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Halmi CA, McIntosh AT, Leonard CE, Taneyhill LA. N-cadherin facilitates trigeminal sensory neuron outgrowth and target tissue innervation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.20.594965. [PMID: 38826314 PMCID: PMC11142107 DOI: 10.1101/2024.05.20.594965] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2024]
Abstract
During embryonic development, diverse cell types coordinate to form functionally complex tissues. Exemplifying this process, the trigeminal ganglion emerges from the condensation of two distinct precursor cell populations, cranial placodes and neural crest, with neuronal differentiation of the former preceding the latter. While the dual origin of the trigeminal ganglion has been understood for decades, the molecules orchestrating formation of the trigeminal ganglion from these precursors remain relatively obscure. Initial assembly of the trigeminal ganglion is mediated by cell adhesion molecules, including neural cadherin (N-cadherin), which is required by placodal neurons to properly condense with other neurons and neural crest cells. Whether N-cadherin is required for later growth and target innervation by trigeminal ganglion neurons, however, is unknown. To this end, we depleted N-cadherin from chick trigeminal placode cells and uncovered decreases in trigeminal ganglion size, nerve growth, and target innervation in vivo at later developmental stages. Furthermore, blocking N-cadherin-mediated adhesion prevented axon extension in some placode-derived trigeminal neurons in vitro . This indicates the existence of neuronal subtypes that may have unique requirements for N-cadherin for outgrowth, and points to this subset of placodal neurons as potential pioneers that serve as templates for additional axon outgrowth. Neurite complexity was also decreased in neural crest-derived neurons in vitro in response to N-cadherin knockdown in placode cells. Collectively, these findings reveal persistent cell autonomous and non-cell autonomous functions for N-cadherin, thus highlighting the critical role of N-cadherin in mediating reciprocal interactions between neural crest and placode neuronal derivatives during trigeminal ganglion development. Significance Statement Our findings are significant because they demonstrate how neurons derived from two distinct cell populations, neural crest and placode cells, coordinate the outgrowth of their axons in time and space to generate the trigeminal ganglion using the cell adhesion molecule N-cadherin. Notably, our results provide evidence for the existence of subpopulations of neurons within the trigeminal ganglion that differentially require N-cadherin to facilitate axon outgrowth, and hint at the possibility that trigeminal pioneer neurons are derived from placode cells while followers arise from both placode and neural crest cells. These studies provide new insight into trigeminal gangliogenesis that will likely be translatable to other cranial ganglia and vertebrate species.
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Tang Q, Ojiro R, Ozawa S, Zou X, Nakahara J, Nakao T, Koyanagi M, Jin M, Yoshida T, Shibutani M. DNA methylation-altered genes in the rat hippocampal neurogenic niche after continuous exposure to amorphous curcumin. J Chem Neuroanat 2024; 137:102414. [PMID: 38490283 DOI: 10.1016/j.jchemneu.2024.102414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2023] [Revised: 03/09/2024] [Accepted: 03/12/2024] [Indexed: 03/17/2024]
Abstract
Rat offspring who are exposed to an amorphous formula of curcumin (CUR) from the embryonic stage have anti-anxiety-like behaviors, enhanced fear extinction learning, and increased synaptic plasticity in the hippocampal dentate gyrus (DG). In the present study, we investigated the links between genes with altered methylation status in the neurogenic niche and enhanced neural functions after CUR exposure. We conducted methylation and RNA sequencing analyses of the DG of CUR-exposed rat offspring on day 77 after delivery. Methylation status and transcript levels of candidate genes were validated using methylation-sensitive high-resolution melting and real-time reverse-transcription PCR, respectively. In the CUR group, we confirmed the hypermethylation and downregulation of Gpr150, Mmp23, Rprml, and Pcdh8 as well as the hypomethylation and upregulation of Ppm1j, Fam222a, and Opn3. Immunohistochemically, reprimo-like+ hilar cells and protocadherin-8+ granule cells were decreased and opsin-3+ hilar cells were increased by CUR exposure. Both reprimo-like and opsin-3 were partially expressed on subpopulations of glutamic acid decarboxylase 67+ γ-aminobutyric acid-ergic interneurons. Furthermore, the transcript levels of genes involved in protocadherin-8-mediated N-cadherin endocytosis were altered with CUR exposure; this was accompanied by Ctnnb1 and Syp upregulation and Mapk14, Map2k3, and Grip1 downregulation, suggesting that CUR-induced enhanced synaptic plasticity is associated with cell adhesion. Together, our results indicate that functionally different genes have altered methylation and expression in different neuronal populations of the hippocampal neurogenic niche, thus enhancing synaptic plasticity after CUR exposure.
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Affiliation(s)
- Qian Tang
- Laboratory of Veterinary Pathology, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo 183-8509, Japan; Cooperative Division of Veterinary Sciences, Graduate School of Agriculture, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo 183-8509, Japan
| | - Ryota Ojiro
- Laboratory of Veterinary Pathology, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo 183-8509, Japan; Cooperative Division of Veterinary Sciences, Graduate School of Agriculture, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo 183-8509, Japan
| | - Shunsuke Ozawa
- Laboratory of Veterinary Pathology, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo 183-8509, Japan; Cooperative Division of Veterinary Sciences, Graduate School of Agriculture, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo 183-8509, Japan
| | - Xinyu Zou
- Laboratory of Veterinary Pathology, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo 183-8509, Japan; Cooperative Division of Veterinary Sciences, Graduate School of Agriculture, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo 183-8509, Japan
| | - Junta Nakahara
- Laboratory of Veterinary Pathology, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo 183-8509, Japan
| | - Tomohiro Nakao
- Emulsion Laboratory, San-Ei Gen F.F.I., Inc., 1-1-11 Sanwa-cho, Toyonaka-shi, Osaka 561-8588, Japan
| | - Mihoko Koyanagi
- Global Scientific and Regulatory Affairs, San-Ei Gen F.F.I., Inc., 1-1-11 Sanwa-cho, Toyonaka-shi, Osaka 561-8588, Japan
| | - Meilan Jin
- Laboratory of Veterinary Pathology, College of Veterinary Medicine, Southwest University, No. 2 Tiansheng Road, BeiBei District, Chongqing 400715, PR China
| | - Toshinori Yoshida
- Laboratory of Veterinary Pathology, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo 183-8509, Japan; Cooperative Division of Veterinary Sciences, Graduate School of Agriculture, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo 183-8509, Japan
| | - Makoto Shibutani
- Laboratory of Veterinary Pathology, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo 183-8509, Japan; Cooperative Division of Veterinary Sciences, Graduate School of Agriculture, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo 183-8509, Japan.
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Matcham AC, Toma K, Tsai NY, Sze CJ, Lin PY, Stewart IF, Duan X. Cadherin-13 Maintains Retinotectal Synapses via Transneuronal Interactions. J Neurosci 2024; 44:e1310232023. [PMID: 38123991 PMCID: PMC10860569 DOI: 10.1523/jneurosci.1310-23.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2023] [Revised: 12/03/2023] [Accepted: 12/05/2023] [Indexed: 12/23/2023] Open
Abstract
Maintaining precise synaptic contacts between neuronal partners is critical to ensure the proper functioning of the mammalian central nervous system (CNS). Diverse cell recognition molecules, such as classic cadherins (Cdhs), are part of the molecular machinery mediating synaptic choices during development and synaptic maintenance. Yet, the principles governing neuron-neuron wiring across diverse CNS neuron types remain largely unknown. The retinotectal synapses, connections from the retinal ganglion cells (RGCs) to the superior collicular (SC) neurons, offer an ideal experimental system to reveal molecular logic underlying synaptic choices and formation. This is due to the retina's unidirectional and laminar-restricted projections to the SC and the large databases of presynaptic RGC subtypes and postsynaptic SC neuronal types. Here, we focused on determining the role of Type II Cdhs in wiring the retinotectal synapses. We surveyed Cdhs expression patterns at neuronal resolution and revealed that Cdh13 is enriched in the wide-field neurons in the superficial SC (sSC). In either the Cdh13 null mutant or selective adult deletion within the wide-field neurons, there is a significant reduction of spine densities in the distal dendrites of these neurons in both sexes. Additionally, Cdh13 removal from presynaptic RGCs reduced dendritic spines in the postsynaptic wide-field neurons. Cdh13-expressing RGCs use differential mechanisms than αRGCs and On-Off Direction-Selective Ganglion Cells (ooDSGCs) to form specific retinotectal synapses. The results revealed a selective transneuronal interaction mediated by Cdh13 to maintain proper retinotectal synapses in vivo.
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Affiliation(s)
- Angela C Matcham
- Neuroscience Graduate Program, Department of Ophthalmology, Kavli Institute for Fundamental Neuroscience, University of California SanFrancisco, San Francisco 94143-2811, California
| | - Kenichi Toma
- Neuroscience Graduate Program, Department of Ophthalmology, Kavli Institute for Fundamental Neuroscience, University of California SanFrancisco, San Francisco 94143-2811, California
| | - Nicole Y Tsai
- Neuroscience Graduate Program, Department of Ophthalmology, Kavli Institute for Fundamental Neuroscience, University of California SanFrancisco, San Francisco 94143-2811, California
| | - Christina J Sze
- Neuroscience Graduate Program, Department of Ophthalmology, Kavli Institute for Fundamental Neuroscience, University of California SanFrancisco, San Francisco 94143-2811, California
| | - Pin-Yeh Lin
- Neuroscience Graduate Program, Department of Ophthalmology, Kavli Institute for Fundamental Neuroscience, University of California SanFrancisco, San Francisco 94143-2811, California
| | - Ilaria F Stewart
- Neuroscience Graduate Program, Department of Ophthalmology, Kavli Institute for Fundamental Neuroscience, University of California SanFrancisco, San Francisco 94143-2811, California
| | - Xin Duan
- Neuroscience Graduate Program, Department of Ophthalmology, Kavli Institute for Fundamental Neuroscience, University of California SanFrancisco, San Francisco 94143-2811, California
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Vagnozzi AN, Moore MT, López de Boer R, Agarwal A, Zampieri N, Landmesser LT, Philippidou P. Catenin signaling controls phrenic motor neuron development and function during a narrow temporal window. Front Neural Circuits 2023; 17:1121049. [PMID: 36895798 PMCID: PMC9988953 DOI: 10.3389/fncir.2023.1121049] [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: 12/11/2022] [Accepted: 02/06/2023] [Indexed: 02/25/2023] Open
Abstract
Phrenic Motor Column (PMC) neurons are a specialized subset of motor neurons (MNs) that provide the only motor innervation to the diaphragm muscle and are therefore essential for survival. Despite their critical role, the mechanisms that control phrenic MN development and function are not well understood. Here, we show that catenin-mediated cadherin adhesive function is required for multiple aspects of phrenic MN development. Deletion of β- and γ-catenin from MN progenitors results in perinatal lethality and a severe reduction in phrenic MN bursting activity. In the absence of catenin signaling, phrenic MN topography is eroded, MN clustering is lost and phrenic axons and dendrites fail to grow appropriately. Despite the essential requirement for catenins in early phrenic MN development, they appear to be dispensable for phrenic MN maintenance, as catenin deletion from postmitotic MNs does not impact phrenic MN topography or function. Our data reveal a fundamental role for catenins in PMC development and suggest that distinct mechanisms are likely to control PMC maintenance.
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Affiliation(s)
- Alicia N. Vagnozzi
- Department of Neurosciences, Case Western Reserve University, Cleveland, OH, United States
| | - Matthew T. Moore
- Department of Neurosciences, Case Western Reserve University, Cleveland, OH, United States
| | - Raquel López de Boer
- Department of Neurosciences, Case Western Reserve University, Cleveland, OH, United States
| | - Aambar Agarwal
- Department of Neurosciences, Case Western Reserve University, Cleveland, OH, United States
| | - Niccolò Zampieri
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany
| | - Lynn T. Landmesser
- Department of Neurosciences, Case Western Reserve University, Cleveland, OH, United States
| | - Polyxeni Philippidou
- Department of Neurosciences, Case Western Reserve University, Cleveland, OH, United States
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5
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Catenin signaling controls phrenic motor neuron development and function during a narrow temporal window. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.18.524559. [PMID: 36711833 PMCID: PMC9882252 DOI: 10.1101/2023.01.18.524559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Phrenic Motor Column (PMC) neurons are a specialized subset of motor neurons (MNs) that provide the only motor innervation to the diaphragm muscle and are therefore essential for survival. Despite their critical role, the mechanisms that control phrenic MN development and function are not well understood. Here, we show that catenin-mediated cadherin adhesive function is required for multiple aspects of phrenic MN development. Deletion of β - and γ -catenin from MN progenitors results in perinatal lethality and a severe reduction in phrenic MN bursting activity. In the absence of catenin signaling, phrenic MN topography is eroded, MN clustering is lost and phrenic axons and dendrites fail to grow appropriately. Despite the essential requirement for catenins in early phrenic MN development, they appear to be dispensable for phrenic MN maintenance, as catenin deletion from postmitotic MNs does not impact phrenic MN topography or function. Our data reveal a fundamental role for catenins in PMC development and suggest that distinct mechanisms are likely to control PMC maintenance.
