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Metzbower SR, Levy AD, Dharmasri PA, Anderson MC, Blanpied TA. Distinct SAP102 and PSD-95 Nano-organization Defines Multiple Types of Synaptic Scaffold Protein Domains at Single Synapses. J Neurosci 2024; 44:e1715232024. [PMID: 38777601 DOI: 10.1523/jneurosci.1715-23.2024] [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: 09/10/2023] [Revised: 04/30/2024] [Accepted: 05/05/2024] [Indexed: 05/25/2024] Open
Abstract
MAGUK scaffold proteins play a central role in maintaining and modulating synaptic signaling, providing a framework to retain and position receptors, signaling molecules, and other synaptic components. In particular, the MAGUKs SAP102 and PSD-95 are essential for synaptic function at distinct developmental timepoints and perform both overlapping and unique roles. While their similar structures allow for common binding partners, SAP102 is expressed earlier in synapse development and is required for synaptogenesis, whereas PSD-95 expression peaks later and is associated with synapse maturation. PSD-95 and other key synaptic proteins organize into subsynaptic nanodomains that have a significant impact on synaptic transmission, but the nanoscale organization of SAP102 is unknown. How SAP102 is organized within the synapse, and how it relates spatially to PSD-95 on a nanometer scale, could underlie its unique functions and impact how SAP102 scaffolds synaptic proteins. Here we used DNA-PAINT super-resolution microscopy to measure SAP102 nano-organization and its spatial relationship to PSD-95 at individual synapses in mixed-sex rat cultured neurons. We found that like PSD-95, SAP102 accumulates in high-density subsynaptic nanoclusters (NCs). However, SAP102 NCs were smaller and denser than PSD-95 NCs across development. Additionally, only a subset of SAP102 NCs co-organized with PSD-95, revealing MAGUK nanodomains within individual synapses containing either one or both proteins. These MAGUK nanodomain types had distinct NC properties and were differentially enriched with the presynaptic release protein Munc13-1. This organization into both shared and distinct subsynaptic nanodomains may underlie the ability of SAP102 and PSD-95 to perform both common and unique synaptic functions.
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Affiliation(s)
- Sarah R Metzbower
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland 21201
| | - Aaron D Levy
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland 21201
| | - Poorna A Dharmasri
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland 21201
- Program in Neuroscience, University of Maryland School of Medicine, Baltimore, Maryland 21201
| | - Michael C Anderson
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland 21201
- Program in Neuroscience, University of Maryland School of Medicine, Baltimore, Maryland 21201
| | - Thomas A Blanpied
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland 21201
- Program in Neuroscience, University of Maryland School of Medicine, Baltimore, Maryland 21201
- University of Maryland Medicine Institute for Neuroscience Discovery, University of Maryland School of Medicine, Baltimore, Maryland 21201
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2
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Chapman LR, Ramnarine IVP, Zemke D, Majid A, Bell SM. Gene Expression Studies in Down Syndrome: What Do They Tell Us about Disease Phenotypes? Int J Mol Sci 2024; 25:2968. [PMID: 38474215 DOI: 10.3390/ijms25052968] [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: 02/04/2024] [Revised: 02/27/2024] [Accepted: 02/28/2024] [Indexed: 03/14/2024] Open
Abstract
Down syndrome is a well-studied aneuploidy condition in humans, which is associated with various disease phenotypes including cardiovascular, neurological, haematological and immunological disease processes. This review paper aims to discuss the research conducted on gene expression studies during fetal development. A descriptive review was conducted, encompassing all papers published on the PubMed database between September 1960 and September 2022. We found that in amniotic fluid, certain genes such as COL6A1 and DSCR1 were found to be affected, resulting in phenotypical craniofacial changes. Additionally, other genes such as GSTT1, CLIC6, ITGB2, C21orf67, C21orf86 and RUNX1 were also identified to be affected in the amniotic fluid. In the placenta, dysregulation of genes like MEST, SNF1LK and LOX was observed, which in turn affected nervous system development. In the brain, dysregulation of genes DYRK1A, DNMT3L, DNMT3B, TBX1, olig2 and AQP4 has been shown to contribute to intellectual disability. In the cardiac tissues, dysregulated expression of genes GART, ETS2 and ERG was found to cause abnormalities. Furthermore, dysregulation of XIST, RUNX1, SON, ERG and STAT1 was observed, contributing to myeloproliferative disorders. Understanding the differential expression of genes provides insights into the genetic consequences of DS. A better understanding of these processes could potentially pave the way for the development of genetic and pharmacological therapies.
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Affiliation(s)
- Laura R Chapman
- Sheffield Children's NHS Foundation Trust, Clarkson St, Sheffield S10 2TH, UK
- Sheffield Institute of Translational Neuroscience, University of Sheffield, Glossop Road, Sheffield S10 2GF, UK
| | - Isabela V P Ramnarine
- Sheffield Institute of Translational Neuroscience, University of Sheffield, Glossop Road, Sheffield S10 2GF, UK
| | - Dan Zemke
- Sheffield Institute of Translational Neuroscience, University of Sheffield, Glossop Road, Sheffield S10 2GF, UK
| | - Arshad Majid
- Sheffield Institute of Translational Neuroscience, University of Sheffield, Glossop Road, Sheffield S10 2GF, UK
- Sheffield Teaching Hospitals NHS Foundation Trust, Royal Hallamshire Hospital, Glossop Road, Sheffield S10 2GJ, UK
| | - Simon M Bell
- Sheffield Institute of Translational Neuroscience, University of Sheffield, Glossop Road, Sheffield S10 2GF, UK
- Sheffield Teaching Hospitals NHS Foundation Trust, Royal Hallamshire Hospital, Glossop Road, Sheffield S10 2GJ, UK
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3
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Tollis P, Vitiello E, Migliaccio F, D'Ambra E, Rocchegiani A, Garone MG, Bozzoni I, Rosa A, Carissimo A, Laneve P, Caffarelli E. The long noncoding RNA nHOTAIRM1 is necessary for differentiation and activity of iPSC-derived spinal motor neurons. Cell Death Dis 2023; 14:741. [PMID: 37963881 PMCID: PMC10646148 DOI: 10.1038/s41419-023-06196-y] [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: 04/14/2023] [Revised: 09/19/2023] [Accepted: 09/28/2023] [Indexed: 11/16/2023]
Abstract
The mammalian nervous system is made up of an extraordinary array of diverse cells that form intricate functional connections. The programs underlying cell lineage specification, identity and function of the neuronal subtypes are managed by regulatory proteins and RNAs, which coordinate the succession of steps in a stereotyped temporal order. In the central nervous system (CNS), motor neurons (MNs) are responsible for controlling essential functions such as movement, breathing, and swallowing by integrating signal transmission from the cortex, brainstem, and spinal cord (SC) towards peripheral muscles. A prime role in guiding the progression of progenitor cells towards the MN fate has been largely attributed to protein factors. More recently, the relevance of a class of regulatory RNAs abundantly expressed in the CNS - the long noncoding RNAs (lncRNAs) - has emerged overwhelmingly. LncRNA-driven gene expression control is key to regulating any step of MN differentiation and function, and its derangement profoundly impacts neuronal pathophysiology. Here, we uncover a novel function for the neuronal isoform of HOTAIRM1 (nHOTAIRM1), a lncRNA specifically expressed in the SC. Using a model system that recapitulates spinal MN (spMN) differentiation, we show that nHOTAIRM1 intervenes in the binary cell fate decision between MNs and interneurons, acting as a pro-MN factor. Furthermore, human iPSC-derived spMNs without nHOTAIRM1 display altered neurite outgrowth, with a significant reduction of both branch and junction numbers. Finally, the expression of genes essential for synaptic connectivity and neurotransmission is also profoundly impaired when nHOTAIRM1 is absent in spMNs. Mechanistically, nHOTAIRM1 establishes both direct and indirect interactions with a number of target genes in the cytoplasm, being a novel post-transcriptional regulator of MN biology. Overall, our results indicate that the lncRNA nHOTAIRM1 is essential for the specification of MN identity and the acquisition of proper morphology and synaptic activity of post-mitotic MNs.
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Affiliation(s)
- Paolo Tollis
- Department of Biology and Biotechnologies "C. Darwin", Sapienza University of Rome, Rome, Italy
- Center for Life Nano-& Neuro-Science, Fondazione Istituto Italiano di Tecnologia, Rome, Italy
| | - Erika Vitiello
- Department of Biology and Biotechnologies "C. Darwin", Sapienza University of Rome, Rome, Italy
- Center for Human Technology, Fondazione Istituto Italiano di Tecnologia, Genoa, Italy
| | - Francesco Migliaccio
- Department of Electrical Engineering and Information Technology, University Federico II, Naples, Italy
- Institute for Applied Mathematics "Mauro Picone", CNR, Naples, Italy
| | - Eleonora D'Ambra
- Center for Life Nano-& Neuro-Science, Fondazione Istituto Italiano di Tecnologia, Rome, Italy
| | - Anna Rocchegiani
- Department of Biology and Biotechnologies "C. Darwin", Sapienza University of Rome, Rome, Italy
- Division of Cell and Developmental Biology, Center for Anatomy and Cell Biology, Medical University of Vienna, Vienna, Austria
| | - Maria Giovanna Garone
- Department of Biology and Biotechnologies "C. Darwin", Sapienza University of Rome, Rome, Italy
- The Novo Nordisk Foundation Center for Stem Cell Medicine, reNEW Melbourne, Murdoch Children's Research Institute, Parkville, VIC, 3052, Australia
- Stem Cell Biology Department, Murdoch Children's Research Institute, Parkville, VIC, 3052, Australia
| | - Irene Bozzoni
- Department of Biology and Biotechnologies "C. Darwin", Sapienza University of Rome, Rome, Italy
- Center for Life Nano-& Neuro-Science, Fondazione Istituto Italiano di Tecnologia, Rome, Italy
| | - Alessandro Rosa
- Department of Biology and Biotechnologies "C. Darwin", Sapienza University of Rome, Rome, Italy
- Center for Life Nano-& Neuro-Science, Fondazione Istituto Italiano di Tecnologia, Rome, Italy
| | | | - Pietro Laneve
- Institute of Molecular Biology and Pathology, Rome, CNR, Italy.
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Shen Z, Sun D, Savastano A, Varga SJ, Cima-Omori MS, Becker S, Honigmann A, Zweckstetter M. Multivalent Tau/PSD-95 interactions arrest in vitro condensates and clusters mimicking the postsynaptic density. Nat Commun 2023; 14:6839. [PMID: 37891164 PMCID: PMC10611757 DOI: 10.1038/s41467-023-42295-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Accepted: 10/05/2023] [Indexed: 10/29/2023] Open
Abstract
Alzheimer's disease begins with mild memory loss and slowly destroys memory and thinking. Cognitive impairment in Alzheimer's disease has been associated with the localization of the microtubule-associated protein Tau at the postsynapse. However, the correlation between Tau at the postsynapse and synaptic dysfunction remains unclear. Here, we show that Tau arrests liquid-like droplets formed by the four postsynaptic density proteins PSD-95, GKAP, Shank, Homer in solution, as well as NMDA (N-methyl-D-aspartate)-receptor-associated protein clusters on synthetic membranes. Tau-mediated condensate/cluster arrest critically depends on the binding of multiple interaction motifs of Tau to a canonical GMP-binding pocket in the guanylate kinase domain of PSD-95. We further reveal that competitive binding of a high-affinity phosphorylated peptide to PSD-95 rescues the diffusional dynamics of an NMDA truncated construct, which contains the last five amino acids of the NMDA receptor subunit NR2B fused to the C-terminus of the tetrameric GCN4 coiled-coil domain, in postsynaptic density-like condensates/clusters. Taken together, our findings propose a molecular mechanism where Tau modulates the dynamic properties of the postsynaptic density.
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Affiliation(s)
- Zheng Shen
- German Center for Neurodegenerative Diseases (DZNE), Von-Siebold-Str. 3a, 37075, Göttingen, Germany
| | - Daxiao Sun
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Adriana Savastano
- German Center for Neurodegenerative Diseases (DZNE), Von-Siebold-Str. 3a, 37075, Göttingen, Germany
| | - Sára Joana Varga
- German Center for Neurodegenerative Diseases (DZNE), Von-Siebold-Str. 3a, 37075, Göttingen, Germany
| | - Maria-Sol Cima-Omori
- German Center for Neurodegenerative Diseases (DZNE), Von-Siebold-Str. 3a, 37075, Göttingen, Germany
| | - Stefan Becker
- Max Planck Institute for Multidisciplinary Sciences, Department of NMR-based Structural Biology, Am Fassberg 11, 37077, Göttingen, Germany
| | - Alf Honigmann
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
- Technische Universität Dresden, Biotechnologisches Zentrum (BIOTEC), Dresden, Germany
| | - Markus Zweckstetter
- German Center for Neurodegenerative Diseases (DZNE), Von-Siebold-Str. 3a, 37075, Göttingen, Germany.
- Max Planck Institute for Multidisciplinary Sciences, Department of NMR-based Structural Biology, Am Fassberg 11, 37077, Göttingen, Germany.
