting cases of RNA editing that confound our understanding of the relationship between these post-transcriptional processes.
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