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Qi C, Luo LD, Feng I, Ma S. Molecular mechanisms of synaptogenesis. Front Synaptic Neurosci 2022; 14:939793. [PMID: 36176941 PMCID: PMC9513053 DOI: 10.3389/fnsyn.2022.939793] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Accepted: 07/27/2022] [Indexed: 11/29/2022] Open
Abstract
Synapses are the basic units for information processing and storage in the nervous system. It is only when the synaptic connection is established, that it becomes meaningful to discuss the structure and function of a circuit. In humans, our unparalleled cognitive abilities are correlated with an increase in the number of synapses. Additionally, genes involved in synaptogenesis are also frequently associated with neurological or psychiatric disorders, suggesting a relationship between synaptogenesis and brain physiology and pathology. Thus, understanding the molecular mechanisms of synaptogenesis is the key to the mystery of circuit assembly and neural computation. Furthermore, it would provide therapeutic insights for the treatment of neurological and psychiatric disorders. Multiple molecular events must be precisely coordinated to generate a synapse. To understand the molecular mechanisms underlying synaptogenesis, we need to know the molecular components of synapses, how these molecular components are held together, and how the molecular networks are refined in response to neural activity to generate new synapses. Thanks to the intensive investigations in this field, our understanding of the process of synaptogenesis has progressed significantly. Here, we will review the molecular mechanisms of synaptogenesis by going over the studies on the identification of molecular components in synapses and their functions in synaptogenesis, how cell adhesion molecules connect these synaptic molecules together, and how neural activity mobilizes these molecules to generate new synapses. Finally, we will summarize the human-specific regulatory mechanisms in synaptogenesis and results from human genetics studies on synaptogenesis and brain disorders.
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Affiliation(s)
- Cai Qi
- Department of Neuroscience, Yale School of Medicine, New Haven, CT, United States
- *Correspondence: Cai Qi,
| | - Li-Da Luo
- Department of Neuroscience, Yale School of Medicine, New Haven, CT, United States
- Department of Cellular and Molecular Physiology, Program in Cellular Neuroscience, Neurodegeneration and Repair, Yale University School of Medicine, New Haven, CT, United States
| | - Irena Feng
- Boston University School of Medicine, Boston, MA, United States
| | - Shaojie Ma
- Department of Neuroscience, Yale School of Medicine, New Haven, CT, United States
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7
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Donta MS, Srivastava Y, McCrea PD. Delta-Catenin as a Modulator of Rho GTPases in Neurons. Front Cell Neurosci 2022; 16:939143. [PMID: 35860313 PMCID: PMC9289679 DOI: 10.3389/fncel.2022.939143] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2022] [Accepted: 06/09/2022] [Indexed: 12/03/2022] Open
Abstract
Small Rho GTPases are molecular switches that are involved in multiple processes including regulation of the actin cytoskeleton. These GTPases are activated (turned on) and inactivated (turned off) through various upstream effector molecules to carry out many cellular functions. One such upstream modulator of small Rho GTPase activity is delta-catenin, which is a protein in the p120-catenin subfamily that is enriched in the central nervous system. Delta-catenin affects small GTPase activity to assist in the developmental formation of dendrites and dendritic spines and to maintain them once they mature. As the dendritic arbor and spine density are crucial for synapse formation and plasticity, delta-catenin’s ability to modulate small Rho GTPases is necessary for proper learning and memory. Accordingly, the misregulation of delta-catenin and small Rho GTPases has been implicated in several neurological and non-neurological pathologies. While links between delta-catenin and small Rho GTPases have yet to be studied in many contexts, known associations include some cancers, Alzheimer’s disease (AD), Cri-du-chat syndrome, and autism spectrum disorder (ASD). Drawing from established studies and recent discoveries, this review explores how delta-catenin modulates small Rho GTPase activity. Future studies will likely elucidate how PDZ proteins that bind delta-catenin further influence small Rho GTPases, how delta-catenin may affect small GTPase activity at adherens junctions when bound to N-cadherin, mechanisms behind delta-catenin’s ability to modulate Rac1 and Cdc42, and delta-catenin’s ability to modulate small Rho GTPases in the context of diseases, such as cancer and AD.
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Affiliation(s)
- Maxsam S. Donta
- Department of Genetics, The University of Texas MD Anderson Cancer Center, Houston, TX, United States
- Program in Genetics and Epigenetics, The University of Texas MD Anderson Cancer Center University of Texas Health Science Center Houston Graduate School of Biomedical Science, Houston, TX, United States
- *Correspondence: Maxsam S. Donta,
| | - Yogesh Srivastava
- Department of Genetics, The University of Texas MD Anderson Cancer Center, Houston, TX, United States
| | - Pierre D. McCrea
- Department of Genetics, The University of Texas MD Anderson Cancer Center, Houston, TX, United States
- Program in Genetics and Epigenetics, The University of Texas MD Anderson Cancer Center University of Texas Health Science Center Houston Graduate School of Biomedical Science, Houston, TX, United States
- Program in Neuroscience, The University of Texas MD Anderson Cancer Center University of Texas Health Science Center Houston Graduate School of Biomedical Science, Houston, TX, United States
- Pierre D. McCrea,
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Inoue Y, Sawano T, Yamaguchi N, Inoue S, Takayama A, Nakazawa S, Inagaki S, Nakatani J, Tanaka H. Comparative distribution of
Arcadlin/Protocadherin‐8
mRNA in the intact and ischemic brains of adult mice. J Comp Neurol 2022; 530:2033-2055. [DOI: 10.1002/cne.25319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 02/24/2022] [Accepted: 03/07/2022] [Indexed: 11/12/2022]
Affiliation(s)
- Yosuke Inoue
- Pharmacology Laboratory Department of Biomedical Sciences, College of Life Sciences Ritsumeikan University Shiga Japan
| | - Toshinori Sawano
- Pharmacology Laboratory Department of Biomedical Sciences, College of Life Sciences Ritsumeikan University Shiga Japan
| | - Natsumi Yamaguchi
- Pharmacology Laboratory Department of Biomedical Sciences, College of Life Sciences Ritsumeikan University Shiga Japan
| | - Shota Inoue
- Pharmacology Laboratory Department of Biomedical Sciences, College of Life Sciences Ritsumeikan University Shiga Japan
| | - Akinori Takayama
- Pharmacology Laboratory Department of Biomedical Sciences, College of Life Sciences Ritsumeikan University Shiga Japan
| | - Shuma Nakazawa
- Pharmacology Laboratory Department of Biomedical Sciences, College of Life Sciences Ritsumeikan University Shiga Japan
| | - Shinobu Inagaki
- United Graduate School of Child Development Osaka University Suita Japan
- Department of Physical Therapy Osaka Yukioka College of Health Science Ibaraki Japan
| | - Jin Nakatani
- Pharmacology Laboratory Department of Biomedical Sciences, College of Life Sciences Ritsumeikan University Shiga Japan
| | - Hidekazu Tanaka
- Pharmacology Laboratory Department of Biomedical Sciences, College of Life Sciences Ritsumeikan University Shiga Japan
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Hernandez SJ, Fote G, Reyes-Ortiz AM, Steffan JS, Thompson LM. Cooperation of cell adhesion and autophagy in the brain: Functional roles in development and neurodegenerative disease. Matrix Biol Plus 2021; 12:100089. [PMID: 34786551 PMCID: PMC8579148 DOI: 10.1016/j.mbplus.2021.100089] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Revised: 09/11/2021] [Accepted: 10/18/2021] [Indexed: 12/19/2022] Open
Abstract
Cellular adhesive connections directed by the extracellular matrix (ECM) and maintenance of cellular homeostasis by autophagy are seemingly disparate functions that are molecularly intertwined, each regulating the other. This is an emerging field in the brain where the interplay between adhesion and autophagy functions at the intersection of neuroprotection and neurodegeneration. The ECM and adhesion proteins regulate autophagic responses to direct protein clearance and guide regenerative programs that go awry in brain disorders. Concomitantly, autophagic flux acts to regulate adhesion dynamics to mediate neurite outgrowth and synaptic plasticity with functional disruption contributed by neurodegenerative disease. This review highlights the cooperative exchange between cellular adhesion and autophagy in the brain during health and disease. As the mechanistic alliance between adhesion and autophagy has been leveraged therapeutically for metastatic disease, understanding overlapping molecular functions that direct the interplay between adhesion and autophagy might uncover therapeutic strategies to correct or compensate for neurodegeneration.
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Affiliation(s)
- Sarah J. Hernandez
- Neurobiology and Behavior, University of California Irvine, Irvine, CA 92697, USA
- Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, CA 92697, USA
| | - Gianna Fote
- Department of Biological Chemistry, University of California Irvine, Irvine, CA 92697, USA
| | - Andrea M. Reyes-Ortiz
- Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, CA 92697, USA
- Department of Biological Chemistry, University of California Irvine, Irvine, CA 92697, USA
| | - Joan S. Steffan
- Psychaitry and Human Behavior, University of California Irvine, Irvine, CA 92697, USA
- Institute of Memory Impairments and Neurological Disorders, University of California Irvine, Irvine, CA 92617, USA
| | - Leslie M. Thompson
- Neurobiology and Behavior, University of California Irvine, Irvine, CA 92697, USA
- Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, CA 92697, USA
- Department of Biological Chemistry, University of California Irvine, Irvine, CA 92697, USA
- Psychaitry and Human Behavior, University of California Irvine, Irvine, CA 92697, USA
- Institute of Memory Impairments and Neurological Disorders, University of California Irvine, Irvine, CA 92617, USA
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10
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Dutta P, Bharti P, Kumar J, Maiti S. Role of actin cytoskeleton in the organization and function of ionotropic glutamate receptors. Curr Res Struct Biol 2021; 3:277-289. [PMID: 34766008 PMCID: PMC8569634 DOI: 10.1016/j.crstbi.2021.10.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2021] [Revised: 09/04/2021] [Accepted: 10/09/2021] [Indexed: 12/22/2022] Open
Abstract
Neural networks with precise connection are compulsory for learning and memory. Various cellular events occur during the genesis of dendritic spines to their maturation, synapse formation, stabilization of the synapse, and proper signal transmission. The cortical actin cytoskeleton and its multiple regulatory proteins are crucial for the above cellular events. The different types of ionotropic glutamate receptors (iGluRs) present on the postsynaptic density (PSD) are also essential for learning and memory. Interaction of the iGluRs in association of their auxiliary proteins with actin cytoskeleton regulated by actin-binding proteins (ABPs) are required for precise long-term potentiation (LTP) and long-term depression (LTD). There has been a quest to understand the mechanistic detail of synapse function involving these receptors with dynamic actin cytoskeleton. A major, emerging area of investigation is the relationship between ABPs and iGluRs in synapse development. In this review we have summarized the current understanding of iGluRs functioning with respect to the actin cytoskeleton, scaffolding proteins, and their regulators. The AMPA, NMDA, Delta and Kainate receptors need the stable underlying actin cytoskeleton to anchor through synaptic proteins for precise synapse formation. The different types of ABPs present in neurons play a critical role in dynamizing/stabilizing the actin cytoskeleton needed for iGluRs function.
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Affiliation(s)
- Priyanka Dutta
- National Centre for Cell Science, Pune, Maharashtra, 411007, India
| | - Pratibha Bharti
- National Centre for Cell Science, Pune, Maharashtra, 411007, India
| | - Janesh Kumar
- National Centre for Cell Science, Pune, Maharashtra, 411007, India
| | - Sankar Maiti
- Indian Institute of Science Education and Research, Kolkata, 741246, India
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11
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Diaz A, Merino P, McCann P, Yepes MA, Quiceno LG, Torre E, Tomkins A, Zhang X, Hales CM, Tong FC, Yepes M. Urokinase-type plasminogen activator promotes N-cadherin-mediated synaptic recovery in the ischemic brain. J Cereb Blood Flow Metab 2021; 41:2381-2394. [PMID: 33757316 PMCID: PMC8393294 DOI: 10.1177/0271678x211002297] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Urokinase-type plasminogen activator (uPA) is a serine proteinase that catalyzes the generation of plasmin on the cell surface and activates cell signaling pathways that promote remodeling and repair. Neuronal cadherin (NCAD) is a transmembrane protein that in the mature brain mediates the formation of synaptic contacts in the II/III and V cortical layers. Our studies show that uPA is preferentially found in the II/III and V cortical laminae of the gyrencephalic cortex of the non-human primate. Furthermore, we found that in murine cerebral cortical neurons and induced pluripotent stem cell (iPSC)-derived neurons prepared from healthy human donors, most of this uPA is associated with pre-synaptic vesicles. Our in vivo experiments revealed that in both, the gyrencephalic cortex of the non-human primate and the lissecephalic murine brain, cerebral ischemia decreases the number of intact synaptic contacts and the expression of uPA and NCAD in a band of tissue surrounding the necrotic core. Additionally, our in vitro data show that uPA induces the synthesis of NCAD in cerebral cortical neurons, and in line with these observations, intravenous treatment with recombinant uPA three hours after the onset of cerebral ischemia induces NCAD-mediated repair of synaptic contacts in the area surrounding the necrotic core.
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Affiliation(s)
- Ariel Diaz
- Division of Neuropharmacology and Neurologic Diseases, Yerkes National Primate Research Center, Atlanta, GA, USA
| | - Paola Merino
- Division of Neuropharmacology and Neurologic Diseases, Yerkes National Primate Research Center, Atlanta, GA, USA
| | - Patrick McCann
- Division of Neuropharmacology and Neurologic Diseases, Yerkes National Primate Research Center, Atlanta, GA, USA
| | - Manuel A Yepes
- Division of Neuropharmacology and Neurologic Diseases, Yerkes National Primate Research Center, Atlanta, GA, USA
| | - Laura G Quiceno
- Department of Neurology & Center for Neurodegenerative Disease, Emory University, Atlanta, GA, USA
| | - Enrique Torre
- Division of Neuropharmacology and Neurologic Diseases, Yerkes National Primate Research Center, Atlanta, GA, USA
| | - Amelia Tomkins
- Division of Neuropharmacology and Neurologic Diseases, Yerkes National Primate Research Center, Atlanta, GA, USA
| | - Xiaodong Zhang
- Imaging Center, Yerkes National Primate Research Center, Atlanta, GA, USA
| | - Chadwick M Hales
- Department of Neurology & Center for Neurodegenerative Disease, Emory University, Atlanta, GA, USA
| | - Frank C Tong
- Departments of Radiology and Neurosurgery, Emory University, Atlanta, GA, USA
| | - Manuel Yepes
- Division of Neuropharmacology and Neurologic Diseases, Yerkes National Primate Research Center, Atlanta, GA, USA
- Department of Neurology & Center for Neurodegenerative Disease, Emory University, Atlanta, GA, USA
- Department of Neurology, Veterans Affairs Medical Center, Atlanta, GA, USA
- Manuel Yepes, Division of Neuropharmacology and Neurologic Diseases, Yerkes National Primate Research Center, 954 Gatewood Road-NE, Atlanta, GA 30329-4208, USA.
