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Yeo XY, Tam D, Jo Y, Kim JE, Ryu D, Chan JP, Jung S. Polar Lipids Supplementation Enhances Basal Excitatory Synaptic Transmission in Primary Cortical Neuron. Mol Nutr Food Res 2024:e2300883. [PMID: 38984736 DOI: 10.1002/mnfr.202300883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Revised: 05/28/2024] [Indexed: 07/11/2024]
Abstract
SCOPE Polar lipids, such as gangliosides and phospholipids, are fundamental structural components that play critical roles in the development and maturation of neurons in the brain. Recent evidence has demonstrated that dietary intakes of polar lipids in early life are associated with improved cognitive outcomes during infancy and adolescence. However, the specific mechanisms through which these lipids impact cognition remain unclear. METHODS AND RESULTS This study examines the direct physiological impact of polar lipid supplementation, in the form of buttermilk powder, on primary cortical neuron growth and maturation. The changes are measured with postsynaptic current response recordings, immunohistochemical examination of functional synapse localization and numbers, and the biochemical quantification of receptors responsible for neuronal synaptic neurotransmission. Chronic exposure to polar lipids increases primary mouse cortical neuron basal excitatory synapse response strength attributed to enhanced dendritic complexity and an altered expression of the excitatory α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor subunit 2 (GluR2). CONCLUSION The present finding suggests that dietary polar lipids improve human cognition through an enhancement of neuronal maturation and/or function.
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Affiliation(s)
- Xin Yi Yeo
- Institute of Molecular and Cell Biology, Agency for Science, Technology and Research, 61 Biopolis Drive, Proteos, Singapore, 138673, Republic of Singapore
- Department of Psychological Medicine, Yong Loo Lin School of Medicine, National University of Singapore, 1E Kent Ridge Road, NUHS Tower Block, Level 9, Singapore, 119228, Republic of Singapore
| | - Dao Tam
- Department of Molecular Cell Biology, Sungkyunkwan University School of Medicine (SKKU), 2066 Seobu-ro, Jangan-gu, Suwon, Gyeonggi-do, 16419, Republic of Korea
| | - Yunju Jo
- Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology, 123 Cheomdangwagi-ro, Buk-gu, Gwangju, 61005, Republic of Korea
| | - Jung Eun Kim
- Department of Food Science & Technology, Faculty of Science, National University of Singapore, S14 Level 6, Science Drive 2, Singapore, 117542, Republic of Singapore
| | - Dongryeol Ryu
- Department of Molecular Cell Biology, Sungkyunkwan University School of Medicine (SKKU), 2066 Seobu-ro, Jangan-gu, Suwon, Gyeonggi-do, 16419, Republic of Korea
- Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology, 123 Cheomdangwagi-ro, Buk-gu, Gwangju, 61005, Republic of Korea
| | - Jia Pei Chan
- Research and Development Department, Abbott Nutrition, 3300 Stelzer Road, RP3-2, Columbus, Ohio, 43219, USA
| | - Sangyong Jung
- Institute of Molecular and Cell Biology, Agency for Science, Technology and Research, 61 Biopolis Drive, Proteos, Singapore, 138673, Republic of Singapore
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, 2 Medical Drive, MD9, Singapore, 117593, Republic of Singapore
- Department of Medical Science, College of Medicine, CHA University, CHA Bio Complex, 335 Pangyo-ro, Bundang-gu, Seongnam, Gyeonggi-do, 13488, Republic of Korea
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2
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Park SJ, An SY, An YJ, Kim KS, Kim H, Cho JH, Lee YC. Promotion of neurite outgrowth by 3,5,7,3',4'-pentamethoxyflavone is mediated through ERK signaling pathway in Neuro2a cells. J Nat Med 2024; 78:599-607. [PMID: 38662302 DOI: 10.1007/s11418-024-01809-y] [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: 10/26/2023] [Accepted: 03/26/2024] [Indexed: 04/26/2024]
Abstract
In this study, the effects of 3,5,7,3',4'-pentamethoxyflavone (KP1), a major bioactive ingredient isolated from the Kaempferia parviflora rhizomes, on a neurite outgrowth in Neuro2a cells and its mechanism have been investigated. KP1 increased concentration-dependently the percentage of neurite-bearing cells. KP1 showed a remarkable capability to elicit neurite outgrowth in Neuro2a cells, as evidenced by morphological alterations and immunostaining using anti-class III β-tubulin and anti-NeuN antibodies. KP1 also displayed a higher neurogenic activity than retinoic acid (RA), a promoter of neurite outgrowth in Neuro2a cells. KP1 treatment caused significant elevation in phosphorylation of extracellular signal-regulated kinase (ERK), p38 mitogen-activated protein kinase (p38 MAPK) and glycogen synthase kinase-3β (GSK-3β). However, KP1-triggered neurite outgrowth was markedly inhibited by treatment with the ERK inhibitor U0126, whereas p38 MAPK inhibitor SB203580 and GSK-3β inhibitor SB216763 did not influence KP1-induced neurite outgrowth. These results demonstrate that KP1 elicits neurite outgrowth and triggers cell differentiation of Neuro2a cells through ERK signal pathway.
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Affiliation(s)
- Shin-Ji Park
- Department of Medicinal Biotechnology, College of Health Sciences, Dong-A University, Busan, 604-714, South Korea
| | - So-Young An
- Department of Medicinal Biotechnology, College of Health Sciences, Dong-A University, Busan, 604-714, South Korea
| | - Yeon Jin An
- Department of Medicinal Biotechnology, College of Health Sciences, Dong-A University, Busan, 604-714, South Korea
| | - Kyoung-Sook Kim
- Department of Medicinal Biotechnology, College of Health Sciences, Dong-A University, Busan, 604-714, South Korea
| | - Hyunju Kim
- Department of Medicinal Biotechnology, College of Health Sciences, Dong-A University, Busan, 604-714, South Korea
| | - Jong Hyun Cho
- Department of Medicinal Biotechnology, College of Health Sciences, Dong-A University, Busan, 604-714, South Korea.
| | - Young-Choon Lee
- Department of Medicinal Biotechnology, College of Health Sciences, Dong-A University, Busan, 604-714, South Korea.
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3
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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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4
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Paşcalău R, Badea TC. Signaling - transcription interactions in mouse retinal ganglion cells early axon pathfinding -a literature review. FRONTIERS IN OPHTHALMOLOGY 2023; 3:1180142. [PMID: 38983012 PMCID: PMC11182120 DOI: 10.3389/fopht.2023.1180142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/05/2023] [Accepted: 04/21/2023] [Indexed: 07/11/2024]
Abstract
Sending an axon out of the eye and into the target brain nuclei is the defining feature of retinal ganglion cells (RGCs). The literature on RGC axon pathfinding is vast, but it focuses mostly on decision making events such as midline crossing at the optic chiasm or retinotopic mapping at the target nuclei. In comparison, the exit of RGC axons out of the eye is much less explored. The first checkpoint on the RGC axons' path is the optic cup - optic stalk junction (OC-OS). OC-OS development and the exit of the RGC pioneer axons out of the eye are coordinated spatially and temporally. By the time the optic nerve head domain is specified, the optic fissure margins are in contact and the fusion process is ongoing, the first RGCs are born in its proximity and send pioneer axons in the optic stalk. RGC differentiation continues in centrifugal waves. Later born RGC axons fasciculate with the more mature axons. Growth cones at the end of the axons respond to guidance cues to adopt a centripetal direction, maintain nerve fiber layer restriction and to leave the optic cup. Although there is extensive information on OC-OS development, we still have important unanswered questions regarding its contribution to the exit of the RGC axons out of the eye. We are still to distinguish the morphogens of the OC-OS from the axon guidance molecules which are expressed in the same place at the same time. The early RGC transcription programs responsible for axon emergence and pathfinding are also unknown. This review summarizes the molecular mechanisms for early RGC axon guidance by contextualizing mouse knock-out studies on OC-OS development with the recent transcriptomic studies on developing RGCs in an attempt to contribute to the understanding of human optic nerve developmental anomalies. The published data summarized here suggests that the developing optic nerve head provides a physical channel (the closing optic fissure) as well as molecular guidance cues for the pioneer RGC axons to exit the eye.
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Affiliation(s)
- Raluca Paşcalău
- Research and Development Institute, Transilvania University of Braşov, Braşov, Romania
- Ophthalmology Clinic, Cluj County Emergency Hospital, Cluj-Napoca, Romania
| | - Tudor Constantin Badea
- Research and Development Institute, Transilvania University of Braşov, Braşov, Romania
- National Center for Brain Research, Institutul de Cercetări pentru Inteligență Artificială, Romanian Academy, Bucharest, Romania
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5
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Zeng CW. Multipotent Mesenchymal Stem Cell-Based Therapies for Spinal Cord Injury: Current Progress and Future Prospects. BIOLOGY 2023; 12:biology12050653. [PMID: 37237467 DOI: 10.3390/biology12050653] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 04/25/2023] [Accepted: 04/25/2023] [Indexed: 05/28/2023]
Abstract
Spinal cord injury (SCI) represents a significant medical challenge, often resulting in permanent disability and severely impacting the quality of life for affected individuals. Traditional treatment options remain limited, underscoring the need for novel therapeutic approaches. In recent years, multipotent mesenchymal stem cells (MSCs) have emerged as a promising candidate for SCI treatment due to their multifaceted regenerative capabilities. This comprehensive review synthesizes the current understanding of the molecular mechanisms underlying MSC-mediated tissue repair in SCI. Key mechanisms discussed include neuroprotection through the secretion of growth factors and cytokines, promotion of neuronal regeneration via MSC differentiation into neural cell types, angiogenesis through the release of pro-angiogenic factors, immunomodulation by modulating immune cell activity, axonal regeneration driven by neurotrophic factors, and glial scar reduction via modulation of extracellular matrix components. Additionally, the review examines the various clinical applications of MSCs in SCI treatment, such as direct cell transplantation into the injured spinal cord, tissue engineering using biomaterial scaffolds that support MSC survival and integration, and innovative cell-based therapies like MSC-derived exosomes, which possess regenerative and neuroprotective properties. As the field progresses, it is crucial to address the challenges associated with MSC-based therapies, including determining optimal sources, intervention timing, and delivery methods, as well as developing standardized protocols for MSC isolation, expansion, and characterization. Overcoming these challenges will facilitate the translation of preclinical findings into clinical practice, providing new hope and improved treatment options for individuals living with the devastating consequences of SCI.
