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Salas-Lucia F, Escamilla S, Bianco AC, Dumitrescu A, Refetoff S. Impaired T3 uptake and action in MCT8-deficient cerebral organoids underlie Allan-Herndon-Dudley syndrome. JCI Insight 2024; 9:e174645. [PMID: 38376950 PMCID: PMC11128209 DOI: 10.1172/jci.insight.174645] [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: 08/09/2023] [Accepted: 02/15/2024] [Indexed: 02/22/2024] Open
Abstract
Patients with mutations in the thyroid hormone (TH) cell transporter monocarboxylate transporter 8 (MCT8) gene develop severe neuropsychomotor retardation known as Allan-Herndon-Dudley syndrome (AHDS). It is assumed that this is caused by a reduction in TH signaling in the developing brain during both intrauterine and postnatal developmental stages, and treatment remains understandably challenging. Given species differences in brain TH transporters and the limitations of studies in mice, we generated cerebral organoids (COs) using human induced pluripotent stem cells (iPSCs) from MCT8-deficient patients. MCT8-deficient COs exhibited (i) altered early neurodevelopment, resulting in smaller neural rosettes with thinner cortical units, (ii) impaired triiodothyronine (T3) transport in developing neural cells, as assessed through deiodinase-3-mediated T3 catabolism, (iii) reduced expression of genes involved in cerebral cortex development, and (iv) reduced T3 inducibility of TH-regulated genes. In contrast, the TH analogs 3,5-diiodothyropropionic acid and 3,3',5-triiodothyroacetic acid triggered normal responses (induction/repression of T3-responsive genes) in MCT8-deficient COs, constituting proof of concept that lack of T3 transport underlies the pathophysiology of AHDS and demonstrating the clinical potential for TH analogs to be used in treating patients with AHDS. MCT8-deficient COs represent a species-specific relevant preclinical model that can be utilized to screen drugs with potential benefits as personalized therapeutics for patients with AHDS.
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Affiliation(s)
- Federico Salas-Lucia
- Section of Adult and Pediatric Endocrinology, Diabetes and Metabolism, Department of Medicine, The University of Chicago, Chicago, Illinois, USA
| | - Sergio Escamilla
- Instituto de Neurociencias de Alicante, Miguel Hernández-CSIC University, Sant Joan d’Alacant, Alicante, Spain
| | - Antonio C. Bianco
- Section of Adult and Pediatric Endocrinology, Diabetes and Metabolism, Department of Medicine, The University of Chicago, Chicago, Illinois, USA
| | - Alexandra Dumitrescu
- Section of Adult and Pediatric Endocrinology, Diabetes and Metabolism, Department of Medicine, The University of Chicago, Chicago, Illinois, USA
- Committee on Molecular Metabolism and Nutrition
| | - Samuel Refetoff
- Section of Adult and Pediatric Endocrinology, Diabetes and Metabolism, Department of Medicine, The University of Chicago, Chicago, Illinois, USA
- Department of Pediatrics, and Committee on Genetics, The University of Chicago, Chicago, Illinois, USA
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2
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Mingo-Moreno N, Truschow P, Staiger JF, Wagener RJ. Caudally pronounced deficiencies in preplate splitting and migration underly a rostro-caudal progression of cortical lamination defects in the reeler brain. Cereb Cortex 2024; 34:bhae023. [PMID: 38383722 DOI: 10.1093/cercor/bhae023] [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: 01/11/2023] [Revised: 12/30/2023] [Accepted: 12/31/2023] [Indexed: 02/23/2024] Open
Abstract
In mammalian neocortex development, every cohort of newborn neurons is guided toward the marginal zone, leading to an "inside-out" organization of the 6 neocortical layers. This migratory pattern is regulated by the extracellular glycoprotein Reelin. The reeler mouse shows a homozygous mutation of the reelin gene. Using RNA in situ hybridization we could demonstrate that the Reelin-deficient mouse cortex (male and female) displays an increasing lamination defect along the rostro-caudal axis that is characterized by strong cellular intermingling, but roughly reproduces the "inside-out" pattern in rostral cortex, while caudal cortex shows a relative inversion of neuronal positioning ("outside-in"). We found that in development of the reeler cortex, preplate-splitting is also defective with an increasing severity along the rostro-caudal axis. This leads to a misplacement of subplate neurons that are crucial for a switch in migration mode within the cortical plate. Using Flash Tag labeling and nucleoside analog pulse-chasing, we found an according migration defect within the cortical plate, again with a progressive severity along the rostro-caudal axis. Thus, loss of one key player in neocortical development leads to highly area-specific (caudally pronounced) developmental deficiencies that result in multiple roughly opposite rostral versus caudal adult neocortical phenotypes.
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Affiliation(s)
- Nieves Mingo-Moreno
- Institute for Neuroanatomy, University Medical Center Göttingen, Göttingen 37075, Germany
- Center for Nanoscale Microscopy and Molecular Physiology of the Brain, Göttingen 37073, Germany
| | - Pavel Truschow
- Institute for Neuroanatomy, University Medical Center Göttingen, Göttingen 37075, Germany
| | - Jochen F Staiger
- Institute for Neuroanatomy, University Medical Center Göttingen, Göttingen 37075, Germany
- Center for Nanoscale Microscopy and Molecular Physiology of the Brain, Göttingen 37073, Germany
| | - Robin J Wagener
- Institute for Neuroanatomy, University Medical Center Göttingen, Göttingen 37075, Germany
- Department of Neurology, University Hospital Heidelberg, Heidelberg 69120, Germany
- Clinical Cooperation Unit Neurooncology, German Cancer Research Center (DKFZ), Heidelberg 69120, Germany
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3
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Elorriaga V, Pierani A, Causeret F. Cajal-retzius cells: Recent advances in identity and function. Curr Opin Neurobiol 2023; 79:102686. [PMID: 36774666 DOI: 10.1016/j.conb.2023.102686] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Revised: 12/29/2022] [Accepted: 01/08/2023] [Indexed: 02/12/2023]
Abstract
Cajal-Retzius cells (CRs) are a transient neuronal type of the developing cerebral cortex. Over the years, they have been shown or proposed to play important functions in neocortical and hippocampal morphogenesis, circuit formation, brain evolution and human pathology. Because of their short lifespan, CRs have been pictured as a purely developmental cell type, whose production and active elimination are both required for correct brain development. In this review, we present some of the findings that allow us to better appreciate the identity and diversity of this very special cell type, and propose a unified definition of what should be considered a Cajal-Retzius cell, especially when working with non-mammalian species or organoids. In addition, we highlight a flurry of recent studies pointing to the importance of CRs in the assembly of functional and dysfunctional cortical networks.
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Affiliation(s)
- Vicente Elorriaga
- Université Paris Cité, Imagine Institute, Team Genetics and Development of the Cerebral Cortex, F-75015 Paris, France; Université Paris Cité, INSERM U1266, Institute of Psychiatry and Neuroscience of Paris, F-75014 Paris, France
| | - Alessandra Pierani
- Université Paris Cité, Imagine Institute, Team Genetics and Development of the Cerebral Cortex, F-75015 Paris, France; Université Paris Cité, INSERM U1266, Institute of Psychiatry and Neuroscience of Paris, F-75014 Paris, France; GHU-Paris Psychiatrie et Neurosciences, Hôpital Sainte Anne, F-75014 Paris, France.
| | - Frédéric Causeret
- Université Paris Cité, Imagine Institute, Team Genetics and Development of the Cerebral Cortex, F-75015 Paris, France; Université Paris Cité, INSERM U1266, Institute of Psychiatry and Neuroscience of Paris, F-75014 Paris, France.
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4
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Merkulyeva N, Mikhalkin А, Kostareva A, Vavilova T. Transient neurochemical features of the perigeniculate neurons during early postnatal development of the cat. J Comp Neurol 2022; 530:3193-3208. [PMID: 36036192 DOI: 10.1002/cne.25402] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 08/09/2022] [Accepted: 08/11/2022] [Indexed: 11/07/2022]
Abstract
The thalamic reticular nucleus receives axons from the thalamic sensory nuclei and the cerebral cortex. The visual part of this nucleus in carnivores is the perigeniculate nucleus located dorsal to the lateral geniculate nucleus. The perigeniculate nucleus participates in the modulation of visual processing and in the transition of synchronized slow rhythmicity during sleep into desynchronized high-frequency activity during arousal and consists of inhibitory neurons. The main neurochemical markers for perigeniculate neurons are glutamic acid decarboxylase and Ca2+ -binding protein parvalbumin. Previous studies of postnatal development focused on the morphological features of the perigeniculate nucleus; however, its neurochemistry remains poorly understood. In this study, we focused on the postnatal development of perigeniculate neurons using immunohistochemical labeling of parvalbumin, two related Ca2+ -binding proteins (calretinin and calbindin), glutamic acid decarboxylase, and a common neuronal protein, NeuN, in kittens that were 0-123 days old and in adult cats. In parallel with the well-known dominant neuronal populations expressing parvalbumin and GAD67 and persisting until adulthood, transient populations expressing calretinin and calbindin were observed. The calbindin-positive neurons were similar to the main perigeniculate population and showed close morphological features and parvalbumin coexpression. In contrast, the calretinin-positive neurons differed in their morphological characteristics and did not express GAD67, thus distinguishing them from the majority of perigeniculate neurons. A possible link between these populations was revealed, and the development of thalamocortical processing is discussed.
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Affiliation(s)
- Natalia Merkulyeva
- Lab Neuromorphology, Pavlov Institute of Physiology RAS, Saint-Petersburg, Russia
| | - Аleksandr Mikhalkin
- Lab Neuromorphology, Pavlov Institute of Physiology RAS, Saint-Petersburg, Russia
| | - Anna Kostareva
- Institution of Molecular Biology and Genetics, Almazov National Medical Research Centre, Saint-Petersburg, Russia
| | - Tatyana Vavilova
- Institution of Molecular Biology and Genetics, Almazov National Medical Research Centre, Saint-Petersburg, Russia
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5
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López-Mengual A, Segura-Feliu M, Sunyer R, Sanz-Fraile H, Otero J, Mesquida-Veny F, Gil V, Hervera A, Ferrer I, Soriano J, Trepat X, Farré R, Navajas D, Del Río JA. Involvement of Mechanical Cues in the Migration of Cajal-Retzius Cells in the Marginal Zone During Neocortical Development. Front Cell Dev Biol 2022; 10:886110. [PMID: 35652101 PMCID: PMC9150848 DOI: 10.3389/fcell.2022.886110] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 04/25/2022] [Indexed: 12/24/2022] Open
Abstract
Emerging evidence points to coordinated action of chemical and mechanical cues during brain development. At early stages of neocortical development, angiogenic factors and chemokines such as CXCL12, ephrins, and semaphorins assume crucial roles in orchestrating neuronal migration and axon elongation of postmitotic neurons. Here we explore the intrinsic mechanical properties of the developing marginal zone of the pallium in the migratory pathways and brain distribution of the pioneer Cajal-Retzius cells. These neurons are generated in several proliferative regions in the developing brain (e.g., the cortical hem and the pallial subpallial boundary) and migrate tangentially in the preplate/marginal zone covering the upper portion of the developing cortex. These cells play crucial roles in correct neocortical layer formation by secreting several molecules such as Reelin. Our results indicate that the motogenic properties of Cajal-Retzius cells and their perinatal distribution in the marginal zone are modulated by both chemical and mechanical factors, by the specific mechanical properties of Cajal-Retzius cells, and by the differential stiffness of the migratory routes. Indeed, cells originating in the cortical hem display higher migratory capacities than those generated in the pallial subpallial boundary which may be involved in the differential distribution of these cells in the dorsal-lateral axis in the developing marginal zone.