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12
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Kastian RF, Minegishi T, Baba K, Saneyoshi T, Katsuno-Kambe H, Saranpal S, Hayashi Y, Inagaki N. Shootin1a-mediated actin-adhesion coupling generates force to trigger structural plasticity of dendritic spines. Cell Rep 2021; 35:109130. [PMID: 34010643 DOI: 10.1016/j.celrep.2021.109130] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Revised: 03/09/2021] [Accepted: 04/22/2021] [Indexed: 12/19/2022] Open
Abstract
Dendritic spines constitute the major compartments of excitatory post-synapses. They undergo activity-dependent enlargement, which is thought to increase the synaptic efficacy underlying learning and memory. The activity-dependent spine enlargement requires activation of signaling pathways leading to promotion of actin polymerization within the spines. However, the molecular machinery that suffices for that structural plasticity remains unclear. Here, we demonstrate that shootin1a links polymerizing actin filaments in spines with the cell-adhesion molecules N-cadherin and L1-CAM, thereby mechanically coupling the filaments to the extracellular environment. Synaptic activation enhances shootin1a-mediated actin-adhesion coupling in spines. Promotion of actin polymerization is insufficient for the plasticity; the enhanced actin-adhesion coupling is required for polymerizing actin filaments to push against the membrane for spine enlargement. By integrating cell signaling, cell adhesion, and force generation into the current model of actin-based machinery, we propose molecular machinery that is sufficient to trigger the activity-dependent spine structural plasticity.
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Affiliation(s)
- Ria Fajarwati Kastian
- Laboratory of Systems Neurobiology and Medicine, Division of Biological Science, Nara Institute of Science and Technology, Ikoma, Nara 630-0192, Japan
| | - Takunori Minegishi
- Laboratory of Systems Neurobiology and Medicine, Division of Biological Science, Nara Institute of Science and Technology, Ikoma, Nara 630-0192, Japan
| | - Kentarou Baba
- Laboratory of Systems Neurobiology and Medicine, Division of Biological Science, Nara Institute of Science and Technology, Ikoma, Nara 630-0192, Japan
| | - Takeo Saneyoshi
- Department of Pharmacology, Kyoto University Graduate School of Medicine, Kyoto 606-8501, Japan
| | - Hiroko Katsuno-Kambe
- Laboratory of Systems Neurobiology and Medicine, Division of Biological Science, Nara Institute of Science and Technology, Ikoma, Nara 630-0192, Japan
| | - Singh Saranpal
- Laboratory of Systems Neurobiology and Medicine, Division of Biological Science, Nara Institute of Science and Technology, Ikoma, Nara 630-0192, Japan
| | - Yasunori Hayashi
- Department of Pharmacology, Kyoto University Graduate School of Medicine, Kyoto 606-8501, Japan
| | - Naoyuki Inagaki
- Laboratory of Systems Neurobiology and Medicine, Division of Biological Science, Nara Institute of Science and Technology, Ikoma, Nara 630-0192, Japan.
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13
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Ikuta R, Myoenzono K, Wasano J, Hamaguchi-Hamada K, Hamada S, Kurumata-Shigeto M. N-cadherin localization in taste buds of mouse circumvallate papillae. J Comp Neurol 2020; 529:2227-2242. [PMID: 33319419 DOI: 10.1002/cne.25090] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Revised: 12/03/2020] [Accepted: 12/04/2020] [Indexed: 01/03/2023]
Abstract
Taste buds, the receptor organs for taste, contain 50-100 taste bud cells. Although these cells undergo continuous turnover, the structural and functional integrity of taste buds is maintained. The molecular mechanisms by which synaptic connectivity between taste buds and afferent fibers is formed and maintained remain ambiguous. In the present study, we examined the localization of N-cadherin in the taste buds of the mouse circumvallate papillae because N-cadherin, one of the classical cadherins, is important for the formation and maintenance of synapses. At the light microscopic level, N-cadherin was predominantly detected in type II cells and nerve fibers in the connective tissues in and around the vallate papillae. At the ultrastructural level, N-cadherin immunoreactivity appears along the cell membrane and in the intracellular vesicles of type II cells. N-cadherin immunoreactivity also is evident in the membranes of afferent terminals at the contact sites to N-cadherin-positive type II cells. At channel type synapses between type II cells and nerve fibers, N-cadherin is present surrounding, but not within, the presumed neurotransmitter release zone, identified by large mitochondria apposed to the taste cells. The present results suggest that N-cadherin is important for the formation or maintenance of type II cell afferent synapses in taste buds.
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Affiliation(s)
- Rio Ikuta
- International College of Arts and Sciences, Fukuoka Women's University, Fukuoka, Japan
| | - Kanae Myoenzono
- International College of Arts and Sciences, Fukuoka Women's University, Fukuoka, Japan.,Humanome Lab., Inc., Tokyo, Japan
| | - Jun Wasano
- International College of Arts and Sciences, Fukuoka Women's University, Fukuoka, Japan
| | | | - Shun Hamada
- International College of Arts and Sciences, Fukuoka Women's University, Fukuoka, Japan
| | - Mami Kurumata-Shigeto
- International College of Arts and Sciences, Fukuoka Women's University, Fukuoka, Japan
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14
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Asih PR, Prikas E, Stefanoska K, Tan ARP, Ahel HI, Ittner A. Functions of p38 MAP Kinases in the Central Nervous System. Front Mol Neurosci 2020; 13:570586. [PMID: 33013322 PMCID: PMC7509416 DOI: 10.3389/fnmol.2020.570586] [Citation(s) in RCA: 79] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Accepted: 08/18/2020] [Indexed: 12/22/2022] Open
Abstract
Mitogen-activated protein (MAP) kinases are a central component in signaling networks in a multitude of mammalian cell types. This review covers recent advances on specific functions of p38 MAP kinases in cells of the central nervous system. Unique and specific functions of the four mammalian p38 kinases are found in all major cell types in the brain. Mechanisms of p38 activation and downstream phosphorylation substrates in these different contexts are outlined and how they contribute to functions of p38 in physiological and under disease conditions. Results in different model organisms demonstrated that p38 kinases are involved in cognitive functions, including functions related to anxiety, addiction behavior, neurotoxicity, neurodegeneration, and decision making. Finally, the role of p38 kinases in psychiatric and neurological conditions and the current progress on therapeutic inhibitors targeting p38 kinases are covered and implicate p38 kinases in a multitude of CNS-related physiological and disease states.
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Affiliation(s)
- Prita R Asih
- Dementia Research Centre, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW, Australia
| | - Emmanuel Prikas
- Dementia Research Centre, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW, Australia
| | - Kristie Stefanoska
- Dementia Research Centre, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW, Australia
| | - Amanda R P Tan
- Dementia Research Centre, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW, Australia
| | - Holly I Ahel
- Dementia Research Centre, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW, Australia
| | - Arne Ittner
- Dementia Research Centre, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW, Australia
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15
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Viale B, Song L, Petrenko V, Wenger Combremont AL, Contestabile A, Bocchi R, Salmon P, Carleton A, An L, Vutskits L, Kiss JZ. Transient Deregulation of Canonical Wnt Signaling in Developing Pyramidal Neurons Leads to Dendritic Defects and Impaired Behavior. Cell Rep 2020; 27:1487-1502.e6. [PMID: 31042475 DOI: 10.1016/j.celrep.2019.04.026] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Revised: 02/28/2019] [Accepted: 04/03/2019] [Indexed: 12/30/2022] Open
Abstract
During development, the precise implementation of molecular programs is a key determinant of proper dendritic development. Here, we demonstrate that canonical Wnt signaling is active in dendritic bundle-forming layer II pyramidal neurons of the rat retrosplenial cortex during dendritic branching and spine formation. Transient downregulation of canonical Wnt transcriptional activity during the early postnatal period irreversibly reduces dendritic arbor architecture, leading to long-lasting deficits in spatial exploration and/or navigation and spatial memory in the adult. During the late phase of dendritogenesis, canonical Wnt-dependent transcription regulates spine formation and maturation. We identify neurotrophin-3 as canonical Wnt target gene in regulating dendritogenesis. Our findings demonstrate how temporary imbalance in canonical Wnt signaling during specific time windows can result in irreversible dendritic defects, leading to abnormal behavior in the adult.
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Affiliation(s)
- Beatrice Viale
- Department of Basic Neurosciences, University of Geneva Medical School, 1211 Geneva 4, Switzerland
| | - Lin Song
- Department of Basic Neurosciences, University of Geneva Medical School, 1211 Geneva 4, Switzerland; School of Life Science and Biotechnology, Dalian University of Technology, Dalian, Liaoning 116024, China
| | - Volodymyr Petrenko
- Department of Basic Neurosciences, University of Geneva Medical School, 1211 Geneva 4, Switzerland
| | | | - Alessandro Contestabile
- Department of Basic Neurosciences, University of Geneva Medical School, 1211 Geneva 4, Switzerland
| | - Riccardo Bocchi
- Department of Basic Neurosciences, University of Geneva Medical School, 1211 Geneva 4, Switzerland
| | - Patrick Salmon
- Department of Basic Neurosciences, University of Geneva Medical School, 1211 Geneva 4, Switzerland
| | - Alan Carleton
- Department of Basic Neurosciences, University of Geneva Medical School, 1211 Geneva 4, Switzerland
| | - Lijia An
- School of Life Science and Biotechnology, Dalian University of Technology, Dalian, Liaoning 116024, China
| | - Laszlo Vutskits
- Department of Basic Neurosciences, University of Geneva Medical School, 1211 Geneva 4, Switzerland; Department of Anesthesiology, Pharmacology and Intensive Care, University Hospitals of Geneva, 1211 Geneva 4, Switzerland
| | - Jozsef Zoltan Kiss
- Department of Basic Neurosciences, University of Geneva Medical School, 1211 Geneva 4, Switzerland.
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16
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Synapse elimination activates a coordinated homeostatic presynaptic response in an autaptic circuit. Commun Biol 2020; 3:260. [PMID: 32444808 PMCID: PMC7244710 DOI: 10.1038/s42003-020-0963-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Accepted: 04/21/2020] [Indexed: 01/27/2023] Open
Abstract
The number of synapses present in a neuronal circuit is not fixed. Neurons must compensate for changes in connectivity caused by synaptic pruning, learning processes or pathological conditions through the constant adjustment of the baseline level of neurotransmission. Here, we show that cholinergic neurons grown in an autaptic circuit in the absence of glia sense the loss of half of their synaptic contacts triggered by exposure to peptide p4.2, a C-terminal fragment of SPARC. Synaptic elimination is driven by a reorganization of the periodic F-actin cytoskeleton present along neurites, and occurs without altering the density of postsynaptic receptors. Neurons recover baseline neurotransmission through a homeostatic presynaptic response that consists of the coordinated activation of rapid synapse formation and an overall potentiation of presynaptic calcium influx. These results demonstrate that neurons establishing autaptic connections continuously sense and adjust their synaptic output by tweaking the number of functional contacts and neurotransmitter release probability. Cecilia Velasco and Artur Llobet study how autapses respond to synapse elimination. They employ microisland cultures free of glial cells, treat with a SPARC-derived peptide and show that neurons forming autaptic circuits continuously sense and regulate the number of contacts and neurotransmitter release.
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17
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Cheng K, Chen YS, Yue CX, Zhang SM, Pei YP, Cheng GR, Liu D, Xu L, Dong HX, Zeng Y. Calsyntenin-1 Negatively Regulates ICAM5 Accumulation in Postsynaptic Membrane and Influences Dendritic Spine Maturation in a Mouse Model of Fragile X Syndrome. Front Neurosci 2019; 13:1098. [PMID: 31680833 PMCID: PMC6813673 DOI: 10.3389/fnins.2019.01098] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2019] [Accepted: 09/30/2019] [Indexed: 11/29/2022] Open
Abstract
Fragile X syndrome (FXS) is a neurodevelopmental disorder that causes intellectual disability, as well as the leading monogenic cause of autism spectrum disorders (ASD), in which neurons show aberrant dendritic spine structure. The reduction/absence of the functional FMRP protein, coded by the X-linked Fmr1 gene in humans, is responsible for the syndrome. Targets of FMRP, CLSTN1, and ICAM5, play critical roles in the maturation of dendritic spines, synapse formation and synaptic plasticity. However, the implication of CLSTN1 and ICAM5 in dendritic spine abnormalities and the underlying neuropathologic processes in FXS remain uninvestigated. In this study, we demonstrated that CLSTN1 co-localizes and co-transports with ICAM5 in cultured cortical neurons. Also we showed that shRNA-mediated downregulation of CLSTN1 in cultured WT neurons increases ICAM5 on the surface of synaptic membrane, subsequently affecting the maturation of dendritic spines. Whereas, normalization of CLSTN1 level in Fmr1 KO neurons reduces ICAM5 abundance and rescues impaired dendritic spine phenotypes. Most importantly, CLSTN1 protein is reduced in the postnatal medial prefrontal cortex of Fmr1 KO mice, which is correlated with increased ICAM5 levels on the surface of synapses and excessive filopodia-like spines. In conclusion, this study demonstrates that CLSTN1 plays a critical role in dendritic spine formation and maturation in FXS by regulating ICAM5 redistribution.