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Affiliation(s)
- Chih-Wei Zeng
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
- Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
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6
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Li VJ, Chorghay Z, Ruthazer ES. A Guide for the Multiplexed: The Development of Visual Feature Maps in the Brain. Neuroscience 2023; 508:62-75. [PMID: 35952996 DOI: 10.1016/j.neuroscience.2022.07.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Revised: 07/21/2022] [Accepted: 07/27/2022] [Indexed: 01/17/2023]
Abstract
Neural maps are found ubiquitously in the brain, where they encode a wide range of behaviourally relevant features into neural space. Developmental studies have shown that animals devote a great deal of resources to establish consistently patterned organization in neural circuits throughout the nervous system, but what purposes maps serve beneath their often intricate appearance and composition is a topic of active debate and exploration. In this article, we review the general mechanisms of map formation, with a focus on the visual system, and then survey notable organizational properties of neural maps: the multiplexing of feature representations through a nested architecture, the interspersing of fine-scale heterogeneity within a globally smooth organization, and the complex integration at the microcircuit level that enables a high dimensionality of information encoding. Finally, we discuss the roles of maps in cortical functions, including input segregation, feature extraction and routing of circuit outputs for higher order processing, as well as the evolutionary basis for the properties we observe in neural maps.
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Affiliation(s)
- Vanessa J Li
- Montreal Neurological Institute-Hospital, McGill University, 3801 University St. Montreal, Quebec H3A 2B4, Canada
| | - Zahraa Chorghay
- Montreal Neurological Institute-Hospital, McGill University, 3801 University St. Montreal, Quebec H3A 2B4, Canada
| | - Edward S Ruthazer
- Montreal Neurological Institute-Hospital, McGill University, 3801 University St. Montreal, Quebec H3A 2B4, Canada
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7
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Santos FM, Ciordia S, Mesquita J, Cruz C, Sousa JPCE, Passarinha LA, Tomaz CT, Paradela A. Proteomics profiling of vitreous humor reveals complement and coagulation components, adhesion factors, and neurodegeneration markers as discriminatory biomarkers of vitreoretinal eye diseases. Front Immunol 2023; 14:1107295. [PMID: 36875133 PMCID: PMC9978817 DOI: 10.3389/fimmu.2023.1107295] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Accepted: 02/01/2023] [Indexed: 02/18/2023] Open
Abstract
Introduction Diabetic retinopathy (DR) and age-related macular degeneration (AMD) are leading causes of visual impairment and blindness in people aged 50 years or older in middle-income and industrialized countries. Anti-VEGF therapies have improved the management of neovascular AMD (nAMD) and proliferative DR (PDR), no treatment options exist for the highly prevalent dry form of AMD. Methods To unravel the biological processes underlying these pathologies and to find new potential biomarkers, a label-free quantitative (LFQ) method was applied to analyze the vitreous proteome in PDR (n=4), AMD (n=4) compared to idiopathic epiretinal membranes (ERM) (n=4). Results and discussion Post-hoc tests revealed 96 proteins capable of differentiating among the different groups, whereas 118 proteins were found differentially regulated in PDR compared to ERM and 95 proteins in PDR compared to dry AMD. Pathway analysis indicates that mediators of complement, coagulation cascades and acute phase responses are enriched in PDR vitreous, whilst proteins highly correlated to the extracellular matrix (ECM) organization, platelet degranulation, lysosomal degradation, cell adhesion, and central nervous system development were found underexpressed. According to these results, 35 proteins were selected and monitored by MRM (multiple reaction monitoring) in a larger cohort of patients with ERM (n=21), DR/PDR (n=20), AMD (n=11), and retinal detachment (n=13). Of these, 26 proteins could differentiate between these vitreoretinal diseases. Based on Partial least squares discriminant and multivariate exploratory receiver operating characteristic (ROC) analyses, a panel of 15 discriminatory biomarkers was defined, which includes complement and coagulation components (complement C2 and prothrombin), acute-phase mediators (alpha-1-antichymotrypsin), adhesion molecules (e.g., myocilin, galectin-3-binding protein), ECM components (opticin), and neurodegeneration biomarkers (beta-amyloid, amyloid-like protein 2).
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Affiliation(s)
- Fátima M Santos
- CICS-UBI - Health Sciences Research Centre, University of Beira Interior, Covilhã, Portugal.,Functional Proteomics Laboratory, Centro Nacional de Biotecnología, CSIC, Madrid, Spain
| | - Sergio Ciordia
- Functional Proteomics Laboratory, Centro Nacional de Biotecnología, CSIC, Madrid, Spain
| | - Joana Mesquita
- CICS-UBI - Health Sciences Research Centre, University of Beira Interior, Covilhã, Portugal
| | - Carla Cruz
- CICS-UBI - Health Sciences Research Centre, University of Beira Interior, Covilhã, Portugal.,Chemistry Department, Faculty of Sciences, University of Beira Interior, Covilhã, Portugal
| | - João Paulo Castro E Sousa
- CICS-UBI - Health Sciences Research Centre, University of Beira Interior, Covilhã, Portugal.,Department of Ophthalmology, Centro Hospitalar de Leiria, Leiria, Portugal
| | - Luís A Passarinha
- CICS-UBI - Health Sciences Research Centre, University of Beira Interior, Covilhã, Portugal.,Associate Laboratory i4HB - Institute for Health and Bioeconomy, Faculdade de Ciências e Tecnologia, Universidade NOVA, Caparica, Portugal.,UCIBIO-Applied Molecular Biosciences Unit, Departamento de Química/Departamento Ciências da Vida, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, Caparica, Portugal.,Laboratório de Fármaco-Toxicologia, UBIMedical, Universidade da Beira Interior, Covilhã, Portugal
| | - Cândida T Tomaz
- CICS-UBI - Health Sciences Research Centre, University of Beira Interior, Covilhã, Portugal.,Chemistry Department, Faculty of Sciences, University of Beira Interior, Covilhã, Portugal
| | - Alberto Paradela
- Functional Proteomics Laboratory, Centro Nacional de Biotecnología, CSIC, Madrid, Spain
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8
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Luo W, Cruz-Ochoa NA, Seng C, Egger M, Lukacsovich D, Lukacsovich T, Földy C. Pcdh11x controls target specification of mossy fiber sprouting. Front Neurosci 2022; 16:888362. [PMID: 36117624 PMCID: PMC9475199 DOI: 10.3389/fnins.2022.888362] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Accepted: 07/26/2022] [Indexed: 11/13/2022] Open
Abstract
Circuit formation is a defining characteristic of the developing brain. However, multiple lines of evidence suggest that circuit formation can also take place in adults, the mechanisms of which remain poorly understood. Here, we investigated the epilepsy-associated mossy fiber (MF) sprouting in the adult hippocampus and asked which cell surface molecules define its target specificity. Using single-cell RNAseq data, we found lack and expression of Pcdh11x in non-sprouting and sprouting neurons respectively. Subsequently, we used CRISPR/Cas9 genome editing to disrupt the Pcdh11x gene and characterized its consequences on sprouting. Although MF sprouting still developed, its target specificity was altered. New synapses were frequently formed on granule cell somata in addition to dendrites. Our findings shed light onto a key molecular determinant of target specificity in MF sprouting and contribute to understanding the molecular mechanism of adult brain rewiring.
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9
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Moreland T, Poulain FE. To Stick or Not to Stick: The Multiple Roles of Cell Adhesion Molecules in Neural Circuit Assembly. Front Neurosci 2022; 16:889155. [PMID: 35573298 PMCID: PMC9096351 DOI: 10.3389/fnins.2022.889155] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Accepted: 03/28/2022] [Indexed: 01/02/2023] Open
Abstract
Precise wiring of neural circuits is essential for brain connectivity and function. During development, axons respond to diverse cues present in the extracellular matrix or at the surface of other cells to navigate to specific targets, where they establish precise connections with post-synaptic partners. Cell adhesion molecules (CAMs) represent a large group of structurally diverse proteins well known to mediate adhesion for neural circuit assembly. Through their adhesive properties, CAMs act as major regulators of axon navigation, fasciculation, and synapse formation. While the adhesive functions of CAMs have been known for decades, more recent studies have unraveled essential, non-adhesive functions as well. CAMs notably act as guidance cues and modulate guidance signaling pathways for axon pathfinding, initiate contact-mediated repulsion for spatial organization of axonal arbors, and refine neuronal projections during circuit maturation. In this review, we summarize the classical adhesive functions of CAMs in axonal development and further discuss the increasing number of other non-adhesive functions CAMs play in neural circuit assembly.
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10
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Abstract
Neurexin-3 is primarily localized in the presynaptic membrane and forms complexes with various ligands located in the postsynaptic membrane. Neurexin-3 has important roles in synapse development and synapse functions. Neurexin-3 mediates excitatory presynaptic differentiation by interacting with leucine-rich-repeat transmembrane neuronal proteins. Meanwhile, neurexin-3 modulates the expression of presynaptic α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptors and γ-aminobutyric acid A receptors by interacting with neuroligins at excitatory and inhibitory synapses. Numerous studies have documented the potential contribution of neurexin-3 to neurodegenerative and neuropsychiatric disorders, such as Alzheimer's disease, addiction behaviors, and other diseases, which raises hopes that understanding the mechanisms of neurexin-3 may hold the key to developing new strategies for related illnesses. This review comprehensively covers the literature to provide current knowledge of the structure, function, and clinical role of neurexin-3.
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11
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Dromel PC, Singh D, Andres E, Likes M, Kurisawa M, Alexander-Katz A, Spector M, Young M. A bioinspired gelatin-hyaluronic acid-based hybrid interpenetrating network for the enhancement of retinal ganglion cells replacement therapy. NPJ Regen Med 2021; 6:85. [PMID: 34930951 PMCID: PMC8688498 DOI: 10.1038/s41536-021-00195-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Accepted: 10/20/2021] [Indexed: 11/25/2022] Open
Abstract
Biomaterial-based cell replacement approaches to regenerative medicine are emerging as promising treatments for a wide array of profound clinical problems. Here we report an interpenetrating polymer network (IPN) composed of gelatin-hydroxyphenyl propionic acid and hyaluronic acid tyramine that is able to enhance intravitreal retinal cell therapy. By tuning our bioinspired hydrogel to mimic the vitreous chemical composition and mechanical characteristics we were able to improve in vitro and in vivo viability of human retinal ganglion cells (hRGC) incorporated into the IPN. In vivo vitreal injections of cell-bearing IPN in rats showed extensive attachment to the inner limiting membrane of the retina, improving with hydrogels stiffness. Engrafted hRGC displayed signs of regenerating processes along the optic nerve. Of note was the decrease in the immune cell response to hRGC delivered in the gel. The findings compel further translation of the gelatin-hyaluronic acid IPN for intravitreal cell therapy.
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Affiliation(s)
- Pierre C Dromel
- Massachusetts Institute of Technology, Cambridge, MA, USA
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
| | - Deepti Singh
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
| | - Eliot Andres
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
| | | | - Motoichi Kurisawa
- A*STAR Institute of Bioengineering and Nanotechnology, Singapore, Singapore
| | | | - Myron Spector
- VA Boston Healthcare System, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Michael Young
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA.
