1
|
Volianskis R, Lundbye CJ, Petroff GN, Jane DE, Georgiou J, Collingridge GL. Cage effects on synaptic plasticity and its modulation in a mouse model of fragile X syndrome. Philos Trans R Soc Lond B Biol Sci 2024; 379:20230484. [PMID: 38853552 DOI: 10.1098/rstb.2023.0484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Accepted: 04/08/2024] [Indexed: 06/11/2024] Open
Abstract
Fragile X syndrome (FXS) is characterized by impairments in executive function including different types of learning and memory. Long-term potentiation (LTP), thought to underlie the formation of memories, has been studied in the Fmr1 mouse model of FXS. However, there have been many discrepancies in the literature with inconsistent use of littermate and non-littermate Fmr1 knockout (KO) and wild-type (WT) control mice. Here, the influence of the breeding strategy (cage effect) on short-term potentiation (STP), LTP, contextual fear conditioning (CFC), expression of N-methyl-d-aspartate receptor (NMDAR) subunits and the modulation of NMDARs, were examined. The largest deficits in STP, LTP and CFC were found in KO mice compared with non-littermate WT. However, the expression of NMDAR subunits was unchanged in this comparison. Rather, NMDAR subunit (GluN1, 2A, 2B) expression was sensitive to the cage effect, with decreased expression in both WT and KO littermates compared with non-littermates. Interestingly, an NMDAR-positive allosteric modulator, UBP714, was only effective in potentiating the induction of LTP in non-littermate KO mice and not the littermate KO mice. These results suggest that commonly studied phenotypes in Fmr1 KOs are sensitive to the cage effect and therefore the breeding strategy may contribute to discrepancies in the literature.This article is part of a discussion meeting issue 'Long-term potentiation: 50 years on'.
Collapse
Affiliation(s)
- Rasa Volianskis
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Sinai Health System, Toronto, Ontario M5G 1X5, Canada
- Department of Physiology, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Camilla J Lundbye
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Sinai Health System, Toronto, Ontario M5G 1X5, Canada
- Department of Physiology, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Gillian N Petroff
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Sinai Health System, Toronto, Ontario M5G 1X5, Canada
- Department of Physiology, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - David E Jane
- Hello Bio Limited, Cabot Park, Avonmouth, Bristol BS11 0QL, UK
| | - John Georgiou
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Sinai Health System, Toronto, Ontario M5G 1X5, Canada
- TANZ Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Graham L Collingridge
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Sinai Health System, Toronto, Ontario M5G 1X5, Canada
- Department of Physiology, University of Toronto, Toronto, Ontario M5S 1A8, Canada
- TANZ Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| |
Collapse
|
2
|
Heinze A, Rust MB. Loss of the actin regulator cyclase-associated protein 1 (CAP1) modestly affects dendritic spine remodeling during synaptic plasticity. Eur J Cell Biol 2023; 102:151357. [PMID: 37634312 DOI: 10.1016/j.ejcb.2023.151357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 08/22/2023] [Accepted: 08/24/2023] [Indexed: 08/29/2023] Open
Abstract
Dendritic spines form the postsynaptic compartment of most excitatory synapses in the vertebrate brain. Morphological changes of dendritic spines contribute to major forms of synaptic plasticity such as long-term potentiation (LTP) or depression (LTD). Synaptic plasticity underlies learning and memory, and defects in synaptic plasticity contribute to the pathogeneses of human brain disorders. Hence, deciphering the molecules that drive spine remodeling during synaptic plasticity is critical for understanding the neuronal basis of physiological and pathological brain function. Since actin filaments (F-actin) define dendritic spine morphology, actin-binding proteins (ABP) that accelerate dis-/assembly of F-actin moved into the focus as critical regulators of synaptic plasticity. We recently identified cyclase-associated protein 1 (CAP1) as a novel actin regulator in neurons that cooperates with cofilin1, an ABP relevant for synaptic plasticity. We therefore hypothesized a crucial role for CAP1 in structural synaptic plasticity. By exploiting mouse hippocampal neurons, we tested this hypothesis in the present study. We found that induction of both forms of synaptic plasticity oppositely altered concentration of exogenous, myc-tagged CAP1 in dendritic spines, with chemical LTP (cLTP) decreasing and chemical LTD (cLTD) increasing it. cLTP induced spine enlargement in CAP1-deficient neurons. However, it did not increase the density of large spines, different from control neurons. cLTD induced spine retraction and spine size reduction in control neurons, but not in CAP1-KO neurons. Together, we report that postsynaptic myc-CAP1 concentration oppositely changed during cLTP and cTLD and that CAP1 inactivation modestly affected structural plasticity.
Collapse
Affiliation(s)
- Anika Heinze
- Molecular Neurobiology Group, Institute of Physiological Chemistry, Philipps-University of Marburg, 35032 Marburg, Germany; Center for Mind, Brain and Behavior (CMBB), University of Marburg and Justus-Liebig-University Giessen, 35032 Marburg, Germany
| | - Marco B Rust
- Molecular Neurobiology Group, Institute of Physiological Chemistry, Philipps-University of Marburg, 35032 Marburg, Germany; Center for Mind, Brain and Behavior (CMBB), University of Marburg and Justus-Liebig-University Giessen, 35032 Marburg, Germany.
| |
Collapse
|
3
|
Wang X, Sela-Donenfeld D, Wang Y. Axonal and presynaptic FMRP: Localization, signal, and functional implications. Hear Res 2023; 430:108720. [PMID: 36809742 PMCID: PMC9998378 DOI: 10.1016/j.heares.2023.108720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2022] [Revised: 01/22/2023] [Accepted: 02/09/2023] [Indexed: 02/12/2023]
Abstract
Fragile X mental retardation protein (FMRP) binds a selected set of mRNAs and proteins to guide neural circuit assembly and regulate synaptic plasticity. Loss of FMRP is responsible for Fragile X syndrome, a neuropsychiatric disorder characterized with auditory processing problems and social difficulty. FMRP actions in synaptic formation, maturation, and plasticity are site-specific among the four compartments of a synapse: presynaptic and postsynaptic neurons, astrocytes, and extracellular matrix. This review summarizes advancements in understanding FMRP localization, signals, and functional roles in axons and presynaptic terminals.