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Affiliation(s)
- Ke Cheng
- Brain and Cognition Research Institute, Wuhan University of Science and Technology, Wuhan, China.,Big Data Science and Engineering Research Institute, Wuhan University of Science and Technology, Wuhan, China
| | - Yu-Shan Chen
- Brain and Cognition Research Institute, Wuhan University of Science and Technology, Wuhan, China.,Big Data Science and Engineering Research Institute, Wuhan University of Science and Technology, Wuhan, China
| | - Chao-Xiong Yue
- Brain and Cognition Research Institute, Wuhan University of Science and Technology, Wuhan, China.,Big Data Science and Engineering Research Institute, Wuhan University of Science and Technology, Wuhan, China
| | - Si-Ming Zhang
- Brain and Cognition Research Institute, Wuhan University of Science and Technology, Wuhan, China.,Big Data Science and Engineering Research Institute, Wuhan University of Science and Technology, Wuhan, China
| | - Ya-Ping Pei
- Brain and Cognition Research Institute, Wuhan University of Science and Technology, Wuhan, China.,Big Data Science and Engineering Research Institute, Wuhan University of Science and Technology, Wuhan, China
| | - Gui-Rong Cheng
- Brain and Cognition Research Institute, Wuhan University of Science and Technology, Wuhan, China.,Big Data Science and Engineering Research Institute, Wuhan University of Science and Technology, Wuhan, China
| | - Dan Liu
- Brain and Cognition Research Institute, Wuhan University of Science and Technology, Wuhan, China.,Big Data Science and Engineering Research Institute, Wuhan University of Science and Technology, Wuhan, China
| | - Lang Xu
- Brain and Cognition Research Institute, Wuhan University of Science and Technology, Wuhan, China.,Big Data Science and Engineering Research Institute, Wuhan University of Science and Technology, Wuhan, China
| | - Hong-Xin Dong
- Brain and Cognition Research Institute, Wuhan University of Science and Technology, Wuhan, China.,Big Data Science and Engineering Research Institute, Wuhan University of Science and Technology, Wuhan, China.,Department of Psychiatry and Behavioral Sciences, Northwestern University, Chicago, IL, United States
| | - Yan Zeng
- Brain and Cognition Research Institute, Wuhan University of Science and Technology, Wuhan, China.,Big Data Science and Engineering Research Institute, Wuhan University of Science and Technology, Wuhan, China
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18
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Qin EC, Kandel ME, Liamas E, Shah TB, Kim C, Kaufman CD, Zhang ZJ, Popescu G, Gillette MU, Leckband DE, Kong H. Graphene oxide substrates with N-cadherin stimulates neuronal growth and intracellular transport. Acta Biomater 2019; 90:412-423. [PMID: 30951897 DOI: 10.1016/j.actbio.2019.04.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Revised: 03/12/2019] [Accepted: 04/01/2019] [Indexed: 12/23/2022]
Abstract
Intracellular transport is fundamental for neuronal function and development and is dependent on the formation of stable actin filaments. N-cadherin, a cell-cell adhesion protein, is actively involved in neuronal growth and actin cytoskeleton organization. Various groups have explored how neurons behaved on substrates engineered to present N-cadherin; however, few efforts have been made to examine how these surfaces modulate neuronal intracellular transport. To address this issue, we assembled a substrate to which recombinant N-cadherin molecules are physiosorbed using graphene oxide (GO) or reduced graphene oxide (rGO). N-cadherin physisorbed on GO and rGO led to a substantial enhancement of intracellular mass transport along neurites relative to N-cadherin on glass, due to increased neuronal adhesion, neurite extensions, dendritic arborization and glial cell adhesion. This study will be broadly useful for recreating active neural tissues in vitro and for improving our understanding of the development, homeostasis, and physiology of neurons. STATEMENT OF SIGNIFICANCE: Intracellular transport of proteins and chemical cues is extremely important for culturing neurons in vitro, as they replenish materials within and facilitate communication between neurons. Various studies have shown that intracellular transport is dependent on the formation of stable actin filaments. However, the extent to which cadherin-mediated cell-cell adhesion modulates intracellular transport is not heavily explored. In this study, N-cadherin was adsorbed onto graphene oxide-based substrates to understand the role of cadherin at a molecular level and the intracellular transport within cells was examined using spatial light interference microscopy. As such, the results of this study will serve to better understand and harness the role of cell-cell adhesion in neuron development and regeneration.
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19
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Pedone E, Marucci L. Role of β-Catenin Activation Levels and Fluctuations in Controlling Cell Fate. Genes (Basel) 2019; 10:genes10020176. [PMID: 30823613 PMCID: PMC6410200 DOI: 10.3390/genes10020176] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 02/18/2019] [Indexed: 12/12/2022] Open
Abstract
Cells have developed numerous adaptation mechanisms to external cues by controlling signaling-pathway activity, both qualitatively and quantitatively. The Wnt/β-catenin pathway is a highly conserved signaling pathway involved in many biological processes, including cell proliferation, differentiation, somatic cell reprogramming, development, and cancer. The activity of the Wnt/β-catenin pathway and the temporal dynamics of its effector β-catenin are tightly controlled by complex regulations. The latter encompass feedback loops within the pathway (e.g., a negative feedback loop involving Axin2, a β-catenin transcriptional target) and crosstalk interactions with other signaling pathways. Here, we provide a review shedding light on the coupling between Wnt/β-catenin activation levels and fluctuations across processes and cellular systems; in particular, we focus on development, in vitro pluripotency maintenance, and cancer. Possible mechanisms originating Wnt/β-catenin dynamic behaviors and consequently driving different cellular responses are also reviewed, and new avenues for future research are suggested.
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Affiliation(s)
- Elisa Pedone
- Department of Engineering Mathematics, University of Bristol, Bristol, BS8 1UB, UK.
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, BS8 1TD, UK.
| | - Lucia Marucci
- Department of Engineering Mathematics, University of Bristol, Bristol, BS8 1UB, UK.
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, BS8 1TD, UK.
- BrisSynBio, Bristol, BS8 1TQ, UK.
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20
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Mansel C, Fross S, Rose J, Dema E, Mann A, Hart H, Klawinski P, Vohra BPS. Lead exposure reduces survival, neuronal determination, and differentiation of P19 stem cells. Neurotoxicol Teratol 2019; 72:58-70. [PMID: 30776472 DOI: 10.1016/j.ntt.2019.01.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 01/12/2019] [Accepted: 01/29/2019] [Indexed: 01/09/2023]
Abstract
Lead (Pb) is a teratogen that poses health risks after acute and chronic exposure. Lead is deposited in the bones of adults and is continuously leached into the blood for decades. While this chronic lead exposure can have detrimental effects on adults such as high blood pressure and kidney damage, developing fetuses and young children are particularly vulnerable. During pregnancy, bone-deposited lead is released into the blood at increased rates and can cross the placental barrier, exposing the embryo to the toxin. Embryos exposed to lead display serious developmental and cognitive defects throughout life. Although studies have investigated lead's effect on late-stage embryos, few studies have examined how lead affects stem cell determination and differentiation. For example, it is unknown whether lead is more detrimental to neuronal determination or differentiation of stem cells. We sought to determine the effect of lead on the determination and differentiation of pluripotent embryonic testicular carcinoma (P19) cells into neurons. Our data indicate that lead exposure significantly inhibits the determination of P19 cells to the neuronal lineage by alteration of N-cadherin and Sox2 expression. We also observed that lead significantly alters subsequent neuronal and glial differentiation. Consequently, this research emphasizes the need to reduce public exposure to lead.
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Affiliation(s)
- Clayton Mansel
- William Jewell College, Department of Biology, Liberty, MO, United States of America
| | - Shaneann Fross
- William Jewell College, Department of Biology, Liberty, MO, United States of America
| | - Jesse Rose
- William Jewell College, Department of Biology, Liberty, MO, United States of America
| | - Emily Dema
- William Jewell College, Department of Biology, Liberty, MO, United States of America
| | - Alexis Mann
- William Jewell College, Department of Biology, Liberty, MO, United States of America
| | - Haley Hart
- William Jewell College, Department of Biology, Liberty, MO, United States of America
| | - Paul Klawinski
- William Jewell College, Department of Biology, Liberty, MO, United States of America
| | - Bhupinder P S Vohra
- William Jewell College, Department of Biology, Liberty, MO, United States of America.
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21
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Bassani S, Cwetsch AW, Gerosa L, Serratto GM, Folci A, Hall IF, Mazzanti M, Cancedda L, Passafaro M. The female epilepsy protein PCDH19 is a new GABAAR-binding partner that regulates GABAergic transmission as well as migration and morphological maturation of hippocampal neurons. Hum Mol Genet 2019; 27:1027-1038. [PMID: 29360992 PMCID: PMC5886308 DOI: 10.1093/hmg/ddy019] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Accepted: 01/04/2018] [Indexed: 01/15/2023] Open
Abstract
The PCDH19 gene (Xp22.1) encodes the cell-adhesion protein protocadherin-19 (PCDH19) and is responsible for a neurodevelopmental pathology characterized by female-limited epilepsy, cognitive impairment and autistic features, the pathogenic mechanisms of which remain to be elucidated. Here, we identified a new interaction between PCDH19 and GABAA receptor (GABAAR) alpha subunits in the rat brain. PCDH19 shRNA-mediated downregulation reduces GABAAR surface expression and affects the frequency and kinetics of miniature inhibitory postsynaptic currents (mIPSCs) in cultured hippocampal neurons. In vivo, PCDH19 downregulation impairs migration, orientation and dendritic arborization of CA1 hippocampal neurons and increases rat seizure susceptibility. In sum, these data indicate a role for PCDH19 in GABAergic transmission as well as migration and morphological maturation of neurons.
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Affiliation(s)
| | - Andrzej W Cwetsch
- Department of Neuroscience and Brain Technologies, Istituto Italiano di Tecnologia, Genoa 16163, Italy
| | - Laura Gerosa
- CNR Institute of Neuroscience, Milan 20129, Italy
| | | | | | | | - Michele Mazzanti
- Department of Bioscience, University of Milan, Milan 20133, Italy
| | - Laura Cancedda
- Department of Neuroscience and Brain Technologies, Istituto Italiano di Tecnologia, Genoa 16163, Italy.,Telethon Dulbecco Institute, Milan, Italy
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22
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Davila S, Liu P, Smith A, Marshall AG, Pedigo S. Spontaneous Calcium-Independent Dimerization of the Isolated First Domain of Neural Cadherin. Biochemistry 2018; 57:6404-6415. [PMID: 30387993 DOI: 10.1021/acs.biochem.8b00733] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Cadherins are calcium-dependent, transmembrane adhesion molecules that assemble through direct noncovalent association of their N-terminal extracellular modular domains. As the transmembrane component of adherens junctions, they indirectly link adherent cells' actin cytoskeletons. Here, we investigate the most distal extracellular domain of neural cadherin (N-cadherin), a protein required at excitatory synapses, the site of long-term potentiation. This domain is the site of the adhesive interface, and it forms a dimer spontaneously without binding calcium, a surprising finding given that calcium binding is required for proper physiological function. A critical tryptophan at position 2, W2, provides a spectroscopic probe for the "closed" monomer and strand-swapped dimer. Spectroscopic studies show that W2 remains docked in the two forms but has a different apparent interaction with the hydrophobic pocket. Size-exclusion chromatography was used to measure the levels of the monomer and dimer over time to study the kinetics and equilibria of the unexpected spontaneous dimer formation ( Kd = 130 μM; τ = 2 days at 4 °C). Our results support the idea that NCAD1 is missing critical contacts that facilitate the rapid exchange of the βA-strand. Furthermore, the monomer and dimer have equivalent and exceptionally high intrinsic stability for a 99-residue Ig-like domain with no internal disulfides ( Tm = 77 °C; Δ H = 85 kcal/mol). Ultimately, a complete analysis of synapse dynamics requires characterization of the kinetics and equilibria of N-cadherin. The studies reported here take a reductionist approach to understanding the essential biophysics of an atypical Ig-like domain that is the site of the adhesive interface of N-cadherin.
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Affiliation(s)
- Samantha Davila
- Department of Chemistry and Biochemistry , University of Mississippi , University , Mississippi 38677 , United States
| | - Peilu Liu
- Department of Chemistry & Biochemistry , Florida State University , Tallahassee , Florida 32306 , United States.,Ion Cyclotron Resonance Program, National High Magnetic Field Laboratory , Florida State University , Tallahassee , Florida 32310 , United States
| | - Alexis Smith
- Department of Chemistry and Biochemistry , University of Mississippi , University , Mississippi 38677 , United States
| | - Alan G Marshall
- Department of Chemistry & Biochemistry , Florida State University , Tallahassee , Florida 32306 , United States.,Ion Cyclotron Resonance Program, National High Magnetic Field Laboratory , Florida State University , Tallahassee , Florida 32310 , United States
| | - Susan Pedigo
- Department of Chemistry and Biochemistry , University of Mississippi , University , Mississippi 38677 , United States
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23
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Expression and Manipulation of the APC-β-Catenin Pathway During Peripheral Neuron Regeneration. Sci Rep 2018; 8:13197. [PMID: 30181617 PMCID: PMC6123411 DOI: 10.1038/s41598-018-31167-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Accepted: 08/03/2018] [Indexed: 02/07/2023] Open
Abstract
Molecules and pathways that suppress growth are expressed in postmitotic neurons, a potential advantage in mature neural networks, but a liability during regeneration. In this work, we probed the APC (adenomatous polyposis coli)-β-catenin partner pathway in adult peripheral sensory neurons during regeneration. APC had robust expression in the cytoplasm and perinuclear region of adult DRG sensory neurons both before and after axotomy injury. β-catenin was expressed in neuronal nuclei, neuronal cytoplasm and also in perineuronal satellite cells. In injured dorsal root ganglia (DRG) sensory neurons and their axons, we observed paradoxical APC upregulation, despite its role as an inhibitor of growth whereas β-catenin was downregulated. Inhibition of APC in adult sensory neurons and activation of β-catenin, LEF/TCF transcriptional factors were associated with increased neuronal plasticity in vitro. Local knockdown of APC, at the site of sciatic nerve crush injury enhanced evidence for electrophysiological, behavioural and structural regeneration in vivo. This was accompanied by upregulation of β-catenin. Collectively, the APC-β-catenin-LEF/TCF transcriptional pathway impacts intrinsic mechanisms of axonal regeneration and neuronal plasticity after injury, offering new options for addressing axon regeneration.
