1
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Lee JY, Gala DS, Kiourlappou M, Olivares-Abril J, Joha J, Titlow JS, Teodoro RO, Davis I. Murine glial protrusion transcripts predict localized Drosophila glial mRNAs involved in plasticity. J Cell Biol 2024; 223:e202306152. [PMID: 39037431 PMCID: PMC11262410 DOI: 10.1083/jcb.202306152] [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: 06/30/2023] [Revised: 06/14/2024] [Accepted: 07/03/2024] [Indexed: 07/23/2024] Open
Abstract
The polarization of cells often involves the transport of specific mRNAs and their localized translation in distal projections. Neurons and glia are both known to contain long cytoplasmic processes, while localized transcripts have only been studied extensively in neurons, not glia, especially in intact nervous systems. Here, we predict 1,740 localized Drosophila glial transcripts by extrapolating from our meta-analysis of seven existing studies characterizing the localized transcriptomes and translatomes of synaptically associated mammalian glia. We demonstrate that the localization of mRNAs in mammalian glial projections strongly predicts the localization of their high-confidence Drosophila homologs in larval motor neuron-associated glial projections and are highly statistically enriched for genes associated with neurological diseases. We further show that some of these localized glial transcripts are specifically required in glia for structural plasticity at the nearby neuromuscular junction synapses. We conclude that peripheral glial mRNA localization is a common and conserved phenomenon and propose that it is likely to be functionally important in disease.
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Affiliation(s)
- Jeffrey Y. Lee
- School of Molecular Biosciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
- Department of Biochemistry, University of Oxford, Oxford, UK
| | - Dalia S. Gala
- Department of Biochemistry, University of Oxford, Oxford, UK
| | | | | | - Jana Joha
- Department of Biochemistry, University of Oxford, Oxford, UK
| | | | - Rita O. Teodoro
- iNOVA4Health, NOVA Medical School | Faculdade de Ciências Médicas, Universidade Nova de Lisboa, Lisboa, Portugal
| | - Ilan Davis
- School of Molecular Biosciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
- Department of Biochemistry, University of Oxford, Oxford, UK
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2
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Rangel-Gomez M, Alberini CM, Deneen B, Drummond GT, Manninen T, Sur M, Vicentic A. Neuron-Glial Interactions: Implications for Plasticity, Behavior, and Cognition. J Neurosci 2024; 44:e1231242024. [PMID: 39358030 PMCID: PMC11450529 DOI: 10.1523/jneurosci.1231-24.2024] [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: 06/29/2024] [Revised: 07/28/2024] [Accepted: 07/29/2024] [Indexed: 10/04/2024] Open
Abstract
The traditional view of glial cells as mere supportive tissue has shifted, due to advances in technology and theoretical conceptualization, to include a diversity of other functions, such as regulation of complex behaviors. Astrocytes, the most abundant glial cells in the central nervous system (CNS), have been shown to modulate synaptic functions through gliotransmitter-mediated neurotransmitter reuptake, influencing neuronal signaling and behavioral functions. Contemporary studies further highlight astrocytes' involvement in complex cognitive functions. For instance, inhibiting astrocytes in the hippocampus can lead to memory deficits, suggesting their integral role in memory processes. Moreover, astrocytic calcium activity and astrocyte-neuron metabolic coupling have been linked to changes in synaptic strength and learning. Microglia, another type of glial cell, also extend beyond their supportive roles, contributing to learning and memory processes, with microglial reductions impacting these functions in a developmentally dependent manner. Oligodendrocytes, traditionally thought to have limited roles postdevelopment, are now recognized for their activity-dependent modulation of myelination and plasticity, thus influencing behavioral responses. Recent advancements in technology and computational modeling have expanded our understanding of glial functions, particularly how astrocytes influence neuronal circuits and behaviors. This review underscores the importance of glial cells in CNS functions and the need for further research to unravel the complexities of neuron-glia interactions, the impact of these interactions on brain functions, and potential implications for neurological diseases.
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Affiliation(s)
- Mauricio Rangel-Gomez
- Division of Neuroscience and Basic Behavioral Sciences, National Institute of Mental Health, Bethesda, Maryland 20852
| | | | - Benjamin Deneen
- Center for Cell and Gene Therapy, Center for Cancer Neuroscience, and Department of Neurosurgery, Baylor College of Medicine, Houston, Texas 77030
| | - Gabrielle T Drummond
- Department of Brain and Cognitive Sciences, Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139
| | - Tiina Manninen
- Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland 33720
| | - Mriganka Sur
- Department of Brain and Cognitive Sciences, Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139
| | - Aleksandra Vicentic
- Division of Neuroscience and Basic Behavioral Sciences, National Institute of Mental Health, Bethesda, Maryland 20852
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3
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Xu J, Hörner M, Nagel M, Perhat P, Korneck M, Noß M, Hauser S, Schöls L, Admard J, Casadei N, Schüle R. Unraveling Axonal Transcriptional Landscapes: Insights from iPSC-Derived Cortical Neurons and Implications for Motor Neuron Degeneration. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.26.586780. [PMID: 38585749 PMCID: PMC10996649 DOI: 10.1101/2024.03.26.586780] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/09/2024]
Abstract
Neuronal function and pathology are deeply influenced by the distinct molecular profiles of the axon and soma. Traditional studies have often overlooked these differences due to the technical challenges of compartment specific analysis. In this study, we employ a robust RNA-sequencing (RNA-seq) approach, using microfluidic devices, to generate high-quality axonal transcriptomes from iPSC-derived cortical neurons (CNs). We achieve high specificity of axonal fractions, ensuring sample purity without contamination. Comparative analysis revealed a unique and specific transcriptional landscape in axonal compartments, characterized by diverse transcript types, including protein-coding mRNAs, RNAs encoding ribosomal proteins (RPs), mitochondrial-encoded RNAs, and long non-coding RNAs (lncRNAs). Previous works have reported the existence of transcription factors (TFs) in the axon. Here, we detect a set of TFs specific to the axon and indicative of their active participation in transcriptional regulation. To investigate transcripts and pathways essential for central motor neuron (MN) degeneration and maintenance we analyzed KIF1C-knockout (KO) CNs, modeling hereditary spastic paraplegia (HSP), a disorder associated with prominent length-dependent degeneration of central MN axons. We found that several key factors crucial for survival and health were absent in KIF1C-KO axons, highlighting a possible role of these also in other neurodegenerative diseases. Taken together, this study underscores the utility of microfluidic devices in studying compartment-specific transcriptomics in human neuronal models and reveals complex molecular dynamics of axonal biology. The impact of KIF1C on the axonal transcriptome not only deepens our understanding of MN diseases but also presents a promising avenue for exploration of compartment specific disease mechanisms.
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4
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Welle TM, Rajgor D, Kareemo DJ, Garcia JD, Zych SM, Wolfe SE, Gookin SE, Martinez TP, Dell'Acqua ML, Ford CP, Kennedy MJ, Smith KR. miRNA-mediated control of gephyrin synthesis drives sustained inhibitory synaptic plasticity. EMBO Rep 2024:10.1038/s44319-024-00253-z. [PMID: 39294503 DOI: 10.1038/s44319-024-00253-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 08/22/2024] [Accepted: 09/02/2024] [Indexed: 09/20/2024] Open
Abstract
Activity-dependent protein synthesis is crucial for long-lasting forms of synaptic plasticity. However, our understanding of translational mechanisms controlling GABAergic synapses is limited. One distinct form of inhibitory long-term potentiation (iLTP) enhances postsynaptic clusters of GABAARs and the primary inhibitory scaffold, gephyrin, to promote sustained synaptic strengthening. While we previously found that persistent iLTP requires mRNA translation, the mechanisms controlling plasticity-induced gephyrin translation remain unknown. We identify miR153 as a novel regulator of Gphn mRNA translation which controls gephyrin protein levels and synaptic clustering, ultimately impacting inhibitory synaptic structure and function. iLTP induction downregulates miR153, reversing its translational suppression of Gphn mRNA and promoting de novo gephyrin protein synthesis and synaptic clustering during iLTP. Finally, we find that reduced miR153 expression during iLTP is driven by an excitation-transcription coupling pathway involving calcineurin, NFAT and HDACs, which also controls the miRNA-dependent upregulation of GABAARs. Together, we delineate a miRNA-dependent post-transcriptional mechanism that controls the expression of the key synaptic scaffold, gephyrin, and may converge with parallel miRNA pathways to coordinate gene upregulation to maintain inhibitory synaptic plasticity.
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Affiliation(s)
- Theresa M Welle
- Department of Pharmacology, University of Colorado School of Medicine, Anschutz Medical Campus, 12800 East 19th Avenue, Aurora, CO, 80045, USA
| | - Dipen Rajgor
- Department of Pharmacology, University of Colorado School of Medicine, Anschutz Medical Campus, 12800 East 19th Avenue, Aurora, CO, 80045, USA
| | - Dean J Kareemo
- Department of Pharmacology, University of Colorado School of Medicine, Anschutz Medical Campus, 12800 East 19th Avenue, Aurora, CO, 80045, USA
| | - Joshua D Garcia
- Department of Pharmacology, University of Colorado School of Medicine, Anschutz Medical Campus, 12800 East 19th Avenue, Aurora, CO, 80045, USA
| | - Sarah M Zych
- Department of Pharmacology, University of Colorado School of Medicine, Anschutz Medical Campus, 12800 East 19th Avenue, Aurora, CO, 80045, USA
| | - Sarah E Wolfe
- Department of Pharmacology, University of Colorado School of Medicine, Anschutz Medical Campus, 12800 East 19th Avenue, Aurora, CO, 80045, USA
| | - Sara E Gookin
- Department of Pharmacology, University of Colorado School of Medicine, Anschutz Medical Campus, 12800 East 19th Avenue, Aurora, CO, 80045, USA
| | - Tyler P Martinez
- Department of Pharmacology, University of Colorado School of Medicine, Anschutz Medical Campus, 12800 East 19th Avenue, Aurora, CO, 80045, USA
| | - Mark L Dell'Acqua
- Department of Pharmacology, University of Colorado School of Medicine, Anschutz Medical Campus, 12800 East 19th Avenue, Aurora, CO, 80045, USA
| | - Christopher P Ford
- Department of Pharmacology, University of Colorado School of Medicine, Anschutz Medical Campus, 12800 East 19th Avenue, Aurora, CO, 80045, USA
| | - Matthew J Kennedy
- Department of Pharmacology, University of Colorado School of Medicine, Anschutz Medical Campus, 12800 East 19th Avenue, Aurora, CO, 80045, USA
| | - Katharine R Smith
- Department of Pharmacology, University of Colorado School of Medicine, Anschutz Medical Campus, 12800 East 19th Avenue, Aurora, CO, 80045, USA.
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5
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Kim S, Phan S, Tran HT, Shaw TR, Shahmoradian SH, Ellisman MH, Veatch SL, Barmada SJ, Pappas SS, Dauer WT. TorsinA is essential for neuronal nuclear pore complex localization and maturation. Nat Cell Biol 2024; 26:1482-1495. [PMID: 39117796 DOI: 10.1038/s41556-024-01480-1] [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: 04/15/2023] [Accepted: 07/11/2024] [Indexed: 08/10/2024]
Abstract
As lifelong interphase cells, neurons face an array of unique challenges. A key challenge is regulating nuclear pore complex (NPC) biogenesis and localization, the mechanisms of which are largely unknown. Here we identify neuronal maturation as a period of strongly upregulated NPC biogenesis. We demonstrate that the AAA+ protein torsinA, whose dysfunction causes the neurodevelopmental movement disorder DYT-TOR1A dystonia and co-ordinates NPC spatial organization without impacting total NPC density. We generated an endogenous Nup107-HaloTag mouse line to directly visualize NPC organization in developing neurons and find that torsinA is essential for proper NPC localization. In the absence of torsinA, the inner nuclear membrane buds excessively at sites of mislocalized nascent NPCs, and the formation of complete NPCs is delayed. Our work demonstrates that NPC spatial organization and number are independently determined and identifies NPC biogenesis as a process vulnerable to neurodevelopmental disease insults.
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Affiliation(s)
- Sumin Kim
- Cellular and Molecular Biology Graduate Program, University of Michigan, Ann Arbor, MI, USA
- Department of Neurology, University of Michigan, Ann Arbor, MI, USA
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Sébastien Phan
- National Center for Microscopy and Imaging Research, Center for Research on Biological Systems, Department of Neurosciences, School of Medicine, University of California San Diego, La Jolla, CA, USA
| | - Hung Tri Tran
- Peter O'Donnell Jr. Brain Institute, UT Southwestern, Dallas, TX, USA
- Center for Alzheimer's and Neurodegenerative Diseases, UT Southwestern, Dallas, TX, USA
| | - Thomas R Shaw
- Department of Biophysics, University of Michigan, Ann Arbor, MI, USA
- Program in Applied Biophysics, University of Michigan, Ann Arbor, MI, USA
| | - Sarah H Shahmoradian
- Peter O'Donnell Jr. Brain Institute, UT Southwestern, Dallas, TX, USA
- Center for Alzheimer's and Neurodegenerative Diseases, UT Southwestern, Dallas, TX, USA
- Department of Biophysics, UT Southwestern, Dallas, TX, USA
| | - Mark H Ellisman
- National Center for Microscopy and Imaging Research, Center for Research on Biological Systems, Department of Neurosciences, School of Medicine, University of California San Diego, La Jolla, CA, USA
| | - Sarah L Veatch
- Department of Biophysics, University of Michigan, Ann Arbor, MI, USA
- Program in Applied Biophysics, University of Michigan, Ann Arbor, MI, USA
| | - Sami J Barmada
- Cellular and Molecular Biology Graduate Program, University of Michigan, Ann Arbor, MI, USA.
- Department of Neurology, University of Michigan, Ann Arbor, MI, USA.
| | - Samuel S Pappas
- Peter O'Donnell Jr. Brain Institute, UT Southwestern, Dallas, TX, USA.
- Department of Neurology, UT Southwestern, Dallas, TX, USA.
| | - William T Dauer
- Peter O'Donnell Jr. Brain Institute, UT Southwestern, Dallas, TX, USA.
- Department of Neurology, UT Southwestern, Dallas, TX, USA.
- Department of Neuroscience, UT Southwestern, Dallas, TX, USA.
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6
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Yaeger CE, Vardalaki D, Zhang Q, Pham TLD, Brown NJ, Ji N, Harnett MT. A dendritic mechanism for balancing synaptic flexibility and stability. Cell Rep 2024; 43:114638. [PMID: 39167486 PMCID: PMC11403626 DOI: 10.1016/j.celrep.2024.114638] [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: 04/16/2024] [Revised: 06/28/2024] [Accepted: 07/30/2024] [Indexed: 08/23/2024] Open
Abstract
Biological and artificial neural networks learn by modifying synaptic weights, but it is unclear how these systems retain previous knowledge and also acquire new information. Here, we show that cortical pyramidal neurons can solve this plasticity-versus-stability dilemma by differentially regulating synaptic plasticity at distinct dendritic compartments. Oblique dendrites of adult mouse layer 5 cortical pyramidal neurons selectively receive monosynaptic thalamic input, integrate linearly, and lack burst-timing synaptic potentiation. In contrast, basal dendrites, which do not receive thalamic input, exhibit conventional NMDA receptor (NMDAR)-mediated supralinear integration and synaptic potentiation. Congruently, spiny synapses on oblique branches show decreased structural plasticity in vivo. The selective decline in NMDAR activity and expression at synapses on oblique dendrites is controlled by a critical period of visual experience. Our results demonstrate a biological mechanism for how single neurons can safeguard a set of inputs from ongoing plasticity by altering synaptic properties at distinct dendritic domains.