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Affiliation(s)
- Ana López-Mengual
- Molecular and Cellular Neurobiotechnology, Institute for Bioengineering of Catalonia (IBEC), Barcelona, Spain.,Department of Cell Biology, Physiology and Immunology, Universitat de Barcelona, Barcelona, Spain.,Network Centre of Biomedical Research of Neurodegenerative Diseases (CIBERNED), Institute of Health Carlos III, Madrid, Spain.,Institute of Neuroscience, University of Barcelona, Barcelona, Spain
| | - Miriam Segura-Feliu
- Molecular and Cellular Neurobiotechnology, Institute for Bioengineering of Catalonia (IBEC), Barcelona, Spain.,Department of Cell Biology, Physiology and Immunology, Universitat de Barcelona, Barcelona, Spain.,Network Centre of Biomedical Research of Neurodegenerative Diseases (CIBERNED), Institute of Health Carlos III, Madrid, Spain.,Institute of Neuroscience, University of Barcelona, Barcelona, Spain
| | - Raimon Sunyer
- Unitat de Biofísica I Bioenginyeria, Universitat de Barcelona, Barcelona, Spain
| | - Héctor Sanz-Fraile
- Unitat de Biofísica I Bioenginyeria, Universitat de Barcelona, Barcelona, Spain
| | - Jorge Otero
- Unitat de Biofísica I Bioenginyeria, Universitat de Barcelona, Barcelona, Spain.,Centro de Investigación Biomédica en Red en Enfermedades Respiratorias, Madrid, Spain
| | - Francina Mesquida-Veny
- Molecular and Cellular Neurobiotechnology, Institute for Bioengineering of Catalonia (IBEC), Barcelona, Spain.,Department of Cell Biology, Physiology and Immunology, Universitat de Barcelona, Barcelona, Spain.,Network Centre of Biomedical Research of Neurodegenerative Diseases (CIBERNED), Institute of Health Carlos III, Madrid, Spain.,Institute of Neuroscience, University of Barcelona, Barcelona, Spain
| | - Vanessa Gil
- Molecular and Cellular Neurobiotechnology, Institute for Bioengineering of Catalonia (IBEC), Barcelona, Spain.,Department of Cell Biology, Physiology and Immunology, Universitat de Barcelona, Barcelona, Spain.,Network Centre of Biomedical Research of Neurodegenerative Diseases (CIBERNED), Institute of Health Carlos III, Madrid, Spain.,Institute of Neuroscience, University of Barcelona, Barcelona, Spain
| | - Arnau Hervera
- Molecular and Cellular Neurobiotechnology, Institute for Bioengineering of Catalonia (IBEC), Barcelona, Spain.,Department of Cell Biology, Physiology and Immunology, Universitat de Barcelona, Barcelona, Spain.,Network Centre of Biomedical Research of Neurodegenerative Diseases (CIBERNED), Institute of Health Carlos III, Madrid, Spain.,Institute of Neuroscience, University of Barcelona, Barcelona, Spain
| | - Isidre Ferrer
- Institute of Neuroscience, University of Barcelona, Barcelona, Spain.,Senior Consultant, Bellvitge University Hospital, Hospitalet de Llobregat, Barcelona, Spain.,Department of Pathology and Experimental Therapeutics, University of Barcelona, Barcelona, Spain
| | - Jordi Soriano
- Departament de Física de La Matèria Condensada, Universitat de Barcelona, Barcelona, Spain.,University of Barcelona Institute of Complex Systems (UBICS), Barcelona, Spain
| | - Xavier Trepat
- Unitat de Biofísica I Bioenginyeria, Universitat de Barcelona, Barcelona, Spain.,Integrative Cell and Tissue Dynamics, Institute for Bioengineering of Catalonia (IBEC), Parc Científic de Barcelona, Barcelona, Spain.,Center for Networked Biomedical Research on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Madrid, Spain.,Institució Catalana de Recerca I Estudis Avançats, University of Barcelona, Barcelona, Spain
| | - Ramon Farré
- Unitat de Biofísica I Bioenginyeria, Universitat de Barcelona, Barcelona, Spain.,Centro de Investigación Biomédica en Red en Enfermedades Respiratorias, Madrid, Spain.,Institut D'Investigacions Biomèdiques August Pi Sunyer, Barcelona, Spain
| | - Daniel Navajas
- Unitat de Biofísica I Bioenginyeria, Universitat de Barcelona, Barcelona, Spain.,Centro de Investigación Biomédica en Red en Enfermedades Respiratorias, Madrid, Spain.,Cellular and Respiratory Biomechanics, Institute for Bioengineering of Catalonia (IBEC), Barcelona, Spain
| | - José Antonio Del Río
- Molecular and Cellular Neurobiotechnology, Institute for Bioengineering of Catalonia (IBEC), Barcelona, Spain.,Department of Cell Biology, Physiology and Immunology, Universitat de Barcelona, Barcelona, Spain.,Network Centre of Biomedical Research of Neurodegenerative Diseases (CIBERNED), Institute of Health Carlos III, Madrid, Spain.,Institute of Neuroscience, University of Barcelona, Barcelona, Spain
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6
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Ignatius E, Puosi R, Palomäki M, Forsbom N, Pohjanpelto M, Alitalo T, Anttonen AK, Avela K, Haataja L, Carroll CJ, Lönnqvist T, Isohanni P. Duplication/triplication mosaicism of EBF3 and expansion of the EBF3 neurodevelopmental disorder phenotype. Eur J Paediatr Neurol 2022; 37:1-7. [PMID: 34999443 DOI: 10.1016/j.ejpn.2021.12.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Revised: 12/06/2021] [Accepted: 12/18/2021] [Indexed: 11/15/2022]
Abstract
Deleterious variants in the transcription factor early B-cell factor 3 (EBF3) are known to cause a neurodevelopmental disorder (EBF3-NDD). We report eleven individuals with EBF3 variants, including an individual with a duplication/triplication mosaicism of a region encompassing EBF3 and a phenotype consistent with EBF3-NDD, which may reflect the importance of EBF3 gene-dosage for neurodevelopment. The phenotype of individuals in this cohort was quite mild compared to the core phenotype of previously described individuals. Although ataxia tended to wane with age, we show that cognitive difficulties may increase, and we recommend that individuals with EBF3-NDD have systematic neuropsychological follow-up.
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Affiliation(s)
- Erika Ignatius
- Department of Child Neurology, Children's Hospital, Pediatric Research Center, University of Helsinki and Helsinki University Hospital, Helsinki, Finland; Research Programs Unit, Stem Cells and Metabolism, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Riina Puosi
- Department of Child Neurology, Children's Hospital, Pediatric Research Center, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Maarit Palomäki
- Department of Radiology, HUS Medical Imaging Center, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Noora Forsbom
- Department of Ophthalmology, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Max Pohjanpelto
- Research Programs Unit, Stem Cells and Metabolism, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Tiina Alitalo
- Laboratory of Genetics, HUS Diagnostic Center, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Anna-Kaisa Anttonen
- Laboratory of Genetics, HUS Diagnostic Center, University of Helsinki and Helsinki University Hospital, Helsinki, Finland; Department of Clinical Genetics, HUS Diagnostic Center, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Kristiina Avela
- Department of Clinical Genetics, HUS Diagnostic Center, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Leena Haataja
- Department of Child Neurology, Children's Hospital, Pediatric Research Center, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Christopher J Carroll
- Genetics Research Centre, Molecular and Clinical Sciences Research Institute, St. George's, University of London, London, United Kingdom
| | - Tuula Lönnqvist
- Department of Child Neurology, Children's Hospital, Pediatric Research Center, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Pirjo Isohanni
- Department of Child Neurology, Children's Hospital, Pediatric Research Center, University of Helsinki and Helsinki University Hospital, Helsinki, Finland; Research Programs Unit, Stem Cells and Metabolism, Faculty of Medicine, University of Helsinki, Helsinki, Finland.
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7
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Nelson MM, Hoff JD, Zeese ML, Corfas G. Poly (ADP-Ribose) Polymerase 1 Regulates Cajal-Retzius Cell Development and Neural Precursor Cell Adhesion. Front Cell Dev Biol 2021; 9:693595. [PMID: 34708032 PMCID: PMC8542860 DOI: 10.3389/fcell.2021.693595] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2021] [Accepted: 09/16/2021] [Indexed: 11/13/2022] Open
Abstract
Poly (ADP-ribose) polymerase 1 (PARP1) is a ubiquitously expressed enzyme that regulates DNA damage repair, cell death, inflammation, and transcription. PARP1 functions by adding ADP-ribose polymers (PAR) to proteins including itself, using NAD+ as a donor. This post-translational modification known as PARylation results in changes in the activity of PARP1 and its substrate proteins and has been linked to the pathogenesis of various neurological diseases. PARP1 KO mice display schizophrenia-like behaviors, have impaired memory formation, and have defects in neuronal proliferation and survival, while mutations in genes that affect PARylation have been associated with intellectual disability, psychosis, neurodegeneration, and stroke in humans. Yet, the roles of PARP1 in brain development have not been extensively studied. We now find that loss of PARP1 leads to defects in brain development and increased neuronal density at birth. We further demonstrate that PARP1 loss increases the expression levels of genes associated with neuronal migration and adhesion in the E15.5 cerebral cortex, including Reln. This correlates with an increased number of Cajal–Retzius (CR) cells in vivo and in cultures of embryonic neural progenitor cells (NPCs) derived from the PARP1 KO cortex. Furthermore, PARP1 loss leads to increased NPC adhesion to N-cadherin, like that induced by experimental exposure to Reelin. Taken together, these results uncover a novel role for PARP1 in brain development, i.e., regulation of CR cells, neuronal density, and cell adhesion.
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Affiliation(s)
- Megan M Nelson
- Kresge Hearing Research Institute and Department of Otolaryngology - Head and Neck Surgery, University of Michigan, Ann Arbor, MI, United States.,Neuroscience Graduate Program, University of Michigan, Ann Arbor, MI, United States
| | - J Damon Hoff
- Single Molecule Analysis in Real-Time Center, Department of Biophysics, University of Michigan, Ann Arbor, MI, United States
| | - Mya L Zeese
- Kresge Hearing Research Institute and Department of Otolaryngology - Head and Neck Surgery, University of Michigan, Ann Arbor, MI, United States.,Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, United States
| | - Gabriel Corfas
- Kresge Hearing Research Institute and Department of Otolaryngology - Head and Neck Surgery, University of Michigan, Ann Arbor, MI, United States.,Neuroscience Graduate Program, University of Michigan, Ann Arbor, MI, United States
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8
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Jiménez S, Moreno N. Analysis of the Expression Pattern of Cajal-Retzius Cell Markers in the Xenopus laevis Forebrain. BRAIN, BEHAVIOR AND EVOLUTION 2021; 96:263-282. [PMID: 34614492 DOI: 10.1159/000519025] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 08/09/2021] [Indexed: 01/26/2023]
Abstract
Cajal-Retzius cells are essential for cortical development in mammals, and their involvement in the evolution of this structure has been widely postulated, but very little is known about their progenitor domains in non-mammalian vertebrates. Using in situhybridization and immunofluorescence techniques we analyzed the expression of some of the main Cajal-Retzius cell markers such as Dbx1, Ebf3, ER81, Lhx1, Lhx5, p73, Reelin, Wnt3a, Zic1, and Zic2 in the forebrain of the anuran Xenopus laevis, because amphibians are the only class of anamniote tetrapods and show a tetrapartite evaginated pallium, but no layered or nuclear organization. Our results suggested that the Cajal-Retzius cell progenitor domains were comparable to those previously described in amniotes. Thus, at dorsomedial telencephalic portions a region comparable to the cortical hem was defined in Xenopus based on the expression of Wnt3a, p73, Reelin, Zic1, and Zic2. In the septum, two different domains were observed: a periventricular dorsal septum, at the limit between the pallium and the subpallium, expressing Reelin, Zic1, and Zic2, and a related septal domain, expressing Ebf3, Zic1, and Zic2. In the lateral telencephalon, the ventral pallium next to the pallio-subpallial boundary, the lack of Dbx1 and the unique expression of Reelin during development defined this territory as the most divergent with respect to mammals. Finally, we also analyzed the expression of these markers at the prethalamic eminence region, suggested as Cajal-Retzius progenitor domain in amniotes, observing there Zic1, Zic2, ER81, and Lhx1 expression. Our data show that in anurans there are different subtypes and progenitor domains of Cajal-Retzius cells, which probably contribute to the cortical regional specification and territory-specific properties. This supports the notion that the basic organization of pallial derivatives in vertebrates follows a comparable fundamental arrangement, even in those that do not have a sophisticated stratified cortical structure like the mammalian cerebral cortex.
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Affiliation(s)
- Sara Jiménez
- Department of Cell Biology, Faculty of Biology, University Complutense, Madrid, Spain
| | - Nerea Moreno
- Department of Cell Biology, Faculty of Biology, University Complutense, Madrid, Spain
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9
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Huang Y, Mei L, Wang Y, Ye H, Ma X, Zhang J, Cai M, Li P, Ge Y, Zhou Y. A Novel de novo Mutation in EBF3 Associated With Hypotonia, Ataxia, and Delayed Development Syndrome in a Chinese Boy. Front Genet 2021; 12:676832. [PMID: 34367240 PMCID: PMC8339956 DOI: 10.3389/fgene.2021.676832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2021] [Accepted: 07/05/2021] [Indexed: 11/13/2022] Open
Abstract
Objective Global developmental delay has markedly high phenotypic and genetic heterogeneity, and is a great challenge for clinical diagnosis. Hypotonia, ataxia, and delayed development syndrome (HADDS), first reported in 2017, is one type of global development delay. The aim of the present study was to investigate the genetic etiology of a Chinese boy with global developmental delay. Methods We combined clinical and imaging phenotyping with trio whole-exome sequencing and Sanger sequencing to the patient and his clinically unaffected parents. A luciferase reporter and immunofluorescence were performed to detect the effect of mutation on transcriptional activity and subcellular localization. Results The patient presented with several previously unreported symptoms in the patients with HADDS, including hemangiomas, mild hearing abnormalities and tracheomalacia. A novel EBF3 c.589A > G missense mutation (p.Asn197Asp, p.N197D) was identified in the patient but not in his parents. By constructing the plasmid and transfecting HEK293T cells, EBF3-N197D mutant showed impaired activation of luciferase reporter expression of the p21 promoter, and the mutant affected its entry into the nucleus. Conclusion To the best of our knowledge, this is the first report of EBF3 pathogenic mutation which associated with HADDS in the Chinese population. Our results expand the phenotypes and pathogenic mutation spectrum of HADDS, thus potentially facilitating the clinical diagnosis and genetic counseling of HADDS patients.