Collapse
Affiliation(s)
- Xiaoyu Wang
- Division of Histology & Embryology, Key Laboratory for Regenerative Medicine of the Ministry of Education, Medical College, Jinan University, Guangzhou 510632, China
| | - Dalit Sela-Donenfeld
- Koret School of Veterinary Medicine, Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot 76100, Israel
| | - Yuan Wang
- Department of Biomedical Sciences, Program in Neuroscience, Florida State University College of Medicine, Tallahassee, FL 32306, USA.
| |
Collapse
|
4
|
Stark M, Levin M, Ulitsky I, Assaraf YG. Folylpolyglutamate synthetase mRNA G-quadruplexes regulate its cell protrusion localization and enhance a cancer cell invasive phenotype upon folate repletion. BMC Biol 2023; 21:13. [PMID: 36721160 PMCID: PMC9889130 DOI: 10.1186/s12915-023-01525-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2022] [Accepted: 01/23/2023] [Indexed: 02/02/2023] Open
Abstract
BACKGROUND Folates are crucial for the biosynthesis of nucleotides and amino acids, essential for cell proliferation and development. Folate deficiency induces DNA damage, developmental defects, and tumorigenicity. The obligatory enzyme folylpolyglutamate synthetase (FPGS) mediates intracellular folate retention via cytosolic and mitochondrial folate polyglutamylation. Our previous paper demonstrated the association of the cytosolic FPGS (cFPGS) with the cytoskeleton and various cell protrusion proteins. Based on these recent findings, the aim of the current study was to investigate the potential role of cFPGS at cell protrusions. RESULTS Here we uncovered a central role for two G-quadruplex (GQ) motifs in the 3'UTR of FPGS mediating the localization of cFPGS mRNA and protein at cell protrusions. Using the MBSV6-loop reporter system and fluorescence microscopy, we demonstrate that following folate deprivation, cFPGS mRNA is retained in the endoplasmic reticulum, whereas upon 15 min of folate repletion, this mRNA is rapidly translocated to cell protrusions in a 3'UTR- and actin-dependent manner. The actin dependency of this folate-induced mRNA translocation is shown by treatment with Latrunculin B and inhibitors of the Ras homolog family member A (RhoA) pathway. Upon folate repletion, the FPGS 3'UTR GQs induce an amoeboid/mesenchymal hybrid cell phenotype during migration and invasion through a collagen gel matrix. Targeted disruption of the 3'UTR GQ motifs by introducing point mutations or masking them by antisense oligonucleotides abrogated cell protrusion targeting of cFPGS mRNA. CONCLUSIONS Collectively, the GQ motifs within the 3'UTR of FPGS regulate its transcript and protein localization at cell protrusions in response to a folate cue, inducing cancer cell invasive phenotype. These novel findings suggest that the 3'UTR GQ motifs of FPGS constitute an attractive druggable target aimed at inhibition of cancer invasion and metastasis.
Collapse
Affiliation(s)
- Michal Stark
- grid.6451.60000000121102151The Fred Wyszkowski Cancer Research Laboratory, Department of Biology, Technion-Israel Institute of Technology, 3200003 Haifa, Israel
| | - May Levin
- grid.6451.60000000121102151The Fred Wyszkowski Cancer Research Laboratory, Department of Biology, Technion-Israel Institute of Technology, 3200003 Haifa, Israel ,grid.507132.2Present address: May Levin, MeMed Diagnostics Ltd, Tirat Carmel, Israel
| | - Igor Ulitsky
- grid.13992.300000 0004 0604 7563Department of Immunology and Regenerative Biology and Department of Molecular Neuroscience, Weizmann Institute of Science, 7610001 Rehovot, Israel
| | - Yehuda G. Assaraf
- grid.6451.60000000121102151The Fred Wyszkowski Cancer Research Laboratory, Department of Biology, Technion-Israel Institute of Technology, 3200003 Haifa, Israel
| |
Collapse
|
5
|
Gale JR, Gedeon JY, Donnelly CJ, Gold MS. Local translation in primary afferents and its contribution to pain. Pain 2022; 163:2302-2314. [PMID: 35438669 PMCID: PMC9579217 DOI: 10.1097/j.pain.0000000000002658] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 04/08/2022] [Indexed: 02/06/2023]
Abstract
ABSTRACT Chronic pain remains a significant problem due to its prevalence, impact, and limited therapeutic options. Progress in addressing chronic pain is dependent on a better understanding of underlying mechanisms. Although the available evidence suggests that changes within the central nervous system contribute to the initiation and maintenance of chronic pain, it also suggests that the primary afferent plays a critical role in all phases of the manifestation of chronic pain in most of those who suffer. Most notable among the changes in primary afferents is an increase in excitability or sensitization. A number of mechanisms have been identified that contribute to primary afferent sensitization with evidence for both increases in pronociceptive signaling molecules, such as voltage-gated sodium channels, and decreases in antinociceptive signaling molecules, such as voltage-dependent or calcium-dependent potassium channels. Furthermore, these changes in signaling molecules seem to reflect changes in gene expression as well as posttranslational processing. A mechanism of sensitization that has received far less attention, however, is the local or axonal translation of these signaling molecules. A growing body of evidence indicates that this process not only is dynamically regulated but also contributes to the initiation and maintenance of chronic pain. Here, we review the biology of local translation in primary afferents and its relevance to pain pathobiology.