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5
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Wang L, Pang K, Zhou L, Cebrián-Silla A, González-Granero S, Wang S, Bi Q, White ML, Ho B, Li J, Li T, Perez Y, Huang EJ, Winkler EA, Paredes MF, Kovner R, Sestan N, Pollen AA, Liu P, Li J, Piao X, García-Verdugo JM, Alvarez-Buylla A, Liu Z, Kriegstein AR. A cross-species proteomic map reveals neoteny of human synapse development. Nature 2023; 622:112-119. [PMID: 37704727 PMCID: PMC10576238 DOI: 10.1038/s41586-023-06542-2] [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: 01/06/2023] [Accepted: 08/15/2023] [Indexed: 09/15/2023]
Abstract
The molecular mechanisms and evolutionary changes accompanying synapse development are still poorly understood1,2. Here we generate a cross-species proteomic map of synapse development in the human, macaque and mouse neocortex. By tracking the changes of more than 1,000 postsynaptic density (PSD) proteins from midgestation to young adulthood, we find that PSD maturation in humans separates into three major phases that are dominated by distinct pathways. Cross-species comparisons reveal that human PSDs mature about two to three times slower than those of other species and contain higher levels of Rho guanine nucleotide exchange factors (RhoGEFs) in the perinatal period. Enhancement of RhoGEF signalling in human neurons delays morphological maturation of dendritic spines and functional maturation of synapses, potentially contributing to the neotenic traits of human brain development. In addition, PSD proteins can be divided into four modules that exert stage- and cell-type-specific functions, possibly explaining their differential associations with cognitive functions and diseases. Our proteomic map of synapse development provides a blueprint for studying the molecular basis and evolutionary changes of synapse maturation.
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Affiliation(s)
- Li Wang
- The Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California San Francisco, San Francisco, CA, USA.
- Department of Neurology, University of California San Francisco, San Francisco, CA, USA.
| | - Kaifang Pang
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, TX, USA
- Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA
| | - Li Zhou
- The Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California San Francisco, San Francisco, CA, USA
- Department of Neurology, University of California San Francisco, San Francisco, CA, USA
| | - Arantxa Cebrián-Silla
- The Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California San Francisco, San Francisco, CA, USA
- Department of Neurological Surgery, University of California San Francisco, San Francisco, CA, USA
| | - Susana González-Granero
- Laboratory of Comparative Neurobiology, Cavanilles Institute of Biodiversity and Evolutionary Biology, University of Valencia and CIBERNED, Valencia, Spain
| | - Shaohui Wang
- The Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California San Francisco, San Francisco, CA, USA
- Department of Neurology, University of California San Francisco, San Francisco, CA, USA
| | - Qiuli Bi
- The Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California San Francisco, San Francisco, CA, USA
- Department of Neurology, University of California San Francisco, San Francisco, CA, USA
| | - Matthew L White
- The Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California San Francisco, San Francisco, CA, USA
- Department of Neurology, University of California San Francisco, San Francisco, CA, USA
| | - Brandon Ho
- The Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California San Francisco, San Francisco, CA, USA
- Department of Neurology, University of California San Francisco, San Francisco, CA, USA
| | - Jiani Li
- Gilead Sciences, Foster City, CA, USA
| | - Tao Li
- The Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California San Francisco, San Francisco, CA, USA
| | - Yonatan Perez
- The Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California San Francisco, San Francisco, CA, USA
- Department of Neurology, University of California San Francisco, San Francisco, CA, USA
| | - Eric J Huang
- Department of Pathology, University of California San Francisco, San Francisco, CA, USA
| | - Ethan A Winkler
- Department of Neurological Surgery, University of California San Francisco, San Francisco, CA, USA
| | - Mercedes F Paredes
- The Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California San Francisco, San Francisco, CA, USA
- Department of Neurology, University of California San Francisco, San Francisco, CA, USA
| | - Rothem Kovner
- Department of Neuroscience, Yale School of Medicine, Yale University, New Haven, CT, USA
| | - Nenad Sestan
- Department of Neuroscience, Yale School of Medicine, Yale University, New Haven, CT, USA
| | - Alex A Pollen
- The Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California San Francisco, San Francisco, CA, USA
- Department of Neurology, University of California San Francisco, San Francisco, CA, USA
| | - Pengyuan Liu
- Department of Chemistry, University of Massachusetts Lowell, Lowell, MA, USA
| | - Jingjing Li
- The Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California San Francisco, San Francisco, CA, USA
- Department of Neurology, University of California San Francisco, San Francisco, CA, USA
| | - Xianhua Piao
- The Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California San Francisco, San Francisco, CA, USA
- Division of Neonatology, Department of Pediatrics, University of California San Francisco, San Francisco, CA, USA
- Newborn Brain Research Institute, University of California San Francisco, San Francisco, CA, USA
| | - José Manuel García-Verdugo
- Laboratory of Comparative Neurobiology, Cavanilles Institute of Biodiversity and Evolutionary Biology, University of Valencia and CIBERNED, Valencia, Spain
| | - Arturo Alvarez-Buylla
- The Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California San Francisco, San Francisco, CA, USA
- Department of Neurological Surgery, University of California San Francisco, San Francisco, CA, USA
| | - Zhandong Liu
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, TX, USA
- Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA
| | - Arnold R Kriegstein
- The Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California San Francisco, San Francisco, CA, USA.
- Department of Neurology, University of California San Francisco, San Francisco, CA, USA.
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6
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Zhu ML, Zhang J, Guo LJ, Yue RZ, Li SS, Cui BY, Guo S, Niu QQ, Yu YN, Wang HH, Yang L, Yin YL, Wang SX, Zhan HQ, Gao ZT, Li P. Amorphous selenium inhibits oxidative stress injury of neurons in vascular dementia rats by activating NMDAR pathway. Eur J Pharmacol 2023; 955:175874. [PMID: 37394029 DOI: 10.1016/j.ejphar.2023.175874] [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: 04/27/2023] [Revised: 06/11/2023] [Accepted: 06/20/2023] [Indexed: 07/04/2023]
Abstract
Vascular dementia (VD) is one of the most common causes of dementia, taking account for about 20% of all cases. Although studies have found that selenium supplementation can improve the cognitive ability of Alzheimer's patients, there is currently no research on the cognitive impairment caused by VD. This study aimed to investigate the role and mechanism of Amorphous selenium nanodots (A SeNDs) in the prevention of VD. The bilateral common carotid artery occlusion (BCCAO) method was used to establish a VD model. The neuroprotective effect of A SeNDs was evaluated by Morris water maze, Transcranial Doppler TCD, hematoxylin-eosin (HE) staining, Neuron-specific nuclear protein (Neu N) staining and Golgi staining. Detect the expression levels of oxidative stress and Calcium-calmodulin dependent protein kinase II (CaMK II), N-methyl-D-aspartate receptor subunit NR2A, and postsynaptic dense protein 95 (PSD95). Finally, measure the concentration of calcium ions in neuronal cells. The results showed that A SeNDs could significantly improve the learning and memory ability of VD rats, restore the posterior arterial blood flow of the brain, improve the neuronal morphology and dendritic remodeling of pyramidal cells in hippocampal CA1 area, reduce the level of oxidative stress in VD rats, increase the expression of NR2A, PSD95, CaMK II proteins and reduce intracellular calcium ion concentration, but the addition of selective NR2A antagonist NVP-AAMO77 eliminated these benefits. It suggests that A SeNDs may improve cognitive dysfunction in vascular dementia rats by regulating the NMDAR pathway.
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Affiliation(s)
- Mo-Li Zhu
- Henan International Joint Laboratory of Cardiovascular Remodeling and Drug Intervention, Sino-UK Joint Laboratory of Brain Function and Injury of Henan Province, College of Pharmacy, School of Basic Medical Sciences, Xinxiang Medical University, Xinxiang, 453003, China
| | - Jie Zhang
- Henan International Joint Laboratory of Cardiovascular Remodeling and Drug Intervention, Sino-UK Joint Laboratory of Brain Function and Injury of Henan Province, College of Pharmacy, School of Basic Medical Sciences, Xinxiang Medical University, Xinxiang, 453003, China
| | - Li-Juan Guo
- Department of Oncology, First Affiliated Hospital of Xinxiang Medical University, Xinxiang, 453119, China
| | - Rui-Zhu Yue
- Henan International Joint Laboratory of Cardiovascular Remodeling and Drug Intervention, Sino-UK Joint Laboratory of Brain Function and Injury of Henan Province, College of Pharmacy, School of Basic Medical Sciences, Xinxiang Medical University, Xinxiang, 453003, China
| | - Shan-Shan Li
- Henan International Joint Laboratory of Cardiovascular Remodeling and Drug Intervention, Sino-UK Joint Laboratory of Brain Function and Injury of Henan Province, College of Pharmacy, School of Basic Medical Sciences, Xinxiang Medical University, Xinxiang, 453003, China
| | - Bao-Yue Cui
- Henan International Joint Laboratory of Cardiovascular Remodeling and Drug Intervention, Sino-UK Joint Laboratory of Brain Function and Injury of Henan Province, College of Pharmacy, School of Basic Medical Sciences, Xinxiang Medical University, Xinxiang, 453003, China
| | - Shuang Guo
- Hubei Key Laboratory of Diabetes and Angiopathy, Hubei University of Science and Technology, Xianning, 437100, China
| | - Qian-Qian Niu
- Henan International Joint Laboratory of Cardiovascular Remodeling and Drug Intervention, Sino-UK Joint Laboratory of Brain Function and Injury of Henan Province, College of Pharmacy, School of Basic Medical Sciences, Xinxiang Medical University, Xinxiang, 453003, China
| | - Ya-Nan Yu
- Henan International Joint Laboratory of Cardiovascular Remodeling and Drug Intervention, Sino-UK Joint Laboratory of Brain Function and Injury of Henan Province, College of Pharmacy, School of Basic Medical Sciences, Xinxiang Medical University, Xinxiang, 453003, China
| | - Huan-Huan Wang
- Henan International Joint Laboratory of Cardiovascular Remodeling and Drug Intervention, Sino-UK Joint Laboratory of Brain Function and Injury of Henan Province, College of Pharmacy, School of Basic Medical Sciences, Xinxiang Medical University, Xinxiang, 453003, China
| | - Lin Yang
- Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine Chemicals, Key Laboratory of Green Chemical Media and Reactions, Ministry of Education, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, 453007, China
| | - Ya-Ling Yin
- Henan International Joint Laboratory of Cardiovascular Remodeling and Drug Intervention, Sino-UK Joint Laboratory of Brain Function and Injury of Henan Province, College of Pharmacy, School of Basic Medical Sciences, Xinxiang Medical University, Xinxiang, 453003, China.
| | - Shuang-Xi Wang
- Henan International Joint Laboratory of Cardiovascular Remodeling and Drug Intervention, Sino-UK Joint Laboratory of Brain Function and Injury of Henan Province, College of Pharmacy, School of Basic Medical Sciences, Xinxiang Medical University, Xinxiang, 453003, China.
| | - He-Qin Zhan
- Henan International Joint Laboratory of Cardiovascular Remodeling and Drug Intervention, Sino-UK Joint Laboratory of Brain Function and Injury of Henan Province, College of Pharmacy, School of Basic Medical Sciences, Xinxiang Medical University, Xinxiang, 453003, China.
| | - Zhi-Tao Gao
- School of Laboratory Medicine, Xinxiang Medical University, Xinxiang, 453003, China.
| | - Peng Li
- Henan International Joint Laboratory of Cardiovascular Remodeling and Drug Intervention, Sino-UK Joint Laboratory of Brain Function and Injury of Henan Province, College of Pharmacy, School of Basic Medical Sciences, Xinxiang Medical University, Xinxiang, 453003, China; Hubei Key Laboratory of Diabetes and Angiopathy, Hubei University of Science and Technology, Xianning, 437100, China.
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7
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Gromova KV, Thies E, Janiesch PC, Lützenkirchen FP, Zhu Y, Stajano D, Dürst CD, Schweizer M, Konietzny A, Mikhaylova M, Gee CE, Kneussel M. The kinesin Kif21b binds myosin Va and mediates changes in actin dynamics underlying homeostatic synaptic downscaling. Cell Rep 2023; 42:112743. [PMID: 37418322 DOI: 10.1016/j.celrep.2023.112743] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 05/15/2023] [Accepted: 06/19/2023] [Indexed: 07/09/2023] Open
Abstract
Homeostatic synaptic plasticity adjusts the strength of synapses to restrain neuronal activity within a physiological range. Postsynaptic guanylate kinase-associated protein (GKAP) controls the bidirectional synaptic scaling of AMPA receptors (AMPARs); however, mechanisms by which chronic activity triggers cytoskeletal remodeling to downscale synaptic transmission are barely understood. Here, we report that the microtubule-dependent kinesin motor Kif21b binds GKAP and likewise is located in dendritic spines in a myosin Va- and neuronal-activity-dependent manner. Kif21b depletion unexpectedly alters actin dynamics in spines, and adaptation of actin turnover following chronic activity is lost in Kif21b-knockout neurons. Consistent with a role of the kinesin in regulating actin dynamics, Kif21b overexpression promotes actin polymerization. Moreover, Kif21b controls GKAP removal from spines and the decrease of GluA2-containing AMPARs from the neuronal surface, thereby inducing homeostatic synaptic downscaling. Our data highlight a critical role of Kif21b at the synaptic actin cytoskeleton underlying homeostatic scaling of neuronal firing.
