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Puglisi M, Lao CL, Wani G, Masserdotti G, Bocchi R, Götz M. Comparing Viral Vectors and Fate Mapping Approaches for Astrocyte-to-Neuron Reprogramming in the Injured Mouse Cerebral Cortex. Cells 2024; 13:1408. [PMID: 39272980 DOI: 10.3390/cells13171408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2024] [Revised: 08/16/2024] [Accepted: 08/20/2024] [Indexed: 09/15/2024] Open
Abstract
Direct neuronal reprogramming is a promising approach to replace neurons lost due to disease via the conversion of endogenous glia reacting to brain injury into neurons. However, it is essential to demonstrate that the newly generated neurons originate from glial cells and/or show that they are not pre-existing endogenous neurons. Here, we use controls for both requirements while comparing two viral vector systems (Mo-MLVs and AAVs) for the expression of the same neurogenic factor, the phosphorylation-resistant form of Neurogenin2. Our results show that Mo-MLVs targeting proliferating glial cells after traumatic brain injury reliably convert astrocytes into neurons, as assessed by genetic fate mapping of astrocytes. Conversely, expressing the same neurogenic factor in a flexed AAV system results in artefactual labelling of endogenous neurons fatemapped by birthdating in development that are negative for the genetic fate mapping marker induced in astrocytes. These results are further corroborated by chronic live in vivo imaging. Taken together, the phosphorylation-resistant form of Neurogenin2 is more efficient in reprogramming reactive glia into neurons than its wildtype counterpart in vivo using retroviral vectors (Mo-MLVs) targeting proliferating glia. Conversely, AAV-mediated expression generates artefacts and is not sufficient to achieve fate conversion.
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Affiliation(s)
- Matteo Puglisi
- Division of Physiological Genomics, Biomedical Center, Ludwig-Maximilians-Universität München, 82152 Planegg-Martinsried, Germany
- Institute for Stem Cell Research, Helmholtz Zentrum München Deutsches Forschungszentrum für Gesundheit und Umwelt (GmbH), 85764 Nuremberg, Germany
- Graduate School of Systemic Neuroscience, Biomedical Center, Ludwig-Maximilians-Universität München, 82152 Planegg-Martinsried, Germany
| | - Chu Lan Lao
- Division of Physiological Genomics, Biomedical Center, Ludwig-Maximilians-Universität München, 82152 Planegg-Martinsried, Germany
- Institute for Stem Cell Research, Helmholtz Zentrum München Deutsches Forschungszentrum für Gesundheit und Umwelt (GmbH), 85764 Nuremberg, Germany
- Munich Cluster for Systems Neurology (SyNergy), Biomedical Center, Ludwig-Maximilians-Universität München, 82152 Planegg-Martinsried, Germany
| | - Gulzar Wani
- Division of Physiological Genomics, Biomedical Center, Ludwig-Maximilians-Universität München, 82152 Planegg-Martinsried, Germany
- Institute for Stem Cell Research, Helmholtz Zentrum München Deutsches Forschungszentrum für Gesundheit und Umwelt (GmbH), 85764 Nuremberg, Germany
| | - Giacomo Masserdotti
- Division of Physiological Genomics, Biomedical Center, Ludwig-Maximilians-Universität München, 82152 Planegg-Martinsried, Germany
- Institute for Stem Cell Research, Helmholtz Zentrum München Deutsches Forschungszentrum für Gesundheit und Umwelt (GmbH), 85764 Nuremberg, Germany
| | - Riccardo Bocchi
- Division of Physiological Genomics, Biomedical Center, Ludwig-Maximilians-Universität München, 82152 Planegg-Martinsried, Germany
- Institute for Stem Cell Research, Helmholtz Zentrum München Deutsches Forschungszentrum für Gesundheit und Umwelt (GmbH), 85764 Nuremberg, Germany
| | - Magdalena Götz
- Division of Physiological Genomics, Biomedical Center, Ludwig-Maximilians-Universität München, 82152 Planegg-Martinsried, Germany
- Institute for Stem Cell Research, Helmholtz Zentrum München Deutsches Forschungszentrum für Gesundheit und Umwelt (GmbH), 85764 Nuremberg, Germany
- Munich Cluster for Systems Neurology (SyNergy), Biomedical Center, Ludwig-Maximilians-Universität München, 82152 Planegg-Martinsried, Germany
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2
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Gasperoni JG, Tran SC, Grommen SVH, De Groef B, Dworkin S. The Role of PLAG1 in Mouse Brain Development and Neurogenesis. Mol Neurobiol 2024; 61:5851-5867. [PMID: 38240991 PMCID: PMC11249490 DOI: 10.1007/s12035-024-03943-w] [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: 09/07/2023] [Accepted: 01/10/2024] [Indexed: 07/16/2024]
Abstract
The pleomorphic adenoma gene 1 (Plag1) is a transcription factor involved in the regulation of growth and cellular proliferation. Here, we report the spatial distribution and functional implications of PLAG1 expression in the adult mouse brain. We identified Plag1 promoter-dependent β-galactosidase expression in various brain structures, including the hippocampus, cortex, choroid plexus, subcommisural organ, ependymal cells lining the third ventricle, medial and lateral habenulae and amygdala. We noted striking spatial-restriction of PLAG1 within the cornu ammonis (CA1) region of the hippocampus and layer-specific cortical expression, with abundant expression noted in all layers except layer 5. Furthermore, our study delved into the role of PLAG1 in neurodevelopment, focusing on its impact on neural stem/progenitor cell proliferation. Loss of Plag1 resulted in reduced proliferation and decreased production of neocortical progenitors in vivo, although ex vivo neurosphere experiments revealed no cell-intrinsic defects in the proliferative or neurogenic capacity of Plag1-deficient neural progenitors. Lastly, we explored potential target genes of PLAG1 in the cortex, identifying that Neurogenin 2 (Ngn2) was significantly downregulated in Plag1-deficient mice. In summary, our study provides novel insights into the spatial distribution of PLAG1 expression in the adult mouse brain and its potential role in neurodevelopment. These findings expand our understanding of the functional significance of PLAG1 within the brain, with potential implications for neurodevelopmental disorders and therapeutic interventions.
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Affiliation(s)
- Jemma G Gasperoni
- Department of Microbiology, Anatomy, Physiology and Pharmacology, School of Agriculture, Biomedicine and Environment, La Trobe University, Bundoora, Victoria, 3086, Australia
| | - Stephanie C Tran
- Department of Microbiology, Anatomy, Physiology and Pharmacology, School of Agriculture, Biomedicine and Environment, La Trobe University, Bundoora, Victoria, 3086, Australia
| | - Sylvia V H Grommen
- Department of Microbiology, Anatomy, Physiology and Pharmacology, School of Agriculture, Biomedicine and Environment, La Trobe University, Bundoora, Victoria, 3086, Australia
- Department of Biology, KU Leuven, B3000, Leuven, Belgium
| | - Bert De Groef
- Department of Microbiology, Anatomy, Physiology and Pharmacology, School of Agriculture, Biomedicine and Environment, La Trobe University, Bundoora, Victoria, 3086, Australia
- Department of Biology, KU Leuven, B3000, Leuven, Belgium
| | - Sebastian Dworkin
- Department of Microbiology, Anatomy, Physiology and Pharmacology, School of Agriculture, Biomedicine and Environment, La Trobe University, Bundoora, Victoria, 3086, Australia.