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24
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Abstract
The cadherin superfamily comprises a large, diverse collection of cell surface receptors that are expressed in the nervous system throughout development and have been shown to be essential for the proper assembly of the vertebrate nervous system. As our knowledge of each family member has grown, it has become increasingly clear that the functions of various cadherin subfamilies are intertwined: they can be present in the same protein complexes, impinge on the same developmental processes, and influence the same signaling pathways. This interconnectedness may illustrate a central way in which core developmental events are controlled to bring about the robust and precise assembly of neural circuitry.
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Affiliation(s)
- James D Jontes
- Department of Neuroscience, Ohio State University, Ohio 43210
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25
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Yamagata M, Duan X, Sanes JR. Cadherins Interact With Synaptic Organizers to Promote Synaptic Differentiation. Front Mol Neurosci 2018; 11:142. [PMID: 29760652 PMCID: PMC5936767 DOI: 10.3389/fnmol.2018.00142] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Accepted: 04/09/2018] [Indexed: 01/17/2023] Open
Abstract
Classical cadherins, a set of ~20 related recognition and signaling molecules, have been implicated in many aspects of neural development, including the formation and remodeling of synapses. Mechanisms underlying some of these steps have been studied by expressing N-cadherin (cdh2), a Type 1 cadherin, in heterologous cells, but analysis is complicated because widely used lines express cdh2 endogenously. We used CRISPR-mediated gene editing to generate a Human embryonic kidney (HEK)293 variant lacking Cdh2, then compared the behavior of rodent cortical and hippocampal neurons co-cultured with parental, cdh2 mutant and cdh2-rescued 293 lines. The comparison demonstrated that Cdh2 promotes neurite branching and that it is required for three synaptic organizers, neurologin1 (NLGL1), leucine-rich repeat transmembrane protein 2 (LRRtm2), and Cell Adhesion Molecule 1 (Cadm1/SynCAM) to stimulate presynaptic differentiation, assayed by clustering of synaptic vesicles at sites of neurite-293 cell contact. Similarly, Cdh2 is required for a presynaptic organizing molecule, Neurexin1β, to promote postsynaptic differentiation in dendrites. We also show that another Type I cadherin, Cdh4, and a Type II cadherin, Cdh6, can substitute for Cdh2 in these assays. Finally, we provide evidence that the effects of cadherins require homophilic interactions between neurites and the heterologous cells. Together, these results indicate that classical cadherins act together with synaptic organizers to promote synaptic differentiation, perhaps in part by strengthening the intracellular adhesion required for the organizers to act efficiently. We propose that cadherins promote high affinity contacts between appropriate partners, which then enable synaptic differentiation.
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Affiliation(s)
- Masahito Yamagata
- Center for Brain Science and Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA, United States
| | - Xin Duan
- Center for Brain Science and Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA, United States
| | - Joshua R Sanes
- Center for Brain Science and Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA, United States
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26
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Gladkov A, Grinchuk O, Pigareva Y, Mukhina I, Kazantsev V, Pimashkin A. Theta rhythm-like bidirectional cycling dynamics of living neuronal networks in vitro. PLoS One 2018; 13:e0192468. [PMID: 29415033 PMCID: PMC5802926 DOI: 10.1371/journal.pone.0192468] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Accepted: 01/24/2018] [Indexed: 12/12/2022] Open
Abstract
The phenomena of synchronization, rhythmogenesis and coherence observed in brain networks are believed to be a dynamic substrate for cognitive functions such as learning and memory. However, researchers are still debating whether the rhythmic activity emerges from the network morphology that developed during neurogenesis or as a result of neuronal dynamics achieved under certain conditions. In the present study, we observed self-organized spiking activity that converged to long, complex and rhythmically repeated superbursts in neural networks formed by mature hippocampal cultures with a high cellular density. The superburst lasted for tens of seconds and consisted of hundreds of short (50-100 ms) small bursts with a high spiking rate of 139.0 ± 78.6 Hz that is associated with high-frequency oscillations in the hippocampus. In turn, the bursting frequency represents a theta rhythm (11.2 ± 1.5 Hz). The distribution of spikes within the bursts was non-random, representing a set of well-defined spatio-temporal base patterns or motifs. The long superburst was classified into two types. Each type was associated with a unique direction of spike propagation and, hence, was encoded by a binary sequence with random switching between the two "functional" states. The precisely structured bidirectional rhythmic activity that developed in self-organizing cultured networks was quite similar to the activity observed in the in vivo experiments.
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Affiliation(s)
- Arseniy Gladkov
- Laboratory of Neuroengineering, Center of Translational Technologies, Lobachevsky State University of Nizhni Novgorod, Nizhny Novgorod, Russia
- Cell Technology Department, Central Research Laboratory, Nizhny Novgorod State Medical Academy, Nizhny Novgorod, Russia
| | - Oleg Grinchuk
- Information Science and Technology Department, Skolkovo Institute of Science and Technology, Moscow, Russia
| | - Yana Pigareva
- Laboratory of Neuroengineering, Center of Translational Technologies, Lobachevsky State University of Nizhni Novgorod, Nizhny Novgorod, Russia
| | - Irina Mukhina
- Laboratory of Neuroengineering, Center of Translational Technologies, Lobachevsky State University of Nizhni Novgorod, Nizhny Novgorod, Russia
- Cell Technology Department, Central Research Laboratory, Nizhny Novgorod State Medical Academy, Nizhny Novgorod, Russia
| | - Victor Kazantsev
- Laboratory of Neuroengineering, Center of Translational Technologies, Lobachevsky State University of Nizhni Novgorod, Nizhny Novgorod, Russia
| | - Alexey Pimashkin
- Laboratory of Neuroengineering, Center of Translational Technologies, Lobachevsky State University of Nizhni Novgorod, Nizhny Novgorod, Russia
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27
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Zobel K, Choi SE, Minakova R, Gocyla M, Offenhäusser A. N-Cadherin modified lipid bilayers promote neural network formation and circuitry. SOFT MATTER 2017; 13:8096-8107. [PMID: 29085948 DOI: 10.1039/c7sm01214d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Neural adhesion, maturation, and the correct wiring of the brain to establish each neuron's intended connectivity are controlled by complex interactions of bioactive molecules such as ligands, growth factors, or enzymes. The correct pairing of adjacent neurons is thought to be highly regulated by ligand-mediated cell-cell adhesion proteins, which are known to induce signaling activities. We developed a new platform consisting of supported lipid bilayers incorporated with Fc-chimera synaptic proteins like ephrinA5 or N-cadherin. We extensively characterized their function employing a quartz crystal microbalance with dissipation (QCM-D), calcium imaging, and immunofluorescence analysis. Our biomimetic platform has been shown to promote neural cell adhesion and to improve neural maturation at day in vitro 7 (DIV7) as indicated by an elevated expression of synaptophysin.
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Affiliation(s)
- K Zobel
- Institute of Bioelectronics (ICS-8), Forschungszentrum Juelich, Wilhelm-Johnen Straße, 52425 Juelich, Germany.
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28
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Matsuyama K, Seta Y, Kataoka S, Nakatomi M, Toyono T, Kawamoto T. Expression of N-cadherin and cell surface molecules in the taste buds of mouse circumvallate papillae. J Oral Biosci 2017. [DOI: 10.1016/j.job.2017.09.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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29
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Ganief T, Gqamana P, Garnett S, Hoare J, Stein DJ, Joska J, Soares N, Blackburn JM. Quantitative proteomic analysis of HIV-1 Tat-induced dysregulation in SH-SY5Y neuroblastoma cells. Proteomics 2017; 17. [PMID: 28101920 DOI: 10.1002/pmic.201600236] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Revised: 12/23/2016] [Accepted: 01/12/2017] [Indexed: 11/11/2022]
Abstract
Despite affecting up to 70% of HIV-positive patients and being the leading cause of dementia in patients under 40 years, the molecular mechanisms involved in the onset of HIV-associated neurocognitive disorders (HAND) are not well understood. To address this, we performed SILAC-based quantitative proteomic analysis on HIV-Tat treated SH-SY5Y neuroblastoma cells. Isolated protein was fractionated by SDS-PAGE and analyzed by nLC-MS/MS on an Orbitrap Velos. Using MaxQuant, we identified and quantified 3077 unique protein groups, of which 407 were differentially regulated. After applying an additional standard deviation-based cutoff, 29 of these were identified as highly significantly and stably dysregulated. GO term analysis shows dysregulation in both protein translation machinery as well as cytoskeletal regulation that have both been implicated in other dementias. In addition, several key cytoskeletal regulatory proteins such as ARHGEF17, the Rho GTPase, SHROOM3, and CMRP1 are downregulated. Together, these data demonstrate that HIV-Tat can dysregulate neuronal cytoskeletal regulatory proteins that could lead to the major HAND clinical manifestation-synapse loss.
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Affiliation(s)
- Tariq Ganief
- Department of Integrative Biomedical Sciences, University of Cape Town, South Africa
| | - Putuma Gqamana
- Department of Integrative Biomedical Sciences, University of Cape Town, South Africa
| | - Shaun Garnett
- Department of Integrative Biomedical Sciences, University of Cape Town, South Africa
| | - Jackie Hoare
- Department of Psychiatry, University of Cape Town, South Africa
| | - Dan J Stein
- Department of Psychiatry, University of Cape Town, South Africa.,MRC Unit on Anxiety and Stress Disorders, University of Cape Town, South Africa
| | - John Joska
- Department of Psychiatry, University of Cape Town, South Africa
| | - Nelson Soares
- Department of Integrative Biomedical Sciences, University of Cape Town, South Africa
| | - Jonathan M Blackburn
- Department of Integrative Biomedical Sciences, University of Cape Town, South Africa.,Institute of Infectious Disease and Molecular Medicine, University of Cape Town, South Africa
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30
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Emerging Synaptic Molecules as Candidates in the Etiology of Neurological Disorders. Neural Plast 2017; 2017:8081758. [PMID: 28331639 PMCID: PMC5346360 DOI: 10.1155/2017/8081758] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Accepted: 02/06/2017] [Indexed: 01/06/2023] Open
Abstract
Synapses are complex structures that allow communication between neurons in the central nervous system. Studies conducted in vertebrate and invertebrate models have contributed to the knowledge of the function of synaptic proteins. The functional synapse requires numerous protein complexes with specialized functions that are regulated in space and time to allow synaptic plasticity. However, their interplay during neuronal development, learning, and memory is poorly understood. Accumulating evidence links synapse proteins to neurodevelopmental, neuropsychiatric, and neurodegenerative diseases. In this review, we describe the way in which several proteins that participate in cell adhesion, scaffolding, exocytosis, and neurotransmitter reception from presynaptic and postsynaptic compartments, mainly from excitatory synapses, have been associated with several synaptopathies, and we relate their functions to the disease phenotype.
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31
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Mills F, Globa AK, Liu S, Cowan CM, Mobasser M, Phillips AG, Borgland SL, Bamji SX. Cadherins mediate cocaine-induced synaptic plasticity and behavioral conditioning. Nat Neurosci 2017; 20:540-549. [PMID: 28192395 PMCID: PMC5373847 DOI: 10.1038/nn.4503] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2016] [Accepted: 01/13/2017] [Indexed: 02/06/2023]
Abstract
Drugs of abuse alter synaptic connections in the ‘reward circuit’ of the brain, which leads to long-lasting behavioral changes that underlie addiction. Here we show that cadherin adhesion molecules play a critical role in mediating synaptic plasticity and behavioral changes driven by cocaine. We demonstrate that cadherin is essential for long-term potentiation (LTP) in the ventral tegmental area (VTA), and is recruited to the synaptic membrane of excitatory inputs onto dopaminergic neurons following cocaine-mediated behavioral conditioning. Furthermore, we show that stabilization of cadherin at the membrane of these synapses blocks cocaine-induced synaptic plasticity, leading to a significant reduction in conditioned place preference induced by cocaine. Our findings identify cadherins and associated molecules as targets of interest for understanding pathological plasticity associated with addiction.
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Affiliation(s)
- Fergil Mills
- Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - Andrea K Globa
- Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - Shuai Liu
- Department of Physiology and Pharmacology, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
| | - Catherine M Cowan
- Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - Mahsan Mobasser
- Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - Anthony G Phillips
- Department of Psychiatry and Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, British Columbia, Canada
| | - Stephanie L Borgland
- Department of Physiology and Pharmacology, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
| | - Shernaz X Bamji
- Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, British Columbia, Canada
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32
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Lin YC, Frei JA, Kilander MBC, Shen W, Blatt GJ. A Subset of Autism-Associated Genes Regulate the Structural Stability of Neurons. Front Cell Neurosci 2016; 10:263. [PMID: 27909399 PMCID: PMC5112273 DOI: 10.3389/fncel.2016.00263] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Accepted: 10/28/2016] [Indexed: 12/15/2022] Open
Abstract
Autism spectrum disorder (ASD) comprises a range of neurological conditions that affect individuals’ ability to communicate and interact with others. People with ASD often exhibit marked qualitative difficulties in social interaction, communication, and behavior. Alterations in neurite arborization and dendritic spine morphology, including size, shape, and number, are hallmarks of almost all neurological conditions, including ASD. As experimental evidence emerges in recent years, it becomes clear that although there is broad heterogeneity of identified autism risk genes, many of them converge into similar cellular pathways, including those regulating neurite outgrowth, synapse formation and spine stability, and synaptic plasticity. These mechanisms together regulate the structural stability of neurons and are vulnerable targets in ASD. In this review, we discuss the current understanding of those autism risk genes that affect the structural connectivity of neurons. We sub-categorize them into (1) cytoskeletal regulators, e.g., motors and small RhoGTPase regulators; (2) adhesion molecules, e.g., cadherins, NCAM, and neurexin superfamily; (3) cell surface receptors, e.g., glutamatergic receptors and receptor tyrosine kinases; (4) signaling molecules, e.g., protein kinases and phosphatases; and (5) synaptic proteins, e.g., vesicle and scaffolding proteins. Although the roles of some of these genes in maintaining neuronal structural stability are well studied, how mutations contribute to the autism phenotype is still largely unknown. Investigating whether and how the neuronal structure and function are affected when these genes are mutated will provide insights toward developing effective interventions aimed at improving the lives of people with autism and their families.