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Affiliation(s)
- Kira V Gromova
- Department of Molecular Neurogenetics, Center for Molecular Neurobiology, ZMNH, University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany.
| | - Edda Thies
- Department of Molecular Neurogenetics, Center for Molecular Neurobiology, ZMNH, University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Philipp C Janiesch
- Department of Molecular Neurogenetics, Center for Molecular Neurobiology, ZMNH, University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Felix P Lützenkirchen
- Department of Molecular Neurogenetics, Center for Molecular Neurobiology, ZMNH, University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Yipeng Zhu
- Department of Molecular Neurogenetics, Center for Molecular Neurobiology, ZMNH, University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Daniele Stajano
- Department of Molecular Neurogenetics, Center for Molecular Neurobiology, ZMNH, University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Céline D Dürst
- Department of Synaptic Physiology, Center for Molecular Neurobiology, ZMNH, University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Michaela Schweizer
- Core Facility Morphology, Center for Molecular Neurobiology, ZMNH, University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Anja Konietzny
- RG Neuronal Protein Transport, Center for Molecular Neurobiology, ZMNH, University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Marina Mikhaylova
- RG Neuronal Protein Transport, Center for Molecular Neurobiology, ZMNH, University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany; RG Optobiology, Institute of Biology, Humboldt Universität zu Berlin, 10099 Berlin, Germany
| | - Christine E Gee
- Department of Synaptic Physiology, Center for Molecular Neurobiology, ZMNH, University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Matthias Kneussel
- Department of Molecular Neurogenetics, Center for Molecular Neurobiology, ZMNH, University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany; Hamburg Center of Neuroscience, HCNS, University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany.
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8
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Shaffery JP, Marks GA. Howard P. Roffwarg: sleep pioneer, legend, and ontogenetic hypothesis author. SLEEP ADVANCES : A JOURNAL OF THE SLEEP RESEARCH SOCIETY 2023; 4:zpad004. [PMID: 37193292 PMCID: PMC10108642 DOI: 10.1093/sleepadvances/zpad004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 12/15/2022] [Indexed: 05/18/2023]
Abstract
Narrated in this article are accounts of the many contributions Howard P. Roffwarg, MD, made to the field of sleep research and sleep medicine across his entire professional career as a student, a mentor, a leader in the Sleep Research Society, a sleep medicine clinician, and a scientist who performed experimental investigations in humans and animals. Dr Roffwarg was the originator of what is known as the "Ontogenetic Hypothesis" of sleep. His research over many years on physiology has contributed greatly to much of the experimental support substantiating a role for rapid eye-movement sleep (REMS) in the early development of the brain. Though much is still unknown, the Ontogenetic Hypothesis, still to this day, inspires many neuroscientists in their investigations. These studies have demonstrated roles for both REMS and NREMS in development as well as on brain function throughout his life span. Dr Howard P. Roffwarg, is one of the legends in the field of sleep research.
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Affiliation(s)
- James P Shaffery
- Department of Psychiatry and Human Behavior, University of Mississippi, Jackson, MS 39216-4505, USA
| | - Gerald A Marks
- Department of Psychiatry, University of Texas Southwestern, Dallas, TX 75390, USA
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9
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Benske TM, Mu TW, Wang YJ. Protein quality control of N-methyl-D-aspartate receptors. Front Cell Neurosci 2022; 16:907560. [PMID: 35936491 PMCID: PMC9352929 DOI: 10.3389/fncel.2022.907560] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Accepted: 06/29/2022] [Indexed: 12/23/2022] Open
Abstract
N-methyl-D-aspartate receptors (NMDARs) are glutamate-gated cation channels that mediate excitatory neurotransmission and are critical for synaptic development and plasticity in the mammalian central nervous system (CNS). Functional NMDARs typically form via the heterotetrameric assembly of GluN1 and GluN2 subunits. Variants within GRIN genes are implicated in various neurodevelopmental and neuropsychiatric disorders. Due to the significance of NMDAR subunit composition for regional and developmental signaling at synapses, properly folded receptors must reach the plasma membrane for their function. This review focuses on the protein quality control of NMDARs. Specifically, we review the quality control mechanisms that ensure receptors are correctly folded and assembled within the endoplasmic reticulum (ER) and trafficked to the plasma membrane. Further, we discuss disease-associated variants that have shown disrupted NMDAR surface expression and function. Finally, we discuss potential targeted pharmacological and therapeutic approaches to ameliorate disease phenotypes by enhancing the expression and surface trafficking of subunits harboring disease-associated variants, thereby increasing their incorporation into functional receptors.
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Affiliation(s)
| | - Ting-Wei Mu
- Department of Physiology and Biophysics, School of Medicine, Case Western Reserve University, Cleveland, OH, United States
| | - Ya-Juan Wang
- Department of Physiology and Biophysics, School of Medicine, Case Western Reserve University, Cleveland, OH, United States
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10
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Feng Z, Jia B, Zhang M. Liquid-Liquid Phase Separation in Biology: Specific Stoichiometric Molecular Interactions vs Promiscuous Interactions Mediated by Disordered Sequences. Biochemistry 2021; 60:2397-2406. [PMID: 34291921 DOI: 10.1021/acs.biochem.1c00376] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Extensive studies in the past few years have shown that nonmembrane bound organelles are likely assembled via liquid-liquid phase separation (LLPS), a process that is driven by multivalent protein-protein and/or protein-nucleic acid interactions. Both stoichiometric molecular interactions and intrinsically disordered region (IDR)-driven interactions can promote the assembly of membraneless organelles, and the field is currently dominated by IDR-driven biological condensate formation. Here we discuss recent studies that demonstrate the importance of specific biomolecular interactions for functions of diverse physiological condensates. We suggest that phase separation based on combinations of specific interactions and promiscuous IDR-driven interactions is likely a general feature of biological condensation under physiological conditions.
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Affiliation(s)
- Zhe Feng
- Division of Life Science, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong China.,School of Life Sciences, Fudan University, Shanghai 200433, China
| | - Bowen Jia
- Division of Life Science, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong China
| | - Mingjie Zhang
- School of Life Sciences, Southern University of Science and Technology, Shenzhen 518055, China
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11
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The importance of ultrastructural analysis of memory. Brain Res Bull 2021; 173:28-36. [PMID: 33984429 DOI: 10.1016/j.brainresbull.2021.04.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 04/19/2021] [Accepted: 04/22/2021] [Indexed: 11/22/2022]
Abstract
Plasticity of glutamatergic synapses in the hippocampus is believed to underlie learning and memory processes. Surprisingly, very few studies report long-lasting structural changes of synapses induced by behavioral training. It remains, therefore, unclear which synaptic changes in the hippocampus contribute to memory storage. Here, we systematically compare how long-term potentiation of synaptic transmission (LTP) (a primary form of synaptic plasticity and cellular model of memory) and behavioral training affect hippocampal glutamatergic synapses at the ultrastructural level enabled by electron microscopy. The review of the literature indicates that while LTP induces growth of dendritic spines and post-synaptic densities (PSD), that represent postsynaptic part of a glutamatergic synapse, after behavioral training there is transient (< 6 h) synaptogenesis and long-lasting (> 24 h) increase in PSD volume (without a significant change of dendritic spine volume), indicating that training-induced PSD growth may reflect long-term enhancement of synaptic functions. Additionally, formation of multi-innervated spines (MIS), is associated with long-term memory in aged mice and LTP-deficient mutant mice. Since volume of PSD, as well as atypical synapses, can be reliably observed only with electron microscopy, we argue that the ultrastructural level of analysis is required to reveal synaptic changes that are associated with long-term storage of information in the brain.
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12
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Quach TT, Stratton HJ, Khanna R, Kolattukudy PE, Honnorat J, Meyer K, Duchemin AM. Intellectual disability: dendritic anomalies and emerging genetic perspectives. Acta Neuropathol 2021; 141:139-158. [PMID: 33226471 PMCID: PMC7855540 DOI: 10.1007/s00401-020-02244-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 11/04/2020] [Accepted: 11/05/2020] [Indexed: 12/12/2022]
Abstract
Intellectual disability (ID) corresponds to several neurodevelopmental disorders of heterogeneous origin in which cognitive deficits are commonly associated with abnormalities of dendrites and dendritic spines. These histological changes in the brain serve as a proxy for underlying deficits in neuronal network connectivity, mostly a result of genetic factors. Historically, chromosomal abnormalities have been reported by conventional karyotyping, targeted fluorescence in situ hybridization (FISH), and chromosomal microarray analysis. More recently, cytogenomic mapping, whole-exome sequencing, and bioinformatic mining have led to the identification of novel candidate genes, including genes involved in neuritogenesis, dendrite maintenance, and synaptic plasticity. Greater understanding of the roles of these putative ID genes and their functional interactions might boost investigations into determining the plausible link between cellular and behavioral alterations as well as the mechanisms contributing to the cognitive impairment observed in ID. Genetic data combined with histological abnormalities, clinical presentation, and transgenic animal models provide support for the primacy of dysregulation in dendrite structure and function as the basis for the cognitive deficits observed in ID. In this review, we highlight the importance of dendrite pathophysiology in the etiologies of four prototypical ID syndromes, namely Down Syndrome (DS), Rett Syndrome (RTT), Digeorge Syndrome (DGS) and Fragile X Syndrome (FXS). Clinical characteristics of ID have also been reported in individuals with deletions in the long arm of chromosome 10 (the q26.2/q26.3), a region containing the gene for the collapsin response mediator protein 3 (CRMP3), also known as dihydropyrimidinase-related protein-4 (DRP-4, DPYSL4), which is involved in dendritogenesis. Following a discussion of clinical and genetic findings in these syndromes and their preclinical animal models, we lionize CRMP3/DPYSL4 as a novel candidate gene for ID that may be ripe for therapeutic intervention.
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Affiliation(s)
- Tam T Quach
- Institute for Behavioral Medicine Research, Wexner Medical Center, The Ohio State University, Columbus, OH, 43210, USA
- INSERM U1217/CNRS, UMR5310, Université de Lyon, Université Claude Bernard Lyon 1, Lyon, France
| | | | - Rajesh Khanna
- Department of Pharmacology, University of Arizona, Tucson, AZ, 85724, USA
| | | | - Jérome Honnorat
- INSERM U1217/CNRS, UMR5310, Université de Lyon, Université Claude Bernard Lyon 1, Lyon, France
- French Reference Center on Paraneoplastic Neurological Syndromes and Autoimmune Encephalitis, Hospices Civils de Lyon, Lyon, France
- SynatAc Team, Institut NeuroMyoGène, Lyon, France
| | - Kathrin Meyer
- The Research Institute of Nationwide Children Hospital, Columbus, OH, 43205, USA
- Department of Pediatric, The Ohio State University, Columbus, OH, 43210, USA
| | - Anne-Marie Duchemin
- Department of Psychiatry and Behavioral Health, The Ohio State University, Columbus, OH, 43210, USA.
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13
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Warnet XL, Bakke Krog H, Sevillano-Quispe OG, Poulsen H, Kjaergaard M. The C-terminal domains of the NMDA receptor: How intrinsically disordered tails affect signalling, plasticity and disease. Eur J Neurosci 2020; 54:6713-6739. [PMID: 32464691 DOI: 10.1111/ejn.14842] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Revised: 04/16/2020] [Accepted: 05/18/2020] [Indexed: 01/14/2023]
Abstract
NMDA receptors are part of the ionotropic glutamate receptor family, and are crucial for neurotransmission and memory. At the cellular level, the effects of activating these receptors include long-term potentiation (LTP) or depression (LTD). The NMDA receptor is a stringently gated cation channel permeable to Ca2+ , and it shares the molecular architecture of a tetrameric ligand-gated ion channel with the other family members. Its subunits, however, have uniquely long cytoplasmic C-terminal domains (CTDs). While the molecular gymnastics of the extracellular domains have been described in exquisite detail, much less is known about the structure and function of these CTDs. The CTDs vary dramatically in length and sequence between receptor subunits, but they all have a composition characteristic of intrinsically disordered proteins. The CTDs affect channel properties, trafficking and downstream signalling output from the receptor, and these functions are regulated by alternative splicing, protein-protein interactions, and post-translational modifications such as phosphorylation and palmitoylation. Here, we review the roles of the CTDs in synaptic plasticity with a focus on biochemical mechanisms. In total, the CTDs play a multifaceted role as a modifier of channel function, a regulator of cellular location and abundance, and signalling scaffold control the downstream signalling output.
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Affiliation(s)
- Xavier L Warnet
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark.,The Danish Research Institute for Translational Neuroscience (DANDRITE), Aarhus University, Aarhus, Denmark.,The Center for Proteins in Memory (PROMEMO), Aarhus University, Aarhus, Denmark
| | - Helle Bakke Krog
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark.,The Danish Research Institute for Translational Neuroscience (DANDRITE), Aarhus University, Aarhus, Denmark.,The Center for Proteins in Memory (PROMEMO), Aarhus University, Aarhus, Denmark
| | - Oscar G Sevillano-Quispe
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark.,The Danish Research Institute for Translational Neuroscience (DANDRITE), Aarhus University, Aarhus, Denmark.,The Center for Proteins in Memory (PROMEMO), Aarhus University, Aarhus, Denmark
| | - Hanne Poulsen
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark.,The Danish Research Institute for Translational Neuroscience (DANDRITE), Aarhus University, Aarhus, Denmark.,The Center for Proteins in Memory (PROMEMO), Aarhus University, Aarhus, Denmark
| | - Magnus Kjaergaard
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark.,The Danish Research Institute for Translational Neuroscience (DANDRITE), Aarhus University, Aarhus, Denmark.,The Center for Proteins in Memory (PROMEMO), Aarhus University, Aarhus, Denmark
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14
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Investigation of GluA1 and GluA2 AMPA receptor subtype distribution in the hippocampus and anterior cingulate cortex of Long Evans rats during development. IBRO Rep 2020; 8:91-100. [PMID: 32300670 PMCID: PMC7152689 DOI: 10.1016/j.ibror.2020.03.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Accepted: 03/22/2020] [Indexed: 11/21/2022] Open
Abstract
Preadolescent development is characterized by a reorganization of connectivity within and between brain regions that coincides with the emergence of complex behaviors. During the preadolescent period, the rodent hippocampus and regions of the frontal cortex are remodelled as the brain strengthens active connections and eliminates others. In the developing and mature brain, changes in the properties of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPAr)-mediated synaptic responses contribute to experience-dependent changes in neural organization and function. AMPAr are made up of 4 subunits, of which GluA1 and GluA2 have been shown to play the most prominent role in functional plasticity. In this study, we sought to determine whether levels of these two subunits changed during the course of pre-adolescent development in the hippocampus and anterior cingulate cortex (ACC). To investigate the developmental changes in GluA1 and GluA2 AMPAr subunits, Western blotting and immunohistochemistry were performed on the ACC and hippocampus from P18 - P30 and compared to adult (P50) levels and distribution. Within the hippocampus, protein levels of GluA1 and GluA2 peaked around P26-30 whereby localized staining in the dentate gyrus reflected this pattern. GluA1 and GluA2 levels within the ACC showed little variation during this developmental period. These results indicate that changes in AMPAr subunits within the hippocampus coincide with developmental modifications that underlie the shift from juvenile- to adult-like capabilities. However, changes in AMPAr distribution in the ACC might not mediate changes that reflect preadolescent developmental shifts.