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3
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Pereira A, Diwakar J, Masserdotti G, Beşkardeş S, Simon T, So Y, Martín-Loarte L, Bergemann F, Vasan L, Schauer T, Danese A, Bocchi R, Colomé-Tatché M, Schuurmans C, Philpott A, Straub T, Bonev B, Götz M. Direct neuronal reprogramming of mouse astrocytes is associated with multiscale epigenome remodeling and requires Yy1. Nat Neurosci 2024; 27:1260-1273. [PMID: 38956165 PMCID: PMC11239498 DOI: 10.1038/s41593-024-01677-5] [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: 09/16/2022] [Accepted: 05/10/2024] [Indexed: 07/04/2024]
Abstract
Direct neuronal reprogramming is a promising approach to regenerate neurons from local glial cells. However, mechanisms of epigenome remodeling and co-factors facilitating this process are unclear. In this study, we combined single-cell multiomics with genome-wide profiling of three-dimensional nuclear architecture and DNA methylation in mouse astrocyte-to-neuron reprogramming mediated by Neurogenin2 (Ngn2) and its phosphorylation-resistant form (PmutNgn2), respectively. We show that Ngn2 drives multilayered chromatin remodeling at dynamic enhancer-gene interaction sites. PmutNgn2 leads to higher reprogramming efficiency and enhances epigenetic remodeling associated with neuronal maturation. However, the differences in binding sites or downstream gene activation cannot fully explain this effect. Instead, we identified Yy1, a transcriptional co-factor recruited by direct interaction with Ngn2 to its target sites. Upon deletion of Yy1, activation of neuronal enhancers, genes and ultimately reprogramming are impaired without affecting Ngn2 binding. Thus, our work highlights the key role of interactors of proneural factors in direct neuronal reprogramming.
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Affiliation(s)
- Allwyn Pereira
- Biomedical Center Munich (BMC), Physiological Genomics, LMU Munich, Planegg, Germany
- Institute of Stem Cell Research, Helmholtz Center Munich, BMC LMU Munich, Planegg, Germany
- Nantes Université, CHU Nantes, INSERM, TaRGeT - Translational Research in Gene Therapy, UMR 1089, Nantes, France
| | - Jeisimhan Diwakar
- Biomedical Center Munich (BMC), Physiological Genomics, LMU Munich, Planegg, Germany
- Helmholtz Pioneer Campus, Helmholtz Center Munich, Neuherberg, Germany
| | - Giacomo Masserdotti
- Biomedical Center Munich (BMC), Physiological Genomics, LMU Munich, Planegg, Germany
- Institute of Stem Cell Research, Helmholtz Center Munich, BMC LMU Munich, Planegg, Germany
| | - Sude Beşkardeş
- Biomedical Center Munich (BMC), Physiological Genomics, LMU Munich, Planegg, Germany
- Helmholtz Pioneer Campus, Helmholtz Center Munich, Neuherberg, Germany
| | - Tatiana Simon
- Biomedical Center Munich (BMC), Physiological Genomics, LMU Munich, Planegg, Germany
- Institute of Stem Cell Research, Helmholtz Center Munich, BMC LMU Munich, Planegg, Germany
| | - Younju So
- Biomedical Center Munich (BMC), Physiological Genomics, LMU Munich, Planegg, Germany
- Institute of Stem Cell Research, Helmholtz Center Munich, BMC LMU Munich, Planegg, Germany
| | - Lucía Martín-Loarte
- Biomedical Center Munich (BMC), Physiological Genomics, LMU Munich, Planegg, Germany
- Institute of Stem Cell Research, Helmholtz Center Munich, BMC LMU Munich, Planegg, Germany
| | - Franziska Bergemann
- Biomedical Center Munich (BMC), Physiological Genomics, LMU Munich, Planegg, Germany
- Institute of Stem Cell Research, Helmholtz Center Munich, BMC LMU Munich, Planegg, Germany
| | - Lakshmy Vasan
- Biological Science Platform, Sunnybrook Research Institute; Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Tamas Schauer
- Biomedical Center Munich (BMC), Bioinformatic Core Facility, Faculty of Medicine, LMU Munich, Planegg, Germany
- Institute of Stem Cells and Epigenetics, Helmholtz Center Munich, Neuherberg, Germany
| | - Anna Danese
- Biomedical Center Munich (BMC), Physiological Genomics, LMU Munich, Planegg, Germany
- Institute of Stem Cell Research, Helmholtz Center Munich, BMC LMU Munich, Planegg, Germany
| | - Riccardo Bocchi
- Biomedical Center Munich (BMC), Physiological Genomics, LMU Munich, Planegg, Germany
- Institute of Stem Cell Research, Helmholtz Center Munich, BMC LMU Munich, Planegg, Germany
- Department of Basic Neurosciences, University of Geneva, Geneva, Switzerland
| | - Maria Colomé-Tatché
- Institute of Computational Biology, Helmholtz Center Munich, Neuherberg, Germany
- Biomedical Center Munich (BMC), Physiological Chemistry, Faculty of Medicine, LMU Munich, Planegg, Germany
| | - Carol Schuurmans
- Biological Science Platform, Sunnybrook Research Institute; Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Anna Philpott
- Wellcome-Medical Research Council Cambridge Stem Cell Institute, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK
| | - Tobias Straub
- Biological Science Platform, Sunnybrook Research Institute; Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Boyan Bonev
- Biomedical Center Munich (BMC), Physiological Genomics, LMU Munich, Planegg, Germany.
- Helmholtz Pioneer Campus, Helmholtz Center Munich, Neuherberg, Germany.
| | - Magdalena Götz
- Biomedical Center Munich (BMC), Physiological Genomics, LMU Munich, Planegg, Germany.
- Institute of Stem Cell Research, Helmholtz Center Munich, BMC LMU Munich, Planegg, Germany.
- Excellence Cluster of Systems Neurology (SYNERGY), Munich, Germany.