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12
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Sengupta T, Koonce NL, Vázquez-Martínez N, Moyle MW, Duncan LH, Emerson SE, Han X, Shao L, Wu Y, Santella A, Fan L, Bao Z, Mohler W, Shroff H, Colón-Ramos DA. Differential adhesion regulates neurite placement via a retrograde zippering mechanism. eLife 2021; 10:71171. [PMID: 34783657 PMCID: PMC8843091 DOI: 10.7554/elife.71171] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Accepted: 11/15/2021] [Indexed: 11/13/2022] Open
Abstract
During development, neurites and synapses segregate into specific neighborhoods or layers within nerve bundles. The developmental programs guiding placement of neurites in specific layers, and hence their incorporation into specific circuits, are not well understood. We implement novel imaging methods and quantitative models to document the embryonic development of the C. elegans brain neuropil, and discover that differential adhesion mechanisms control precise placement of single neurites onto specific layers. Differential adhesion is orchestrated via developmentally-regulated expression of the IgCAM SYG-1, and its partner ligand SYG-2. Changes in SYG-1 expression across neuropil layers result in changes in adhesive forces, which sort SYG-2-expressing neurons. Sorting to layers occurs, not via outgrowth from the neurite tip, but via an alternate mechanism of retrograde zippering, involving interactions between neurite shafts. Our study indicates that biophysical principles from differential adhesion govern neurite placement and synaptic specificity in vivo in developing neuropil bundles.
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Affiliation(s)
- Titas Sengupta
- Yale University School of Medicine, New Haven, United States
| | - Noelle L Koonce
- Yale University School of Medicine, New Haven, United States
| | | | - Mark W Moyle
- Yale University School of Medicine, New Haven, United States
| | | | - Sarah E Emerson
- Yale University School of Medicine, New Haven, United States
| | - Xiaofei Han
- National Institutes of Health, Bethesda, United States
| | - Lin Shao
- Yale University School of Medicine, New Haven, United States
| | - Yicong Wu
- National Institutes of Health, Bethesda, United States
| | - Anthony Santella
- Developmental Biology Program, Molecular Cytology Core, Sloan-Kettering Institute, New York, United States
| | - Li Fan
- Helen and Robert Appel Alzheimer's Disease Institute, Weill Cornell Medicine, New York, United States
| | - Zhirong Bao
- Developmental Biology Program, Sloan-Kettering Institute, New York, United States
| | - William Mohler
- Department of Genetics and Developmental Biology, University of Connecticut Health Center, Farmington, United States
| | - Hari Shroff
- National Institutes of Health, Bethesda, United States
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13
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Mitovic N, Maksimovic S, Puflovic D, Kovacevic S, Lopicic S, Todorovic J, Spasic S, Dincic M, Ostojic JN. Cadmium significantly changes major morphometrical points and cardiovascular functional parameters during early development of zebrafish. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2021; 87:103723. [PMID: 34391906 DOI: 10.1016/j.etap.2021.103723] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 07/15/2021] [Accepted: 08/09/2021] [Indexed: 05/14/2023]
Abstract
Living organisms are commonly exposed to cadmium and other toxic metals. A vast body of research has shown the significant effects of these toxic metals on developmental processes. In order to study the role of toxic metals on early developmental stages of eukaryotes, we explored the effect of cadmium (Cd2+) contaminant on zebrafish. Thus, zebrafish embryos were exposed to 3 mg/L (16.7 μM) Cd2+ for 96 h and imaged every 24 h from the exposure onwards. Hatching rates of the eggs were determined at 72 h, followed by analyses at 96 h for: survival rate, morphometrical factors, and functional parameters of the cardiovascular system. Interestingly enough, significant hatching delays along with smaller cephalic region and some morphological abnormalities were observed in the treatment group. Moreover, substantial changes were noticed in the length of notochord and embryo, absorption of yolk sac with shorter extension, area of swimming bladder, as well as pericardium sac after Cd2+ treatment. Cadmium also caused significant abnormalities in heart physiology which could be the leading cause of mentioned morphological deformities. Herein, our results shine light on systematic acute embryological effects of cadmium in the early development of zebrafish for the first time.
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Affiliation(s)
- Nikola Mitovic
- Department of Pathophysiology, Medical Faculty, University of Belgrade, Belgrade, Serbia.
| | - Stefan Maksimovic
- Department of Pathophysiology, Medical Faculty, University of Belgrade, Belgrade, Serbia
| | - Darko Puflovic
- Faculty of Electronic Engineering, University of Nis, Nis, Serbia
| | - Sanjin Kovacevic
- Department of Pathophysiology, Medical Faculty, University of Belgrade, Belgrade, Serbia
| | - Srdjan Lopicic
- Department of Pathophysiology, Medical Faculty, University of Belgrade, Belgrade, Serbia
| | - Jasna Todorovic
- Department of Pathophysiology, Medical Faculty, University of Belgrade, Belgrade, Serbia
| | - Svetolik Spasic
- Department of Pathophysiology, Medical Faculty, University of Belgrade, Belgrade, Serbia
| | - Marko Dincic
- Department of Pathophysiology, Medical Faculty, University of Belgrade, Belgrade, Serbia
| | - Jelena Nesovic Ostojic
- Department of Pathophysiology, Medical Faculty, University of Belgrade, Belgrade, Serbia.
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14
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Parcerisas A, Ortega-Gascó A, Pujadas L, Soriano E. The Hidden Side of NCAM Family: NCAM2, a Key Cytoskeleton Organization Molecule Regulating Multiple Neural Functions. Int J Mol Sci 2021; 22:10021. [PMID: 34576185 PMCID: PMC8471948 DOI: 10.3390/ijms221810021] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 09/12/2021] [Accepted: 09/14/2021] [Indexed: 02/07/2023] Open
Abstract
Although it has been over 20 years since Neural Cell Adhesion Molecule 2 (NCAM2) was identified as the second member of the NCAM family with a high expression in the nervous system, the knowledge of NCAM2 is still eclipsed by NCAM1. The first studies with NCAM2 focused on the olfactory bulb, where this protein has a key role in axonal projection and axonal/dendritic compartmentalization. In contrast to NCAM1, NCAM2's functions and partners in the brain during development and adulthood have remained largely unknown until not long ago. Recent studies have revealed the importance of NCAM2 in nervous system development. NCAM2 governs neuronal morphogenesis and axodendritic architecture, and controls important neuron-specific processes such as neuronal differentiation, synaptogenesis and memory formation. In the adult brain, NCAM2 is highly expressed in dendritic spines, and it regulates synaptic plasticity and learning processes. NCAM2's functions are related to its ability to adapt to the external inputs of the cell and to modify the cytoskeleton accordingly. Different studies show that NCAM2 interacts with proteins involved in cytoskeleton stability and proteins that regulate calcium influx, which could also modify the cytoskeleton. In this review, we examine the evidence that points to NCAM2 as a crucial cytoskeleton regulation protein during brain development and adulthood. This key function of NCAM2 may offer promising new therapeutic approaches for the treatment of neurodevelopmental diseases and neurodegenerative disorders.
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Affiliation(s)
- Antoni Parcerisas
- Department of Cell Biology, Physiology and Immunology, Institute of Neurosciences, University of Barcelona, 08028 Barcelona, Spain; (A.O.-G.); (L.P.)
- Centro de Investigación Biomédica en Red Sobre Enfermedades Neurodegenerativas (CIBERNED), 28031 Madrid, Spain
- Department of Basic Sciences, Universitat Internacional de Catalunya, 08195 Sant Cugat del Vallès, Spain
| | - Alba Ortega-Gascó
- Department of Cell Biology, Physiology and Immunology, Institute of Neurosciences, University of Barcelona, 08028 Barcelona, Spain; (A.O.-G.); (L.P.)
- Centro de Investigación Biomédica en Red Sobre Enfermedades Neurodegenerativas (CIBERNED), 28031 Madrid, Spain
| | - Lluís Pujadas
- Department of Cell Biology, Physiology and Immunology, Institute of Neurosciences, University of Barcelona, 08028 Barcelona, Spain; (A.O.-G.); (L.P.)
- Centro de Investigación Biomédica en Red Sobre Enfermedades Neurodegenerativas (CIBERNED), 28031 Madrid, Spain
| | - Eduardo Soriano
- Department of Cell Biology, Physiology and Immunology, Institute of Neurosciences, University of Barcelona, 08028 Barcelona, Spain; (A.O.-G.); (L.P.)
- Centro de Investigación Biomédica en Red Sobre Enfermedades Neurodegenerativas (CIBERNED), 28031 Madrid, Spain
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15
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Parcerisas A, Ortega-Gascó A, Hernaiz-Llorens M, Odena MA, Ulloa F, de Oliveira E, Bosch M, Pujadas L, Soriano E. New Partners Identified by Mass Spectrometry Assay Reveal Functions of NCAM2 in Neural Cytoskeleton Organization. Int J Mol Sci 2021; 22:ijms22147404. [PMID: 34299022 PMCID: PMC8304497 DOI: 10.3390/ijms22147404] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 07/06/2021] [Accepted: 07/07/2021] [Indexed: 02/06/2023] Open
Abstract
Neuronal cell adhesion molecule 2 (NCAM2) is a membrane protein with an important role in the morphological development of neurons. In the cortex and the hippocampus, NCAM2 is essential for proper neuronal differentiation, dendritic and axonal outgrowth and synapse formation. However, little is known about NCAM2 functional mechanisms and its interactive partners during brain development. Here we used mass spectrometry to study the molecular interactome of NCAM2 in the second postnatal week of the mouse cerebral cortex. We found that NCAM2 interacts with >100 proteins involved in numerous processes, including neuronal morphogenesis and synaptogenesis. We validated the most relevant interactors, including Neurofilaments (NEFs), Microtubule-associated protein 2 (MAP2), Calcium/calmodulin kinase II alpha (CaMKIIα), Actin and Nogo. An in silico analysis of the cytosolic tail of the NCAM2.1 isoform revealed specific phosphorylation site motifs with a putative affinity for some of these interactors. Our results expand the knowledge of NCAM2 interactome and confirm the key role of NCAM2 in cytoskeleton organization, neuronal morphogenesis and synaptogenesis. These findings are of interest in explaining the phenotypes observed in different pathologies with alterations in the NCAM2 gene.
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Affiliation(s)
- Antoni Parcerisas
- Department of Cell Biology, Physiology and Immunology, University of Barcelona and Institute of Neurosciences, 08028 Barcelona, Spain; (A.O.-G.); (M.H.-L.); (F.U.); (L.P.)
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), 28031 Madrid, Spain
- Department of Basic Sciences, Universitat Internacional de Catalunya, 08195 Sant Cugat del Vallès, Spain;
- Correspondence: (A.P.); (E.S.)
| | - Alba Ortega-Gascó
- Department of Cell Biology, Physiology and Immunology, University of Barcelona and Institute of Neurosciences, 08028 Barcelona, Spain; (A.O.-G.); (M.H.-L.); (F.U.); (L.P.)