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Affiliation(s)
- Yu-Chih Lin
- Laboratory of Neuronal Connectivity, Program in Neuroscience, Hussman Institute for Autism, Baltimore MD, USA
| | - Jeannine A Frei
- Laboratory of Neuronal Connectivity, Program in Neuroscience, Hussman Institute for Autism, Baltimore MD, USA
| | - Michaela B C Kilander
- Laboratory of Neuronal Connectivity, Program in Neuroscience, Hussman Institute for Autism, Baltimore MD, USA
| | - Wenjuan Shen
- Laboratory of Neuronal Connectivity, Program in Neuroscience, Hussman Institute for Autism, Baltimore MD, USA
| | - Gene J Blatt
- Laboratory of Autism Neurocircuitry, Program in Neuroscience, Hussman Institute for Autism, Baltimore MD, USA
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33
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N-Cadherin is Involved in Neuronal Activity-Dependent Regulation of Myelinating Capacity of Zebrafish Individual Oligodendrocytes In Vivo. Mol Neurobiol 2016; 54:6917-6930. [PMID: 27771903 DOI: 10.1007/s12035-016-0233-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2016] [Accepted: 10/16/2016] [Indexed: 02/07/2023]
Abstract
Stimulating neuronal activity increases myelin sheath formation by individual oligodendrocytes, but how myelination is regulated by neuronal activity in vivo is still not fully understood. While in vitro studies have revealed the important role of N-cadherin in myelination, our understanding in vivo remains quite limited. To obtain the role of N-cadherin during activity-dependent regulation of myelinating capacity of individual oligodendrocytes, we successfully built an in vivo dynamic imaging model of the Mauthner cell at the subcellular structure level in the zebrafish central nervous system. Enhanced green fluorescent protein (EGFP)-tagged N-cadherin was used to visualize the stable accumulations and mobile transports of N-cadherin by single-cell electroporation at the single-cell level. We found that pentylenetetrazol (PTZ) significantly enhanced the accumulation of N-cadherin in Mauthner axons, a response that was paralleled by enhanced sheath number per oligodendrocytes. By offsetting this phenotype using oligopeptide (AHAVD) which blocks the function of N-cadherin, we showed that PTZ regulates myelination in an N-cadherin-dependent manner. What is more, we further suggested that PTZ influences N-cadherin and myelination via a cAMP pathway. Consequently, our data indicated that N-cadherin is involved in neuronal activity-dependent regulation of myelinating capacity of zebrafish individual oligodendrocytes in vivo.
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Abstract
Neurons are highly polarized specialized cells. Neuronal integrity and functional roles are critically dependent on dendritic architecture and synaptic structure, function and plasticity. The cadherins are glycosylated transmembrane proteins that form cell adhesion complexes in various tissues. They are associated with a group of cytosolic proteins, the catenins. While the functional roles of the complex have been extensively investigates in non-neuronal cells, it is becoming increasingly clear that components of the complex have critical roles in regulating dendritic and synaptic architecture, function and plasticity in neurons. Consistent with these functional roles, aberrations in components of the complex have been implicated in a variety of neurodevelopmental disorders. In this review, we discuss the roles of the classical cadherins and catenins in various aspects of dendrite and synapse architecture and function and their relevance to human neurological disorders. Cadherins are glycosylated transmembrane proteins that were initially identified as Ca(2+)-dependent cell adhesion molecules. They are present on plasma membrane of a variety of cell types from primitive metazoans to humans. In the past several years, it has become clear that in addition to providing mechanical adhesion between cells, cadherins play integral roles in tissue morphogenesis and homeostasis. The cadherin family is composed of more than 100 members and classified into several subfamilies, including classical cadherins and protocadherins. Several of these cadherin family members have been implicated in various aspects of neuronal development and function. (1-3) The classical cadherins are associated with a group of cytosolic proteins, collectively called the catenins. While the functional roles of the cadherin-catenin cell adhesion complex have been extensively investigated in epithelial cells, it is now clear that components of the complex are well expressed in central neurons at different stages during development. (4,5) Recent exciting studies have shed some light on the functional roles of cadherins and catenins in central neurons. In this review, we will provide a brief overview of the cadherin superfamily, describe cadherin family members expressed in central neurons, cadherin-catenin complexes in central neurons and then focus on role of the cadherin-catenin complex in dendrite morphogenesis and synapse morphogenesis, function and plasticity. The final section is dedicated to discussion of the emerging list of neural disorders linked to cadherins and catenins. While the roles of cadherins and catenins have been examined in several different types of neurons, the focus of this review is their role in mammalian central neurons, particularly those of the cortex and hippocampus. Accompanying this review is a series of excellent reviews targeting the roles of cadherins and protocadherins in other aspects of neural development.
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Affiliation(s)
- Eunju Seong
- a Developmental Neuroscience; Munroe-Meyer Institute; University of Nebraska Medical Center ; Omaha , NE USA
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35
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de Wit J, Ghosh A. Specification of synaptic connectivity by cell surface interactions. Nat Rev Neurosci 2015; 17:22-35. [PMID: 26656254 DOI: 10.1038/nrn.2015.3] [Citation(s) in RCA: 186] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The molecular diversification of cell surface molecules has long been postulated to impart specific surface identities on neuronal cell types. The existence of unique cell surface identities would allow neurons to distinguish one another and connect with their appropriate target cells. Although progress has been made in identifying cell type-specific surface molecule repertoires and in characterizing their extracellular interactions, determining how this molecular diversity contributes to the precise wiring of neural circuitry has proven challenging. Here, we review the role of the cadherin, neurexin, immunoglobulin and leucine-rich repeat protein superfamilies in the specification of connectivity. The emerging evidence suggests that the concerted actions of these proteins may critically contribute to the assembly of neural circuits.
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Affiliation(s)
- Joris de Wit
- VIB Center for the Biology of Disease and Center for Human Genetics, KU Leuven, Herestraat 49, 3000 Leuven, Belgium
| | - Anirvan Ghosh
- Neuroscience Discovery, Roche Innovation Center Basel, F. Hoffman-La Roche, Grenzacherstrasse 124, 4070 Basel, Switzerland
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36
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Shinoe T, Goda Y. Tuning synapses by proteolytic remodeling of the adhesive surface. Curr Opin Neurobiol 2015; 35:148-55. [DOI: 10.1016/j.conb.2015.08.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2015] [Revised: 07/17/2015] [Accepted: 08/04/2015] [Indexed: 10/23/2022]
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37
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Ichinose S, Ogawa T, Hirokawa N. Mechanism of Activity-Dependent Cargo Loading via the Phosphorylation of KIF3A by PKA and CaMKIIa. Neuron 2015; 87:1022-35. [PMID: 26335646 DOI: 10.1016/j.neuron.2015.08.008] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Revised: 06/30/2015] [Accepted: 07/31/2015] [Indexed: 12/14/2022]
Abstract
A regulated mechanism of cargo loading is crucial for intracellular transport. N-cadherin, a synaptic adhesion molecule that is critical for neuronal function, must be precisely transported to dendritic spines in response to synaptic activity and plasticity. However, the mechanism of activity-dependent cargo loading remains unclear. To elucidate this mechanism, we investigated the activity-dependent transport of N-cadherin via its transporter, KIF3A. First, by comparing KIF3A-bound cargo vesicles with unbound KIF3A, we identified critical KIF3A phosphorylation sites and specific kinases, PKA and CaMKIIa, using quantitative phosphoanalyses. Next, mutagenesis and kinase inhibitor experiments revealed that N-cadherin transport was enhanced via phosphorylation of the KIF3A C terminus, thereby increasing cargo-loading activity. Furthermore, N-cadherin transport was enhanced during homeostatic upregulation of synaptic strength, triggered by chronic inactivation by TTX. We propose the first model of activity-dependent cargo loading, in which phosphorylation of the KIF3A C terminus upregulates the loading and transport of N-cadherin in homeostatic synaptic plasticity.
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Affiliation(s)
- Sotaro Ichinose
- Department of Cell Biology and Anatomy, Graduate School of Medicine, University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Tadayuki Ogawa
- Department of Cell Biology and Anatomy, Graduate School of Medicine, University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Nobutaka Hirokawa
- Department of Cell Biology and Anatomy, Graduate School of Medicine, University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan; Center of Excellence in Genome Medicine Research, King Abdulaziz University, Jeddah 21589, Saudi Arabia.
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38
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Haque A, Adnan N, Motazedian A, Akter F, Hossain S, Kutsuzawa K, Nag K, Kobatake E, Akaike T. An Engineered N-Cadherin Substrate for Differentiation, Survival, and Selection of Pluripotent Stem Cell-Derived Neural Progenitors. PLoS One 2015; 10:e0135170. [PMID: 26244942 PMCID: PMC4526632 DOI: 10.1371/journal.pone.0135170] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Accepted: 07/18/2015] [Indexed: 11/18/2022] Open
Abstract
For stem cell-based treatment of neurodegenerative diseases a better understanding of key developmental signaling pathways and robust techniques for producing neurons with highest homogeneity are required. In this study, we demonstrate a method using N-cadherin-based biomimetic substrate to promote the differentiation of mouse embryonic stem cell (ESC)- and induced pluripotent stem cell (iPSC)-derived neural progenitor cells (NPCs) without exogenous neuro-inductive signals. We showed that substrate-dependent activation of N-cadherin reduces Rho/ROCK activation and β-catenin expression, leading to the stimulation of neurite outgrowth and conversion into cells expressing neural/glial markers. Besides, plating dissociated cells on N-cadherin substrate can significantly increase the differentiation yield via suppression of dissociation-induced Rho/ROCK-mediated apoptosis. Because undifferentiated ESCs and iPSCs have low affinity to N-cadherin, plating dissociated cells on N-cadherin-coated substrate increase the homogeneity of differentiation by purging ESCs and iPSCs (~30%) from a mixture of undifferentiated cells with NPCs. Using this label-free cell selection approach we enriched differentiated NPCs plated as monolayer without ROCK inhibitor. Therefore, N-cadherin biomimetic substrate provide a powerful tool for basic study of cell—material interaction in a spatially defined and substrate-dependent manner. Collectively, our approach is efficient, robust and cost effective to produce large quantities of differentiated cells with highest homogeneity and applicable to use with other types of cells.
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Affiliation(s)
- Amranul Haque
- Department of Biomolecular Engineering, Tokyo Institute of Technology, Yokohama, Japan
| | - Nihad Adnan
- Department of Biomolecular Engineering, Tokyo Institute of Technology, Yokohama, Japan
| | - Ali Motazedian
- Department of Biomolecular Engineering, Tokyo Institute of Technology, Yokohama, Japan
| | - Farhima Akter
- Department of Biological Information, Tokyo Institute of Technology, Yokohama, Japan
| | - Sharif Hossain
- Department of Biomolecular Engineering, Tokyo Institute of Technology, Yokohama, Japan
| | - Koichi Kutsuzawa
- Department of Biomolecular Engineering, Tokyo Institute of Technology, Yokohama, Japan
| | - Kakon Nag
- Department of Biomolecular Engineering, Tokyo Institute of Technology, Yokohama, Japan
| | - Eiry Kobatake
- Department of Biological Information, Tokyo Institute of Technology, Yokohama, Japan
| | - Toshihiro Akaike
- Department of Biomolecular Engineering, Tokyo Institute of Technology, Yokohama, Japan
- * E-mail:
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39
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Burette AC, Phend KD, Burette S, Lin Q, Liang M, Foltz G, Taylor N, Wang Q, Brandon NJ, Bates B, Ehlers MD, Weinberg RJ. Organization of TNIK in dendritic spines. J Comp Neurol 2015; 523:1913-24. [PMID: 25753355 DOI: 10.1002/cne.23770] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Revised: 02/25/2015] [Accepted: 02/26/2015] [Indexed: 01/16/2023]
Abstract
Tumor necrosis factor receptor-associated factor 2 (TRAF2)- and noncatalytic region of tyrosine kinase (NCK)-interacting kinase (TNIK) has been identified as an interactor in the psychiatric risk factor, Disrupted in Schizophrenia 1 (DISC1). As a step toward deciphering its function in the brain, we performed high-resolution light and electron microscopic immunocytochemistry. We demonstrate here that TNIK is expressed in neurons throughout the adult mouse brain. In striatum and cerebral cortex, TNIK concentrates in dendritic spines, especially in the vicinity of the lateral edge of the synapse. Thus, TNIK is highly enriched at a microdomain critical for glutamatergic signaling.