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4
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Wei J, Wang M, Li S, Han R, Xu W, Zhao A, Yu Q, Li H, Li M, Chi G. Reprogramming of astrocytes and glioma cells into neurons for central nervous system repair and glioblastoma therapy. Biomed Pharmacother 2024; 176:116806. [PMID: 38796971 DOI: 10.1016/j.biopha.2024.116806] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2024] [Revised: 05/18/2024] [Accepted: 05/20/2024] [Indexed: 05/29/2024] Open
Abstract
Central nervous system (CNS) damage is usually irreversible owing to the limited regenerative capability of neurons. Following CNS injury, astrocytes are reactively activated and are the key cells involved in post-injury repair mechanisms. Consequently, research on the reprogramming of reactive astrocytes into neurons could provide new directions for the restoration of neural function after CNS injury and in the promotion of recovery in various neurodegenerative diseases. This review aims to provide an overview of the means through which reactive astrocytes around lesions can be reprogrammed into neurons, to elucidate the intrinsic connection between the two cell types from a neurogenesis perspective, and to summarize what is known about the neurotranscription factors, small-molecule compounds and MicroRNA that play major roles in astrocyte reprogramming. As the malignant proliferation of astrocytes promotes the development of glioblastoma multiforme (GBM), this review also examines the research advances on and the theoretical basis for the reprogramming of GBM cells into neurons and discusses the advantages of such approaches over traditional treatment modalities. This comprehensive review provides new insights into the field of GBM therapy and theoretical insights into the mechanisms of neurological recovery following neurological injury and in GBM treatment.
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Affiliation(s)
- Junyuan Wei
- The Key Laboratory of Pathobiology, Ministry of Education, and College of Basic Medical Sciences, Jilin University, Changchun 130021, China.
| | - Miaomiao Wang
- The Key Laboratory of Pathobiology, Ministry of Education, and College of Basic Medical Sciences, Jilin University, Changchun 130021, China.
| | - Shilin Li
- School of Public Health, Jilin University, Changchun 130021, China.
| | - Rui Han
- Department of Neurovascular Surgery, First Hospital of Jilin University, 1xinmin Avenue, Changchun, Jilin Province 130021, China.
| | - Wenhong Xu
- The Key Laboratory of Pathobiology, Ministry of Education, and College of Basic Medical Sciences, Jilin University, Changchun 130021, China.
| | - Anqi Zhao
- The Key Laboratory of Pathobiology, Ministry of Education, and College of Basic Medical Sciences, Jilin University, Changchun 130021, China.
| | - Qi Yu
- The Key Laboratory of Pathobiology, Ministry of Education, and College of Basic Medical Sciences, Jilin University, Changchun 130021, China.
| | - Haokun Li
- The Key Laboratory of Pathobiology, Ministry of Education, and College of Basic Medical Sciences, Jilin University, Changchun 130021, China.
| | - Meiying Li
- The Key Laboratory of Pathobiology, Ministry of Education, and College of Basic Medical Sciences, Jilin University, Changchun 130021, China.
| | - Guangfan Chi
- The Key Laboratory of Pathobiology, Ministry of Education, and College of Basic Medical Sciences, Jilin University, Changchun 130021, China.
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5
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Foucault L, Capeliez T, Angonin D, Lentini C, Bezin L, Heinrich C, Parras C, Donega V, Marcy G, Raineteau O. Neonatal brain injury unravels transcriptional and signaling changes underlying the reactivation of cortical progenitors. Cell Rep 2024; 43:113734. [PMID: 38349790 DOI: 10.1016/j.celrep.2024.113734] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 11/03/2023] [Accepted: 01/16/2024] [Indexed: 02/15/2024] Open
Abstract
Germinal activity persists throughout life within the ventricular-subventricular zone (V-SVZ) of the postnatal forebrain due to the presence of neural stem cells (NSCs). Accumulating evidence points to a recruitment for these cells following early brain injuries and suggests their amenability to manipulations. We used chronic hypoxia as a rodent model of early brain injury to investigate the reactivation of cortical progenitors at postnatal times. Our results reveal an increased proliferation and production of glutamatergic progenitors within the dorsal V-SVZ. Fate mapping of V-SVZ NSCs demonstrates their contribution to de novo cortical neurogenesis. Transcriptional analysis of glutamatergic progenitors shows parallel changes in methyltransferase 14 (Mettl14) and Wnt/β-catenin signaling. In agreement, manipulations through genetic and pharmacological activation of Mettl14 and the Wnt/β-catenin pathway, respectively, induce neurogenesis and promote newly-formed cell maturation. Finally, labeling of young adult NSCs demonstrates that pharmacological NSC activation has no adverse effects on the reservoir of V-SVZ NSCs and on their germinal activity.
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Affiliation(s)
- Louis Foucault
- University Lyon, Université Claude Bernard Lyon1, INSERM, Stem Cell and Brain Research Institute U1208, 69500 Bron, France.
| | - Timothy Capeliez
- University Lyon, Université Claude Bernard Lyon1, INSERM, Stem Cell and Brain Research Institute U1208, 69500 Bron, France
| | - Diane Angonin
- University Lyon, Université Claude Bernard Lyon1, INSERM, Stem Cell and Brain Research Institute U1208, 69500 Bron, France
| | - Celia Lentini
- University Lyon, Université Claude Bernard Lyon1, INSERM, Stem Cell and Brain Research Institute U1208, 69500 Bron, France
| | - Laurent Bezin
- University Lyon, Université Claude Bernard Lyon 1, INSERM, Centre de Recherche en Neuroscience de Lyon U1028 - CNRS UMR5292, 69500 Bron, France
| | - Christophe Heinrich
- University Lyon, Université Claude Bernard Lyon1, INSERM, Stem Cell and Brain Research Institute U1208, 69500 Bron, France
| | - Carlos Parras
- Paris Brain Institute, Sorbonne Université, INSERM U1127, CNRS UMR 7225, Hôpital Pitié-Salpêtrière, 75013 Paris, France
| | - Vanessa Donega
- University Lyon, Université Claude Bernard Lyon1, INSERM, Stem Cell and Brain Research Institute U1208, 69500 Bron, France; Amsterdam Neuroscience, Cellular and Molecular Mechanisms, Amsterdam, the Netherlands
| | - Guillaume Marcy
- University Lyon, Université Claude Bernard Lyon1, INSERM, Stem Cell and Brain Research Institute U1208, 69500 Bron, France
| | - Olivier Raineteau
- University Lyon, Université Claude Bernard Lyon1, INSERM, Stem Cell and Brain Research Institute U1208, 69500 Bron, France.
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6
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Lu C, Garipler G, Dai C, Roush T, Salome-Correa J, Martin A, Liscovitch-Brauer N, Mazzoni EO, Sanjana NE. Essential transcription factors for induced neuron differentiation. Nat Commun 2023; 14:8362. [PMID: 38102126 PMCID: PMC10724217 DOI: 10.1038/s41467-023-43602-7] [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: 08/16/2023] [Accepted: 11/14/2023] [Indexed: 12/17/2023] Open
Abstract
Neurogenins are proneural transcription factors required to specify neuronal identity. Their overexpression in human pluripotent stem cells rapidly produces cortical-like neurons with spiking activity and, because of this, they have been widely adopted for human neuron disease models. However, we do not fully understand the key downstream regulatory effectors responsible for driving neural differentiation. Here, using inducible expression of NEUROG1 and NEUROG2, we identify transcription factors (TFs) required for directed neuronal differentiation by combining expression and chromatin accessibility analyses with a pooled in vitro CRISPR-Cas9 screen targeting all ~1900 TFs in the human genome. The loss of one of these essential TFs (ZBTB18) yields few MAP2-positive neurons. Differentiated ZBTB18-null cells have radically altered gene expression, leading to cytoskeletal defects and stunted neurites and spines. In addition to identifying key downstream TFs for neuronal differentiation, our work develops an integrative multi-omics and TFome-wide perturbation platform to rapidly characterize essential TFs for the differentiation of any human cell type.