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), 28031 Madrid, Spain
| | - Marc Hernaiz-Llorens
- Department of Cell Biology, Physiology and Immunology, University of Barcelona and Institute of Neurosciences, 08028 Barcelona, Spain; (A.O.-G.); (M.H.-L.); (F.U.); (L.P.)
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), 28031 Madrid, Spain
| | - Maria Antonia Odena
- Plataforma de Proteòmica, Parc Científic de Barcelona (PCB), 08028 Barcelona, Spain; (M.A.O.); (E.d.O.)
| | - Fausto Ulloa
- Department of Cell Biology, Physiology and Immunology, University of Barcelona and Institute of Neurosciences, 08028 Barcelona, Spain; (A.O.-G.); (M.H.-L.); (F.U.); (L.P.)
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), 28031 Madrid, Spain
| | - Eliandre de Oliveira
- Plataforma de Proteòmica, Parc Científic de Barcelona (PCB), 08028 Barcelona, Spain; (M.A.O.); (E.d.O.)
| | - Miquel Bosch
- Department of Basic Sciences, Universitat Internacional de Catalunya, 08195 Sant Cugat del Vallès, Spain;
| | - Lluís Pujadas
- Department of Cell Biology, Physiology and Immunology, University of Barcelona and Institute of Neurosciences, 08028 Barcelona, Spain; (A.O.-G.); (M.H.-L.); (F.U.); (L.P.)
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), 28031 Madrid, Spain
| | - Eduardo Soriano
- Department of Cell Biology, Physiology and Immunology, University of Barcelona and Institute of Neurosciences, 08028 Barcelona, Spain; (A.O.-G.); (M.H.-L.); (F.U.); (L.P.)
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), 28031 Madrid, Spain
- Correspondence: (A.P.); (E.S.)
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16
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Mamon L, Yakimova A, Kopytova D, Golubkova E. The RNA-Binding Protein SBR (Dm NXF1) Is Required for the Constitution of Medulla Boundaries in Drosophila melanogaster Optic Lobes. Cells 2021; 10:1144. [PMID: 34068524 PMCID: PMC8151460 DOI: 10.3390/cells10051144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2021] [Revised: 05/05/2021] [Accepted: 05/06/2021] [Indexed: 11/17/2022] Open
Abstract
Drosophila melanogaster sbr (small bristles) is an orthologue of the Nxf1 (nuclear export factor 1) genes in different Opisthokonta. The known function of Nxf1 genes is the export of various mRNAs from the nucleus to the cytoplasm. The cytoplasmic localization of the SBR protein indicates that the nuclear export function is not the only function of this gene in Drosophila. RNA-binding protein SBR enriches the nucleus and cytoplasm of specific neurons and glial cells. In sbr12 mutant males, the disturbance of medulla boundaries correlates with the defects of photoreceptor axons pathfinding, axon bundle individualization, and developmental neurodegeneration. RNA-binding protein SBR participates in processes allowing axons to reach and identify their targets.
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Affiliation(s)
- Ludmila Mamon
- Department of Genetics and Biotechnology, Saint-Petersburg State University, Universitetskaya Emb. 7/9, 199034 St. Petersburg, Russia; or
| | - Anna Yakimova
- A. Tsyb Medical Radiological Research Center—Branch of the National Medical Research Radiological Center of the Ministry of Health of the Russian Federation, Koroleva Str. 4, 249036 Obninsk, Russia;
| | - Daria Kopytova
- Institute of Gene Biology, Russian Academy of Sciences, Vavilov St. 34/5, 119334 Moscow, Russia;
| | - Elena Golubkova
- Department of Genetics and Biotechnology, Saint-Petersburg State University, Universitetskaya Emb. 7/9, 199034 St. Petersburg, Russia; or
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17
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Savvaki M, Kafetzis G, Kaplanis SI, Ktena N, Theodorakis K, Karagogeos D. Neuronal, but not glial, Contactin 2 negatively regulates axon regeneration in the injured adult optic nerve. Eur J Neurosci 2021; 53:1705-1721. [PMID: 33469963 DOI: 10.1111/ejn.15121] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Revised: 12/26/2020] [Accepted: 01/17/2021] [Indexed: 01/09/2023]
Abstract
Mammalian adult neurons of the central nervous system (CNS) display limited ability to regrow axons after trauma. The developmental decline in their regenerative ability has been attributed to both intrinsic and extrinsic factors, including postnatal suppression of transcription factors and non-neuronal inhibitory components, respectively. The cell adhesion molecule Contactin 2 (CNTN2) is expressed in neurons and oligodendrocytes in the CNS. Neuronal CNTN2 is highly regulated during development and plays critical roles in axon growth and guidance and neuronal migration. On the other hand, CNTN2 expressed by oligodendrocytes interferes with the myelination process, with its ablation resulting in hypomyelination. In the current study, we investigate the role of CNTN2 in neuronal survival and axon regeneration after trauma, in the murine optic nerve crush (ONC) model. We unveil distinct roles for neuronal and glial CNTN2 in regenerative responses. Surprisingly, our data show a conflicting role of neuronal and glial CNTN2 in axon regeneration. Although glial CNTN2 as well as hypomyelination are dispensable for both neuronal survival and axon regeneration following ONC, the neuronal counterpart comprises a negative regulator of regeneration. Specifically, we reveal a novel mechanism of action for neuronal CNTN2, implicating the inhibition of Akt signalling pathway. The in vitro analysis indicates a BDNF-independent mode of action and biochemical data suggest the implication of the truncated form of TrkB neurotrophin receptor. In conclusion, CNTN2 expressed in CNS neurons serves as an inhibitor of axon regeneration after trauma and its mechanism of action involves the neutralization of Akt-mediated neuroprotective effects.
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Affiliation(s)
- Maria Savvaki
- Department of Basic Science, Faculty of Medicine, University of Crete, Crete, Greece.,Institute of Molecular Biology & Biotechnology - FoRTH, Heraklion, Crete, Greece
| | - George Kafetzis
- Department of Biology, University of Crete, Crete, Greece.,School of Life Sciences, University of Sussex, Brighton, UK
| | - Stefanos-Ioannis Kaplanis
- Department of Basic Science, Faculty of Medicine, University of Crete, Crete, Greece.,Institute of Molecular Biology & Biotechnology - FoRTH, Heraklion, Crete, Greece
| | - Niki Ktena
- Department of Basic Science, Faculty of Medicine, University of Crete, Crete, Greece.,Institute of Molecular Biology & Biotechnology - FoRTH, Heraklion, Crete, Greece
| | - Kostas Theodorakis
- Institute of Molecular Biology & Biotechnology - FoRTH, Heraklion, Crete, Greece
| | - Domna Karagogeos
- Department of Basic Science, Faculty of Medicine, University of Crete, Crete, Greece.,Institute of Molecular Biology & Biotechnology - FoRTH, Heraklion, Crete, Greece
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18
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de Agustín-Durán D, Mateos-White I, Fabra-Beser J, Gil-Sanz C. Stick around: Cell-Cell Adhesion Molecules during Neocortical Development. Cells 2021; 10:118. [PMID: 33435191 PMCID: PMC7826847 DOI: 10.3390/cells10010118] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 12/29/2020] [Accepted: 01/07/2021] [Indexed: 12/21/2022] Open
Abstract
The neocortex is an exquisitely organized structure achieved through complex cellular processes from the generation of neural cells to their integration into cortical circuits after complex migration processes. During this long journey, neural cells need to establish and release adhesive interactions through cell surface receptors known as cell adhesion molecules (CAMs). Several types of CAMs have been described regulating different aspects of neurodevelopment. Whereas some of them mediate interactions with the extracellular matrix, others allow contact with additional cells. In this review, we will focus on the role of two important families of cell-cell adhesion molecules (C-CAMs), classical cadherins and nectins, as well as in their effectors, in the control of fundamental processes related with corticogenesis, with special attention in the cooperative actions among the two families of C-CAMs.
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Affiliation(s)
| | | | | | - Cristina Gil-Sanz
- Neural Development Laboratory, Instituto Universitario de Biomedicina y Biotecnología (BIOTECMED) and Departamento de Biología Celular, Facultat de Biología, Universidad de Valencia, 46100 Burjassot, Spain; (D.d.A.-D.); (I.M.-W.); (J.F.-B.)
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19
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Abstract
Retinal ganglion cells (RGCs) serve as a crucial communication channel from the retina to the brain. In the adult, these cells receive input from defined sets of presynaptic partners and communicate with postsynaptic brain regions to convey features of the visual scene. However, in the developing visual system, RGC interactions extend beyond their synaptic partners such that they guide development before the onset of vision. In this Review, we summarize our current understanding of how interactions between RGCs and their environment influence cellular targeting, migration and circuit maturation during visual system development. We describe the roles of RGC subclasses in shaping unique developmental responses within the retina and at central targets. Finally, we highlight the utility of RNA sequencing and genetic tools in uncovering RGC type-specific roles during the development of the visual system.
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Affiliation(s)
- Shane D'Souza
- The Visual Systems Group, Cincinnati Children's Hospital, Cincinnati, OH 45229, USA
- Center for Chronobiology, Abrahamson Pediatric Eye Institute, Division of Pediatric Ophthalmology, Cincinnati Children's Hospital, Cincinnati, OH 45229, USA
- Molecular and Developmental Biology Graduate Program, University of Cincinnati, College of Medicine, Cincinnati, OH 45229, USA
| | - Richard A Lang
- The Visual Systems Group, Cincinnati Children's Hospital, Cincinnati, OH 45229, USA
- Center for Chronobiology, Abrahamson Pediatric Eye Institute, Division of Pediatric Ophthalmology, Cincinnati Children's Hospital, Cincinnati, OH 45229, USA
- Division of Developmental Biology, Cincinnati Children's Hospital, Cincinnati, OH 45229, USA
- Department of Ophthalmology, University of Cincinnati, College of Medicine, Cincinnati, OH 45229, USA
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20
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Patasova K, Hysi PG. The Slowly Emerging Uniqueness of the High Myopia Genetic Architecture. Ophthalmology 2020; 127:1625-1626. [PMID: 33222773 DOI: 10.1016/j.ophtha.2020.07.035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 07/17/2020] [Accepted: 07/21/2020] [Indexed: 11/26/2022] Open
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21
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Neural Cadherin Plays Distinct Roles for Neuronal Survival and Axon Growth under Different Regenerative Conditions. eNeuro 2020; 7:ENEURO.0325-20.2020. [PMID: 32967889 PMCID: PMC7688304 DOI: 10.1523/eneuro.0325-20.2020] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 08/26/2020] [Accepted: 08/28/2020] [Indexed: 12/18/2022] Open
Abstract
Growing axons in the CNS often migrate along specific pathways to reach their targets. During embryonic development, this migration is guided by different types of cell adhesion molecules (CAMs) present on the surface of glial cells or other neurons, including the neural cadherin (NCAD). Axons in the adult CNS can be stimulated to regenerate, and travel long distances. Crucially, however, while a few axons are guided effectively through the injured nerve under certain conditions, most axons never migrate properly. The molecular underpinnings of the variable growth, and the glial CAMs that are responsible for CNS axon regeneration remain unclear. Here we used optic nerve crush to demonstrate that NCAD plays multifaceted functions in facilitating CNS axon regeneration. Astrocyte-specific deletion of NCAD dramatically decreases regeneration induced by phosphatase and tensin homolog (PTEN) ablation in retinal ganglion cells (RGCs). Consistent with NCAD’s tendency to act as homodimers, deletion of NCAD in RGCs also reduces regeneration. Deletion of NCAD in astrocytes neither alters RGCs’ mammalian target of rapamycin complex 1 (mTORC1) activity nor lesion size, two factors known to affect regeneration. Unexpectedly, however, we find that NCAD deletion in RGCs reduces PTEN-deletion-induced RGC survival. We further show that NCAD deletion, in either astrocytes or RGCs, has negligible effects on the regeneration induced by ciliary neurotrophic factor (CNTF), suggesting that other CAMs are critical under this regenerative condition. Consistent with this notion, CNTF induces expression various integrins known to mediate cell adhesion. Together, our study reveals multilayered functions of NCAD and a molecular basis of variability in guided axon growth.
