1
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Aksan B, Kenkel AK, Yan J, Sánchez Romero J, Missirlis D, Mauceri D. VEGFD signaling balances stability and activity-dependent structural plasticity of dendrites. Cell Mol Life Sci 2024; 81:354. [PMID: 39158743 PMCID: PMC11335284 DOI: 10.1007/s00018-024-05357-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2024] [Revised: 07/08/2024] [Accepted: 07/09/2024] [Indexed: 08/20/2024]
Abstract
Mature neurons have stable dendritic architecture, which is essential for the nervous system to operate correctly. The ability to undergo structural plasticity, required to support adaptive processes like memory formation, is still present in mature neurons. It is unclear what molecular and cellular processes control this delicate balance between dendritic structural plasticity and stabilization. Failures in the preservation of optimal dendrite structure due to atrophy or maladaptive plasticity result in abnormal connectivity and are associated with various neurological diseases. Vascular endothelial growth factor D (VEGFD) is critical for the maintenance of mature dendritic trees. Here, we describe how VEGFD affects the neuronal cytoskeleton and demonstrate that VEGFD exerts its effects on dendrite stabilization by influencing the actin cortex and reducing microtubule dynamics. Further, we found that during synaptic activity-induced structural plasticity VEGFD is downregulated. Our findings revealed that VEGFD, acting on its cognate receptor VEGFR3, opposes structural changes by negatively regulating dendrite growth in cultured hippocampal neurons and in vivo in the adult mouse hippocampus with consequences on memory formation. A phosphoproteomic screening identified several regulatory proteins of the cytoskeleton modulated by VEGFD. Among the actin cortex-associated proteins, we found that VEGFD induces dephosphorylation of ezrin at tyrosine 478 via activation of the striatal-enriched protein tyrosine phosphatase (STEP). Activity-triggered structural plasticity of dendrites was impaired by expression of a phospho-deficient mutant ezrin in vitro and in vivo. Thus, VEGFD governs the equilibrium between stabilization and plasticity of dendrites by acting as a molecular brake of structural remodeling.
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Affiliation(s)
- Bahar Aksan
- Department of Neurobiology, Interdisciplinary Centre for Neurosciences (IZN), Heidelberg University, INF 366, 69120, Heidelberg, Germany
| | - Ann-Kristin Kenkel
- Department of Neurobiology, Interdisciplinary Centre for Neurosciences (IZN), Heidelberg University, INF 366, 69120, Heidelberg, Germany
| | - Jing Yan
- Department of Neurobiology, Interdisciplinary Centre for Neurosciences (IZN), Heidelberg University, INF 366, 69120, Heidelberg, Germany
| | - Javier Sánchez Romero
- Department of Neurobiology, Interdisciplinary Centre for Neurosciences (IZN), Heidelberg University, INF 366, 69120, Heidelberg, Germany
| | - Dimitris Missirlis
- Department of Cellular Biophysics, Max-Planck-Institute for Medical Research, Jahnstraße 29, 69120, Heidelberg, Germany
| | - Daniela Mauceri
- Department of Neurobiology, Interdisciplinary Centre for Neurosciences (IZN), Heidelberg University, INF 366, 69120, Heidelberg, Germany.
- Department Molecular and Cellular Neuroscience, Institute of Anatomy and Cell Biology, University of Marburg, Robert-Koch-Str. 8, 35032, Marburg, Germany.
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2
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Verdys P, Rey Barroso J, Girel A, Vermeil J, Bergert M, Sanchez T, Métais A, Mangeat T, Bellard E, Bigot C, Astarie-Dequeker C, Labrousse A, Girard JP, Maridonneau-Parini I, Vérollet C, Lagarrigue F, Diz-Muñoz A, Heuvingh J, Piel M, du Roure O, Le Cabec V, Carréno S, Poincloux R. Ezrin, radixin, and moesin are dispensable for macrophage migration and cellular cortex mechanics. EMBO J 2024:10.1038/s44318-024-00173-7. [PMID: 39026000 DOI: 10.1038/s44318-024-00173-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Revised: 06/17/2024] [Accepted: 07/01/2024] [Indexed: 07/20/2024] Open
Abstract
The cellular cortex provides crucial mechanical support and plays critical roles during cell division and migration. The proteins of the ERM family, comprised of ezrin, radixin, and moesin, are central to these processes by linking the plasma membrane to the actin cytoskeleton. To investigate the contributions of the ERM proteins to leukocyte migration, we generated single and triple ERM knockout macrophages. Surprisingly, we found that even in the absence of ERM proteins, macrophages still form the different actin structures promoting cell migration, such as filopodia, lamellipodia, podosomes, and ruffles. Furthermore, we discovered that, unlike every other cell type previously investigated, the single or triple knockout of ERM proteins does not affect macrophage migration in diverse contexts. Finally, we demonstrated that the loss of ERMs in macrophages does not affect the mechanical properties of their cortex. These findings challenge the notion that ERMs are universally essential for cortex mechanics and cell migration and support the notion that the macrophage cortex may have diverged from that of other cells to allow for their uniquely adaptive cortical plasticity.
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Affiliation(s)
- Perrine Verdys
- Institut de Pharmacologie et de Biologie Structurale (IPBS), Université de Toulouse, CNRS, Université Toulouse III - Paul Sabatier (UT3), Toulouse, France
- Institut de Recherche en Immunologie et en Cancérologie (IRIC), Université de Montréal, Montréal, Canada
| | - Javier Rey Barroso
- Institut de Pharmacologie et de Biologie Structurale (IPBS), Université de Toulouse, CNRS, Université Toulouse III - Paul Sabatier (UT3), Toulouse, France
| | - Adeline Girel
- Institut de Pharmacologie et de Biologie Structurale (IPBS), Université de Toulouse, CNRS, Université Toulouse III - Paul Sabatier (UT3), Toulouse, France
| | - Joseph Vermeil
- PMMH, ESPCI Paris, PSL University, CNRS, Université Paris Cité, Sorbonne Université, Paris, France
| | - Martin Bergert
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Thibaut Sanchez
- Institut de Pharmacologie et de Biologie Structurale (IPBS), Université de Toulouse, CNRS, Université Toulouse III - Paul Sabatier (UT3), Toulouse, France
| | - Arnaud Métais
- Institut de Pharmacologie et de Biologie Structurale (IPBS), Université de Toulouse, CNRS, Université Toulouse III - Paul Sabatier (UT3), Toulouse, France
| | - Thomas Mangeat
- LITC Core Facility, Centre de Biologie Intégrative, Université de Toulouse, CNRS, UPS, 31062, Toulouse, France
| | - Elisabeth Bellard
- Institut de Pharmacologie et de Biologie Structurale (IPBS), Université de Toulouse, CNRS, Université Toulouse III - Paul Sabatier (UT3), Toulouse, France
- Equipe Labellisée Ligue Contre le Cancer, Paris, France
| | - Claire Bigot
- Institut de Pharmacologie et de Biologie Structurale (IPBS), Université de Toulouse, CNRS, Université Toulouse III - Paul Sabatier (UT3), Toulouse, France
| | - Catherine Astarie-Dequeker
- Institut de Pharmacologie et de Biologie Structurale (IPBS), Université de Toulouse, CNRS, Université Toulouse III - Paul Sabatier (UT3), Toulouse, France
| | - Arnaud Labrousse
- Institut de Pharmacologie et de Biologie Structurale (IPBS), Université de Toulouse, CNRS, Université Toulouse III - Paul Sabatier (UT3), Toulouse, France
| | - Jean-Philippe Girard
- Institut de Pharmacologie et de Biologie Structurale (IPBS), Université de Toulouse, CNRS, Université Toulouse III - Paul Sabatier (UT3), Toulouse, France
- Equipe Labellisée Ligue Contre le Cancer, Paris, France
| | - Isabelle Maridonneau-Parini
- Institut de Pharmacologie et de Biologie Structurale (IPBS), Université de Toulouse, CNRS, Université Toulouse III - Paul Sabatier (UT3), Toulouse, France
| | - Christel Vérollet
- Institut de Pharmacologie et de Biologie Structurale (IPBS), Université de Toulouse, CNRS, Université Toulouse III - Paul Sabatier (UT3), Toulouse, France
| | - Frédéric Lagarrigue
- Institut de Pharmacologie et de Biologie Structurale (IPBS), Université de Toulouse, CNRS, Université Toulouse III - Paul Sabatier (UT3), Toulouse, France
| | - Alba Diz-Muñoz
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Julien Heuvingh
- PMMH, ESPCI Paris, PSL University, CNRS, Université Paris Cité, Sorbonne Université, Paris, France
| | - Matthieu Piel
- Institut Curie and Institut Pierre Gilles de Gennes, PSL University, CNRS, Paris, France
| | - Olivia du Roure
- PMMH, ESPCI Paris, PSL University, CNRS, Université Paris Cité, Sorbonne Université, Paris, France
| | - Véronique Le Cabec
- Institut de Pharmacologie et de Biologie Structurale (IPBS), Université de Toulouse, CNRS, Université Toulouse III - Paul Sabatier (UT3), Toulouse, France.
| | - Sébastien Carréno
- Institut de Recherche en Immunologie et en Cancérologie (IRIC), Université de Montréal, Montréal, Canada.
| | - Renaud Poincloux
- Institut de Pharmacologie et de Biologie Structurale (IPBS), Université de Toulouse, CNRS, Université Toulouse III - Paul Sabatier (UT3), Toulouse, France.
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3
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Hausrat TJ, Vogl C, Neef J, Schweizer M, Yee BK, Strenzke N, Kneussel M. Monoallelic loss of the F-actin-binding protein radixin facilitates startle reactivity and pre-pulse inhibition in mice. Front Cell Dev Biol 2022; 10:987691. [DOI: 10.3389/fcell.2022.987691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Accepted: 11/11/2022] [Indexed: 11/29/2022] Open
Abstract
Hearing impairment is one of the most common disorders with a global burden and increasing prevalence in an ever-aging population. Previous research has largely focused on peripheral sensory perception, while the brain circuits of auditory processing and integration remain poorly understood. Mutations in the rdx gene, encoding the F-actin binding protein radixin (Rdx), can induce hearing loss in human patients and homozygous depletion of Rdx causes deafness in mice. However, the precise physiological function of Rdx in hearing and auditory information processing is still ill-defined. Here, we investigated consequences of rdx monoallelic loss in the mouse. Unlike the homozygous (−/−) rdx knockout, which is characterized by the degeneration of actin-based stereocilia and subsequent hearing loss, our analysis of heterozygous (+/−) mutants has revealed a different phenotype. Specifically, monoallelic loss of rdx potentiated the startle reflex in response to acoustic stimulation of increasing intensities, suggesting a gain of function relative to wildtype littermates. The monoallelic loss of the rdx gene also facilitated pre-pulse inhibition of the acoustic startle reflex induced by weak auditory pre-pulse stimuli, indicating a modification to the circuit underlying sensorimotor gating of auditory input. However, the auditory brainstem response (ABR)-based hearing thresholds revealed a mild impairment in peripheral sound perception in rdx (+/-) mice, suggesting minor aberration of stereocilia structural integrity. Taken together, our data suggest a critical role of Rdx in the top-down processing and/or integration of auditory signals, and therefore a novel perspective to uncover further Rdx-mediated mechanisms in central auditory information processing.
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4
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Schacke S, Kirkpatrick J, Stocksdale A, Bauer R, Hagel C, Riecken LB, Morrison H. Ezrin deficiency triggers glial fibrillary acidic protein upregulation and a distinct reactive astrocyte phenotype. Glia 2022; 70:2309-2329. [PMID: 35929192 DOI: 10.1002/glia.24253] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Revised: 07/12/2022] [Accepted: 07/15/2022] [Indexed: 01/02/2023]
Abstract
Astrocytes are increasingly being recognized as contributors to physiological brain function and behavior. Astrocytes engage in glia-synaptic interactions through peripheral astrocyte processes, thus modulating synaptic signaling, for example, by handling glutamate removal from the synaptic cleft and (re)provision to axonal terminals. Peripheral astrocyte processes are ultrafine membrane protrusions rich in the membrane-to-actin cytoskeleton linker Ezrin, an essential component of in vitro filopodia formation and in vivo peripheral astrocyte process motility. Consequently, it has been postulated that Ezrin significantly contributes to neurodevelopment as well as astrocyte functions within the adult brain. However, while Ezrin has been studied in vitro within cultured primary astrocytes, in vivo studies on the role of Ezrin in astrocytes remain to be conducted and consequences of its depletion to be studied. Here, we investigated consequences of Ezrin deletion in the mouse brain starting from early neuronal specification. While Ezrin knockout did not impact prenatal cerebral cortex development, behavioral phenotyping depicted reduced exploratory behavior. Starting with postnatal appearance of glia cells, Ezrin was verified to remain predominantly expressed in astrocytes. Proteome analysis of Ezrin deficient astrocytes revealed alterations in glutamate and ion homeostasis, metabolism and cell morphology - important processes for synaptic signal transmission. Notably, Ezrin deletion in astrocytes provoked (GFAP) glial fibrillary acidic protein upregulation - a marker of astrocyte activation and reactive astrogliosis. However, this spontaneous, reactive astrogliosis exhibited proteome changes distinct from ischemic-induced reactive astrogliosis. Moreover, in experimental ischemic stroke, Ezrin knockout mice displayed reduced infarct volume, indicating a protective effect of the Ezrin deletion-induced changes and astrogliosis.