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Affiliation(s)
- Congyi Lu
- New York Genome Center, New York, NY, USA
- Department of Biology, New York University, New York, NY, USA
| | - Görkem Garipler
- Department of Biology, New York University, New York, NY, USA
| | - Chao Dai
- New York Genome Center, New York, NY, USA
- Department of Biology, New York University, New York, NY, USA
| | - Timothy Roush
- New York Genome Center, New York, NY, USA
- Department of Biology, New York University, New York, NY, USA
| | - Jose Salome-Correa
- New York Genome Center, New York, NY, USA
- Department of Biology, New York University, New York, NY, USA
| | - Alex Martin
- New York Genome Center, New York, NY, USA
- Department of Biology, New York University, New York, NY, USA
| | - Noa Liscovitch-Brauer
- New York Genome Center, New York, NY, USA
- Department of Biology, New York University, New York, NY, USA
| | - Esteban O Mazzoni
- Department of Biology, New York University, New York, NY, USA.
- Department of Cell Biology, NYU Grossman School of Medicine, New York, NY, USA.
| | - Neville E Sanjana
- New York Genome Center, New York, NY, USA.
- Department of Biology, New York University, New York, NY, USA.
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7
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Péron S, Miyakoshi LM, Brill MS, Manzano-Franco D, Serrano-López J, Fan W, Marichal N, Ghanem A, Conzelmann KK, Karow M, Ortega F, Gascón S, Berninger B. Programming of neural progenitors of the adult subependymal zone towards a glutamatergic neuron lineage by neurogenin 2. Stem Cell Reports 2023; 18:2418-2433. [PMID: 37995703 PMCID: PMC10724369 DOI: 10.1016/j.stemcr.2023.10.019] [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: 08/21/2021] [Revised: 10/26/2023] [Accepted: 10/27/2023] [Indexed: 11/25/2023] Open
Abstract
Although adult subependymal zone (SEZ) neural stem cells mostly generate GABAergic interneurons, a small progenitor population expresses the proneural gene Neurog2 and produces glutamatergic neurons. Here, we determined whether Neurog2 could respecify SEZ neural stem cells and their progeny toward a glutamatergic fate. Retrovirus-mediated expression of Neurog2 induced the glutamatergic lineage markers TBR2 and TBR1 in cultured SEZ progenitors, which differentiated into functional glutamatergic neurons. Likewise, Neurog2-transduced SEZ progenitors acquired glutamatergic neuron hallmarks in vivo. Intriguingly, they failed to migrate toward the olfactory bulb and instead differentiated within the SEZ or the adjacent striatum, where they received connections from local neurons, as indicated by rabies virus-mediated monosynaptic tracing. In contrast, lentivirus-mediated expression of Neurog2 failed to reprogram early SEZ neurons, which maintained GABAergic identity and migrated to the olfactory bulb. Our data show that NEUROG2 can program SEZ progenitors toward a glutamatergic identity but fails to reprogram their neuronal progeny.
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Affiliation(s)
- Sophie Péron
- Research Group "Adult Neurogenesis and Cellular Reprogramming", Institute of Physiological Chemistry, University Medical Center Johannes Gutenberg University, Mainz, Germany; Centre for Developmental Neurobiology, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Leo M Miyakoshi
- Physiological Genomics, Institute of Physiology, Ludwig-Maximilians University Munich, Munich, Germany
| | - Monika S Brill
- Institute of Neuronal Cell Biology, Technical University Munich, Munich, Germany; Munich Cluster of Systems Neurology (SyNergy), Munich, Germany
| | - Diana Manzano-Franco
- Department of Molecular, Cellular and Developmental Neurobiology, Cajal Institute - CSIC, Madrid, Spain
| | - Julia Serrano-López
- Department of Biochemistry and Molecular Biology, Faculty of Veterinary, Universidad Complutense de Madrid (UCM), Madrid, Spain; Instituto Universitario de Investigación en Neuroquímica (IUIN), Madrid, Spain; Instituto de Investigación Sanitaria San Carlos (IdISSC), Madrid, Spain
| | - Wenqiang Fan
- Research Group "Adult Neurogenesis and Cellular Reprogramming", Institute of Physiological Chemistry, University Medical Center Johannes Gutenberg University, Mainz, Germany
| | - Nicolás Marichal
- Centre for Developmental Neurobiology, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Alexander Ghanem
- Max von Pettenkofer Institute and Gene Center, Ludwig Maximilians-University Munich, Munich, Germany
| | - Karl-Klaus Conzelmann
- Max von Pettenkofer Institute and Gene Center, Ludwig Maximilians-University Munich, Munich, Germany
| | - Marisa Karow
- Institute of Biochemistry, Friedrich-Alexander Universität Nürnberg-Erlangen, Erlangen, Germany
| | - Felipe Ortega
- Department of Biochemistry and Molecular Biology, Faculty of Veterinary, Universidad Complutense de Madrid (UCM), Madrid, Spain; Instituto Universitario de Investigación en Neuroquímica (IUIN), Madrid, Spain; Instituto de Investigación Sanitaria San Carlos (IdISSC), Madrid, Spain
| | - Sergio Gascón
- Department of Molecular, Cellular and Developmental Neurobiology, Cajal Institute - CSIC, Madrid, Spain.
| | - Benedikt Berninger
- Research Group "Adult Neurogenesis and Cellular Reprogramming", Institute of Physiological Chemistry, University Medical Center Johannes Gutenberg University, Mainz, Germany; Centre for Developmental Neurobiology, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK; MRC Centre for Neurodevelopmental Disorders, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK; Focus Program Translational Neurosciences, Johannes Gutenberg University, Mainz, Germany.
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8
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Fang YM, Chen WC, Zheng WJ, Yang YS, Zhang Y, Chen XL, Pei MQ, Lin S, He HF. A cutting-edge strategy for spinal cord injury treatment: resident cellular transdifferentiation. Front Cell Neurosci 2023; 17:1237641. [PMID: 37711511 PMCID: PMC10498389 DOI: 10.3389/fncel.2023.1237641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Accepted: 08/14/2023] [Indexed: 09/16/2023] Open
Abstract
Spinal cord injury causes varying degrees of motor and sensory function loss. However, there are no effective treatments for spinal cord repair following an injury. Moreover, significant preclinical advances in bioengineering and regenerative medicine have not yet been translated into effective clinical therapies. The spinal cord's poor regenerative capacity makes repairing damaged and lost neurons a critical treatment step. Reprogramming-based neuronal transdifferentiation has recently shown great potential in repair and plasticity, as it can convert mature somatic cells into functional neurons for spinal cord injury repair in vitro and in vivo, effectively halting the progression of spinal cord injury and promoting functional improvement. However, the mechanisms of the neuronal transdifferentiation and the induced neuronal subtypes are not yet well understood. This review analyzes the mechanisms of resident cellular transdifferentiation based on a review of the relevant recent literature, describes different molecular approaches to obtain different neuronal subtypes, discusses the current challenges and improvement methods, and provides new ideas for exploring therapeutic approaches for spinal cord injury.