Collapse
Affiliation(s)
- Jenna R Gale
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213
| | - Jeremy Y Gedeon
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213
| | | | - Michael S Gold
- Corresponding author: Michael S Gold, PhD, Department of Neurobiology, University of Pittsburgh School of Medicine, 200 Lothrop Street, Pittsburgh, PA 15213, P: 412-383-5367,
| |
Collapse
|
6
|
Heinze A, Schuldt C, Khudayberdiev S, van Bommel B, Hacker D, Schulz TG, Stringhi R, Marcello E, Mikhaylova M, Rust MB. Functional interdependence of the actin regulators CAP1 and cofilin1 in control of dendritic spine morphology. Cell Mol Life Sci 2022; 79:558. [PMID: 36264429 PMCID: PMC9585016 DOI: 10.1007/s00018-022-04593-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Revised: 10/06/2022] [Accepted: 10/07/2022] [Indexed: 12/01/2022]
Abstract
The vast majority of excitatory synapses are formed on small dendritic protrusions termed dendritic spines. Dendritic spines vary in size and density that are crucial determinants of excitatory synaptic transmission. Aberrations in spine morphogenesis can compromise brain function and have been associated with neuropsychiatric disorders. Actin filaments (F-actin) are the major structural component of dendritic spines, and therefore, actin-binding proteins (ABP) that control F-actin dis-/assembly moved into the focus as critical regulators of brain function. Studies of the past decade identified the ABP cofilin1 as a key regulator of spine morphology, synaptic transmission, and behavior, and they emphasized the necessity for a tight control of cofilin1 to ensure proper brain function. Here, we report spine enrichment of cyclase-associated protein 1 (CAP1), a conserved multidomain protein with largely unknown physiological functions. Super-resolution microscopy and live cell imaging of CAP1-deficient hippocampal neurons revealed impaired synaptic F-actin organization and dynamics associated with alterations in spine morphology. Mechanistically, we found that CAP1 cooperates with cofilin1 in spines and that its helical folded domain is relevant for this interaction. Moreover, our data proved functional interdependence of CAP1 and cofilin1 in control of spine morphology. In summary, we identified CAP1 as a novel regulator of the postsynaptic actin cytoskeleton that is essential for synaptic cofilin1 activity.
Collapse
Affiliation(s)
- Anika Heinze
- Molecular Neurobiology Group, Institute of Physiological Chemistry, Philipps-University of Marburg, 35032, Marburg, Germany
- Center for Mind, Brain and Behavior (CMBB), University of Marburg and Justus-Liebig-University Giessen, 35032, Marburg, Germany
| | - Cara Schuldt
- Molecular Neurobiology Group, Institute of Physiological Chemistry, Philipps-University of Marburg, 35032, Marburg, Germany
- Center for Mind, Brain and Behavior (CMBB), University of Marburg and Justus-Liebig-University Giessen, 35032, Marburg, Germany
| | - Sharof Khudayberdiev
- Molecular Neurobiology Group, Institute of Physiological Chemistry, Philipps-University of Marburg, 35032, Marburg, Germany
- Center for Mind, Brain and Behavior (CMBB), University of Marburg and Justus-Liebig-University Giessen, 35032, Marburg, Germany
| | - Bas van Bommel
- AG Optobiology, Institute of Biology, Humboldt-University, 10115, Berlin, Germany
- Institute of Chemistry and Biochemistry, Department of Biology, Chemistry and Pharmacy, Freie Universität Berlin, 14195, Berlin, Germany
| | - Daniela Hacker
- AG Optobiology, Institute of Biology, Humboldt-University, 10115, Berlin, Germany
- Guest Group 'Neuronal Protein Transport', Institute for Molecular Neurogenetics, Center for Molecular Neurobiology (ZMNH), University Medical Center Hamburg-Eppendorf (UKE), 20251, Hamburg, Germany
| | - Toni G Schulz
- Molecular Neurobiology Group, Institute of Physiological Chemistry, Philipps-University of Marburg, 35032, Marburg, Germany
| | - Ramona Stringhi
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, 20133, Milan, Italy
| | - Elena Marcello
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, 20133, Milan, Italy
| | - Marina Mikhaylova
- AG Optobiology, Institute of Biology, Humboldt-University, 10115, Berlin, Germany
- Guest Group 'Neuronal Protein Transport', Institute for Molecular Neurogenetics, Center for Molecular Neurobiology (ZMNH), University Medical Center Hamburg-Eppendorf (UKE), 20251, Hamburg, Germany
| | - Marco B Rust
- Molecular Neurobiology Group, Institute of Physiological Chemistry, Philipps-University of Marburg, 35032, Marburg, Germany.
- Center for Mind, Brain and Behavior (CMBB), University of Marburg and Justus-Liebig-University Giessen, 35032, Marburg, Germany.