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Affiliation(s)
- Stephan Schacke
- Leibniz Institute on Aging, Fritz Lipmann Institute, Jena, Germany
| | | | - Amy Stocksdale
- Leibniz Institute on Aging, Fritz Lipmann Institute, Jena, Germany
| | - Reinhard Bauer
- Institute of Molecular Cell Biology, CMB, Jena University Hospital, Jena, Germany
| | - Christian Hagel
- Institute of Neuropathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | | | - Helen Morrison
- Leibniz Institute on Aging, Fritz Lipmann Institute, Jena, Germany.,Faculty of Biological Sciences, Friedrich-Schiller University, Jena, Germany
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5
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Cai WT, Kim WY, Kwak MJ, Rim H, Lee SE, Riecken LB, Morrison H, Kim J. Disruption of amphetamine sensitization by alteration of dendritic thin spines in the nucleus accumbens core. J Neurochem 2022; 161:266-280. [DOI: 10.1111/jnc.15582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 01/17/2022] [Accepted: 01/20/2022] [Indexed: 11/28/2022]
Affiliation(s)
- Wen Ting Cai
- Department of Physiology Yonsei University College of Medicine Seoul Republic of Korea
| | - Wha Young Kim
- Department of Physiology Yonsei University College of Medicine Seoul Republic of Korea
| | - Myung Ji Kwak
- Department of Medical Sciences Yonsei University College of Medicine Seoul Republic of Korea
| | - Haeun Rim
- Department of Medical Sciences Yonsei University College of Medicine Seoul Republic of Korea
| | - Seung Eun Lee
- Virus Facility, Research Animal Source Center Korea Institute of Science and Technology Seoul Republic of Korea
| | | | - Helen Morrison
- Leibniz Institute on Aging Fritz Lipmann Institute Jena Germany
| | - Jeong‐Hoon Kim
- Department of Physiology Yonsei University College of Medicine Seoul Republic of Korea
- Department of Medical Sciences Yonsei University College of Medicine Seoul Republic of Korea
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6
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MMP-9 Signaling Pathways That Engage Rho GTPases in Brain Plasticity. Cells 2021; 10:cells10010166. [PMID: 33467671 PMCID: PMC7830260 DOI: 10.3390/cells10010166] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 01/12/2021] [Accepted: 01/12/2021] [Indexed: 02/08/2023] Open
Abstract
The extracellular matrix (ECM) has been identified as a critical factor affecting synaptic function. It forms a functional scaffold that provides both the structural support and the reservoir of signaling molecules necessary for communication between cellular constituents of the central nervous system (CNS). Among numerous ECM components and modifiers that play a role in the physiological and pathological synaptic plasticity, matrix metalloproteinase 9 (MMP-9) has recently emerged as a key molecule. MMP-9 may contribute to the dynamic remodeling of structural and functional plasticity by cleaving ECM components and cell adhesion molecules. Notably, MMP-9 signaling was shown to be indispensable for long-term memory formation that requires synaptic remodeling. The core regulators of the dynamic reorganization of the actin cytoskeleton and cell adhesion are the Rho family of GTPases. These proteins have been implicated in the control of a wide range of cellular processes occurring in brain physiology and pathology. Here, we discuss the contribution of Rho GTPases to MMP-9-dependent signaling pathways in the brain. We also describe how the regulation of Rho GTPases by post-translational modifications (PTMs) can influence these processes.
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7
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Hwang H, Hur YN, Sohn H, Seo J, Hong JH, Cho E, Choi Y, Lee S, Song S, Lee AR, Kim S, Jo DG, Rhim H, Park M. Cyclin Y, a novel actin-binding protein, regulates spine plasticity through the cofilin-actin pathway. Prog Neurobiol 2020; 198:101915. [PMID: 32966834 DOI: 10.1016/j.pneurobio.2020.101915] [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: 03/02/2020] [Revised: 09/05/2020] [Accepted: 09/15/2020] [Indexed: 11/16/2022]
Abstract
While positive regulators of hippocampal long-term potentiation (LTP) have extensively been investigated, relatively little is known about the inhibitory regulators of LTP. We previously reported that Cyclin Y (CCNY), a member of cyclin family generally known to function in proliferating cells, is a novel postsynaptic protein that serves as a negative regulator of functional LTP. However, whether CCNY plays a role in structural LTP, which is mechanistically linked to functional LTP, and which mechanisms are involved in the CCNY-mediated suppression of LTP at the molecular level remain elusive. Here, we report that CCNY negatively regulates the plasticity-induced changes in spine morphology through the control of actin dynamics. We observed that CCNY directly binds to filamentous actin and interferes with LTP-induced actin polymerization as well as depolymerization by blocking the activation of cofilin, an actin-depolymerizing factor, thus resulting in less plastic spines and the impairment of structural LTP. These data suggest that CCNY acts as an inhibitory regulator for both structural and functional LTP by modulating actin dynamics through the cofilin-actin pathway. Collectively, our findings provide a mechanistic insight into the inhibitory modulation of hippocampal LTP by CCNY, highlighting a novel function of a cyclin family protein in non-proliferating neuronal cells.
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Affiliation(s)
- Hongik Hwang
- Center for Functional Connectomics, Brain Science Institute, Korea Institute of Science and Technology, Seoul 02792, South Korea; Center for Neuroscience, Brain Science Institute, Korea Institute of Science and Technology, Seoul 02792, South Korea; School of Pharmacy, Sungkyunkwan University, Suwon 16419, South Korea
| | - Young-Na Hur
- Center for Functional Connectomics, Brain Science Institute, Korea Institute of Science and Technology, Seoul 02792, South Korea
| | - Heesung Sohn
- Center for Functional Connectomics, Brain Science Institute, Korea Institute of Science and Technology, Seoul 02792, South Korea; Department of Life Sciences, School of Natural Science, Hanyang University, Seoul 04763, South Korea
| | - Jiyeon Seo
- Center for Functional Connectomics, Brain Science Institute, Korea Institute of Science and Technology, Seoul 02792, South Korea; Center for Neuroscience, Brain Science Institute, Korea Institute of Science and Technology, Seoul 02792, South Korea
| | - Jung-Hwa Hong
- Center for Functional Connectomics, Brain Science Institute, Korea Institute of Science and Technology, Seoul 02792, South Korea; Department of Life Sciences, Korea University, Seoul 02841, South Korea
| | - Eunsil Cho
- Center for Functional Connectomics, Brain Science Institute, Korea Institute of Science and Technology, Seoul 02792, South Korea
| | - Yuri Choi
- Center for Functional Connectomics, Brain Science Institute, Korea Institute of Science and Technology, Seoul 02792, South Korea
| | - Saebom Lee
- Center for Functional Connectomics, Brain Science Institute, Korea Institute of Science and Technology, Seoul 02792, South Korea
| | - Seongeun Song
- Center for Functional Connectomics, Brain Science Institute, Korea Institute of Science and Technology, Seoul 02792, South Korea
| | - A-Ram Lee
- Center for Functional Connectomics, Brain Science Institute, Korea Institute of Science and Technology, Seoul 02792, South Korea
| | - Suyeon Kim
- Center for Functional Connectomics, Brain Science Institute, Korea Institute of Science and Technology, Seoul 02792, South Korea
| | - Dong-Gyu Jo
- School of Pharmacy, Sungkyunkwan University, Suwon 16419, South Korea
| | - Hyewhon Rhim
- Center for Neuroscience, Brain Science Institute, Korea Institute of Science and Technology, Seoul 02792, South Korea; Department of Neuroscience, Korea University of Science and Technology, Daejeon 34113, South Korea
| | - Mikyoung Park
- Center for Functional Connectomics, Brain Science Institute, Korea Institute of Science and Technology, Seoul 02792, South Korea; Department of Neuroscience, Korea University of Science and Technology, Daejeon 34113, South Korea.
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8
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ICAM5 as a Novel Target for Treating Cognitive Impairment in Fragile X Syndrome. J Neurosci 2019; 40:1355-1365. [PMID: 31882402 PMCID: PMC7002157 DOI: 10.1523/jneurosci.2626-18.2019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Revised: 12/12/2019] [Accepted: 12/15/2019] [Indexed: 12/11/2022] Open
Abstract
Fragile X syndrome (FXS) is the most common inherited form of intellectual disability, resulted from the silencing of the Fmr1 gene and the subsequent loss of fragile X mental retardation protein (FMRP). Spine dysgenesis and cognitive impairment have been extensively characterized in FXS; however, the underlying mechanism remains poorly understood. Fragile X syndrome (FXS) is the most common inherited form of intellectual disability, resulted from the silencing of the Fmr1 gene and the subsequent loss of fragile X mental retardation protein (FMRP). Spine dysgenesis and cognitive impairment have been extensively characterized in FXS; however, the underlying mechanism remains poorly understood. As an important regulator of spine maturation, intercellular adhesion molecule 5 (ICAM5) mRNA may be one of the targets of FMRP and involved in cognitive impairment in FXS. Here we show that in Fmr1 KO male mice, ICAM5 was excessively expressed during the late developmental stage, and its expression was negatively correlated with the expression of FMRP and positively related with the morphological abnormalities of dendritic spines. While in vitro reduction of ICAM5 normalized dendritic spine abnormalities in Fmr1 KO neurons, and in vivo knockdown of ICAM5 in the dentate gyrus rescued the impaired spatial and fear memory and anxiety-like behaviors in Fmr1 KO mice, through both granule cell and mossy cell with a relative rate of 1.32 ± 0.15. Furthermore, biochemical analyses showed direct binding of FMRP with ICAM5 mRNA, to the coding sequence of ICAM5 mRNA. Together, our study suggests that ICAM5 is one of the targets of FMRP and is implicated in the molecular pathogenesis of FXS. ICAM5 could be a therapeutic target for treating cognitive impairment in FXS. SIGNIFICANCE STATEMENT Fragile X syndrome (FXS) is characterized by dendritic spine dysgenesis and cognitive dysfunctions, while one of the FMRP latent targets, ICAM5, is well established for contributing both spine maturation and learning performance. In this study, we examined the potential link between ICAM5 mRNA and FMRP in FXS, and further investigated the molecular details and pathological consequences of ICAM5 overexpression. Our results indicate a critical role of ICAM5 in spine maturation and cognitive impairment in FXS and suggest that ICAM5 is a potential molecular target for the development of medication against FXS.
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Nakahata Y, Yasuda R. Plasticity of Spine Structure: Local Signaling, Translation and Cytoskeletal Reorganization. Front Synaptic Neurosci 2018; 10:29. [PMID: 30210329 PMCID: PMC6123351 DOI: 10.3389/fnsyn.2018.00029] [Citation(s) in RCA: 133] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 08/07/2018] [Indexed: 12/31/2022] Open
Abstract
Dendritic spines are small protrusive structures on dendritic surfaces, and function as postsynaptic compartments for excitatory synapses. Plasticity of spine structure is associated with many forms of long-term neuronal plasticity, learning and memory. Inside these small dendritic compartments, biochemical states and protein-protein interactions are dynamically modulated by synaptic activity, leading to the regulation of protein synthesis and reorganization of cytoskeletal architecture. This in turn causes plasticity of structure and function of the spine. Technical advances in monitoring molecular behaviors in single dendritic spines have revealed that each signaling pathway is differently regulated across multiple spatiotemporal domains. The spatial pattern of signaling activity expands from a single spine to the nearby dendritic area, dendritic branch and the nucleus, regulating different cellular events at each spatial scale. Temporally, biochemical events are typically triggered by short Ca2+ pulses (~10–100 ms). However, these signals can then trigger activation of downstream protein cascades that can last from milliseconds to hours. Recent imaging studies provide many insights into the biochemical processes governing signaling events of molecular assemblies at different spatial localizations. Here, we highlight recent findings of signaling dynamics during synaptic plasticity and discuss their roles in long-term structural plasticity of dendritic spines.
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Affiliation(s)
- Yoshihisa Nakahata
- Neuronal Signal Transduction, Max Planck Florida Institute for Neuroscience (MPFI), Jupiter, FL, United States
| | - Ryohei Yasuda
- Neuronal Signal Transduction, Max Planck Florida Institute for Neuroscience (MPFI), Jupiter, FL, United States
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10
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Furutani Y, Yoshihara Y. Proteomic Analysis of Dendritic Filopodia-Rich Fraction Isolated by Telencephalin and Vitronectin Interaction. Front Synaptic Neurosci 2018; 10:27. [PMID: 30147651 PMCID: PMC6097459 DOI: 10.3389/fnsyn.2018.00027] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Accepted: 07/19/2018] [Indexed: 01/13/2023] Open
Abstract
Dendritic filopodia are thin, long, and highly mobile protrusions functioning as spine precursors. By contrast with a wealth of knowledge on molecular profiles in spines, little is known about structural and functional proteins present in dendritic filopodia. To reveal the molecular constituents of dendritic filopodia, we developed a new method for biochemical preparation of proteins enriched in dendritic filopodia, by taking advantage of specific and strong binding between a dendritic filopodial membrane protein, telencephalin, and its extracellular matrix ligand, vitronectin. When vitronectin-coated magnetic microbeads were added onto cultured hippocampal neurons, phagocytic cup-like membrane protrusions were formed on dendrites through the binding to telencephalin. Magnetically purified membrane protrusion fraction was subjected to comprehensive mass spectrometric analysis and 319 proteins were identified, many of which were confirmed to be localized to dendritic filopodia. Thus, this study provides a useful resource for studying molecular mechanisms underlying dendritic development, synapse formation, and plasticity.