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22
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Wen W, Wang Y, Li H, Xu H, Xu M, Frank JA, Ma M, Luo J. Mesencephalic Astrocyte-Derived Neurotrophic Factor (MANF) Regulates Neurite Outgrowth Through the Activation of Akt/mTOR and Erk/mTOR Signaling Pathways. Front Mol Neurosci 2020; 13:560020. [PMID: 33071755 PMCID: PMC7541815 DOI: 10.3389/fnmol.2020.560020] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Accepted: 09/04/2020] [Indexed: 12/13/2022] Open
Abstract
Neurite outgrowth is essential for brain development and the recovery of brain injury and neurodegenerative diseases. In this study, we examined the role of the neurotrophic factor MANF in regulating neurite outgrowth. We generated MANF knockout (KO) neuro2a (N2a) cell lines using clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 and demonstrated that MANF KO N2a cells failed to grow neurites in response to RA stimulation. Using MANF siRNA, this finding was confirmed in human SH-SY5Y neuronal cell line. Nevertheless, MANF overexpression by adenovirus transduction or addition of MANF into culture media facilitated the growth of longer neurites in RA-treated N2a cells. MANF deficiency resulted in inhibition of Akt, Erk, mTOR, and P70S6, and impaired protein synthesis. MANF overexpression on the other hand facilitated the growth of longer neurites by activating Akt, Erk, mTOR, and P70S6. Pharmacological blockade of Akt, Erk or mTOR eliminated the promoting effect of MANF on neurite outgrowth. These findings suggest that MANF positively regulated neurite outgrowth by activating Akt/mTOR and Erk/mTOR signaling pathways.
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Affiliation(s)
- Wen Wen
- Department of Pathology, University of Iowa, Iowa City, IA, United States
| | - Yongchao Wang
- Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, KY, United States
| | - Hui Li
- Department of Pathology, University of Iowa, Iowa City, IA, United States
| | - Hong Xu
- Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, KY, United States
| | - Mei Xu
- Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, KY, United States
| | - Jacqueline A Frank
- Department of Neurology, University of Kentucky College of Medicine, Lexington, KY, United States
| | - Murong Ma
- Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, KY, United States
| | - Jia Luo
- Department of Pathology, University of Iowa, Iowa City, IA, United States
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23
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Trans-Axonal Signaling in Neural Circuit Wiring. Int J Mol Sci 2020; 21:ijms21145170. [PMID: 32708320 PMCID: PMC7404203 DOI: 10.3390/ijms21145170] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 07/15/2020] [Accepted: 07/17/2020] [Indexed: 12/24/2022] Open
Abstract
The development of neural circuits is a complex process that relies on the proper navigation of axons through their environment to their appropriate targets. While axon–environment and axon–target interactions have long been known as essential for circuit formation, communication between axons themselves has only more recently emerged as another crucial mechanism. Trans-axonal signaling governs many axonal behaviors, including fasciculation for proper guidance to targets, defasciculation for pathfinding at important choice points, repulsion along and within tracts for pre-target sorting and target selection, repulsion at the target for precise synaptic connectivity, and potentially selective degeneration for circuit refinement. This review outlines the recent advances in identifying the molecular mechanisms of trans-axonal signaling and discusses the role of axon–axon interactions during the different steps of neural circuit formation.
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24
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Kiyama T, Long Y, Chen CK, Whitaker CM, Shay A, Wu H, Badea TC, Mohsenin A, Parker-Thornburg J, Klein WH, Mills SL, Massey SC, Mao CA. Essential Roles of Tbr1 in the Formation and Maintenance of the Orientation-Selective J-RGCs and a Group of OFF-Sustained RGCs in Mouse. Cell Rep 2020; 27:900-915.e5. [PMID: 30995485 DOI: 10.1016/j.celrep.2019.03.077] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Revised: 02/10/2019] [Accepted: 03/20/2019] [Indexed: 01/27/2023] Open
Abstract
In the mouse retina, more than 30 retinal ganglion cell (RGC) subtypes have been classified based on a combined metric of morphological and functional characteristics. RGCs arise from a common pool of retinal progenitor cells during embryonic stages and differentiate into mature subtypes in adult retinas. However, the cellular and molecular mechanisms controlling formation and maturation of such remarkable cellular diversity remain unknown. Here, we demonstrate that T-box transcription factor T-brain 1 (Tbr1) is expressed in two groups of morphologically and functionally distinct RGCs: the orientation-selective J-RGCs and a group of OFF-sustained RGCs with symmetrical dendritic arbors. When Tbr1 is genetically ablated during retinal development, these two RGC groups cannot develop. Ectopically expressing Tbr1 in M4 ipRGCs during development alters dendritic branching and density but not the inner plexiform layer stratification level. Our data indicate that Tbr1 plays critical roles in regulating the formation and dendritic morphogenesis of specific RGC types.
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Affiliation(s)
- Takae Kiyama
- Ruiz Department of Ophthalmology and Visual Science, McGovern Medical School at The University of Texas Health Science Center at Houston (UTHealth), Houston, TX 77030, USA
| | - Ye Long
- Ruiz Department of Ophthalmology and Visual Science, McGovern Medical School at The University of Texas Health Science Center at Houston (UTHealth), Houston, TX 77030, USA
| | - Ching-Kang Chen
- Department of Ophthalmology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Christopher M Whitaker
- Ruiz Department of Ophthalmology and Visual Science, McGovern Medical School at The University of Texas Health Science Center at Houston (UTHealth), Houston, TX 77030, USA
| | - Allison Shay
- Department of Ophthalmology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Hongyu Wu
- Ruiz Department of Ophthalmology and Visual Science, McGovern Medical School at The University of Texas Health Science Center at Houston (UTHealth), Houston, TX 77030, USA
| | - Tudor C Badea
- National Eye Institute, NIH, Bethesda, MD 20892, USA
| | - Amir Mohsenin
- Ruiz Department of Ophthalmology and Visual Science, McGovern Medical School at The University of Texas Health Science Center at Houston (UTHealth), Houston, TX 77030, USA; Robert Cizik Eye Clinic, Houston, TX 77030, USA
| | - Jan Parker-Thornburg
- Department of Genetics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - William H Klein
- Department of Systems Biology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Stephen L Mills
- Ruiz Department of Ophthalmology and Visual Science, McGovern Medical School at The University of Texas Health Science Center at Houston (UTHealth), Houston, TX 77030, USA
| | - Stephen C Massey
- Ruiz Department of Ophthalmology and Visual Science, McGovern Medical School at The University of Texas Health Science Center at Houston (UTHealth), Houston, TX 77030, USA
| | - Chai-An Mao
- Ruiz Department of Ophthalmology and Visual Science, McGovern Medical School at The University of Texas Health Science Center at Houston (UTHealth), Houston, TX 77030, USA.
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25
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Parcerisas A, Pujadas L, Ortega-Gascó A, Perelló-Amorós B, Viais R, Hino K, Figueiro-Silva J, La Torre A, Trullás R, Simó S, Lüders J, Soriano E. NCAM2 Regulates Dendritic and Axonal Differentiation through the Cytoskeletal Proteins MAP2 and 14-3-3. Cereb Cortex 2020; 30:3781-3799. [PMID: 32043120 DOI: 10.1093/cercor/bhz342] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 11/27/2019] [Accepted: 01/08/2020] [Indexed: 01/13/2023] Open
Abstract
Neural cell adhesion molecule 2 (NCAM2) is involved in the development and plasticity of the olfactory system. Genetic data have implicated the NCAM2 gene in neurodevelopmental disorders including Down syndrome and autism, although its role in cortical development is unknown. Here, we show that while overexpression of NCAM2 in hippocampal neurons leads to minor alterations, its downregulation severely compromises dendritic architecture, leading to an aberrant phenotype including shorter dendritic trees, retraction of dendrites, and emergence of numerous somatic neurites. Further, our data reveal alterations in the axonal tree and deficits in neuronal polarization. In vivo studies confirm the phenotype and reveal an unexpected role for NCAM2 in cortical migration. Proteomic and cell biology experiments show that NCAM2 molecules exert their functions through a protein complex with the cytoskeletal-associated proteins MAP2 and 14-3-3γ and ζ. We provide evidence that NCAM2 depletion results in destabilization of the microtubular network and reduced MAP2 signal. Our results demonstrate a role for NCAM2 in dendritic formation and maintenance, and in neural polarization and migration, through interaction of NCAM2 with microtubule-associated proteins.