- DFG Research Training Group 'Membrane Plasticity in Tissue Development and Remodeling', GRK 2213, Philipps-University of Marburg, 35032, Marburg, Germany.
| |
Collapse
|
7
|
Monday HR, Kharod SC, Yoon YJ, Singer RH, Castillo PE. Presynaptic FMRP and local protein synthesis support structural and functional plasticity of glutamatergic axon terminals. Neuron 2022; 110:2588-2606.e6. [PMID: 35728596 PMCID: PMC9391299 DOI: 10.1016/j.neuron.2022.05.024] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 03/31/2022] [Accepted: 05/26/2022] [Indexed: 10/18/2022]
Abstract
Learning and memory rely on long-lasting, synapse-specific modifications. Although postsynaptic forms of plasticity typically require local protein synthesis, whether and how local protein synthesis contributes to presynaptic changes remain unclear. Here, we examined the mouse hippocampal mossy fiber (MF)-CA3 synapse, which expresses both structural and functional presynaptic plasticity and contains presynaptic fragile X messenger ribonucleoprotein (FMRP), an RNA-binding protein involved in postsynaptic protein-synthesis-dependent plasticity. We report that MF boutons contain ribosomes and synthesize protein locally. The long-term potentiation of MF-CA3 synaptic transmission (MF-LTP) was associated with the translation-dependent enlargement of MF boutons. Remarkably, increasing in vitro or in vivo MF activity enhanced the protein synthesis in MFs. Moreover, the deletion of presynaptic FMRP blocked structural and functional MF-LTP, suggesting that FMRP is a critical regulator of presynaptic MF plasticity. Thus, presynaptic FMRP and protein synthesis dynamically control presynaptic structure and function in the mature mammalian brain.
Collapse
Affiliation(s)
- Hannah R Monday
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, New York, NY 10461, USA.
| | - Shivani C Kharod
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, New York, NY 10461, USA
| | - Young J Yoon
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, New York, NY 10461, USA; Department of Cell Biology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, New York, NY 10461, USA
| | - Robert H Singer
- Department of Cell Biology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, New York, NY 10461, USA
| | - Pablo E Castillo
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, New York, NY 10461, USA; Department of Psychiatry and Behavioral Sciences, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, New York, NY 10461, USA.
| |
Collapse
|
8
|
Toupin A, Benachenhou S, Abolghasemi A, Laroui A, Galarneau L, Fülöp T, Corbin F, Çaku A. Association of lipid rafts cholesterol with clinical profile in fragile X syndrome. Sci Rep 2022; 12:2936. [PMID: 35190617 PMCID: PMC8861159 DOI: 10.1038/s41598-022-07064-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Accepted: 02/10/2022] [Indexed: 11/16/2022] Open
Abstract
Fragile X syndrome (FXS) is the most prevalent monogenic cause of intellectual disability and autism spectrum disorder (ASD). Affected individuals have a high prevalence of hypocholesterolemia, however, the underlying mechanisms and the clinical significance remains unknown. We hypothesized that decrease in the plasma cholesterol levels is associated with an alteration of cholesterol content within the lipid rafts (LRs) which ultimately affects the clinical profile of FXS individuals. The platelets LRs were isolated by ultracentrifugation on sucrose gradient from 27 FXS and 25 healthy controls, followed by measurements of proteins, cholesterol, and gangliosides content. Autistic and adaptive behaviour of affected individuals were respectively assessed by the Social Communication Questionnaire and Adaptive Behavior Assessment System. Our results suggest a decrease in the cholesterol content of LRs in FXS individuals as compared to controls. As opposed to controls, LR cholesterol was significantly associated with plasma total cholesterol (r = 0.47; p = 0.042) in the FXS group. Furthermore, the correlation between LRs cholesterol and the clinical profile showed a significant association with autistic traits (r = - 0.67; p < 0.001) and adaptative behavior (r = 0.70; p < 0.001). These results support the clinical significance of LR cholesterol alterations in FXS. Further studies are warranted to investigate the implication of LRs in FXS pathophysiology and ASD.
Collapse
Affiliation(s)
- Amanda Toupin
- Department of Biochemistry and Functional Genomics, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Sérine Benachenhou
- Department of Biochemistry and Functional Genomics, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Armita Abolghasemi
- Department of Biochemistry and Functional Genomics, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Asma Laroui
- Department of Biochemistry and Functional Genomics, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Luc Galarneau
- Department of Biochemistry and Functional Genomics, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Thamàs Fülöp
- Research Center on Aging, CIUSSS de l'Estrie-CHUS, Sherbrooke, QC, Canada
- Department of Medicine, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - François Corbin
- Department of Biochemistry and Functional Genomics, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Artuela Çaku
- Department of Biochemistry and Functional Genomics, Université de Sherbrooke, Sherbrooke, QC, Canada.
| |
Collapse
|
9
|
Schieweck R, Schöneweiss EC, Harner M, Rieger D, Illig C, Saccà B, Popper B, Kiebler MA. Pumilio2 Promotes Growth of Mature Neurons. Int J Mol Sci 2021; 22:ijms22168998. [PMID: 34445704 PMCID: PMC8396670 DOI: 10.3390/ijms22168998] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 08/13/2021] [Accepted: 08/19/2021] [Indexed: 01/05/2023] Open
Abstract
RNA-binding proteins (RBPs) are essential regulators controlling both the cellular transcriptome and translatome. These processes enable cellular plasticity, an important prerequisite for growth. Cellular growth is a complex, tightly controlled process. Using cancer cells as model, we looked for RBPs displaying strong expression in published transcriptome datasets. Interestingly, we found the Pumilio (Pum) protein family to be highly expressed in all these cells. Moreover, we observed that Pum2 is regulated by basic fibroblast growth factor (bFGF). bFGF selectively enhances protein levels of Pum2 and the eukaryotic initiation factor 4E (eIF4E). Exploiting atomic force microscopy and in vitro pulldown assays, we show that Pum2 selects for eIF4E mRNA binding. Loss of Pum2 reduces eIF4E translation. Accordingly, depletion of Pum2 led to decreased soma size and dendritic branching of mature neurons, which was accompanied by a reduction in essential growth factors. In conclusion, we identify Pum2 as an important growth factor for mature neurons. Consequently, it is tempting to speculate that Pum2 may promote cancer growth.