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Affiliation(s)
- Courtney E Yaeger
- McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Dimitra Vardalaki
- McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Qinrong Zhang
- Department of Physics, University of California, Berkeley, Berkeley, CA 94720, USA; Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Trang L D Pham
- McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Norma J Brown
- McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Na Ji
- Department of Physics, University of California, Berkeley, Berkeley, CA 94720, USA; Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA; Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA 94720, USA; Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Mark T Harnett
- McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
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7
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Wang L, Li P. Arginine methylation-enabled FUS phase separation with SMN contributes to neuronal granule formation. Cell Rep 2024; 43:114537. [PMID: 39052476 DOI: 10.1016/j.celrep.2024.114537] [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: 09/11/2023] [Revised: 05/03/2024] [Accepted: 07/09/2024] [Indexed: 07/27/2024] Open
Abstract
Various ribonucleoprotein complexes (RNPs) often function in the form of membraneless organelles derived from multivalence-driven liquid-liquid phase separation (LLPS). Post-translational modifications, such as phosphorylation and arginine methylation, govern the assembly and disassembly of membraneless organelles. This study reveals that asymmetric dimethylation of arginine can create extra binding sites for multivalent Tudor domain-containing proteins like survival of motor neuron (SMN) protein, thereby lowering the threshold for LLPS of RNPs, such as fused in sarcoma (FUS). Accordingly, FUS hypomethylation or knockdown of SMN disrupts the formation and transport of neuronal granules in axons. Wild-type SMN, but not the spinal muscular atrophy-associated form of SMN, SMN-Δ7, rescues neuronal defects due to SMN knockdown. Importantly, a fusion of SMN-Δ7 to an exogenous oligomeric protein is sufficient to rescue axon length defects caused by SMN knockdown. Our findings highlight the significant role of arginine methylation-enabled multivalent interactions in LLPS and suggest their potential impact on various aspects of neuronal activities in neurodegenerative diseases.
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Affiliation(s)
- Lingyao Wang
- State Key Laboratory of Membrane Biology, Beijing Frontier Research Center for Biological Structure, School of Life Sciences, Tsinghua University; Tsinghua-Peking Center for Life Sciences, Beijing 100084, China
| | - Pilong Li
- State Key Laboratory of Membrane Biology, Beijing Frontier Research Center for Biological Structure, School of Life Sciences, Tsinghua University; Tsinghua-Peking Center for Life Sciences, Beijing 100084, China.
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8
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Scott-Hewitt N, Mahoney M, Huang Y, Korte N, Yvanka de Soysa T, Wilton DK, Knorr E, Mastro K, Chang A, Zhang A, Melville D, Schenone M, Hartigan C, Stevens B. Microglial-derived C1q integrates into neuronal ribonucleoprotein complexes and impacts protein homeostasis in the aging brain. Cell 2024; 187:4193-4212.e24. [PMID: 38942014 DOI: 10.1016/j.cell.2024.05.058] [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: 05/31/2023] [Revised: 01/08/2024] [Accepted: 05/31/2024] [Indexed: 06/30/2024]
Abstract
Neuroimmune interactions mediate intercellular communication and underlie critical brain functions. Microglia, CNS-resident macrophages, modulate the brain through direct physical interactions and the secretion of molecules. One such secreted factor, the complement protein C1q, contributes to complement-mediated synapse elimination in both developmental and disease models, yet brain C1q protein levels increase significantly throughout aging. Here, we report that C1q interacts with neuronal ribonucleoprotein (RNP) complexes in an age-dependent manner. Purified C1q protein undergoes RNA-dependent liquid-liquid phase separation (LLPS) in vitro, and the interaction of C1q with neuronal RNP complexes in vivo is dependent on RNA and endocytosis. Mice lacking C1q have age-specific alterations in neuronal protein synthesis in vivo and impaired fear memory extinction. Together, our findings reveal a biophysical property of C1q that underlies RNA- and age-dependent neuronal interactions and demonstrate a role of C1q in critical intracellular neuronal processes.
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Affiliation(s)
- Nicole Scott-Hewitt
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA 02115, USA; The Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.
| | - Matthew Mahoney
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA 02115, USA
| | - Youtong Huang
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA 02115, USA; The Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Nils Korte
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA 02115, USA; The Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - T Yvanka de Soysa
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA 02115, USA; The Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Daniel K Wilton
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA 02115, USA; The Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Emily Knorr
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA 02115, USA
| | - Kevin Mastro
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA 02115, USA; The Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Allison Chang
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA 02115, USA
| | - Allison Zhang
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA 02115, USA
| | - David Melville
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA 02115, USA
| | - Monica Schenone
- The Broad Proteomics Platform, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Christina Hartigan
- The Broad Proteomics Platform, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Beth Stevens
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA 02115, USA; The Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Howard Hughes Medical Investigator, Boston Children's Hospital, Boston, MA 02115, USA.
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9
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Parkins EV, Gross C. Small Differences and Big Changes: The Many Variables of MicroRNA Expression and Function in the Brain. J Neurosci 2024; 44:e0365242024. [PMID: 39111834 PMCID: PMC11308354 DOI: 10.1523/jneurosci.0365-24.2024] [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: 02/24/2024] [Revised: 05/15/2024] [Accepted: 05/23/2024] [Indexed: 08/10/2024] Open
Abstract
MicroRNAs are emerging as crucial regulators within the complex, dynamic environment of the synapse, and they offer a promising new avenue for the treatment of neurological disease. These small noncoding RNAs modify gene expression in several ways, including posttranscriptional modulation via binding to complementary and semicomplementary sites on target mRNAs. This rapid, finely tuned regulation of gene expression is essential to meet the dynamic demands of the synapse. Here, we provide a detailed review of the multifaceted world of synaptic microRNA regulation. We discuss the many mechanisms by which microRNAs regulate gene expression at the synapse, particularly in the context of neuronal plasticity. We also describe the various factors, such as age, sex, and neurological disease, that can influence microRNA expression and activity in neurons. In summary, microRNAs play a crucial role in the intricate and quickly changing functional requirements of the synapse, and context is essential in the study of microRNAs and their potential therapeutic applications.
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Affiliation(s)
- Emma V Parkins
- University of Cincinnati Neuroscience Graduate Program, Cincinnati, Ohio 45229
- Division of Neurology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio 45229
| | - Christina Gross
- University of Cincinnati Neuroscience Graduate Program, Cincinnati, Ohio 45229
- Division of Neurology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio 45229
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio 45229
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10
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Dong X, Wang Y, Liu Y, Li Y. Fear generalization modulated by shock intensity and protein synthesis inhibitor. Psychopharmacology (Berl) 2024:10.1007/s00213-024-06662-1. [PMID: 39105767 DOI: 10.1007/s00213-024-06662-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2024] [Accepted: 07/29/2024] [Indexed: 08/07/2024]
Abstract
RATIONALE Maladaptive fear responses, including sensitized threat reactions and overgeneralization, contribute to anxiety disorders such as generalized anxiety disorder and post-traumatic stress disorder. Although stress intensity influences the generation and extent of these maladaptive fears, the underlying mechanisms remain unclear. OBJECTIVES The present study examined whether varying footshock stress intensity and inhibition of protein synthesis have differential effect on fear sensitization and generalization in mice. METHODS Mice were subjected to a classic fear conditioning protocol involving five different levels of footshock intensities. Prior to fear acquisition, the protein synthesis inhibitor cycloheximide (CHX) was administered intraperitoneally. Fear sensitization to white noise and fear generalization to tones with frequencies differing from the conditioned tone were assessed at either 2 or 4 days after fear acquisition. RESULTS The results showed that, although varying shock intensities (except the lowest) led to a similar pattern of increased freezing during auditory cues in fear acquisition, the extent of both fear sensitization and generalization increased with the intensity of the footshock in the following days. As shock intensities increased, there was a proportional rise in sensitized fear to white noise and generalized freezing to tones with frequencies progressively closer to the conditioned stimulus. Mildest shocks did not induce discriminative conditioned fear memory, whereas the most intense shocks led to pronounced fear generalization. Administration of CHX before fear acquisition did not affect sensitized fear but reduced generalization of freezing to tones dissimilar from the conditioned stimulus in the group exposed to the most intense shock. CONCLUSIONS Our results suggest that maladaptive fear responses elicited by varying stress intensities exhibit distinct characteristics. The effect of CHX to prevent overgeneralization without affecting discriminative fear memory points to potential therapeutic approaches for fear-related disorders, suggesting the possibility of mitigating overgeneralization while preserving necessary fear discrimination.
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Affiliation(s)
- Xinwen Dong
- Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing, China.
| | - Yunyun Wang
- Department of Neuroendocrine Pharmacology, School of Pharmacy, China Medical University, Shenyang, China
| | - Yudan Liu
- Department of Neuroendocrine Pharmacology, School of Pharmacy, China Medical University, Shenyang, China
| | - Yonghui Li
- Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing, China
- Department of Psychology, University of Chinese Academy of Sciences, Beijing, China
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11
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Moreira-Gomes T, Nóbrega C. From the disruption of RNA metabolism to the targeting of RNA-binding proteins: The case of polyglutamine spinocerebellar ataxias. J Neurochem 2024; 168:1442-1459. [PMID: 37990934 DOI: 10.1111/jnc.16010] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 10/04/2023] [Accepted: 11/03/2023] [Indexed: 11/23/2023]
Abstract
Polyglutamine spinocerebellar ataxias (PolyQ SCAs) represent a group of monogenetic diseases in which the expanded polyglutamine repeats give rise to a mutated protein. The abnormally expanded polyglutamine protein produces aggregates and toxic species, causing neuronal dysfunction and neuronal death. The main symptoms of these disorders include progressive ataxia, motor dysfunction, oculomotor impairment, and swallowing problems. Nowadays, the current treatments are restricted to symptomatic alleviation, and no existing therapeutic strategies can reduce or stop the disease progression. Even though the origin of these disorders has been associated with polyglutamine-induced toxicity, RNA toxicity has recently gained relevance in polyQ SCAs molecular pathogenesis. Therefore, the research's focus on RNA metabolism has been increasing, especially on RNA-binding proteins (RBPs). The present review summarizes RNA metabolism, exposing the different processes and the main RBPs involved. We also explore the mechanisms by which RBPs are dysregulated in PolyQ SCAs. Finally, possible therapies targeting the RNA metabolism are presented as strategies to reverse neuropathological anomalies and mitigate physical symptoms.
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Affiliation(s)
- Tiago Moreira-Gomes
- ABC-RI, Algarve Biomedical Center Research Institute, Faro, Portugal
- Faculdade de Medicina e Ciências Biomédicas, Universidade do Algarve, Faro, Portugal
- Doctoral Program in Biomedical Sciences, Faculdade de Medicina e Ciências Biomédicas, Universidade do Algarve, Faro, Portugal
| | - Clévio Nóbrega
- ABC-RI, Algarve Biomedical Center Research Institute, Faro, Portugal
- Faculdade de Medicina e Ciências Biomédicas, Universidade do Algarve, Faro, Portugal
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12
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Ramakrishna S, Radhakrishna BK, Kaladiyil AP, Shah NM, Basavaraju N, Freude KK, Kommaddi RP, Muddashetty RS. Distinct calcium sources regulate temporal profiles of NMDAR and mGluR-mediated protein synthesis. Life Sci Alliance 2024; 7:e202402594. [PMID: 38749544 PMCID: PMC11096670 DOI: 10.26508/lsa.202402594] [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: 01/14/2024] [Revised: 05/02/2024] [Accepted: 05/02/2024] [Indexed: 05/18/2024] Open
Abstract
Calcium signaling is integral for neuronal activity and synaptic plasticity. We demonstrate that the calcium response generated by different sources modulates neuronal activity-mediated protein synthesis, another process essential for synaptic plasticity. Stimulation of NMDARs generates a protein synthesis response involving three phases-increased translation inhibition, followed by a decrease in translation inhibition, and increased translation activation. We show that these phases are linked to NMDAR-mediated calcium response. Calcium influx through NMDARs elicits increased translation inhibition, which is necessary for the successive phases. Calcium through L-VGCCs acts as a switch from translation inhibition to the activation phase. NMDAR-mediated translation activation requires the contribution of L-VGCCs, RyRs, and SOCE. Furthermore, we show that IP3-mediated calcium release and SOCE are essential for mGluR-mediated translation up-regulation. Finally, we signify the relevance of our findings in the context of Alzheimer's disease. Using neurons derived from human fAD iPSCs and transgenic AD mice, we demonstrate the dysregulation of NMDAR-mediated calcium and translation response. Our study highlights the complex interplay between calcium signaling and protein synthesis, and its implications in neurodegeneration.
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Affiliation(s)
- Sarayu Ramakrishna
- https://ror.org/04dese585 Centre for Brain Research, Indian Institute of Science, Bangalore, India
| | - Bindushree K Radhakrishna
- https://ror.org/04dese585 Centre for Brain Research, Indian Institute of Science, Bangalore, India
- Manipal Academy of Higher Education, Manipal, India
| | - Ahamed P Kaladiyil
- https://ror.org/04dese585 Centre for Brain Research, Indian Institute of Science, Bangalore, India
| | - Nisa Manzoor Shah
- https://ror.org/04dese585 Centre for Brain Research, Indian Institute of Science, Bangalore, India
- Manipal Academy of Higher Education, Manipal, India
| | - Nimisha Basavaraju
- https://ror.org/04dese585 Centre for Brain Research, Indian Institute of Science, Bangalore, India
- Manipal Academy of Higher Education, Manipal, India
| | - Kristine K Freude
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg C, Denmark
| | - Reddy Peera Kommaddi
- https://ror.org/04dese585 Centre for Brain Research, Indian Institute of Science, Bangalore, India
| | - Ravi S Muddashetty
- https://ror.org/04dese585 Centre for Brain Research, Indian Institute of Science, Bangalore, India
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13
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Lockshin ER, Calakos N. The integrated stress response in brain diseases: A double-edged sword for proteostasis and synapses. Curr Opin Neurobiol 2024; 87:102886. [PMID: 38901329 DOI: 10.1016/j.conb.2024.102886] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2024] [Revised: 05/22/2024] [Accepted: 05/24/2024] [Indexed: 06/22/2024]
Abstract
The integrated stress response (ISR) is a highly conserved biochemical pathway that regulates protein synthesis. The ISR is activated in response to diverse stressors to restore cellular homeostasis. As such, the ISR is implicated in a wide range of diseases, including brain disorders. However, in the brain, the ISR also has potent influence on processes beyond proteostasis, namely synaptic plasticity, learning and memory. Thus, in the setting of brain diseases, ISR activity may have dual effects on proteostasis and synaptic function. In this review, we consider the ISR's contribution to brain disorders through the lens of its potential effects on synaptic plasticity. From these examples, we illustrate that at times ISR activity may be a "double-edged sword". We also highlight its potential as a therapeutic target to improve circuit function in brain diseases independent of its role in disease pathogenesis.
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Affiliation(s)
- Elana R Lockshin
- Department of Neurobiology, Duke University Medical Center, Durham, NC 27710, USA; Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, USA
| | - Nicole Calakos
- Department of Neurobiology, Duke University Medical Center, Durham, NC 27710, USA; Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, USA; Department of Neurology, Duke University Medical Center, Durham, NC 27710, USA; Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA.
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14
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Wang X, Yang Q, Zhou X, Keene CD, Ryazanov AG, Ma T. Suppression of eEF2 phosphorylation alleviates synaptic failure and cognitive deficits in mouse models of Down syndrome. Alzheimers Dement 2024; 20:5357-5374. [PMID: 38934363 PMCID: PMC11350057 DOI: 10.1002/alz.13916] [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: 01/12/2024] [Revised: 04/11/2024] [Accepted: 05/01/2024] [Indexed: 06/28/2024]
Abstract
INTRODUCTION Cognitive impairment is a core feature of Down syndrome (DS), and the underlying neurobiological mechanisms remain unclear. Translation dysregulation is linked to multiple neurological disorders characterized by cognitive impairments. Phosphorylation of the translational factor eukaryotic elongation factor 2 (eEF2) by its kinase eEF2K results in inhibition of general protein synthesis. METHODS We used genetic and pharmacological methods to suppress eEF2K in two lines of DS mouse models. We further applied multiple approaches to evaluate the effects of eEF2K inhibition on DS pathophysiology. RESULTS We found that eEF2K signaling was overactive in the brain of patients with DS and DS mouse models. Inhibition of eEF2 phosphorylation through suppression of eEF2K in DS model mice improved multiple aspects of DS-associated pathophysiology including de novo protein synthesis deficiency, synaptic morphological defects, long-term synaptic plasticity failure, and cognitive impairments. DISCUSSION Our data suggested that eEF2K signaling dysregulation mediates DS-associated synaptic and cognitive impairments. HIGHLIGHTS Phosphorylation of the translational factor eukaryotic elongation factor 2 (eEF2) is increased in the Down syndrome (DS) brain. Suppression of the eEF2 kinase (eEF2K) alleviates cognitive deficits in DS models. Suppression of eEF2K improves synaptic dysregulation in DS models. Cognitive and synaptic impairments in DS models are rescued by eEF2K inhibitors.