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Affiliation(s)
- Yutaka Furutani
- Laboratory for Neurobiology of Synapse, RIKEN Brain Science Institute, Saitama, Japan
| | - Yoshihiro Yoshihara
- Laboratory for Neurobiology of Synapse, RIKEN Brain Science Institute, Saitama, Japan.,Laboratory for Systems Molecular Ethology, RIKEN Center for Brain Science, Saitama, Japan
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11
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Merino P, Diaz A, Manrique LG, Cheng L, Yepes M. Urokinase-type plasminogen activator (uPA) promotes ezrin-mediated reorganization of the synaptic cytoskeleton in the ischemic brain. J Biol Chem 2018; 293:9234-9247. [PMID: 29720403 DOI: 10.1074/jbc.ra118.002534] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Revised: 03/30/2018] [Indexed: 11/06/2022] Open
Abstract
Synaptic repair in the ischemic brain is a complex process that requires reorganization of the actin cytoskeleton. Ezrin, radixin, and moesin (ERM) are a group of evolutionarily conserved proteins that link the plasma membrane to the actin cytoskeleton and act as scaffolds for signaling transduction. Urokinase-type plasminogen activator (uPA) is a serine proteinase that upon binding to the urokinase-type plasminogen activator receptor (uPAR) catalyzes the conversion of plasminogen into plasmin on the cell surface and activates intracellular signaling pathways. Early studies indicate that uPA and uPAR expression increase during the recovery phase from an ischemic stroke and that uPA binding to uPAR promotes neurorepair in the ischemic brain. The in vitro and in vivo studies presented here show that either the release of neuronal uPA or treatment with recombinant uPA induces the local synthesis of ezrin in the synapse and the recruitment of β3-integrin to the postsynaptic density (PSD) of cerebral cortical neurons by a plasminogen-independent mechanism. We found that β3-integrin has a double effect on ezrin, inducing its recruitment to the PSD via the intercellular adhesion molecule-5 (ICAM-5) and its subsequent activation by phosphorylation at Thr-567. Finally, our data indicate that by triggering the reorganization of the actin cytoskeleton in the postsynaptic terminal, active ezrin induces the recovery of dendritic spines and synapses that have been damaged by an acute ischemic stroke. In summary, our data show that uPA-uPAR binding promotes synaptic repair in the ischemic brain via ezrin-mediated reorganization of the actin cytoskeleton in the postsynaptic terminal.
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Affiliation(s)
- Paola Merino
- From the Division of Neuropharmacology and Neurologic Diseases, Yerkes National Primate Research Center, Atlanta, Georgia 30329.,the Department of Neurology and Center for Neurodegenerative Disease, Emory University School of Medicine, Atlanta, Georgia 30322, and
| | - Ariel Diaz
- From the Division of Neuropharmacology and Neurologic Diseases, Yerkes National Primate Research Center, Atlanta, Georgia 30329.,the Department of Neurology and Center for Neurodegenerative Disease, Emory University School of Medicine, Atlanta, Georgia 30322, and
| | - Luis Guillermo Manrique
- From the Division of Neuropharmacology and Neurologic Diseases, Yerkes National Primate Research Center, Atlanta, Georgia 30329.,the Department of Neurology and Center for Neurodegenerative Disease, Emory University School of Medicine, Atlanta, Georgia 30322, and
| | - Lihong Cheng
- From the Division of Neuropharmacology and Neurologic Diseases, Yerkes National Primate Research Center, Atlanta, Georgia 30329.,the Department of Neurology and Center for Neurodegenerative Disease, Emory University School of Medicine, Atlanta, Georgia 30322, and
| | - Manuel Yepes
- From the Division of Neuropharmacology and Neurologic Diseases, Yerkes National Primate Research Center, Atlanta, Georgia 30329, .,the Department of Neurology and Center for Neurodegenerative Disease, Emory University School of Medicine, Atlanta, Georgia 30322, and.,the Department of Neurology, Veterans Affairs Medical Center, Atlanta, Georgia 30033
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12
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DeWitt JJ, Grepo N, Wilkinson B, Evgrafov OV, Knowles JA, Campbell DB. Impact of the Autism-Associated Long Noncoding RNA MSNP1AS on Neuronal Architecture and Gene Expression in Human Neural Progenitor Cells. Genes (Basel) 2016; 7:genes7100076. [PMID: 27690106 PMCID: PMC5083915 DOI: 10.3390/genes7100076] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Revised: 09/08/2016] [Accepted: 09/23/2016] [Indexed: 01/26/2023] Open
Abstract
We previously identified the long noncoding RNA (lncRNA) MSNP1AS (moesin pseudogene 1, antisense) as a functional element revealed by genome wide significant association with autism spectrum disorder (ASD). MSNP1AS expression was increased in the postmortem cerebral cortex of individuals with ASD and particularly in individuals with the ASD-associated genetic markers on chromosome 5p14.1. Here, we mimicked the overexpression of MSNP1AS observed in postmortem ASD cerebral cortex in human neural progenitor cell lines to determine the impact on neurite complexity and gene expression. ReNcell CX and SK-N-SH were transfected with an overexpression vector containing full-length MSNP1AS. Neuronal complexity was determined by the number and length of neuronal processes. Gene expression was determined by strand-specific RNA sequencing. MSNP1AS overexpression decreased neurite number and neurite length in both human neural progenitor cell lines. RNA sequencing revealed changes in gene expression in proteins involved in two biological processes: protein synthesis and chromatin remodeling. These data indicate that overexpression of the ASD-associated lncRNA MSNP1AS alters the number and length of neuronal processes. The mechanisms by which MSNP1AS overexpression impacts neuronal differentiation may involve protein synthesis and chromatin structure. These same biological processes are also implicated by rare mutations associated with ASD, suggesting convergent mechanisms.
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Affiliation(s)
- Jessica J DeWitt
- Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA.
| | - Nicole Grepo
- Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA.
| | - Brent Wilkinson
- Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA.
| | - Oleg V Evgrafov
- Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA.
- Department of Psychiatry and the Behavioral Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA.
| | - James A Knowles
- Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA.
- Department of Psychiatry and the Behavioral Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA.
| | - Daniel B Campbell
- Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA.
- Department of Psychiatry and the Behavioral Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA.
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13
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Miyamoto A, Wake H, Ishikawa AW, Eto K, Shibata K, Murakoshi H, Koizumi S, Moorhouse AJ, Yoshimura Y, Nabekura J. Microglia contact induces synapse formation in developing somatosensory cortex. Nat Commun 2016; 7:12540. [PMID: 27558646 PMCID: PMC5007295 DOI: 10.1038/ncomms12540] [Citation(s) in RCA: 432] [Impact Index Per Article: 54.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2015] [Accepted: 07/12/2016] [Indexed: 01/17/2023] Open
Abstract
Microglia are the immune cells of the central nervous system that play important roles in brain pathologies. Microglia also help shape neuronal circuits during development, via phagocytosing weak synapses and regulating neurogenesis. Using in vivo multiphoton imaging of layer 2/3 pyramidal neurons in the developing somatosensory cortex, we demonstrate here that microglial contact with dendrites directly induces filopodia formation. This filopodia formation occurs only around postnatal day 8-10, a period of intense synaptogenesis and when microglia have an activated phenotype. Filopodia formation is preceded by contact-induced Ca(2+) transients and actin accumulation. Inhibition of microglia by genetic ablation decreases subsequent spine density, functional excitatory synapses and reduces the relative connectivity from layer 4 neurons. Our data provide the direct demonstration of microglial-induced spine formation and provide further insights into immune system regulation of neuronal circuit development, with potential implications for developmental disorders of immune and brain dysfunction.
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Affiliation(s)
- Akiko Miyamoto
- Division of Homeostatic Development, National Institute for Physiological Sciences, Okazaki 444-8585, Japan
- Core Research for Evolutional Science and Technology, Japan Agency for Medical Research and Development, Tokyo 100-0004, Japan
| | - Hiroaki Wake
- Division of Homeostatic Development, National Institute for Physiological Sciences, Okazaki 444-8585, Japan
- Core Research for Evolutional Science and Technology, Japan Agency for Medical Research and Development, Tokyo 100-0004, Japan
- Department of Physiological Sciences, The Graduate School for Advanced Study, Hayama 240-0193, Japan
- Precursory Research for Embryonic Science and Technology, Japan Science and Technology Agency, Saitama 102-0076, Japan
| | - Ayako Wendy Ishikawa
- Department of Physiological Sciences, The Graduate School for Advanced Study, Hayama 240-0193, Japan
- Division of Visual Information Processing, National Institute for Physiological Sciences, Okazaki 444-8585, Japan
| | - Kei Eto
- Division of Homeostatic Development, National Institute for Physiological Sciences, Okazaki 444-8585, Japan
- Core Research for Evolutional Science and Technology, Japan Agency for Medical Research and Development, Tokyo 100-0004, Japan
- Department of Physiological Sciences, The Graduate School for Advanced Study, Hayama 240-0193, Japan
| | - Keisuke Shibata
- Core Research for Evolutional Science and Technology, Japan Agency for Medical Research and Development, Tokyo 100-0004, Japan
- Department of Pharmacology, Graduated School of Medical and Engineering, Yamanashi University, Chuo 409-3898, Japan
| | - Hideji Murakoshi
- Precursory Research for Embryonic Science and Technology, Japan Science and Technology Agency, Saitama 102-0076, Japan
- Section of Multiphoton Neuroimaging, National Institute for Physiological Sciences, Okazaki 444-8585, Japan
| | - Schuichi Koizumi
- Core Research for Evolutional Science and Technology, Japan Agency for Medical Research and Development, Tokyo 100-0004, Japan
- Department of Pharmacology, Graduated School of Medical and Engineering, Yamanashi University, Chuo 409-3898, Japan
| | - Andrew J. Moorhouse
- School of Medical Sciences, The University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Yumiko Yoshimura
- Department of Physiological Sciences, The Graduate School for Advanced Study, Hayama 240-0193, Japan
- Division of Visual Information Processing, National Institute for Physiological Sciences, Okazaki 444-8585, Japan
| | - Junichi Nabekura
- Division of Homeostatic Development, National Institute for Physiological Sciences, Okazaki 444-8585, Japan
- Core Research for Evolutional Science and Technology, Japan Agency for Medical Research and Development, Tokyo 100-0004, Japan
- Department of Physiological Sciences, The Graduate School for Advanced Study, Hayama 240-0193, Japan
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14
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Brain enhancer activities at the gene-poor 5p14.1 autism-associated locus. Sci Rep 2016; 6:31227. [PMID: 27503586 PMCID: PMC4977510 DOI: 10.1038/srep31227] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Accepted: 07/14/2016] [Indexed: 12/19/2022] Open
Abstract
Due to the vast clinical and genetic heterogeneity, identification of causal genetic determinants for autism spectrum disorder (ASD) has proven to be complex. Whereas several dozen ‘rare’ genetic variants for ASD susceptibility have been identified, studies are still underpowered to analyse ‘common’ variants for their subtle effects. A recent application of genome-wide association studies (GWAS) to ASD indicated significant associations with the single nucleotide polymorphisms (SNPs) on chromosome 5p14.1, located in a non-coding region between cadherin10 (CDH10) and cadherin9 (CDH9). Here we apply an in vivo bacterial artificial chromosome (BAC) based enhancer-trapping strategy in mice to scan the gene desert for spatiotemporal cis-regulatory activities. Our results show that the ASD-associated interval harbors the cortical area, striatum, and cerebellum specific enhancers for a long non-coding RNA, moesin pseudogene1 antisense (MSNP1AS) during the brain developing stages. Mouse moesin protein levels are not affected by exogenously expressed human antisense RNAs in our transgenic brains, demonstrating the difficulty in modeling rather smaller effects of common variants. Our first in vivo evidence for the spatiotemporal transcription of MSNP1AS however provides a further support to connect this intergenic variant with the ASD susceptibility.