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Affiliation(s)
- Antoni Parcerisas
- Department of Cell Biology, Physiology and Immunology, and Institute of Neurosciences, University of Barcelona, 08028 Barcelona, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), 28031, Madrid, Spain.,Vall d'Hebron Institut de Recerca (VHIR), 08035, Barcelona, Spain
| | - Lluís Pujadas
- Department of Cell Biology, Physiology and Immunology, and Institute of Neurosciences, University of Barcelona, 08028 Barcelona, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), 28031, Madrid, Spain.,Vall d'Hebron Institut de Recerca (VHIR), 08035, Barcelona, Spain
| | - Alba Ortega-Gascó
- Department of Cell Biology, Physiology and Immunology, and Institute of Neurosciences, University of Barcelona, 08028 Barcelona, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), 28031, Madrid, Spain.,Vall d'Hebron Institut de Recerca (VHIR), 08035, Barcelona, Spain
| | - Bartomeu Perelló-Amorós
- Department of Cell Biology, Physiology and Immunology, and Institute of Neurosciences, University of Barcelona, 08028 Barcelona, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), 28031, Madrid, Spain.,Vall d'Hebron Institut de Recerca (VHIR), 08035, Barcelona, Spain
| | - Ricardo Viais
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona Institute of Science and Technology (BIST), 08028, Barcelona, Spain
| | - Keiko Hino
- Department of Cell Biology and Human Anatomy, University of California, Davis, CA 95616, USA
| | - Joana Figueiro-Silva
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), 28031, Madrid, Spain.,Neurobiology Unit, Institut d'Investigacions Biomèdiques de Barcelona, CSIC, IDIBAPS, 08036, Barcelona, Spain
| | - Anna La Torre
- Department of Cell Biology and Human Anatomy, University of California, Davis, CA 95616, USA
| | - Ramón Trullás
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), 28031, Madrid, Spain.,Neurobiology Unit, Institut d'Investigacions Biomèdiques de Barcelona, CSIC, IDIBAPS, 08036, Barcelona, Spain
| | - Sergi Simó
- Department of Cell Biology and Human Anatomy, University of California, Davis, CA 95616, USA
| | - Jens Lüders
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona Institute of Science and Technology (BIST), 08028, Barcelona, Spain
| | - Eduardo Soriano
- Department of Cell Biology, Physiology and Immunology, and Institute of Neurosciences, University of Barcelona, 08028 Barcelona, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), 28031, Madrid, Spain.,Vall d'Hebron Institut de Recerca (VHIR), 08035, Barcelona, Spain.,Institució Catalana de Recerca i Estudis Avançats (ICREA) Academia, 08010, Barcelona, Spain
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26
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Wang A, Xiang YY, Yang BB, Lu WY. Neurexin-1α regulates neurite growth of rat hippocampal neurons. INTERNATIONAL JOURNAL OF PHYSIOLOGY, PATHOPHYSIOLOGY AND PHARMACOLOGY 2019; 11:115-125. [PMID: 31523359 PMCID: PMC6737430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Accepted: 08/12/2019] [Indexed: 06/10/2023]
Abstract
The growth of neurites underlies the axonal pathfinding and synaptic formation during neuronal development and regeneration. Neurite growth is regulated by specific interactions between growth cone receptors and their ligands that function as molecular cues existing in microenvironments. Neurexins (NRXNs) are concentrated on growth cones and they may function to constrain axonal branches of invertebrate neurons. The present study explored the role of NRXN-1α in regulating neurite growth of mammalian neurons. Results showed that transfecting an effective NRXN-1α siRNA to cultured rat hippocampal neurons significantly increased neurite length. Adding NRXN-1α ligands including neuroligin (NLGN) peptide and/or α-latrotoxin (α-LTX) to the culture media largely decreased neurite growth of naïve neurons in a Ca2+-dependent manner, but had no effect on neurite growth of neurons transfected with NRXN-1α siRNA. Our results suggest that NRXN-1α regulates neurite development of mammalian neurons.
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Affiliation(s)
- Adam Wang
- Department of Physiology and Pharmacology, The University of Western OntarioLondon, Ontario N6A 5B7, Canada
| | - Yun-Yan Xiang
- Robarts Research Institute, The University of Western OntarioLondon, Ontario N6A 5B7, Canada
| | - Burton B Yang
- Department of Laboratory Medicine and Pathobiology, University of TorontoCanada
- Sunnybrook Research Institute, University of TorontoCanada
| | - Wei-Yang Lu
- Department of Physiology and Pharmacology, The University of Western OntarioLondon, Ontario N6A 5B7, Canada
- Robarts Research Institute, The University of Western OntarioLondon, Ontario N6A 5B7, Canada
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27
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Picocci S, Bizzoca A, Corsi P, Magrone T, Jirillo E, Gennarini G. Modulation of Nerve Cell Differentiation: Role of Polyphenols and of Contactin Family Components. Front Cell Dev Biol 2019; 7:119. [PMID: 31380366 PMCID: PMC6656924 DOI: 10.3389/fcell.2019.00119] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 06/12/2019] [Indexed: 12/18/2022] Open
Abstract
In this study the mechanisms are explored, which modulate expression and function of cell surface adhesive glycoproteins of the Immunoglobulin Supergene Family (IgSF), and in particular of its Contactin subset, during neuronal precursor developmental events. In this context, a specific topic concerns the significance of the expression profile of such molecules and their ability to modulate signaling pathways activated through nutraceuticals, in particular polyphenols, administration. Both in vitro and in vivo approaches are chosen. As for the former, by using as a model the human SH-SY5Y neuroblastoma line, the effects of grape seed polyphenols are evaluated on proliferation and commitment/differentiation events along the neuronal lineage. In SH-SY5Y cell cultures, polyphenols were found to counteract precursor proliferation while promoting their differentiation, as deduced by studying their developmental parameters through the expression of cell cycle and neuronal commitment/differentiation markers as well as by measuring neurite growth. In such cultures, Cyclin E expression and BrdU incorporation were downregulated, indicating reduced precursor proliferation while increased neuronal differentiation was inferred from upregulation of cell cycle exit (p27–Kip) and neuronal commitment (NeuN) markers as well as by measuring neurite length through morphometric analysis. The polyphenol effects on developmental parameters were also explored in vivo, in cerebellar cortex, by using as a model the TAG/F3 transgenic line, which undergoes delayed neural development as a consequence of Contactin1 adhesive glycoprotein upregulation and premature expression under control of the Contactin2 gene (Cntn-2) promoter. In this transgenic line, a Notch pathway activation is known to occur and polyphenol treatment was found to counteract such an effect, demonstrated through downregulation of the Hes-1 transcription factor. Polyphenols also downregulated the expression of adhesive glycoproteins of the Contactin family themselves, demonstrated for both Contactin1 and Contactin2, indicating the involvement of changes in the expression of the underlying genes in the observed phenotype. These data support the hypothesis that the complex control exerted by polyphenols on neural development involves modulation of expression and function of the genes encoding cell adhesion molecules of the Contactin family and of the associated signaling pathways, indicating potential mechanisms whereby such compounds may control neurogenesis.
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Affiliation(s)
- Sabrina Picocci
- Laboratories of Developmental Neurobiology, Department of Basic Medical Sciences, Neurosciences and Sensory Organs, Medical School, University of Bari Aldo Moro, Bari, Italy
| | - Antonella Bizzoca
- Laboratories of Developmental Neurobiology, Department of Basic Medical Sciences, Neurosciences and Sensory Organs, Medical School, University of Bari Aldo Moro, Bari, Italy
| | - Patrizia Corsi
- Laboratories of Developmental Neurobiology, Department of Basic Medical Sciences, Neurosciences and Sensory Organs, Medical School, University of Bari Aldo Moro, Bari, Italy
| | - Thea Magrone
- Laboratories of Immunology, Department of Basic Medical Sciences, Neurosciences and Sensory Organs, Medical School, University of Bari Aldo Moro, Bari, Italy
| | - Emilio Jirillo
- Laboratories of Immunology, Department of Basic Medical Sciences, Neurosciences and Sensory Organs, Medical School, University of Bari Aldo Moro, Bari, Italy
| | - Gianfranco Gennarini
- Laboratories of Developmental Neurobiology, Department of Basic Medical Sciences, Neurosciences and Sensory Organs, Medical School, University of Bari Aldo Moro, Bari, Italy
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28
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Modulation of cell-cell interactions for neural tissue engineering: Potential therapeutic applications of cell adhesion molecules in nerve regeneration. Biomaterials 2019; 197:327-344. [DOI: 10.1016/j.biomaterials.2019.01.030] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Revised: 12/08/2018] [Accepted: 01/20/2019] [Indexed: 12/21/2022]
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29
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Papal S, Monti CE, Tennison ME, Swaroop A. Molecular dissection of cone photoreceptor-enriched genes encoding transmembrane and secretory proteins. J Neurosci Res 2018; 97:16-28. [PMID: 30260491 DOI: 10.1002/jnr.24329] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Revised: 08/21/2018] [Accepted: 08/28/2018] [Indexed: 12/13/2022]
Abstract
Cone photoreceptors mediate color perception and daylight vision through intricate synaptic circuitry. In most mammalian retina, cones are greatly outnumbered by rods and exhibit inter-dependence for functional maintenance and survival. Currently, we have limited understanding of cone-specific molecular components that mediate response to extrinsic signaling factors or are involved in communication with rods and other retinal cells. To fulfill this gap, we compared the recently-published transcriptomes of developing S-cone-like photoreceptors from the Nrl-/- mouse retina with those of rods and identified candidate genes responsible for cone cell functions and communication. We generated an in silico expression profile of 823 genes that encode candidate transmembrane and secretory proteins and are up-regulated in Nrl-/- cone photoreceptors compared to wild type cones. In situ hybridization analysis validated high expression of seven of the selected candidate genes in the Nrl-/- retina. To examine their relevance to cone function, we performed in vivo knockdown of Epha10 in the Nrl-/- retina and demonstrated aberrant morphology and mislocalization of the photoreceptor cell bodies. Thus, the receptor tyrosine kinase Ephrin type-A receptor 10 appears to influence cone morphogenesis. Our studies reveal novel cone-enriched genes involved in interaction of cones with other retinal cell types and provide a framework for examining molecular pathways associated with intercellular communication.
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Affiliation(s)
- Samantha Papal
- Neurobiology-Neurodegeneration & Repair Laboratory, National Eye Institute, National Institutes of Health, Bethesda, Maryland
| | - Christopher E Monti
- Neurobiology-Neurodegeneration & Repair Laboratory, National Eye Institute, National Institutes of Health, Bethesda, Maryland
| | - Mackenzie E Tennison
- Neurobiology-Neurodegeneration & Repair Laboratory, National Eye Institute, National Institutes of Health, Bethesda, Maryland
| | - Anand Swaroop
- Neurobiology-Neurodegeneration & Repair Laboratory, National Eye Institute, National Institutes of Health, Bethesda, Maryland
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30
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Effect of acupuncture at Renying (ST 9) on gene expression profile of hypothalamus in spontaneously hypertensive rats. J TRADIT CHIN MED 2018. [DOI: 10.1016/j.jtcm.2018.04.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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31
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Southam KA, Stennard F, Pavez C, Small DH. Knockout of Amyloid β Protein Precursor (APP) Expression Alters Synaptogenesis, Neurite Branching and Axonal Morphology of Hippocampal Neurons. Neurochem Res 2018; 44:1346-1355. [PMID: 29572646 DOI: 10.1007/s11064-018-2512-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Revised: 03/15/2018] [Accepted: 03/20/2018] [Indexed: 12/23/2022]
Abstract
The function of the β-A4 amyloid protein precursor (APP) of Alzheimer's disease (AD) remains unclear. APP has a number of putative roles in neuronal differentiation, survival, synaptogenesis and cell adhesion. In this study, we examined the development of axons, dendrites and synapses in cultures of hippocampus neutrons derived from APP knockout (KO) mice. We report that loss of APP function reduces the branching of cultured hippocampal neurons, resulting in reduced synapse formation. Using a compartmentalised culture approach, we found reduced axonal outgrowth in cultured hippocampal neurons and we also identified abnormal growth characteristics of isolated hippocampal neuron axons. Although APP has previously been suggested to play an important role in promoting cell adhesion, we surprisingly found that APPKO hippocampal neurons adhered more strongly to a poly-L-lysine substrate and their neurites displayed an increased density of focal adhesion puncta. The findings suggest that the function of APP has an important role in both dendritic and axonal growth and that endogenous APP may regulate substrate adhesion of hippocampal neurons. The results may explain neuronal and synaptic morphological abnormalities in APPKO mice and the presence of abnormal APP expression in dystrophic neurites around amyloid deposits in AD.