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Affiliation(s)
- Yu-Ming Fang
- Department of Anaesthesiology, The Second Affiliated Hospital of Fujian Medical University, Quanzhou, China
| | - Wei-Can Chen
- Department of Anaesthesiology, The Second Affiliated Hospital of Fujian Medical University, Quanzhou, China
| | - Wan-Jing Zheng
- Department of Anaesthesiology, The Second Affiliated Hospital of Fujian Medical University, Quanzhou, China
| | - Yu-Shen Yang
- Department of Anaesthesiology, The Second Affiliated Hospital of Fujian Medical University, Quanzhou, China
| | - Yan Zhang
- Department of Anaesthesiology, The Second Affiliated Hospital of Fujian Medical University, Quanzhou, China
| | - Xin-Li Chen
- Department of Anaesthesiology, The Second Affiliated Hospital of Fujian Medical University, Quanzhou, China
| | - Meng-Qin Pei
- Department of Anaesthesiology, The Second Affiliated Hospital of Fujian Medical University, Quanzhou, China
| | - Shu Lin
- Centre of Neurological and Metabolic Research, The Second Affiliated Hospital of Fujian Medical University, Quanzhou, China
- Neuroendocrinology Group, Garvan Institute of Medical Research, Sydney, NSW, Australia
| | - He-Fan He
- Department of Anaesthesiology, The Second Affiliated Hospital of Fujian Medical University, Quanzhou, China
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9
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Ghazale H, Park E, Vasan L, Mester J, Saleh F, Trevisiol A, Zinyk D, Chinchalongporn V, Liu M, Fleming T, Prokopchuk O, Klenin N, Kurrasch D, Faiz M, Stefanovic B, McLaurin J, Schuurmans C. Ascl1 phospho-site mutations enhance neuronal conversion of adult cortical astrocytes in vivo. Front Neurosci 2022; 16:917071. [PMID: 36061596 PMCID: PMC9434350 DOI: 10.3389/fnins.2022.917071] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2022] [Accepted: 07/25/2022] [Indexed: 11/13/2022] Open
Abstract
Direct neuronal reprogramming, the process whereby a terminally differentiated cell is converted into an induced neuron without traversing a pluripotent state, has tremendous therapeutic potential for a host of neurodegenerative diseases. While there is strong evidence for astrocyte-to-neuron conversion in vitro, in vivo studies in the adult brain are less supportive or controversial. Here, we set out to enhance the efficacy of neuronal conversion of adult astrocytes in vivo by optimizing the neurogenic capacity of a driver transcription factor encoded by the proneural gene Ascl1. Specifically, we mutated six serine phospho-acceptor sites in Ascl1 to alanines (Ascl1 SA 6) to prevent phosphorylation by proline-directed serine/threonine kinases. Native Ascl1 or Ascl1 SA 6 were expressed in adult, murine cortical astrocytes under the control of a glial fibrillary acidic protein (GFAP) promoter using adeno-associated viruses (AAVs). When targeted to the cerebral cortex in vivo, mCherry+ cells transduced with AAV8-GFAP-Ascl1 SA 6-mCherry or AAV8-GFAP-Ascl1-mCherry expressed neuronal markers within 14 days post-transduction, with Ascl1 SA 6 promoting the formation of more mature dendritic arbors compared to Ascl1. However, mCherry expression disappeared by 2-months post-transduction of the AAV8-GFAP-mCherry control-vector. To circumvent reporter issues, AAV-GFAP-iCre (control) and AAV-GFAP-Ascl1 (or Ascl1 SA 6)-iCre constructs were generated and injected into the cerebral cortex of Rosa reporter mice. In all comparisons of AAV capsids (AAV5 and AAV8), GFAP promoters (long and short), and reporter mice (Rosa-zsGreen and Rosa-tdtomato), Ascl1 SA 6 transduced cells more frequently expressed early- (Dcx) and late- (NeuN) neuronal markers. Furthermore, Ascl1 SA 6 repressed the expression of astrocytic markers Sox9 and GFAP more efficiently than Ascl1. Finally, we co-transduced an AAV expressing ChR2-(H134R)-YFP, an optogenetic actuator. After channelrhodopsin photostimulation, we found that Ascl1 SA 6 co-transduced astrocytes exhibited a significantly faster decay of evoked potentials to baseline, a neuronal feature, when compared to iCre control cells. Taken together, our findings support an enhanced neuronal conversion efficiency of Ascl1 SA 6 vs. Ascl1, and position Ascl1 SA 6 as a critical transcription factor for future studies aimed at converting adult brain astrocytes to mature neurons to treat disease.
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Affiliation(s)
- Hussein Ghazale
- Sunnybrook Research Institute, Toronto, ON, Canada
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - EunJee Park
- Sunnybrook Research Institute, Toronto, ON, Canada
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Lakshmy Vasan
- Sunnybrook Research Institute, Toronto, ON, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
| | - James Mester
- Sunnybrook Research Institute, Toronto, ON, Canada
- Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada
| | - Fermisk Saleh
- Sunnybrook Research Institute, Toronto, ON, Canada
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Andrea Trevisiol
- Sunnybrook Research Institute, Toronto, ON, Canada
- Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada
| | - Dawn Zinyk
- Sunnybrook Research Institute, Toronto, ON, Canada
| | - Vorapin Chinchalongporn
- Sunnybrook Research Institute, Toronto, ON, Canada
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Mingzhe Liu
- Sunnybrook Research Institute, Toronto, ON, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
| | - Taylor Fleming
- Sunnybrook Research Institute, Toronto, ON, Canada
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | | | - Natalia Klenin
- Department of Medical Genetics, Cumming School of Medicine, Hotchkiss Brain Institute, Alberta Children’s Hospital Research Institute, University of Calgary, Calgary, AB, Canada
| | - Deborah Kurrasch
- Department of Medical Genetics, Cumming School of Medicine, Hotchkiss Brain Institute, Alberta Children’s Hospital Research Institute, University of Calgary, Calgary, AB, Canada
| | - Maryam Faiz
- Department of Surgery, University of Toronto, Toronto, ON, Canada
| | - Bojana Stefanovic
- Sunnybrook Research Institute, Toronto, ON, Canada
- Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada
| | - JoAnne McLaurin
- Sunnybrook Research Institute, Toronto, ON, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
| | - Carol Schuurmans
- Sunnybrook Research Institute, Toronto, ON, Canada
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
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10
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Wang J, Chen S, Pan C, Li G, Tang Z. Application of Small Molecules in the Central Nervous System Direct Neuronal Reprogramming. Front Bioeng Biotechnol 2022; 10:799152. [PMID: 35875485 PMCID: PMC9301571 DOI: 10.3389/fbioe.2022.799152] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Accepted: 06/09/2022] [Indexed: 11/13/2022] Open
Abstract
The lack of regenerative capacity of neurons leads to poor prognoses for some neurological disorders. The use of small molecules to directly reprogram somatic cells into neurons provides a new therapeutic strategy for neurological diseases. In this review, the mechanisms of action of different small molecules, the approaches to screening small molecule cocktails, and the methods employed to detect their reprogramming efficiency are discussed, and the studies, focusing on neuronal reprogramming using small molecules in neurological disease models, are collected. Future research efforts are needed to investigate the in vivo mechanisms of small molecule-mediated neuronal reprogramming under pathophysiological states, optimize screening cocktails and dosing regimens, and identify safe and effective delivery routes to promote neural regeneration in different neurological diseases.