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15
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Neuropathophysiology of Lysosomal Storage Diseases: Synaptic Dysfunction as a Starting Point for Disease Progression. J Clin Med 2020; 9:jcm9030616. [PMID: 32106459 PMCID: PMC7141115 DOI: 10.3390/jcm9030616] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 02/21/2020] [Accepted: 02/21/2020] [Indexed: 12/11/2022] Open
Abstract
About two thirds of the patients affected with lysosomal storage diseases (LSD) experience neurological manifestations, such as developmental delay, seizures, or psychiatric problems. In order to develop efficient therapies, it is crucial to understand the neuropathophysiology underlying these symptoms. How exactly lysosomal storage affects biogenesis and function of neurons is still under investigation however recent research highlights a substantial role played by synaptic defects, such as alterations in synaptic spines, synaptic proteins, postsynaptic densities, and synaptic vesicles that might lead to functional impairments in synaptic transmission and neurodegeneration, finally culminating in massive neuronal death and manifestation of cognitive symptoms. Unveiling how the synaptic components are affected in neurological LSD will thus enable a better understanding of the complexity of disease progression as well as identify crucial targets of therapeutic relevance and optimal time windows for targeted intervention.
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16
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Abstract
Emerging evidence indicates that liquid-liquid phase separation, the formation of a condensed molecular assembly within another diluted aqueous solution, is a means for cells to organize highly condensed biological assemblies (also known as biological condensates or membraneless compartments) with very broad functions and regulatory properties in different subcellular regions. Molecular machineries dictating synaptic transmissions in both presynaptic boutons and postsynaptic densities of neuronal synapses may be such biological condensates. Here we review recent developments showing how phase separation can build dense synaptic molecular clusters, highlight unique features of such condensed clusters in the context of synaptic development and signaling, discuss how aberrant phase-separation-mediated synaptic assembly formation may contribute to dysfunctional signaling in psychiatric disorders, and present some challenges and opportunities of phase separation in synaptic biology.
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17
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Translating preclinical findings in clinically relevant new antipsychotic targets: focus on the glutamatergic postsynaptic density. Implications for treatment resistant schizophrenia. Neurosci Biobehav Rev 2019; 107:795-827. [DOI: 10.1016/j.neubiorev.2019.08.019] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2019] [Revised: 07/20/2019] [Accepted: 08/22/2019] [Indexed: 02/07/2023]
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18
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Cuentas-Condori A, Mulcahy B, He S, Palumbos S, Zhen M, Miller DM. C. elegans neurons have functional dendritic spines. eLife 2019; 8:e47918. [PMID: 31584430 PMCID: PMC6802951 DOI: 10.7554/elife.47918] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Accepted: 10/03/2019] [Indexed: 12/15/2022] Open
Abstract
Dendritic spines are specialized postsynaptic structures that transduce presynaptic signals, are regulated by neural activity and correlated with learning and memory. Most studies of spine function have focused on the mammalian nervous system. However, spine-like protrusions have been reported in C. elegans (Philbrook et al., 2018), suggesting that the experimental advantages of smaller model organisms could be exploited to study the biology of dendritic spines. Here, we used super-resolution microscopy, electron microscopy, live-cell imaging and genetics to show that C. elegans motor neurons have functional dendritic spines that: (1) are structurally defined by a dynamic actin cytoskeleton; (2) appose presynaptic dense projections; (3) localize ER and ribosomes; (4) display calcium transients triggered by presynaptic activity and propagated by internal Ca++ stores; (5) respond to activity-dependent signals that regulate spine density. These studies provide a solid foundation for a new experimental paradigm that exploits the power of C. elegans genetics and live-cell imaging for fundamental studies of dendritic spine morphogenesis and function.
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Affiliation(s)
| | - Ben Mulcahy
- Lunenfeld-Tanenbaum Research InstituteUniversity of TorontoTorontoCanada
| | - Siwei He
- Neuroscience ProgramVanderbilt UniversityNashvilleUnited States
| | - Sierra Palumbos
- Neuroscience ProgramVanderbilt UniversityNashvilleUnited States
| | - Mei Zhen
- Lunenfeld-Tanenbaum Research InstituteUniversity of TorontoTorontoCanada
| | - David M Miller
- Department of Cell and Developmental BiologyVanderbilt UniversityNashvilleUnited States
- Neuroscience ProgramVanderbilt UniversityNashvilleUnited States
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19
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Ambroziak W, Fourie C, Montgomery JM. SAP97-mediated rescue of NMDA receptor surface distribution in a neuronal model of Huntington's disease. Hippocampus 2019; 28:707-723. [PMID: 30067285 DOI: 10.1002/hipo.22995] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Revised: 04/22/2018] [Accepted: 05/29/2018] [Indexed: 01/10/2023]
Abstract
Huntington's disease (HD) is a genetic neurodegenerative disorder caused by an expansion of the CAG repeat tract in the HTT gene, leading to motor, cognitive, and psychiatric symptoms. At the cellular level, NMDA-type glutamate receptors are upregulated at glutamatergic extrasynaptic sites in HD, triggering cell death signaling pathways and driving HD neurodegeneration. Extrasynaptic and synaptic glutamate receptor trafficking and surface distribution are regulated by the α and β N-terminal isoforms of SAP97, a postsynaptic density protein localized at glutamatergic synapses. Here we examined the surface distribution of NMDARs and AMPARs in a cellular model of HD, and whether the manipulation of individual SAP97 isoforms can regulate receptor distribution in diseased neurons. Using dSTORM super-resolution imaging, we reveal that mutant HTT drives the elevation of extrasynaptic NMDAR clusters located 100-500 nm from the postsynaptic density. This was accompanied by a decline in synaptic NMDAR-mediated currents while surface NMDAR-mediated currents remained unchanged. These effects were induced within 3 days of mutant HTT expression in rat hippocampal neurons in vitro, and were specific for NMDARs and not observed with AMPARs. Intriguingly, upregulation of either α- or βSAP97 expression increased synaptic and/or perisynaptic NMDAR localization and prevented the shift of NMDARs to extrasynaptic sites in mutant HTT neurons. This was accompanied by the rescue of normal synaptic NMDAR-mediated currents. Taken together, our high-resolution data reveals plasticity in surface NMDAR localization driven by mutant HTT and identifies the similar but independent roles of SAP97 N-terminal isoforms in maintaining normal synaptic function in pathological states.
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Affiliation(s)
- Wojciech Ambroziak
- Department of Physiology and Centre for Brain Research, The University of Auckland, Auckland, New Zealand
| | - Chantelle Fourie
- Department of Physiology and Centre for Brain Research, The University of Auckland, Auckland, New Zealand
| | - Johanna M Montgomery
- Department of Physiology and Centre for Brain Research, The University of Auckland, Auckland, New Zealand
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20
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Brouwer M, Farzana F, Koopmans F, Chen N, Brunner JW, Oldani S, Li KW, van Weering JR, Smit AB, Toonen RF, Verhage M. SALM1 controls synapse development by promoting F-actin/PIP2-dependent Neurexin clustering. EMBO J 2019; 38:e101289. [PMID: 31368584 PMCID: PMC6717895 DOI: 10.15252/embj.2018101289] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 06/20/2019] [Accepted: 06/25/2019] [Indexed: 11/17/2022] Open
Abstract
Synapse development requires spatiotemporally regulated recruitment of synaptic proteins. In this study, we describe a novel presynaptic mechanism of cis‐regulated oligomerization of adhesion molecules that controls synaptogenesis. We identified synaptic adhesion‐like molecule 1 (SALM1) as a constituent of the proposed presynaptic Munc18/CASK/Mint1/Lin7b organizer complex. SALM1 preferentially localized to presynaptic compartments of excitatory hippocampal neurons. SALM1 depletion in excitatory hippocampal primary neurons impaired Neurexin1β‐ and Neuroligin1‐mediated excitatory synaptogenesis and reduced synaptic vesicle clustering, synaptic transmission, and synaptic vesicle release. SALM1 promoted Neurexin1β clustering in an F‐actin‐ and PIP2‐dependent manner. Two basic residues in SALM1's juxtamembrane polybasic domain are essential for this clustering. Together, these data show that SALM1 is a presynaptic organizer of synapse development by promoting F‐actin/PIP2‐dependent clustering of Neurexin.
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Affiliation(s)
- Marinka Brouwer
- Department of Clinical Genetics, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University Amsterdam and VU Medical Center, Amsterdam, The Netherlands
| | - Fatima Farzana
- Department of Functional Genomics, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University Amsterdam and VU Medical Center, Amsterdam, The Netherlands
| | - Frank Koopmans
- Department of Functional Genomics, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University Amsterdam and VU Medical Center, Amsterdam, The Netherlands.,Department of Molecular and Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University Amsterdam and VU Medical Center, Amsterdam, The Netherlands
| | - Ning Chen
- Department of Functional Genomics, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University Amsterdam and VU Medical Center, Amsterdam, The Netherlands.,Department of Molecular and Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University Amsterdam and VU Medical Center, Amsterdam, The Netherlands
| | - Jessie W Brunner
- Department of Functional Genomics, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University Amsterdam and VU Medical Center, Amsterdam, The Netherlands
| | - Silvia Oldani
- Department of Functional Genomics, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University Amsterdam and VU Medical Center, Amsterdam, The Netherlands
| | - Ka Wan Li
- Department of Molecular and Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University Amsterdam and VU Medical Center, Amsterdam, The Netherlands
| | - Jan Rt van Weering
- Department of Clinical Genetics, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University Amsterdam and VU Medical Center, Amsterdam, The Netherlands
| | - August B Smit
- Department of Molecular and Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University Amsterdam and VU Medical Center, Amsterdam, The Netherlands
| | - Ruud F Toonen
- Department of Functional Genomics, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University Amsterdam and VU Medical Center, Amsterdam, The Netherlands
| | - Matthijs Verhage
- Department of Clinical Genetics, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University Amsterdam and VU Medical Center, Amsterdam, The Netherlands.,Department of Functional Genomics, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University Amsterdam and VU Medical Center, Amsterdam, The Netherlands
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21
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Mardones MD, Jorquera PV, Herrera-Soto A, Ampuero E, Bustos FJ, van Zundert B, Varela-Nallar L. PSD95 regulates morphological development of adult-born granule neurons in the mouse hippocampus. J Chem Neuroanat 2019; 98:117-123. [PMID: 31047946 DOI: 10.1016/j.jchemneu.2019.04.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 04/12/2019] [Accepted: 04/28/2019] [Indexed: 11/29/2022]
Abstract
In the adult hippocampus new neurons are generated in the dentate gyrus from neural progenitor cells. Adult-born neurons integrate into the hippocampal circuitry and contribute to hippocampal function. PSD95 is a major postsynaptic scaffold protein that is crucial for morphological maturation and synaptic development of hippocampal neurons. Here we study the function of PSD95 in adult hippocampal neurogenesis by downregulating PSD95 expression in newborn cells using retroviral-mediated RNA interference. Retroviruses coding for a control shRNA or an shRNA targeting PSD95 (shPSD95) were stereotaxically injected into the dorsal dentate gyrus of 2-month-old C57BL/6 mice. PSD95 knockdown did not affect neuronal differentiation of newborn cells into neurons, or migration of newborn neurons into the granule cell layer. Morphological analysis revealed that newborn neurons expressing shPSD95 showed increased dendritic length and increased number of high-order dendrites. Concomitantly, dendrites from shPSD95-expressing newborn granule neurons showed a reduction in the density of dendritic spines. These results suggest that PSD95 is required for proper dendritic and spine maturation of adult-born neurons, but not for early stages of neurogenesis in the hippocampus.
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Affiliation(s)
- Muriel D Mardones
- Institute of Biomedical Sciences, Faculty of Medicine and Faculty of Life Sciences, Universidad Andres Bello, Santiago, Chile
| | - Patricia V Jorquera
- Institute of Biomedical Sciences, Faculty of Medicine and Faculty of Life Sciences, Universidad Andres Bello, Santiago, Chile
| | - Andrea Herrera-Soto
- Institute of Biomedical Sciences, Faculty of Medicine and Faculty of Life Sciences, Universidad Andres Bello, Santiago, Chile
| | - Estibaliz Ampuero
- Instituto de Ciencias Biomédicas, Facultad de Ciencias de la Salud, Universidad Autónoma de Chile, Santiago, Chile
| | - Fernando J Bustos
- Institute of Biomedical Sciences, Faculty of Medicine and Faculty of Life Sciences, Universidad Andres Bello, Santiago, Chile; McGovern Institute for Brain Research, MIT, Cambridge, MA, United States
| | - Brigitte van Zundert
- Institute of Biomedical Sciences, Faculty of Medicine and Faculty of Life Sciences, Universidad Andres Bello, Santiago, Chile; Centro de Envejecimiento y Regeneración (CARE), P. Universidad Católica de Chile, Santiago, Chile
| | - Lorena Varela-Nallar
- Institute of Biomedical Sciences, Faculty of Medicine and Faculty of Life Sciences, Universidad Andres Bello, Santiago, Chile.