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Affiliation(s)
- Yanru Huang
- Women and Children's Hospital, School of Medicine, Xiamen University, Xiamen, China.,United Diagnostic and Research Center for Clinical Genetics, School of Public Health, Xiamen University, Xiamen, China.,Xiamen Key Laboratory of Reproduction and Genetics, Xiamen, China
| | - Libin Mei
- Women and Children's Hospital, School of Medicine, Xiamen University, Xiamen, China.,United Diagnostic and Research Center for Clinical Genetics, School of Public Health, Xiamen University, Xiamen, China.,Xiamen Key Laboratory of Reproduction and Genetics, Xiamen, China
| | - Yangdan Wang
- Women and Children's Hospital, School of Medicine, Xiamen University, Xiamen, China
| | - Huiming Ye
- Women and Children's Hospital, School of Medicine, Xiamen University, Xiamen, China.,United Diagnostic and Research Center for Clinical Genetics, School of Public Health, Xiamen University, Xiamen, China
| | - Xiaomin Ma
- Women and Children's Hospital, School of Medicine, Xiamen University, Xiamen, China
| | - Jian Zhang
- Women and Children's Hospital, School of Medicine, Xiamen University, Xiamen, China
| | - Meijiao Cai
- Women and Children's Hospital, School of Medicine, Xiamen University, Xiamen, China
| | - Ping Li
- Women and Children's Hospital, School of Medicine, Xiamen University, Xiamen, China.,Xiamen Key Laboratory of Reproduction and Genetics, Xiamen, China
| | - Yunsheng Ge
- Women and Children's Hospital, School of Medicine, Xiamen University, Xiamen, China
| | - Yulin Zhou
- Women and Children's Hospital, School of Medicine, Xiamen University, Xiamen, China.,United Diagnostic and Research Center for Clinical Genetics, School of Public Health, Xiamen University, Xiamen, China
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10
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Moreau MX, Saillour Y, Cwetsch AW, Pierani A, Causeret F. Single-cell transcriptomics of the early developing mouse cerebral cortex disentangle the spatial and temporal components of neuronal fate acquisition. Development 2021; 148:269283. [PMID: 34170322 DOI: 10.1242/dev.197962] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2020] [Accepted: 06/21/2021] [Indexed: 01/01/2023]
Abstract
In the developing cerebral cortex, how progenitors that seemingly display limited diversity end up producing a vast array of neurons remains a puzzling question. The prevailing model suggests that temporal maturation of progenitors is a key driver in the diversification of the neuronal output. However, temporal constraints are unlikely to account for all diversity, especially in the ventral and lateral pallium where neuronal types significantly differ from their dorsal neocortical counterparts born at the same time. In this study, we implemented single-cell RNAseq to sample the diversity of progenitors and neurons along the dorso-ventral axis of the early developing pallium. We first identified neuronal types, mapped them on the tissue and determined their origin through genetic tracing. We characterised progenitor diversity and disentangled the gene modules underlying temporal versus spatial regulations of neuronal specification. Finally, we reconstructed the developmental trajectories followed by ventral and dorsal pallial neurons to identify lineage-specific gene waves. Our data suggest a model by which discrete neuronal fate acquisition from a continuous gradient of progenitors results from the superimposition of spatial information and temporal maturation.
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Affiliation(s)
- Matthieu X Moreau
- Université de Paris, Imagine Institute, Team Genetics and Development of the Cerebral Cortex, F-75015, Paris, France.,Université de Paris, Institute of Psychiatry and Neuroscience of Paris, INSERM U1266, F-75014, Paris, France
| | - Yoann Saillour
- Université de Paris, Imagine Institute, Team Genetics and Development of the Cerebral Cortex, F-75015, Paris, France.,Université de Paris, Institute of Psychiatry and Neuroscience of Paris, INSERM U1266, F-75014, Paris, France
| | - Andrzej W Cwetsch
- Université de Paris, Imagine Institute, Team Genetics and Development of the Cerebral Cortex, F-75015, Paris, France.,Université de Paris, Institute of Psychiatry and Neuroscience of Paris, INSERM U1266, F-75014, Paris, France
| | - Alessandra Pierani
- Université de Paris, Imagine Institute, Team Genetics and Development of the Cerebral Cortex, F-75015, Paris, France.,Université de Paris, Institute of Psychiatry and Neuroscience of Paris, INSERM U1266, F-75014, Paris, France
| | - Frédéric Causeret
- Université de Paris, Imagine Institute, Team Genetics and Development of the Cerebral Cortex, F-75015, Paris, France.,Université de Paris, Institute of Psychiatry and Neuroscience of Paris, INSERM U1266, F-75014, Paris, France
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11
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Bedogni F, Hevner RF. Cell-Type-Specific Gene Expression in Developing Mouse Neocortex: Intermediate Progenitors Implicated in Axon Development. Front Mol Neurosci 2021; 14:686034. [PMID: 34321999 PMCID: PMC8313239 DOI: 10.3389/fnmol.2021.686034] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Accepted: 06/03/2021] [Indexed: 01/06/2023] Open
Abstract
Cerebral cortex projection neurons (PNs) are generated from intermediate progenitors (IPs), which are in turn derived from radial glial progenitors (RGPs). To investigate developmental processes in IPs, we profiled IP transcriptomes in embryonic mouse neocortex, using transgenic Tbr2-GFP mice, cell sorting, and microarrays. These data were used in combination with in situ hybridization to ascertain gene sets specific for IPs, RGPs, PNs, interneurons, and other neural and non-neural cell types. RGP-selective transcripts (n = 419) included molecules for Notch receptor signaling, proliferation, neural stem cell identity, apical junctions, necroptosis, hippo pathway, and NF-κB pathway. RGPs also expressed specific genes for critical interactions with meningeal and vascular cells. In contrast, IP-selective genes (n = 136) encoded molecules for activated Delta ligand presentation, epithelial-mesenchymal transition, core planar cell polarity (PCP), axon genesis, and intrinsic excitability. Interestingly, IPs expressed several “dependence receptors” (Unc5d, Dcc, Ntrk3, and Epha4) that induce apoptosis in the absence of ligand, suggesting a competitive mechanism for IPs and new PNs to detect key environmental cues or die. Overall, our results imply a novel role for IPs in the patterning of neuronal polarization, axon differentiation, and intrinsic excitability prior to mitosis. Significantly, IPs highly express Wnt-PCP, netrin, and semaphorin pathway molecules known to regulate axon polarization in other systems. In sum, IPs not only amplify neurogenesis quantitatively, but also molecularly “prime” new PNs for axogenesis, guidance, and excitability.
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Affiliation(s)
| | - Robert F Hevner
- Department of Pathology, University of California, San Diego, La Jolla, CA, United States
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12
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Causeret F, Moreau MX, Pierani A, Blanquie O. The multiple facets of Cajal-Retzius neurons. Development 2021; 148:268379. [PMID: 34047341 DOI: 10.1242/dev.199409] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Cajal-Retzius neurons (CRs) are among the first-born neurons in the developing cortex of reptiles, birds and mammals, including humans. The peculiarity of CRs lies in the fact they are initially embedded into the immature neuronal network before being almost completely eliminated by cell death at the end of cortical development. CRs are best known for controlling the migration of glutamatergic neurons and the formation of cortical layers through the secretion of the glycoprotein reelin. However, they have been shown to play numerous additional key roles at many steps of cortical development, spanning from patterning and sizing functional areas to synaptogenesis. The use of genetic lineage tracing has allowed the discovery of their multiple ontogenetic origins, migratory routes, expression of molecular markers and death dynamics. Nowadays, single-cell technologies enable us to appreciate the molecular heterogeneity of CRs with an unprecedented resolution. In this Review, we discuss the morphological, electrophysiological, molecular and genetic criteria allowing the identification of CRs. We further expose the various sources, migration trajectories, developmental functions and death dynamics of CRs. Finally, we demonstrate how the analysis of public transcriptomic datasets allows extraction of the molecular signature of CRs throughout their transient life and consider their heterogeneity within and across species.
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Affiliation(s)
- Frédéric Causeret
- Université de Paris, Imagine Institute, Team Genetics and Development of the Cerebral Cortex, F-75015 Paris, France.,Université de Paris, Institute of Psychiatry and Neuroscience of Paris, INSERM U1266, F-75014 Paris, France
| | - Matthieu X Moreau
- Université de Paris, Imagine Institute, Team Genetics and Development of the Cerebral Cortex, F-75015 Paris, France.,Université de Paris, Institute of Psychiatry and Neuroscience of Paris, INSERM U1266, F-75014 Paris, France
| | - Alessandra Pierani
- Université de Paris, Imagine Institute, Team Genetics and Development of the Cerebral Cortex, F-75015 Paris, France.,Université de Paris, Institute of Psychiatry and Neuroscience of Paris, INSERM U1266, F-75014 Paris, France.,Groupe Hospitalier Universitaire Paris Psychiatrie et Neurosciences, F-75014 Paris, France
| | - Oriane Blanquie
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University Mainz, D-55128 Mainz, Germany
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13
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Gilardi C, Kalebic N. The Ferret as a Model System for Neocortex Development and Evolution. Front Cell Dev Biol 2021; 9:661759. [PMID: 33996819 PMCID: PMC8118648 DOI: 10.3389/fcell.2021.661759] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Accepted: 04/01/2021] [Indexed: 12/19/2022] Open
Abstract
The neocortex is the largest part of the cerebral cortex and a key structure involved in human behavior and cognition. Comparison of neocortex development across mammals reveals that the proliferative capacity of neural stem and progenitor cells and the length of the neurogenic period are essential for regulating neocortex size and complexity, which in turn are thought to be instrumental for the increased cognitive abilities in humans. The domesticated ferret, Mustela putorius furo, is an important animal model in neurodevelopment for its complex postnatal cortical folding, its long period of forebrain development and its accessibility to genetic manipulation in vivo. Here, we discuss the molecular, cellular, and histological features that make this small gyrencephalic carnivore a suitable animal model to study the physiological and pathological mechanisms for the development of an expanded neocortex. We particularly focus on the mechanisms of neural stem cell proliferation, neuronal differentiation, cortical folding, visual system development, and neurodevelopmental pathologies. We further discuss the technological advances that have enabled the genetic manipulation of the ferret in vivo. Finally, we compare the features of neocortex development in the ferret with those of other model organisms.
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14
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Jiménez de la Peña M, Jiménez de Domingo A, Tirado P, Calleja-Pérez B, Alcaraz LA, Álvarez S, Williams J, Hagman JR, Németh AH, Fernández-Jaén A. Neuroimaging Findings in Patients with EBF3 Mutations: Report of Two Cases. Mol Syndromol 2021; 12:186-193. [PMID: 34177436 DOI: 10.1159/000513583] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Accepted: 12/03/2020] [Indexed: 12/27/2022] Open
Abstract
Early B cell factor 3 (EBF3) is a transcription factor involved in brain development. Heterozygous, loss-of-function mutations in EBF3 have been reported in an autosomal dominant neurodevelopmental syndrome characterized by hypotonia, ataxia, and developmental delay (sometimes described as "HADD"s). We report 2 unrelated cases with novel de novo EBF3 mutations: c.455G>T (p.Arg152Leu) and c.962dup (p.Tyr321*) to expand the genotype/phenotype correlations of this disorder; clinical, neuropsychological, and MRI studies were used to define the phenotype. IQ was in the normal range and diffusion tensor imaging revealed asymmetric alterations of the longitudinal fasciculus in both cases. Our results demonstrate that EBF3 mutations can underlie neurodevelopmental disorders without intellectual disability. Long tract abnormalities have not been previously recognized and suggest that they may be an unrecognized and characteristic feature in this syndrome.
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Affiliation(s)
| | | | - Pilar Tirado
- Department of Pediatric Neurology, Hospital Universitario La Paz, Madrid, Spain
| | | | | | - Sara Álvarez
- Genomics and Medicine, NIMGenetics, Madrid, Spain
| | - Jonathan Williams
- Oxford Medical Genetics Laboratories, Churchill Hospital, Oxford, United Kingdom
| | - James R Hagman
- Department of Immunology and Genomic Medicine, National Jewish Health, Denver, Colorado, USA
| | - Andrea H Németh
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom.,Oxford Centre for Genomic Medicine, Oxford University Hospitals NHS Foundation Trust, Oxford, United Kingdom
| | - Alberto Fernández-Jaén
- Department of Pediatric Neurology, Hospital Universitario Quirónsalud, and Medicine School, Universidad Europea de Madrid, Madrid, Spain
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15
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Li J, Sun L, Peng XL, Yu XM, Qi SJ, Lu ZJ, Han JDJ, Shen Q. Integrative genomic analysis of early neurogenesis reveals a temporal genetic program for differentiation and specification of preplate and Cajal-Retzius neurons. PLoS Genet 2021; 17:e1009355. [PMID: 33760820 PMCID: PMC7990179 DOI: 10.1371/journal.pgen.1009355] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Accepted: 01/12/2021] [Indexed: 01/02/2023] Open
Abstract
Neurogenesis in the developing neocortex begins with the generation of the preplate, which consists of early-born neurons including Cajal-Retzius (CR) cells and subplate neurons. Here, utilizing the Ebf2-EGFP transgenic mouse in which EGFP initially labels the preplate neurons then persists in CR cells, we reveal the dynamic transcriptome profiles of early neurogenesis and CR cell differentiation. Genome-wide RNA-seq and ChIP-seq analyses at multiple early neurogenic stages have revealed the temporal gene expression dynamics of early neurogenesis and distinct histone modification patterns in early differentiating neurons. We have identified a new set of coding genes and lncRNAs involved in early neuronal differentiation and validated with functional assays in vitro and in vivo. In addition, at E15.5 when Ebf2-EGFP+ cells are mostly CR neurons, single-cell sequencing analysis of purified Ebf2-EGFP+ cells uncovers molecular heterogeneities in CR neurons, but without apparent clustering of cells with distinct regional origins. Along a pseudotemporal trajectory these cells are classified into three different developing states, revealing genetic cascades from early generic neuronal differentiation to late fate specification during the establishment of CR neuron identity and function. Our findings shed light on the molecular mechanisms governing the early differentiation steps during cortical development, especially CR neuron differentiation. Neural stem cells and progenitor cells in the embryonic brain give rise to neurons following a precise temporal order after initial expansion. Early-born neurons including Cajal-Retzius (CR) cells and subplate neurons form the preplate in the developing cerebral cortex, then CR neurons occupy the layer 1, playing an important role in cortical histogenesis. The molecular mechanisms governing the early neuronal differentiation processes remain to be explored. Here, by genome-wide approaches including bulk RNA-seq, single-cell RNA-seq and ChIP-seq, we comprehensively characterized the temporal dynamic gene expression profile and epigenetic status at different stages during early cortical development and uncovered molecularly heterogeneous subpopulations within the CR cells. We revealed CR neuron signatures and cell type-specific histone modification patterns along early neuron specification. Using in vitro and in vivo assays, we identified novel lncRNAs as potential functional regulators in preplate differentiation and CR neuron identity establishment. Our study provides a comprehensive analysis of the genetic and epigenetic programs during neuronal differentiation and would help bring new insights into the early cortical neurogenesis process, particularly the differentiation of CR neurons.