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Affiliation(s)
- Xin Wang
- Department of Internal MedicineGerontology and Geriatric MedicineWake Forest University School of MedicineWinston‐SalemNorth CarolinaUSA
| | - Qian Yang
- Department of Internal MedicineGerontology and Geriatric MedicineWake Forest University School of MedicineWinston‐SalemNorth CarolinaUSA
| | - Xueyan Zhou
- Department of Internal MedicineGerontology and Geriatric MedicineWake Forest University School of MedicineWinston‐SalemNorth CarolinaUSA
| | - C. Dirk Keene
- Department of PathologyUniversity of Washington School of MedicineSeattleWashingtonUSA
| | - Alexey G. Ryazanov
- Department of PharmacologyRutgers Robert Wood Johnson Medical SchoolPiscatawayNew JerseyUSA
| | - Tao Ma
- Department of Internal MedicineGerontology and Geriatric MedicineWake Forest University School of MedicineWinston‐SalemNorth CarolinaUSA
- Department of Translational NeuroscienceWake Forest University School of MedicineWinston‐SalemNorth CarolinaUSA
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Chen Y, Wang H, Chen H, Zhang W, Pätzel M, Han B, Wang K, Xu S, Montes-García V, McCulloch I, Hecht S, Samorì P. Li Promoting Long Afterglow Organic Light-Emitting Transistor for Memory Optocoupler Module. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2402515. [PMID: 38616719 DOI: 10.1002/adma.202402515] [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: 02/18/2024] [Revised: 03/19/2024] [Indexed: 04/16/2024]
Abstract
The artificial brain is conceived as advanced intelligence technology, capable to emulate in-memory processes occurring in the human brain by integrating synaptic devices. Within this context, improving the functionality of synaptic transistors to increase information processing density in neuromorphic chips is a major challenge in this field. In this article, Li-ion migration promoting long afterglow organic light-emitting transistors, which display exceptional postsynaptic brightness of 7000 cd m-2 under low operational voltages of 10 V is presented. The postsynaptic current of 0.1 mA operating as a built-in threshold switch is implemented as a firing point in these devices. The setting-condition-triggered long afterglow is employed to drive the photoisomerization process of photochromic molecules that mimic neurotransmitter transfer in the human brain for realizing a key memory rule, that is, the transition from long-term memory to permanent memory. The combination of setting-condition-triggered long afterglow with photodiode amplifiers is also processed to emulate the human responding action after the setting-training process. Overall, the successful integration in neuromorphic computing comprising stimulus judgment, photon emission, transition, and encoding, to emulate the complicated decision tree of the human brain is demonstrated.
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Affiliation(s)
- Yusheng Chen
- Université de Strasbourg, CNRS, ISIS, 8 allée Gaspard Monge, Strasbourg, 67000, France
| | - Hanlin Wang
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Organic Solids, Institute of Chemistry Chinese Academy of Sciences, Beijing, 100190, P. R. China
| | - Hu Chen
- School of Physical Sciences, Great Bay University, Dongguan, 523000, China
| | - Weimin Zhang
- Physical Sciences and Engineering Division, KAUST Solar Center (KSC), King Abdullah University of Science and Technology (KAUST), KSC, Thuwal, 23955-6900, Saudi Arabia
| | - Michael Pätzel
- Department of Chemistry & Center for the Science of Materials Berlin, Humboldt-Universität zu Berlin, Brook-Taylor-Str. 2, 12489, Berlin, Germany
| | - Bin Han
- Université de Strasbourg, CNRS, ISIS, 8 allée Gaspard Monge, Strasbourg, 67000, France
| | - Kexin Wang
- Université de Strasbourg, CNRS, ISIS, 8 allée Gaspard Monge, Strasbourg, 67000, France
| | - Shunqi Xu
- Université de Strasbourg, CNRS, ISIS, 8 allée Gaspard Monge, Strasbourg, 67000, France
| | | | - Iain McCulloch
- Physical Sciences and Engineering Division, KAUST Solar Center (KSC), King Abdullah University of Science and Technology (KAUST), KSC, Thuwal, 23955-6900, Saudi Arabia
- University of Oxford, Department of Chemistry, Oxford, OX1 3TA, UK
| | - Stefan Hecht
- Department of Chemistry & Center for the Science of Materials Berlin, Humboldt-Universität zu Berlin, Brook-Taylor-Str. 2, 12489, Berlin, Germany
- DWI - Leibniz Institute for Interactive Materials, Forckenbeckstr. 50, 52074, Aachen, Germany
| | - Paolo Samorì
- Université de Strasbourg, CNRS, ISIS, 8 allée Gaspard Monge, Strasbourg, 67000, France
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Badal KK, Sadhu A, Raveendra BL, McCracken C, Lozano-Villada S, Shetty AC, Gillette P, Zhao Y, Stommes D, Fieber LA, Schmale MC, Mahurkar A, Hawkins RD, Puthanveettil SV. Single-neuron analysis of aging-associated changes in learning reveals impairments in transcriptional plasticity. Aging Cell 2024:e14228. [PMID: 38924663 DOI: 10.1111/acel.14228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2024] [Accepted: 05/02/2024] [Indexed: 06/28/2024] Open
Abstract
The molecular mechanisms underlying age-related declines in learning and long-term memory are still not fully understood. To address this gap, our study focused on investigating the transcriptional landscape of a singularly identified motor neuron L7 in Aplysia, which is pivotal in a specific type of nonassociative learning known as sensitization of the siphon-withdraw reflex. Employing total RNAseq analysis on a single isolated L7 motor neuron after short-term or long-term sensitization (LTS) training of Aplysia at 8, 10, and 12 months (representing mature, late mature, and senescent stages), we uncovered aberrant changes in transcriptional plasticity during the aging process. Our findings specifically highlight changes in the expression of messenger RNAs (mRNAs) that encode transcription factors, translation regulators, RNA methylation participants, and contributors to cytoskeletal rearrangements during learning and long noncoding RNAs (lncRNAs). Furthermore, our comparative gene expression analysis identified distinct transcriptional alterations in two other neurons, namely the motor neuron L11 and the giant cholinergic neuron R2, whose roles in LTS are not yet fully elucidated. Taken together, our analyses underscore cell type-specific impairments in the expression of key components related to learning and memory within the transcriptome as organisms age, shedding light on the complex molecular mechanisms driving cognitive decline during aging.
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Affiliation(s)
- Kerriann K Badal
- Department of Neuroscience, The Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, Florida, USA
- Integrated Biology Graduate Program, Florida Atlantic University, Jupiter, Florida, USA
| | - Abhishek Sadhu
- Department of Neuroscience, The Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, Florida, USA
| | - Bindu L Raveendra
- Department of Neuroscience, The Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, Florida, USA
| | - Carrie McCracken
- The Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Sebastian Lozano-Villada
- Department of Neuroscience, The Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, Florida, USA
- Harriet L. Wilkes Honors College, Florida Atlantic University, Jupiter, Florida, USA
| | - Amol C Shetty
- The Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Phillip Gillette
- National Resource for Aplysia, University of Miami Rosenstiel School of Marine, Atmospheric, and Earth Sciences, Miami, Florida, USA
| | - Yibo Zhao
- Department of Neuroscience, The Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, Florida, USA
| | - Dustin Stommes
- National Resource for Aplysia, University of Miami Rosenstiel School of Marine, Atmospheric, and Earth Sciences, Miami, Florida, USA
| | - Lynne A Fieber
- National Resource for Aplysia, University of Miami Rosenstiel School of Marine, Atmospheric, and Earth Sciences, Miami, Florida, USA
| | - Michael C Schmale
- National Resource for Aplysia, University of Miami Rosenstiel School of Marine, Atmospheric, and Earth Sciences, Miami, Florida, USA
| | - Anup Mahurkar
- The Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Robert D Hawkins
- Department of Neuroscience, Columbia University, New York, New York, USA
- New York State Psychiatric Institute, New York, New York, USA
| | - Sathyanarayanan V Puthanveettil
- Department of Neuroscience, The Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, Florida, USA
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17
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Tuna AR, Pinto N, Fernandes A, Brardo FM, Vaz Pato M. Longstanding effects of continuous theta burst stimulation in adult amblyopes. Clin Exp Optom 2024; 107:457-464. [PMID: 37400360 DOI: 10.1080/08164622.2023.2228989] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Revised: 06/02/2023] [Accepted: 06/16/2023] [Indexed: 07/05/2023] Open
Abstract
CLINICAL RELEVANCE Continuous theta burst stimulation may be an important tool in the therapeutic management of amblyopia, when trying to correct the established neuronal imbalance. It is important to understand whether two sessions of continuous theta burst stimulation produce greater and longstanding changes in visual acuity and suppressive imbalance than one session of continuous theta burst stimulation. BACKGROUND We hypothesise that through the usage of continuous theta burst stimulation (cTBS) it is possible to change cortical excitability in a situation where visual impairment is present. METHODS We selected 22 adult amblyopes, 18 females and 4 males, with an age range of 20-59 years. They were randomised into two groups: group A with 10 amblyopes was submitted to one session of cTBS and group B with 12 amblyopes submitted to two sessions of cTBS. Visual acuity (VA) and suppressive imbalance (SI) were evaluated immediately before and after stimulation in both groups A and B. A follow-up was done in both groups. RESULTS For both group A and B, the VA improvements were significant after cTBS (p = 0.005 and p = 0.003, respectively). Regarding SI, both group A and B had significant improvements after cTBS (p = 0.03 and p = 0.005, respectively). Comparing groups, A and B no significant differences were found with regard to the results obtained both for VA (p = 0.72) and SI (p = 0.24). However, significant differences were found between group A and B with regard to the duration of stimulation effect for VA (p = 0.049) and SI (p = 0.03). CONCLUSION We conclude that two sessions of cTBS do not produce better results than one session of stimulation. However, it seems that two sessions of cTBS produce longstanding effects in VA and SI.
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Affiliation(s)
- Ana Rita Tuna
- CICS - Health Sciences Research Centre, Faculty of Health Sciences, University of Beira Interior, Covilhã, Portugal
| | - Nuno Pinto
- CICS - Health Sciences Research Centre, Faculty of Health Sciences, University of Beira Interior, Covilhã, Portugal
| | - Andresa Fernandes
- CICS - Health Sciences Research Centre, Faculty of Health Sciences, University of Beira Interior, Covilhã, Portugal
- Department of Physics, University of Beira Interior, Covilhã, Portugal
| | - Francisco Miguel Brardo
- CICS - Health Sciences Research Centre, Faculty of Health Sciences, University of Beira Interior, Covilhã, Portugal
- Department of Physics, University of Beira Interior, Covilhã, Portugal
| | - Maria Vaz Pato
- CICS - Health Sciences Research Centre, Faculty of Health Sciences, University of Beira Interior, Covilhã, Portugal
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Calakos N, Caffall ZF. The integrated stress response pathway and neuromodulator signaling in the brain: lessons learned from dystonia. J Clin Invest 2024; 134:e177833. [PMID: 38557486 PMCID: PMC10977992 DOI: 10.1172/jci177833] [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] [Indexed: 04/04/2024] Open
Abstract
The integrated stress response (ISR) is a highly conserved biochemical pathway involved in maintaining proteostasis and cell health in the face of diverse stressors. In this Review, we discuss a relatively noncanonical role for the ISR in neuromodulatory neurons and its implications for synaptic plasticity, learning, and memory. Beyond its roles in stress response, the ISR has been extensively studied in the brain, where it potently influences learning and memory, and in the process of synaptic plasticity, which is a substrate for adaptive behavior. Recent findings demonstrate that some neuromodulatory neuron types engage the ISR in an "always-on" mode, rather than the more canonical "on-demand" response to transient perturbations. Atypical demand for the ISR in neuromodulatory neurons introduces an additional mechanism to consider when investigating ISR effects on synaptic plasticity, learning, and memory. This basic science discovery emerged from a consideration of how the ISR might be contributing to human disease. To highlight how, in scientific discovery, the route from starting point to outcomes can often be circuitous and full of surprise, we begin by describing our group's initial introduction to the ISR, which arose from a desire to understand causes for a rare movement disorder, dystonia. Ultimately, the unexpected connection led to a deeper understanding of its fundamental role in the biology of neuromodulatory neurons, learning, and memory.
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Affiliation(s)
- Nicole Calakos
- Department of Neurology
- Department of Neurobiology, and
- Department of Cell Biology, Duke University Medical Center, Durham, North Carolina, USA
- Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, Chevy Chase, Maryland, USA
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19
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Moon S, Lee HH, Archer-Hartmann S, Nagai N, Mubasher Z, Parappurath M, Ahmed L, Ramos RL, Kimata K, Azadi P, Cai W, Zhao JY. Knockout of the intellectual disability-linked gene Hs6st2 in mice decreases heparan sulfate 6-O-sulfation, impairs dendritic spines of hippocampal neurons, and affects memory. Glycobiology 2024; 34:cwad095. [PMID: 38015989 PMCID: PMC10969535 DOI: 10.1093/glycob/cwad095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2023] Open
Abstract
Heparan sulfate (HS) is a linear polysaccharide that plays a key role in cellular signaling networks. HS functions are regulated by its 6-O-sulfation, which is catalyzed by three HS 6-O-sulfotransferases (HS6STs). Notably, HS6ST2 is mainly expressed in the brain and HS6ST2 mutations are linked to brain disorders, but the underlying mechanisms remain poorly understood. To determine the role of Hs6st2 in the brain, we carried out a series of molecular and behavioral assessments on Hs6st2 knockout mice. We first carried out strong anion exchange-high performance liquid chromatography and found that knockout of Hs6st2 moderately decreases HS 6-O-sulfation levels in the brain. We then assessed body weights and found that Hs6st2 knockout mice exhibit increased body weight, which is associated with abnormal metabolic pathways. We also performed behavioral tests and found that Hs6st2 knockout mice showed memory deficits, which recapitulate patient clinical symptoms. To determine the molecular mechanisms underlying the memory deficits, we used RNA sequencing to examine transcriptomes in two memory-related brain regions, the hippocampus and cerebral cortex. We found that knockout of Hs6st2 impairs transcriptome in the hippocampus, but only mildly in the cerebral cortex. Furthermore, the transcriptome changes in the hippocampus are enriched in dendrite and synapse pathways. We also found that knockout of Hs6st2 decreases HS levels and impairs dendritic spines in hippocampal CA1 pyramidal neurons. Taken together, our study provides novel molecular and behavioral insights into the role of Hs6st2 in the brain, which facilitates a better understanding of HS6ST2 and HS-linked brain disorders.