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22
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Dosemeci A, Loo HK, Toy D, Winters CA, Reese TS, Tao-Cheng JH. FAM81A protein, a novel component of the postsynaptic density in adult brain. Neurosci Lett 2019; 699:122-126. [PMID: 30735723 DOI: 10.1016/j.neulet.2019.02.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Revised: 02/01/2019] [Accepted: 02/04/2019] [Indexed: 11/18/2022]
Abstract
Analysis of affinity-purified PSD-95 complexes had previously identified a 'hypothetical protein', product of the gene FAM81A [1]. The present study examined the tissue and subcellular distribution of FAM81A protein and its expression levels during development. Comparison of different organs indicates selective expression of FAM81A protein in brain. FAM81A is expressed late in development, with a post-natal gradual increase in brain levels that parallels the expression of PSD-95. Comparison of subcellular fractions from adult brain shows that the distribution of FAM81A protein is similar to that of PSD-95, with a drastic enrichment in the postsynaptic density fraction. Immuno-electron microscopy of adult brain tissue reveals specific immunogold labeling for FAM81A protein at postsynaptic densities in the forebrain. The label for FAM81A protein is concentrated at the cytoplasmic edge of the electron-dense core of the postsynaptic density, with a mean distance of ∼33 nm from the postsynaptic membrane. These observations firmly establish FAM81A protein as a component of the postsynaptic density in the adult brain, suggesting a role in synaptic function.
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Affiliation(s)
- Ayse Dosemeci
- Laboratory of Neurobiology, NINDS, NIH, Bethesda, MD, United States.
| | - Hannah K Loo
- Laboratory of Neurobiology, NINDS, NIH, Bethesda, MD, United States
| | - Dana Toy
- Laboratory of Neurobiology, NINDS, NIH, Bethesda, MD, United States
| | | | - Thomas S Reese
- Laboratory of Neurobiology, NINDS, NIH, Bethesda, MD, United States
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Abnormal repetitive behaviors in zebrafish and their relevance to human brain disorders. Behav Brain Res 2019; 367:101-110. [PMID: 30926483 DOI: 10.1016/j.bbr.2019.03.044] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Revised: 03/22/2019] [Accepted: 03/25/2019] [Indexed: 02/01/2023]
Abstract
Abnormal repetitive behaviors (ARBs) are a prominent symptom of numerous human brain disorders and are commonly seen in rodent models as well. While rodent studies of ARBs continue to dominate the field, mounting evidence suggests that zebrafish (Danio rerio) also display ARB-like phenotypes and may therefore be a novel model organism for ARB research. In addition to clear practical research advantages as a model species, zebrafish share high genetic and physiological homology to humans and rodents, including multiple ARB-related genes and robust behaviors relevant to ARB. Here, we discuss a wide spectrum of stereotypic repetitive behaviors in zebrafish, data on their genetic and pharmacological modulation, and the overall translational relevance of fish ARBs to modeling human brain disorders. Overall, the zebrafish is rapidly emerging as a new promising model to study ARBs and their underlying mechanisms.
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Feng Z, Chen X, Zeng M, Zhang M. Phase separation as a mechanism for assembling dynamic postsynaptic density signalling complexes. Curr Opin Neurobiol 2018; 57:1-8. [PMID: 30599311 DOI: 10.1016/j.conb.2018.12.001] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Accepted: 12/04/2018] [Indexed: 10/27/2022]
Abstract
The postsynaptic density (PSD) is an electron dense, semi-membrane bound compartment that lies beneath postsynaptic membranes. This region is densely packed with thousands of proteins that are involved in extensive interactions. During synaptic plasticity, the PSD undergoes changes in size and composition along with changes in synaptic strength that lead to long term potentiation (LTP) or depression (LTD). It is therefore essential to understand the organization principles underlying PSD assembly and rearrangement. Here, we review exciting new findings from recent in vitro reconstitution studies and propose a hypothesis that liquid-liquid phase separation mediates PSD formation and regulation. We also discuss how the properties of PSD formed via phase separation might contribute to the biological functions observed from decades of researches. Finally, we highlight unanswered questions regarding PSD organization and how in vitro reconstitution systems may help to answer these questions in the coming years.
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Affiliation(s)
- Zhe Feng
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Xudong Chen
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Menglong Zeng
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Mingjie Zhang
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China; Center of Systems Biology and Human Health, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China.
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25
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Penny CJ, Gold MG. Mechanisms for localising calcineurin and CaMKII in dendritic spines. Cell Signal 2018; 49:46-58. [DOI: 10.1016/j.cellsig.2018.05.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Revised: 05/23/2018] [Accepted: 05/24/2018] [Indexed: 10/14/2022]
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26
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Reconstituted Postsynaptic Density as a Molecular Platform for Understanding Synapse Formation and Plasticity. Cell 2018; 174:1172-1187.e16. [PMID: 30078712 DOI: 10.1016/j.cell.2018.06.047] [Citation(s) in RCA: 234] [Impact Index Per Article: 39.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Revised: 05/17/2018] [Accepted: 06/26/2018] [Indexed: 11/21/2022]
Abstract
Synapses are semi-membraneless, protein-dense, sub-micron chemical reaction compartments responsible for signal processing in each and every neuron. Proper formation and dynamic responses to stimulations of synapses, both during development and in adult, are fundamental to functions of mammalian brains, although the molecular basis governing formation and modulation of compartmentalized synaptic assemblies is unclear. Here, we used a biochemical reconstitution approach to show that, both in solution and on supported membrane bilayers, multivalent interaction networks formed by major excitatory postsynaptic density (PSD) scaffold proteins led to formation of PSD-like assemblies via phase separation. The reconstituted PSD-like assemblies can cluster receptors, selectively concentrate enzymes, promote actin bundle formation, and expel inhibitory postsynaptic proteins. Additionally, the condensed phase PSD assemblies have features that are distinct from those in homogeneous solutions and fit for synaptic functions. Thus, we have built a molecular platform for understanding how neuronal synapses are formed and dynamically regulated.
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27
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Wigerius M, Quinn D, Diab A, Clattenburg L, Kolar A, Qi J, Krueger SR, Fawcett JP. The polarity protein Angiomotin p130 controls dendritic spine maturation. J Cell Biol 2018; 217:715-730. [PMID: 29317530 PMCID: PMC5800806 DOI: 10.1083/jcb.201705184] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Revised: 10/31/2017] [Accepted: 11/30/2017] [Indexed: 01/06/2023] Open
Abstract
Wigerius et al. identify the polarity protein AMOT-130 as vital for dendritic spine morphogenesis. They show that reduced Lats1 kinase activity in the neonatal brain is required for the recruitment of AMOT-130 to postsynaptic compartments to stabilize dendritic spines. The actin cytoskeleton is essential for the structural changes in dendritic spines that lead to the formation of new synapses. Although the molecular mechanisms underlying spine formation are well characterized, the events that drive spine maturation during development are largely unknown. In this study, we demonstrate that Angiomotin (AMOT-130) is necessary for spine stabilization. AMOT-130 is enriched in mature dendritic spines and functions to stabilize the actin cytoskeleton by coupling F-actin to postsynaptic protein scaffolds. These functions of AMOT are transiently restricted during postnatal development by phosphorylation imposed by the kinase Lats1. Our study proposes that AMOT-130 is essential for normal spine morphogenesis and identifies Lats1 as an upstream regulator in this process. Moreover, our findings may link AMOT-130 loss and the related spine defects to neurological disorders.
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Affiliation(s)
- Michael Wigerius
- Department of Pharmacology, Dalhousie University, Halifax, Canada
| | - Dylan Quinn
- Department of Physiology and Biophysics, Dalhousie University, Halifax, Canada
| | - Antonios Diab
- Department of Pharmacology, Dalhousie University, Halifax, Canada
| | | | - Annette Kolar
- Department of Physiology and Biophysics, Dalhousie University, Halifax, Canada
| | - Jiansong Qi
- Department of Pharmacology, Dalhousie University, Halifax, Canada
| | - Stefan R Krueger
- Department of Physiology and Biophysics, Dalhousie University, Halifax, Canada
| | - James P Fawcett
- Department of Pharmacology, Dalhousie University, Halifax, Canada .,Department of Surgery, Dalhousie University, Halifax, Canada
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28
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Suzuki T, Kametani K, Guo W, Li W. Protein components of post-synaptic density lattice, a backbone structure for type I excitatory synapses. J Neurochem 2017; 144:390-407. [PMID: 29134655 DOI: 10.1111/jnc.14254] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Revised: 10/17/2017] [Accepted: 11/01/2017] [Indexed: 12/31/2022]
Abstract
It is essential to study the molecular architecture of post-synaptic density (PSD) to understand the molecular mechanism underlying the dynamic nature of PSD, one of the bases of synaptic plasticity. A well-known model for the architecture of PSD of type I excitatory synapses basically comprises of several scaffolding proteins (scaffold protein model). On the contrary, 'PSD lattice' observed through electron microscopy has been considered a basic backbone of type I PSDs. However, major constituents of the PSD lattice and the relationship between the PSD lattice and the scaffold protein model, remain unknown. We purified a PSD lattice fraction from the synaptic plasma membrane of rat forebrain. Protein components of the PSD lattice were examined through immuno-gold negative staining electron microscopy. The results indicated that tubulin, actin, α-internexin, and Ca2+ /calmodulin-dependent kinase II are major constituents of the PSD lattice, whereas scaffold proteins such as PSD-95, SAP102, GKAP, Shank1, and Homer, were rather minor components. A similar structure was also purified from the synaptic plasma membrane of forebrains from 7-day-old rats. On the basis of this study, we propose a 'PSD lattice-based dynamic nanocolumn' model for PSD molecular architecture, in which the scaffold protein model and the PSD lattice model are combined and an idea of dynamic nanocolumn PSD subdomain is also included. In the model, cytoskeletal proteins, in particular, tubulin, actin, and α-internexin, may play major roles in the construction of the PSD backbone and provide linker sites for various PSD scaffold protein complexes/subdomains.
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Affiliation(s)
- Tatsuo Suzuki
- Department of Neuroplasticity, Institute of Pathogenesis and Disease Prevention, Graduate School of Medicine, Shinshu University Academic Assembly, Matsumoto, Japan.,Department of Biological Sciences for Intractable Neurological Diseases, Institute for Biomedical Sciences, Interdisciplinary Cluster for Cutting Edge Research Shinshu University, Matsumoto, Japan.,Department of Molecular and Cellular physiology, Shinshu University Academic Assembly, Institute of Medicine, Matsumoto, Japan
| | - Kiyokazu Kametani
- Department of Instrumental Analysis, Research Center for Human and Environmental Science, Shinshu University, Matsumoto, Nagano, Japan
| | - Weiheng Guo
- Department of Neuroplasticity, Institute of Pathogenesis and Disease Prevention, Graduate School of Medicine, Shinshu University Academic Assembly, Matsumoto, Japan
| | - Weidong Li
- Bio-X Institutes, Key Laboratory for the Genetics of Development and Neuropsychiatric Disorders (Ministry of Education), Shanghai Key Laboratory of Psychotic Disorders, and Brain Science and Technology Research Center, Shanghai Jiao Tong University, Shanghai, China.,Distinguished Visiting Professor, Institute for Biomedical Sciences, Interdisciplinary Cluster for Cutting Edge Research Shinshu University, Matsumoto, Japan
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29
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Coutinho E, Menassa DA, Jacobson L, West SJ, Domingos J, Moloney TC, Lang B, Harrison PJ, Bennett DLH, Bannerman D, Vincent A. Persistent microglial activation and synaptic loss with behavioral abnormalities in mouse offspring exposed to CASPR2-antibodies in utero. Acta Neuropathol 2017; 134:567-583. [PMID: 28755208 PMCID: PMC5587616 DOI: 10.1007/s00401-017-1751-5] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Revised: 07/12/2017] [Accepted: 07/13/2017] [Indexed: 12/30/2022]
Abstract
Gestational transfer of maternal antibodies against fetal neuronal proteins may be relevant to some neurodevelopmental disorders, but until recently there were no proteins identified. We recently reported a fivefold increase in CASPR2-antibodies in mid-gestation sera from mothers of children with intellectual and motor disabilities. Here, we exposed mice in utero to purified IgG from patients with CASPR2-antibodies (CASPR2-IgGs) or from healthy controls (HC-IgGs). CASPR2-IgG but not HC-IgG bound to fetal brain parenchyma, from which CASPR2-antibodies could be eluted. CASPR2-IgG exposed neonates achieved milestones similarly to HC-IgG exposed controls but, when adult, the CASPR2-IgG exposed progeny showed marked social interaction deficits, abnormally located glutamatergic neurons in layers V-VI of the somatosensory cortex, a 16% increase in activated microglia, and a 15-52% decrease in glutamatergic synapses in layers of the prefrontal and somatosensory cortices. Thus, in utero exposure to CASPR2-antibodies led to permanent behavioral, cellular, and synaptic abnormalities. These findings support a pathogenic role for maternal antibodies in human neurodevelopmental conditions, and CASPR2 as a potential target.