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Affiliation(s)
- Jia Li
- Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration of Ministry of Education, Orthopaedic Department of Tongji Hospital, School of Life Sciences and Technology, Tongji University, Shanghai, China
- PTN graduate program, School of Life Sciences, Peking University, Beijing, China
- School of Medicine, Tsinghua University, Beijing, China
| | - Lei Sun
- PTN graduate program, School of Life Sciences, Tsinghua University, Beijing, China
| | | | - Xiao-Ming Yu
- School of Medicine, Tsinghua University, Beijing, China
| | - Shao-Jun Qi
- Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration of Ministry of Education, Orthopaedic Department of Tongji Hospital, School of Life Sciences and Technology, Tongji University, Shanghai, China
- School of Medicine, Tsinghua University, Beijing, China
| | - Zhi John Lu
- MOE Key Laboratory of Bioinformatics, Center for Synthetic and Systems Biology, School of Life Sciences, Tsinghua University, Beijing, China
| | - Jing-Dong J. Han
- Key Laboratory of Computational Biology, CAS Center for Excellence in Molecular Cell Science, Collaborative Innovation Center for Genetics and Developmental Biology, Chinese Academy of Sciences-Max Planck Partner Institute for Computational Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Qin Shen
- Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration of Ministry of Education, Orthopaedic Department of Tongji Hospital, School of Life Sciences and Technology, Tongji University, Shanghai, China
- Frontier Science Center for Stem Cell Research, Ministry of Education, School of Life Sciences and Technology, Tongji University, Shanghai, China
- Brain and Spinal Cord Clinical Research Center, Tongji University, Shanghai, China
- * E-mail:
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16
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A Toolbox of Criteria for Distinguishing Cajal-Retzius Cells from Other Neuronal Types in the Postnatal Mouse Hippocampus. eNeuro 2020; 7:ENEURO.0516-19.2019. [PMID: 31907212 PMCID: PMC7004485 DOI: 10.1523/eneuro.0516-19.2019] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Accepted: 12/12/2019] [Indexed: 01/05/2023] Open
Abstract
The study of brain circuits depends on a clear understanding of the role played by different neuronal populations. Therefore, the unambiguous identification of different cell types is essential for the correct interpretation of experimental data. Here, we emphasize to the broader neuroscience community the importance of recognizing the persistent presence of Cajal-Retzius cells in the molecular layers of the postnatal hippocampus, and then we suggest a variety of criteria for distinguishing Cajal-Retzius cells from other neurons of the hippocampal molecular layers, such as GABAergic interneurons and semilunar granule cells. The toolbox of criteria that we have investigated (in male and female mice) can be useful both for anatomical and functional experiments, and relies on the quantitative study of neuronal somatic/nuclear morphology, location and developmental profile, expression of specific molecular markers (GAD67, reelin, COUP-TFII, calretinin, and p73), single cell anatomy, and electrophysiological properties. We conclude that Cajal-Retzius cells are small, non-GABAergic neurons that are tightly associated with the hippocampal fissure (HF), and that, within this area of interest, selectively express the proteins p73 and calretinin. We highlight the dangers of using markers such as reelin or COUP-TFII to identify Cajal-Retzius cells or GABAergic interneurons because of their poor specificity. Lastly, we examine neurons of the postnatal hippocampal molecular layers and show cell type-specific differences in their dendritic/axonal morphologies and density distributions, as well as in their membrane properties and spontaneous synaptic inputs. These parameters can be used to distinguish biocytin-filled and/or electrophysiologically recorded neurons and should be considered to avoid interpretational mistakes.
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17
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Terminal neuron localization to the upper cortical plate is controlled by the transcription factor NEUROD2. Sci Rep 2019; 9:19697. [PMID: 31873146 PMCID: PMC6927953 DOI: 10.1038/s41598-019-56171-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Accepted: 12/06/2019] [Indexed: 12/15/2022] Open
Abstract
Excitatory neurons of the mammalian cerebral cortex are organized into six functional layers characterized by unique patterns of connectivity, as well as distinctive physiological and morphological properties. Cortical layers appear after a highly regulated migration process in which cells move from the deeper, proliferative zone toward the superficial layers. Importantly, defects in this radial migration process have been implicated in neurodevelopmental and psychiatric diseases. Here we report that during the final stages of migration, transcription factor Neurogenic Differentiation 2 (Neurod2) contributes to terminal cellular localization within the cortical plate. In mice, in utero knockdown of Neurod2 resulted in reduced numbers of neurons localized to the uppermost region of the developing cortex, also termed the primitive cortical zone. Our ChIP-Seq and RNA-Seq analyses of genes regulated by NEUROD2 in the developing cortex identified a number of key target genes with known roles in Reelin signaling, a critical regulator of neuronal migration. Our focused analysis of regulation of the Reln gene, encoding the extracellular ligand REELIN, uncovered NEUROD2 binding to conserved E-box elements in multiple introns. Furthermore, we demonstrate that knockdown of NEUROD2 in primary cortical neurons resulted in a strong increase in Reln gene expression at the mRNA level, as well as a slight upregulation at the protein level. These data reveal a new role for NEUROD2 during the late stages of neuronal migration, and our analysis of its genomic targets offers new genes with potential roles in cortical lamination.
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18
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Lee YH, Lee HT, Chen CL, Chang CH, Hsu CY, Shyu WC. Role of FOXC1 in regulating APSCs self-renewal via STI-1/PrP C signaling. Am J Cancer Res 2019; 9:6443-6465. [PMID: 31588228 PMCID: PMC6771253 DOI: 10.7150/thno.35619] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Accepted: 07/20/2019] [Indexed: 01/03/2023] Open
Abstract
Forkhead box protein C1 (FOXC1) is known to regulate developmental processes in the skull and brain. Methods: The unique multipotent arachnoid-pia stem cells (APSCs) isolated from human and mouse arachnoid-pia membranes of meninges were grown as 3D spheres and displayed a capacity for self-renewal. Additionally, APSCs also expressed the surface antigens as mesenchymal stem cells. By applying the FOXC1 knockout mice and mouse brain explants, signaling cascade of FOXC1-STI-1-PrPC was investigated to demonstrate the molecular regulatory pathway for APSCs self-renewal. Moreover, APSCs implantation in stroke model was also verified whether neurogenic property of APSCs could repair the ischemic insult of the stroke brain. Results: Activated FOXC1 regulated the proliferation of APSCs in a cell cycle-dependent manner, whereas FOXC1-mediated APSCs self-renewal was abolished in FOXC1 knockout mice (FOXC1-/- mice). Moreover, upregulation of STI-1 regulated by FOXC1 enhanced cell survival and self-renewal of APSCs through autocrine signaling of cellular prion protein (PrPC). Mouse brain explants STI-1 rescues the cortical phenotype in vitro and induces neurogenesis in the FOXC1 -/- mouse brain. Furthermore, administration of APSCs in ischemic brain restored the neuroglial microenvironment and improved neurological dysfunction. Conclusion: We identified a novel role for FOXC1 in the direct regulation of the STI-1-PrPC signaling pathway to promote cell proliferation and self-renewal of APSCs.
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19
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Han X, Gu X, Zhang Q, Wang Q, Cheng Y, Pleasure SJ, Zhao C. FoxG1 Directly Represses Dentate Granule Cell Fate During Forebrain Development. Front Cell Neurosci 2018; 12:452. [PMID: 30532694 PMCID: PMC6265346 DOI: 10.3389/fncel.2018.00452] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Accepted: 11/08/2018] [Indexed: 01/27/2023] Open
Abstract
The cortex consists of 100s of neuronal subtypes that are organized into distinct functional regions; however, the mechanisms underlying cell fate determination remain unclear. Foxg1 is involved in several developmental processes, including telencephalic patterning, cell proliferation and cell fate determination. Constitutive disruption of Foxg1 leads to the transformation of cortical neurons into Cajal-Retzius (CR) cells, accompanied by a substantial expansion of the cortical hem through the consumption of the cortex. However, rather than the induction of a cell fate switch, another group has reported a large lateral to medial repatterning of the developing telencephalon as the explanation for this change in cell type output. Here, we conditionally disrupted Foxg1 in telencephalic progenitor cells by crossing Foxg1fl/fl mice with Nestin-CreERTM mice combined with tamoxifen (TM) induction at distinct developmental stages beginning at E10.5 to further elucidate the role of FoxG1 in cell fate determination after telencephalon pattern formation. The number of dentate gyrus (DG) granule-like cells was significantly increased in the cortex. The increase was even detected after deletion at E14.5. In vivo mosaic deletion and in vitro cell culture further revealed a cell-autonomous role for FoxG1 in repressing granule cell fate. However, the cortical hem, which is required for the patterning and the development of the hippocampus, was only slightly enlarged and thus may not contribute to the cell fate switch. Lef1 expression was significantly upregulated in the lateral, cortical VZ and FoxG1 may function upstream of Wnt signaling. Our results provide new insights into the functions of FoxG1 and the mechanisms of cell fate determination during telencephalic development.
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Affiliation(s)
- Xiao Han
- Key Laboratory of Developmental Genes and Human Diseases, Ministry of Education, School of Medicine, Southeast University, Nanjing, China
| | - Xiaochun Gu
- Key Laboratory of Developmental Genes and Human Diseases, Ministry of Education, School of Medicine, Southeast University, Nanjing, China
| | - Qianqian Zhang
- Key Laboratory of Developmental Genes and Human Diseases, Ministry of Education, School of Medicine, Southeast University, Nanjing, China
| | - Qingxia Wang
- Key Laboratory of Developmental Genes and Human Diseases, Ministry of Education, School of Medicine, Southeast University, Nanjing, China
| | - Yao Cheng
- Key Laboratory of Developmental Genes and Human Diseases, Ministry of Education, School of Medicine, Southeast University, Nanjing, China
| | - Samuel J Pleasure
- Programs in Neuroscience and Developmental Stem Cell Biology, Department of Neurology, Weill Institute for Neuroscience, University of California, San Francisco, San Francisco, CA, United States
| | - Chunjie Zhao
- Key Laboratory of Developmental Genes and Human Diseases, Ministry of Education, School of Medicine, Southeast University, Nanjing, China
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20
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Sun L, Chen R, Bai Y, Li J, Wu Q, Shen Q, Wang X. Morphological and Physiological Characteristics of Ebf2-EGFP-Expressing Cajal-Retzius Cells in Developing Mouse Neocortex. Cereb Cortex 2018; 29:3864-3878. [DOI: 10.1093/cercor/bhy265] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Revised: 09/10/2018] [Indexed: 12/22/2022] Open
Abstract
Abstract
Cajal-Retzius (CR) cells are one of the earliest populations of neurons in the cerebral cortex of rodents and primates, and they play a critical role in corticogenesis and cortical lamination during neocortical development. However, a comprehensive morphological and physiological profile of CR cells in the mouse neocortex has not yet been established. Here, we systematically investigated the dynamic development of CR cells in Tg(Ebf2-EGFP)58Gsat/Mmcd mice. The morphological complexity, membrane activities and presynaptic inputs of CR cells coordinately increase and reach a plateau at P5–P9 before regressing. Using 3D reconstruction, we delineated a parallel-stratification pattern of the axonal extension of CR cells. Furthermore, we found that the morphological structure and presynaptic inputs of CR cells were disturbed in Reelin-deficient mice. These findings confirm that CR cells undergo a transient maturation process in layer 1 before disappearing. Importantly, Reelin deficiency impairs the formation of synaptic connections onto CR cells. In conclusion, our results provide insights into the rapid maturation and axonal stratification of CR cells in layer 1. These findings suggest that both the electrophysiological activities and the morphology of CR cells provide vital guidance for the modulation of early circuits, in a Reelin-dependent manner.
