1
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Sun SY, Nie L, Zhang J, Fang X, Luo H, Fu C, Wei Z, Tang AH. The interaction between KIF21A and KANK1 regulates dendritic morphology and synapse plasticity in neurons. Neural Regen Res 2025; 20:209-223. [PMID: 38767486 PMCID: PMC11246154 DOI: 10.4103/1673-5374.391301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2023] [Accepted: 11/07/2023] [Indexed: 05/22/2024] Open
Abstract
JOURNAL/nrgr/04.03/01300535-202501000-00029/figure1/v/2024-05-14T021156Z/r/image-tiff Morphological alterations in dendritic spines have been linked to changes in functional communication between neurons that affect learning and memory. Kinesin-4 KIF21A helps organize the microtubule-actin network at the cell cortex by interacting with KANK1; however, whether KIF21A modulates dendritic structure and function in neurons remains unknown. In this study, we found that KIF21A was distributed in a subset of dendritic spines, and that these KIF21A-positive spines were larger and more structurally plastic than KIF21A-negative spines. Furthermore, the interaction between KIF21A and KANK1 was found to be critical for dendritic spine morphogenesis and synaptic plasticity. Knockdown of either KIF21A or KANK1 inhibited dendritic spine morphogenesis and dendritic branching, and these deficits were fully rescued by coexpressing full-length KIF21A or KANK1, but not by proteins with mutations disrupting direct binding between KIF21A and KANK1 or binding between KANK1 and talin1. Knocking down KIF21A in the hippocampus of rats inhibited the amplitudes of long-term potentiation induced by high-frequency stimulation and negatively impacted the animals' cognitive abilities. Taken together, our findings demonstrate the function of KIF21A in modulating spine morphology and provide insight into its role in synaptic function.
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Affiliation(s)
- Shi-Yan Sun
- Hefei National Research Center for Physical Sciences at the Microscale, CAS Key Laboratory of Brain Function and Disease, Ministry of Education Key Laboratory for Membrane-less Organelles and Cellular Dynamics, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui Province, China
- Institute of Artificial Intelligence, Hefei Comprehensive National Science Center, Hefei, Anhui Province, China
| | - Lingyun Nie
- Hefei National Research Center for Physical Sciences at the Microscale, CAS Key Laboratory of Brain Function and Disease, Ministry of Education Key Laboratory for Membrane-less Organelles and Cellular Dynamics, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui Province, China
- CAS Center for Excellence in Molecular Cell Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui Province, China
| | - Jing Zhang
- Department of Neurobiology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong Province, China
- Brain Research Center, Southern University of Science and Technology, Shenzhen, Guangdong Province, China
| | - Xue Fang
- Hefei National Research Center for Physical Sciences at the Microscale, CAS Key Laboratory of Brain Function and Disease, Ministry of Education Key Laboratory for Membrane-less Organelles and Cellular Dynamics, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui Province, China
| | - Hongmei Luo
- Hefei National Research Center for Physical Sciences at the Microscale, CAS Key Laboratory of Brain Function and Disease, Ministry of Education Key Laboratory for Membrane-less Organelles and Cellular Dynamics, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui Province, China
- Institute of Artificial Intelligence, Hefei Comprehensive National Science Center, Hefei, Anhui Province, China
| | - Chuanhai Fu
- Hefei National Research Center for Physical Sciences at the Microscale, CAS Key Laboratory of Brain Function and Disease, Ministry of Education Key Laboratory for Membrane-less Organelles and Cellular Dynamics, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui Province, China
- CAS Center for Excellence in Molecular Cell Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui Province, China
| | - Zhiyi Wei
- Department of Neurobiology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong Province, China
- Brain Research Center, Southern University of Science and Technology, Shenzhen, Guangdong Province, China
| | - Ai-Hui Tang
- Hefei National Research Center for Physical Sciences at the Microscale, CAS Key Laboratory of Brain Function and Disease, Ministry of Education Key Laboratory for Membrane-less Organelles and Cellular Dynamics, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui Province, China
- Institute of Artificial Intelligence, Hefei Comprehensive National Science Center, Hefei, Anhui Province, China
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2