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15
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Eckstrum KS, Weis KE, Baur NG, Yoshihara Y, Raetzman LT. Icam5 Expression Exhibits Sex Differences in the Neonatal Pituitary and Is Regulated by Estradiol and Bisphenol A. Endocrinology 2016; 157:1408-20. [PMID: 26789235 PMCID: PMC4816737 DOI: 10.1210/en.2015-1521] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Endocrine-disrupting chemicals are prevalent in the environment and can impair reproductive success by affecting the hypothalamic-pituitary-gonadal axis. The developing pituitary gland is sensitive to exposure to endocrine-disrupting chemicals, such as bisphenol A (BPA), and sex-specific effects can occur. However, effects on the critical window of neonatal pituitary gland development in mice have not been explored. Therefore, this study determined baseline gene expression in male and female pituitaries and consequences of environmental exposure to 17β-estradiol (E2) and BPA on transcription of genes exhibiting sex differences during the neonatal period. Through microarray and quantitative RT-PCR analysis of pituitaries at postnatal day (PND)1, 3 genes were differentially expressed between males and females: Lhb, Fshb, and intracellular adhesion molecule-5 (Icam5). To see whether E2 and BPA exposure regulates these genes, pituitaries were cultured at PND1 with 10(-8) M E2 or 4.4 × 10(-6) M BPA. E2 decreased expression of Lhb, Fshb, and Icam5 mRNA in females but only significantly decreased expression of Icam5 in males. BPA decreased expression of Icam5 similarly to E2, but it did not affect Lhb or Fshb. Importantly, in vivo exposure to 50-μg/kg · d E2 from PND0 to PND7 decreased expression of Lhb, Fshb, and Icam5 mRNA in both males and females, whereas 50-mg/kg · d BPA exposure during the same time frame decreased expression of Icam5 in females only. Overall, we have uncovered that genes differentially expressed between the sexes can be regulated in part by hormonal and chemical signals in vivo and directly at the pituitary and can be regulated in a sex-specific manner.
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Affiliation(s)
- Kirsten S Eckstrum
- Department of Molecular and Integrative Physiology (K.S.E., K.E.W., N.G.B., L.T.R.), University of Illinois at Urbana-Champaign, Urbana, Illinois 61801; and RIKEN Brain Science Institute (Y.Y.), Wako, Saitama 351-0198, Japan
| | - Karen E Weis
- Department of Molecular and Integrative Physiology (K.S.E., K.E.W., N.G.B., L.T.R.), University of Illinois at Urbana-Champaign, Urbana, Illinois 61801; and RIKEN Brain Science Institute (Y.Y.), Wako, Saitama 351-0198, Japan
| | - Nicholas G Baur
- Department of Molecular and Integrative Physiology (K.S.E., K.E.W., N.G.B., L.T.R.), University of Illinois at Urbana-Champaign, Urbana, Illinois 61801; and RIKEN Brain Science Institute (Y.Y.), Wako, Saitama 351-0198, Japan
| | - Yoshihiro Yoshihara
- Department of Molecular and Integrative Physiology (K.S.E., K.E.W., N.G.B., L.T.R.), University of Illinois at Urbana-Champaign, Urbana, Illinois 61801; and RIKEN Brain Science Institute (Y.Y.), Wako, Saitama 351-0198, Japan
| | - Lori T Raetzman
- Department of Molecular and Integrative Physiology (K.S.E., K.E.W., N.G.B., L.T.R.), University of Illinois at Urbana-Champaign, Urbana, Illinois 61801; and RIKEN Brain Science Institute (Y.Y.), Wako, Saitama 351-0198, Japan
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16
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Mechanisms of Long Non-coding RNAs in Mammalian Nervous System Development, Plasticity, Disease, and Evolution. Neuron 2015; 88:861-877. [DOI: 10.1016/j.neuron.2015.09.045] [Citation(s) in RCA: 303] [Impact Index Per Article: 33.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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17
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Ning L, Paetau S, Nyman-Huttunen H, Tian L, Gahmberg CG. ICAM-5 affects spine maturation by regulation of NMDA receptor binding to α-actinin. Biol Open 2015; 4:125-36. [PMID: 25572420 PMCID: PMC4365481 DOI: 10.1242/bio.201410439] [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] [Indexed: 11/23/2022] Open
Abstract
ICAM-5 is a negative regulator of dendritic spine maturation and facilitates the formation of filopodia. Its absence results in improved memory functions, but the mechanisms have remained poorly understood. Activation of NMDA receptors induces ICAM-5 ectodomain cleavage through a matrix metalloproteinase (MMP)-dependent pathway, which promotes spine maturation and synapse formation. Here, we report a novel, ICAM-5-dependent mechanism underlying spine maturation by regulating the dynamics and synaptic distribution of α-actinin. We found that GluN1 and ICAM-5 partially compete for the binding to α-actinin; deletion of the cytoplasmic tail of ICAM-5 or ablation of the gene resulted in increased association of GluN1 with α-actinin, whereas internalization of ICAM-5 peptide perturbed the GluN1/α-actinin interaction. NMDA treatment decreased α-actinin binding to ICAM-5, and increased the binding to GluN1. Proper synaptic distribution of α-actinin requires the ICAM-5 cytoplasmic domain, without which α-actinin tended to accumulate in filopodia, leading to F-actin reorganization. The results indicate that ICAM-5 retards spine maturation by preventing reorganization of the actin cytoskeleton, but NMDA receptor activation is sufficient to relieve the brake and promote the maturation of spines.
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Affiliation(s)
- Lin Ning
- Division of Biochemistry and Biotechnology, Faculty of Biological and Environmental Sciences, University of Helsinki, Viikinkaari 5, FIN-00014, Helsinki, Finland
| | - Sonja Paetau
- Division of Biochemistry and Biotechnology, Faculty of Biological and Environmental Sciences, University of Helsinki, Viikinkaari 5, FIN-00014, Helsinki, Finland
| | - Henrietta Nyman-Huttunen
- Division of Biochemistry and Biotechnology, Faculty of Biological and Environmental Sciences, University of Helsinki, Viikinkaari 5, FIN-00014, Helsinki, Finland
| | - Li Tian
- Neuroscience Center, University of Helsinki, Viikinkaari 4, FIN-00014, Helsinki, Finland
| | - Carl G Gahmberg
- Division of Biochemistry and Biotechnology, Faculty of Biological and Environmental Sciences, University of Helsinki, Viikinkaari 5, FIN-00014, Helsinki, Finland
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18
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Kelly EA, Tremblay ME, Gahmberg CG, Tian L, Majewska AK. Subcellular localization of intercellular adhesion molecule-5 (telencephalin) in the visual cortex is not developmentally regulated in the absence of matrix metalloproteinase-9. J Comp Neurol 2014; 522:676-88. [PMID: 23897576 DOI: 10.1002/cne.23440] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2012] [Revised: 07/11/2012] [Accepted: 07/18/2013] [Indexed: 02/06/2023]
Abstract
The telencephalon-associated intercellular adhesion molecule-5 (telencephalin; ICAM-5) regulates dendritic morphology in the developing brain. In vitro studies have shown that ICAM-5 is found predominantly within dendrites and immature dendritic protrusions, with reduced expression in mushroom spines, suggesting that ICAM-5 downregulation is critical for the maturation of synaptic structures. However, developmental expression of ICAM-5 has not been explored in depth at the ultrastructural level in intact brain tissue. To investigate the ultrastructural localization of ICAM-5 with transmission electron microscopy, we performed immunoperoxidase histochemistry for ICAM-5 in mouse visual cortex at postnatal day (P)14, a period of intense synaptogenesis, and at P28, when synapses mature. We observed the expected ICAM-5 expression in dendritic protrusions and shafts at both P14 and P28. ICAM-5 expression in these dendritic protrusions decreased in prevalence with developmental age to become localized predominantly to dendritic shafts by P28. To understand better the relationship between ICAM-5 and the endopeptidase metalloproteinase-9 (MMP-9), which mediates ICAM-5 cleavage following glutamate activation during postnatal development, we also explored ICAM-5 expression in MMP-9 null animals. This analysis revealed a similar expression of ICAM-5 in dendritic elements at P14 and P28; however, an increased prevalence of ICAM-5 was noted in dendritic protrusions at P28 in the MMP-9 null animals, indicating that, in the absence of MMP-9, there is no developmental shift in ICAM-5 subcellular localization. Our ultrastructural observations shed light on possible functions mediated by ICAM-5 and their regulation by extracellular proteases.
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Affiliation(s)
- Emily A Kelly
- Department of Neurobiology and Anatomy, University of Rochester, Rochester, New York, 14642
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19
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Mao J, Zhang M, Zhong M, Zhang Y, Lv K. MicroRNA-204, a direct negative regulator of ezrin gene expression, inhibits glioma cell migration and invasion. Mol Cell Biochem 2014; 396:117-28. [PMID: 25055875 DOI: 10.1007/s11010-014-2148-6] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2014] [Accepted: 07/11/2014] [Indexed: 12/14/2022]
Abstract
Ezrin is overexpressed in a variety of neoplastic cells and involved in the later stages of tumor progression and metastasis. Ezrin expression can be regulated at both the transcriptional and post-transcriptional levels. We used a combination of bioinformatics and experimental techniques to demonstrate that the miR-204 is a direct negative regulator of ezrin. Overexpression of miR-204 mimics decreased the activity of a luciferase reporter containing the ezrin 3' UTR and led to repression of ezrin protein. In contrast, ectopic expression of miR-204 inhibitor elevated ezrin expression. We also show that miR-204 is down-regulated in a panel of glioma tissues and in high invasive glioma cell lines we examined. Moreover, miR-204 mimics significantly reduced glioma cell migration and invasion, while miR-204 inhibitor generated the opposite results. Finally, overexpression of miR-204 and knockdown of ezrin reduced glioma cell invasion, and these effects could be rescued by re-expression of ezrin. These findings reveal that miR-204 could be partly due to its inhibitory effects on glioma cell migration and invasion through regulating ezrin expression.
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Affiliation(s)
- Jie Mao
- Department of Neurosurgery of The first affiliated Hospital, Wannan Medical College, 2 West Zheshan Road, Wuhu, 241001, Anhui, People's Republic of China
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20
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Recacha R, Jiménez D, Tian L, Barredo R, Gahmberg CG, Casasnovas JM. Crystal structures of an ICAM-5 ectodomain fragment show electrostatic-based homophilic adhesions. ACTA CRYSTALLOGRAPHICA. SECTION D, BIOLOGICAL CRYSTALLOGRAPHY 2014; 70:1934-43. [PMID: 25004970 PMCID: PMC4089487 DOI: 10.1107/s1399004714009468] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Accepted: 04/27/2014] [Indexed: 11/16/2022]
Abstract
Intercellular cell adhesion molecule-5 (ICAM-5) is a member of the ICAM subfamily that is exclusively expressed in the telencephalon region of the brain. The crystal structure of the four most N-terminal glycosylated domains (D1-D4) of ICAM-5 was determined in three different space groups and the D1-D5 fragment was modelled. The structures showed a curved molecule with two pronounced interdomain bends between D2 and D3 and between D3 and D4, as well as some interdomain flexibility. In contrast to ICAM-1, ICAM-5 has patches of positive and negative electrostatic charge at D1-D2 and at D3-D5, respectively. ICAM-5 can mediate homotypic interactions. In the crystals, several charge-based intermolecular interactions between the N-terminal and C-terminal moieties of the ICAM-5 molecules were observed, which defined an interacting surface in the D1-D4 fragment. One of the crystal lattices has a molecular assembly that could represent the homophilic ICAM-5 cell adhesion complex in neurons.
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Affiliation(s)
- Rosario Recacha
- Centro Nacional de Biotecnología (CNB–CSIC), Campus Universidad Autónoma de Madrid, Darwin 3,, 28049 Madrid, Spain
| | - David Jiménez
- Centro Nacional de Biotecnología (CNB–CSIC), Campus Universidad Autónoma de Madrid, Darwin 3,, 28049 Madrid, Spain
| | - Li Tian
- Neuroscience Center, University of Helsinki, 00014 Helsinki, Finland
| | - Román Barredo
- Centro Nacional de Biotecnología (CNB–CSIC), Campus Universidad Autónoma de Madrid, Darwin 3,, 28049 Madrid, Spain
| | - Carl G. Gahmberg
- Division of Biochemistry and Biotechnology, University of Helsinki, 00014 Helsinki, Finland
| | - José M. Casasnovas
- Centro Nacional de Biotecnología (CNB–CSIC), Campus Universidad Autónoma de Madrid, Darwin 3,, 28049 Madrid, Spain
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21
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Liao XM, Yang XD, Jia J, Li JT, Xie XM, Su YA, Schmidt MV, Si TM, Wang XD. Blockade of corticotropin-releasing hormone receptor 1 attenuates early-life stress-induced synaptic abnormalities in the neonatal hippocampus. Hippocampus 2014; 24:528-40. [DOI: 10.1002/hipo.22254] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2013] [Revised: 01/05/2014] [Accepted: 01/24/2014] [Indexed: 11/11/2022]
Affiliation(s)
- Xue-Mei Liao
- Institute of Mental Health; Peking University; 100191 Beijing China
- Key Laboratory for Mental Health, Ministry of Health (Peking University); 100191 Beijing China
| | - Xiao-Dun Yang
- Institute of Mental Health; Peking University; 100191 Beijing China
- Key Laboratory for Mental Health, Ministry of Health (Peking University); 100191 Beijing China
| | - Jiao Jia
- Institute of Mental Health; Peking University; 100191 Beijing China
- Key Laboratory for Mental Health, Ministry of Health (Peking University); 100191 Beijing China
- Department of Mental Health; Dayi Hospital Affiliated to Shanxi Medical University; 030032 Taiyuan China
| | - Ji-Tao Li
- Institute of Mental Health; Peking University; 100191 Beijing China
- Key Laboratory for Mental Health, Ministry of Health (Peking University); 100191 Beijing China
| | - Xiao-Meng Xie
- Institute of Mental Health; Peking University; 100191 Beijing China
- Key Laboratory for Mental Health, Ministry of Health (Peking University); 100191 Beijing China
| | - Yun-Ai Su
- Institute of Mental Health; Peking University; 100191 Beijing China
- Key Laboratory for Mental Health, Ministry of Health (Peking University); 100191 Beijing China
| | - Mathias V. Schmidt
- Max Planck Institute of Psychiatry, RG Neurobiology of Stress; 80804 Munich Germany
| | - Tian-Mei Si
- Institute of Mental Health; Peking University; 100191 Beijing China
- Key Laboratory for Mental Health, Ministry of Health (Peking University); 100191 Beijing China
| | - Xiao-Dong Wang
- Institute of Mental Health; Peking University; 100191 Beijing China
- Key Laboratory for Mental Health, Ministry of Health (Peking University); 100191 Beijing China
- Department of Neurobiology; Key Laboratory of Medical Neurobiology of Ministry of Health of China; Zhejiang Province Key Laboratory of Neurobiology; Zhejiang University School of Medicine; 310058 Hangzhou China
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22
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Gahmberg CG, Ning L, Paetau S. ICAM-5: a neuronal dendritic adhesion molecule involved in immune and neuronal functions. ADVANCES IN NEUROBIOLOGY 2014; 8:117-32. [PMID: 25300135 DOI: 10.1007/978-1-4614-8090-7_6] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
The neuron-specific intercellular adhesion molecule-5 (ICAM-5, telencephalin) is a member of the ICAM family of adhesion proteins. It has a complex structure with nine external immunoglobulin domains followed by a transmembrane and a cytoplasmic domain. The external part binds to beta1- and beta2-integrins and the matrix protein vitronectin, whereas its transmembrane domain binds to presenilins and the cytoplasmic domain to alpha-actinin and the ERM family of cytoplasmic proteins. In neurons it is confined to the soma and dendrites and it is enriched in dendritic filopodia with less expression in more mature dendritic spines. ICAM-5 strongly stimulates neurite outgrowth. ICAM-5 is cleaved by matrix metalloproteases upon activation of glutamate receptors or degraded through endocytosis resulting in increased spine maturation. Ablation of ICAM-5 expression increases functional synapse formation. The cleaved soluble fragment of ICAM-5 is immunosuppressive, which may be important in neuronal inflammatory diseases.