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Affiliation(s)
- Le Sun
- Institute of Biophysics, State Key Laboratory of Brain and Cognitive Sciences, CAS Center for Excellence in Brain Science and Intelligence Technology; Chinese Academy of Sciences, Beijing, China
| | - Ruiguo Chen
- Institute of Biophysics, State Key Laboratory of Brain and Cognitive Sciences, CAS Center for Excellence in Brain Science and Intelligence Technology; Chinese Academy of Sciences, Beijing, China
- The College of Life Science, University of Chinese Academy of Sciences, Beijing, China
| | - Ye Bai
- Institute of Biophysics, State Key Laboratory of Brain and Cognitive Sciences, CAS Center for Excellence in Brain Science and Intelligence Technology; Chinese Academy of Sciences, Beijing, China
- The College of Life Science, University of Chinese Academy of Sciences, Beijing, China
| | - Jia Li
- PTN graduate program, School of Life Science, Peking University, Beijing, China
| | - Qian Wu
- Institute of Biophysics, State Key Laboratory of Brain and Cognitive Sciences, CAS Center for Excellence in Brain Science and Intelligence Technology; Chinese Academy of Sciences, Beijing, China
| | - Qin Shen
- Tongji Hospital, Brain and Spinal Cord Innovative Research Center, School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Xiaoqun Wang
- Institute of Biophysics, State Key Laboratory of Brain and Cognitive Sciences, CAS Center for Excellence in Brain Science and Intelligence Technology; Chinese Academy of Sciences, Beijing, China
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21
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Ruiz-Reig N, Andres B, Lamonerie T, Theil T, Fairén A, Studer M. The caudo-ventral pallium is a novel pallial domain expressing Gdf10 and generating Ebf3-positive neurons of the medial amygdala. Brain Struct Funct 2018; 223:3279-3295. [PMID: 29869132 DOI: 10.1007/s00429-018-1687-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Accepted: 05/18/2018] [Indexed: 12/16/2022]
Abstract
In rodents, the medial nucleus of the amygdala receives direct inputs from the accessory olfactory bulbs and is mainly implicated in pheromone-mediated reproductive and defensive behaviors. The principal neurons of the medial amygdala are GABAergic neurons generated principally in the caudo-ventral medial ganglionic eminence and preoptic area. Beside GABAergic neurons, the medial amygdala also contains glutamatergic Otp-expressing neurons cells generated in the lateral hypothalamic neuroepithelium and a non-well characterized Pax6-positive population. In the present work, we describe a novel glutamatergic Ebf3-expressing neuronal subpopulation distributed within the periphery of the postero-ventral medial amygdala. These neurons are generated in a pallial domain characterized by high expression of Gdf10. This territory is topologically the most caudal tier of the ventral pallium and accordingly, we named it Caudo-Ventral Pallium (CVP). In the absence of Pax6, the CVP is disrupted and Ebf3-expressing neurons fail to be generated. Overall, this work proposes a novel model of the neuronal composition of the medial amygdala and unravels for the first time a new novel pallial subpopulation originating from the CVP and expressing the transcription factor Ebf3.
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Affiliation(s)
- Nuria Ruiz-Reig
- Université Côte d'Azur (UCA), CNRS, Inserm, Institut de Biologie Valrose (iBV), 06108, Nice, France.
- Instituto de Neurociencias (Consejo Superior de Investigaciones Científicas-Universidad Miguel Hernández, CSIC-UMH), 03550, San Juan de Alicante, Spain.
| | - Belen Andres
- Instituto de Neurociencias (Consejo Superior de Investigaciones Científicas-Universidad Miguel Hernández, CSIC-UMH), 03550, San Juan de Alicante, Spain
| | - Thomas Lamonerie
- Université Côte d'Azur (UCA), CNRS, Inserm, Institut de Biologie Valrose (iBV), 06108, Nice, France
| | - Thomas Theil
- Centre for Discovery Brain Sciences, Hugh Robson Building, University of Edinburgh, Edinburgh, EH8 9XD, UK
| | - Alfonso Fairén
- Instituto de Neurociencias (Consejo Superior de Investigaciones Científicas-Universidad Miguel Hernández, CSIC-UMH), 03550, San Juan de Alicante, Spain
- , Palau 11, 03550, San Juan de Alicante, Spain
| | - Michèle Studer
- Université Côte d'Azur (UCA), CNRS, Inserm, Institut de Biologie Valrose (iBV), 06108, Nice, France.
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22
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Ruiz-Reig N, Andrés B, Huilgol D, Grove EA, Tissir F, Tole S, Theil T, Herrera E, Fairén A. Lateral Thalamic Eminence: A Novel Origin for mGluR1/Lot Cells. Cereb Cortex 2018; 27:2841-2856. [PMID: 27178193 DOI: 10.1093/cercor/bhw126] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
A unique population of cells, called "lot cells," circumscribes the path of the lateral olfactory tract (LOT) in the rodent brain and acts to restrict its position at the lateral margin of the telencephalon. Lot cells were believed to originate in the dorsal pallium (DP). We show that Lhx2 null mice that lack a DP show a significant increase in the number of mGluR1/lot cells in the piriform cortex, indicating a non-DP origin of these cells. Since lot cells present common developmental features with Cajal-Retzius (CR) cells, we analyzed Wnt3a- and Dbx1-reporter mouse lines and found that mGluR1/lot cells are not generated in the cortical hem, ventral pallium, or septum, the best characterized sources of CR cells. Finally, we identified a novel origin for the lot cells by combining in utero electroporation assays and histochemical characterization. We show that mGluR1/lot cells are specifically generated in the lateral thalamic eminence and that they express mitral cell markers, although a minority of them express ΔNp73 instead. We conclude that most mGluR1/lot cells are prospective mitral cells migrating to the accessory olfactory bulb (OB), whereas mGluR1+, ΔNp73+ cells are CR cells that migrate through the LOT to the piriform cortex and the OB.
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Affiliation(s)
- Nuria Ruiz-Reig
- Instituto de Neurociencias (Consejo Superior de Investigaciones Científicas - Universidad Miguel Hernández, CSIC - UMH), San Juan de Alicante, Spain
| | - Belén Andrés
- Instituto de Neurociencias (Consejo Superior de Investigaciones Científicas - Universidad Miguel Hernández, CSIC - UMH), San Juan de Alicante, Spain
| | - Dhananjay Huilgol
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, India.,Current address: Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
| | | | - Fadel Tissir
- Université catholique de Louvain, Institute of Neuroscience, Brussels, Belgium
| | - Shubha Tole
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, India
| | - Thomas Theil
- Centre for Integrative Physiology, University of Edinburgh, Edinburgh, UK
| | - Eloisa Herrera
- Instituto de Neurociencias (Consejo Superior de Investigaciones Científicas - Universidad Miguel Hernández, CSIC - UMH), San Juan de Alicante, Spain
| | - Alfonso Fairén
- Instituto de Neurociencias (Consejo Superior de Investigaciones Científicas - Universidad Miguel Hernández, CSIC - UMH), San Juan de Alicante, Spain
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23
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A Prdm8 target gene Ebf3 regulates multipolar-to-bipolar transition in migrating neocortical cells. Biochem Biophys Res Commun 2017; 495:388-394. [PMID: 29113800 DOI: 10.1016/j.bbrc.2017.11.021] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Accepted: 11/03/2017] [Indexed: 01/08/2023]
Abstract
Precise control of neuronal migration is essential for the development of the neocortex. However, the molecular mechanisms underlying neuronal migration remain largely unknown. Here we identified helix-loop-helix transcription factor Ebf3 as a Prdm8 target gene, and found that Ebf3 is a key regulator of neuronal migration via multipolar-to-bipolar transition. Ebf3 knockdown cells exhibited severe defects in the formation of leading processes and an inhibited shift to the locomotion mode. Moreover, we found that Ebf3 knockdown represses NeuroD1 transcription, and NeuroD1 overexpression partially rescued migration defects in Ebf3 knockdown cells. Our findings highlight the critical role of Ebf3 in multipolar-to-bipolar transition via positive feedback regulation of NeuroD1 in the developing neocortex.
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24
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Frade-Pérez MD, Miquelajáuregui A, Varela-Echavarría A. Origin and Migration of Olfactory Cajal-Retzius Cells. Front Neuroanat 2017; 11:97. [PMID: 29163070 PMCID: PMC5671926 DOI: 10.3389/fnana.2017.00097] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2017] [Accepted: 10/17/2017] [Indexed: 11/29/2022] Open
Abstract
Early telencephalic development involves the migration of diverse cell types that can be identified by specific molecular markers. Most prominent among them are Cajal-Retzius (CR) cells that emanate mainly from the cortical hem and to a lesser extent from rostrolateral, septal and caudo-medial regions. One additional territory proposed to give rise to CR cells that migrate dorsally into the neocortex lies at the ventral pallium, although contradictory results question this notion. With the use of a cell-permeable fluorescent tracer in cultured embryos, we identified novel migratory paths of putative CR cells and other populations that originate from the rostrolateral telencephalon at its olfactory region. Moreover, extensive labeling on the lateral telencephalon along its rostro-caudal extent failed to reveal a dorsally-migrating CR cell population from the ventral pallium at the stages analyzed. Hence, this work reveals a novel olfactory CR cell migration and supports the idea that the ventral pallium, where diverse types of neurons converge, does not actually generate CR cells.
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Affiliation(s)
| | - Amaya Miquelajáuregui
- Instituto de Neurobiología, Universidad Nacional Autónoma de México, Querétaro, Mexico
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25
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Desfilis E, Abellán A, Sentandreu V, Medina L. Expression of regulatory genes in the embryonic brain of a lizard and implications for understanding pallial organization and evolution. J Comp Neurol 2017; 526:166-202. [PMID: 28891227 PMCID: PMC5765483 DOI: 10.1002/cne.24329] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2017] [Revised: 08/13/2017] [Accepted: 09/01/2017] [Indexed: 02/03/2023]
Abstract
The comparison of gene expression patterns in the embryonic brain of mouse and chicken is being essential for understanding pallial organization. However, the scarcity of gene expression data in reptiles, crucial for understanding evolution, makes it difficult to identify homologues of pallial divisions in different amniotes. We cloned and analyzed the expression of the genes Emx1, Lhx2, Lhx9, and Tbr1 in the embryonic telencephalon of the lacertid lizard Psammodromus algirus. The comparative expression patterns of these genes, critical for pallial development, are better understood when using a recently proposed six‐part model of pallial divisions. The lizard medial pallium, expressing all genes, includes the medial and dorsomedial cortices, and the majority of the dorsal cortex, except the region of the lateral cortical superposition. The latter is rich in Lhx9 expression, being excluded as a candidate of dorsal or lateral pallia, and may belong to a distinct dorsolateral pallium, which extends from rostral to caudal levels. Thus, the neocortex homolog cannot be found in the classical reptilian dorsal cortex, but perhaps in a small Emx1‐expressing/Lhx9‐negative area at the front of the telencephalon, resembling the avian hyperpallium. The ventral pallium, expressing Lhx9, but not Emx1, gives rise to the dorsal ventricular ridge and appears comparable to the avian nidopallium. We also identified a distinct ventrocaudal pallial sector comparable to the avian arcopallium and to part of the mammalian pallial amygdala. These data open new venues for understanding the organization and evolution of the pallium.
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Affiliation(s)
- Ester Desfilis
- Laboratory of Evolutionary and Developmental Neurobiology, Department of Experimental Medicine, Faculty of Medicine, University of Lleida, Lleida Institute for Biomedical Research Dr. Pifarré Foundation (IRBLleida), 25198, Lleida, Spain
| | - Antonio Abellán
- Laboratory of Evolutionary and Developmental Neurobiology, Department of Experimental Medicine, Faculty of Medicine, University of Lleida, Lleida Institute for Biomedical Research Dr. Pifarré Foundation (IRBLleida), 25198, Lleida, Spain
| | - Vicente Sentandreu
- Servicio Central de Apoyo a la Investigación Experimental (SCSIE), Sección de Genómica, University of València, 46100, València, Spain
| | - Loreta Medina
- Laboratory of Evolutionary and Developmental Neurobiology, Department of Experimental Medicine, Faculty of Medicine, University of Lleida, Lleida Institute for Biomedical Research Dr. Pifarré Foundation (IRBLleida), 25198, Lleida, Spain
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26
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Bernal J. Thyroid hormone regulated genes in cerebral cortex development. J Endocrinol 2017; 232:R83-R97. [PMID: 27852726 DOI: 10.1530/joe-16-0424] [Citation(s) in RCA: 91] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Accepted: 11/16/2016] [Indexed: 12/19/2022]
Abstract
The physiological and developmental effects of thyroid hormones are mainly due to the control of gene expression after interaction of T3 with the nuclear receptors. To understand the role of thyroid hormones on cerebral cortex development, knowledge of the genes regulated by T3 during specific stages of development is required. In our laboratory, we previously identified genes regulated by T3 in primary cerebrocortical cells in culture. By comparing these data with transcriptomics of purified cell types from the developing cortex, the cellular targets of T3 can be identified. In addition, many of the genes regulated transcriptionally by T3 have defined roles in cortex development, from which the role of T3 can be derived. This review analyzes the specific roles of T3-regulated genes in the different stages of cortex development within the physiological frame of the developmental changes of thyroid hormones and receptor concentrations in the human cerebral cortex during fetal development. These data indicate an increase in the sensitivity to T3 during the second trimester of fetal development. The main cellular targets of T3 appear to be the Cajal-Retzius and the subplate neurons. On the other hand, T3 regulates transcriptionally genes encoding extracellular matrix proteins, involved in cell migration and the control of diverse signaling pathways.
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Affiliation(s)
- Juan Bernal
- Instituto de Investigaciones BiomédicasConsejo Superior de Investigaciones Científicas y Universidad Autónoma de Madrid, and Center for Biomedical Research on Rare Diseases, Instituto de Salud Carlos III, Madrid, Spain
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27
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Sleven H, Welsh SJ, Yu J, Churchill ME, Wright CF, Henderson A, Horvath R, Rankin J, Vogt J, Magee A, McConnell V, Green A, King MD, Cox H, Armstrong L, Lehman A, Nelson TN, Williams J, Clouston P, Hagman J, Németh AH, Hagman J, Németh AH. De Novo Mutations in EBF3 Cause a Neurodevelopmental Syndrome. Am J Hum Genet 2017; 100:138-150. [PMID: 28017370 DOI: 10.1016/j.ajhg.2016.11.020] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Accepted: 11/22/2016] [Indexed: 11/29/2022] Open
Abstract
Early B cell factor 3 (EBF3) is an atypical transcription factor that is thought to influence the laminar formation of the cerebral cortex. Here, we report that de novo mutations in EBF3 cause a complex neurodevelopmental syndrome. The mutations were identified in two large-scale sequencing projects: the UK Deciphering Developmental Disorders (DDD) study and the Canadian Clinical Assessment of the Utility of Sequencing and Evaluation as a Service (CAUSES) study. The core phenotype includes moderate to severe intellectual disability, and many individuals exhibit cerebellar ataxia, subtle facial dysmorphism, strabismus, and vesicoureteric reflux, suggesting that EBF3 has a widespread developmental role. Pathogenic de novo variants identified in EBF3 include multiple loss-of-function and missense mutations. Structural modeling suggested that the missense mutations affect DNA binding. Functional analysis of mutant proteins with missense substitutions revealed reduced transcriptional activities and abilities to form heterodimers with wild-type EBF3. We conclude that EBF3, a transcription factor previously unknown to be associated with human disease, is important for brain and other organ development and warrants further investigation.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - James Hagman
- Program in Molecular Biology, University of Colorado, Anschutz Medical Campus, Aurora, CO 80045, USA; Department of Biomedical Research, National Jewish Health, Denver, CO 80206, USA.
| | - Andrea H Németh
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford OX3 9DU, UK; Oxford Centre for Genomic Medicine, Nuffield Orthopaedic Centre, Oxford University Hospitals NHS Foundation Trust, Windmill Road, Headington, Oxford OX3 7HE, UK.