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Affiliation(s)
- Ester Coutinho
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - David A Menassa
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - Leslie Jacobson
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - Steven J West
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - Joana Domingos
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - Teresa C Moloney
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - Bethan Lang
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - Paul J Harrison
- Department of Psychiatry, University of Oxford, Oxford, UK
- Oxford Health NHS Foundation Trust, Oxford, UK
| | - David L H Bennett
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - David Bannerman
- Department of Experimental Psychology, University of Oxford, Oxford, UK
| | - Angela Vincent
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK.
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, Oxford, OX3 9DU, UK.
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30
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The Arp2/3 Complex Is Essential for Distinct Stages of Spine Synapse Maturation, Including Synapse Unsilencing. J Neurosci 2017; 36:9696-709. [PMID: 27629719 DOI: 10.1523/jneurosci.0876-16.2016] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Accepted: 08/02/2016] [Indexed: 12/28/2022] Open
Abstract
UNLABELLED Dendritic filopodia are actin-rich structures that are thought to contribute to early spine synapse formation; however, the actin regulatory proteins important for early synaptogenesis are poorly defined. Using organotypic hippocampal slice cultures and primary neuron hippocampal cultures from Arp2/3 conditional knock-out mice, we analyze the roles of the Arp2/3 complex, an actin regulator that creates branched actin networks, and demonstrate it is essential for distinct stages of both structural and functional maturation of excitatory spine synapses. Our data show that initially the Arp2/3 complex inhibits the formation of dendritic filopodia but that later during development, the Arp2/3 complex drives the morphological maturation from filopodia to typical spine morphology. Furthermore, we demonstrate that although the Arp2/3 complex is not required for key spine maturation steps, such as presynaptic contact and recruitment of MAGUK (membrane-associated guanylate kinase) scaffolding proteins or NMDA receptors, it is necessary for the recruitment of AMPA receptors. This latter process, also known as synapse unsilencing, is a final and essential step in the neurodevelopment of excitatory postsynaptic synaptogenesis, setting the stage for neuronal interconnectivity. These findings provide the first evidence that the Arp2/3 complex is directly involved in functional maturation of dendritic spines during the developmental period of spinogenesis. SIGNIFICANCE STATEMENT Excitatory spine synapse formation (spinogenesis) is a poorly understood yet pivotal period of neurodevelopment that occurs within 2-3 weeks after birth. Neurodevelopmental disorders such as intellectual disability and autism are characterized by abnormal spine structure, which may arise from abnormal excitatory synaptogenesis. The initial stage of spinogenesis is thought to begin with the emergence of actin-rich dendritic filopodia that initiate contact with presynaptic axonal boutons. However, it remains enigmatic how actin cytoskeletal regulation directs dendritic filopodial emergence or their subsequent maturation into dendritic spines during development and on into adulthood. In this study, we provide the first evidence that the Arp2/3 complex, a key actin nucleator, is involved in distinct stages of spine formation and is required for synapse unsilencing.
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31
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van Deijk ALF, Broersen LM, Verkuyl JM, Smit AB, Verheijen MHG. High Content Analysis of Hippocampal Neuron-Astrocyte Co-cultures Shows a Positive Effect of Fortasyn Connect on Neuronal Survival and Postsynaptic Maturation. Front Neurosci 2017; 11:440. [PMID: 28824363 PMCID: PMC5543085 DOI: 10.3389/fnins.2017.00440] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Accepted: 07/19/2017] [Indexed: 01/01/2023] Open
Abstract
Neuronal and synaptic membranes are composed of a phospholipid bilayer. Supplementation with dietary precursors for phospholipid synthesis –docosahexaenoic acid (DHA), uridine and choline– has been shown to increase neurite outgrowth and synaptogenesis both in vivo and in vitro. A role for multi-nutrient intervention with specific precursors and cofactors has recently emerged in early Alzheimer's disease, which is characterized by decreased synapse numbers in the hippocampus. Moreover, the medical food Souvenaid, containing the specific nutrient combination Fortasyn Connect (FC), improves memory performance in early Alzheimer's disease patients, possibly via maintaining brain connectivity. This suggests an effect of FC on synapses, but the underlying cellular mechanism is not fully understood. Therefore, we investigated the effect of FC (consisting of DHA, eicosapentaenoic acid (EPA), uridine, choline, phospholipids, folic acid, vitamins B12, B6, C and E, and selenium), on synaptogenesis by supplementing it to primary neuron-astrocyte co-cultures, a cellular model that mimics metabolic dependencies in the brain. We measured neuronal developmental processes using high content screening in an automated manner, including neuronal survival, neurite morphology, as well as the formation and maturation of synapses. Here, we show that FC supplementation resulted in increased numbers of neurons without affecting astrocyte number. Furthermore, FC increased postsynaptic PSD95 levels in both immature and mature synapses. These findings suggest that supplementation with FC to neuron-astrocyte co-cultures increased both neuronal survival and the maturation of postsynaptic terminals, which might aid the functional interpretation of FC-based intervention strategies in neurological diseases characterized by neuronal loss and impaired synaptic functioning.
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Affiliation(s)
- Anne-Lieke F van Deijk
- Department of Molecular and Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, VU University AmsterdamAmsterdam, Netherlands
| | - Laus M Broersen
- Advanced Medical Nutrition, Nutricia ResearchUtrecht, Netherlands
| | - J Martin Verkuyl
- Advanced Medical Nutrition, Nutricia ResearchUtrecht, Netherlands
| | - August B Smit
- Department of Molecular and Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, VU University AmsterdamAmsterdam, Netherlands
| | - Mark H G Verheijen
- Department of Molecular and Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, VU University AmsterdamAmsterdam, Netherlands
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Goulding SP, Szumlinski KK, Contet C, MacCoss MJ, Wu CC. A mass spectrometry-based proteomic analysis of Homer2-interacting proteins in the mouse brain. J Proteomics 2017; 166:127-137. [PMID: 28728878 DOI: 10.1016/j.jprot.2017.07.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Revised: 07/08/2017] [Accepted: 07/12/2017] [Indexed: 11/26/2022]
Abstract
In the brain, the Homer protein family modulates excitatory signal transduction and receptor plasticity through interactions with other proteins in dendritic spines. Homer proteins are implicated in a variety of psychiatric disorders such as schizophrenia and addiction. Since long Homers serve as scaffolding proteins, identifying their interacting partners is an important first step in understanding their biological function and could help to guide the design of new therapeutic strategies. The present study set out to document Homer2-interacting proteins in the mouse brain using a co-immunoprecipitation-based mass spectrometry approach where Homer2 knockout samples were used to filter out non-specific interactors. We found that in the mouse brain, Homer2 interacts with a limited subset of its previously reported interacting partners (3 out of 31). Importantly, we detected an additional 15 novel Homer2-interacting proteins, most of which are part of the N-methyl-D-aspartate receptor signaling pathway. These results corroborate the central role Homer2 plays in glutamatergic transmission and expand the network of proteins potentially contributing to the behavioral abnormalities associated with altered Homer2 expression. SIGNIFICANCE Long Homer proteins are scaffolding proteins that regulate signal transduction in neurons. Identifying their interacting partners is key to understanding their function. We used co-immunoprecipitation in combination with mass spectrometry to establish the first comprehensive list of Homer2-interacting partners in the mouse brain. The specificity of interactions was evaluated using Homer2 knockout brain tissue as a negative control. The set of proteins that we identified minimally overlaps with previously reported interacting partners of Homer2; however, we identified novel interactors that are part of a signaling cascade activated by glutamatergic transmission, which improves our mechanistic understanding of the role of Homer2 in behavior.
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Affiliation(s)
- Scott P Goulding
- Department of Neuroscience, The Scripps Research Institute, La Jolla, CA, United States; Neuroscience Program, University of Colorado Anschutz Medical Campus, Aurora, CO, United States; Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States; Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA, United States.
| | - Karen K Szumlinski
- Department of Psychological and Brain Sciences, Molecular, Cellular and Developmental Biology, The Neuroscience Research Institute, University of California, Santa Barbara, Santa Barbara, CA, United States
| | - Candice Contet
- Department of Neuroscience, The Scripps Research Institute, La Jolla, CA, United States
| | - Michael J MacCoss
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA, United States
| | - Christine C Wu
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
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Scott H, Rogers MF, Scott HL, Campbell C, Warburton EC, Uney JB. Recognition memory-induced gene expression in the perirhinal cortex: A transcriptomic analysis. Behav Brain Res 2017; 328:1-12. [PMID: 28389337 PMCID: PMC5469443 DOI: 10.1016/j.bbr.2017.04.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Revised: 03/15/2017] [Accepted: 04/03/2017] [Indexed: 12/20/2022]
Abstract
We have used transcriptome analysis to identify genes and pathways that are activated during recognition memory formation in the perirhinal cortex. Rats were exposed to objects either repeatedly, so that the objects become familiar, or to novel objects in a bow-tie maze over six consecutive days. On the final day, one hour after the last exposure to the series of objects, RNA from the perirhinal cortex was sequenced to compare the transcriptome of naïve control rats and rats exposed to either novel or familiar stimuli. Differentially expressed genes were identified between group Novel and group Familiar rats. These included genes coding for transcription factors, GDNF receptors and extracellular matrix-related proteins. Moreover, differences in alternative splicing were also detected between the two groups, which suggests that this post-transcriptional mechanism may play a role in the consolidation of object recognition memory. To conclude, this study shows that RNA sequencing can be used as a tool to identify differences in gene expression in behaving animals undergoing the same task but encountering different exposures.
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Affiliation(s)
- Hannah Scott
- School of Physiology and Pharmacology, University of Bristol BS8 1TD, UK; School of Clinical Sciences, University of Bristol BS8 1TD, UK.
| | - Mark F Rogers
- Intelligent Systems Laboratory, Department of Engineering Mathematics, University of Bristol BS8 1TD, UK
| | - Helen L Scott
- School of Clinical Sciences, University of Bristol BS8 1TD, UK
| | - Colin Campbell
- Intelligent Systems Laboratory, Department of Engineering Mathematics, University of Bristol BS8 1TD, UK
| | | | - James B Uney
- School of Clinical Sciences, University of Bristol BS8 1TD, UK
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Lauterborn JC, Kramár EA, Rice JD, Babayan AH, Cox CD, Karsten CA, Gall CM, Lynch G. Cofilin Activation Is Temporally Associated with the Cessation of Growth in the Developing Hippocampus. Cereb Cortex 2017; 27:2640-2651. [PMID: 27073215 PMCID: PMC5964364 DOI: 10.1093/cercor/bhw088] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Dendritic extension and synaptogenesis proceed at high rates in rat hippocampus during early postnatal life but markedly slow during the third week of development. The reasons for the latter, fundamental event are poorly understood. Here, we report that levels of phosphorylated (inactive) cofilin, an actin depolymerizing factor, decrease by 90% from postnatal days (pnds) 10 to 21. During the same period, levels of total and phosphorylated Arp2, which nucleates actin branches, increase. A search for elements that could explain the switch from inactive to active cofilin identified reductions in β1 integrin, TrkB, and LIM domain kinase 2b, upstream proteins that promote cofilin phosphorylation. Moreover, levels of slingshot 3, which dephosphorylates cofilin, increase during the period in which growth slows. Consistent with the cofilin results, in situ phalloidin labeling of F-actin demonstrated that spines and dendrites contained high levels of dynamic actin filaments during Week 2, but these fell dramatically by pnd 21. The results suggest that the change from inactive to constitutively active cofilin leads to a loss of dynamic actin filaments needed for process extension and thus the termination of spine formation and synaptogenesis. The relevance of these events to the emergence of memory-related synaptic plasticity is described.
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Affiliation(s)
| | | | | | | | | | | | - Christine M. Gall
- Department of Anatomy and Neurobiology
- Department of Neurobiology and Behavior
| | - Gary Lynch
- Department of Anatomy and Neurobiology
- Department of Psychiatry and Human Behavior, University of California at Irvine, Irvine, CA 92697, USA
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35
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A novel synaptic junction preparation for the identification and characterization of cleft proteins. PLoS One 2017; 12:e0174895. [PMID: 28362857 PMCID: PMC5376301 DOI: 10.1371/journal.pone.0174895] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2016] [Accepted: 03/16/2017] [Indexed: 12/23/2022] Open
Abstract
Identification of synaptic cleft components has been hampered by the lack of a suitable preparation enriched in synaptic junctions devoid of adjoining peripheral membranes. Prior strategies for the isolation of synaptic junctions, relying on detergents for the removal of peripheral membranes, resulted in substantial loss of membranes lining the cleft. Here, a novel, detergent-free method is described for the preparation of a synaptic junction (SJ) fraction, using phospholipase A2. Limited digestion of synaptic plasma membrane (SPM) fraction with phospholipase A2 followed by centrifugation over a sucrose cushion results in selective removal of membranes peripheral to the cleft while junctional membranes remain relatively intact as observed by electron microscopy. Enrichment in synaptic junctional structures and loss of membranes peripheral to the junctional area are further verified by demonstrating enrichment in PSD-95 and loss in mGluR5, respectively. The SJ fraction is enriched in neuroligins and neurexins, in agreement with immuno-electron microscopy data showing their selective localization to the junctional area. Among additional cell adhesion molecules tested, N-cadherin and specific isoforms of the SynCAM and SALM families also show marked enrichment in the SJ fraction, suggesting preferential localization at the synaptic cleft while others show little enrichment or decrease, suggesting that they are not restricted to or concentrated at the synaptic cleft. Treatment of the SJ fraction with glycosidases results in electrophoretic mobility shifts of all cell adhesion molecules tested, indicating glycosylation at the synaptic cleft. Biochemical and ultrastructural data presented indicate that the novel synaptic junction preparation can be used as a predictive tool for the identification and characterization of the components of the synaptic cleft.