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23
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Kelly EA, Tremblay MÈ, Gahmberg CG, Tian L, Majewska AK. Interactions between intercellular adhesion molecule-5 positive elements and their surroundings in the rodent visual cortex. Commun Integr Biol 2013; 6:e27315. [PMID: 24753788 PMCID: PMC3984291 DOI: 10.4161/cib.27315] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2013] [Revised: 11/21/2013] [Accepted: 11/22/2013] [Indexed: 11/19/2022] Open
Abstract
The telencephalon-associated intercellular adhesion molecule 5 (Telencephalin; ICAM-5) regulates dendritic maturation, a process dependent on extracellular proteases in the developing brain. Using transmission electron microscopy, we have reported previously that ICAM-5 is localized primarily in dendritic protrusions during a period of robust synaptogenesis (P14 in mouse visual cortex). As dendritic protrusions mature (P28), ICAM-5 immuno-reactivity shifts from dendritic protrusions into dendritic shafts. ICAM-5 immuno-reactivity does not shift in animals lacking the matrix metalloproteinase-9 (MMP-9), a protease shown to regulate ICAM-5 cleavage. Cleaved ICAM-5 (soluble fraction; sICAM-5) has been shown to bind to a number of receptors located in neighboring structures, resulting in a variety of downstream signaling events, including enhanced neurotransmission. Here, we investigated the potential MMP-regulated ICAM-5 signaling by examining the relationship between ICAM-5 immuno-positive elements and the structures that directly neighbor them.
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Affiliation(s)
- Emily A Kelly
- Neurobiology & Anatomy; University of Rochester; Rochester, NY USA
| | | | - Carl G Gahmberg
- Department of Bioscience; University of Helsinki; Helsinki, Finland
| | - Li Tian
- Neuroscience Center; University of Helsinki; Helsinki, Finland
| | - Ania K Majewska
- Neurobiology & Anatomy; University of Rochester; Rochester, NY USA
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Lonskaya I, Partridge J, Lalchandani RR, Chung A, Lee T, Vicini S, Hoe HS, Lim ST, Conant K. Soluble ICAM-5, a product of activity dependent proteolysis, increases mEPSC frequency and dendritic expression of GluA1. PLoS One 2013; 8:e69136. [PMID: 23844251 PMCID: PMC3699500 DOI: 10.1371/journal.pone.0069136] [Citation(s) in RCA: 35] [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: 03/19/2013] [Accepted: 06/12/2013] [Indexed: 11/23/2022] Open
Abstract
Matrix metalloproteinases (MMPs) are zinc dependent endopeptidases that can be released from neurons in an activity dependent manner to play a role in varied forms of learning and memory. MMP inhibitors impair hippocampal long term potentiation (LTP), spatial memory, and behavioral correlates of drug addiction. Since MMPs are thought to influence LTP through a β1 integrin dependent mechanism, it has been suggested that these enzymes cleave specific substrates to generate integrin binding ligands. In previously published work, we have shown that neuronal activity stimulates rapid MMP dependent shedding of intercellular adhesion molecule-5 (ICAM-5), a synaptic adhesion molecule expressed on dendrites of the telencephalon. We have also shown that the ICAM-5 ectodomain can interact with β1 integrins to stimulate integrin dependent phosphorylation of cofilin, an event that occurs with dendritic spine maturation and LTP. In the current study, we investigate the potential for the ICAM-5 ectodomain to stimulate changes in α-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate receptor (AMPAR) dependent glutamatergic transmission. Single cell recordings show that the ICAM-5 ectodomain stimulates an increase in the frequency, but not the amplitude, of AMPA mini excitatory post synaptic currents (mEPSCs). With biotinylation and precipitation assays, we also show that the ICAM-5 ectodomain stimulates an increase in membrane levels of GluA1, but not GluA2, AMPAR subunits. In addition, we observe an ICAM-5 associated increase in GluA1 phosphorylation at serine 845. Concomitantly, ICAM-5 affects an increase in GluA1 surface staining along dendrites without affecting an increase in dendritic spine number. Together these data are consistent with the possibility that soluble ICAM-5 increases glutamatergic transmission and that post-synaptic changes, including increased phosphorylation and dendritic insertion of GluA1, could contribute. We suggest that future studies are warranted to determine whether ICAM-5 is one of a select group of synaptic CAMs whose shedding contributes to MMP dependent effects on learning and memory.
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Affiliation(s)
- Irina Lonskaya
- Department of Neuroscience, Georgetown University Medical Center, Washington, D.C., United States of America
| | - John Partridge
- Department of Pharmacology and Physiology, Georgetown University Medical Center, Washington, D.C., United States of America
- Interdisciplinary Program in Neuroscience, Georgetown University Medical Center, Washington, D.C., United States of America
| | - Rupa R. Lalchandani
- Interdisciplinary Program in Neuroscience, Georgetown University Medical Center, Washington, D.C., United States of America
| | - Andrew Chung
- Department of Neuroscience, Georgetown University Medical Center, Washington, D.C., United States of America
| | - Taehee Lee
- Department of Neuroscience, Georgetown University Medical Center, Washington, D.C., United States of America
| | - Stefano Vicini
- Department of Pharmacology and Physiology, Georgetown University Medical Center, Washington, D.C., United States of America
- Interdisciplinary Program in Neuroscience, Georgetown University Medical Center, Washington, D.C., United States of America
| | - Hyang-Sook Hoe
- Department of Neuroscience, Georgetown University Medical Center, Washington, D.C., United States of America
- Interdisciplinary Program in Neuroscience, Georgetown University Medical Center, Washington, D.C., United States of America
| | - Seung T. Lim
- Department of Neuroscience, Georgetown University Medical Center, Washington, D.C., United States of America
- Interdisciplinary Program in Neuroscience, Georgetown University Medical Center, Washington, D.C., United States of America
| | - Katherine Conant
- Department of Neuroscience, Georgetown University Medical Center, Washington, D.C., United States of America
- Interdisciplinary Program in Neuroscience, Georgetown University Medical Center, Washington, D.C., United States of America
- * E-mail:
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Kvalvaag AS, Pust S, Sundet KI, Engedal N, Simm R, Sandvig K. The ERM proteins ezrin and moesin regulate retrograde Shiga toxin transport. Traffic 2013; 14:839-52. [PMID: 23593995 DOI: 10.1111/tra.12077] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2012] [Revised: 04/12/2013] [Accepted: 04/17/2013] [Indexed: 01/23/2023]
Abstract
The ERM proteins (ezrin, radixin and moesin) are known for connecting the actin cytoskeleton to the plasma membrane. They have been found to associate with lipid rafts as well as to be important for endosomal sorting and receptor signaling. However, little is known about the role of ERM proteins in retrograde transport and lipid homeostasis. In this study, we show that ezrin and moesin are important for efficient cell surface association of Shiga toxin (Stx) as well as for its retrograde transport. Furthermore, we show that depletion of these proteins influences endosomal dynamics and seems to enhance Stx transport toward lysosomes. We also show that knockdown of Vps11, a subunit of the HOPS complex, leads to increased retrograde Stx transport and reverses the inhibiting effect of ezrin and moesin knockdown. Importantly, retrograde transport of the plant toxin ricin, which binds to both glycolipids and glycoproteins with a terminal galactose, seems to be unaffected by ezrin and moesin depletion.
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Affiliation(s)
- Audun Sverre Kvalvaag
- Department of Biochemistry, Institute for Cancer Research, The Norwegian Radium Hospital, Oslo University Hospital, Montebello, N-0379, Oslo, Norway
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Verslegers M, Lemmens K, Van Hove I, Moons L. Matrix metalloproteinase-2 and -9 as promising benefactors in development, plasticity and repair of the nervous system. Prog Neurobiol 2013; 105:60-78. [PMID: 23567503 DOI: 10.1016/j.pneurobio.2013.03.004] [Citation(s) in RCA: 310] [Impact Index Per Article: 28.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2012] [Revised: 03/01/2013] [Accepted: 03/28/2013] [Indexed: 11/16/2022]
Abstract
It has been 50 years since Gross and Lapiere discovered collagenolytic activity during tadpole tail metamorphosis, which was later on revealed as MMP-1, the founding member of the matrix metalloproteinases (MMPs). Currently, MMPs constitute a large group of endoproteases that are not only able to cleave all protein components of the extracellular matrix, but also to activate or inactivate many other signaling molecules, such as receptors, adhesion molecules and growth factors. Elevated MMP levels are associated with an increasing number of injuries and disorders, such as cancer, inflammation and auto-immune diseases. Yet, MMP upregulation has also been implicated in many physiological functions such as embryonic development, wound healing and angiogenesis and therefore, these proteinases are considered to be crucial mediators in many biological processes. Over the past decennia, MMP research has gained considerable attention in several pathologies, most prominently in the field of cancer metastasis, and more recent investigations also focus on the nervous system, with a striking emphasis on the gelatinases, MMP-2 and MMP-9. Unfortunately, the contribution of these gelatinases to neuropathological disorders, like multiple sclerosis and Alzheimer's disease, has overshadowed their potential as modulators of fundamental nervous system functions. Within this review, we wish to highlight the currently known or suggested actions of MMP-2 and MMP-9 in the developing and adult nervous system and their potential to improve repair or regeneration after nervous system injury.
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Affiliation(s)
- Mieke Verslegers
- Laboratory of Neural Circuit Development and Regeneration, Animal Physiology and Neurobiology Section, Department of Biology, KU Leuven, Leuven, Belgium
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27
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Mori Y, Matsui T, Fukuda M. Rabex-5 protein regulates dendritic localization of small GTPase Rab17 and neurite morphogenesis in hippocampal neurons. J Biol Chem 2013; 288:9835-9847. [PMID: 23430262 DOI: 10.1074/jbc.m112.427591] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Small GTPase Rab17 has recently been shown to regulate dendritic morphogenesis of mouse hippocampal neurons; however, the exact molecular mechanism of Rab17-mediated dendritogenesis remained to be determined, because no guanine nucleotide exchange factor (GEF) for Rab17 had been identified. In this study we screened for the Rab17-GEF by performing yeast two-hybrid assays with a GDP-locked Rab17 mutant as bait and found that Rabex-5 and ALS2, both of which were originally described as Rab5-GEFs, interact with Rab17. We also found that expression of Rabex-5, but not of ALS2, promotes translocation of Rab17 from the cell body to the dendrites of developing mouse hippocampal neurons. The shRNA-mediated knockdown of Rabex-5 or its known downstream target Rab5 in hippocampal neurons inhibited morphogenesis of both axons and dendrites, whereas knockdown of Rab17 affected dendrite morphogenesis alone. Based on these findings, we propose that Rabex-5 regulates neurite morphogenesis of hippocampal neurons by activating at least two downstream targets, Rab5, which is localized in both axons and dendrites, and Rab17, which is localized in dendrites alone.