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28
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Chao HT, Davids M, Burke E, Pappas JG, Rosenfeld JA, McCarty AJ, Davis T, Wolfe L, Toro C, Tifft C, Xia F, Stong N, Johnson TK, Warr CG, Yamamoto S, Adams DR, Markello TC, Gahl WA, Bellen HJ, Wangler MF, Malicdan MCV, Adams DR, Adams CJ, Alejandro ME, Allard P, Ashley EA, Bacino CA, Balasubramanyam A, Barseghyan H, Beggs AH, Bellen HJ, Bernstein JA, Bick DP, Birch CL, Boone BE, Briere LC, Brown DM, Brush M, Burrage LC, Chao KR, Clark GD, Cogan JD, Cooper CM, Craigen WJ, Davids M, Dayal JG, Dell'Angelica EC, Dhar SU, Dipple KM, Donnell-Fink LA, Dorrani N, Dorset DC, Draper DD, Dries AM, Eckstein DJ, Emrick LT, Eng CM, Esteves C, Estwick T, Fisher PG, Frisby TS, Frost K, Gahl WA, Gartner V, Godfrey RA, Goheen M, Golas GA, Goldstein DB, Gordon M“GG, Gould SE, Gourdine JPF, Graham BH, Groden CA, Gropman AL, Hackbarth ME, Haendel M, Hamid R, Hanchard NA, Handley LH, Hardee I, Herzog MR, Holm IA, Howerton EM, Jacob HJ, Jain M, Jiang YH, Johnston JM, Jones AL, Koehler AE, Koeller DM, Kohane IS, Kohler JN, Krasnewich DM, Krieg EL, Krier JB, Kyle JE, Lalani SR, Latham L, Latour YL, Lau CC, Lazar J, Lee BH, Lee H, Lee PR, Levy SE, Levy DJ, Lewis RA, Liebendorder AP, Lincoln SA, Loomis CR, Loscalzo J, Maas RL, Macnamara EF, MacRae CA, Maduro VV, Malicdan MCV, Mamounas LA, Manolio TA, Markello TC, Mashid AS, Mazur P, McCarty AJ, McConkie-Rosell A, McCray AT, Metz TO, Might M, Moretti PM, Mulvihill JJ, Murphy JL, Muzny DM, Nehrebecky ME, Nelson SF, Newberry JS, Newman JH, Nicholas SK, Novacic D, Orange JS, Pallais JC, Palmer CG, Papp JC, Pena LD, Phillips JA, Posey JE, Postlethwait JH, Potocki L, Pusey BN, Ramoni RB, Rodan LH, Sadozai S, Schaffer KE, Schoch K, Schroeder MC, Scott DA, Sharma P, Shashi V, Silverman EK, Sinsheimer JS, Soldatos AG, Spillmann RC, Splinter K, Stoler JM, Stong N, Strong KA, Sullivan JA, Sweetser DA, Thomas SP, Tift CJ, Tolman NJ, Toro C, Tran AA, Valivullah ZM, Vilain E, Waggott DM, Wahl CE, Walley NM, Walsh CA, Wangler MF, Warburton M, Ward PA, Waters KM, Webb-Robertson BJM, Weech AA, Westerfield M, Wheeler MT, Wise AL, Worthe LA, Worthey EA, Yamamoto S, Yang Y, Yu G, Zornio PA. A Syndromic Neurodevelopmental Disorder Caused by De Novo Variants in EBF3. Am J Hum Genet 2017; 100:128-137. [PMID: 28017372 PMCID: PMC5223093 DOI: 10.1016/j.ajhg.2016.11.018] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Accepted: 11/21/2016] [Indexed: 02/06/2023] Open
Abstract
Early B cell factor 3 (EBF3) is a member of the highly evolutionarily conserved Collier/Olf/EBF (COE) family of transcription factors. Prior studies on invertebrate and vertebrate animals have shown that EBF3 homologs are essential for survival and that loss-of-function mutations are associated with a range of nervous system developmental defects, including perturbation of neuronal development and migration. Interestingly, aristaless-related homeobox (ARX), a homeobox-containing transcription factor critical for the regulation of nervous system development, transcriptionally represses EBF3 expression. However, human neurodevelopmental disorders related to EBF3 have not been reported. Here, we describe three individuals who are affected by global developmental delay, intellectual disability, and expressive speech disorder and carry de novo variants in EBF3. Associated features seen in these individuals include congenital hypotonia, structural CNS malformations, ataxia, and genitourinary abnormalities. The de novo variants affect a single conserved residue in a zinc finger motif crucial for DNA binding and are deleterious in a fly model. Our findings indicate that mutations in EBF3 cause a genetic neurodevelopmental syndrome and suggest that loss of EBF3 function might mediate a subset of neurologic phenotypes shared by ARX-related disorders, including intellectual disability, abnormal genitalia, and structural CNS malformations.
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29
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de Frutos C, Bouvier G, Arai Y, Thion M, Lokmane L, Keita M, Garcia-Dominguez M, Charnay P, Hirata T, Riethmacher D, Grove E, Tissir F, Casado M, Pierani A, Garel S. Reallocation of Olfactory Cajal-Retzius Cells Shapes Neocortex Architecture. Neuron 2016; 92:435-448. [DOI: 10.1016/j.neuron.2016.09.020] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2015] [Revised: 07/13/2016] [Accepted: 09/06/2016] [Indexed: 11/25/2022]
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30
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Barber M, Pierani A. Tangential migration of glutamatergic neurons and cortical patterning during development: Lessons from Cajal-Retzius cells. Dev Neurobiol 2015; 76:847-81. [PMID: 26581033 DOI: 10.1002/dneu.22363] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Revised: 11/12/2015] [Accepted: 11/13/2015] [Indexed: 12/14/2022]
Abstract
Tangential migration is a mode of cell movement, which in the developing cerebral cortex, is defined by displacement parallel to the ventricular surface and orthogonal to the radial glial fibers. This mode of long-range migration is a strategy by which distinct neuronal classes generated from spatially and molecularly distinct origins can integrate to form appropriate neural circuits within the cortical plate. While it was previously believed that only GABAergic cortical interneurons migrate tangentially from their origins in the subpallial ganglionic eminences to integrate in the cortical plate, it is now known that transient populations of glutamatergic neurons also adopt this mode of migration. These include Cajal-Retzius cells (CRs), subplate neurons (SPs), and cortical plate transient neurons (CPTs), which have crucial roles in orchestrating the radial and tangential development of the embryonic cerebral cortex in a noncell-autonomous manner. While CRs have been extensively studied, it is only in the last decade that the molecular mechanisms governing their tangential migration have begun to be elucidated. To date, the mechanisms of SPs and CPTs tangential migration remain unknown. We therefore review the known signaling pathways, which regulate parameters of CRs migration including their motility, contact-redistribution and adhesion to the pial surface, and discuss this in the context of how CR migration may regulate their signaling activity in a spatial and temporal manner. © 2015 Wiley Periodicals, Inc. Develop Neurobiol 76: 847-881, 2016.
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Affiliation(s)
- Melissa Barber
- Institut Jacques-Monod, CNRS, Université Paris Diderot, Sorbonne Cité, Paris, France.,Department of Cell and Developmental Biology, University College London, WC1E 6BT, United Kingdom
| | - Alessandra Pierani
- Institut Jacques-Monod, CNRS, Université Paris Diderot, Sorbonne Cité, Paris, France
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31
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Optogenetic activation of cajal-retzius cells reveals their glutamatergic output and a novel feedforward circuit in the developing mouse hippocampus. J Neurosci 2014; 34:13018-32. [PMID: 25253849 DOI: 10.1523/jneurosci.1407-14.2014] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Cajal-Retzius cells orchestrate the development of cortical circuits by secreting the glycoprotein reelin. However, their computational functions are still unknown. In fact, the nature of their postsynaptic targets, major neurotransmitter released, as well as the class of postsynaptic receptors activated by their firing remain unclear. Here, we have addressed these questions by activating Cajal-Retzius cells optogenetically in mouse hippocampal slices. Light delivered to stratum lacunosum-moleculare triggered EPSCs both on local interneurons and on pyramidal cells. Responses recorded under voltage-clamp conditions had identical short latencies and similar amplitudes, but were kinetically different (i.e., faster in interneurons vs pyramidal cells). In both cases, responses were blocked by TTX, indicating that they were generated by action potential-dependent release. Responses in interneurons were rescued by the addition of 4-AP to TTX, and decreased when presynaptic firing in Cajal-Retzius cells was reduced by the chemokine CXCL12, indicating the existence of a direct Cajal-Retzius cell-interneuron monosynaptic connection. Although the combined application of 4-AP and TTX did not rescue responses in pyramidal cells, neither were they affected by the GABAA receptor blocker gabazine, which would be expected if they were polysynaptic. Both connections showed physiological and pharmacological properties indicating the involvement of AMPA- and NMDA-type glutamate receptors. The connectivity from presynaptic Cajal-Retzius cells to interneurons was strong enough to generate long-latency feedforward GABAergic input onto pyramidal cells. We propose that this newly defined Cajal-Retzius cell-dependent microcircuit may regulate synaptic plasticity and dendritic development in stratum lacunosum-moleculare, thus impacting the integrative properties of the developing hippocampus.
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32
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Kirischuk S, Luhmann HJ, Kilb W. Cajal-Retzius cells: update on structural and functional properties of these mystic neurons that bridged the 20th century. Neuroscience 2014; 275:33-46. [PMID: 24931764 DOI: 10.1016/j.neuroscience.2014.06.009] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2014] [Revised: 06/03/2014] [Accepted: 06/03/2014] [Indexed: 02/02/2023]
Abstract
Cajal-Retzius cells (CRc) represent a mostly transient neuronal cell type localized in the uppermost layer of the developing neocortex. The observation that CRc are a major source of the extracellular matrix protein reelin, which is essential for the laminar development of the cerebral cortex, attracted the interest in this unique cell type. In this review we will (i) describe the morphological and molecular properties of neocortical CRc, with a special emphasize on the question which markers can be used to identify CRc, (ii) summarize reports that identified the different developmental origins of CRc, (iii) discuss the fate of CRc, including recent evidence for apoptotic cell death and a possible persistence of some CRc, (iv) provide a detailed description of the electrical membrane properties and transmitter receptors of CRc, and (v) address the role of CRc in early neuronal circuits and cortical development. Finally, we speculate whether CRc may provide a link between early network activity and the structural maturation of neocortical circuits.
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Affiliation(s)
- S Kirischuk
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University, Duesbergweg 6, D-55128 Mainz, Germany
| | - H J Luhmann
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University, Duesbergweg 6, D-55128 Mainz, Germany
| | - W Kilb
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University, Duesbergweg 6, D-55128 Mainz, Germany.
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33
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Gil-Sanz C, Franco SJ, Martinez-Garay I, Espinosa A, Harkins-Perry S, Müller U. Cajal-Retzius cells instruct neuronal migration by coincidence signaling between secreted and contact-dependent guidance cues. Neuron 2013; 79:461-77. [PMID: 23931996 DOI: 10.1016/j.neuron.2013.06.040] [Citation(s) in RCA: 105] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/17/2013] [Indexed: 11/25/2022]
Abstract
Cajal-Retzius (CR) cells are a transient cell population of the CNS that is critical for brain development. In the neocortex, CR cells secrete reelin to instruct the radial migration of projection neurons. It has remained unexplored, however, whether CR cells provide additional molecular cues important for brain development. Here, we show that CR cells express the immunoglobulin-like adhesion molecule nectin1, whereas neocortical projection neurons express its preferred binding partner, nectin3. We demonstrate that nectin1- and nectin3-mediated interactions between CR cells and migrating neurons are critical for radial migration. Furthermore, reelin signaling to Rap1 promotes neuronal Cdh2 function via nectin3 and afadin, thus directing the broadly expressed homophilic cell adhesion molecule Cdh2 toward mediating heterotypic cell-cell interactions between neurons and CR cells. Our findings identify nectins and afadin as components of the reelin signaling pathway and demonstrate that coincidence signaling between CR cell-derived secreted and short-range guidance cues direct neuronal migration.