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Gatford NJF, Deans PJM, Duarte RRR, Chennell G, Sellers KJ, Raval P, Srivastava DP. Neuroligin-3 and neuroligin-4X form nanoscopic clusters and regulate growth cone organization and size. Hum Mol Genet 2022; 31:674-691. [PMID: 34542148 PMCID: PMC8895740 DOI: 10.1093/hmg/ddab277] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 08/25/2021] [Accepted: 09/13/2021] [Indexed: 12/01/2022] Open
Abstract
The cell-adhesion proteins neuroligin-3 and neuroligin-4X (NLGN3/4X) have well described roles in synapse formation. NLGN3/4X are also expressed highly during neurodevelopment. However, the role these proteins play during this period is unknown. Here we show that NLGN3/4X localized to the leading edge of growth cones where it promoted neuritogenesis in immature human neurons. Super-resolution microscopy revealed that NLGN3/4X clustering induced growth cone enlargement and influenced actin filament organization. Critically, these morphological effects were not induced by autism spectrum disorder (ASD)-associated NLGN3/4X variants. Finally, actin regulators p21-activated kinase 1 and cofilin were found to be activated by NLGN3/4X and involved in mediating the effects of these adhesion proteins on actin filaments, growth cones and neuritogenesis. These data reveal a novel role for NLGN3 and NLGN4X in the development of neuronal architecture, which may be altered in the presence of ASD-associated variants.
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Affiliation(s)
- Nicholas J F Gatford
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology, & Neuroscience, King's College London, London, UK
- MRC Centre for Neurodevelopmental Disorders, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - P J Michael Deans
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology, & Neuroscience, King's College London, London, UK
- MRC Centre for Neurodevelopmental Disorders, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Rodrigo R R Duarte
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology, & Neuroscience, King's College London, London, UK
| | - George Chennell
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology, & Neuroscience, King's College London, London, UK
| | - Katherine J Sellers
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology, & Neuroscience, King's College London, London, UK
| | - Pooja Raval
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology, & Neuroscience, King's College London, London, UK
- MRC Centre for Neurodevelopmental Disorders, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Deepak P Srivastava
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology, & Neuroscience, King's College London, London, UK
- MRC Centre for Neurodevelopmental Disorders, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
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3
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Motz CT, Kabat V, Saxena T, Bellamkonda RV, Zhu C. Neuromechanobiology: An Expanding Field Driven by the Force of Greater Focus. Adv Healthc Mater 2021; 10:e2100102. [PMID: 34342167 PMCID: PMC8497434 DOI: 10.1002/adhm.202100102] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Revised: 07/06/2021] [Indexed: 12/14/2022]
Abstract
The brain processes information by transmitting signals through highly connected and dynamic networks of neurons. Neurons use specific cellular structures, including axons, dendrites and synapses, and specific molecules, including cell adhesion molecules, ion channels and chemical receptors to form, maintain and communicate among cells in the networks. These cellular and molecular processes take place in environments rich of mechanical cues, thus offering ample opportunities for mechanical regulation of neural development and function. Recent studies have suggested the importance of mechanical cues and their potential regulatory roles in the development and maintenance of these neuronal structures. Also suggested are the importance of mechanical cues and their potential regulatory roles in the interaction and function of molecules mediating the interneuronal communications. In this review, the current understanding is integrated and promising future directions of neuromechanobiology are suggested at the cellular and molecular levels. Several neuronal processes where mechanics likely plays a role are examined and how forces affect ligand binding, conformational change, and signal induction of molecules key to these neuronal processes are indicated, especially at the synapse. The disease relevance of neuromechanobiology as well as therapies and engineering solutions to neurological disorders stemmed from this emergent field of study are also discussed.