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Affiliation(s)
- Yasunori Mori
- Laboratory of Membrane Trafficking Mechanisms, Department of Developmental Biology and Neurosciences, Graduate School of Life Sciences, Tohoku University, Aobayama, Aoba-ku, Sendai, Miyagi 980-8578, Japan
| | - Takahide Matsui
- Laboratory of Membrane Trafficking Mechanisms, Department of Developmental Biology and Neurosciences, Graduate School of Life Sciences, Tohoku University, Aobayama, Aoba-ku, Sendai, Miyagi 980-8578, Japan
| | - Mitsunori Fukuda
- Laboratory of Membrane Trafficking Mechanisms, Department of Developmental Biology and Neurosciences, Graduate School of Life Sciences, Tohoku University, Aobayama, Aoba-ku, Sendai, Miyagi 980-8578, Japan.
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28
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Kobayashi Y, Harada A, Furuta B, Asou H, Kato U, Umeda M. The role of NADRIN, a Rho GTPase-activating protein, in the morphological differentiation of astrocytes. J Biochem 2013; 153:389-98. [DOI: 10.1093/jb/mvt005] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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29
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Pollard JR, Eidelman O, Mueller GP, Dalgard CL, Crino PB, Anderson CT, Brand EJ, Burakgazi E, Ivaturi SK, Pollard HB. The TARC/sICAM5 Ratio in Patient Plasma is a Candidate Biomarker for Drug Resistant Epilepsy. Front Neurol 2013; 3:181. [PMID: 23293627 PMCID: PMC3535822 DOI: 10.3389/fneur.2012.00181] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2012] [Accepted: 12/09/2012] [Indexed: 12/14/2022] Open
Abstract
Epilepsy is a common affliction that involves inflammatory processes. There are currently no definitive chemical diagnostic biomarkers in the blood, so diagnosis is based on a sometimes expensive synthesis of clinical observation, radiology, neuro-psychological testing, and interictal and ictal EEG studies. Soluble ICAM5 (sICAM5), also known as telencephalin, is an anti-inflammatory protein of strictly central nervous system tissue origin that is also found in blood. Here we have tested the hypothesis that plasma concentrations of select inflammatory cytokines, including sICAM5, might serve as biomarkers for epilepsy diagnosis. To test this hypothesis, we developed a highly sensitive and accurate electrochemiluminescent ELISA assay to measure sICAM5 levels, and measured levels of sICAM5 and 18 other inflammatory mediators in epilepsy patient plasma and controls. Patient samples were drawn from in-patients undergoing video-EEG monitoring, without regard to timing of seizures. Differences were defined by t-test, and Receiver Operating Condition (ROC) curves determined the ability of these tests to distinguish between the two populations. In epilepsy patient plasmas, we found that concentrations of anti-inflammatory sICAM5 are reduced (p = 0.002) and pro-inflammatory IL-1β, IL-2, and IL-8 are elevated. TARC (thymus and activation regulated chemokine, CCL17) concentrations trend high. In contrast, levels of BDNF and a variety of other pro-inflammatory mediators are not altered. Based on p-value and ROC analysis, we find that the ratio of TARC/sICAM5 discriminates accurately between patients and controls, with an ROC Area Under the Curve (AUC) of 1.0 (p = 0.034). In conclusion, we find that the ratio of TARC to sICAM5 accurately distinguishes between the two populations and provides a statistically and mechanistically compelling candidate blood biomarker for drug resistant epilepsy.
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Affiliation(s)
- John R Pollard
- Penn Epilepsy Center, Department of Neurology, University of Pennsylvania Philadelphia, PA, USA
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30
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Xiao X, Mruk DD, Cheng CY. Intercellular adhesion molecules (ICAMs) and spermatogenesis. Hum Reprod Update 2013; 19:167-86. [PMID: 23287428 DOI: 10.1093/humupd/dms049] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND During the seminiferous epithelial cycle, restructuring takes places at the Sertoli-Sertoli and Sertoli-germ cell interface to accommodate spermatogonia/spermatogonial stem cell renewal via mitosis, cell cycle progression and meiosis, spermiogenesis and spermiation since developing germ cells, in particular spermatids, move 'up and down' the seminiferous epithelium. Furthermore, preleptotene spermatocytes differentiated from type B spermatogonia residing at the basal compartment must traverse the blood-testis barrier (BTB) to enter the adluminal compartment to prepare for meiosis at Stage VIII of the epithelial cycle, a process also accompanied by the release of sperm at spermiation. These cellular events that take place at the opposite ends of the epithelium are co-ordinated by a functional axis designated the apical ectoplasmic specialization (ES)-BTB-basement membrane. However, the regulatory molecules that co-ordinate cellular events in this axis are not known. METHODS Literature was searched at http://www.pubmed.org and http://scholar.google.com to identify published findings regarding intercellular adhesion molecules (ICAMs) and the regulation of this axis. RESULTS Members of the ICAM family, namely ICAM-1 and ICAM-2, and the biologically active soluble ICAM-1 (sICAM-1) are the likely regulatory molecules that co-ordinate these events. sICAM-1 and ICAM-1 have antagonistic effects on the Sertoli cell tight junction-permeability barrier, involved in Sertoli cell BTB restructuring, whereas ICAM-2 is restricted to the apical ES, regulating spermatid adhesion during the epithelial cycle. Studies in other epithelia/endothelia on the role of the ICAM family in regulating cell movement are discussed and this information has been evaluated and integrated into studies of these proteins in the testis to create a hypothetical model, depicting how ICAMs regulate junction restructuring events during spermatogenesis. CONCLUSIONS ICAMs are crucial regulatory molecules of spermatogenesis. The proposed hypothetical model serves as a framework in designing functional experiments for future studies.
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Affiliation(s)
- Xiang Xiao
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, 1230 York Avenue, New York, NY 10065, USA
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31
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Yang H, Wu D, Zhang X, Wang X, Peng Y, Hu Z. Telencephalin protects PAJU cells from amyloid beta protein-induced apoptosis by activating the ezrin/radixin/moesin protein family/phosphatidylinositol-3-kinase/protein kinase B pathway. Neural Regen Res 2012; 7:2189-98. [PMID: 25538739 PMCID: PMC4268718 DOI: 10.3969/j.issn.1673-5374.2012.028.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2012] [Accepted: 06/13/2012] [Indexed: 11/20/2022] Open
Abstract
Telencephalin is a neural glycoprotein that reduces apoptosis induced by amyloid beta protein in the human neural tumor cell line PAJU. In this study, we examined the role of the ezrin/radixin/moesin protein family/phosphatidylinositol-3-kinase/protein kinase B pathway in this process. Western blot analysis demonstrated that telencephalin, phosphorylated ezrin/radixin/moesin and phosphatidylinositol-3-kinase/protein kinase B were not expressed in PAJU cells transfected with empty plasmid, while they were expressed in PAJU cells transfected with a telencephalin expression plasmid. After treatment with 1.0 nM amyloid beta protein 42, expression of telencephalin and phosphorylated phosphatidylinositol-3-kinase/protein kinase B in the transfected cells gradually diminished, while levels of phosphorylated ezrin/radixin/moesin increased. In addition, the high levels of telencephalin, phosphorylated ezrin/radixin/moesin and phosphatidylinositol-3-kinase/protein kinase B expression in PAJU cells transfected with a telencephalin expression plasmid could be suppressed by the phosphatidylinositol-3-kinase inhibitor LY294002. These findings indicate that telencephalin activates the ezrin/radixin/moesin family/phosphatidylinositol-3-kinase/protein kinase B pathway and protects PAJU cells from amyloid beta protein-induced apoptosis.
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Affiliation(s)
- Heping Yang
- Department of Neurology, Shangrao No. 5 People's Hospital, the Second Affiliated Hospital of Nanchang University, Shangrao 334000, Jiangxi Province, China
- Department of Neurology, Ruikang Hospital Affiliated to Guangxi Traditional Chinese Medical University, Nanning 530011, Guangxi Zhuang Autonomous Region, China
- Department of Neurology, Xiangya Second Hospital, Central South University, Changsha 410011, Hunan Province, China
| | - Dapeng Wu
- Department of Neurology, Xiangya Second Hospital, Central South University, Changsha 410011, Hunan Province, China
| | - Xiaojie Zhang
- Department of Psychiatry, Xiangya Second Hospital, Central South University, Changsha 410011, Hunan Province, China
| | - Xiang Wang
- Department of Neurology, Xiangya Second Hospital, Central South University, Changsha 410011, Hunan Province, China
| | - Yi Peng
- Department of Neurology, Xiangya Second Hospital, Central South University, Changsha 410011, Hunan Province, China
| | - Zhiping Hu
- Department of Neurology, Xiangya Second Hospital, Central South University, Changsha 410011, Hunan Province, China
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32
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Furutani Y, Kawasaki M, Matsuno H, Mitsui S, Mori K, Yoshihara Y. Vitronectin induces phosphorylation of ezrin/radixin/moesin actin-binding proteins through binding to its novel neuronal receptor telencephalin. J Biol Chem 2012; 287:39041-9. [PMID: 23019340 DOI: 10.1074/jbc.m112.383851] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Vitronectin (VN) is an extracellular matrix protein abundantly present in blood and a wide variety of tissues and plays important roles in a number of biological phenomena mainly through its binding to αV integrins. However, its definite function in the brain remains largely unknown. Here we report the identification of telencephalin (TLCN/ICAM-5) as a novel VN receptor on neuronal dendrites. VN strongly binds to TLCN, a unique neuronal member of the ICAM family, which is specifically expressed on dendrites of spiny neurons in the mammalian telencephalon. VN-coated microbeads induce the formation of phagocytic cup-like plasma membrane protrusions on dendrites of cultured hippocampal neurons and trigger the activation of TLCN-dependent intracellular signaling cascade including the phosphorylation of ezrin/radixin/moesin actin-binding proteins and recruitment of F-actin and phosphatidylinositol 4,5-bisphosphate for morphological transformation of the dendritic protrusions. These results suggest that the extracellular matrix molecule VN and its neuronal receptor TLCN play a pivotal role in the phosphorylation of ezrin/radixin/moesin proteins and the formation of phagocytic cup-like structures on neuronal dendrites.
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Affiliation(s)
- Yutaka Furutani
- Laboratory for Neurobiology of Synapse, RIKEN Brain Science Institute, Saitama 351-0198, Japan
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33
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Niedringhaus M, Chen X, Dzakpasu R, Conant K. MMPs and soluble ICAM-5 increase neuronal excitability within in vitro networks of hippocampal neurons. PLoS One 2012; 7:e42631. [PMID: 22912716 PMCID: PMC3418258 DOI: 10.1371/journal.pone.0042631] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2012] [Accepted: 07/09/2012] [Indexed: 12/16/2022] Open
Abstract
Matrix metalloproteinases (MMPs) are zinc-dependent endopeptidases that are released from neurons in an activity dependent manner. Published studies suggest their activity is important to varied forms of learning and memory. At least one MMP can stimulate an increase in the size of dendritic spines, structures which represent the post synaptic component for a large number of glutamatergic synapses. This change may be associated with increased synaptic glutamate receptor incorporation, and an increased amplitude and/or frequency of α-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate (AMPA) mini excitatory post-synaptic currents (EPSCs). An associated increase in the probability of action potential occurrence would be expected. While the mechanism(s) by which MMPs may influence synaptic structure and function are not completely understood, MMP dependent shedding of specific cell adhesion molecules (CAMs) could play an important role. CAMs are ideally positioned to be cleaved by synaptically released MMPs, and shed N terminal domains could potentially interact with previously unengaged integrins to stimulate dendritic actin polymerization with spine expansion. In the present study, we have used multielectrode arrays (MEAs) to investigate MMP and soluble CAM dependent changes in neuronal activity recorded from hippocampal cultures. We have focused on intercellular adhesion molecule-5 (ICAM-5) in particular, as this CAM is expressed on glutamatergic dendrites and shed in an MMP dependent manner. We show that chemical long-term potentiation (cLTP) evoked changes in recorded activity, and the dynamics of action potential bursts in particular, are altered by MMP inhibition. A blocking antibody to β1 integrins has a similar effect. We also show that the ectodomain of ICAM-5 can stimulate β1 integrin dependent increases in spike counts and burst number. These results support a growing body of literature suggesting that MMPs have important effects on neuronal excitability. They also support the possibility that MMP dependent shedding of specific synaptic CAMs can contribute to these effects.