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Affiliation(s)
- Cristina Gil-Sanz
- Department of Molecular and Cellular Neuroscience, Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, CA 92037, USA
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34
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Kumamoto T, Toma KI, Gunadi, McKenna WL, Kasukawa T, Katzman S, Chen B, Hanashima C. Foxg1 coordinates the switch from nonradially to radially migrating glutamatergic subtypes in the neocortex through spatiotemporal repression. Cell Rep 2013; 3:931-45. [PMID: 23523356 DOI: 10.1016/j.celrep.2013.02.023] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2012] [Revised: 10/08/2012] [Accepted: 02/19/2013] [Indexed: 12/19/2022] Open
Abstract
The specification of neuronal subtypes in the cerebral cortex proceeds in a temporal manner; however, the regulation of the transitions between the sequentially generated subtypes is poorly understood. Here, we report that the forkhead box transcription factor Foxg1 coordinates the production of neocortical projection neurons through the global repression of a default gene program. The delayed activation of Foxg1 was necessary and sufficient to induce deep-layer neurogenesis, followed by a sequential wave of upper-layer neurogenesis. A genome-wide analysis revealed that Foxg1 binds to mammalian-specific noncoding sequences to repress over 12 transcription factors expressed in early progenitors, including Ebf2/3, Dmrt3, Dmrta1, and Eya2. These findings reveal an unexpected prolonged competence of progenitors to initiate corticogenesis at a progressed stage during development and identify Foxg1 as a critical initiator of neocorticogenesis through spatiotemporal repression, a system that balances the production of nonradially and radially migrating glutamatergic subtypes during mammalian cortical expansion.
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Affiliation(s)
- Takuma Kumamoto
- Laboratory for Neocortical Development, RIKEN Center for Developmental Biology, Kobe 650-0047, Japan
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35
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Roy A, Gonzalez-Gomez M, Pierani A, Meyer G, Tole S. Lhx2 regulates the development of the forebrain hem system. ACTA ACUST UNITED AC 2013; 24:1361-72. [PMID: 23307637 PMCID: PMC3977624 DOI: 10.1093/cercor/bhs421] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Early brain development is regulated by the coordinated actions of multiple signaling centers at key boundaries between compartments. Three telencephalic midline structures are in a position to play such roles in forebrain patterning: The cortical hem, the septum, and the thalamic eminence at the diencephalic–telencephalic boundary. These structures express unique complements of signaling molecules, and they also produce distinct populations of Cajal–Retzius cells, which are thought to act as “mobile patterning units,” migrating tangentially to cover the telencephalic surface. We show that these 3 structures require the transcription factor Lhx2 to delimit their extent. In the absence of Lhx2 function, all 3 structures are greatly expanded, and the Cajal–Retzius cell population is dramatically increased. We propose that the hem, septum, and thalamic eminence together form a “forebrain hem system” that defines and regulates the formation of the telencephalic midline. Disruptions in the forebrain hem system may be implicated in severe brain malformations such as holoprosencephaly. Lhx2 functions as a central regulator of this system's development. Since all components of the forebrain hem system have been identified across several vertebrate species, the mechanisms that regulate them may have played a fundamental role in driving key aspects of forebrain evolution.
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Affiliation(s)
- Achira Roy
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, India
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Robust formation and maintenance of continuous stratified cortical neuroepithelium by laminin-containing matrix in mouse ES cell culture. PLoS One 2012; 7:e53024. [PMID: 23300850 PMCID: PMC3534089 DOI: 10.1371/journal.pone.0053024] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2012] [Accepted: 11/22/2012] [Indexed: 01/11/2023] Open
Abstract
In the mammalian cortex, the dorsal telencephalon exhibits a characteristic stratified structure. We previously reported that three-dimensional (3D) culture of mouse ES cells (mESCs) can efficiently generate cortical neuroepithelium (NE) and layer-specific cortical neurons. However, the cortical NE generated in this mESC culture was structurally unstable and broke into small neural rosettes by culture day 7, suggesting that some factors for reinforcing the structural integrity were missing. Here we report substantial supporting effects of the extracellular matrix (ECM) protein laminin on the continuous formation of properly polarized cortical NE in floating aggregate culture of mESCs. The addition of purified laminin and entactin (a laminin-associated protein), even at low concentrations, stabilized the formation of continuous cortical NE as well as the maintenance of basement membrane and prevented rosette formation. Treatment with the neutralizing ß1-integrin antibody impaired the continuous NE formation. The stabilized cortical NE exhibited typical interkinetic nuclear migration of cortical progenitors, as seen in the embryonic cortex. The laminin-treated cortical NE maintained a continuous structure even on culture days 12 and 15, and contained ventricular, basal-progenitor, cortical-plate and Cajal-Retzius cell layers. The cortical NE in this culture was flanked by cortical hem-like tissue. Furthermore, when Shh was added, ventral telencephalic structures such as lateral ganglionic eminence–like tissue formed in the region adjacent to the cortical NE. Thus, our results indicate that laminin-entactin ECM promotes the formation of structurally stable telencephalic tissues in 3D ESC culture, and supports the morphogenetic recapitulation of cortical development.
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Li XY, Chen T, Descalzi G, Koga K, Qiu S, Zhuo M. Characterization of neuronal intrinsic properties and synaptic transmission in layer I of anterior cingulate cortex from adult mice. Mol Pain 2012; 8:53. [PMID: 22818293 PMCID: PMC3495677 DOI: 10.1186/1744-8069-8-53] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2012] [Accepted: 06/26/2012] [Indexed: 01/29/2023] Open
Abstract
The neurons in neocortex layer I (LI) provide inhibition to the cortical networks. Despite increasing use of mice for the study of brain functions, few studies were reported about mouse LI neurons. In the present study, we characterized intrinsic properties of LI neurons of the anterior cingulate cortex (ACC), a key cortical area for sensory and cognitive functions, by using whole-cell patch clamp recording approach. Seventy one neurons in LI and 12 pyramidal neurons in LII/III were recorded. Although all of the LI neurons expressed continuous adapting firing characteristics, the unsupervised clustering results revealed five groups in the ACC, including: Spontaneous firing neurons; Delay-sAHP neurons, Delay-fAHP neurons, and two groups of neurons with ADP, named ADP1 and ADP2, respectively. Using pharmacological approaches, we found that LI neurons received both excitatory (mediated by AMPA, kainate and NMDA receptors), and inhibitory inputs (which were mediated by GABAA receptors). Our studies provide the first report characterizing the electrophysiological properties of neurons in LI of the ACC from adult mice.
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Affiliation(s)
- Xiang-Yao Li
- Center for Neuron and Disease, Frontier Institute of Science and Technology, Xi'an Jiaotong University, Xi'an 710054, China
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Chiara F, Badaloni A, Croci L, Yeh ML, Cariboni A, Hoerder-Suabedissen A, Consalez GG, Eickholt B, Shimogori T, Parnavelas JG, Rakić S. Early B-cell factors 2 and 3 (EBF2/3) regulate early migration of Cajal-Retzius cells from the cortical hem. Dev Biol 2012; 365:277-89. [PMID: 22421355 PMCID: PMC3368273 DOI: 10.1016/j.ydbio.2012.02.034] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2011] [Revised: 02/24/2012] [Accepted: 02/27/2012] [Indexed: 11/26/2022]
Abstract
Cajal–Retzius (CR) cells play a crucial role in the formation of the cerebral cortex, yet the molecules that control their development are largely unknown. Here, we show that Ebf transcription factors are expressed in forebrain signalling centres—the septum, cortical hem and the pallial–subpallial boundary—known to generate CR cells. We identified Ebf2, through fate mapping studies, as a novel marker for cortical hem- and septum-derived CR cells. Loss of Ebf2 in vivo causes a transient decrease in CR cell numbers on the cortical surface due to a migratory defect in the cortical hem, and is accompanied by upregulation of Ebf3 in this and other forebrain territories that produce CR cells, without affecting proper cortical lamination. Accordingly, using in vitro preparations, we demonstrated that both Ebf2 and Ebf3, singly or together, control the migration of CR cells arising in the cortical hem. These findings provide evidence that Ebfs directly regulate CR cell development.
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Affiliation(s)
- Francesca Chiara
- Department of Cell and Developmental Biology, University College London, UK
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Gu X, Liu B, Wu X, Yan Y, Zhang Y, Wei Y, Pleasure SJ, Zhao C. Inducible genetic lineage tracing of cortical hem derived Cajal-Retzius cells reveals novel properties. PLoS One 2011; 6:e28653. [PMID: 22174859 PMCID: PMC3236758 DOI: 10.1371/journal.pone.0028653] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2011] [Accepted: 11/12/2011] [Indexed: 12/14/2022] Open
Abstract
During cortical development, Cajal-Retzius (CR) cells are among the earliest-born subclasses of neurons. These enigmatic neurons play an important role in cortical development through their expression of the extracellular protein, reelin. CR cells arise from discrete sources within the telencephalon, including the pallial-subpallial border and the medial (cortical hem) regions of the pallium. Combined evidence suggests that CR cells derived from distinct origins may have different distributions and functions. By tracing CR cells derived from the cortical hem using the inducible Cre transgenic mouse tool, Frizzled 10-CreER™, we examined the specific properties of hem-derived CR cells during cortical development. Our results show that the progenitor zone for later production of CR cells from the hem can be specifically marked as early as embryonic day 6.5 (E6.5), a pre-neural period. Moreover, using our Cre line, we found that some hem-derived CR cells migrated out along the fimbrial radial glial scaffold, which was also derived from the cortical hem, and preferentially settled in the hippocampal marginal zone, which indicated specific roles for hem-derived CR cells in hippocampal development.
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Affiliation(s)
- Xiaochun Gu
- Key Laboratory of Developmental Genes and Human Diseases, MOE, Institute of Life Science, Southeast University, Nanjing, Jiangsu, People's Republic of China
| | - Bin Liu
- Key Laboratory of Developmental Genes and Human Diseases, MOE, Institute of Life Science, Southeast University, Nanjing, Jiangsu, People's Republic of China
| | - Xiaojing Wu
- Key Laboratory of Developmental Genes and Human Diseases, MOE, Institute of Life Science, Southeast University, Nanjing, Jiangsu, People's Republic of China
| | - Yan Yan
- Key Laboratory of Developmental Genes and Human Diseases, MOE, Institute of Life Science, Southeast University, Nanjing, Jiangsu, People's Republic of China
| | - Ying Zhang
- Key Laboratory of Developmental Genes and Human Diseases, MOE, Institute of Life Science, Southeast University, Nanjing, Jiangsu, People's Republic of China
| | - Yiquan Wei
- Key Laboratory of Developmental Genes and Human Diseases, MOE, Institute of Life Science, Southeast University, Nanjing, Jiangsu, People's Republic of China
| | - Samuel J. Pleasure
- Department of Neurology, Programs in Neuroscience, Developmental Biology and Biomedical Sciences, San Francisco, California, United States of America
| | - Chunjie Zhao
- Key Laboratory of Developmental Genes and Human Diseases, MOE, Institute of Life Science, Southeast University, Nanjing, Jiangsu, People's Republic of China
- * E-mail:
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The Etv1/Er81 transcription factor orchestrates activity-dependent gene regulation in the terminal maturation program of cerebellar granule cells. Proc Natl Acad Sci U S A 2011; 108:12497-502. [PMID: 21746923 DOI: 10.1073/pnas.1109940108] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In the postnatal period, cerebellar granule cells express a set of the maturation gene battery in an activity-dependent manner and establish synaptic function in the cerebellar circuitry. Using primary cultures combined with specific inhibition of signaling cascades, the present investigation revealed that the expression of the maturation genes, including the NMDA glutamate receptor NR2C and GABA(A) receptor GABA(A)Rα6 genes, is controlled by strikingly unified signaling mechanisms that operate sequentially through stimulation of AMPA and NMDA receptors, Na(+) channels [voltage-gated Na channel type II (Nav1.2)], and voltage-dependent Ca(2+) channels. This signaling then induces the Ets variant gene 1 (Etv1/Er81) transcription factor of the ETS family in an activity-dependent manner. Consistent with the culture study, the ChIP assay indicated that Etv1 up-regulates the maturation genes in a developmentally regulated manner. This activation, as revealed by the luciferase assay, occurrs by interacting with the Etv1-interacting motifs present in the promoter region. Importantly, in vivo knockdown of Etv1 by DNA electroporation in the developing cerebellum prevents the up-regulation of the maturation genes but has no effects on preceding developmental processes occurring in the granule cells. Etv1 thus orchestrates the activity-dependent gene regulation in the terminal maturation program and specifies the identity of cerebellar granule cells.
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Puelles L. Pallio-pallial tangential migrations and growth signaling: new scenario for cortical evolution? BRAIN, BEHAVIOR AND EVOLUTION 2011; 78:108-27. [PMID: 21701143 DOI: 10.1159/000327905] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Observations accruing in recent years imply that the areal patterning and size dimensioning of the mammalian neocortex are influenced by diverse sets of tangentially migrating glutamatergic neurons that invade the cortical plate and, in so doing, modify the properties of the neopallial proliferative compartments. This developmental scenario sheds new light upon the old issue of how the mammalian neocortex evolved its more complex structure from nonmammalian antecedent forms. In reviewing these novelties, I first point out the topological position of the neopallial island as a central component of the pallium in all gnathostomes, surrounded by a ring of prospective allocortical pallial regions and a more distant set of peripheral neighboring forebrain areas. Early patterning arises from the periphery via passive planar signaling. This process probably establishes the pallium field and its basic island plus allocortical ring organization, as well as a rough prepatterning of some regional subareas. Afterwards, patterning and modulated growth are also actively influenced by the convergence of separate streams of tangentially migrating subpial cells (partly peripheral and partly allocortical in origin) which collectively form the Cajal-Retzius neuronal population in layer I. Effects of these cells include the inside-out stratification of the cortical plate and they may also contribute to the evolutionary emergence of the 6-layered neocortical structure. The most recent addition to our knowledge of pallio-pallial migrations is the existence of a subsequent deep tangential migration of ventropallial cells into the neopallial primordium, whose signaling influence upon local progenitors magnifies the cortex population by 20%. These glutamatergic cells dispersedly invade the entire cortex but largely die postnatally. The crucial implications of these data for comparative thinking on mammalian neocortex evolution and interpretation of potential homologs in sauropsids are explored. Finally, a new conjecture regarding a possible role of the hitherto disregarded lateral pallium is advanced.