Collapse
Affiliation(s)
- Rico Schieweck
- Biomedical Center (BMC), Department for Cell Biology & Anatomy, Medical Faculty, Ludwig-Maximilians-University, 82152 München, Germany; (R.S.); (M.H.); (D.R.); (C.I.); (M.A.K.)
| | - Elisa-Charlott Schöneweiss
- Zentrum für Medizinische Biotechnologie (ZMB), University of Duisburg-Essen, 41541 Duisburg, Germany; (E.-C.S.); (B.S.)
| | - Max Harner
- Biomedical Center (BMC), Department for Cell Biology & Anatomy, Medical Faculty, Ludwig-Maximilians-University, 82152 München, Germany; (R.S.); (M.H.); (D.R.); (C.I.); (M.A.K.)
| | - Daniela Rieger
- Biomedical Center (BMC), Department for Cell Biology & Anatomy, Medical Faculty, Ludwig-Maximilians-University, 82152 München, Germany; (R.S.); (M.H.); (D.R.); (C.I.); (M.A.K.)
| | - Christin Illig
- Biomedical Center (BMC), Department for Cell Biology & Anatomy, Medical Faculty, Ludwig-Maximilians-University, 82152 München, Germany; (R.S.); (M.H.); (D.R.); (C.I.); (M.A.K.)
| | - Barbara Saccà
- Zentrum für Medizinische Biotechnologie (ZMB), University of Duisburg-Essen, 41541 Duisburg, Germany; (E.-C.S.); (B.S.)
| | - Bastian Popper
- Biomedical Center (BMC), Department for Cell Biology & Anatomy, Medical Faculty, Ludwig-Maximilians-University, 82152 München, Germany; (R.S.); (M.H.); (D.R.); (C.I.); (M.A.K.)
- Biomedical Center (BMC), Core Facility Animal Models, Ludwig-Maximilians-University, 82152 München, Germany
- Correspondence: ; Tel.: +49-89-2180-71996
| | - Michael A. Kiebler
- Biomedical Center (BMC), Department for Cell Biology & Anatomy, Medical Faculty, Ludwig-Maximilians-University, 82152 München, Germany; (R.S.); (M.H.); (D.R.); (C.I.); (M.A.K.)
| |
Collapse
|
10
|
LIM-Kinases in Synaptic Plasticity, Memory, and Brain Diseases. Cells 2021; 10:cells10082079. [PMID: 34440848 PMCID: PMC8391678 DOI: 10.3390/cells10082079] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 07/30/2021] [Accepted: 08/04/2021] [Indexed: 12/12/2022] Open
Abstract
Learning and memory require structural and functional modifications of synaptic connections, and synaptic deficits are believed to underlie many brain disorders. The LIM-domain-containing protein kinases (LIMK1 and LIMK2) are key regulators of the actin cytoskeleton by affecting the actin-binding protein, cofilin. In addition, LIMK1 is implicated in the regulation of gene expression by interacting with the cAMP-response element-binding protein. Accumulating evidence indicates that LIMKs are critically involved in brain function and dysfunction. In this paper, we will review studies on the roles and underlying mechanisms of LIMKs in the regulation of long-term potentiation (LTP) and depression (LTD), the most extensively studied forms of long-lasting synaptic plasticity widely regarded as cellular mechanisms underlying learning and memory. We will also discuss the involvement of LIMKs in the regulation of the dendritic spine, the structural basis of synaptic plasticity, and memory formation. Finally, we will discuss recent progress on investigations of LIMKs in neurological and mental disorders, including Alzheimer’s, Parkinson’s, Williams–Beuren syndrome, schizophrenia, and autism spectrum disorders.
Collapse
|
11
|
Gamarra M, de la Cruz A, Blanco-Urrejola M, Baleriola J. Local Translation in Nervous System Pathologies. Front Integr Neurosci 2021; 15:689208. [PMID: 34276318 PMCID: PMC8279726 DOI: 10.3389/fnint.2021.689208] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 06/03/2021] [Indexed: 12/13/2022] Open
Abstract
Dendrites and axons can extend dozens to hundreds of centimeters away from the cell body so that a single neuron can sense and respond to thousands of stimuli. Thus, for an accurate function of dendrites and axons the neuronal proteome needs to be asymmetrically distributed within neurons. Protein asymmetry can be achieved by the transport of the protein itself or the transport of the mRNA that is then translated at target sites in neuronal processes. The latter transport mechanism implies local translation of localized mRNAs. The role of local translation in nervous system (NS) development and maintenance is well established, but recently there is growing evidence that this mechanism and its deregulation are also relevant in NS pathologies, including neurodegenerative diseases. For instance, upon pathological signals disease-related proteins can be locally synthesized in dendrites and axons. Locally synthesized proteins can exert their effects at or close to the site of translation, or they can be delivered to distal compartments like the nucleus and induce transcriptional responses that lead to neurodegeneration, nerve regeneration and other cell-wide responses. Relevant key players in the process of local protein synthesis are RNA binding proteins (RBPs), responsible for mRNA transport to neurites. Several neurological and neurodegenerative disorders, including amyotrophic lateral sclerosis or spinal motor atrophy, are characterized by mutations in genes encoding for RBPs and consequently mRNA localization and local translation are impaired. In other diseases changes in the local mRNA repertoire and altered local protein synthesis have been reported. In this review, we will discuss how deregulation of localized translation at different levels can contribute to the development and progression of nervous system pathologies.