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Affiliation(s)
| | | | | | - Gaigai Li
- *Correspondence: Gaigai Li, ; Zhouping Tang,
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11
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Nomura T, Gotoh H, Kiyonari H, Ono K. Cell Type-Specific Transcriptional Control of Gsk3β in the Developing Mammalian Neocortex. Front Neurosci 2022; 16:811689. [PMID: 35401100 PMCID: PMC8983961 DOI: 10.3389/fnins.2022.811689] [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: 11/09/2021] [Accepted: 02/15/2022] [Indexed: 11/16/2022] Open
Abstract
Temporal control of neurogenesis is central for the development and evolution of species-specific brain architectures. The balance between progenitor expansion and neuronal differentiation is tightly coordinated by cell-intrinsic and cell-extrinsic cues. Wnt signaling plays pivotal roles in the proliferation and differentiation of neural progenitors in a temporal manner. However, regulatory mechanisms that adjust intracellular signaling amplitudes according to cell fate progression remain to be elucidated. Here, we report the transcriptional controls of Gsk3β, a critical regulator of Wnt signaling, in the developing mouse neocortex. Gsk3β expression was higher in ventricular neural progenitors, while it gradually declined in differentiated neurons. We identified active cis-regulatory module (CRM) of Gsk3β that responded to cell type-specific transcription factors, such as Sox2, Sox9, and Neurogenin2. Furthermore, we found extensive conservation of the CRM among mammals but not in non-mammalian amniotes. Our data suggest that a mammalian-specific CRM drives the cell type-specific activity of Gsk3β to fine tune Wnt signaling, which contributes to the tight control of neurogenesis during neocortical development.
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Affiliation(s)
- Tadashi Nomura
- Developmental Neurobiology, INAMORI Memorial Building, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Hitoshi Gotoh
- Developmental Neurobiology, INAMORI Memorial Building, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Hiroshi Kiyonari
- Laboratory for Animal Resources and Genetic Engineering, RIKEN Center for Biosystems Dynamics Research, Kobe, Japan
| | - Katsuhiko Ono
- Developmental Neurobiology, INAMORI Memorial Building, Kyoto Prefectural University of Medicine, Kyoto, Japan
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12
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ASCL1 phosphorylation and ID2 upregulation are roadblocks to glioblastoma stem cell differentiation. Sci Rep 2022; 12:2341. [PMID: 35149717 PMCID: PMC8837758 DOI: 10.1038/s41598-022-06248-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Accepted: 01/20/2022] [Indexed: 12/15/2022] Open
Abstract
The growth of glioblastoma (GBM), one of the deadliest adult cancers, is fuelled by a subpopulation of stem/progenitor cells, which are thought to be the source of resistance and relapse after treatment. Re-engagement of a latent capacity of these cells to re-enter a trajectory resulting in cell differentiation is a potential new therapeutic approach for this devastating disease. ASCL1, a proneural transcription factor, plays a key role in normal brain development and is also expressed in a subset of GBM cells, but fails to engage a full differentiation programme in this context. Here, we investigated the barriers to ASCL1-driven differentiation in GBM stem cells. We see that ASCL1 is highly phosphorylated in GBM stem cells where its expression is compatible with cell proliferation. However, overexpression of a form of ASCL1 that cannot be phosphorylated on Serine–Proline sites drives GBM cells down a neuronal lineage and out of cell cycle more efficiently than its wild-type counterpart, an effect further enhanced by deletion of the inhibitor of differentiation ID2, indicating mechanisms to reverse the block to GBM cell differentiation.
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13
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Direct neuronal reprogramming: Fast forward from new concepts toward therapeutic approaches. Neuron 2021; 110:366-393. [PMID: 34921778 DOI: 10.1016/j.neuron.2021.11.023] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 10/25/2021] [Accepted: 11/19/2021] [Indexed: 12/21/2022]
Abstract
Differentiated cells have long been considered fixed in their identity. However, about 20 years ago, the first direct conversion of glial cells into neurons in vitro opened the field of "direct neuronal reprogramming." Since then, neuronal reprogramming has achieved the generation of fully functional, mature neurons with remarkable efficiency, even in diseased brain environments. Beyond their clinical implications, these discoveries provided basic insights into crucial mechanisms underlying conversion of specific cell types into neurons and maintenance of neuronal identity. Here we discuss such principles, including the importance of the starter cell for shaping the outcome of neuronal reprogramming. We further highlight technical concerns for in vivo reprogramming and propose a code of conduct to avoid artifacts and pitfalls. We end by pointing out next challenges for development of less invasive cell replacement therapies for humans.
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14
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Zhang GY, Lv ZM, Ma HX, Chen Y, Yuan Y, Sun PX, Feng YQ, Li YW, Lu WJ, Yang YD, Yang C, Yu XL, Wang C, Liang SL, Zhang ML, Li HL, Li WL. Chemical approach to generating long-term self-renewing pMN progenitors from human embryonic stem cells. J Mol Cell Biol 2021; 14:6459209. [PMID: 34893854 PMCID: PMC8872822 DOI: 10.1093/jmcb/mjab076] [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: 06/29/2021] [Revised: 10/24/2021] [Accepted: 12/06/2021] [Indexed: 11/13/2022] Open
Abstract
Spinal cord impairment involving motor neuron degeneration and demyelination can cause life-long disabilities, but effective clinical interventions for restoring neurological functions have yet been developed. In early spinal cord development, neural progenitors in the pMN ('progenitors of motor neurons') domain, defined by the expression of oligodendrocyte transcription factor 2 (OLIG2), in ventral spinal cord first generate motor neurons and then switch the fate to produce myelin-forming oligodendrocytes. Given their differentiation potential, pMN progenitors could be a valuable cell source for cell therapy in relevant neurological conditions such as spinal cord injury. However, fast generation and expansion of pMN progenitors in vitro while conserving their differentiation potential has so far been technically challenging. In this study, based on the chemical screening, we have developed a new recipe for efficient induction of pMN progenitors from human embryonic stem cells. More importantly, these OLIG2+ pMN progenitors can be stably maintained for multiple passages without losing their ability to produce spinal motor neurons and oligodendrocytes rapidly. Our results suggest that these self-renewing pMN progenitors could potentially be useful as a renewable source of cell transplants for spinal cord injury and demyelinating disorders.