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Affiliation(s)
- Sohyun Moon
- Department of Biomedical Sciences, New York Institute of Technology College of Osteopathic Medicine, Northern Boulevard, P.O. Box 8000, Old Westbury, New York 11568, United States
| | - Hiu Ham Lee
- Department of Biomedical Sciences, New York Institute of Technology College of Osteopathic Medicine, Northern Boulevard, P.O. Box 8000, Old Westbury, New York 11568, United States
| | - Stephanie Archer-Hartmann
- Complex Carbohydrate Research Center, 315 Riverbend Road, University of Georgia, Athens, GA 30602, United States
| | - Naoko Nagai
- Institute for Molecular Science of Medicine, Aichi Medical University, 1-1 Yazakokarimata, Nagakute, Aichi 480-1195, Japan
| | - Zainab Mubasher
- Department of Biomedical Sciences, New York Institute of Technology College of Osteopathic Medicine, Northern Boulevard, P.O. Box 8000, Old Westbury, New York 11568, United States
| | - Mahima Parappurath
- Department of Biomedical Sciences, New York Institute of Technology College of Osteopathic Medicine, Northern Boulevard, P.O. Box 8000, Old Westbury, New York 11568, United States
| | - Laiba Ahmed
- Department of Biomedical Sciences, New York Institute of Technology College of Osteopathic Medicine, Northern Boulevard, P.O. Box 8000, Old Westbury, New York 11568, United States
| | - Raddy L Ramos
- Department of Biomedical Sciences, New York Institute of Technology College of Osteopathic Medicine, Northern Boulevard, P.O. Box 8000, Old Westbury, New York 11568, United States
| | - Koji Kimata
- Multidisciplinary Pain Center, Aichi Medical University, 1-1 Yazakokarimata, Nagakute, Aichi 480-1195, Japan
| | - Parastoo Azadi
- Complex Carbohydrate Research Center, 315 Riverbend Road, University of Georgia, Athens, GA 30602, United States
| | - Weikang Cai
- Department of Biomedical Sciences, New York Institute of Technology College of Osteopathic Medicine, Northern Boulevard, P.O. Box 8000, Old Westbury, New York 11568, United States
| | - Jerry Yingtao Zhao
- Department of Biomedical Sciences, New York Institute of Technology College of Osteopathic Medicine, Northern Boulevard, P.O. Box 8000, Old Westbury, New York 11568, United States
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20
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Hooshmandi M, Wong C, Lister KC, Brown N, Cai W, Ho-Tieng D, Stecum P, Backman T, Kostantin E, Khoutorsky A. Protocol for measuring protein synthesis in specific cell types in the mouse brain using in vivo non-canonical amino acid tagging. STAR Protoc 2024; 5:102775. [PMID: 38085640 PMCID: PMC10783633 DOI: 10.1016/j.xpro.2023.102775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Revised: 10/09/2023] [Accepted: 11/29/2023] [Indexed: 01/14/2024] Open
Abstract
The fluorescent non-canonical amino acid tagging (FUNCAT) technique has been used to visualize newly synthesized proteins in cell lines and tissues. Here, we present a protocol for measuring protein synthesis in specific cell types in the mouse brain using in vivo FUNCAT. We describe steps for metabolically labeling newly synthesized proteins with azidohomoalanine, which introduces an azide group into the polypeptide. We then detail procedures for binding a fluorophore-conjugated alkyne to the azide group to allow its visualization. For complete details on the use and execution of this protocol, please refer to tom Dieck et al. (2012)1 and Hooshmandi et al. (2023).2.
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Affiliation(s)
- Mehdi Hooshmandi
- Department of Anesthesia and Faculty of Dental Medicine and Oral Health Sciences, McGill University, Montreal, QC, Canada.
| | - Calvin Wong
- Department of Anesthesia and Faculty of Dental Medicine and Oral Health Sciences, McGill University, Montreal, QC, Canada
| | - Kevin C Lister
- Department of Anesthesia and Faculty of Dental Medicine and Oral Health Sciences, McGill University, Montreal, QC, Canada
| | - Nicole Brown
- Department of Anesthesia and Faculty of Dental Medicine and Oral Health Sciences, McGill University, Montreal, QC, Canada
| | - Weihua Cai
- Department of Anesthesia and Faculty of Dental Medicine and Oral Health Sciences, McGill University, Montreal, QC, Canada
| | - David Ho-Tieng
- Department of Anesthesia and Faculty of Dental Medicine and Oral Health Sciences, McGill University, Montreal, QC, Canada
| | - Patricia Stecum
- Department of Anesthesia and Faculty of Dental Medicine and Oral Health Sciences, McGill University, Montreal, QC, Canada
| | - Thomas Backman
- Department of Anesthesia and Faculty of Dental Medicine and Oral Health Sciences, McGill University, Montreal, QC, Canada
| | - Elie Kostantin
- Clinical Department of Laboratory Medicine, Cite-de-la-Sante Hospital, Optilab LLL and University of Montreal, Montreal, QC, Canada
| | - Arkady Khoutorsky
- Department of Anesthesia and Faculty of Dental Medicine and Oral Health Sciences, McGill University, Montreal, QC, Canada; Alan Edwards Centre for Research on Pain, McGill University, Montreal, QC, Canada.
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21
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Kommaddi RP, Gowaikar R, P A H, Diwakar L, Singh K, Mondal A. Akt activation ameliorates deficits in hippocampal-dependent memory and activity-dependent synaptic protein synthesis in an Alzheimer's disease mouse model. J Biol Chem 2024; 300:105619. [PMID: 38182004 PMCID: PMC10839450 DOI: 10.1016/j.jbc.2023.105619] [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: 08/24/2023] [Revised: 12/22/2023] [Accepted: 12/24/2023] [Indexed: 01/07/2024] Open
Abstract
Protein kinase-B (Akt) and the mechanistic target of rapamycin (mTOR) signaling pathways are implicated in Alzheimer's disease (AD) pathology. Akt/mTOR signaling pathways, activated by external inputs, enable new protein synthesis at the synapse and synaptic plasticity. The molecular mechanisms impeding new protein synthesis at the synapse in AD pathogenesis remain elusive. Here, we aimed to understand the molecular mechanisms prior to the manifestation of histopathological hallmarks by characterizing Akt1/mTOR signaling cascades and new protein synthesis in the hippocampus of WT and amyloid precursor protein/presenilin-1 (APP/PS1) male mice. Intriguingly, compared to those in WT mice, we found significant decreases in pAkt1, pGSK3β, pmTOR, pS6 ribosomal protein, and p4E-BP1 levels in both post nuclear supernatant and synaptosomes isolated from the hippocampus of one-month-old (presymptomatic) APP/PS1 mice. In synaptoneurosomes prepared from the hippocampus of presymptomatic APP/PS1 mice, activity-dependent protein synthesis at the synapse was impaired and this deficit was sustained in young adults. In hippocampal neurons from C57BL/6 mice, downregulation of Akt1 precluded synaptic activity-dependent protein synthesis at the dendrites but not in the soma. In three-month-old APP/PS1 mice, Akt activator (SC79) administration restored deficits in memory recall and activity-dependent synaptic protein synthesis. C57BL/6 mice administered with an Akt inhibitor (MK2206) resulted in memory recall deficits compared to those treated with vehicle. We conclude that dysregulation of Akt1/mTOR and its downstream signaling molecules in the hippocampus contribute to memory recall deficits and loss of activity-dependent synaptic protein synthesis. In AD mice, however, Akt activation ameliorates deficits in memory recall and activity-dependent synaptic protein synthesis.
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Affiliation(s)
| | - Ruturaj Gowaikar
- Centre for Neuroscience, Indian Institute of Science, Bangalore, India
| | - Haseena P A
- Centre for Brain Research, Indian Institute of Science, Bangalore, India; Manipal Academy of Higher Education, Manipal, India
| | - Latha Diwakar
- Centre for Brain Research, Indian Institute of Science, Bangalore, India
| | - Kunal Singh
- Centre for Neuroscience, Indian Institute of Science, Bangalore, India
| | - Amrita Mondal
- Centre for Brain Research, Indian Institute of Science, Bangalore, India
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22
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Paul BD, Pieper AA. Neuroprotective Roles of the Biliverdin Reductase-A/Bilirubin Axis in the Brain. Biomolecules 2024; 14:155. [PMID: 38397392 PMCID: PMC10887292 DOI: 10.3390/biom14020155] [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: 11/27/2023] [Revised: 01/24/2024] [Accepted: 01/25/2024] [Indexed: 02/25/2024] Open
Abstract
Biliverdin reductase-A (BVRA) is a multi-functional enzyme with a multitude of important roles in physiologic redox homeostasis. Classically, BVRA is well known for converting the heme metabolite biliverdin to bilirubin, which is a potent antioxidant in both the periphery and the brain. However, BVRA additionally participates in many neuroprotective signaling cascades in the brain that preserve cognition. Here, we review the neuroprotective roles of BVRA and bilirubin in the brain, which together constitute a BVRA/bilirubin axis that influences healthy aging and cognitive function.
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Affiliation(s)
- Bindu D. Paul
- Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Lieber Institute for Brain Development, Baltimore, MD 21205, USA
| | - Andrew A. Pieper
- Department of Psychiatry, Case Western Reserve University, Cleveland, OH 44106, USA
- Brain Health Medicines Center, Harrington Discovery Institute, University Hospitals Cleveland Medical Center, Cleveland, OH 44106, USA
- Geriatric Psychiatry, GRECC, Louis Stokes Cleveland VA Medical Center, Cleveland, OH 44106, USA
- Institute for Transformative Molecular Medicine, School of Medicine, Case Western Reserve University, Cleveland, OH 44106, USA
- Department of Pathology, School of Medicine, Case Western Reserve University, Cleveland, OH 44106, USA
- Department of Neurosciences, School of Medicine, Case Western Reserve University, Cleveland, OH 44106, USA
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23
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Abdelmaksoud NM, Sallam AAM, Abulsoud AI, El-Dakroury WA, Abdel Mageed SS, Al-Noshokaty TM, Elrebehy MA, Elshaer SS, Mahmoud NA, Fathi D, Rizk NI, Elballal MS, Mohammed OA, Abdel-Reheim MA, Zaki MB, Saber S, Doghish AS. Unraveling the role of miRNAs in the diagnosis, progression, and therapeutic intervention of Alzheimer's disease. Pathol Res Pract 2024; 253:155007. [PMID: 38061270 DOI: 10.1016/j.prp.2023.155007] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2023] [Revised: 11/28/2023] [Accepted: 11/30/2023] [Indexed: 01/24/2024]
Abstract
Alzheimer's disease (AD) is a multifaceted, advancing neurodegenerative illness that is responsible for most cases of neurological impairment and dementia in the aged population. As the disease progresses, affected individuals may experience cognitive decline, linguistic problems, affective instability, and behavioral changes. The intricate nature of AD reflects the altered molecular mechanisms participating in the affected human brain. MicroRNAs (miRNAs, miR) are essential for the intricate control of gene expression in neurobiology. miRNAs exert their influence by modulating the transcriptome of brain cells, which typically exhibit substantial genetic activity, encompassing gene transcription and mRNA production. Presently, comprehensive studies are being conducted on AD to identify miRNA-based signatures that are indicative of the disease pathophysiology. These findings can contribute to the advancement of our understanding of the mechanisms underlying this disorder and can inform the development of therapeutic interventions based on miRNA and related RNA molecules. Therefore, this comprehensive review provides a detailed holistic analysis of the latest advances discussing the emerging role of miRNAs in the progression of AD and their possible application as potential biomarkers and targets for therapeutic interventions in future studies.
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Affiliation(s)
| | - Al-Aliaa M Sallam
- Department of Biochemistry, Faculty of Pharmacy, Badr University in Cairo (BUC), Badr City, Cairo 11829, Egypt
| | - Ahmed I Abulsoud
- Biochemistry Department, Faculty of Pharmacy, Heliopolis University, Cairo 11785, Egypt; Biochemistry and Molecular Biology Department, Faculty of Pharmacy (Boys), Al-Azhar University, Nasr City 11231, Cairo, Egypt.
| | - Walaa A El-Dakroury
- Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Badr University in Cairo (BUC), Badr City, Cairo 11829, Egypt
| | - Sherif S Abdel Mageed
- Pharmacology and Toxicology Department, Faculty of Pharmacy, Badr University in Cairo (BUC), Badr City, Cairo 11829, Egypt
| | - Tohada M Al-Noshokaty
- Biochemistry Department, Faculty of Pharmacy, Heliopolis University, Cairo 11785, Egypt
| | - Mahmoud A Elrebehy
- Department of Biochemistry, Faculty of Pharmacy, Badr University in Cairo (BUC), Badr City, Cairo 11829, Egypt
| | - Shereen Saeid Elshaer
- Biochemistry Department, Faculty of Pharmacy, Heliopolis University, Cairo 11785, Egypt; Department of Biochemistry, Faculty of Pharmacy (Girls), Al-Azhar University, Nasr City, Cairo 11823, Egypt
| | - Naira Ali Mahmoud
- Microbiology and Immunology Department, Faculty of Pharmacy, Badr University in Cairo (BUC), Badr City, Cairo 11829, Egypt
| | - Doaa Fathi
- Biochemistry Department, Faculty of Pharmacy, Heliopolis University, Cairo 11785, Egypt
| | - Nehal I Rizk
- Biochemistry Department, Faculty of Pharmacy, Heliopolis University, Cairo 11785, Egypt
| | - Mohammed S Elballal
- Department of Biochemistry, Faculty of Pharmacy, Badr University in Cairo (BUC), Badr City, Cairo 11829, Egypt
| | - Osama A Mohammed
- Department of Pharmacology, College of Medicine, University of Bisha, Bisha 61922, Saudi Arabia
| | - Mustafa Ahmed Abdel-Reheim
- Department of Pharmaceutical Sciences, College of Pharmacy, Shaqra University, Shaqra 11961, Saudi Arabia; Department of Pharmacology and Toxicology, Faculty of Pharmacy, Beni-Suef University, Beni, Suef 62521, Egypt.
| | - Mohamed Bakr Zaki
- Department of Biochemistry, Faculty of Pharmacy, University of Sadat City, Menoufia 32897, Egypt
| | - Sameh Saber
- Department of Pharmacology, Faculty of Pharmacy, Delta University for Science and Technology, Gamasa 11152, Egypt
| | - Ahmed S Doghish
- Department of Biochemistry, Faculty of Pharmacy, Badr University in Cairo (BUC), Badr City, Cairo 11829, Egypt; Biochemistry and Molecular Biology Department, Faculty of Pharmacy (Boys), Al-Azhar University, Nasr City 11231, Cairo, Egypt.
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24
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Chen TJ, Hung HS, Cheng TL, Wang DC. Histone deacetylase inhibitor attenuates the effects of 27-hydroxycholesterol on the rat brain. Neurosci Lett 2024; 818:137533. [PMID: 37865186 DOI: 10.1016/j.neulet.2023.137533] [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: 08/21/2023] [Revised: 10/17/2023] [Accepted: 10/18/2023] [Indexed: 10/23/2023]
Abstract
Hypercholesterolemia is a risk factor for Alzheimer's disease (AD). Plasma cholesterol does not pass the blood-brain barrier whereas its metabolite 27-hydroxycholesterol (27-OHC) can enter the brain. High 27-OHC in the brain has been suggested to mediate hypercholesterolemia-induced impairments of learning and memory through promoting amyloid-β accumulation and facilitating synaptic disruption. In AD brains, the activity of histone deacetylase (HDAC) is elevated. Treating AD animals with HDAC inhibitors decreases amyloid-β levels and synaptic damages, which leads to memory improvement. Whether HDAC activity is involved in the actions of 27-OHC is still uncertain. In this study, 4 weekly injections of 27-OHC/vehicle were given to rats followed by 3 daily injections of HDAC inhibitor trichostatin (TSA)/vehicle. The results of Morris water maze test reveal that all rats have intact spatial learning ability during the 5-d training phase. However, the behavioral performance during the probe trial was impaired by 27-OHC treatment, which was improved by adding TSA treatments. Furthermore, 27-OHC treatments reduced the hippocampal levels of acetylated histone H3, acetylated α tubulin, insulin-degrading enzyme and postsynaptic protein PSD-95, indicating that 27-OHC treatments may induce enhanced HDAC activity, decreased amyloid-β clearance and synaptic disruption. All reduced levels returned to the basal levels by adding TSA treatments. These findings support our hypothesis that HDAC activity is enhanced following long-term exposure to excess 27-OHC.
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Affiliation(s)
- Tsan-Ju Chen
- Department of Physiology, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan; Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung 807, Taiwan
| | - Hui-Shan Hung
- Department of Physiology, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan
| | - Tsung-Lin Cheng
- Department of Physiology, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan; Orthopaedic Research Center, Kaohsiung Medical University, Kaohsiung 807, Taiwan; Regeneration Medicine and Cell Therapy Research Center, Kaohsiung Medical University, Kaohsiung 807, Taiwan
| | - Dean-Chuan Wang
- Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung 807, Taiwan; Department of Sports Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan.