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Affiliation(s)
- Cara T Motz
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, 30332-0363, USA
- Parker H. Petit Institute for Bioengineering and Biosciences, Georgia Institute of Technology, Atlanta, GA, 30332-0363, USA
| | - Victoria Kabat
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, 30332-0363, USA
| | - Tarun Saxena
- Department of Biomedical Engineering, Duke University, Durham, NC, 27709, USA
| | - Ravi V Bellamkonda
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, 27708, USA
| | - Cheng Zhu
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, 30332-0363, USA
- Parker H. Petit Institute for Bioengineering and Biosciences, Georgia Institute of Technology, Atlanta, GA, 30332-0363, USA
- George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, 30332-0363, USA
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4
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Liouta K, Chabbert J, Benquet S, Tessier B, Studer V, Sainlos M, De Wit J, Thoumine O, Chamma I. Role of regulatory C-terminal motifs in synaptic confinement of LRRTM2. Biol Cell 2021; 113:492-506. [PMID: 34498765 DOI: 10.1111/boc.202100026] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 08/30/2021] [Accepted: 09/01/2021] [Indexed: 12/25/2022]
Abstract
Leucine Rich Repeat Transmembrane proteins (LRRTMs) are neuronal cell adhesion molecules involved in synapse development and plasticity. LRRTM2 is the most synaptogenic isoform of the family, and its expression is strongly restricted to excitatory synapses in mature neurons. However, the mechanisms by which LRRTM2 is trafficked and stabilized at synapses remain unknown. Here, we examine the role of LRRTM2 intracellular domain on its membrane expression and stabilization at excitatory synapses, using a knock-down strategy combined to single molecule tracking and super-resolution dSTORM microscopy. We show that LRRTM2 operates an important shift in mobility after synaptogenesis in hippocampal neurons. Knock-down of LRRTM2 during synapse formation reduced excitatory synapse density in mature neurons. Deletion of LRRTM2 C-terminal domain abolished the compartmentalization of LRRTM2 in dendrites and disrupted its synaptic enrichment. Furtheremore, we show that LRRTM2 diffusion is increased in the absence of its intracellular domain, and that the protein is more dispersed at synapses. Surprisingly, LRRTM2 confinement at synapses was strongly dependent on a YxxC motif in the C-terminal domain, but was independent of the PDZ-like binding motif ECEV. Finally, the nanoscale organization of LRRTM2 at excitatory synapses depended on its C-terminal domain, with involvement of both the PDZ-binding and YxxC motifs. Altogether, these results demonstrate that LRRTM2 trafficking and enrichment at excitatory synapses are dependent on its intracellular domain.
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Affiliation(s)
- Konstantina Liouta
- Interdisciplinary Institute for Neuroscience, Centre National de la Recherche Scientifique, Bordeaux, France.,Interdisciplinary Institute for Neuroscience, University of Bordeaux, Bordeaux, France
| | - Julia Chabbert
- Interdisciplinary Institute for Neuroscience, Centre National de la Recherche Scientifique, Bordeaux, France.,Interdisciplinary Institute for Neuroscience, University of Bordeaux, Bordeaux, France
| | - Sebastien Benquet
- Interdisciplinary Institute for Neuroscience, Centre National de la Recherche Scientifique, Bordeaux, France.,Interdisciplinary Institute for Neuroscience, University of Bordeaux, Bordeaux, France
| | - Béatrice Tessier
- Interdisciplinary Institute for Neuroscience, Centre National de la Recherche Scientifique, Bordeaux, France.,Interdisciplinary Institute for Neuroscience, University of Bordeaux, Bordeaux, France
| | - Vincent Studer
- Interdisciplinary Institute for Neuroscience, Centre National de la Recherche Scientifique, Bordeaux, France.,Interdisciplinary Institute for Neuroscience, University of Bordeaux, Bordeaux, France
| | - Matthieu Sainlos
- Interdisciplinary Institute for Neuroscience, Centre National de la Recherche Scientifique, Bordeaux, France.,Interdisciplinary Institute for Neuroscience, University of Bordeaux, Bordeaux, France
| | - Joris De Wit
- VIB Center for Brain & Disease Research, Leuven, Belgium.,KU Leuven, Department of Neurosciences, Leuven Brain Institute, Leuven, Belgium
| | - Olivier Thoumine