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Affiliation(s)
- Alain C Burette
- Department of Cell Biology & Physiology, University of North Carolina, Chapel Hill, North Carolina, 27599
| | - Kristen D Phend
- Department of Cell Biology & Physiology, University of North Carolina, Chapel Hill, North Carolina, 27599
| | - Susan Burette
- Department of Cell Biology & Physiology, University of North Carolina, Chapel Hill, North Carolina, 27599
| | - Qingcong Lin
- Shenogen Pharma Group, Beijing, People's Republic of China 102206
| | - Musen Liang
- Department of Pharmacokinetics, Dynamics, and Metabolism, Pfizer, Andover, Massachusetts 01810
| | - Gretchen Foltz
- Clinical Research Unit, Pfizer, New Haven, Connecticut 06511
| | - Noël Taylor
- Biomarker and Personalized Medicine Group, Eisai Product Creation Systems, Eisai, Andover, Massachusetts 01810
| | - Qi Wang
- Neuroscience Research Unit, Pfizer, Cambridge, Massachusetts 02139
| | | | - Brian Bates
- Centers for Therapeutic Innovation, Pfizer, Boston, Massachusetts 02115
| | - Michael D Ehlers
- Neuroscience Research Unit, Pfizer, Cambridge, Massachusetts 02139
| | - Richard J Weinberg
- Department of Cell Biology & Physiology, University of North Carolina, Chapel Hill, North Carolina, 27599.,Neuroscience Center, University of North Carolina, Chapel Hill, North Carolina, 27599
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High B, Cole AA, Chen X, Reese TS. Electron microscopic tomography reveals discrete transcleft elements at excitatory and inhibitory synapses. Front Synaptic Neurosci 2015; 7:9. [PMID: 26113817 PMCID: PMC4461817 DOI: 10.3389/fnsyn.2015.00009] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Accepted: 05/28/2015] [Indexed: 12/24/2022] Open
Abstract
Electron microscopy has revealed an abundance of material in the clefts of synapses in the mammalian brain, and the biochemical and functional characteristics of proteins occupying synaptic clefts are well documented. However, the detailed spatial organization of the proteins in the synaptic clefts remains unclear. Electron microscope tomography provides a way to delineate and map the proteins spanning the synaptic cleft because freeze substitution preserves molecular details with sufficient contrast to visualize individual cleft proteins. Segmentation and rendering of electron dense material connected across the cleft reveals discrete structural elements that are readily classified into five types at excitatory synapses and four types at inhibitory synapses. Some transcleft elements resemble shapes and sizes of known proteins and could represent single dimers traversing the cleft. Some of the types of cleft elements at inhibitory synapses roughly matched the structure and proportional frequency of cleft elements at excitatory synapses, but the patterns of deployments in the cleft are quite different. Transcleft elements at excitatory synapses were often evenly dispersed in clefts of uniform (18 nm) width but some types show preference for the center or edges of the cleft. Transcleft elements at inhibitory synapses typically were confined to a peripheral region of the cleft where it narrowed to only 6 nm wide. Transcleft elements in both excitatory and inhibitory synapses typically avoid places where synaptic vesicles attach to the presynaptic membrane. These results illustrate that elements spanning synaptic clefts at excitatory and inhibitory synapses consist of distinct structures arranged by type in a specific but different manner at excitatory and inhibitory synapses.
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Affiliation(s)
- Brigit High
- Laboratory of Neurobiology, National Institute of Neurological Disorders and Strokes, National Institutes of Health Bethesda, MD, USA
| | - Andy A Cole
- Laboratory of Neurobiology, National Institute of Neurological Disorders and Strokes, National Institutes of Health Bethesda, MD, USA ; Department of Cell and Molecular Biology, Northwestern University Chicago, IL, USA
| | - Xiaobing Chen
- Laboratory of Neurobiology, National Institute of Neurological Disorders and Strokes, National Institutes of Health Bethesda, MD, USA
| | - Thomas S Reese
- Laboratory of Neurobiology, National Institute of Neurological Disorders and Strokes, National Institutes of Health Bethesda, MD, USA
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Castañeda P, Muñoz M, García-Rojo G, Ulloa JL, Bravo JA, Márquez R, García-Pérez MA, Arancibia D, Araneda K, Rojas PS, Mondaca-Ruff D, Díaz-Véliz G, Mora S, Aliaga E, Fiedler JL. Association of N-cadherin levels and downstream effectors of Rho GTPases with dendritic spine loss induced by chronic stress in rat hippocampal neurons. J Neurosci Res 2015; 93:1476-91. [PMID: 26010004 DOI: 10.1002/jnr.23602] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Revised: 05/03/2015] [Accepted: 05/04/2015] [Indexed: 12/24/2022]
Abstract
Chronic stress promotes cognitive impairment and dendritic spine loss in hippocampal neurons. In this animal model of depression, spine loss probably involves a weakening of the interaction between pre- and postsynaptic cell adhesion molecules, such as N-cadherin, followed by disruption of the cytoskeleton. N-cadherin, in concert with catenin, stabilizes the cytoskeleton through Rho-family GTPases. Via their effector LIM kinase (LIMK), RhoA and ras-related C3 botulinum toxin substrate 1 (RAC) GTPases phosphorylate and inhibit cofilin, an actin-depolymerizing molecule, favoring spine growth. Additionally, RhoA, through Rho kinase (ROCK), inactivates myosin phosphatase through phosphorylation of the myosin-binding subunit (MYPT1), producing actomyosin contraction and probable spine loss. Some micro-RNAs negatively control the translation of specific mRNAs involved in Rho GTPase signaling. For example, miR-138 indirectly activates RhoA, and miR-134 reduces LIMK1 levels, resulting in spine shrinkage; in contrast, miR-132 activates RAC1, promoting spine formation. We evaluated whether N-cadherin/β-catenin and Rho signaling is sensitive to chronic restraint stress. Stressed rats exhibit anhedonia, impaired associative learning, and immobility in the forced swim test and reduction in N-cadherin levels but not β-catenin in the hippocampus. We observed a reduction in spine number in the apical dendrites of CA1 pyramidal neurons, with no effect on the levels of miR-132 or miR-134. Although the stress did not modify the RAC-LIMK-cofilin signaling pathway, we observed increased phospho-MYPT1 levels, probably mediated by RhoA-ROCK activation. Furthermore, chronic stress raises the levels of miR-138 in accordance with the observed activation of the RhoA-ROCK pathway. Our findings suggest that a dysregulation of RhoA-ROCK activity by chronic stress could potentially underlie spine loss in hippocampal neurons.
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Affiliation(s)
- Patricia Castañeda
- Department of Biology, Faculty of Sciences, Universidad Metropolitana de Ciencias de la Educación, Santiago, Chile
| | - Mauricio Muñoz
- Laboratory of Neuroplasticity and Neurogenetics, Department of Biochemistry and Molecular Biology, Faculty of Chemistry and Pharmaceutical Sciences, Universidad de Chile, Santiago, Chile
| | - Gonzalo García-Rojo
- Laboratory of Neuroplasticity and Neurogenetics, Department of Biochemistry and Molecular Biology, Faculty of Chemistry and Pharmaceutical Sciences, Universidad de Chile, Santiago, Chile
| | - José L Ulloa
- Laboratory of Neuroplasticity and Neurogenetics, Department of Biochemistry and Molecular Biology, Faculty of Chemistry and Pharmaceutical Sciences, Universidad de Chile, Santiago, Chile
| | - Javier A Bravo
- Grupo de NeuroGastroBioquímica, Laboratorio de Química Biológica, Instituto de Química, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| | - Ruth Márquez
- Laboratory of Neuroplasticity and Neurogenetics, Department of Biochemistry and Molecular Biology, Faculty of Chemistry and Pharmaceutical Sciences, Universidad de Chile, Santiago, Chile
| | - M Alexandra García-Pérez
- Laboratory of Neuroplasticity and Neurogenetics, Department of Biochemistry and Molecular Biology, Faculty of Chemistry and Pharmaceutical Sciences, Universidad de Chile, Santiago, Chile
| | - Damaris Arancibia
- Laboratory of Neuroplasticity and Neurogenetics, Department of Biochemistry and Molecular Biology, Faculty of Chemistry and Pharmaceutical Sciences, Universidad de Chile, Santiago, Chile
| | - Karina Araneda
- Laboratory of Neuroplasticity and Neurogenetics, Department of Biochemistry and Molecular Biology, Faculty of Chemistry and Pharmaceutical Sciences, Universidad de Chile, Santiago, Chile
| | - Paulina S Rojas
- Laboratory of Neuroplasticity and Neurogenetics, Department of Biochemistry and Molecular Biology, Faculty of Chemistry and Pharmaceutical Sciences, Universidad de Chile, Santiago, Chile
| | - David Mondaca-Ruff
- Graduate Student PhD Program, Department of Pharmacology, Faculty of Chemistry and Pharmaceutical Sciences, Universidad de Chile, Santiago, Chile
| | - Gabriela Díaz-Véliz
- Laboratorio Farmacología del Comportamiento, ICBM, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Sergio Mora
- Laboratorio Farmacología del Comportamiento, ICBM, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Esteban Aliaga
- Escuela de Kinesiología, Facultad de Ciencias, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| | - Jenny L Fiedler
- Laboratory of Neuroplasticity and Neurogenetics, Department of Biochemistry and Molecular Biology, Faculty of Chemistry and Pharmaceutical Sciences, Universidad de Chile, Santiago, Chile
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Hippocampal Pruning as a New Theory of Schizophrenia Etiopathogenesis. Mol Neurobiol 2015; 53:2065-2081. [PMID: 25902861 DOI: 10.1007/s12035-015-9174-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2014] [Accepted: 04/13/2015] [Indexed: 12/20/2022]
Abstract
Pruning in neurons has been suggested to be strongly involved in Schizophrenia's (SKZ) etiopathogenesis in recent biological, imaging, and genetic studies. We investigated the impact of protein-coding genes known to be involved in pruning, collected by a systematic literature research, in shaping the risk for SKZ in a case-control sample of 9,490 subjects (Psychiatric Genomics Consortium). Moreover, their modifications through evolution (humans, chimpanzees, and rats) and subcellular localization (as indicative of their biological function) were also investigated. We also performed a biological pathways (Gene Ontology) analysis. Genetics analyses found four genes (DLG1, NOS1, THBS4, and FADS1) and 17 pathways strongly involved in pruning and SKZ in previous literature findings to be significantly associated with the sample under analysis. The analysis of the subcellular localization found that secreted genes, and so regulatory ones, are the least conserved through evolution and also the most associated with SKZ. Their cell line and regional brain expression analysis found that their areas of primary expression are neuropil and the hippocampus, respectively. At the best of our knowledge, for the first time, we were able to describe the SKZ neurodevelopmental hypothesis starting from a single biological process. We can also hypothesize how alterations in pruning fine regulation and orchestration, strongly related with the evolutionary newest (and so more sensitive) secreted proteins, may be of particular relevance in the hippocampus. This early alteration may lead to a mis-structuration of neural connectivity, resulting in the different brain alteration that characterizes SKZ patients.
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Abstract
During brain development, billions of neurons organize into highly specific circuits. To form specific circuits, neurons must build the appropriate types of synapses with appropriate types of synaptic partners while avoiding incorrect partners in a dense cellular environment. Defining the cellular and molecular rules that govern specific circuit formation has significant scientific and clinical relevance because fine scale connectivity defects are thought to underlie many cognitive and psychiatric disorders. Organizing specific neural circuits is an enormously complicated developmental process that requires the concerted action of many molecules, neural activity, and temporal events. This review focuses on one class of molecules postulated to play an important role in target selection and specific synapse formation: the classic cadherins. Cadherins have a well-established role in epithelial cell adhesion, and although it has long been appreciated that most cadherins are expressed in the brain, their role in synaptic specificity is just beginning to be unraveled. Here, we review past and present studies implicating cadherins as active participants in the formation, function, and dysfunction of specific neural circuits and pose some of the major remaining questions.
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Affiliation(s)
- Raunak Basu
- a Department of Neurobiology and Anatomy ; University of Utah ; Salt Lake City , UT USA
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Friedman LG, Benson DL, Huntley GW. Cadherin-based transsynaptic networks in establishing and modifying neural connectivity. Curr Top Dev Biol 2015; 112:415-65. [PMID: 25733148 DOI: 10.1016/bs.ctdb.2014.11.025] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
It is tacitly understood that cell adhesion molecules (CAMs) are critically important for the development of cells, circuits, and synapses in the brain. What is less clear is what CAMs continue to contribute to brain structure and function after the early period of development. Here, we focus on the cadherin family of CAMs to first briefly recap their multidimensional roles in neural development and then to highlight emerging data showing that with maturity, cadherins become largely dispensible for maintaining neuronal and synaptic structure, instead displaying new and narrower roles at mature synapses where they critically regulate dynamic aspects of synaptic signaling, structural plasticity, and cognitive function. At mature synapses, cadherins are an integral component of multiprotein networks, modifying synaptic signaling, morphology, and plasticity through collaborative interactions with other CAM family members as well as a variety of neurotransmitter receptors, scaffolding proteins, and other effector molecules. Such recognition of the ever-evolving functions of synaptic cadherins may yield insight into the pathophysiology of brain disorders in which cadherins have been implicated and that manifest at different times of life.
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Affiliation(s)
- Lauren G Friedman
- Fishberg Department of Neuroscience, Friedman Brain Institute and the Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, USA
| | - Deanna L Benson
- Fishberg Department of Neuroscience, Friedman Brain Institute and the Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, USA
| | - George W Huntley
- Fishberg Department of Neuroscience, Friedman Brain Institute and the Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, USA.
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Friedman LG, Riemslagh FW, Sullivan JM, Mesias R, Williams FM, Huntley GW, Benson DL. Cadherin-8 expression, synaptic localization, and molecular control of neuronal form in prefrontal corticostriatal circuits. J Comp Neurol 2014; 523:75-92. [PMID: 25158904 DOI: 10.1002/cne.23666] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2014] [Revised: 08/25/2014] [Accepted: 08/25/2014] [Indexed: 02/02/2023]
Abstract
Neocortical interactions with the dorsal striatum support many motor and executive functions, and such underlying functional networks are particularly vulnerable to a variety of developmental, neurological, and psychiatric brain disorders, including autism spectrum disorders, Parkinson's disease, and Huntington's disease. Relatively little is known about the development of functional corticostriatal interactions, and in particular, virtually nothing is known of the molecular mechanisms that control generation of prefrontal cortex-striatal circuits. Here, we used regional and cellular in situ hybridization techniques coupled with neuronal tract tracing to show that Cadherin-8 (Cdh8), a homophilic adhesion protein encoded by a gene associated with autism spectrum disorders and learning disability susceptibility, is enriched within striatal projection neurons in the medial prefrontal cortex and in striatal medium spiny neurons forming the direct or indirect pathways. Developmental analysis of quantitative real-time polymerase chain reaction and western blot data show that Cdh8 expression peaks in the prefrontal cortex and striatum at P10, when cortical projections start to form synapses in the striatum. High-resolution immunoelectron microscopy shows that Cdh8 is concentrated at excitatory synapses in the dorsal striatum, and Cdh8 knockdown in cortical neurons impairs dendritic arborization and dendrite self-avoidance. Taken together, our findings indicate that Cdh8 delineates developing corticostriatal circuits where it is a strong candidate for regulating the generation of normal cortical projections, neuronal morphology, and corticostriatal synapses.