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25
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Fetterly TL, Catalfio AM, Ferrario CR. Effects of junk-food on food-motivated behavior and nucleus accumbens glutamate plasticity; insights into the mechanism of calcium-permeable AMPA receptor recruitment. Neuropharmacology 2024; 242:109772. [PMID: 37898332 PMCID: PMC10883075 DOI: 10.1016/j.neuropharm.2023.109772] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Revised: 10/03/2023] [Accepted: 10/17/2023] [Indexed: 10/30/2023]
Abstract
In rats, eating obesogenic diets increases calcium-permeable AMPA receptor (CP-AMPAR) transmission in the nucleus accumbens (NAc) core, and enhances food-motivated behavior. Interestingly, these diet-induced alterations in NAc transmission are pronounced and sustained in obesity-prone (OP) male rats and absent in obesity-resistant (OR) populations. However, effects of diet manipulation on food motivation, and the mechanisms underlying this NAc plasticity in OPs is unknown. Using male selectively-bred OP and OR rats, we assessed food-motivated behavior following ad lib access to chow (CH), junk-food (JF), or 10d of JF followed by a return to chow diet (JF-Dep). Motivation for food was greater in OP than OR rats, as expected. However, JF-Dep only produced enhancements in food-seeking in OP groups, while continuous JF access reduced food-seeking in both OPs and ORs. Additionally, optogenetic, chemogenetic, and pharmacological approaches were used to examine NAc CP-AMPAR recruitment following diet manipulation and ex vivo treatment of brain slices. Reducing excitatory transmission in the NAc was sufficient to recruit CP-AMPARs to synapses in OPs, but not ORs. In OPs, JF-induced increases in CP-AMPARs occurred in mPFC-, but not BLA-to-NAc inputs. Together results show that diet differentially affects behavioral and neural plasticity in obesity susceptible populations. We also identify conditions for acute recruitment of NAc CP-AMPARs; these results suggest that synaptic scaling mechanisms contribute to NAc CP-AMPAR recruitment. Overall, this work helps elucidate how diet interacts with obesity susceptibility to influence food-motivated behavior and extends our fundamental understanding of NAc CP-AMPAR recruitment.
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Affiliation(s)
- Tracy L Fetterly
- Department of Pharmacology, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Amanda M Catalfio
- Department of Pharmacology, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Carrie R Ferrario
- Department of Pharmacology, University of Michigan, Ann Arbor, MI, 48109, USA; Psychology Department (Biopsychology) University of Michigan, Ann Arbor, MI, 48109, USA.
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26
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Atta-Ur-Rahman. Protein Folding and Molecular Basis of Memory: Molecular Vibrations and Quantum Entanglement as Basis of Consciousness. Curr Med Chem 2024; 31:258-265. [PMID: 37424348 DOI: 10.2174/0929867331666230707123345] [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: 04/30/2023] [Revised: 06/28/2023] [Accepted: 06/28/2023] [Indexed: 07/11/2023]
Affiliation(s)
- Atta-Ur-Rahman
- Kings College, University of Cambridge, Cambridge CB2 1st, United Kingdom
- H.E.J. Research Institute of Chemistry, International Center for Chemical and Biological Sciences, University of Karachi, Karachi 75270, Pakistan
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27
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Ibrahim MJ, Baiju V, Sen S, Chandran PP, Ashraf GM, Haque S, Ahmad F. Utilities of Isolated Nerve Terminals in Ex Vivo Analyses of Protein Translation in (Patho)physiological Brain States: Focus on Alzheimer's Disease. Mol Neurobiol 2024; 61:91-103. [PMID: 37582987 DOI: 10.1007/s12035-023-03562-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Accepted: 08/07/2023] [Indexed: 08/17/2023]
Abstract
Synapses are the cellular substrates of higher-order brain functions, and their dysfunction is an early and primary pathogenic mechanism across several neurological disorders. In particular, Alzheimer's disease (AD) is categorized by prodromal structural and functional synaptic deficits, prior to the advent of classical behavioral and pathological features. Recent research has shown that the development, maintenance, and plasticity of synapses depend on localized protein translation. Synaptosomes and synaptoneurosomes are biochemically isolated synaptic terminal preparations which have long been used to examine a variety of synaptic processes ex vivo in both healthy and pathological conditions. These ex vivo preparations preserve the mRNA species and the protein translational machinery. Hence, they are excellent in organello tools for the study of alterations in mRNA levels and protein translation in neuropathologies. Evaluation of synapse-specific basal and activity-driven de novo protein translation activity can be conveniently performed in synaptosomal/synaptoneurosomal preparations from both rodent and human brain tissue samples. This review gives a quick overview of the methods for isolating synaptosomes and synaptoneurosomes before discussing the studies that have utilized these preparations to study localized synapse-specific protein translation in (patho)physiological situations, with an emphasis on AD. While the review is not an exhaustive accumulation of all the studies evaluating synaptic protein translation using the synaptosomal model, the aim is to assemble the most relevant studies that have done so. The hope is to provide a suitable research platform to aid neuroscientists to utilize the synaptosomal/synaptoneurosomal models to evaluate the molecular mechanisms of synaptic dysfunction within the specific confines of mRNA localization and protein translation research.
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Affiliation(s)
- Mohammad Jasim Ibrahim
- Department of Biotechnology, Vellore Institute of Technology, Vellore, Tamil Nadu, India, 632014
| | - Viswanath Baiju
- Department of Biotechnology, Vellore Institute of Technology, Vellore, Tamil Nadu, India, 632014
| | - Shivam Sen
- Department of Biotechnology, Vellore Institute of Technology, Vellore, Tamil Nadu, India, 632014
| | - Pranav Prathapa Chandran
- Department of Biotechnology, Vellore Institute of Technology, Vellore, Tamil Nadu, India, 632014
| | - Ghulam Md Ashraf
- University of Sharjah, College of Health Sciences, and Research Institute for Medical and Health Sciences, Department of Medical Laboratory Sciences, University City, 27272, Sharjah, United Arab Emirates.
| | - Shafiul Haque
- Research and Scientific Studies Unit, College of Nursing and Allied Health Sciences, Jazan University, 45142, Jazan, Saudi Arabia
- Gilbert and Rose-Marie Chagoury School of Medicine, Lebanese American University, Beirut, Lebanon
- Centre of Medical and Bio-Allied Health Sciences Research, Ajman University, Ajman, United Arab Emirates
| | - Faraz Ahmad
- Department of Biotechnology, Vellore Institute of Technology, Vellore, Tamil Nadu, India, 632014.
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28
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Welle TM, Rajgor D, Garcia JD, Kareemo D, Zych SM, Gookin SE, Martinez TP, Dell’Acqua ML, Ford CP, Kennedy MJ, Smith KR. miRNA-mediated control of gephyrin synthesis drives sustained inhibitory synaptic plasticity. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.12.570420. [PMID: 38168421 PMCID: PMC10760056 DOI: 10.1101/2023.12.12.570420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
Activity-dependent protein synthesis is crucial for many long-lasting forms of synaptic plasticity. However, our understanding of the translational mechanisms controlling inhibitory synapses is limited. One distinct form of inhibitory long-term potentiation (iLTP) enhances postsynaptic clusters of GABAARs and the primary inhibitory scaffold, gephyrin, to promote sustained synaptic strengthening. While we previously found that persistent iLTP requires mRNA translation, the precise mechanisms controlling gephyrin translation during this process remain unknown. Here, we identify miR153 as a novel regulator of Gphn mRNA translation which controls gephyrin protein levels and synaptic clustering, ultimately impacting GABAergic synaptic structure and function. We find that iLTP induction downregulates miR153, reversing its translational suppression of Gphn mRNA and allowing for increased de novo gephyrin protein synthesis and synaptic clustering during iLTP. Finally, we find that reduced miR153 expression during iLTP is driven by an excitation-transcription coupling pathway involving calcineurin, NFAT and HDACs, which also controls the miRNA-dependent upregulation of GABAARs. Overall, this work delineates a miRNA-dependent post-transcriptional mechanism that controls the expression of the key synaptic scaffold, gephyrin, and may converge with parallel miRNA pathways to coordinate gene upregulation to maintain inhibitory synaptic plasticity.
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Affiliation(s)
- Theresa M. Welle
- Department of Pharmacology, University of Colorado School of Medicine, Anschutz Medical Campus, 12800 East 19th Avenue, Aurora, CO 80045
- T.M.W and D.R. contributed equally to this work
| | - Dipen Rajgor
- Department of Pharmacology, University of Colorado School of Medicine, Anschutz Medical Campus, 12800 East 19th Avenue, Aurora, CO 80045
- T.M.W and D.R. contributed equally to this work
| | - Joshua D. Garcia
- Department of Pharmacology, University of Colorado School of Medicine, Anschutz Medical Campus, 12800 East 19th Avenue, Aurora, CO 80045
| | - Dean Kareemo
- Department of Pharmacology, University of Colorado School of Medicine, Anschutz Medical Campus, 12800 East 19th Avenue, Aurora, CO 80045
| | - Sarah M. Zych
- Department of Pharmacology, University of Colorado School of Medicine, Anschutz Medical Campus, 12800 East 19th Avenue, Aurora, CO 80045
| | - Sara E. Gookin
- Department of Pharmacology, University of Colorado School of Medicine, Anschutz Medical Campus, 12800 East 19th Avenue, Aurora, CO 80045
| | - Tyler P. Martinez
- Department of Pharmacology, University of Colorado School of Medicine, Anschutz Medical Campus, 12800 East 19th Avenue, Aurora, CO 80045
| | - Mark L. Dell’Acqua
- Department of Pharmacology, University of Colorado School of Medicine, Anschutz Medical Campus, 12800 East 19th Avenue, Aurora, CO 80045
| | - Christopher P. Ford
- Department of Pharmacology, University of Colorado School of Medicine, Anschutz Medical Campus, 12800 East 19th Avenue, Aurora, CO 80045
| | - Matthew J. Kennedy
- Department of Pharmacology, University of Colorado School of Medicine, Anschutz Medical Campus, 12800 East 19th Avenue, Aurora, CO 80045
| | - Katharine R. Smith
- Department of Pharmacology, University of Colorado School of Medicine, Anschutz Medical Campus, 12800 East 19th Avenue, Aurora, CO 80045
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29
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Fitch WT. Cellular computation and cognition. Front Comput Neurosci 2023; 17:1107876. [PMID: 38077750 PMCID: PMC10702520 DOI: 10.3389/fncom.2023.1107876] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Accepted: 10/09/2023] [Indexed: 05/28/2024] Open
Abstract
Contemporary neural network models often overlook a central biological fact about neural processing: that single neurons are themselves complex, semi-autonomous computing systems. Both the information processing and information storage abilities of actual biological neurons vastly exceed the simple weighted sum of synaptic inputs computed by the "units" in standard neural network models. Neurons are eukaryotic cells that store information not only in synapses, but also in their dendritic structure and connectivity, as well as genetic "marking" in the epigenome of each individual cell. Each neuron computes a complex nonlinear function of its inputs, roughly equivalent in processing capacity to an entire 1990s-era neural network model. Furthermore, individual cells provide the biological interface between gene expression, ongoing neural processing, and stored long-term memory traces. Neurons in all organisms have these properties, which are thus relevant to all of neuroscience and cognitive biology. Single-cell computation may also play a particular role in explaining some unusual features of human cognition. The recognition of the centrality of cellular computation to "natural computation" in brains, and of the constraints it imposes upon brain evolution, thus has important implications for the evolution of cognition, and how we study it.
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Affiliation(s)
- W. Tecumseh Fitch
- Faculty of Life Sciences and Vienna Cognitive Science Hub, University of Vienna, Vienna, Austria
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30
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Dębowska W, Więdłocha M, Dębowska M, Kownacka Z, Marcinowicz P, Szulc A. Transcranial magnetic stimulation and ketamine: implications for combined treatment in depression. Front Neurosci 2023; 17:1267647. [PMID: 37954877 PMCID: PMC10637948 DOI: 10.3389/fnins.2023.1267647] [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: 07/27/2023] [Accepted: 10/09/2023] [Indexed: 11/14/2023] Open
Abstract
Drug-resistant mental disorders, particularly treatment-resistant depression, pose a significant medical and social problem. To address this challenge, modern psychiatry is constantly exploring the use of novel treatment methods, including biological treatments, such as transcranial magnetic stimulation (TMS), and novel rapid-acting antidepressants, such as ketamine. While both TMS and ketamine demonstrate high effectiveness in reducing the severity of depressive symptoms, some patients still do not achieve the desired improvement. Recent literature suggests that combining these two methods may yield even stronger and longer-lasting results. This review aims to consolidate knowledge in this area and elucidate the potential mechanisms of action underlying the increased efficacy of combined treatment, which would provide a foundation for the development and optimization of future treatment protocols.
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Affiliation(s)
- Weronika Dębowska
- Department of Psychiatry, Faculty of Health Sciences, Medical University of Warsaw, Warsaw, Poland
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31
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Abstract
According to the commonly accepted opinion, memory engrams are formed and stored at the level of neural networks due to a change in the strength of synaptic connections between neurons. This hypothesis of synaptic plasticity (HSP), formulated by Donald Hebb in the 1940s, continues to dominate the directions of experimental studies and the interpretations of experimental results in the field. The universal acceptance of the HSP has transformed it from a hypothesis into an incontrovertible theory. In this article, I show that the entire body of experimental and clinical data obtained in studies of long-term memory in mammals and humans is inconsistent with the HSP. Instead, these data suggest that long-term memory is formed and stored at the intracellular level where it is reliably protected from ongoing synaptic activity, including pathological epileptic activity. It seems that the generally accepted HSP became a serious obstacle to understanding the mechanisms of memory and that progress in this field requires rethinking this doctrine and shifting experimental efforts toward exploring the intracellular mechanisms.
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Affiliation(s)
- Yuri I Arshavsky
- BioCircuits Institute, University of California San Diego, La Jolla, CA, USA
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32
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Santos JL, Petsidou E, Saraogi P, Bartsch U, Gerber AP, Seibt J. Effect of Acute Enriched Environment Exposure on Brain Oscillations and Activation of the Translation Initiation Factor 4E-BPs at Synapses across Wakefulness and Sleep in Rats. Cells 2023; 12:2320. [PMID: 37759542 PMCID: PMC10528220 DOI: 10.3390/cells12182320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 09/15/2023] [Accepted: 09/18/2023] [Indexed: 09/29/2023] Open
Abstract
Brain plasticity is induced by learning during wakefulness and is consolidated during sleep. But the molecular mechanisms involved are poorly understood and their relation to experience-dependent changes in brain activity remains to be clarified. Localised mRNA translation is important for the structural changes at synapses supporting brain plasticity consolidation. The translation mTOR pathway, via phosphorylation of 4E-BPs, is known to be activate during sleep and contributes to brain plasticity, but whether this activation is specific to synapses is not known. We investigated this question using acute exposure of rats to an enriched environment (EE). We measured brain activity with EEGs and 4E-BP phosphorylation at cortical and cerebellar synapses with Western blot analyses. Sleep significantly increased the conversion of 4E-BPs to their hyperphosphorylated forms at synapses, especially after EE exposure. EE exposure increased oscillations in the alpha band during active exploration and in the theta-to-beta (4-30 Hz) range, as well as spindle density, during NREM sleep. Theta activity during exploration and NREM spindle frequency predicted changes in 4E-BP hyperphosphorylation at synapses. Hence, our results suggest a functional link between EEG and molecular markers of plasticity across wakefulness and sleep.
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Affiliation(s)
- José Lucas Santos
- Surrey Sleep Research Centre, School of Biosciences, Faculty of Health and Medical Sciences, University of Surrey, Guildford GU2 7XP, UK; (J.L.S.); (U.B.)
- Department of Microbial Sciences, School of Biosciences, Faculty of Health and Medical Sciences, University of Surrey, Guildford GU2 7XH, UK;
- Department of Physiology, Development and Neuroscience, University of Cambridge, Physiological Laboratory, Downing Street, Cambridge CB2 3EG, UK
| | - Evlalia Petsidou
- Undergraduate Programme in Biological Science, University of Surrey, Guildford GU2 7XH, UK
- Postgraduate Programme in Neuroscience (MSc), Cyprus Institute of Neurology and Genetics, Iroon Avenue 6, Egkomi 2371, Cyprus
| | - Pallavi Saraogi
- Undergraduate Programme in Biological Science, University of Surrey, Guildford GU2 7XH, UK
| | - Ullrich Bartsch
- Surrey Sleep Research Centre, School of Biosciences, Faculty of Health and Medical Sciences, University of Surrey, Guildford GU2 7XP, UK; (J.L.S.); (U.B.)