- Interdisciplinary Institute for Neuroscience, Centre National de la Recherche Scientifique, Bordeaux, France.,Interdisciplinary Institute for Neuroscience, University of Bordeaux, Bordeaux, France
| | - Ingrid Chamma
- Interdisciplinary Institute for Neuroscience, Centre National de la Recherche Scientifique, Bordeaux, France.,Interdisciplinary Institute for Neuroscience, University of Bordeaux, Bordeaux, France
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5
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Chowdhury D, Watters K, Biederer T. Synaptic recognition molecules in development and disease. Curr Top Dev Biol 2021; 142:319-370. [PMID: 33706921 DOI: 10.1016/bs.ctdb.2020.12.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Synaptic connectivity patterns underlie brain functions. How recognition molecules control where and when neurons form synapses with each other, therefore, is a fundamental question of cellular neuroscience. This chapter delineates adhesion and signaling complexes as well as secreted factors that contribute to synaptic partner recognition in the vertebrate brain. The sections follow a developmental perspective and discuss how recognition molecules (1) guide initial synaptic wiring, (2) provide for the rejection of incorrect partner choices, (3) contribute to synapse specification, and (4) support the removal of inappropriate synapses once formed. These processes involve a rich repertoire of molecular players and key protein families are described, notably the Cadherin and immunoglobulin superfamilies, Semaphorins/Plexins, Leucine-rich repeat containing proteins, and Neurexins and their binding partners. Molecular themes that diversify these recognition systems are defined and highlighted throughout the text, including the neuron-type specific expression and combinatorial action of recognition factors, alternative splicing, and post-translational modifications. Methodological innovations advancing the field such as proteomic approaches and single cell expression studies are additionally described. Further, the chapter highlights the importance of choosing an appropriate brain region to analyze synaptic recognition factors and the advantages offered by laminated structures like the hippocampus or retina. In a concluding section, the profound disease relevance of aberrant synaptic recognition for neurodevelopmental and psychiatric disorders is discussed. Based on the current progress, an outlook is presented on research goals that can further advance insights into how recognition molecules provide for the astounding precision and diversity of synaptic connections.
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Affiliation(s)
| | - Katherine Watters
- Department of Neurology, Yale School of Medicine, New Haven, CT, United States; Neuroscience Graduate Program, Tufts University School of Medicine, Boston, MA, United States
| | - Thomas Biederer
- Department of Neurology, Yale School of Medicine, New Haven, CT, United States.
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6
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Li Y, Yi J, Liu W, Liu Y, Liu J. Gaining insight into cellular cardiac physiology using single particle tracking. J Mol Cell Cardiol 2020; 148:63-77. [PMID: 32871158 DOI: 10.1016/j.yjmcc.2020.08.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 08/18/2020] [Accepted: 08/20/2020] [Indexed: 11/29/2022]
Abstract
Single particle tracking (SPT) is a robust technique to monitor single-molecule behaviors in living cells directly. By this approach, we can uncover the potential biological significance of particle dynamics by statistically characterizing individual molecular behaviors. SPT provides valuable information at the single-molecule level, that could be obscured by simple averaging that is inherent to conventional ensemble measurements. Here, we give a brief introduction to SPT including the commonly used optical implementations, fluorescence labeling strategies, and data analysis methods. We then focus on how SPT has been harnessed to decipher myocardial function. In this context, SPT has provided novel insight into the lateral diffusion of signal receptors and ion channels, the dynamic organization of cardiac nanodomains, subunit composition and stoichiometry of cardiac ion channels, myosin movement along actin filaments, the kinetic features of transcription factors involved in cardiac remodeling, and the intercellular communication by nanotubes. Finally, we speculate on the prospects and challenges of applying SPT to future questions regarding cellular cardiac physiology using SPT.