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Won S, Levy JM, Nicoll RA, Roche KW. MAGUKs: multifaceted synaptic organizers. Curr Opin Neurobiol 2017; 43:94-101. [PMID: 28236779 DOI: 10.1016/j.conb.2017.01.006] [Citation(s) in RCA: 97] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Revised: 01/25/2017] [Accepted: 01/30/2017] [Indexed: 11/19/2022]
Abstract
The PSD-95 family of proteins, known as MAGUKs, have long been recognized to be central building blocks of the PSD. They are categorized as scaffolding proteins, which link surface-expressed receptors to the intracellular signaling molecules. Although the four members of the PSD-95 family (PSD-95, PSD-93, SAP102, and SAP97) have many shared roles in regulating synaptic function, recent studies have begun to delineate specific binding partners and roles in plasticity. In the current review, we will highlight the conserved and unique roles of these proteins.
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Affiliation(s)
- Sehoon Won
- Receptor Biology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, United States
| | - Jon M Levy
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, United States
| | - Roger A Nicoll
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, CA 94158, United States; Department of Physiology, University of California, San Francisco, CA 94158, United States
| | - Katherine W Roche
- Receptor Biology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, United States.
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Aoki C, Sherpa AD. Making of a Synapse: Recurrent Roles of Drebrin A at Excitatory Synapses Throughout Life. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 1006:119-139. [DOI: 10.1007/978-4-431-56550-5_8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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Dincheva I, Lynch NB, Lee FS. The Role of BDNF in the Development of Fear Learning. Depress Anxiety 2016; 33:907-916. [PMID: 27699937 PMCID: PMC5089164 DOI: 10.1002/da.22497] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2016] [Accepted: 02/22/2016] [Indexed: 01/15/2023] Open
Abstract
Brain-derived neurotrophic factor (BDNF) is a growth factor that is dynamically expressed in the brain across postnatal development, regulating neuronal differentiation and synaptic plasticity. The neurotrophic hypothesis of psychiatric mood disorders postulates that in the adult brain, decreased BDNF levels leads to altered neural plasticity, contributing to disease. Although BDNF has been established as a key factor regulating the critical period plasticity in the developing visual system, it has recently been shown to also play a role in fear circuitry maturation, which has implications for the emergence of fear-related mood disorders. This review provides a detailed overview of developmental changes in expression of BDNF isoforms, as well as their receptors across postnatal life. In addition, recent developmental studies utilizing a genetic BDNF single nucleotide polymorphism (Val66Met) knock-in mouse highlight the impact of BDNF on fear learning during a sensitive period spanning the transition into adolescent time frame. We hypothesize that BDNF in the developing brain regulates fear circuit plasticity during a sensitive period in early adolescence, and alterations in BDNF expression (genetic or environmental) have a persistent impact on fear behavior and fear-related disorders.
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Affiliation(s)
- Iva Dincheva
- Department of Psychiatry, Weill Cornell Medical College of Cornell University, New York, New York.
| | - Niccola B. Lynch
- Department of Psychiatry, Weill Cornell Medical College of Cornell University, New York, New York
| | - Francis S. Lee
- Department of Psychiatry, Weill Cornell Medical College of Cornell University, New York, New York,Department of Pharmacology, Weill Cornell Medical College of Cornell University, New York, New York,Sackler Institute for Developmental Psychobiology, Weill Cornell Medical College of Cornell University, New York, New York
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Dosemeci A, Weinberg RJ, Reese TS, Tao-Cheng JH. The Postsynaptic Density: There Is More than Meets the Eye. Front Synaptic Neurosci 2016; 8:23. [PMID: 27594834 PMCID: PMC4990544 DOI: 10.3389/fnsyn.2016.00023] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Accepted: 07/25/2016] [Indexed: 11/28/2022] Open
Abstract
The postsynaptic density (PSD), apparent in electron micrographs as a dense lamina just beneath the postsynaptic membrane, includes a deeper layer, the “pallium”, containing a scaffold of Shank and Homer proteins. Though poorly defined in traditionally prepared thin-section electron micrographs, the pallium becomes denser and more conspicuous during intense synaptic activity, due to the reversible addition of CaMKII and other proteins. In this Perspective article, we review the significance of CaMKII-mediated recruitment of proteins to the pallium with respect to both the trafficking of receptors and the remodeling of spine shape that follow synaptic stimulation. We suggest that the level and duration of CaMKII translocation and activation in the pallium will shape activity-induced changes in the spine.
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Affiliation(s)
- Ayse Dosemeci
- Laboratory of Neurobiology, National Institute of Neurological Disorders and Stroke (NINDS), National Institutes of Health (NIH) Bethesda, MD, USA
| | - Richard J Weinberg
- Department of Cell Biology and Physiology, University of North Carolina, Chapel Hill Chapel Hill, NC, USA
| | - Thomas S Reese
- Laboratory of Neurobiology, National Institute of Neurological Disorders and Stroke (NINDS), National Institutes of Health (NIH) Bethesda, MD, USA
| | - Jung-Hwa Tao-Cheng
- Electron Microscopy Facility, National Institute of Neurological Disorders and Stroke (NINDS), National Institutes of Health (NIH) Bethesda, MD, USA
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Tulodziecka K, Diaz-Rohrer BB, Farley MM, Chan RB, Di Paolo G, Levental KR, Waxham MN, Levental I. Remodeling of the postsynaptic plasma membrane during neural development. Mol Biol Cell 2016; 27:3480-3489. [PMID: 27535429 PMCID: PMC5221582 DOI: 10.1091/mbc.e16-06-0420] [Citation(s) in RCA: 78] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Accepted: 08/04/2016] [Indexed: 11/29/2022] Open
Abstract
Neuronal synapses require precise regulation, particularly of membrane components. The composition and organization of synaptic membranes are dramatically remodeled during development, including accumulation of lipids associated with raft domains, and concomitant palmitoylation of PSD-95, suggesting recruitment of domains via scaffold lipidation. Neuronal synapses are the fundamental units of neural signal transduction and must maintain exquisite signal fidelity while also accommodating the plasticity that underlies learning and development. To achieve these goals, the molecular composition and spatial organization of synaptic terminals must be tightly regulated; however, little is known about the regulation of lipid composition and organization in synaptic membranes. Here we quantify the comprehensive lipidome of rat synaptic membranes during postnatal development and observe dramatic developmental lipidomic remodeling during the first 60 postnatal days, including progressive accumulation of cholesterol, plasmalogens, and sphingolipids. Further analysis of membranes associated with isolated postsynaptic densities (PSDs) suggests the PSD-associated postsynaptic plasma membrane (PSD-PM) as one specific location of synaptic remodeling. We analyze the biophysical consequences of developmental remodeling in reconstituted synaptic membranes and observe remarkably stable microdomains, with the stability of domains increasing with developmental age. We rationalize the developmental accumulation of microdomain-forming lipids in synapses by proposing a mechanism by which palmitoylation of the immobilized scaffold protein PSD-95 nucleates domains at the postsynaptic plasma membrane. These results reveal developmental changes in lipid composition and palmitoylation that facilitate the formation of postsynaptic membrane microdomains, which may serve key roles in the function of the neuronal synapse.
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Affiliation(s)
- Karolina Tulodziecka
- Department of Integrative Biology and Pharmacology, McGovern Medical School at the University of Texas Health Science Center at Houston, Houston, TX 77030
| | - Barbara B Diaz-Rohrer
- Department of Integrative Biology and Pharmacology, McGovern Medical School at the University of Texas Health Science Center at Houston, Houston, TX 77030
| | - Madeline M Farley
- Department of Neurobiology and Anatomy, McGovern Medical School at the University of Texas Health Science Center at Houston, Houston, TX 77030
| | - Robin B Chan
- Department of Pathology and Cell Biology, Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Medical Center, New York, NY 10032
| | - Gilbert Di Paolo
- Department of Pathology and Cell Biology, Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Medical Center, New York, NY 10032
| | - Kandice R Levental
- Department of Integrative Biology and Pharmacology, McGovern Medical School at the University of Texas Health Science Center at Houston, Houston, TX 77030
| | - M Neal Waxham
- Department of Neurobiology and Anatomy, McGovern Medical School at the University of Texas Health Science Center at Houston, Houston, TX 77030
| | - Ilya Levental
- Department of Integrative Biology and Pharmacology, McGovern Medical School at the University of Texas Health Science Center at Houston, Houston, TX 77030
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Impairment of synaptic development in the hippocampus of diabetic Goto-Kakizaki rats. Int J Dev Neurosci 2016; 53:58-67. [PMID: 27444810 DOI: 10.1016/j.ijdevneu.2016.07.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2016] [Revised: 06/30/2016] [Accepted: 07/17/2016] [Indexed: 12/28/2022] Open
Abstract
Insulin receptor signaling has been shown to regulate essential aspects of CNS function such as synaptic plasticity and neuronal survival. To elucidate its roles during CNS development in vivo, we examined the synaptic and cognitive development of the spontaneously diabetic Goto-Kakizaki (GK) rats in the present study. GK rats are non-obese models of type 2 diabetes established by selective inbreeding of Wistar rats based on impaired glucose tolerance. Though they start exhibiting only moderate hyperglycemia without changes in plasma insulin levels from 3 weeks postnatally, behavioral alterations in the open-field as well as significant impairments in memory retention compared with Wistar rats were observed at 10 weeks and were worsened at 20 weeks. Alterations in insulin receptor signaling and signs of insulin resistance were detected in the GK rat hippocampus at 3 weeks, as early as in other insulin-responsive peripheral tissues. Significant reduction of an excitatory postsynaptic scaffold protein, PSD95, was found at 5w and later in the hippocampus of GK rats due to the absence of a two-fold developmental increase of this protein observed in Wistar control rats between 3 and 20w. In the GK rat hippocampus, NR2A which is a NMDA receptor subunit selectively anchored to PSD95 was also reduced. In contrast, both NR2B and its anchoring protein, SAP102, showed similar developmental profiles in Wistar and GK rats with expression peaks at 2 and 3w. The results suggest that early alterations in insulin receptor signaling in the GK rat hippocampus may affect cognitive performance by suppressing synaptic maturation.
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Immunostaining for Homer reveals the majority of excitatory synapses in laminae I-III of the mouse spinal dorsal horn. Neuroscience 2016; 329:171-81. [PMID: 27185486 PMCID: PMC4915440 DOI: 10.1016/j.neuroscience.2016.05.009] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Revised: 05/01/2016] [Accepted: 05/06/2016] [Indexed: 12/25/2022]
Abstract
Identifying glutamatergic synapses is important for tracing synaptic circuits. Most proteins at glutamatergic synapses are masked by tissue fixation. Homer can reveal glutamatergic synapses without the need for antigen retrieval.
The spinal dorsal horn processes somatosensory information before conveying it to the brain. The neuronal organization of the dorsal horn is still poorly understood, although recent studies have defined several distinct populations among the interneurons, which account for most of its constituent neurons. All primary afferents, and the great majority of neurons in laminae I–III are glutamatergic, and a major factor limiting our understanding of the synaptic circuitry has been the difficulty in identifying glutamatergic synapses with light microscopy. Although there are numerous potential targets for antibodies, these are difficult to visualize with immunocytochemistry, because of protein cross-linking following tissue fixation. Although this can be overcome by antigen retrieval methods, these lead to difficulty in detecting other antigens. The aim of this study was to test whether the postsynaptic protein Homer can be used to reveal glutamatergic synapses in the dorsal horn. Immunostaining for Homer gave punctate labeling when viewed by confocal microscopy, and this was restricted to synapses at the ultrastructural level. We found that Homer puncta were colocalized with the AMPA receptor GluR2 subunit, but not with the inhibitory synapse-associated protein gephyrin. We also examined several populations of glutamatergic axons and found that most boutons were in contact with at least one Homer punctum. These results suggest that Homer antibodies can be used to reveal the great majority of glutamatergic synapses without antigen retrieval. This will be of considerable value in tracing synaptic circuits, and also in investigating plasticity of glutamatergic synapses in pain states.
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Lo FS, Blue ME, Erzurumlu RS. Enhancement of postsynaptic GABAA and extrasynaptic NMDA receptor-mediated responses in the barrel cortex of Mecp2-null mice. J Neurophysiol 2015; 115:1298-306. [PMID: 26683074 DOI: 10.1152/jn.00944.2015] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Accepted: 12/15/2015] [Indexed: 12/12/2022] Open
Abstract
Rett syndrome (RTT) is a neurodevelopmental disorder that results from mutations in the X-linked gene for methyl-CpG-binding protein 2 (MECP2). The underlying cellular mechanism for the sensory deficits in patients with RTT is largely unknown. This study used the Bird mouse model of RTT to investigate sensory thalamocortical synaptic transmission in the barrel cortex of Mecp2-null mice. Electrophysiological results showed an excitation/inhibition imbalance, biased toward inhibition, due to an increase in efficacy of postsynaptic GABAA receptors rather than alterations in inhibitory network and presynaptic release properties. Enhanced inhibition impaired the transmission of tonic sensory signals from the thalamus to the somatosensory cortex. Previous morphological studies showed an upregulation of NMDA receptors in the neocortex of both RTT patients and Mecp2-null mice at early ages [Blue ME, Naidu S, Johnston MV. Ann Neurol 45: 541-545, 1999; Blue ME, Kaufmann WE, Bressler J, Eyring C, O'Driscoll C, Naidu S, Johnston MV. Anat Rec (Hoboken) 294: 1624-1634, 2011]. Although AMPA and NMDA receptor-mediated excitatory synaptic transmission was not altered in the barrel cortex of Mecp2-null mice, extrasynaptic NMDA receptor-mediated responses increased markedly. These responses were blocked by memantine, suggesting that extrasynaptic NMDA receptors play an important role in the pathogenesis of RTT. The results suggest that enhancement of postsynaptic GABAA and extrasynaptic NMDA receptor-mediated responses may underlie impaired somatosensation and that pharmacological blockade of extrasynaptic NMDA receptors may have therapeutic value for RTT.