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Affiliation(s)
- Mark Niedringhaus
- Interdisciplinary Program in Neuroscience, Georgetown University Medical Center, Washington, District of Columbia, United States of America
| | - Xin Chen
- Department of Physics, Georgetown University, Washington, District of Columbia, United States of America
| | - Rhonda Dzakpasu
- Interdisciplinary Program in Neuroscience, Georgetown University Medical Center, Washington, District of Columbia, United States of America
- Department of Physics, Georgetown University, Washington, District of Columbia, United States of America
- Department of Pharmacology and Physiology, Georgetown University Medical Center, Washington, District of Columbia, United States of America
- * E-mail: (KC); (RD)
| | - Katherine Conant
- Interdisciplinary Program in Neuroscience, Georgetown University Medical Center, Washington, District of Columbia, United States of America
- Department of Neuroscience, Georgetown University Medical Center, Washington, District of Columbia, United States of America
- * E-mail: (KC); (RD)
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Kerin T, Ramanathan A, Rivas K, Grepo N, Coetzee GA, Campbell DB. A noncoding RNA antisense to moesin at 5p14.1 in autism. Sci Transl Med 2012; 4:128ra40. [PMID: 22491950 DOI: 10.1126/scitranslmed.3003479] [Citation(s) in RCA: 109] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
People with autism spectrum disorder (ASD) are characterized by deficits in social interaction, language, and behavioral flexibility. Rare mutations and copy number variations have been identified in individuals with ASD, but in most patients, the causal variants remain unknown. A genome-wide association study (GWAS), designed to identify genes and pathways that contribute to ASD, indicated a genome-wide significant association of ASD with the single-nucleotide polymorphism (SNP) rs4307059 (P = 10⁻¹⁰), which is located in a gene-poor region of chromosome 5p14.1. We describe here a 3.9-kb noncoding RNA that is transcribed from the region of the chromosome 5p14.1 ASD GWAS association SNP. The noncoding RNA was encoded by the opposite (antisense) strand of moesin pseudogene 1 (MSNP1), and we therefore designated it as MSNP1AS (moesin pseudogene 1, antisense). Chromosome 5p14.1 MSNP1AS was 94% identical and antisense to the X chromosome transcript of MSN, which encodes a protein (moesin) that regulates neuronal architecture. Individuals who carry the ASD-associated rs4307059 T allele showed increased expression of MSNP1AS. The MSNP1AS noncoding RNA bound to MSN, was highly overexpressed (12.7-fold) in postmortem cerebral cortex of individuals with ASD, and could regulate levels of moesin protein in human cell lines. These data reveal a biologically functional element that may contribute to ASD risk.
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Affiliation(s)
- Tara Kerin
- Program in Biomedical and Biological Sciences, University of Southern California, Los Angeles, CA 90089, USA
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35
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ARF6-mediated endosomal transport of Telencephalin affects dendritic filopodia-to-spine maturation. EMBO J 2012; 31:3252-69. [PMID: 22781129 PMCID: PMC3411082 DOI: 10.1038/emboj.2012.182] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2011] [Accepted: 06/11/2012] [Indexed: 01/21/2023] Open
Abstract
The GTPase Arf6 and its exchange factor EFA6A promote internalization of the Ig-like molecule Telencephalin in hippocampal neurons leading to the maturation of filopodia into dendritic spines, important for synapse formation. Dendritic filopodia are dynamic structures thought to be the precursors of spines during synapse development. Morphological maturation to spines is associated with the stabilization and strengthening of synapses, and can be altered in various neurological disorders. Telencephalin (TLN/intercellular adhesion molecule-5 (ICAM5)) localizes to dendritic filopodia, where it facilitates their formation/maintenance, thereby slowing spine morphogenesis. As spines are largely devoid of TLN, its exclusion from the filopodia surface appears to be required in this maturation process. Using HeLa cells and primary hippocampal neurons, we demonstrate that surface removal of TLN involves internalization events mediated by the small GTPase ADP-ribosylation factor 6 (ARF6), and its activator EFA6A. This endocytosis of TLN affects filopodia-to-spine transition, and requires Rac1-mediated dephosphorylation/release of actin-binding ERM proteins from TLN. At the somato-dendritic surface, TLN and EFA6A are confined to distinct, flotillin-positive membrane subdomains. The co-distribution of TLN with this lipid raft marker also persists during its endosomal targeting to CD63-positive late endosomes. This suggests a specific microenvironment facilitating ARF6-mediated mobilization of TLN that contributes to promotion of dendritic spine development.
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36
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Matsumoto Y, Murakami H, Hattori N, Yoshimoto K, Asano S, Inden M. Excessive expression of hippocampal ezrin is induced by intrastriatal injection of 6-hydroxydopamine. Biol Pharm Bull 2012; 34:1753-8. [PMID: 22040891 DOI: 10.1248/bpb.34.1753] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Accumulating evidence in humans demonstrates that visuo-spatial deficits are the most consistently reported cognitive abnormalities in Parkinson's disease (PD). Ezrin, radixin, and moesin are collectively known as ERM proteins. Although ERM proteins have important implications in cell-shape determination and relevant signaling pathway, they have not been studied in the hippocampus in association with visuo-spatial memory impairments. The purpose of the present study is to examine whether the expression level of ERM proteins in the hippocampus is changed by an intrastriatal injection of 6-hydroxydopamine (6-OHDA) in mice. The intrastriatal injection of 6-OHDA induced partial dopaminergic deficits and spatial memory impairments. We also found that ezrin was increased in the hippocampus by the microinjection of 6-OHDA. On the other hand, protein levels of radixin and moesin were not influenced by 6-OHDA lesions. These results suggest that excessive ezrin may be related to visuo-spatial memory impairments.
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Affiliation(s)
- Yosuke Matsumoto
- Department of Molecular Physiology, College of Pharmaceutical Sciences, Ritsumeikan University, Shiga, Japan
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37
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Sarto-Jackson I, Milenkovic I, Smalla KH, Gundelfinger ED, Kaehne T, Herrera-Molina R, Thomas S, Kiebler MA, Sieghart W. The cell adhesion molecule neuroplastin-65 is a novel interaction partner of γ-aminobutyric acid type A receptors. J Biol Chem 2012; 287:14201-14. [PMID: 22389504 DOI: 10.1074/jbc.m111.293175] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
γ-Aminobutyric acid type A (GABA(A)) receptors are pentameric ligand-gated ion channels that mediate fast inhibition in the central nervous system. Depending on their subunit composition, these receptors exhibit distinct pharmacological properties and differ in their ability to interact with proteins involved in receptor anchoring at synaptic or extra-synaptic sites. Whereas GABA(A) receptors containing α1, α2, or α3 subunits are mainly located synaptically where they interact with the submembranous scaffolding protein gephyrin, receptors containing α5 subunits are predominantly found extra-synaptically and seem to interact with radixin for anchorage. Neuroplastin is a cell adhesion molecule of the immunoglobulin superfamily that is involved in hippocampal synaptic plasticity. Our results reveal that neuroplastin and GABA(A) receptors can be co-purified from rat brain and exhibit a direct physical interaction as demonstrated by co-precipitation and Förster resonance energy transfer (FRET) analysis in a heterologous expression system. The brain-specific isoform neuroplastin-65 co-localizes with GABA(A) receptors as shown in brain sections as well as in neuronal cultures, and such complexes can either contain gephyrin or be devoid of gephyrin. Neuroplastin-65 specifically co-localizes with α1 or α2 but not with α3 subunits at GABAergic synapses. In addition, neuroplastin-65 also co-localizes with GABA(A) receptor α5 subunits at extra-synaptic sites. Down-regulation of neuroplastin-65 by shRNA causes a loss of GABA(A) receptor α2 subunits at GABAergic synapses. These results suggest that neuroplastin-65 can co-localize with a subset of GABA(A) receptor subtypes and might contribute to anchoring and/or confining GABA(A) receptors to particular synaptic or extra-synaptic sites, thus affecting receptor mobility and synaptic strength.
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Affiliation(s)
- Isabella Sarto-Jackson
- Center for Brain Research, Department of Biochemistry and Molecular Biology of the Nervous System, Medical University of Vienna, 1090 Vienna, Austria
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Kobayashi H, Fukuda M. Rab35 regulates Arf6 activity through centaurin-β2 (ACAP2) during neurite outgrowth. J Cell Sci 2012; 125:2235-43. [PMID: 22344257 DOI: 10.1242/jcs.098657] [Citation(s) in RCA: 109] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Two small GTPases, Rab and Arf, are well-known molecular switches that function in diverse membrane-trafficking routes in a coordinated manner; however, very little is known about the direct crosstalk between Rab and Arf. Although Rab35 and Arf6 were independently reported to regulate the same cellular events, including endocytic recycling, phagocytosis, cytokinesis and neurite outgrowth, the molecular basis that links them remains largely unknown. Here we show that centaurin-β2 (also known as ACAP2) functions both as a Rab35 effector and as an Arf6-GTPase-activating protein (GAP) during neurite outgrowth of PC12 cells. We found that Rab35 accumulates at Arf6-positive endosomes in response to nerve growth factor (NGF) stimulation and that centaurin-β2 is recruited to the same compartment in a Rab35-dependent manner. We further showed by knockdown and rescue experiments that after the Rab35-dependent recruitment of centaurin-β2, the Arf6-GAP activity of centaurin-β2 at the Arf6-positive endosomes was indispensable for NGF-induced neurite outgrowth. These findings suggest a novel mode of crosstalk between Rab and Arf: a Rab effector and Arf-GAP coupling mechanism, in which Arf-GAP is recruited to a specific membrane compartment by its Rab effector function.
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Affiliation(s)
- Hotaka Kobayashi
- Department of Developmental Biology and Neurosciences, Graduate School of Life Sciences, Tohoku University, Aoba-ku, Sendai, Miyagi, Japan
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Mori Y, Matsui T, Furutani Y, Yoshihara Y, Fukuda M. Small GTPase Rab17 regulates dendritic morphogenesis and postsynaptic development of hippocampal neurons. J Biol Chem 2012; 287:8963-73. [PMID: 22291024 DOI: 10.1074/jbc.m111.314385] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Neurons are compartmentalized into two morphologically, molecularly, and functionally distinct domains: axons and dendrites, and precise targeting and localization of proteins within these domains are critical for proper neuronal functions. It has been reported that several members of the Rab family small GTPases that are key mediators of membrane trafficking, regulate axon-specific trafficking events, but little has been elucidated regarding the molecular mechanisms that underlie dendrite-specific membrane trafficking. Here we show that Rab17 regulates dendritic morphogenesis and postsynaptic development in mouse hippocampal neurons. Rab17 is localized at dendritic growth cones, shafts, filopodia, and mature spines, but it is mostly absent in axons. We also found that Rab17 mediates dendrite growth and branching and that it does not regulate axon growth or branching. Moreover, shRNA-mediated knockdown of Rab17 expression resulted in a dramatically reduced number of dendritic spines, probably because of impaired filopodia formation. These findings have revealed the first molecular link between membrane trafficking and dendritogenesis.
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Affiliation(s)
- Yasunori Mori
- Laboratory of Membrane Trafficking Mechanisms, Department of Developmental Biology and Neurosciences, Graduate School of Life Sciences, Tohoku University, Aoba-ku, Sendai, Miyagi, Japan
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Structure, Expression, and Function of ICAM-5. Comp Funct Genomics 2012; 2012:368938. [PMID: 22312318 PMCID: PMC3270525 DOI: 10.1155/2012/368938] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2011] [Revised: 09/20/2011] [Accepted: 10/07/2011] [Indexed: 01/28/2023] Open
Abstract
Cell adhesion is of utmost importance in normal development and cellular functions. ICAM-5 (intercellular adhesion molecule-5, telencephalin, TLN) is a member of the ICAM family of adhesion proteins. As a novel cell adhesion molecule, ICAM-5 shares many structural similarities with the other members of IgSF, especially the ICAM subgroup; however, ICAM-5 has several unique properties compared to the other ICAMs. With its nine extracellular Ig domains, ICAM-5 is the largest member of ICAM subgroup identified so far. Therefore, it is much more complex than the other ICAMs. The expression of ICAM-5 is confined to the telencephalic neurons of the central nervous system whereas all the other ICAM members are expressed mostly by cells in the immune and blood systems. The developmental appearance of ICAM-5 parallels the time of dendritic elongation and branching, and synapse formation in the telencephalon. As a somatodendrite-specific adhesion molecule, ICAM-5 not only participates in immune-nervous system interactions, it could also participate in neuronal activity, Dendrites' targeting signals, and cognition. It would not be surprising if future investigations reveal more binding partners and other related functions of ICAM-5.
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Okabe S. Molecular Dynamics of the Excitatory Synapse. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012; 970:131-52. [DOI: 10.1007/978-3-7091-0932-8_6] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Urbanska M, Swiech L, Jaworski J. Developmental plasticity of the dendritic compartment: focus on the cytoskeleton. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012; 970:265-84. [PMID: 22351060 DOI: 10.1007/978-3-7091-0932-8_12] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Plasticity, the ability to undergo lasting changes in response to a stimulus, is an important attribute of neurons. It allows proper development and underlies learning, memory, and the recovery of the nervous system after severe injuries. Often, an outcome of neuronal plasticity is a structural plasticity manifested as a change of neuronal morphology. In this chapter, we focus on the structural plasticity of dendritic arbors and spines during development. Dendrites receive and compute synaptic inputs from other neurons. The number of dendrites and their branching pattern are strictly correlated with the function of a particular neuron and the geometry of the connections it receives. The development of proper dendritic tree morphology depends on the interplay between genetic programming and extracellular signals. Spines are tiny actin-rich dendritic protrusions that harbor excitatory synapses. No consensus has been reached regarding how dendritic spines form, and several models of spine morphogenesis exist. Nevertheless, most researchers agree that spinogenesis is an important target for structural plasticity. In this chapter, we discuss examples of such plasticity and describe the principles and molecular mechanisms underlying this process, focusing mostly on the regulation of the cytoskeleton during dendrito- and spinogenesis.