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Affiliation(s)
- Luis Puelles
- Department of Human Anatomy and Psychobiology, School of Medicine, University of Murcia, Murcia, Spain.
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Chuang SM, Wang Y, Wang Q, Liu KM, Shen Q. Ebf2 Marks Early Cortical Neurogenesis and Regulates the Generation of Cajal-Retzius Neurons in the Developing Cerebral Cortex. Dev Neurosci 2011; 33:479-93. [DOI: 10.1159/000330582] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2011] [Accepted: 07/05/2011] [Indexed: 11/19/2022] Open
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Abstract
Cajal-Retzius (C-R) cells play important roles in the lamination of the mammalian cortex via reelin secretion. The genetic mechanisms underlying the development of these neurons have just begun to be unraveled. Here, we show that two closely related LIM-homeobox genes Lhx1 and Lhx5 are expressed in reelin+ cells in various regions in the mouse telencephalon at or adjacent to sites where the C-R cells are generated, including the cortical hem, the mantle region of the septal/retrobulbar area, and the ventral pallium. Whereas Lhx5 is expressed in all of these reelin-expressing domains, Lhx1 is preferentially expressed in the septal area and in a continuous domain spanning from lateral olfactory region to caudomedial territories. Genetic ablation of Lhx5 results in decreased reelin+ and p73+ cells in the neocortical anlage, in the cortical hem, and in the septal, olfactory, and caudomedial telencephalic regions. The overall reduction in number of C-R cells in Lhx5 mutants is accompanied by formation of ectopic reelin+ cell clusters at the caudal telencephalon. Based on differential expression of molecular markers and by fluorescent cell tracing in cultured embryos, we located the origin of reelin+ ectopic cell clusters at the caudomedial telencephalic region. We also confirmed the existence of a normal migration stream of reelin+ cells from the caudomedial area to telencephalic olfactory territories in wild-type embryos. These results reveal a complex role for Lhx5 in regulating the development and normal distribution of C-R cells in the developing forebrain.
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Chowdhury TG, Jimenez JC, Bomar JM, Cruz-Martin A, Cantle JP, Portera-Cailliau C. Fate of cajal-retzius neurons in the postnatal mouse neocortex. Front Neuroanat 2010; 4:10. [PMID: 20339484 PMCID: PMC2845061 DOI: 10.3389/neuro.05.010.2010] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2009] [Accepted: 02/05/2010] [Indexed: 01/08/2023] Open
Abstract
Cajal–Retzius (CR) neurons play a critical role in cortical neuronal migration, but their exact fate after the completion of neocortical lamination remains a mystery. Histological evidence has been unable to unequivocally determine whether these cells die or undergo a phenotypic transformation to become resident interneurons of Layer 1 in the adult neocortex. To determine their ultimate fate, we performed chronic in vivo two-photon imaging of identified CR neurons during postnatal development in mice that express the green fluorescent protein (GFP) under the control of the early B-cell factor 2 (Ebf2) promoter. We find that, after birth, virtually all CR neurons in mouse neocortex express Ebf2. Although postnatal CR neurons undergo dramatic morphological transformations, they do not migrate to deeper layers. Instead, their gradual disappearance from the cortex is due to apoptotic death during the second postnatal week. A small fraction of CR neurons present at birth survive into adulthood. We conclude that, in addition to orchestrating cortical layering, a subset of CR neurons must play other roles beyond the third postnatal week.
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Affiliation(s)
- Tara G Chowdhury
- Department of Neurology, David Geffen School of Medicine at UCLA Los Angeles, CA, USA
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Morte B, Díez D, Ausó E, Belinchón MM, Gil-Ibáñez P, Grijota-Martínez C, Navarro D, de Escobar GM, Berbel P, Bernal J. Thyroid hormone regulation of gene expression in the developing rat fetal cerebral cortex: prominent role of the Ca2+/calmodulin-dependent protein kinase IV pathway. Endocrinology 2010; 151:810-20. [PMID: 20056827 DOI: 10.1210/en.2009-0958] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Thyroid hormones influence brain development through regulation of gene expression mediated by nuclear receptors. Nuclear receptor concentration increases rapidly in the human fetus during the second trimester, a period of high sensitivity of the brain to thyroid hormones. In the rat, the equivalent period is the last quarter of pregnancy. However, little is known about thyroid hormone action in the fetal brain, and in rodents, most thyroid hormone-regulated genes have been identified during the postnatal period. To identify potential targets of thyroid hormone in the fetal brain, we induced maternal and fetal hypothyroidism by maternal thyroidectomy followed by antithyroid drug (2-mercapto-1-methylimidazole) treatment. Microarray analysis identified differentially expressed genes in the cerebral cortex of hypothyroid fetuses on d 21 after conception. Gene function analysis revealed genes involved in the biogenesis of the cytoskeleton, neuronal migration and growth, and branching of neurites. Twenty percent of the differentially expressed genes were related to each other centered on the Ca(2+) and calmodulin-activated kinase (Camk4) pathway. Camk4 was regulated directly by T(3) in primary cultured neurons from fetal cortex, and the Camk4 protein was also induced by thyroid hormone. No differentially expressed genes were recovered when euthyroid fetuses from hypothyroid mothers were compared with fetuses from normal mothers. Although the results do not rule out a specific contribution from the mother, especially at earlier stages of pregnancy, they indicate that the main regulators of thyroid hormone-dependent, fetal brain gene expression near term are the fetal thyroid hormones.
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Affiliation(s)
- Beatriz Morte
- Instituto de Investigaciones Biomédicas, Consejo Superior de Investigaciones Científicas (CSIC)-Universidad Autónoma de Madrid (UAM), Madrid, Spain
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Ceci ML, López-Mascaraque L, de Carlos JA. The influence of the environment on Cajal-Retzius cell migration. ACTA ACUST UNITED AC 2010; 20:2348-60. [PMID: 20100897 DOI: 10.1093/cercor/bhp305] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
During cerebral cortex development, different cell populations migrate tangentially through the preplate, traveling from their site of origin toward their final positions. One of the earliest populations formed, the Cajal-Retzius (C-R) cells, is mainly generated in different cortical hem (CH) domains, and they migrate along established and parallel routes to cover the whole cortical mantle. In this study, we present evidence that the phenotype of -Retzius cells, as well as some of their migratory characteristics, is specified in the area where the cells are generated. Nevertheless, when implanted ectopically, these cells can follow new migratory routes, indicating that locally provided genetic cues along the migratory path nonautonomously influence the position of these cells emanating from different portions of the CH. This was witnessed by performing CH implants of tissue expressing fluorescent tracers in live whole embryos. In the same way, tracer injections into the hem of Small eye mutant mice were particularly informative since the lack of Pax6 affects some guidance factors in the migratory environment. As a result, in these animals, the C-R cell population is disorganized, and it forms 1 day late, showing certain differences in gene expression that might help explain these disruptions.
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Affiliation(s)
- María Laura Ceci
- Instituto Cajal Consejo Superior de Investigaciones Científicas, Madrid 28002, Spain
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Abellan A, Menuet A, Dehay C, Medina L, Rétaux S. Differential expression of LIM-homeodomain factors in Cajal-Retzius cells of primates, rodents, and birds. Cereb Cortex 2009; 20:1788-98. [PMID: 19923199 DOI: 10.1093/cercor/bhp242] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Reelin-expressing Cajal-Retzius (CR) cells are among the earliest generated cells in the mammalian cerebral cortex and are believed to be crucial for both the development and the evolution of a laminated pattern in the pallial wall of the telencephalon. LIM-homeodomain (LIM-hd) transcription factors are expressed during brain development in a highly restricted and combinatorial manner, and they specify regional and cellular identity. We have investigated the expression of the LIM-hd members Lhx1/Lhx2/Lhx5/Lhx6/Lhx9 in the reelin-expressing cells, the pallium, and the regions of origin of CR cells including the cortical hem of 3 amniote species: the mouse, the chick, and the macaque monkey. We found major differences in the combinatorial LIM-hd expression in the marginal zone as well as in the hem. 1) Lhx5 is a "preferential LIM-hd" for CR cells in mammals but not expressed by these cells in chicks. 2) Lhx2 is expressed in the hem of the chick, whereas it is excluded from this region in mouse. 3) Whereas mouse CR cells express Lhx5/Lhx1, their monkey counterparts express 4 of these factors: Lhx1/Lhx2/Lhx5/Lhx9. We discuss our findings in evolutionary terms for the specification of the midline hem and CR cell type and the emergence of the cortical lamination pattern.
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Affiliation(s)
- Antonio Abellan
- Laboratory of Brain Development and Evolution, Department of Experimental Medicine, Faculty of Medicine, University of Lleida, Institute of Biomedical Research of Lleida, 25008 Lleida, Spain
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Espinosa A, Gil-Sanz C, Yanagawa Y, Fairén A. Two separate subtypes of early non-subplate projection neurons in the developing cerebral cortex of rodents. Front Neuroanat 2009; 3:27. [PMID: 19949463 PMCID: PMC2784044 DOI: 10.3389/neuro.05.027.2009] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2009] [Accepted: 11/04/2009] [Indexed: 11/13/2022] Open
Abstract
The preplate of the cerebral cortex contains projection neurons that connect the cortical primordium with the subpallium. These are collectively named pioneer neurons. After preplate partition, most of these pioneer neurons become subplate neurons. Certain preplate neurons, however, never associate with the subplate but rather with the marginal zone. In the present overview, we propose a novel classification of non-subplate pioneer neurons in rodents into two subtypes. In rats, the neurons of the first subtype are calbindin+ (CB), calretinin+ (CR) and L1+ and are situated in the upper part of the preplate before its partition. Neurons of the second subtype are TAG-1+ and are located slightly deeper to the previous population in the preplate. After the preplate partition, the CB+, CR+ and L1+ neurons remain in the marginal zone whereas TAG-1+ neurons become transiently localized in the upper cortical plate. In mice, by contrast, calcium binding proteins did not label pioneer neurons. We define in mice two subtypes of non-subplate pioneer neurons, either L1+ or TAG-1+/cntn2+. We propose these to be the homologues of the two subtypes of non-subplate pioneer neurons of rats. The anatomical distribution of these neuron populations is similar in rats and mice. The two populations of non-subplate pioneer neurons differ in their axonal projections. Axons of L1+ pioneer neurons project to the ganglionic eminences and the anterior preoptic area, but avoid entering the posterior limb of the internal capsule towards the thalamus. Axons of TAG-1+ pioneer neurons project to the lateral parts of the ganglionic eminences at the early stages of cortical histogenesis examined.
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Affiliation(s)
- Ana Espinosa
- Instituto de Neurociencias, Consejo Superior de Investigaciones Científicas - Universidad Miguel Hernández San Juan de Alicante, Spain
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Karsten SL, Kudo LC, Geschwind DH. Gene expression analysis of neural cells and tissues using DNA microarrays. ACTA ACUST UNITED AC 2009; Chapter 4:Unit 4.28. [PMID: 18972379 DOI: 10.1002/0471142301.ns0428s45] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
DNA microarrays pose specific challenges to those studying the central and peripheral nervous systems. Probably the most important involve difficulty in obtaining appropriate tissue for study, as well as the problems posed by cellular heterogeneity. This unit describes advances in the available technologies and provides protocols for cDNA microarray hybridization, including the use of PCR amplicons. Protocols are also provided for the two major methods for limiting cellular heterogeneity by study of RNA from single cell populations in high-throughput microarray studies, laser capture microdissection (LCM), and automated fluorescent cell sorting (FACS-array).
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Gli3 is required autonomously for dorsal telencephalic cells to adopt appropriate fates during embryonic forebrain development. Dev Biol 2008; 327:204-15. [PMID: 19121302 DOI: 10.1016/j.ydbio.2008.12.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2008] [Revised: 12/09/2008] [Accepted: 12/10/2008] [Indexed: 01/07/2023]
Abstract
The Gli3 zinc finger transcription factor is expressed in developing forebrain, with the highest levels of expression in dorsal telencephalon. In Gli3(-/-) embryos the dorsal telencephalon is abnormally small and fails to develop dorsomedial telencephalic structures, including hippocampus and cortical hem, while the ventral telencephalon appears to expand. A hurdle to understanding the underlying mechanisms is that abnormalities of developing Gli3(-/-) telencephalic cells in Gli3(-/-) mutants result from a combination of their own cell autonomous defects and defects in the Gli3(-/-) cells that surround them. Here we used chimeras to identify some of the defects of Gli3(-/-) telencephalic cells that are likely to be autonomous by studying how Gli3(-/-) cells develop when surrounded by a majority of wild-type cells. We found that Gli3(-/-) cells are present in all components of the Gli3(-/-)<-->Gli3(+/+) chimeric forebrain, including dorsomedial structures, in proportions that either equal or exceed proportions found elsewhere in the embryo. Gli3(-/-) cells segregate from Gli3(+/+) cells to form many abnormal structures particularly in dorsal telencephalon. Gli3(-/-) cells in some locations are misspecified: in those parts of the dorsal telencephalon near to its boundaries with the diencephalon and the ventral telencephalon, mutant cells express sets of transcription factors expressed by wild-type cells on the other side of the boundary. Elsewhere in the dorsal telencephalon, in the diencephalon and in the ventral telencephalon, mutant cells express sets of transcription factors similar to those expressed by their immediately surrounding wild-type cells. We propose that an important cell autonomous action of Gli3 is to regulate the competence of dorsal telencephalic cells, preventing cells near to its boundaries expressing regulatory factors normally restricted to adjacent tissues.
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