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Affiliation(s)
- Guan-Yu Zhang
- Department of Cell Biology, Second Military Medical University, Shanghai 200433, China
| | - Zhu-Man Lv
- Department of Cell Biology, Second Military Medical University, Shanghai 200433, China
| | - Hao-Xin Ma
- Department of Cell Biology, Second Military Medical University, Shanghai 200433, China
| | - Yu Chen
- Changhai Hospital, Second Military Medical University, Shanghai 200433, China
| | - Yuan Yuan
- Department of Cell Biology, Second Military Medical University, Shanghai 200433, China
| | - Ping-Xin Sun
- Department of Cell Biology, Second Military Medical University, Shanghai 200433, China
| | - Yu-Qi Feng
- Department of Cell Biology, Second Military Medical University, Shanghai 200433, China
| | - Ya-Wen Li
- Department of Histoembryology, Genetics and Developmental Biology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China.,Shanghai Key Laboratory of Reproductive Medicine, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Wen-Jie Lu
- Department of Histoembryology, Genetics and Developmental Biology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China.,Shanghai Key Laboratory of Reproductive Medicine, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Yu-Dong Yang
- Department of Histoembryology, Genetics and Developmental Biology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China.,Shanghai Key Laboratory of Reproductive Medicine, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Cheng Yang
- Wolfson Institute for Biomedical Research, University College London, Gower Street, London WC1E 6BT, UK
| | - Xin-Lu Yu
- Department of Cell Biology, Second Military Medical University, Shanghai 200433, China
| | - Chao Wang
- Department of Cell Biology, Second Military Medical University, Shanghai 200433, China
| | - Shu-Long Liang
- Department of Cell Biology, Second Military Medical University, Shanghai 200433, China
| | - Ming-Liang Zhang
- Department of Histoembryology, Genetics and Developmental Biology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China.,Shanghai Key Laboratory of Reproductive Medicine, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Hui-Liang Li
- Wolfson Institute for Biomedical Research, University College London, Gower Street, London WC1E 6BT, UK
| | - Wen-Lin Li
- Department of Cell Biology, Second Military Medical University, Shanghai 200433, China.,Shanghai Key Laboratory of Cell Engineering, Second Military Medical University, Shanghai 200433, China
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15
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Homodimeric and Heterodimeric Interactions among Vertebrate Basic Helix-Loop-Helix Transcription Factors. Int J Mol Sci 2021; 22:ijms222312855. [PMID: 34884664 PMCID: PMC8657788 DOI: 10.3390/ijms222312855] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 11/11/2021] [Accepted: 11/17/2021] [Indexed: 01/01/2023] Open
Abstract
The basic helix–loop–helix transcription factor (bHLH TF) family is involved in tissue development, cell differentiation, and disease. These factors have transcriptionally positive, negative, and inactive functions by combining dimeric interactions among family members. The best known bHLH TFs are the E-protein homodimers and heterodimers with the tissue-specific TFs or ID proteins. These cooperative and dynamic interactions result in a complex transcriptional network that helps define the cell’s fate. Here, the reported dimeric interactions of 67 vertebrate bHLH TFs with other family members are summarized in tables, including specifications of the experimental techniques that defined the dimers. The compilation of these extensive data underscores homodimers of tissue-specific bHLH TFs as a central part of the bHLH regulatory network, with relevant positive and negative transcriptional regulatory roles. Furthermore, some sequence-specific TFs can also form transcriptionally inactive heterodimers with each other. The function, classification, and developmental role for all vertebrate bHLH TFs in four major classes are detailed.
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16
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Han S, Okawa S, Wilkinson GA, Ghazale H, Adnani L, Dixit R, Tavares L, Faisal I, Brooks MJ, Cortay V, Zinyk D, Sivitilli A, Li S, Malik F, Ilnytskyy Y, Angarica VE, Gao J, Chinchalongporn V, Oproescu AM, Vasan L, Touahri Y, David LA, Raharjo E, Kim JW, Wu W, Rahmani W, Chan JAW, Kovalchuk I, Attisano L, Kurrasch D, Dehay C, Swaroop A, Castro DS, Biernaskie J, Del Sol A, Schuurmans C. Proneural genes define ground-state rules to regulate neurogenic patterning and cortical folding. Neuron 2021; 109:2847-2863.e11. [PMID: 34407390 DOI: 10.1016/j.neuron.2021.07.007] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 05/19/2021] [Accepted: 07/08/2021] [Indexed: 02/06/2023]
Abstract
Asymmetric neuronal expansion is thought to drive evolutionary transitions between lissencephalic and gyrencephalic cerebral cortices. We report that Neurog2 and Ascl1 proneural genes together sustain neurogenic continuity and lissencephaly in rodent cortices. Using transgenic reporter mice and human cerebral organoids, we found that Neurog2 and Ascl1 expression defines a continuum of four lineage-biased neural progenitor cell (NPC) pools. Double+ NPCs, at the hierarchical apex, are least lineage restricted due to Neurog2-Ascl1 cross-repression and display unique features of multipotency (more open chromatin, complex gene regulatory network, G2 pausing). Strikingly, selectively eliminating double+ NPCs by crossing Neurog2-Ascl1 split-Cre mice with diphtheria toxin-dependent "deleter" strains locally disrupts Notch signaling, perturbs neurogenic symmetry, and triggers cortical folding. In support of our discovery that double+ NPCs are Notch-ligand-expressing "niche" cells that control neurogenic periodicity and cortical folding, NEUROG2, ASCL1, and HES1 transcript distribution is modular (adjacent high/low zones) in gyrencephalic macaque cortices, prefiguring future folds.