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Affiliation(s)
- Fu-Sun Lo
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland; and
| | - Mary E Blue
- Hugo W. Moser Research Institute at Kennedy Krieger, Inc. and Departments of Neurology and Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Reha S Erzurumlu
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland; and
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Depolarization of Hippocampal Neurons Induces Formation of Nonsynaptic NMDA Receptor Islands Resembling Nascent Postsynaptic Densities. eNeuro 2015; 2:eN-NWR-0066-15. [PMID: 26665164 PMCID: PMC4672205 DOI: 10.1523/eneuro.0066-15.2015] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Revised: 10/15/2015] [Accepted: 11/03/2015] [Indexed: 01/11/2023] Open
Abstract
Depolarization of neurons in 3-week-old rat hippocampal cultures promotes a rapid increase in the density of surface NMDA receptors (NRs), accompanied by transient formation of nonsynaptic NMDA receptor clusters or NR islands. Islands exhibit cytoplasmic dense material resembling that at postsynaptic densities (PSDs), and contain typical PSD components, including MAGUKS (membrane-associated guanylate kinases), GKAP, Shank, Homer, and CaMKII detected by pre-embedding immunogold electron microscopy. In contrast to mature PSDs, islands contain more NMDA than AMPA receptors, and more SAP102 than PSD-95, features that are shared with nascent PSDs in developing synapses. Islands do not appear to be exocytosed or endocytosed directly as preformed packages because neurons lacked intracellular vacuoles containing island-like structures. Islands form and disassemble upon depolarization of neurons on a time scale of 2-3 min, perhaps representing an initial stage in synaptogenesis.
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45
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Electron tomographic structure and protein composition of isolated rat cerebellar, hippocampal and cortical postsynaptic densities. Neuroscience 2015. [PMID: 26215919 DOI: 10.1016/j.neuroscience.2015.07.062] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Electron tomography and immunogold labeling were used to analyze similarities and differences in the morphology and protein composition of postsynaptic densities (PSDs) isolated from adult rat cerebella, hippocampi, and cortices. There were similarities in physical dimensions and gross morphology between cortical, hippocampal and most cerebellar PSDs, although the morphology among cerebellar PSDs could be categorized into three distinct groups. The majority of cerebellar PSDs were composed of dense regions of protein, similar to cortical and hippocampal PSDs, while others were either composed of granular or lattice-like protein regions. Significant differences were found in protein composition and organization across PSDs from the different brain regions. The signaling protein, βCaMKII, was found to be a major component of each PSD type and was more abundant than αCaMKII in both hippocampal and cerebellar PSDs. The scaffold molecule PSD-95, a major component of cortical PSDs, was found absent in a fraction of cerebellar PSDs and when present was clustered in its distribution. In contrast, immunogold labeling for the proteasome was significantly more abundant in cerebellar and hippocampal PSDs than cortical PSDs. Together, these results indicate that PSDs exhibit remarkable diversity in their composition and morphology, presumably as a reflection of the unique functional demands placed on different synapses.
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46
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Burette AC, Phend KD, Burette S, Lin Q, Liang M, Foltz G, Taylor N, Wang Q, Brandon NJ, Bates B, Ehlers MD, Weinberg RJ. Organization of TNIK in dendritic spines. J Comp Neurol 2015; 523:1913-24. [PMID: 25753355 DOI: 10.1002/cne.23770] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Revised: 02/25/2015] [Accepted: 02/26/2015] [Indexed: 01/16/2023]
Abstract
Tumor necrosis factor receptor-associated factor 2 (TRAF2)- and noncatalytic region of tyrosine kinase (NCK)-interacting kinase (TNIK) has been identified as an interactor in the psychiatric risk factor, Disrupted in Schizophrenia 1 (DISC1). As a step toward deciphering its function in the brain, we performed high-resolution light and electron microscopic immunocytochemistry. We demonstrate here that TNIK is expressed in neurons throughout the adult mouse brain. In striatum and cerebral cortex, TNIK concentrates in dendritic spines, especially in the vicinity of the lateral edge of the synapse. Thus, TNIK is highly enriched at a microdomain critical for glutamatergic signaling.
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Affiliation(s)
- Alain C Burette
- Department of Cell Biology & Physiology, University of North Carolina, Chapel Hill, North Carolina, 27599
| | - Kristen D Phend
- Department of Cell Biology & Physiology, University of North Carolina, Chapel Hill, North Carolina, 27599
| | - Susan Burette
- Department of Cell Biology & Physiology, University of North Carolina, Chapel Hill, North Carolina, 27599
| | - Qingcong Lin
- Shenogen Pharma Group, Beijing, People's Republic of China 102206
| | - Musen Liang
- Department of Pharmacokinetics, Dynamics, and Metabolism, Pfizer, Andover, Massachusetts 01810
| | - Gretchen Foltz
- Clinical Research Unit, Pfizer, New Haven, Connecticut 06511
| | - Noël Taylor
- Biomarker and Personalized Medicine Group, Eisai Product Creation Systems, Eisai, Andover, Massachusetts 01810
| | - Qi Wang
- Neuroscience Research Unit, Pfizer, Cambridge, Massachusetts 02139
| | | | - Brian Bates
- Centers for Therapeutic Innovation, Pfizer, Boston, Massachusetts 02115
| | - Michael D Ehlers
- Neuroscience Research Unit, Pfizer, Cambridge, Massachusetts 02139
| | - Richard J Weinberg
- Department of Cell Biology & Physiology, University of North Carolina, Chapel Hill, North Carolina, 27599.,Neuroscience Center, University of North Carolina, Chapel Hill, North Carolina, 27599
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Lee J, Chung C, Ha S, Lee D, Kim DY, Kim H, Kim E. Shank3-mutant mice lacking exon 9 show altered excitation/inhibition balance, enhanced rearing, and spatial memory deficit. Front Cell Neurosci 2015; 9:94. [PMID: 25852484 PMCID: PMC4365696 DOI: 10.3389/fncel.2015.00094] [Citation(s) in RCA: 111] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Accepted: 03/02/2015] [Indexed: 12/24/2022] Open
Abstract
Shank3 is a postsynaptic scaffolding protein implicated in synapse development and autism spectrum disorders. The Shank3 gene is known to produce diverse splice variants whose functions have not been fully explored. In the present study, we generated mice lacking Shank3 exon 9 (Shank3 (Δ9) mice), and thus missing five out of 10 known Shank3 splice variants containing the N-terminal ankyrin repeat region, including the longest splice variant, Shank3a. Our X-gal staining results revealed that Shank3 proteins encoded by exon 9-containing splice variants are abundant in upper cortical layers, striatum, hippocampus, and thalamus, but not in the olfactory bulb or cerebellum, despite the significant Shank3 mRNA levels in these regions. The hippocampal CA1 region of Shank3 (Δ9) mice exhibited reduced excitatory transmission at Schaffer collateral synapses and increased frequency of spontaneous inhibitory synaptic events in pyramidal neurons. In contrast, prelimbic layer 2/3 pyramidal neurons in the medial prefrontal cortex displayed decreased frequency of spontaneous inhibitory synaptic events, indicating alterations in the ratio of excitation/inhibition (E/I ratio) in the Shank3 (Δ9) brain. These mice displayed a mild increase in rearing in a novel environment and mildly impaired spatial memory, but showed normal social interaction and repetitive behavior. These results suggest that ankyrin repeat-containing Shank3 splice variants are important for E/I balance, rearing behavior, and spatial memory.
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Affiliation(s)
- Jiseok Lee
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology Daejeon, South Korea
| | - Changuk Chung
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology Daejeon, South Korea
| | - Seungmin Ha
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology Daejeon, South Korea
| | - Dongmin Lee
- Department of Anatomy and Division of Brain Korea 21, Biomedical Science, College of Medicine, Korea University Seoul, South Korea
| | - Do-Young Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology Daejeon, South Korea
| | - Hyun Kim
- Department of Anatomy and Division of Brain Korea 21, Biomedical Science, College of Medicine, Korea University Seoul, South Korea
| | - Eunjoon Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology Daejeon, South Korea ; Center for Synaptic Brain Dysfunctions, Institute for Basic Science Daejeon, South Korea
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Tao-Cheng JH, Yang Y, Reese TS, Dosemeci A. Differential distribution of Shank and GKAP at the postsynaptic density. PLoS One 2015; 10:e0118750. [PMID: 25775468 PMCID: PMC4361712 DOI: 10.1371/journal.pone.0118750] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Accepted: 01/06/2015] [Indexed: 11/18/2022] Open
Abstract
Shank and GKAP are scaffold proteins and binding partners at the postsynaptic density (PSD). The distribution and dynamics of Shank and GKAP were studied in dissociated hippocampal cultures by pre-embedding immunogold electron microscopy. Antibodies against epitopes containing their respective mutual binding sites were used to verify the expected juxtapositioning of Shank and GKAP. If all Shank and GKAP molecules at the PSD were bound to each other, the distribution of label for the two proteins should coincide. However, labels for the mutual binding sites showed significant differences in distribution, with a narrow distribution for GKAP located close to the postsynaptic membrane, and a wider distribution for Shank extending deeper into the cytoplasm. Upon depolarization with high K+, neither the intensity nor distribution of label for GKAP changed, but labeling intensity for Shank at the PSD increased to ~150% of controls while the median distance of label from postsynaptic membrane increased by 7.5 nm. These results indicate a preferential recruitment of Shank to more distal parts of the PSD complex. Conversely, upon incubation in Ca2+-free medium containing EGTA, the labeling intensity of Shank at the PSD decreased to ~70% of controls and the median distance of label from postsynaptic membrane decreased by 9 nm, indicating a preferential loss of Shank molecules in more distal parts of the PSD complex. These observations identify two pools of Shank at the PSD complex, one relatively stable pool, closer to the postsynaptic membrane that can bind to GKAP, and another more dynamic pool at a location too far away to bind to GKAP.
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Affiliation(s)
- Jung-Hwa Tao-Cheng
- EM Facility, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, United States of America
- * E-mail:
| | - Yijung Yang
- Laboratory of Neurobiology, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Thomas S. Reese
- Laboratory of Neurobiology, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Ayse Dosemeci
- Laboratory of Neurobiology, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, United States of America
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Rudy CC, Hunsberger HC, Weitzner DS, Reed MN. The role of the tripartite glutamatergic synapse in the pathophysiology of Alzheimer's disease. Aging Dis 2015; 6:131-48. [PMID: 25821641 PMCID: PMC4365957 DOI: 10.14336/ad.2014.0423] [Citation(s) in RCA: 105] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2014] [Accepted: 04/23/2014] [Indexed: 12/26/2022] Open
Abstract
Alzheimer's disease (AD) is the most common form of dementia in individuals over 65 years of age and is characterized by accumulation of beta-amyloid (Aβ) and tau. Both Aβ and tau alter synaptic plasticity, leading to synapse loss, neural network dysfunction, and eventually neuron loss. However, the exact mechanism by which these proteins cause neurodegeneration is still not clear. A growing body of evidence suggests perturbations in the glutamatergic tripartite synapse, comprised of a presynaptic terminal, a postsynaptic spine, and an astrocytic process, may underlie the pathogenic mechanisms of AD. Glutamate is the primary excitatory neurotransmitter in the brain and plays an important role in learning and memory, but alterations in glutamatergic signaling can lead to excitotoxicity. This review discusses the ways in which both beta-amyloid (Aβ) and tau act alone and in concert to perturb synaptic functioning of the tripartite synapse, including alterations in glutamate release, astrocytic uptake, and receptor signaling. Particular emphasis is given to the role of N-methyl-D-aspartate (NMDA) as a possible convergence point for Aβ and tau toxicity.
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Affiliation(s)
- Carolyn C. Rudy
- Behavioral Neuroscience, Department of Psychology, West Virginia University, Morgantown, WV, 26506, USA
| | - Holly C. Hunsberger
- Behavioral Neuroscience, Department of Psychology, West Virginia University, Morgantown, WV, 26506, USA
| | - Daniel S. Weitzner
- Behavioral Neuroscience, Department of Psychology, West Virginia University, Morgantown, WV, 26506, USA
| | - Miranda N. Reed
- Behavioral Neuroscience, Department of Psychology, West Virginia University, Morgantown, WV, 26506, USA
- Center for Neuroscience, West Virginia University, Morgantown, WV, 26506, USA
- Center for Basic and Translational Stroke Research, West Virginia University, Morgantown, WV, 26506, USA
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50
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Pandey SP, Rai R, Gaur P, Prasad S. Development- and age-related alterations in the expression of AMPA receptor subunit GluR2 and its trafficking proteins in the hippocampus of male mouse brain. Biogerontology 2015; 16:317-28. [DOI: 10.1007/s10522-014-9548-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2014] [Accepted: 12/16/2014] [Indexed: 10/24/2022]
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