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Affiliation(s)
- Ying Li
- School of Basic Medical Sciences, Shenzhen University Health Science Center, Shenzhen, 518060, China.
| | - Jing Yi
- School of Basic Medical Sciences, Shenzhen University Health Science Center, Shenzhen, 518060, China.
| | - Wenjuan Liu
- School of Basic Medical Sciences, Shenzhen University Health Science Center, Shenzhen, 518060, China.
| | - Yun Liu
- The Seventh Affiliated Hospital, Sun Yat-sen University, Guangdong Province, China.
| | - Jie Liu
- School of Basic Medical Sciences, Shenzhen University Health Science Center, Shenzhen, 518060, China.
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7
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Hasegawa S, Imai M, Yamasaki M, Takahashi N. Isolation and characterization of human acetoacetyl-CoA synthetase splice variants. GENE REPORTS 2020. [DOI: 10.1016/j.genrep.2020.100665] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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8
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Dagar S, Gottmann K. Differential Properties of the Synaptogenic Activities of the Neurexin Ligands Neuroligin1 and LRRTM2. Front Mol Neurosci 2019; 12:269. [PMID: 31780894 PMCID: PMC6856695 DOI: 10.3389/fnmol.2019.00269] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Accepted: 10/22/2019] [Indexed: 12/03/2022] Open
Abstract
Synaptic cell adhesion molecules are well established to exhibit synaptogenic activity when overexpressed in target cells, indicating that they are involved in formation and functional maturation of synapses. The postsynaptic adhesion proteins Neuroligin1 and LRRTM2 both induce synaptic vesicle clusters in presynaptic axons in vitro by transsynaptically interacting with neurexins. In neurons, this is accompanied by the induction of glutamatergic, but not GABAergic synapses. Although the synaptogenic activity of Neuroligin1 has been well characterized, the properties of the synaptogenic activities of other synaptic adhesion molecules are largely unknown. In this paper, we now compared characteristics of the synaptogenic activities of Neuroligin1 and LRRTM2 upon overexpression in cultured mouse cortical neurons. Individual cortical neurons were transfected with Neuroligin1 and LRRTM2 expression plasmids, respectively, and synaptic vesicle clustering in contacting axons was examined by immunostaining for the vesicle membrane protein VAMP2. In immature neurons at 6–7 days in vitro (DIV) both Neuroligin1 and LRRTM2 exhibited strong synaptogenic activity. However, upon further neuronal differentiation only LRRTM2 retained significant synaptogenic activity at 12–13 DIV. A similar differential developmental maturation of the synaptogenic activities of Neuroligin1 and LRRTM2 was observed for the induction of glutamatergic synapses, which were detected by co-immunostaining for VGLUT1 and Homer1. Most interestingly, the synaptogenic activity of Neuroligin1 was strongly dependent on the expression and function of the synaptic adhesion molecule N-cadherin in immature neurons. In contrast, the synaptogenic activity of LRRTM2 was independent of N-cadherin expression and function in both immature (6–7 DIV) and more mature neurons (14–15 DIV). Taken together, our results with overexpression in cultured cortical neurons revealed striking differences in the properties of the synaptogenic activities of Neuroligin1 and LRRTM2, although both transsynaptically interact with presynaptic neurexins.