- UK Dementia Research Institute, Care Research & Technology Centre at Imperial College London and University of Surrey, Guildford GU2 7XH, UK
| | - André P. Gerber
- Department of Microbial Sciences, School of Biosciences, Faculty of Health and Medical Sciences, University of Surrey, Guildford GU2 7XH, UK;
| | - Julie Seibt
- Surrey Sleep Research Centre, School of Biosciences, Faculty of Health and Medical Sciences, University of Surrey, Guildford GU2 7XP, UK; (J.L.S.); (U.B.)
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Naskar A, Nayak A, Salaikumaran MR, Vishal SS, Gopal PP. Phase separation and pathologic transitions of RNP condensates in neurons: implications for amyotrophic lateral sclerosis, frontotemporal dementia and other neurodegenerative disorders. Front Mol Neurosci 2023; 16:1242925. [PMID: 37720552 PMCID: PMC10502346 DOI: 10.3389/fnmol.2023.1242925] [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: 06/20/2023] [Accepted: 08/21/2023] [Indexed: 09/19/2023] Open
Abstract
Liquid-liquid phase separation results in the formation of dynamic biomolecular condensates, also known as membrane-less organelles, that allow for the assembly of functional compartments and higher order structures within cells. Multivalent, reversible interactions between RNA-binding proteins (RBPs), including FUS, TDP-43, and hnRNPA1, and/or RNA (e.g., RBP-RBP, RBP-RNA, RNA-RNA), result in the formation of ribonucleoprotein (RNP) condensates, which are critical for RNA processing, mRNA transport, stability, stress granule assembly, and translation. Stress granules, neuronal transport granules, and processing bodies are examples of cytoplasmic RNP condensates, while the nucleolus and Cajal bodies are representative nuclear RNP condensates. In neurons, RNP condensates promote long-range mRNA transport and local translation in the dendrites and axon, and are essential for spatiotemporal regulation of gene expression, axonal integrity and synaptic function. Mutations of RBPs and/or pathologic mislocalization and aggregation of RBPs are hallmarks of several neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS), frontotemporal dementia (FTD), and Alzheimer's disease. ALS/FTD-linked mutations of RBPs alter the strength and reversibility of multivalent interactions with other RBPs and RNAs, resulting in aberrant phase transitions. These aberrant RNP condensates have detrimental functional consequences on mRNA stability, localization, and translation, and ultimately lead to compromised axonal integrity and synaptic function in disease. Pathogenic protein aggregation is dependent on various factors, and aberrant dynamically arrested RNP condensates may serve as an initial nucleation step for pathologic aggregate formation. Recent studies have focused on identifying mechanisms by which neurons resolve phase transitioned condensates to prevent the formation of pathogenic inclusions/aggregates. The present review focuses on the phase separation of neurodegenerative disease-linked RBPs, physiological functions of RNP condensates, and the pathologic role of aberrant phase transitions in neurodegenerative disease, particularly ALS/FTD. We also examine cellular mechanisms that contribute to the resolution of aberrant condensates in neurons, and potential therapeutic approaches to resolve aberrantly phase transitioned condensates at a molecular level.
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Affiliation(s)
- Aditi Naskar
- Department of Pathology, Yale School of Medicine, New Haven, CT, United States
| | - Asima Nayak
- Department of Pathology, Yale School of Medicine, New Haven, CT, United States
| | | | - Sonali S. Vishal
- Department of Pathology, Yale School of Medicine, New Haven, CT, United States
| | - Pallavi P. Gopal
- Department of Pathology, Yale School of Medicine, New Haven, CT, United States
- Program in Cellular Neuroscience, Neurodegeneration, and Repair, Yale School of Medicine, New Haven, CT, United States
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Daskalaki I, Markaki M, Gkikas I, Tavernarakis N. Local coordination of mRNA storage and degradation near mitochondria modulates C. elegans ageing. EMBO J 2023; 42:e112446. [PMID: 37427543 PMCID: PMC10425844 DOI: 10.15252/embj.2022112446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 06/10/2023] [Accepted: 06/17/2023] [Indexed: 07/11/2023] Open
Abstract
Mitochondria are central regulators of healthspan and lifespan, yet the intricate choreography of multiple, tightly controlled steps regulating mitochondrial biogenesis remains poorly understood. Here, we uncover a pivotal role for specific elements of the 5'-3' mRNA degradation pathway in the regulation of mitochondrial abundance and function. We find that the mRNA degradation and the poly-A tail deadenylase CCR4-NOT complexes form distinct foci in somatic Caenorhabditis elegans cells that physically and functionally associate with mitochondria. Components of these two multi-subunit complexes bind transcripts of nuclear-encoded mitochondria-targeted proteins to regulate mitochondrial biogenesis during ageing in an opposite manner. In addition, we show that balanced degradation and storage of mitochondria-targeted protein mRNAs are critical for mitochondrial homeostasis, stress resistance and longevity. Our findings reveal a multifaceted role of mRNA metabolism in mitochondrial biogenesis and show that fine-tuning of mRNA turnover and local translation control mitochondrial abundance and promote longevity in response to stress and during ageing.
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Affiliation(s)
- Ioanna Daskalaki
- Institute of Molecular Biology and BiotechnologyFoundation for Research and Technology‐HellasHeraklionGreece
- Department of Biology, School of Sciences and EngineeringUniversity of CreteHeraklionGreece
| | - Maria Markaki
- Institute of Molecular Biology and BiotechnologyFoundation for Research and Technology‐HellasHeraklionGreece
| | - Ilias Gkikas
- Institute of Molecular Biology and BiotechnologyFoundation for Research and Technology‐HellasHeraklionGreece
| | - Nektarios Tavernarakis
- Institute of Molecular Biology and BiotechnologyFoundation for Research and Technology‐HellasHeraklionGreece
- Division of Basic Sciences, School of MedicineUniversity of CreteHeraklionGreece
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Ament SA, Poulopoulos A. The brain's dark transcriptome: Sequencing RNA in distal compartments of neurons and glia. Curr Opin Neurobiol 2023; 81:102725. [PMID: 37196598 PMCID: PMC10524153 DOI: 10.1016/j.conb.2023.102725] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Revised: 03/22/2023] [Accepted: 04/02/2023] [Indexed: 05/19/2023]
Abstract
Transcriptomic approaches are powerful strategies to map the molecular diversity of cells in the brain. Single-cell genomic atlases have now been compiled for entire mammalian brains. However, complementary techniques are only just beginning to map the subcellular transcriptomes from distal cellular compartments. We review single-cell datasets alongside subtranscriptome data from the mammalian brain to explore the development of cellular and subcellular diversity. We discuss how single-cell RNA-seq misses transcripts localized away from cell bodies, which form the 'dark transcriptome' of the brain: a collection of subtranscriptomes in dendrites, axons, growth cones, synapses, and endfeet with important roles in brain development and function. Recent advances in subcellular transcriptome sequencing are beginning to reveal these elusive pools of RNA. We outline the success stories to date in uncovering the constituent subtranscriptomes of neurons and glia, as well as present the emerging toolkit that is accelerating the pace of subtranscriptome discovery.
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Affiliation(s)
- Seth A Ament
- Department of Psychiatry, UM-MIND, and Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Alexandros Poulopoulos
- Department of Pharmacology and UM-MIND, University of Maryland School of Medicine, Baltimore, MD, USA.
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Mullari M, Fossat N, Skotte NH, Asenjo-Martinez A, Humphreys DT, Bukh J, Kirkeby A, Scheel TKH, Nielsen ML. Characterising the RNA-binding protein atlas of the mammalian brain uncovers RBM5 misregulation in mouse models of Huntington's disease. Nat Commun 2023; 14:4348. [PMID: 37468457 DOI: 10.1038/s41467-023-39936-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Accepted: 06/30/2023] [Indexed: 07/21/2023] Open
Abstract
RNA-binding proteins (RBPs) are key players regulating RNA processing and are associated with disorders ranging from cancer to neurodegeneration. Here, we present a proteomics workflow for large-scale identification of RBPs and their RNA-binding regions in the mammalian brain identifying 526 RBPs. Analysing brain tissue from males of the Huntington's disease (HD) R6/2 mouse model uncovered differential RNA-binding of the alternative splicing regulator RBM5. Combining several omics workflows, we show that RBM5 binds differentially to transcripts enriched in pathways of neurodegeneration in R6/2 brain tissue. We further find these transcripts to undergo changes in splicing and demonstrate that RBM5 directly regulates these changes in human neurons derived from embryonic stem cells. Finally, we reveal that RBM5 interacts differently with several known huntingtin interactors and components of huntingtin aggregates. Collectively, we demonstrate the applicability of our method for capturing RNA interactor dynamics in the contexts of tissue and disease.
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Affiliation(s)
- Meeli Mullari
- Proteomics Program, Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
| | - Nicolas Fossat
- Copenhagen Hepatitis C Program (CO-HEP), Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- CO-HEP, Department of Infectious Diseases, Copenhagen University Hospital, Hvidovre, Denmark
| | - Niels H Skotte
- Proteomics Program, Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Andrea Asenjo-Martinez
- The Novo Nordisk Foundation Center for Stem Cell Medicine (reNEW) and Department of Neuroscience, University of Copenhagen, Copenhagen, Denmark
| | - David T Humphreys
- Victor Chang Cardiac Research Institute, Darlinghurst, NSW, 2010, Australia
| | - Jens Bukh
- Copenhagen Hepatitis C Program (CO-HEP), Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- CO-HEP, Department of Infectious Diseases, Copenhagen University Hospital, Hvidovre, Denmark
| | - Agnete Kirkeby
- The Novo Nordisk Foundation Center for Stem Cell Medicine (reNEW) and Department of Neuroscience, University of Copenhagen, Copenhagen, Denmark
- Wallenberg Center for Molecular Medicine (WCMM) and Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Troels K H Scheel
- Copenhagen Hepatitis C Program (CO-HEP), Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- CO-HEP, Department of Infectious Diseases, Copenhagen University Hospital, Hvidovre, Denmark
- Laboratory of Virology and Infectious Disease, The Rockefeller University, New York, NY, USA
| | - Michael L Nielsen
- Proteomics Program, Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
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Das S, Lituma PJ, Castillo PE, Singer RH. Maintenance of a short-lived protein required for long-term memory involves cycles of transcription and local translation. Neuron 2023; 111:2051-2064.e6. [PMID: 37100055 PMCID: PMC10330212 DOI: 10.1016/j.neuron.2023.04.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 01/03/2023] [Accepted: 04/03/2023] [Indexed: 04/28/2023]
Abstract
Activity-dependent expression of immediate early genes (IEGs) is critical for long-term synaptic remodeling and memory. It remains unknown how IEGs are maintained for memory despite rapid transcript and protein turnover. To address this conundrum, we monitored Arc, an IEG essential for memory consolidation. Using a knockin mouse where endogenous Arc alleles were fluorescently tagged, we performed real-time imaging of Arc mRNA dynamics in individual neurons in cultures and brain tissue. Unexpectedly, a single burst stimulation was sufficient to induce cycles of transcriptional reactivation in the same neuron. Subsequent transcription cycles required translation, whereby new Arc proteins engaged in autoregulatory positive feedback to reinduce transcription. The ensuing Arc mRNAs preferentially localized at sites marked by previous Arc protein, assembling a "hotspot" of translation, and consolidating "hubs" of dendritic Arc. These cycles of transcription-translation coupling sustain protein expression and provide a mechanism by which a short-lived event may support long-term memory.
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Affiliation(s)
- Sulagna Das
- Department of Cell Biology, Albert Einstein College of Medicine, Bronx, New York, NY 10461, USA; Program in RNA Biology, Albert Einstein College of Medicine, Bronx, New York, NY 10461, USA.
| | - Pablo J Lituma
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, New York, NY 10461, USA
| | - Pablo E Castillo
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, New York, NY 10461, USA; Department of Psychiatry and Behavioral Sciences, Albert Einstein College of Medicine, Bronx, New York, NY 10461, USA
| | - Robert H Singer
- Department of Cell Biology, Albert Einstein College of Medicine, Bronx, New York, NY 10461, USA; Program in RNA Biology, Albert Einstein College of Medicine, Bronx, New York, NY 10461, USA; Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, New York, NY 10461, USA.
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Ma T. Roles of eukaryotic elongation factor 2 kinase (eEF2K) in neuronal plasticity, cognition, and Alzheimer disease. J Neurochem 2023; 166:47-57. [PMID: 34796967 PMCID: PMC9117558 DOI: 10.1111/jnc.15541] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 10/19/2021] [Accepted: 11/15/2021] [Indexed: 01/04/2023]
Abstract
Understanding the molecular signaling mechanisms underlying cognition and neuronal plasticity would provide insights into the pathogenesis of neuronal disorders characterized by cognitive syndromes such as Alzheimer disease (AD). Phosphorylation of the mRNA translational factor eukaryotic elongation factor 2 (eEF2) by its specific kinase eEF2K is critically involved in protein synthesis regulation. In this review, we discussed recent studies on the roles of eEF2K/eEF2 signaling in the context of regulation/dysregulation of cognitive function and synaptic plasticity. We specifically focus on the discussion of recent evidence indicating suppression of eEF2K signaling as a potential novel therapeutic avenue for AD and related dementias (ADRDs).
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Affiliation(s)
- Tao Ma
- Department of Internal Medicine-Gerontology and Geriatric Medicine, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA
- Department of Physiology and Pharmacology, Wake Forest University School of Medicine
- Department of Neurobiology and Anatomy, Wake Forest University School of Medicine
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Huang YS, Mendez R, Fernandez M, Richter JD. CPEB and translational control by cytoplasmic polyadenylation: impact on synaptic plasticity, learning, and memory. Mol Psychiatry 2023; 28:2728-2736. [PMID: 37131078 PMCID: PMC10620108 DOI: 10.1038/s41380-023-02088-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2023] [Revised: 04/18/2023] [Accepted: 04/19/2023] [Indexed: 05/04/2023]
Abstract
The late 1990s were banner years in molecular neuroscience; seminal studies demonstrated that local protein synthesis, at or near synapses, was necessary for synaptic plasticity, the underlying cellular basis of learning and memory [1, 2]. The newly made proteins were proposed to "tag" the stimulated synapse, distinguishing it from naive synapses, thereby forming a cellular memory [3]. Subsequent studies demonstrated that the transport of mRNAs from soma to dendrite was linked with translational unmasking at synapses upon synaptic stimulation. It soon became apparent that one prevalent mechanism governing these events is cytoplasmic polyadenylation, and that among the proteins that control this process, CPEB, plays a central role in synaptic plasticity, and learning and memory. In vertebrates, CPEB is a family of four proteins, all of which regulate translation in the brain, that have partially overlapping functions, but also have unique characteristics and RNA binding properties that make them control different aspects of higher cognitive function. Biochemical analysis of the vertebrate CPEBs demonstrate them to respond to different signaling pathways whose output leads to specific cellular responses. In addition, the different CPEBs, when their functions go awry, result in pathophysiological phenotypes resembling specific human neurological disorders. In this essay, we review key aspects of the vertebrate CPEB proteins and cytoplasmic polyadenylation within the context of brain function.
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Affiliation(s)
- Yi-Shuian Huang
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan.
| | - Raul Mendez
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, 08028, Barcelona, Spain.
- Institució Catalana de Recerca i Estudis Avançats (ICREA), 08010, Barcelona, Spain.
| | | | - Joel D Richter
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA, 01605, USA.