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Affiliation(s)
- Lauren G Friedman
- Fishberg Department of Neuroscience, Friedman Brain Institute and The Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, 10029
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Nikitczuk JS, Patil SB, Matikainen-Ankney BA, Scarpa J, Shapiro ML, Benson DL, Huntley GW. N-cadherin regulates molecular organization of excitatory and inhibitory synaptic circuits in adult hippocampus in vivo. Hippocampus 2014; 24:943-962. [PMID: 24753442 DOI: 10.1002/hipo.22282] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2014] [Accepted: 04/09/2014] [Indexed: 12/31/2022]
Abstract
N-Cadherin and β-catenin form a transsynaptic adhesion complex required for spine and synapse development. In adulthood, N-cadherin mediates persistent synaptic plasticity, but whether the role of N-cadherin at mature synapses is similar to that at developing synapses is unclear. To address this, we conditionally ablated N-cadherin from excitatory forebrain synapses in mice starting in late postnatal life and examined hippocampal structure and function in adulthood. In the absence of N-cadherin, β-catenin levels were reduced, but numbers of excitatory synapses were unchanged, and there was no impact on number or shape of dendrites or spines. However, the composition of synaptic molecules was altered. Levels of GluA1 and its scaffolding protein PSD95 were diminished and the density of immunolabeled puncta was decreased, without effects on other glutamate receptors and their scaffolding proteins. Additionally, loss of N-cadherin at excitatory synapses triggered increases in the density of markers for inhibitory synapses and decreased severity of hippocampal seizures. Finally, adult mutant mice were profoundly impaired in hippocampal-dependent memory for spatial episodes. These results demonstrate a novel function for the N-cadherin/β-catenin complex in regulating ionotropic receptor composition of excitatory synapses, an appropriate balance of excitatory and inhibitory synaptic proteins and the maintenance of neural circuitry necessary to generate flexible yet persistent cognitive and synaptic function.
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Affiliation(s)
- Jessica S Nikitczuk
- Fishberg Department of Neuroscience, Friedman Brain Institute and The Graduate School of Biomedical Sciences, The Icahn School of Medicine at Mount Sinai, 1470 Madison Avenue, New York, NY 10029
| | - Shekhar B Patil
- Fishberg Department of Neuroscience, Friedman Brain Institute and The Graduate School of Biomedical Sciences, The Icahn School of Medicine at Mount Sinai, 1470 Madison Avenue, New York, NY 10029
| | - Bridget A Matikainen-Ankney
- Fishberg Department of Neuroscience, Friedman Brain Institute and The Graduate School of Biomedical Sciences, The Icahn School of Medicine at Mount Sinai, 1470 Madison Avenue, New York, NY 10029
| | - Joseph Scarpa
- Fishberg Department of Neuroscience, Friedman Brain Institute and The Graduate School of Biomedical Sciences, The Icahn School of Medicine at Mount Sinai, 1470 Madison Avenue, New York, NY 10029
| | - Matthew L Shapiro
- Fishberg Department of Neuroscience, Friedman Brain Institute and The Graduate School of Biomedical Sciences, The Icahn School of Medicine at Mount Sinai, 1470 Madison Avenue, New York, NY 10029
| | - Deanna L Benson
- Fishberg Department of Neuroscience, Friedman Brain Institute and The Graduate School of Biomedical Sciences, The Icahn School of Medicine at Mount Sinai, 1470 Madison Avenue, New York, NY 10029
| | - George W Huntley
- Fishberg Department of Neuroscience, Friedman Brain Institute and The Graduate School of Biomedical Sciences, The Icahn School of Medicine at Mount Sinai, 1470 Madison Avenue, New York, NY 10029
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Yang X, Hou D, Jiang W, Zhang C. Intercellular protein-protein interactions at synapses. Protein Cell 2014; 5:420-44. [PMID: 24756565 PMCID: PMC4026422 DOI: 10.1007/s13238-014-0054-z] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2014] [Accepted: 03/23/2014] [Indexed: 12/11/2022] Open
Abstract
Chemical synapses are asymmetric intercellular junctions through which neurons send nerve impulses to communicate with other neurons or excitable cells. The appropriate formation of synapses, both spatially and temporally, is essential for brain function and depends on the intercellular protein-protein interactions of cell adhesion molecules (CAMs) at synaptic clefts. The CAM proteins link pre- and post-synaptic sites, and play essential roles in promoting synapse formation and maturation, maintaining synapse number and type, accumulating neurotransmitter receptors and ion channels, controlling neuronal differentiation, and even regulating synaptic plasticity directly. Alteration of the interactions of CAMs leads to structural and functional impairments, which results in many neurological disorders, such as autism, Alzheimer's disease and schizophrenia. Therefore, it is crucial to understand the functions of CAMs during development and in the mature neural system, as well as in the pathogenesis of some neurological disorders. Here, we review the function of the major classes of CAMs, and how dysfunction of CAMs relates to several neurological disorders.
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Affiliation(s)
- Xiaofei Yang
- Key Laboratory of Cognitive Science, Laboratory of Membrane Ion Channels and Medicine, College of Biomedical Engineering, South-Central University for Nationalities, Wuhan, 430074 China
| | - Dongmei Hou
- Key Laboratory of Cognitive Science, Laboratory of Membrane Ion Channels and Medicine, College of Biomedical Engineering, South-Central University for Nationalities, Wuhan, 430074 China
- State Key Laboratory of Biomembrane and Membrane Biotechnology, College of Life Sciences, Peking University, Beijing, 100871 China
- PKU-IDG/McGovern Institute for Brain Research, Peking University, Beijing, 100871 China
| | - Wei Jiang
- Key Laboratory of Cognitive Science, Laboratory of Membrane Ion Channels and Medicine, College of Biomedical Engineering, South-Central University for Nationalities, Wuhan, 430074 China
- State Key Laboratory of Biomembrane and Membrane Biotechnology, College of Life Sciences, Peking University, Beijing, 100871 China
- PKU-IDG/McGovern Institute for Brain Research, Peking University, Beijing, 100871 China
| | - Chen Zhang
- State Key Laboratory of Biomembrane and Membrane Biotechnology, College of Life Sciences, Peking University, Beijing, 100871 China
- PKU-IDG/McGovern Institute for Brain Research, Peking University, Beijing, 100871 China
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Yam PT, Pincus Z, Gupta GD, Bashkurov M, Charron F, Pelletier L, Colman DR. N-cadherin relocalizes from the periphery to the center of the synapse after transient synaptic stimulation in hippocampal neurons. PLoS One 2013; 8:e79679. [PMID: 24223993 PMCID: PMC3815108 DOI: 10.1371/journal.pone.0079679] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2013] [Accepted: 09/23/2013] [Indexed: 11/19/2022] Open
Abstract
N-cadherin is a cell adhesion molecule which is enriched at synapses. Binding of N-cadherin molecules to each other across the synaptic cleft has been postulated to stabilize adhesion between the presynaptic bouton and the postsynaptic terminal. N-cadherin is also required for activity-induced changes at synapses, including hippocampal long term potentiation and activity-induced spine expansion and stabilization. We hypothesized that these activity-dependent changes might involve changes in N-cadherin localization within synapses. To determine whether synaptic activity changes the localization of N-cadherin, we used structured illumination microscopy, a super-resolution approach which overcomes the conventional resolution limits of light microscopy, to visualize the localization of N-cadherin within synapses of hippocampal neurons. We found that synaptic N-cadherin exhibits a spectrum of localization patterns, ranging from puncta at the periphery of the synapse adjacent to the active zone to an even distribution along the synaptic cleft. Furthermore, the N-cadherin localization pattern within synapses changes during KCl depolarization and after transient synaptic stimulation. During KCl depolarization, N-cadherin relocalizes away from the central region of the synaptic cleft to the periphery of the synapse. In contrast, after transient synaptic stimulation with KCl followed by a period of rest in normal media, fewer synapses have N-cadherin present as puncta at the periphery and more synapses have N-cadherin present more centrally and uniformly along the synapse compared to unstimulated cells. This indicates that transient synaptic stimulation modulates N-cadherin localization within the synapse. These results bring new information to the structural organization and activity-induced changes occurring at synapses, and suggest that N-cadherin relocalization may contribute to activity dependent changes at synapses.
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Affiliation(s)
- Patricia T. Yam
- Department of Neurology and Neurosurgery, Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada
- Program in Neuroengineering, McGill University, Montreal, Quebec, Canada
- * E-mail:
| | - Zachary Pincus
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, Connecticut, United States of America
| | - Gagan D. Gupta
- Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada
| | - Mikhail Bashkurov
- Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada
| | - Frédéric Charron
- Program in Neuroengineering, McGill University, Montreal, Quebec, Canada
- Molecular Biology of Neural Development, Institut de Recherches Cliniques de Montréal (IRCM), Montreal, Quebec, Canada
- Department of Medicine, University of Montreal, Montreal, Quebec, Canada
- Department of Anatomy and Cell Biology, Department of Biology, Division of Experimental Medicine, McGill University, Montreal, Quebec, Canada
| | - Laurence Pelletier
- Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - David R. Colman
- Department of Neurology and Neurosurgery, Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada
- Program in Neuroengineering, McGill University, Montreal, Quebec, Canada
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Chugh D, Nilsson P, Afjei SA, Bakochi A, Ekdahl CT. Brain inflammation induces post-synaptic changes during early synapse formation in adult-born hippocampal neurons. Exp Neurol 2013; 250:176-88. [PMID: 24047952 DOI: 10.1016/j.expneurol.2013.09.005] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2013] [Revised: 08/16/2013] [Accepted: 09/09/2013] [Indexed: 10/26/2022]
Abstract
An inflammatory reaction in the brain is primarily characterized by activation of parenchymal microglial cells. Microglia regulate several aspects of adult neurogenesis, i.e. the continuous production of new neurons in the adult brain. Hippocampal neurogenesis is thought to be important for memory formation, but its role in brain diseases is not clear. We have previously shown that brain inflammation modulates the functional integration of newly formed hippocampal neurons. Here, we explored whether there is a defined time period during synaptic development when new neurons are susceptible to brain inflammation. Newly formed hippocampal neurons, born in an intact environment in the adult mouse brain, were exposed to lipopolysaccharide (LPS)-induced inflammation during either early or late phases of excitatory and inhibitory synaptogenesis. We used intra-hippocampal injections of GFP-retroviral vector (RV-GFP) to label the new neurons and ipsilateral LPS injection at either 1 or 4weeks post-RV-GFP injection. A single intra-hippocampal LPS injection induced an inflammatory response for at least 3weeks, including an acute transient pro-inflammatory cytokine release as well as a sub-acute and sustained change in microglial morphology. The general cytoarchitecture of the hippocampal dentate gyrus, including granule cell layer (GCL) volume, and astrocytic glial fibrillary acidic protein expression was not different compared to vehicle controls, and no Fluoro-Jade-positive cell death was observed. New neurons encountering this inflammatory environment exhibited no changes in their gross morphology. However, when inflammation occurred during early stages of synapse formation, we found a region-specific increase in the number of thin dendritic spines and post-synaptic density-95 (PSD-95) cluster formation on spines, suggesting an enhanced excitatory synaptic connectivity in the newborn neurons. No changes were observed in the expression of N-cadherin, an adhesion molecule primarily associated with excitatory synapses. At the inhibitory synapses, alterations due to inflammation were also evident during early but not later stages of synaptic development. Gephyrin, an inhibitory scaffolding protein, was down-regulated in the somatic region, while the adhesion molecules neuroligin-2 (NL-2) and neurofascin were increased in the somatic region and/or on the dendrites. The GABAA receptor-α2 subunit (GABAAR-α2) was increased, while pre/peri-synaptic GABA clustering remained unaltered. The disproportional changes in post-synaptic adhesion molecules and GABAA receptor compared to scaffolding protein expression at the inhibitory synapses during brain inflammation are likely to cause an imbalance in GABAergic transmission. These changes were specific for the newborn neurons and were not observed when estimating the overall expression of gephyrin, NL-2, and GABAAR-α2 in the hippocampal GCL. The expression of interleukin-1-type 1 receptor (IL-1R1) on preferentially the somatic region of new neurons, often in close apposition to NL-2 clusters, may indicate a direct interaction between brain inflammation and synaptic proteins on newborn neurons. In summary, this study provides evidence that adult-born hippocampal neurons alter their inhibitory and excitatory synaptic integration when encountering an LPS-induced brain inflammation during the initial stages of synapse formation. Changes at this critical developmental period are likely to interfere with the physiological functions of new neurons within the hippocampus.
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Affiliation(s)
- Deepti Chugh
- Inflammation and Stem Cell Therapy Group, Wallenberg Neuroscience Center, Division of Clinical Neurophysiology, Lund University, SE-221 84 Lund, Sweden; Epilepsy Center, Department of Clinical Sciences, Lund University, SE-221 84 Lund, Sweden
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50
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Togashi H. [The role of cell adhesion molecules in neurite recognition and synaptogenesis of the mammalian nervous system]. Nihon Yakurigaku Zasshi 2013; 142:100-5. [PMID: 24025489 DOI: 10.1254/fpj.142.100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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