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Bukalo O, Dityatev A. Synaptic Cell Adhesion Molecules. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012; 970:97-128. [DOI: 10.1007/978-3-7091-0932-8_5] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Ohgomori T, Nanao T, Morita A, Ikekita M. Asn54-linked glycan is critical for functional folding of intercellular adhesion molecule-5. Glycoconj J 2011; 29:47-55. [PMID: 22187327 DOI: 10.1007/s10719-011-9363-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2011] [Revised: 11/21/2011] [Accepted: 11/28/2011] [Indexed: 11/24/2022]
Abstract
Intercellular adhesion molecule-5 (ICAM-5, telencephalin) is a dendritically polarized type I membrane glycoprotein, and promotes dendritic filopodia formation. Although we have determined the N-glycan structures of ICAM-5 in a previous report, their function is unknown. Here, we produced fifteen ICAM-5 gene constructs, in which each potential N-glycosylation site was mutated, to elucidate the function of the N-glycans of ICAM-5, and observed the effects of transfection of them on a neuronal cell line, Neuro-2a (N2a). Only the N54Q mutant, which is the mutant for the most N-terminal glycosylation site, failed to induce filopodia-like protrusions in N2a cells. Immunofluorescence staining and cell surface biotinylation revealed that N54Q ICAM-5 was confined to the ER and also could not be expressed on the cell surface. This is further supported by the biochemical evidence that almost all N-glycans of N54Q ICAM-5 were digested by Endo glycosidase H and peptide:N-glycanase, indicating that almost all of them retain high-mannose-type structures in ER. In additon, it also failed to form disulfide bonds or functional protein complexes. The stable transformants of N54Q ICAM-5 showed retarded cell growth, but it was interesting that there was no apparent ER stress, because the mutant was sequentially degraded via ER associated degradation pathway by comparing the susceptibilities of the responses to various inhibitors of this pathway in wild-type and N54Q ICAM-5 transfectants. Taken together, the Asn(54)-linked glycan is necessary for normal trafficking and function of ICAM-5, but is unassociated with ER-associated degradation of it.
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Affiliation(s)
- Tomohiro Ohgomori
- Department of Applied Biological Science, Faculty of Science and Technology, Tokyo University of Science, Yamazaki, Noda, Chiba, Japan.
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Jeong HJ, Kim JH, Jeon S. Amphetamine-induced ERM Proteins Phosphorylation Is through PKCβ Activation in PC12 Cells. THE KOREAN JOURNAL OF PHYSIOLOGY & PHARMACOLOGY : OFFICIAL JOURNAL OF THE KOREAN PHYSIOLOGICAL SOCIETY AND THE KOREAN SOCIETY OF PHARMACOLOGY 2011; 15:245-9. [PMID: 21994482 DOI: 10.4196/kjpp.2011.15.4.245] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2011] [Revised: 08/08/2011] [Accepted: 08/23/2011] [Indexed: 02/01/2023]
Abstract
Amphetamine, a synthetic psychostimulant, is transported by the dopamine transporter (DAT) to the cytosol and increases the exchange of extracellular amphetamine by intracellular dopamine. Recently, we reported that the phosphorylation levels of ezrin-radixin-moesin (ERM) proteins are regulated by psychostimulant drugs in the nucleus accumbens, a brain area important for drug addiction. However, the significance of ERM proteins phosphorylation in response to drugs of abuse has not been fully investigated. In this study, using PC12 cells as an in vitro cell model, we showed that amphetamine increases ERM proteins phosphorylation and protein kinase C (PKC) β inhibitor, but not extracellular signal-regulated kinase (ERK) or phosphatidylinositol 3-kinases (PI3K) inhibitors, abolished this effect. Further, we observed that DAT inhibitor suppressed amphetamine-induced ERM proteins phosphorylation in PC12 cells. These results suggest that PKCβ-induced DAT regulation may be involved in amphetmaine-induced ERM proteins phosphorylation.
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Affiliation(s)
- Ha Jin Jeong
- Dongguk University Research Institute of Biotechnology, Seoul 100-715, Korea
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Tang F, Zou F, Peng Z, Huang D, Wu Y, Chen Y, Duan C, Cao Y, Mei W, Tang X, Dong Z. N,N'-dinitrosopiperazine-mediated ezrin protein phosphorylation via activation of Rho kinase and protein kinase C is involved in metastasis of nasopharyngeal carcinoma 6-10B cells. J Biol Chem 2011; 286:36956-67. [PMID: 21878630 DOI: 10.1074/jbc.m111.259234] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
N,N'-Dinitrosopiperazine (DNP) is a carcinogen for nasopharyngeal carcinoma (NPC), which shows organ specificity to nasopharyngeal epithelium. Herein, we demonstrate that DNP induces fiber formation of NPC cells (6-10B) and also increases invasion and motility of 6-10B cells. DNP-mediated NPC metastasis also was confirmed in nude mice. Importantly, DNP induced the expression of phosphorylated ezrin (phos-ezrin) at threonine 567 (Thr-567) dose- and time-dependently but had no effect on the total ezrin expression at these concentrations. Furthermore, DNP-induced phos-ezrin expression was dependent on increased Rho kinase and protein kinase C (PKC) activity. DNP may activate Rho kinase through binding to its pleckstrin homology and may activate PKC through promoting its translocation to the plasma membrane in vivo. DNP-induced phos-ezrin was associated with induction of fiber growth in 6-10B cells. However, DNP could not induce motility and invasion of NPC cells containing ezrin mutated at Thr-567. Similarly, DNP could not induce motility and invasion of the cells containing siRNAs against Rho or PKC. These results indicate that DNP induces ezrin phosphorylation at Thr-567, increases motility and invasion of cells, and promotes tumor metastasis. DNP may be involved in NPC metastasis through regulation of ezrin phosphorylation at Thr-567.
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Affiliation(s)
- Faqing Tang
- Medical Research Center, Zhuhai Hospital, Guangzhou 510000, Guangdong, China.
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Abstract
AD (Alzheimer's disease) is a neurodegenerative disease characterized by a gradual loss of neurons and the accumulation of neurotoxic Aβ (amyloid β-peptide) and hyperphosphorylated tau. The discovery of mutations in three genes, PSEN1 (presenilin 1), PSEN2 (presenilin 2) and APP (amyloid precursor protein), in patients with FAD (familial AD) has made an important contribution towards an understanding of the disease aetiology; however, a complete molecular mechanism is still lacking. Both presenilins belong to the γ-secretase complex, and serve as the catalytic entity needed for the final cleavage of APP into Aβ. PSEN only functions within the γ-secretase complex through intra- and inter-molecular interactions with three other membrane components, including nicastrin, Aph-1 (anterior pharynx defective-1) and Pen-2 (PSEN enhancer-2). However, although the list of γ-secretase substrates is still expanding, other non-catalytic activities of presenilins are also increasing the complexity behind its molecular contribution towards AD. These γ-secretase-independent roles are so far mainly attributed to PSEN1, including the transport of membrane proteins, cell adhesion, ER (endoplasmic reticulum) Ca(2+) regulation and cell signalling. In the present minireview, we discuss the current understanding of the γ-secretase-independent roles of PSENs and their possible implications in respect of AD.
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Zhao R, Wang TZ, Kong D, Zhang L, Meng HX, Jiang Y, Wu YQ, Yu ZX, Jin XM. Hepatoma cell line HepG2.2.15 demonstrates distinct biological features compared with parental HepG2. World J Gastroenterol 2011; 17:1152-9. [PMID: 21448419 PMCID: PMC3063907 DOI: 10.3748/wjg.v17.i9.1152] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2010] [Revised: 11/29/2010] [Accepted: 12/06/2010] [Indexed: 02/06/2023] Open
Abstract
AIM: To investigate the biological features of hepatitis B virus (HBV)-transfected HepG2.2.15 cells.
METHODS: The cell ultrastructure, cell cycle and apoptosis, and the abilities of proliferation and invasion of HBV-transfected HepG2.2.15 and the parent HepG2 cells were examined by electron microscopy, flow cytometry, 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and trans-well assay. Oncogenicity of the two cell lines was compared via subcutaneous injection and orthotopic injection or implantation in nude mice, and the pathological analysis of tumor formation was performed. Two cytoskeletal proteins were detected by Western blotting.
RESULTS: Compared with HepG2 cells, HepG2.2.15 cells showed organelle degeneration and filopodia disappearance under electron microscope. HepG2.2.15 cells proliferated and migrated slowly in vitro, and hardly formed tumor and lung metastasis in nude mice. Flow cytometry showed that the majority of HepG2.2.15 cells were arrested in G1 phase, and apoptosis was minor in both cell lines. Furthermore, the levels of cytoskeletal proteins F-actin and Ezrin were decreased in HepG2.2.15 cells.
CONCLUSION: HepG2.2.15 cells demonstrated a lower proliferation and invasion ability than the HepG2 cells due to HBV transfection.
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Conant K, Lonskaya I, Szklarczyk A, Krall C, Steiner J, Maguire-Zeiss K, Lim ST. Methamphetamine-associated cleavage of the synaptic adhesion molecule intercellular adhesion molecule-5. J Neurochem 2011; 118:521-32. [PMID: 21166806 DOI: 10.1111/j.1471-4159.2010.07153.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Methamphetamine (MA) is a highly addictive psychostimulant that, used in excess, may be neurotoxic. Although the mechanisms that underlie its addictive potential are not completely understood, in animal models matrix metalloproteinase (MMP) inhibitors can reduce behavioral correlates of addiction. In addition, evidence from genome-wide association studies suggests that polymorphisms in synaptic cell-adhesion molecules (CAMs), known MMP substrates, are linked to addictive potential in humans. In the present study, we examined the ability of MA to stimulate cleavage of intercellular adhesion molecule-5 (ICAM-5), a synaptic CAM expressed on dendritic spines in the telencephalon. Previous studies have shown that shedding of ICAM-5 is associated with maturation of dendritic spines, and that MMP-dependent shedding occurs with long term potentiation. Herein, we show that MA stimulates ectodomain cleavage of ICAM-5 in vitro, and that this is abrogated by a broad spectrum MMP inhibitor. We also show that an acute dose of MA, administered in vivo, is associated with cleavage of ICAM-5 in murine hippocampus and striatum. This occurs within 6 h and is accompanied by an increase in MMP-9 protein. In related experiments, we examined the potential consequences of ICAM-5 shedding. We demonstrate that the ICAM-5 ectodomain can interact with β(1) integrins, and that it can stimulate β(1) integrin-dependent phosphorylation of cofilin, an event that has previously been linked to MMP-dependent spine maturation. Together these data support an emerging appreciation of MMPs as effectors of synaptic plasticity and suggest a mechanism by which MA may influence the same.
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Affiliation(s)
- Katherine Conant
- The Department of Neuroscience, Georgetown University Medical Center, Washington, District of Columbia 20007, USA.
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Chen N, Newcomb J, Garbuzova-Davis S, Sanberg CD, Sanberg PR, Willing AE. Human Umbilical Cord Blood Cells Have Trophic Effects on Young and Aging Hippocampal Neurons in Vitro. Aging Dis 2010; 1:173-190. [PMID: 21234285 PMCID: PMC3018847] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2010] [Revised: 10/15/2010] [Accepted: 10/20/2010] [Indexed: 05/30/2023] Open
Abstract
In experimental models of central nervous system (CNS) aging, injury and disease, administering human umbilical cord blood (HUCB) cells induce recovery, most likely by interacting with multiple cellular processes. The aim of this study was to examine whether the HUCB cells produce trophic factors that may enhance survival and maturation of hippocampal neurons in an in vitro test system. We co-cultured the mononuclear fraction of HUCB cells with hippocampal neurons isolated from either young (7-months of age) or aging (21 month of age) rat brain for 14, 21, 28, 35 and 42 days in vitro (DIV), respectively. Immunocytochemistry was then employed to identify neurons (MAP2(+)) and glial cells (GFAP(+)) as well as arborization of neurites. The average number of MAP2(+) hippocampal neurons cells in both young and aging neuronal-HUCB co-cultures was significantly higher than in the control cultures (hippocampal mono-cultures). These MAP2(+) neurons in co-culture were richly arborized, especially in 21 and 28 DIV co-cultures, and expressed functional enzymes (Synaptophysin, tyrosine hydryoxlase (TH)), gamma amino butyric acid receptor (GABAAr) and glutamate transporter (EAAC1). The majority of hippocampal neurons in both co-culture systems grew very well and survived for up to 42 DIV with an increment of immature neurons which were positive for Nestin and TuJ1. Using a multiplex protein array, a number of secreted proteins that could have trophic effects on the neurons were identified.
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Affiliation(s)
- Ning Chen
- Center of Excellence for Aging and Brain Repair
- Departments of Neurosurgery and Brain Repair
| | - Jennifer Newcomb
- Center of Excellence for Aging and Brain Repair
- Departments of Neurosurgery and Brain Repair
| | | | | | - Paul R. Sanberg
- Center of Excellence for Aging and Brain Repair
- Pathology and Cell Biology
- Saneron CCEL Therapeutics, Tampa, FL, USA
| | - Alison E. Willing
- Center of Excellence for Aging and Brain Repair
- Molecular Pharmacology and Physiology, University of South Florida College of Medicine, Tampa FL, USA
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