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Seidel F, Fluiter K, Kleemann R, Worms N, van Nieuwkoop A, Caspers MPM, Grigoriadis N, Kiliaan AJ, Baas F, Michailidou I, Morrison MC. Ldlr-/-.Leiden mice develop neurodegeneration, age-dependent astrogliosis and obesity-induced changes in microglia immunophenotype which are partly reversed by complement component 5 neutralizing antibody. Front Cell Neurosci 2023; 17:1205261. [PMID: 37457817 PMCID: PMC10346859 DOI: 10.3389/fncel.2023.1205261] [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: 04/13/2023] [Accepted: 06/12/2023] [Indexed: 07/18/2023] Open
Abstract
Introduction Obesity has been linked to vascular dysfunction, cognitive impairment and neurodegenerative diseases. However, experimental models that recapitulate brain pathology in relation to obesity and vascular dysfunction are still lacking. Methods In this study we performed the histological and histochemical characterization of brains from Ldlr-/-.Leiden mice, an established model for obesity and associated vascular disease. First, HFD-fed 18 week-old and 50 week-old Ldlr-/-.Leiden male mice were compared with age-matched C57BL/6J mice. We then assessed the effect of high-fat diet (HFD)-induced obesity on brain pathology in Ldlr-/-.Leiden mice and tested whether a treatment with an anti-complement component 5 antibody, a terminal complement pathway inhibitor recently shown to reduce vascular disease, can attenuate neurodegeneration and neuroinflammation. Histological analyses were complemented with Next Generation Sequencing (NGS) analyses of the hippocampus to unravel molecular pathways underlying brain histopathology. Results We show that chow-fed Ldlr-/-.Leiden mice have more severe neurodegeneration and show an age-dependent astrogliosis that is not observed in age-matched C57BL/6J controls. This was substantiated by pathway enrichment analysis using the NGS data which showed that oxidative phosphorylation, EIF2 signaling and mitochondrial dysfunction pathways, all associated with neurodegeneration, were significantly altered in the hippocampus of Ldlr-/-.Leiden mice compared with C57BL/6J controls. Obesity-inducing HFD-feeding did not aggravate neurodegeneration and astrogliosis in Ldlr-/-.Leiden mice. However, brains from HFD-fed Ldlr-/-.Leiden mice showed reduced IBA-1 immunoreactivity and increased CD68 immunoreactivity compared with chow-fed Ldlr-/-.Leiden mice, indicating alteration of microglial immunophenotype by HFD feeding. The systemic administration of an anti-C5 treatment partially restored the HFD effect on microglial immunophenotype. In addition, NGS data of hippocampi from Ldlr-/-.Leiden mice showed that HFD feeding affected multiple molecular pathways relative to chow-fed controls: HFD notably inactivated synaptogenesis and activated neuroinflammation pathways. The anti-C5 treatment restored the HFD-induced effect on molecular pathways to a large extent. Conclusion This study shows that the Ldlr-/-.Leiden mouse model is suitable to study brain histopathology and associated biological processes in a context of obesity and provides evidence of the potential therapeutic value of anti-complement therapy against obesity-induced neuroinflammation.
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Affiliation(s)
- Florine Seidel
- Department of Metabolic Health Research, Netherlands Organisation for Applied Scientific Research (TNO), Leiden, Netherlands
- Department of Medical Imaging, Anatomy, Preclinical Imaging Center (PRIME), Radboud Alzheimer Center, Donders Institute for Brain, Cognition, and Behavior, Radboud University Medical Center, Nijmegen, Netherlands
| | - Kees Fluiter
- Department of Clinical Genetics, Leiden University Medical Center, Leiden, Netherlands
| | - Robert Kleemann
- Department of Metabolic Health Research, Netherlands Organisation for Applied Scientific Research (TNO), Leiden, Netherlands
| | - Nicole Worms
- Department of Metabolic Health Research, Netherlands Organisation for Applied Scientific Research (TNO), Leiden, Netherlands
| | - Anita van Nieuwkoop
- Department of Metabolic Health Research, Netherlands Organisation for Applied Scientific Research (TNO), Leiden, Netherlands
| | - Martien P. M. Caspers
- Department of Microbiology and Systems Biology, Netherlands Organisation for Applied Scientific Research (TNO), Leiden, Netherlands
| | - Nikolaos Grigoriadis
- Laboratory of Experimental Neurology and Neuroimmunology and the Multiple Sclerosis Center, 2 Department of Neurology, AHEPA University Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Amanda J. Kiliaan
- Department of Medical Imaging, Anatomy, Preclinical Imaging Center (PRIME), Radboud Alzheimer Center, Donders Institute for Brain, Cognition, and Behavior, Radboud University Medical Center, Nijmegen, Netherlands
| | - Frank Baas
- Department of Clinical Genetics, Leiden University Medical Center, Leiden, Netherlands
| | - Iliana Michailidou
- Laboratory of Experimental Neurology and Neuroimmunology and the Multiple Sclerosis Center, 2 Department of Neurology, AHEPA University Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Martine C. Morrison
- Department of Metabolic Health Research, Netherlands Organisation for Applied Scientific Research (TNO), Leiden, Netherlands
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Argunsah AÖ, Israely I. The temporal pattern of synaptic activation determines the longevity of structural plasticity at dendritic spines. iScience 2023; 26:106835. [PMID: 37332599 PMCID: PMC10272476 DOI: 10.1016/j.isci.2023.106835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Revised: 01/18/2023] [Accepted: 05/04/2023] [Indexed: 06/20/2023] Open
Abstract
Learning is thought to involve physiological and structural changes at individual synapses. Synaptic plasticity has predominantly been studied using regular stimulation patterns, but neuronal activity in the brain normally follows a Poisson distribution. We used two-photon imaging and glutamate uncaging to investigate the structural plasticity of single dendritic spines using naturalistic activation patterns sampled from a Poisson distribution. We showed that naturalistic activation patterns elicit structural plasticity that is both NMDAR and protein synthesis-dependent. Furthermore, we uncovered that the longevity of structural plasticity is dependent on the temporal structure of the naturalistic pattern. Finally, we found that during the delivery of the naturalistic activity, spines underwent rapid structural growth that predicted the longevity of plasticity. This was not observed with regularly spaced activity. These data reveal that different temporal organizations of the same number of synaptic stimulations can produce rather distinct short and long-lasting structural plasticity.
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Affiliation(s)
- Ali Özgür Argunsah
- Champalimaud Research, Champalimaud Centre for the Unknown, 1400-038 Lisbon, Portugal
- Laboratory of Neuronal Circuit Assembly, Brain Research Institute (HiFo), University of Zurich, Winterthurerstrasse 190, 8057 Zürich, Switzerland
- Neuroscience Center Zurich (ZNZ), Winterthurerstrasse 190, 8057 Zürich, Switzerland
| | - Inbal Israely
- Champalimaud Research, Champalimaud Centre for the Unknown, 1400-038 Lisbon, Portugal
- Department of Pathology and Cell Biology, Department of Neuroscience, in the Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, Columbia University Medical Center, Vagelos College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA
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Vershinina YS, Krasnov GS, Garbuz DG, Shaposhnikov MV, Fedorova MS, Pudova EA, Katunina IV, Kornev AB, Zemskaya NV, Kudryavtsev AA, Bulavkina EV, Matveeva AA, Ulyasheva NS, Guvatova ZG, Anurov AA, Moskalev AA, Kudryavtseva AV. Transcriptomic Analysis of the Effect of Torin-2 on the Central Nervous System of Drosophila melanogaster. Int J Mol Sci 2023; 24:ijms24109095. [PMID: 37240439 DOI: 10.3390/ijms24109095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 04/24/2023] [Accepted: 05/16/2023] [Indexed: 05/28/2023] Open
Abstract
Torin-2, a synthetic compound, is a highly selective inhibitor of both TORC1 and TORC2 (target of rapamycin) complexes as an alternative to the well-known immunosuppressor, geroprotector, and potential anti-cancer natural compound rapamycin. Torin-2 is effective at hundreds of times lower concentrations and prevents some negative side effects of rapamycin. Moreover, it inhibits the rapamycin-resistant TORC2 complex. In this work, we evaluated transcriptomic changes in D. melanogaster heads induced with lifetime diets containing Torin-2 and suggested possible neuroprotective mechanisms of Torin-2. The analysis included D. melanogaster of three ages (2, 4, and 6 weeks old), separately for males and females. Torin-2, taken at the lowest concentration being tested (0.5 μM per 1 L of nutrient paste), had a slight positive effect on the lifespan of D. melanogaster males (+4% on the average) and no positive effect on females. At the same time, RNA-Seq analysis revealed interesting and previously undiscussed effects of Torin-2, which differed between sexes as well as in flies of different ages. Among the cellular pathways mostly altered by Torin-2 at the gene expression level, we identified immune response, protein folding (heat shock proteins), histone modification, actin cytoskeleton organization, phototransduction and sexual behavior. Additionally, we revealed that Torin-2 predominantly reduced the expression of Srr gene responsible for the conversion of L-serine to D-serine and thus regulating activity of NMDA receptor. Via western blot analysis, we showed than in old males Torin-2 tends to increase the ratio of the active phosphorylated form of ERK, the lowest node of the MAPK cascade, which may play a significant role in neuroprotection. Thus, the complex effect of Torin-2 may be due to the interplay of the immune system, hormonal background, and metabolism. Our work is of interest for further research in the field of NMDA-mediated neurodegeneration.
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Affiliation(s)
- Yulia S Vershinina
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia
| | - George S Krasnov
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia
| | - David G Garbuz
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia
| | | | - Maria S Fedorova
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia
| | - Elena A Pudova
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia
| | - Irina V Katunina
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia
| | - Alexey B Kornev
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia
| | - Nadezhda V Zemskaya
- Institute of Biology, Komi Science Center, Ural Branch of RAS, 167000 Syktyvkar, Russia
| | - Alexander A Kudryavtsev
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia
| | - Elizaveta V Bulavkina
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia
| | - Anna A Matveeva
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia
| | - Natalia S Ulyasheva
- Institute of Biology, Komi Science Center, Ural Branch of RAS, 167000 Syktyvkar, Russia
| | - Zulfiya G Guvatova
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia
| | - Artemiy A Anurov
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia
| | - Alexey A Moskalev
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia
| | - Anna V Kudryavtseva
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia
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Fetterly TL, Catalfio AM, Ferrario CR. Effects of junk-food on food-motivated behavior and NAc glutamate plasticity; insights into the mechanism of NAc calcium-permeable AMPA receptor recruitment. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.16.540977. [PMID: 37292760 PMCID: PMC10245687 DOI: 10.1101/2023.05.16.540977] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
In rats, eating obesogenic diets increase calcium-permeable AMPA receptor (CP-AMPAR) transmission in the nucleus accumbens (NAc) core, and enhances food-motivated behavior. Interestingly these diet-induced alterations in NAc transmission are pronounced in obesity-prone (OP) rats and absent in obesity-resistant (OR) populations. However, effects of diet manipulation on food motivation, and the mechanisms underlying NAc plasticity in OPs is unknown. Using male selectively-bred OP and OR rats, we assessed food-motivated behavior following ad lib access to chow (CH), junk-food (JF), or 10d of JF followed by a return to chow diet (JF-Dep). Behavioral tests included conditioned reinforcement, instrumental responding, and free consumption. Additionally, optogenetic, chemogenetic, and pharmacological approaches were used to examine NAc CP-AMPAR recruitment following diet manipulation and ex vivo treatment of brain slices. Motivation for food was greater in OP than OR rats, as expected. However, JF-Dep only produced enhancements in food-seeking in OP groups, while continuous JF access reduced food-seeking in both OPs and ORs. Reducing excitatory transmission in the NAc was sufficient to recruit CP-AMPARs to synapses in OPs, but not ORs. In OPs, JF-induced increases in CP-AMPARs occurred in mPFC-, but not BLA-to-NAc inputs. Diet differentially affects behavioral and neural plasticity in obesity susceptible populations. We also identify conditions for acute recruitment of NAc CP-AMPARs; these results suggest that synaptic scaling mechanisms contribute to NAc CP-AMPAR recruitment. Overall, this work improves our understanding of how sugary, fatty food consumption interacts with obesity susceptibility to influence food-motivated behavior. It also extends our fundamental understanding of NAc CP-AMPAR recruitment; this has important implications for motivation in the context of obesity as well as drug addiction.
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Affiliation(s)
- Tracy L. Fetterly
- Department of Pharmacology, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Amanda M. Catalfio
- Department of Pharmacology, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Carrie R. Ferrario
- Department of Pharmacology, University of Michigan, Ann Arbor, MI, 48109, USA
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Haas M, Fest T. Final step of B-cell differentiation into plasmablasts; the right time to activate plasma cell PIM2 kinase. Immunol Lett 2023; 258:45-50. [PMID: 37207916 DOI: 10.1016/j.imlet.2023.05.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 05/13/2023] [Accepted: 05/16/2023] [Indexed: 05/21/2023]
Abstract
The differentiation of B cells into antibody-secreting plasma cells is a complex process that involves extensive changes in morphology, lifespan, and cellular metabolism to support the high rates of antibody production. During the final stage of differentiation, B cells undergo significant expansion of their endoplasmic reticulum and mitochondria, which induces cellular stress and may lead to cell death in absence of effective inhibition of the apoptotic pathway. These changes are tightly regulated at transcriptional and epigenetic levels, as well as at post-translational level, with protein modifications playing a critical role in the process of cellular modification and adaptation. Our recent research has highlighted the pivotal role of the serine/threonine kinase PIM2 in B cell differentiation, from commitment stage to plasmablast and maintenance of expression in mature plasma cells. PIM2 has been shown to promote cell cycle progression during the final stage of differentiation and to inhibit Caspase 3 activation, raising the threshold for apoptosis. In this review, we examine the key molecular mechanisms controlled by PIM2 that contribute to plasma cell development and maintenance.
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Affiliation(s)
- Marion Haas
- Université de Rennes 1, INSERM, Établissement Français du Sang de Bretagne, Team B_DEVIL, UMR_S1236, Rennes, France; Laboratoire d'Hématologie, Centre Hospitalier Universitaire, Rennes, France
| | - Thierry Fest
- Université de Rennes 1, INSERM, Établissement Français du Sang de Bretagne, Team B_DEVIL, UMR_S1236, Rennes, France; Laboratoire d'Hématologie, Centre Hospitalier Universitaire, Rennes, France.
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Bauer KE, de Queiroz BR, Kiebler MA, Besse F. RNA granules in neuronal plasticity and disease. Trends Neurosci 2023:S0166-2236(23)00104-2. [PMID: 37202301 DOI: 10.1016/j.tins.2023.04.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Revised: 04/11/2023] [Accepted: 04/16/2023] [Indexed: 05/20/2023]
Abstract
RNA granules are dynamic entities controlling the spatiotemporal distribution and translation of RNA molecules. In neurons, a variety of RNA granules exist both in the soma and in cellular processes. They contain transcripts encoding signaling and synaptic proteins as well as RNA-binding proteins causally linked to several neurological disorders. In this review, we highlight that neuronal RNA granules exhibit properties of biomolecular condensates that are regulated upon maturation and physiological aging and how they are reversibly remodeled in response to neuronal activity to control local protein synthesis and ultimately synaptic plasticity. Moreover, we propose a framework of how neuronal RNA granules mature over time in healthy conditions and how they transition into pathological inclusions in the context of late-onset neurodegenerative diseases.
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Affiliation(s)
- Karl E Bauer
- Biomedical Center (BMC), Department of Anatomy and Cell Biology, Medical Faculty, Ludwig-Maximilians-University, Planegg-Martinsried, Germany
| | - Bruna R de Queiroz
- Université Côte d'Azur, CNRS, Inserm, Institut de Biologie Valrose, Nice, France
| | - Michael A Kiebler
- Biomedical Center (BMC), Department of Anatomy and Cell Biology, Medical Faculty, Ludwig-Maximilians-University, Planegg-Martinsried, Germany.
| | - Florence Besse
- Université Côte d'Azur, CNRS, Inserm, Institut de Biologie Valrose, Nice, France.
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Kim S, Phan S, Shaw TR, Ellisman MH, Veatch SL, Barmada SJ, Pappas SS, Dauer WT. TorsinA is essential for the timing and localization of neuronal nuclear pore complex biogenesis. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.26.538491. [PMID: 37162852 PMCID: PMC10168336 DOI: 10.1101/2023.04.26.538491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Nuclear pore complexes (NPCs) regulate information transfer between the nucleus and cytoplasm. NPC defects are linked to several neurological diseases, but the processes governing NPC biogenesis and spatial organization are poorly understood. Here, we identify a temporal window of strongly upregulated NPC biogenesis during neuronal maturation. We demonstrate that the AAA+ protein torsinA, whose loss of function causes the neurodevelopmental movement disorder DYT-TOR1A (DYT1) dystonia, coordinates NPC spatial organization during this period without impacting total NPC density. Using a new mouse line in which endogenous Nup107 is Halo-Tagged, we find that torsinA is essential for correct localization of NPC formation. In the absence of torsinA, the inner nuclear membrane buds excessively at sites of mislocalized, nascent NPCs, and NPC assembly completion is delayed. Our work implies that NPC spatial organization and number are independently regulated and suggests that torsinA is critical for the normal localization and assembly kinetics of NPCs.