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Affiliation(s)
- Katherine A Southam
- Menzies Institute for Medical Research, University of Tasmania, Hobart, TAS, 7000, Australia. .,Faculty of Health, School of Medicine, University of Tasmania, 17 Liverpool Street, Hobart, TAS, 7000, Australia.
| | - Fiona Stennard
- Menzies Institute for Medical Research, University of Tasmania, Hobart, TAS, 7000, Australia
| | - Cassandra Pavez
- Menzies Institute for Medical Research, University of Tasmania, Hobart, TAS, 7000, Australia
| | - David H Small
- Menzies Institute for Medical Research, University of Tasmania, Hobart, TAS, 7000, Australia
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32
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Membrane cholesterol mediates the cellular effects of monolayer graphene substrates. Nat Commun 2018; 9:796. [PMID: 29476054 PMCID: PMC5824811 DOI: 10.1038/s41467-018-03185-0] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2016] [Accepted: 01/25/2018] [Indexed: 01/07/2023] Open
Abstract
Graphene possesses extraordinary properties that promise great potential in biomedicine. However, fully leveraging these properties requires close contact with the cell surface, raising the concern of unexpected biological consequences. Computational models have demonstrated that graphene preferentially interacts with cholesterol, a multifunctional lipid unique to eukaryotic membranes. Here we demonstrate an interaction between graphene and cholesterol. We find that graphene increases cell membrane cholesterol and potentiates neurotransmission, which is mediated by increases in the number, release probability, and recycling rate of synaptic vesicles. In fibroblasts grown on graphene, we also find an increase in cholesterol, which promotes the activation of P2Y receptors, a family of receptor regulated by cholesterol. In both cases, direct manipulation of cholesterol levels elucidates that a graphene-induced cholesterol increase underlies the observed potentiation of each cell signaling pathway. These findings identify cholesterol as a mediator of graphene’s cellular effects, providing insight into the biological impact of graphene. Understanding the biological role of graphene in eukaryotic cells is essential for future biomedicine applications. Here, the authors investigate the interaction of neurons and fibroblasts with graphene substrates, which increase cell membrane cholesterol and potentiate neurotransmitter release and receptor signaling.
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33
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Sakurai T. The role of cell adhesion molecules in brain wiring and neuropsychiatric disorders. Mol Cell Neurosci 2017; 81:4-11. [PMID: 27561442 DOI: 10.1016/j.mcn.2016.08.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Revised: 08/16/2016] [Accepted: 08/19/2016] [Indexed: 12/15/2022] Open
Abstract
Cell adhesion molecules (CAMs) in the nervous system have long been a research focus, but many mice lacking CAMs show very subtle phenotypes, giving an impression that CAMs may not be major players in constructing the nervous system. However, recent human genetic studies suggest CAM involvement in many neuropsychiatric disorders, implicating that they must have significant functions in nervous system development, namely in circuitry formation. As CAMs can provide specificity through their molecular interactions, this review summarizes possible mechanisms on how alterations of CAMs can result in neuropsychiatric disorders through circuitry modification.
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Affiliation(s)
- Takeshi Sakurai
- Medical Innovation Center, Kyoto University Graduate School of Medicine, 53 Shogoin Kawaharacho, Sakyo-ku, Kyoto, 606-8507, Japan.
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34
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Chen YT, Tai CY. μ2-Dependent endocytosis of N-cadherin is regulated by β-catenin to facilitate neurite outgrowth. Traffic 2017; 18:287-303. [DOI: 10.1111/tra.12473] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Revised: 02/10/2017] [Accepted: 02/17/2017] [Indexed: 01/07/2023]
Affiliation(s)
- Yi-ting Chen
- Taiwan International Graduate Program, Molecular and Cellular Biology Program; Academia Sinica; Taiwan Republic of China
- Institute of Molecular Biology; Academia Sinica; Taiwan Republic of China
- Graduate Institute of Life Sciences, National Defense Medical Center; Taiwan Republic of China
| | - Chin-Yin Tai
- Taiwan International Graduate Program, Molecular and Cellular Biology Program; Academia Sinica; Taiwan Republic of China
- Institute of Molecular Biology; Academia Sinica; Taiwan Republic of China
- Development Center for Biotechnology; Institute of Pharmaceutics; Taiwan Republic of China
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35
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Tedeschi A, Bradke F. Spatial and temporal arrangement of neuronal intrinsic and extrinsic mechanisms controlling axon regeneration. Curr Opin Neurobiol 2016; 42:118-127. [PMID: 28039763 DOI: 10.1016/j.conb.2016.12.005] [Citation(s) in RCA: 92] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Revised: 12/07/2016] [Accepted: 12/08/2016] [Indexed: 01/30/2023]
Abstract
Axon regeneration and neuronal tissue repair varies across animal lineages as well as in the mammalian central and peripheral nervous systems. While the peripheral nervous system retains the ability to self-repair, the majority of axons in the adult mammalian central nervous system (CNS) fail to reactivate intrinsic growth programs after injury. Recent findings, however, suggest that long-distance axon regeneration, neuronal circuit assembly and recovery of functions in the adult mammalian CNS are possible. Here, we discuss our current knowledge of the cell signaling pathways and networks controlling axon regeneration. In addition, we outline a number of combinatorial strategies that include among others microtubule-based treatments to foster regeneration and functional connectivity after CNS trauma.
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Affiliation(s)
- Andrea Tedeschi
- German Center for Neurodegenerative Diseases (DZNE), Ludwig-Erhard-Allee 2, 53175 Bonn, Germany.
| | - Frank Bradke
- German Center for Neurodegenerative Diseases (DZNE), Ludwig-Erhard-Allee 2, 53175 Bonn, Germany.
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36
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Gennarini G, Bizzoca A, Picocci S, Puzzo D, Corsi P, Furley AJW. The role of Gpi-anchored axonal glycoproteins in neural development and neurological disorders. Mol Cell Neurosci 2016; 81:49-63. [PMID: 27871938 DOI: 10.1016/j.mcn.2016.11.006] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2016] [Revised: 11/10/2016] [Accepted: 11/14/2016] [Indexed: 01/06/2023] Open
Abstract
This review article focuses on the Contactin (CNTN) subset of the Immunoglobulin supergene family (IgC2/FNIII molecules), whose components share structural properties (the association of Immunoglobulin type C2 with Fibronectin type III domains), as well as a general role in cell contact formation and axonal growth control. IgC2/FNIII molecules include 6 highly related components (CNTN 1-6), associated with the cell membrane via a Glycosyl Phosphatidyl Inositol (GPI)-containing lipid tail. Contactin 1 and Contactin 2 share ~50 (49.38)% identity at the aminoacid level. They are components of the cell surface, from which they may be released in soluble forms. They bind heterophilically to multiple partners in cis and in trans, including members of the related L1CAM family and of the Neurexin family Contactin-associated proteins (CNTNAPs or Casprs). Such interactions are important for organising the neuronal membrane, as well as for modulating the growth and pathfinding of axon tracts. In addition, they also mediate the functional maturation of axons by promoting their interactions with myelinating cells at the nodal, paranodal and juxtaparanodal regions. Such interactions also mediate differential ionic channels (both Na+ and K+) distribution, which is of critical relevance in the generation of the peak-shaped action potential. Indeed, thanks to their interactions with Ankyrin G, Na+ channels map within the nodal regions, where they drive axonal depolarization. However, no ionic channels are found in the flanking Contactin1-containing paranodal regions, where CNTN1 interactions with Caspr1 and with the Ig superfamily component Neurofascin 155 in cis and in trans, respectively, build a molecular barrier between the node and the juxtaparanode. In this region K+ channels are clustered, depending upon molecular interactions with Contactin 2 and with Caspr2. In addition to these functions, the Contactins appear to have also a role in degenerative and inflammatory disorders: indeed Contactin 2 is involved in neurodegenerative disorders with a special reference to the Alzheimer disease, given its ability to work as a ligand of the Alzheimer Precursor Protein (APP), which results in increased Alzheimer Intracellular Domain (AICD) release in a γ-secretase-dependent manner. On the other hand Contactin 1 drives Notch signalling activation via the Hes pathway, which could be consistent with its ability to modulate neuroinflammation events, and with the possibility that Contactin 1-dependent interactions may participate to the pathogenesis of the Multiple Sclerosis and of other inflammatory disorders.
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Affiliation(s)
- Gianfranco Gennarini
- Department of Basic Medical Sciences, Neurosciences and Sensory Organs, Medical School, University of Bari Policlinico. Piazza Giulio Cesare. I-70124 Bari, Italy.
| | - Antonella Bizzoca
- Department of Basic Medical Sciences, Neurosciences and Sensory Organs, Medical School, University of Bari Policlinico. Piazza Giulio Cesare. I-70124 Bari, Italy
| | - Sabrina Picocci
- Department of Basic Medical Sciences, Neurosciences and Sensory Organs, Medical School, University of Bari Policlinico. Piazza Giulio Cesare. I-70124 Bari, Italy
| | - Daniela Puzzo
- Department of Biomedical and Biotechnological Sciences, University of Catania, Italy
| | - Patrizia Corsi
- Department of Basic Medical Sciences, Neurosciences and Sensory Organs, Medical School, University of Bari Policlinico. Piazza Giulio Cesare. I-70124 Bari, Italy
| | - Andrew J W Furley
- Department of Biomedical Science, University of Sheffield, Western Bank, Sheffield S10 2NT, UK
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37
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Frei JA, Stoeckli ET. SynCAMs - From axon guidance to neurodevelopmental disorders. Mol Cell Neurosci 2016; 81:41-48. [PMID: 27594578 DOI: 10.1016/j.mcn.2016.08.012] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Revised: 08/28/2016] [Accepted: 08/31/2016] [Indexed: 12/22/2022] Open
Abstract
Many cell adhesion molecules are located at synapses but only few of them can be considered synaptic cell adhesion molecules in the strict sense. Besides the Neurexins and Neuroligins, the LRRTMs (leucine rich repeat transmembrane proteins) and the SynCAMs/CADMs can induce synapse formation when expressed in non-neuronal cells and therefore are true synaptic cell adhesion molecules. SynCAMs (synaptic cell adhesion molecules) are a subfamily of the immunoglobulin superfamily of cell adhesion molecules. As suggested by their name, they were first identified as cell adhesion molecules at the synapse which were sufficient to trigger synapse formation. They also contribute to myelination by mediating axon-glia cell contacts. More recently, their role in earlier stages of neural circuit formation was demonstrated, as they also guide axons both in the peripheral and in the central nervous system. Mutations in SynCAM genes were found in patients diagnosed with autism spectrum disorders. The diverse functions of SynCAMs during development suggest that neurodevelopmental disorders are not only due to defects in synaptic plasticity. Rather, early steps of neural circuit formation are likely to contribute.