Collapse
Affiliation(s)
- María Gamarra
- Laboratory of Local Translation in Neurons and Glia, Achucarro Basque Center for Neuroscience, Leioa, Spain.,Departamento de Neurociencias, Universidad del País Vasco (UPV/EHU), Leioa, Spain
| | - Aida de la Cruz
- Laboratory of Local Translation in Neurons and Glia, Achucarro Basque Center for Neuroscience, Leioa, Spain.,Departamento de Neurociencias, Universidad del País Vasco (UPV/EHU), Leioa, Spain
| | - Maite Blanco-Urrejola
- Laboratory of Local Translation in Neurons and Glia, Achucarro Basque Center for Neuroscience, Leioa, Spain.,Departamento de Neurociencias, Universidad del País Vasco (UPV/EHU), Leioa, Spain.,Departamento de Biología Celular e Histología, Universidad del País Vasco (UPV/EHU), Leioa, Spain
| | - Jimena Baleriola
- Laboratory of Local Translation in Neurons and Glia, Achucarro Basque Center for Neuroscience, Leioa, Spain.,Departamento de Biología Celular e Histología, Universidad del País Vasco (UPV/EHU), Leioa, Spain.,Ikerbasque, Basque Foundation for Science, Bilbao, Spain
| |
Collapse
|
12
|
Lo LHY, Dong R, Lyu Q, Lai KO. The Protein Arginine Methyltransferase PRMT8 and Substrate G3BP1 Control Rac1-PAK1 Signaling and Actin Cytoskeleton for Dendritic Spine Maturation. Cell Rep 2021; 31:107744. [PMID: 32521269 DOI: 10.1016/j.celrep.2020.107744] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Revised: 04/01/2020] [Accepted: 05/18/2020] [Indexed: 01/25/2023] Open
Abstract
Excitatory synapses of neurons are located on dendritic spines. Spine maturation is essential for the stability of synapses and memory consolidation, and overproduction of the immature filopodia is associated with brain disorders. The structure and function of synapses can be modulated by protein post-translational modification (PTM). Arginine methylation is a major PTM that regulates chromatin structure, transcription, and splicing within the nucleus. Here we find that the protein arginine methyltransferase PRMT8 is present at neuronal synapses and its expression is upregulated in the hippocampus when dendritic spine maturation occurs. Depletion of PRMT8 leads to overabundance of filopodia and mis-localization of excitatory synapses. Mechanistically, PRMT8 promotes dendritic spine morphology through methylation of the dendritic RNA-binding protein G3BP1 and suppression of the Rac1-PAK1 signaling pathway to control synaptic actin dynamics. Our findings unravel arginine methylation as a crucial regulatory mechanism for actin cytoskeleton during synapse development.
Collapse
Affiliation(s)
- Louisa Hoi-Ying Lo
- School of Biomedical Sciences, The University of Hong Kong, Hong Kong, China
| | - Rui Dong
- School of Biomedical Sciences, The University of Hong Kong, Hong Kong, China
| | - Quanwei Lyu
- School of Biomedical Sciences, The University of Hong Kong, Hong Kong, China
| | - Kwok-On Lai
- School of Biomedical Sciences, The University of Hong Kong, Hong Kong, China; State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong, China.
| |
Collapse
|
13
|
Bruno JL, Hong DS, Lightbody AA, Hosseini SMH, Hallmayer J, Reiss AL. Glucocorticoid regulation and neuroanatomy in fragile x syndrome. J Psychiatr Res 2021; 134:81-88. [PMID: 33373777 PMCID: PMC8577316 DOI: 10.1016/j.jpsychires.2020.12.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Revised: 10/18/2020] [Accepted: 12/09/2020] [Indexed: 10/22/2022]
Abstract
Fragile X syndrome (FXS) is the leading known inherited cause for intellectual disability. Due to mutations in the FMR1 gene, affected individuals are at risk for serious cognitive and behavioral symptoms and developmental disability. Clinical presentation varies considerably, and investigation of genetic factors not directly related to FMR1 may help better understand variability. The present study examined the BclI polymorphism of the glucocorticoid receptor gene NR3C1 in 43 individuals with FXS (28 females, age 16 to 25). Females with FXS who presented with one or more G alleles demonstrated attenuated symptoms of anxiety/depression (p = 0.038) and externalizing behaviors (p = 0.042) relative to individuals with the C/C allele. In the combined sample (males and females) structural neuroimaging data differentiated individuals with a G allele from those with the C/C genotype (p < 0.001). Key components of anxiety/fear neurocircuitry (amygdala, insula) contributed more (relative to other regions) to the model differentiating groups. These results indicate that GR polymorphisms are associated with an altered pattern of behavioral and brain development in FXS. This information is important for understanding and treating mood disorders and altered brain development among individuals with FXS. With further research, these findings could be informative for understanding anxiety and mood disorders more broadly.