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Affiliation(s)
- Sumin Kim
- Cellular and Molecular Biology Graduate Program, University of Michigan, Ann Arbor, MI
- Department of Neurology, University of Michigan, Ann Arbor, MI
| | - Sébastien Phan
- National Center for Microscopy and Imaging Research, Center for Research on Biological Systems, Department of Neurosciences, School of Medicine, University of California San Diego, La Jolla, CA
| | - Thomas R. Shaw
- Department of Biophysics, University of Michigan, Ann Arbor, MI
| | - Mark H. Ellisman
- National Center for Microscopy and Imaging Research, Center for Research on Biological Systems, Department of Neurosciences, School of Medicine, University of California San Diego, La Jolla, CA
| | - Sarah L. Veatch
- Department of Biophysics, University of Michigan, Ann Arbor, MI
| | - Sami J. Barmada
- Cellular and Molecular Biology Graduate Program, University of Michigan, Ann Arbor, MI
- Department of Neurology, University of Michigan, Ann Arbor, MI
| | - Samuel S. Pappas
- Peter O’Donnell Jr. Brain Institute, UT Southwestern, Dallas, TX
- Department of Neurology, UT Southwestern, Dallas, TX
| | - William T. Dauer
- Peter O’Donnell Jr. Brain Institute, UT Southwestern, Dallas, TX
- Department of Neurology, UT Southwestern, Dallas, TX
- Department of Neuroscience, UT Southwestern, Dallas, TX
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Wang Y, Lin J, Li J, Yan L, Li W, He X, Ma H. Chronic Neuronal Inactivity Utilizes the mTOR-TFEB Pathway to Drive Transcription-Dependent Autophagy for Homeostatic Up-Scaling. J Neurosci 2023; 43:2631-2652. [PMID: 36868861 PMCID: PMC10089247 DOI: 10.1523/jneurosci.0146-23.2023] [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: 01/24/2023] [Revised: 02/16/2023] [Accepted: 02/26/2023] [Indexed: 03/05/2023] Open
Abstract
Activity-dependent changes in protein expression are critical for neuronal plasticity, a fundamental process for the processing and storage of information in the brain. Among the various forms of plasticity, homeostatic synaptic up-scaling is unique in that it is induced primarily by neuronal inactivity. However, precisely how the turnover of synaptic proteins occurs in this homeostatic process remains unclear. Here, we report that chronically inhibiting neuronal activity in primary cortical neurons prepared from embryonic day (E)18 Sprague Dawley rats (both sexes) induces autophagy, thereby regulating key synaptic proteins for up-scaling. Mechanistically, chronic neuronal inactivity causes dephosphorylation of ERK and mTOR, which induces transcription factor EB (TFEB)-mediated cytonuclear signaling and drives transcription-dependent autophagy to regulate αCaMKII and PSD95 during synaptic up-scaling. Together, these findings suggest that mTOR-dependent autophagy, which is often triggered by metabolic stressors such as starvation, is recruited and sustained during neuronal inactivity to maintain synaptic homeostasis, a process that ensures proper brain function and if impaired can cause neuropsychiatric disorders such as autism.SIGNIFICANCE STATEMENT In the mammalian brain, protein turnover is tightly controlled by neuronal activation to ensure key neuronal functions during long-lasting synaptic plasticity. However, a long-standing question is how this process occurs during synaptic up-scaling, a process that requires protein turnover but is induced by neuronal inactivation. Here, we report that mTOR-dependent signaling, which is often triggered by metabolic stressors such as starvation, is "hijacked" by chronic neuronal inactivation, which then serves as a nucleation point for transcription factor EB (TFEB) cytonuclear signaling that drives transcription-dependent autophagy for up-scaling. These results provide the first evidence of a physiological role of mTOR-dependent autophagy in enduing neuronal plasticity, thereby connecting major themes in cell biology and neuroscience via a servo loop that mediates autoregulation in the brain.
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Affiliation(s)
- Yang Wang
- Department of Neurobiology, Affiliated Mental Health Center and Hangzhou Seventh People's Hospital, Zhejiang University School of Medicine, Hangzhou 310058, China
- Liangzhu Laboratory, MOE Frontier Science Center for Brain Science and Brain-machine Integration, State Key Laboratory of Brain-machine Intelligence, Zhejiang University, Hangzhou 311121, China
- National Health Commission of the PRC (NHC) and Chinese Academy of Medical Sciences (CAMS) Key Laboratory of Medical Neurobiology, Zhejiang University, Hangzhou 310058, China
| | - Jingran Lin
- Department of Neurobiology, Affiliated Mental Health Center and Hangzhou Seventh People's Hospital, Zhejiang University School of Medicine, Hangzhou 310058, China
- Liangzhu Laboratory, MOE Frontier Science Center for Brain Science and Brain-machine Integration, State Key Laboratory of Brain-machine Intelligence, Zhejiang University, Hangzhou 311121, China
- National Health Commission of the PRC (NHC) and Chinese Academy of Medical Sciences (CAMS) Key Laboratory of Medical Neurobiology, Zhejiang University, Hangzhou 310058, China
| | - Jiarui Li
- Department of Neurobiology, Affiliated Mental Health Center and Hangzhou Seventh People's Hospital, Zhejiang University School of Medicine, Hangzhou 310058, China
- Liangzhu Laboratory, MOE Frontier Science Center for Brain Science and Brain-machine Integration, State Key Laboratory of Brain-machine Intelligence, Zhejiang University, Hangzhou 311121, China
- National Health Commission of the PRC (NHC) and Chinese Academy of Medical Sciences (CAMS) Key Laboratory of Medical Neurobiology, Zhejiang University, Hangzhou 310058, China
| | - Lu Yan
- Department of Neurobiology, Affiliated Mental Health Center and Hangzhou Seventh People's Hospital, Zhejiang University School of Medicine, Hangzhou 310058, China
- Liangzhu Laboratory, MOE Frontier Science Center for Brain Science and Brain-machine Integration, State Key Laboratory of Brain-machine Intelligence, Zhejiang University, Hangzhou 311121, China
- National Health Commission of the PRC (NHC) and Chinese Academy of Medical Sciences (CAMS) Key Laboratory of Medical Neurobiology, Zhejiang University, Hangzhou 310058, China
| | - Wenwen Li
- Department of Neurobiology, Affiliated Mental Health Center and Hangzhou Seventh People's Hospital, Zhejiang University School of Medicine, Hangzhou 310058, China
- Liangzhu Laboratory, MOE Frontier Science Center for Brain Science and Brain-machine Integration, State Key Laboratory of Brain-machine Intelligence, Zhejiang University, Hangzhou 311121, China
- National Health Commission of the PRC (NHC) and Chinese Academy of Medical Sciences (CAMS) Key Laboratory of Medical Neurobiology, Zhejiang University, Hangzhou 310058, China
| | - Xingzhi He
- Department of Neurobiology, Affiliated Mental Health Center and Hangzhou Seventh People's Hospital, Zhejiang University School of Medicine, Hangzhou 310058, China
- Liangzhu Laboratory, MOE Frontier Science Center for Brain Science and Brain-machine Integration, State Key Laboratory of Brain-machine Intelligence, Zhejiang University, Hangzhou 311121, China
- National Health Commission of the PRC (NHC) and Chinese Academy of Medical Sciences (CAMS) Key Laboratory of Medical Neurobiology, Zhejiang University, Hangzhou 310058, China
| | - Huan Ma
- Department of Neurobiology, Affiliated Mental Health Center and Hangzhou Seventh People's Hospital, Zhejiang University School of Medicine, Hangzhou 310058, China
- Liangzhu Laboratory, MOE Frontier Science Center for Brain Science and Brain-machine Integration, State Key Laboratory of Brain-machine Intelligence, Zhejiang University, Hangzhou 311121, China
- National Health Commission of the PRC (NHC) and Chinese Academy of Medical Sciences (CAMS) Key Laboratory of Medical Neurobiology, Zhejiang University, Hangzhou 310058, China
- Research Units for Emotion and Emotion disorders, Chinese Academy of Medical Sciences, Beijing 100050, China
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Zimbelman AR, Wong B, Murray CH, Wolf ME, Stefanik MT. Dopamine D1 and NMDA receptor co-regulation of protein translation in cultured nucleus accumbens neurons. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.02.535293. [PMID: 37034633 PMCID: PMC10081306 DOI: 10.1101/2023.04.02.535293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/11/2023]
Abstract
Protein translation is essential for some forms of synaptic plasticity. We used nucleus accumbens (NAc) medium spiny neurons (MSN), co-cultured with cortical neurons to restore excitatory synapses, to examine whether dopamine modulates protein translation in NAc MSN. FUNCAT was used to measure translation in MSNs under basal conditions and after disinhibiting excitatory transmission using the GABAA receptor antagonist bicuculline (2 hr). Under basal conditions, translation was not altered by the D1-class receptor (D1R) agonist SKF81297 or the D2-class receptor (D2R) agonist quinpirole. Bicuculline alone robustly increased translation. This was reversed by quinpirole but not SKF81297. It was also reversed by co-incubation with the D1R antagonist SCH23390, but not the D2R antagonist eticlopride, suggesting dopaminergic tone at D1Rs. This was surprising because no dopamine neurons are present. An alternative explanation is that bicuculline activates translation by increasing glutamate tone at NMDA receptors (NMDAR) within D1R/NMDAR heteromers, which have been described in other cell types. Supporting this, immunocytochemistry and proximity ligation assays revealed D1/NMDAR heteromers on NAc cells both in vitro and in vivo. Further, bicuculline's effect was reversed to the same extent by SCH23390 alone, the NMDAR antagonist APV alone, or SCH23390+APV. These results suggest that: 1) excitatory synaptic transmission stimulates translation in NAc MSNs, 2) this is opposed when glutamate activates D1R/NMDAR heteromers, even in the absence of dopamine, and 3) antagonist occupation of D1Rs within the heteromers prevents their activation. Our study is the first to suggest a role for D2 receptors and D1R/NMDAR heteromers in regulating protein translation.
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Affiliation(s)
- Alexa R. Zimbelman
- Department of Psychology and Neuroscience, North Central College, Naperville, IL 60540
| | - Benjamin Wong
- Department of Psychology and Neuroscience, North Central College, Naperville, IL 60540
| | - Conor H. Murray
- Department of Neuroscience, The Chicago Medical School at Rosalind Franklin University of Medicine and Science, North Chicago, IL, 60064
- Present address: Department of Psychiatry and Behavioral Neuroscience, University of Chicago, Chicago, IL
| | - Marina E. Wolf
- Department of Neuroscience, The Chicago Medical School at Rosalind Franklin University of Medicine and Science, North Chicago, IL, 60064
- These authors contributed equally
- Present address: Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, OR 97212
| | - Michael T. Stefanik
- Department of Psychology and Neuroscience, North Central College, Naperville, IL 60540
- Department of Neuroscience, The Chicago Medical School at Rosalind Franklin University of Medicine and Science, North Chicago, IL, 60064
- These authors contributed equally
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Berecki G, Bryson A, Polster T, Petrou S. Biophysical characterization and modelling of SCN1A gain-of-function predicts interneuron hyperexcitability and a predisposition to network instability through homeostatic plasticity. Neurobiol Dis 2023; 179:106059. [PMID: 36868483 DOI: 10.1016/j.nbd.2023.106059] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 02/11/2023] [Accepted: 02/27/2023] [Indexed: 03/05/2023] Open
Abstract
SCN1A gain-of-function variants are associated with early onset developmental and epileptic encephalopathies (DEEs) that possess distinct clinical features compared to Dravet syndrome caused by SCN1A loss-of-function. However, it is unclear how SCN1A gain-of-function may predispose to cortical hyper-excitability and seizures. Here, we first report the clinical features of a patient carrying a de novo SCN1A variant (T162I) associated with neonatal-onset DEE, and then characterize the biophysical properties of T162I and three other SCN1A variants associated with neonatal-onset DEE (I236V) and early infantile DEE (P1345S, R1636Q). In voltage clamp experiments, three variants (T162I, P1345S and R1636Q) exhibited changes in activation and inactivation properties that enhanced window current, consistent with gain-of-function. Dynamic action potential clamp experiments utilising model neurons incorporating Nav1.1. channels supported a gain-of-function mechanism for all four variants. Here, the T162I, I236V, P1345S, and R1636Q variants exhibited higher peak firing rates relative to wild type and the T162I and R1636Q variants produced a hyperpolarized threshold and reduced neuronal rheobase. To explore the impact of these variants upon cortical excitability, we used a spiking network model containing an excitatory pyramidal cell (PC) and parvalbumin positive (PV) interneuron population. SCN1A gain-of-function was modelled by enhancing the excitability of PV interneurons and then incorporating three simple forms of homeostatic plasticity that restored pyramidal cell firing rates. We found that homeostatic plasticity mechanisms exerted differential impact upon network function, with changes to PV-to-PC and PC-to-PC synaptic strength predisposing to network instability. Overall, our findings support a role for SCN1A gain-of-function and inhibitory interneuron hyperexcitability in early onset DEE. We propose a mechanism through which homeostatic plasticity pathways can predispose to pathological excitatory activity and contribute to phenotypic variability in SCN1A disorders.
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Affiliation(s)
- Géza Berecki
- Ion Channels and Disease Group, The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC 3052, Australia.
| | - Alexander Bryson
- Ion Channels and Disease Group, The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC 3052, Australia; Department of Neurology, Austin Health, Heidelberg, VIC 3084, Australia
| | - Tilman Polster
- Krankenhaus Mara, Bethel Epilepsy Centre, Department of Epileptology, Medical School, Bielefeld University, Campus Bielefeld-Bethel, Bielefeld, Germany
| | - Steven Petrou
- Ion Channels and Disease Group, The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC 3052, Australia; Praxis Precision Medicines, Inc., Cambridge, MA 02142, USA; Department of the Florey Institute, University of Melbourne, Parkville, VIC 3050, Australia.
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50
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Reemst K, Shahin H, Shahar OD. Learning and memory formation in zebrafish: Protein dynamics and molecular tools. Front Cell Dev Biol 2023; 11:1120984. [PMID: 36968211 PMCID: PMC10034119 DOI: 10.3389/fcell.2023.1120984] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2022] [Accepted: 02/20/2023] [Indexed: 03/12/2023] Open
Abstract
Research on learning and memory formation at the level of neural networks, as well as at the molecular level, is challenging due to the immense complexity of the brain. The zebrafish as a genetically tractable model organism can overcome many of the current challenges of studying molecular mechanisms of learning and memory formation. Zebrafish have a translucent, smaller and more accessible brain than that of mammals, allowing imaging of the entire brain during behavioral manipulations. Recent years have seen an extensive increase in published brain research describing the use of zebrafish for the study of learning and memory. Nevertheless, due to the complexity of the brain comprising many neural cell types that are difficult to isolate, it has been difficult to elucidate neural networks and molecular mechanisms involved in memory formation in an unbiased manner, even in zebrafish larvae. Therefore, data regarding the identity, location, and intensity of nascent proteins during memory formation is still sparse and our understanding of the molecular networks remains limited, indicating a need for new techniques. Here, we review recent progress in establishing learning paradigms for zebrafish and the development of methods to elucidate neural and molecular networks of learning. We describe various types of learning and highlight directions for future studies, focusing on molecular mechanisms of long-term memory formation and promising state-of-the-art techniques such as cell-type-specific metabolic labeling.
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Affiliation(s)
- Kitty Reemst
- Migal—Galilee Research Institute, Kiryat Shmona, Israel
- Department of Biotechnology, Tel-Hai College, Kiryat Shmona, Israel
| | - Heba Shahin
- Migal—Galilee Research Institute, Kiryat Shmona, Israel
- Department of Biotechnology, Tel-Hai College, Kiryat Shmona, Israel
| | - Or David Shahar
- Migal—Galilee Research Institute, Kiryat Shmona, Israel
- Department of Biotechnology, Tel-Hai College, Kiryat Shmona, Israel
- *Correspondence: Or David Shahar,
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