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Affiliation(s)
- Jeannine A Frei
- Hussman Institute for Autism, 801 W Baltimore Street, Baltimore, MD 20201, United States
| | - Esther T Stoeckli
- Dept of Molecular Life Sciences and Neuroscience Center Zurich, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland.
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38
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Faye PA, Vedrenne N, De la Cruz-Morcillo MA, Barrot CC, Richard L, Bourthoumieu S, Sturtz F, Funalot B, Lia AS, Battu S. New Method for Sorting Endothelial and Neural Progenitors from Human Induced Pluripotent Stem Cells by Sedimentation Field Flow Fractionation. Anal Chem 2016; 88:6696-702. [PMID: 27263863 DOI: 10.1021/acs.analchem.6b00704] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Human induced pluripotent stem cells (hiPSc) are a very useful solution to create and observe the behavior of specific and usually inaccessible cells, such as human motor neurons. Obtained from a patient biopsy by reprograming dermal fibroblasts (DF), hiPSc present the same properties as embryonic stem cells and can generate any cell type after several weeks of differentiation. Today, there are numerus protocols which aim to control hiPSC differentiation. The principal challenge is to obtain a sufficiently enriched specific cell population to study disease pathophysiology and to provide a good model for further investigation and drug screening. The differentiation process is very costly and time-consuming, because many specific factors and different culture media must be used. In this study, we used Sedimentation Field Flow Fractionation (SdFFF) to prepare enriched populations derived from hiPSc after only 10 days of culture in a classical medium. Based on phenotypic and proteomic characterization, "hyperlayer" elution resulted in a fraction expressing markers of endothelial progenitors while another fraction expressed markers of neural progenitors. The isolation of subpopulations representing various differentiation lineages is of major interest for the production of specialized, cell-enriched fractions and in the preparation of increasingly complex models for the development of new therapeutic tools.
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Affiliation(s)
| | | | | | | | | | | | | | - Benoît Funalot
- Département de Génétique, CHU Henri-Mondor , F-94000 Créteil, France.,Inserm U955-E10, Université Paris-Est-Créteil, F-94000 Créteil, France
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39
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Shen HC, Wei JY, Chu SY, Chung PC, Hsu TC, Yu HH. Morphogenetic Studies of the Drosophila DA1 Ventral Olfactory Projection Neuron. PLoS One 2016; 11:e0155384. [PMID: 27163287 PMCID: PMC4862648 DOI: 10.1371/journal.pone.0155384] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Accepted: 04/27/2016] [Indexed: 01/04/2023] Open
Abstract
In the Drosophila olfactory system, odorant information is sensed by olfactory sensory neurons and relayed from the primary olfactory center, the antennal lobe (AL), to higher olfactory centers via olfactory projection neurons (PNs). A major portion of the AL is constituted with dendrites of four groups of PNs, anterodorsal PNs (adPNs), lateral PNs (lPNs), lateroventral PNs (lvPNs) and ventral PNs (vPNs). Previous studies have been focused on the development and function of adPNs and lPNs, while the investigation on those of lvPNs and vPNs received less attention. Here, we study the molecular and cellular mechanisms underlying the morphogenesis of a putative male-pheromone responding vPN, the DA1 vPN. Using an intersection strategy to remove background neurons labeled within a DA1 vPN-containing GAL4 line, we depicted morphological changes of the DA1 vPN that occurs at the pupal stage. We then conducted a pilot screen using RNA interference knock-down approach to identify cell surface molecules, including Down syndrome cell adhesion molecule 1 and Semaphorin-1a, that might play essential roles for the DA1 vPN morphogenesis. Taken together, by revealing molecular and cellular basis of the DA1 vPN morphogenesis, we should provide insights into future comprehension of how vPNs are assembled into the olfactory neural circuitry.
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Affiliation(s)
- Hung-Chang Shen
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, Taiwan
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan
| | - Jia-Yi Wei
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, Taiwan
| | - Sao-Yu Chu
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, Taiwan
| | - Pei-Chi Chung
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, Taiwan
| | - Tsai-Chi Hsu
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, Taiwan
| | - Hung-Hsiang Yu
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, Taiwan
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan
- * E-mail:
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Kulkarni A, Ertekin D, Lee CH, Hummel T. Birth order dependent growth cone segregation determines synaptic layer identity in the Drosophila visual system. eLife 2016; 5:e13715. [PMID: 26987017 PMCID: PMC4846375 DOI: 10.7554/elife.13715] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Accepted: 03/16/2016] [Indexed: 12/13/2022] Open
Abstract
The precise recognition of appropriate synaptic partner neurons is a critical step during neural circuit assembly. However, little is known about the developmental context in which recognition specificity is important to establish synaptic contacts. We show that in the Drosophila visual system, sequential segregation of photoreceptor afferents, reflecting their birth order, lead to differential positioning of their growth cones in the early target region. By combining loss- and gain-of-function analyses we demonstrate that relative differences in the expression of the transcription factor Sequoia regulate R cell growth cone segregation. This initial growth cone positioning is consolidated via cell-adhesion molecule Capricious in R8 axons. Further, we show that the initial growth cone positioning determines synaptic layer selection through proximity-based axon-target interactions. Taken together, we demonstrate that birth order dependent pre-patterning of afferent growth cones is an essential pre-requisite for the identification of synaptic partner neurons during visual map formation in Drosophila. DOI:http://dx.doi.org/10.7554/eLife.13715.001 A nervous system requires a precise network of connections between cells called neurons to work properly. Within the brain, the fiber-like connections between pairs of neurons are not running crisscross like a pile of spaghetti. Instead, connected partner neurons are organized into distinct layers and columns. Many questions remain about how these partner neurons find each other and how the layers of fiber-like connections form. To answer these questions, scientists often study the part of the fruit fly nervous system that controls the insect’s vision. This brain-like structure is simple and can be easily manipulated with genetic engineering. Fruit fly studies have helped identify some molecules that play a role in helping partner cells find one another and connect. These studies have also shown that the timing of brain cell development appears to play a role. But the role that layer formation plays in the process is still a mystery. Now, Kulkarni et al. show that the birthdate of neurons in the fruit fly visual system helps organize them into layers. These neurons are generated early in the development of the fly. Shortly after birth, a molecular clock under the control of a protein called Sequoia starts within each newly generated neuron. The Sequoia protein is a transcription factor and controls the activity of many genes, and the molecular clock provides the growing neuron fibers with information about where and when to look for its partner neurons. By manipulating the amount and time that Sequoia is produced in the fly visual system, Kulkarni et al. show that this clock helps arrange the growing cells into layers. Cells with similar birthdates connect and are arranged into layers. How much and when Sequoia is produced dictates where each new layer begins. The next steps for the research will be to learn more about how the clock works and identify any intermediaries between the clock and cell growth patterns. DOI:http://dx.doi.org/10.7554/eLife.13715.002
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Affiliation(s)
| | - Deniz Ertekin
- Department of Neurobiology, University of Vienna, Vienna, Austria
| | - Chi-Hon Lee
- Section on Neuronal Connectivity, Laboratory of Gene Regulation and Development, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, United States
| | - Thomas Hummel
- Department of Neurobiology, University of Vienna, Vienna, Austria
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Luke MPS, LeVatte TL, O'Reilly AM, Smith BJ, Tremblay F, Brown RE, Clarke DB. Effect of NCAM on aged-related deterioration in vision. Neurobiol Aging 2016; 41:93-106. [PMID: 27103522 DOI: 10.1016/j.neurobiolaging.2016.02.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2015] [Revised: 01/22/2016] [Accepted: 02/04/2016] [Indexed: 01/14/2023]
Abstract
The neural cell adhesion molecule (NCAM) is involved in developmental processes and age-associated cognitive decline; however, little is known concerning the effects of NCAM in the visual system during aging. Using anatomical, electrophysiological, and behavioral assays, we analyzed age-related changes in visual function of NCAM deficient (-/-) and wild-type mice. Anatomical analyses indicated that aging NCAM -/- mice had fewer retinal ganglion cells, thinner retinas, and fewer photoreceptor cell layers than age-matched controls. Electroretinogram testing of retinal function in young adult NCAM -/- mice showed a 2-fold increase in a- and b-wave amplitude compared with wild-type mice, but the retinal activity dropped dramatically to control levels when the animals reached 10 months. In behavioral tasks, NCAM -/- mice had no visual pattern discrimination ability and showed premature loss of vision as they aged. Together, these findings demonstrate that NCAM plays significant roles in the adult visual system in establishing normal retinal anatomy, physiology and function, and in maintaining vision during aging.
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Affiliation(s)
- Margaret Po-Shan Luke
- Department of Medical Neuroscience, Life Science Research Institute, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Terry L LeVatte
- Department of Medical Neuroscience, Life Science Research Institute, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Amanda M O'Reilly
- Department of Medical Neuroscience, Life Science Research Institute, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Benjamin J Smith
- Department of Biology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - François Tremblay
- Department of Physiology and Biophysics, Dalhousie University, Halifax, Nova Scotia, Canada; Department of Ophthalmology and Visual Sciences, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Richard E Brown
- Department of Psychology and Neuroscience, Life Science Centre, Dalhousie University, Halifax, Nova Scotia, Canada
| | - David B Clarke
- Department of Medical Neuroscience, Life Science Research Institute, Dalhousie University, Halifax, Nova Scotia, Canada; Department of Surgery (Neurosurgery), Life Science Research Institute, Dalhousie University, Halifax, Nova Scotia, Canada; Department of Medicine (Endocrinology), Life Science Research Institute, Dalhousie University, Halifax, Nova Scotia, Canada; Department of Ophthalmology & Visual Sciences, Life Science Research Institute, Dalhousie University, Halifax, Nova Scotia, Canada.
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Goodhill GJ. Introduction to the Special Issue on From Maps to Circuits: Models and Mechanisms for Generating Neural Connections. Dev Neurobiol 2016; 75:539-41. [PMID: 25649646 DOI: 10.1002/dneu.22270] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Accepted: 01/24/2015] [Indexed: 11/11/2022]
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