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Affiliation(s)
- Sushma Dagar
- Institute of Neuro- and Sensory Physiology, Medical Faculty, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Kurt Gottmann
- Institute of Neuro- and Sensory Physiology, Medical Faculty, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
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9
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Metzbower SR, Joo Y, Benavides DR, Blanpied TA. Properties of Individual Hippocampal Synapses Influencing NMDA-Receptor Activation by Spontaneous Neurotransmission. eNeuro 2019; 6:ENEURO.0419-18.2019. [PMID: 31110134 PMCID: PMC6541874 DOI: 10.1523/eneuro.0419-18.2019] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Revised: 05/05/2019] [Accepted: 05/12/2019] [Indexed: 12/14/2022] Open
Abstract
NMDA receptor (NMDAR) activation is critical for maintenance and modification of synapse strength. Specifically, NMDAR activation by spontaneous glutamate release has been shown to mediate some forms of synaptic plasticity as well as synaptic development. Interestingly, there is evidence that within individual synapses each release mode may be segregated such that postsynaptically there are distinct pools of responsive receptors. To examine potential regulators of NMDAR activation because of spontaneous glutamate release in cultured hippocampal neurons, we used GCaMP6f imaging at single synapses in concert with confocal and super-resolution imaging. Using these single-spine approaches, we found that Ca2+ entry activated by spontaneous release tends to be carried by GluN2B-NMDARs. Additionally, the amount of NMDAR activation varies greatly both between synapses and within synapses, and is unrelated to spine and synapse size, but does correlate loosely with synapse distance from the soma. Despite the critical role of spontaneous activation of NMDARs in maintaining synaptic function, their activation seems to be controlled factors other than synapse size or synapse distance from the soma. It is most likely that NMDAR activation by spontaneous release influenced variability in subsynaptic receptor position, release site position, vesicle content, and channel properties. Therefore, spontaneous activation of NMDARs appears to be regulated distinctly from other receptor types, notably AMPARs, within individual synapses.
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Affiliation(s)
| | - Yuyoung Joo
- Department of Neurology, University of Maryland School of Medicine, Baltimore, Maryland, 21201
| | - David R Benavides
- Department of Neurology, University of Maryland School of Medicine, Baltimore, Maryland, 21201
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10
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Wrackmeyer U, Kaldrack J, Jüttner R, Pannasch U, Gimber N, Freiberg F, Purfürst B, Kainmueller D, Schmitz D, Haucke V, Rathjen FG, Gotthardt M. The cell adhesion protein CAR is a negative regulator of synaptic transmission. Sci Rep 2019; 9:6768. [PMID: 31043663 PMCID: PMC6494904 DOI: 10.1038/s41598-019-43150-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Accepted: 04/17/2019] [Indexed: 11/09/2022] Open
Abstract
The Coxsackievirus and adenovirus receptor (CAR) is essential for normal electrical conductance in the heart, but its role in the postnatal brain is largely unknown. Using brain specific CAR knockout mice (KO), we discovered an unexpected role of CAR in neuronal communication. This includes increased basic synaptic transmission at hippocampal Schaffer collaterals, resistance to fatigue, and enhanced long-term potentiation. Spontaneous neurotransmitter release and speed of endocytosis are increased in KOs, accompanied by increased expression of the exocytosis associated calcium sensor synaptotagmin 2. Using proximity proteomics and binding studies, we link CAR to the exocytosis machinery as it associates with syntenin and synaptobrevin/VAMP2 at the synapse. Increased synaptic function does not cause adverse effects in KO mice, as behavior and learning are unaffected. Thus, unlike the connexin-dependent suppression of atrioventricular conduction in the cardiac knockout, communication in the CAR deficient brain is improved, suggesting a role for CAR in presynaptic processes.