Collapse
Affiliation(s)
- Jennifer L Bruno
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, 94304, USA.
| | - David S Hong
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, 94304, USA
| | - Amy A Lightbody
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, 94304, USA
| | - S M Hadi Hosseini
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, 94304, USA
| | - Joachim Hallmayer
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, 94304, USA
| | - Allan L Reiss
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, 94304, USA; Department of Radiology, Stanford University, Stanford, CA, 94304, USA; Department of Pediatrics, Stanford University, Stanford, CA, 94304, USA.
| |
Collapse
|
14
|
Lu JX, Wang Y, Zhang YJ, Shen MF, Li HY, Yu ZQ, Chen G. Axonal mRNA localization and local translation in neurodegenerative disease. Neural Regen Res 2021; 16:1950-1957. [PMID: 33642365 PMCID: PMC8343310 DOI: 10.4103/1673-5374.308074] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The regulation of mRNA localization and local translation play vital roles in the maintenance of cellular structure and function. Many human neurodegenerative diseases, such as fragile X syndrome, amyotrophic lateral sclerosis, Alzheimer's disease, and spinal muscular atrophy, have been characterized by pathological changes in neuronal axons, including abnormal mRNA translation, the loss of protein expression, or abnormal axon transport. Moreover, the same protein and mRNA molecules have been associated with variable functions in different diseases due to differences in their interaction networks. In this review, we briefly examine fragile X syndrome, amyotrophic lateral sclerosis, Alzheimer's disease, and spinal muscular atrophy, with a focus on disease pathogenesis with regard to local mRNA translation and axon transport, suggesting possible treatment directions.
Collapse
Affiliation(s)
- Jin-Xin Lu
- Department of Neurosurgery & Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu Province, China
| | - Yang Wang
- Department of Neurosurgery & Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu Province; Department of Neurosurgery, The First Affiliated Hospital of University of Science and Technology of China, Hefei, Anhui Province, China
| | - Yi-Jie Zhang
- Department of Neurosurgery & Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu Province, China
| | - Mei-Fen Shen
- Department of Neurosurgery & Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu Province, China
| | - Hai-Ying Li
- Department of Neurosurgery & Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu Province, China
| | - Zheng-Quan Yu
- Department of Neurosurgery & Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu Province, China
| | - Gang Chen
- Department of Neurosurgery & Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu Province, China
| |
Collapse
|
15
|
Ben Zablah Y, Merovitch N, Jia Z. The Role of ADF/Cofilin in Synaptic Physiology and Alzheimer's Disease. Front Cell Dev Biol 2020; 8:594998. [PMID: 33282872 PMCID: PMC7688896 DOI: 10.3389/fcell.2020.594998] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Accepted: 10/23/2020] [Indexed: 12/21/2022] Open
Abstract
Actin-depolymerization factor (ADF)/cofilin, a family of actin-binding proteins, are critical for the regulation of actin reorganization in response to various signals. Accumulating evidence indicates that ADF/cofilin also play important roles in neuronal structure and function, including long-term potentiation and depression. These are the most extensively studied forms of long-lasting synaptic plasticity and are widely regarded as cellular mechanisms underlying learning and memory. ADF/cofilin regulate synaptic function through their effects on dendritic spines and the trafficking of glutamate receptors, the principal mediator of excitatory synaptic transmission in vertebrates. Regulation of ADF/cofilin involves various signaling pathways converging on LIM domain kinases and slingshot phosphatases, which phosphorylate/inactivate and dephosphorylate/activate ADF/cofilin, respectively. Actin-depolymerization factor/cofilin activity is also regulated by other actin-binding proteins, activity-dependent subcellular distribution and protein translation. Abnormalities in ADF/cofilin have been associated with several neurodegenerative disorders such as Alzheimer’s disease. Therefore, investigating the roles of ADF/cofilin in the brain is not only important for understanding the fundamental processes governing neuronal structure and function, but also may provide potential therapeutic strategies to treat brain disorders.
Collapse
Affiliation(s)
- Youssif Ben Zablah
- Program in Neurosciences and Mental Health, The Hospital for Sick Children, Peter Gilgan Centre for Research and Learning, Toronto, ON, Canada.,Department of Physiology, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Neil Merovitch
- Program in Neurosciences and Mental Health, The Hospital for Sick Children, Peter Gilgan Centre for Research and Learning, Toronto, ON, Canada.,Department of Physiology, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Zhengping Jia
- Program in Neurosciences and Mental Health, The Hospital for Sick Children, Peter Gilgan Centre for Research and Learning, Toronto, ON, Canada.,Department of Physiology, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| |
Collapse
|
16
|
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: 47] [Impact Index Per Article: 11.8] [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.
Collapse
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
| |
Collapse
|
17
|
Kulkarni A, Lopez DH, Extavour CG. Shared Cell Biological Functions May Underlie Pleiotropy of Molecular Interactions in the Germ Lines and Nervous Systems of Animals. Front Ecol Evol 2020. [DOI: 10.3389/fevo.2020.00215] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
|
18
|
Takabatake M, Goshima Y, Sasaki Y. Semaphorin-3A Promotes Degradation of Fragile X Mental Retardation Protein in Growth Cones via the Ubiquitin-Proteasome Pathway. Front Neural Circuits 2020; 14:5. [PMID: 32184710 PMCID: PMC7059091 DOI: 10.3389/fncir.2020.00005] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Accepted: 02/07/2020] [Indexed: 01/07/2023] Open
Abstract
Fragile X mental retardation protein (FMRP) is an RNA-binding protein that regulates local translation in dendrites and spines for synaptic plasticity. In axons, FMRP is implicated in axonal extension and axon guidance. We previously demonstrated the involvement of FMRP in growth cone collapse via a translation-dependent response to Semaphorin-3A (Sema3A), a repulsive axon guidance factor. In the case of attractive axon guidance factors, RNA-binding proteins such as zipcode binding protein 1 (ZBP1) accumulate towards the stimulated side of growth cones for local translation. However, it remains unclear how Sema3A effects FMRP localization in growth cones. Here, we show that levels of FMRP in growth cones of hippocampal neurons decreased after Sema3A stimulation. This decrease in FMRP was suppressed by the ubiquitin-activating enzyme E1 enzyme inhibitor PYR-41 and proteasome inhibitor MG132, suggesting that the ubiquitin-proteasome pathway is involved in Sema3A-induced FMRP degradation in growth cones. Moreover, the E1 enzyme or proteasome inhibitor suppressed Sema3A-induced increases in microtubule-associated protein 1B (MAP1B) in growth cones, suggesting that the ubiquitin-proteasome pathway promotes local translation of MAP1B, whose translation is mediated by FMRP. These inhibitors also blocked the Sema3A-induced growth cone collapse. Collectively, our results suggest that Sema3A promotes degradation of FMRP in growth cones through the ubiquitin-proteasome pathway, leading to growth cone collapse via local translation of MAP1B. These findings reveal a new mechanism of axon guidance regulation: degradation of the translational suppressor FMRP via the ubiquitin-proteasome pathway.