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Affiliation(s)
- Uta Wrackmeyer
- Neuromuscular and Cardiovascular Cell Biology, Max Delbrück Center for Molecular Medicine, 13125, Berlin, Germany
| | - Joanna Kaldrack
- Neuromuscular and Cardiovascular Cell Biology, Max Delbrück Center for Molecular Medicine, 13125, Berlin, Germany
| | - René Jüttner
- Neuromuscular and Cardiovascular Cell Biology, Max Delbrück Center for Molecular Medicine, 13125, Berlin, Germany.,Developmental Neurobiology, Max Delbrück Center for Molecular Medicine, 13125, Berlin, Germany
| | - Ulrike Pannasch
- Neuroscience Research Center, Cluster of Excellence NeuroCure, Charité, 10117, Berlin, Germany
| | - Niclas Gimber
- Department of Molecular Pharmacology and Cell Biology, Leibniz Forschungsinstitut für Molekulare Pharmakologie (FMP), 13125, Berlin, Germany
| | - Fabian Freiberg
- Neuromuscular and Cardiovascular Cell Biology, Max Delbrück Center for Molecular Medicine, 13125, Berlin, Germany
| | - Bettina Purfürst
- Core Facility Electron Microscopy, Max Delbrück Center for Molecular Medicine, 13125, Berlin, Germany
| | - Dagmar Kainmueller
- Biomedical Image Analysis, Max Delbrück Center for Molecular Medicine and Berlin Institute of Health, 13125, Berlin, Germany
| | - Dietmar Schmitz
- Neuroscience Research Center, Cluster of Excellence NeuroCure, Charité, 10117, Berlin, Germany
| | - Volker Haucke
- Department of Molecular Pharmacology and Cell Biology, Leibniz Forschungsinstitut für Molekulare Pharmakologie (FMP), 13125, Berlin, Germany
| | - Fritz G Rathjen
- Developmental Neurobiology, Max Delbrück Center for Molecular Medicine, 13125, Berlin, Germany
| | - Michael Gotthardt
- Neuromuscular and Cardiovascular Cell Biology, Max Delbrück Center for Molecular Medicine, 13125, Berlin, Germany.
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11
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Kilinc D. The Emerging Role of Mechanics in Synapse Formation and Plasticity. Front Cell Neurosci 2018; 12:483. [PMID: 30574071 PMCID: PMC6291423 DOI: 10.3389/fncel.2018.00483] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2018] [Accepted: 11/27/2018] [Indexed: 12/26/2022] Open
Abstract
The regulation of synaptic strength forms the basis of learning and memory, and is a key factor in understanding neuropathological processes that lead to cognitive decline and dementia. While the mechanical aspects of neuronal development, particularly during axon growth and guidance, have been extensively studied, relatively little is known about the mechanical aspects of synapse formation and plasticity. It is established that a filamentous actin network with complex spatiotemporal behavior controls the dendritic spine shape and size, which is thought to be crucial for activity-dependent synapse plasticity. Accordingly, a number of actin binding proteins have been identified as regulators of synapse plasticity. On the other hand, a number of cell adhesion molecules (CAMs) are found in synapses, some of which form transsynaptic bonds to align the presynaptic active zone (PAZ) with the postsynaptic density (PSD). Considering that these CAMs are key components of cellular mechanotransduction, two critical questions emerge: (i) are synapses mechanically regulated? and (ii) does disrupting the transsynaptic force balance lead to (or exacerbate) synaptic failure? In this mini review article, I will highlight the mechanical aspects of synaptic structures-focusing mainly on cytoskeletal dynamics and CAMs-and discuss potential mechanoregulation of synapses and its relevance to neurodegenerative diseases.
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Affiliation(s)
- Devrim Kilinc
- INSERM U1167, Institut Pasteur de Lille, Lille, France
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12
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Gorlewicz A, Kaczmarek L. Pathophysiology of Trans-Synaptic Adhesion Molecules: Implications for Epilepsy. Front Cell Dev Biol 2018; 6:119. [PMID: 30298130 PMCID: PMC6160742 DOI: 10.3389/fcell.2018.00119] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2018] [Accepted: 08/30/2018] [Indexed: 12/31/2022] Open
Abstract
Chemical synapses are specialized interfaces between neurons in the brain that transmit and modulate information, thereby integrating cells into multiplicity of interacting neural circuits. Cell adhesion molecules (CAMs) might form trans-synaptic complexes that are crucial for the appropriate identification of synaptic partners and further for the establishment, properties, and dynamics of synapses. When affected, trans-synaptic adhesion mechanisms play a role in synaptopathies in a variety of neuropsychiatric disorders including epilepsy. This review recapitulates current understanding of trans-synaptic interactions in pathophysiology of interneuronal connections. In particular, we discuss here the possible implications of trans-synaptic adhesion dysfunction for epilepsy.
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Affiliation(s)
- Adam Gorlewicz
- Laboratory of Neurobiology, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland
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