Collapse
Affiliation(s)
- Masaru Takabatake
- Functional Structure Biology Laboratory, Department of Medical Life Science, Yokohama City University Graduate School of Medical Life Science, Yokohama, Japan
| | - Yoshio Goshima
- Department of Molecular Pharmacology and Neurobiology, Yokohama City University Graduate School of Medicine, Yokohama, Japan
| | - Yukio Sasaki
- Functional Structure Biology Laboratory, Department of Medical Life Science, Yokohama City University Graduate School of Medical Life Science, Yokohama, Japan
| |
Collapse
|
19
|
Cataloguing and Selection of mRNAs Localized to Dendrites in Neurons and Regulated by RNA-Binding Proteins in RNA Granules. Biomolecules 2020; 10:biom10020167. [PMID: 31978946 PMCID: PMC7072219 DOI: 10.3390/biom10020167] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 01/18/2020] [Accepted: 01/20/2020] [Indexed: 12/15/2022] Open
Abstract
Spatiotemporal translational regulation plays a key role in determining cell fate and function. Specifically, in neurons, local translation in dendrites is essential for synaptic plasticity and long-term memory formation. To achieve local translation, RNA-binding proteins in RNA granules regulate target mRNA stability, localization, and translation. To date, mRNAs localized to dendrites have been identified by comprehensive analyses. In addition, mRNAs associated with and regulated by RNA-binding proteins have been identified using various methods in many studies. However, the results obtained from these numerous studies have not been compiled together. In this review, we have catalogued mRNAs that are localized to dendrites and are associated with and regulated by the RNA-binding proteins fragile X mental retardation protein (FMRP), RNA granule protein 105 (RNG105, also known as Caprin1), Ras-GAP SH3 domain binding protein (G3BP), cytoplasmic polyadenylation element binding protein 1 (CPEB1), and staufen double-stranded RNA binding proteins 1 and 2 (Stau1 and Stau2) in RNA granules. This review provides comprehensive information on dendritic mRNAs, the neuronal functions of mRNA-encoded proteins, the association of dendritic mRNAs with RNA-binding proteins in RNA granules, and the effects of RNA-binding proteins on mRNA regulation. These findings provide insights into the mechanistic basis of protein-synthesis-dependent synaptic plasticity and memory formation and contribute to future efforts to understand the physiological implications of local regulation of dendritic mRNAs in neurons.
Collapse
|
20
|
Doll CA, Yergert KM, Appel BH. The RNA binding protein fragile X mental retardation protein promotes myelin sheath growth. Glia 2019; 68:495-508. [PMID: 31626382 DOI: 10.1002/glia.23731] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Revised: 09/20/2019] [Accepted: 09/22/2019] [Indexed: 12/13/2022]
Abstract
During development, oligodendrocytes in the central nervous system extend a multitude of processes that wrap axons with myelin. The highly polarized oligodendrocytes generate myelin sheaths on many different axons, which are far removed from the cell body. Neurons use RNA binding proteins to transport, stabilize, and locally translate mRNA in distal domains of neurons. Local synthesis of synaptic proteins during neurodevelopment facilitates the rapid structural and functional changes underlying neural plasticity and avoids extensive protein transport. We hypothesize that RNA binding proteins also regulate local mRNA regulation in oligodendrocytes to promote myelin sheath growth. Fragile X mental retardation protein (FMRP), an RNA binding protein that plays essential roles in the growth and maturation of neurons, is also expressed in oligodendrocytes. To determine whether oligodendrocytes require FMRP for myelin sheath development, we examined fmr1-/- mutant zebrafish and drove FMR1 expression specifically in oligodendrocytes. We found oligodendrocytes in fmr1-/- mutants developed myelin sheaths of diminished length, a phenotype that can be autonomously rescued in oligodendrocytes with FMR1 expression. Myelin basic protein (Mbp), an essential myelin protein, was reduced in myelin tracts of fmr1-/- mutants, but loss of FMRP function did not impact the localization of mbpa transcript in myelin. Finally, expression of FMR1-I304N, a missense allele that abrogates FMRP association with ribosomes, failed to rescue fmr1-/- mutant sheath growth and induced short myelin sheaths in oligodendrocytes of wild-type larvae. Taken together, these data suggest that FMRP promotes sheath growth through local regulation of translation.
Collapse
Affiliation(s)
- Caleb A Doll
- Department of Pediatrics, University of Colorado School of Medicine, Aurora, Colorado
| | - Katie M Yergert
- Department of Pediatrics, University of Colorado School of Medicine, Aurora, Colorado
| | - Bruce H Appel
- Department of Pediatrics, University of Colorado School of Medicine, Aurora, Colorado
| |
Collapse
|