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Affiliation(s)
- Sisu Han
- Sunnybrook Research Institute, 2075 Bayview Ave, Toronto, ON M4N 3M5, Canada; Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Satoshi Okawa
- Computational Biology Group, Luxembourg Centre for Systems Biomedicine, University of Luxembourg, 4362 Esch-sur-Alzette, Luxembourg; Integrated BioBank of Luxembourg, 3555, 3531 Dudelange, Luxembourg
| | - Grey Atteridge Wilkinson
- Department of Biochemistry and Molecular Biology, ACHRI, HBI, University of Calgary, Calgary, AB T2N 4N1, Canada
| | - Hussein Ghazale
- Sunnybrook Research Institute, 2075 Bayview Ave, Toronto, ON M4N 3M5, Canada; Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Lata Adnani
- Sunnybrook Research Institute, 2075 Bayview Ave, Toronto, ON M4N 3M5, Canada; Department of Biochemistry and Molecular Biology, ACHRI, HBI, University of Calgary, Calgary, AB T2N 4N1, Canada
| | - Rajiv Dixit
- Sunnybrook Research Institute, 2075 Bayview Ave, Toronto, ON M4N 3M5, Canada; Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Ligia Tavares
- i3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135 Porto, Portugal
| | - Imrul Faisal
- Sunnybrook Research Institute, 2075 Bayview Ave, Toronto, ON M4N 3M5, Canada; Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Matthew J Brooks
- Neurobiology-Neurodegeneration & Repair Laboratory, National Eye Institute, National Institutes of Health, Bethesda, MD 20892-1204, USA
| | - Veronique Cortay
- Université Claude Bernard Lyon 1, Inserm, Stem Cell and Brain Research Institute U1208, 69500 Bron, France
| | - Dawn Zinyk
- Sunnybrook Research Institute, 2075 Bayview Ave, Toronto, ON M4N 3M5, Canada
| | - Adam Sivitilli
- Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada; Donnelly Centre, University of Toronto, Toronto, ON M5S 3E1, Canada
| | - Saiqun Li
- Department of Biochemistry and Molecular Biology, ACHRI, HBI, University of Calgary, Calgary, AB T2N 4N1, Canada
| | - Faizan Malik
- Department of Medical Genetics, ACHRI, HBI, University of Calgary, Calgary, AB T2N 4N1, Canada
| | - Yaroslav Ilnytskyy
- Department of Biological Sciences, University of Lethbridge, Lethbridge, AB T1K 3M4, Canada
| | - Vladimir Espinosa Angarica
- Computational Biology Group, Luxembourg Centre for Systems Biomedicine, University of Luxembourg, 4362 Esch-sur-Alzette, Luxembourg
| | - Jinghua Gao
- Sunnybrook Research Institute, 2075 Bayview Ave, Toronto, ON M4N 3M5, Canada; Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Vorapin Chinchalongporn
- Sunnybrook Research Institute, 2075 Bayview Ave, Toronto, ON M4N 3M5, Canada; Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Ana-Maria Oproescu
- Sunnybrook Research Institute, 2075 Bayview Ave, Toronto, ON M4N 3M5, Canada; Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Lakshmy Vasan
- Sunnybrook Research Institute, 2075 Bayview Ave, Toronto, ON M4N 3M5, Canada; Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Yacine Touahri
- Sunnybrook Research Institute, 2075 Bayview Ave, Toronto, ON M4N 3M5, Canada; Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Luke Ajay David
- Sunnybrook Research Institute, 2075 Bayview Ave, Toronto, ON M4N 3M5, Canada; Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Eko Raharjo
- Department of Comparative Biology and Experimental Medicine, HBI, ACHRI, University of Calgary, Calgary, AB T2N 4N1, Canada
| | - Jung-Woong Kim
- Neurobiology-Neurodegeneration & Repair Laboratory, National Eye Institute, National Institutes of Health, Bethesda, MD 20892-1204, USA
| | - Wei Wu
- Department of Pathology and Laboratory Medicine, Charbonneau Cancer Institute, HBI, University of Calgary, Calgary, AB T2N 4Z6, Canada
| | - Waleed Rahmani
- Department of Comparative Biology and Experimental Medicine, HBI, ACHRI, University of Calgary, Calgary, AB T2N 4N1, Canada
| | - Jennifer Ai-Wen Chan
- Department of Pathology and Laboratory Medicine, Charbonneau Cancer Institute, HBI, University of Calgary, Calgary, AB T2N 4Z6, Canada
| | - Igor Kovalchuk
- Department of Biological Sciences, University of Lethbridge, Lethbridge, AB T1K 3M4, Canada
| | - Liliana Attisano
- Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada; Donnelly Centre, University of Toronto, Toronto, ON M5S 3E1, Canada
| | - Deborah Kurrasch
- Department of Medical Genetics, ACHRI, HBI, University of Calgary, Calgary, AB T2N 4N1, Canada
| | - Colette Dehay
- Université Claude Bernard Lyon 1, Inserm, Stem Cell and Brain Research Institute U1208, 69500 Bron, France
| | - Anand Swaroop
- Neurobiology-Neurodegeneration & Repair Laboratory, National Eye Institute, National Institutes of Health, Bethesda, MD 20892-1204, USA
| | - Diogo S Castro
- i3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135 Porto, Portugal
| | - Jeff Biernaskie
- Department of Comparative Biology and Experimental Medicine, HBI, ACHRI, University of Calgary, Calgary, AB T2N 4N1, Canada
| | - Antonio Del Sol
- Computational Biology Group, Luxembourg Centre for Systems Biomedicine, University of Luxembourg, 4362 Esch-sur-Alzette, Luxembourg; CIC bioGUNE, Bizkaia Technology Park, 48160 Derio, Spain; IKERBASQUE, Basque Foundation for Science, Bilbao 48013, Spain
| | - Carol Schuurmans
- Sunnybrook Research Institute, 2075 Bayview Ave, Toronto, ON M4N 3M5, Canada; Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada; Department of Biochemistry and Molecular Biology, ACHRI, HBI, University of Calgary, Calgary, AB T2N 4N1, Canada; Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON M5S 1A8, Canada.
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17
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Glycogen Synthase Kinase 3 Regulates the Genesis of Displaced Retinal Ganglion Cells3. eNeuro 2021; 8:ENEURO.0171-21.2021. [PMID: 34518365 PMCID: PMC8496207 DOI: 10.1523/eneuro.0171-21.2021] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 08/19/2021] [Accepted: 09/02/2021] [Indexed: 01/13/2023] Open
Abstract
Glycogen synthase kinase 3 (GSK3) proteins (GSK3α and GSK3β) are key mediators of signaling pathways, with crucial roles in coordinating fundamental biological processes during neural development. Here we show that the complete loss of GSK3 signaling in mouse retinal progenitors leads to microphthalmia with broad morphologic defects. A single wild-type allele of either Gsk3α or Gsk3β is able to rescue this phenotype. In this genetic context, all cell types are present in a functional retina. However, we unexpectedly detected a large number of cells in the inner nuclear layer expressing retinal ganglion cell (RGC)-specific markers (called displaced RGCs, dRGCs) when at least one allele of Gsk3α is expressed. The excess of dRGCs leads to an increased number of axons projecting into the ipsilateral medial terminal nucleus, an area of the brain belonging to the non-image-forming visual circuit and poorly targeted by RGCs in wild-type retina. Transcriptome analysis and optomotor response assay suggest that at least a subset of dRGCs in Gsk3 mutant mice are direction-selective RGCs. Our study thus uncovers a unique role of GSK3 in controlling the production of ganglion cells in the inner nuclear layer, which correspond to dRGCs, a rare and poorly characterized retinal cell type.
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18
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Mechanisms of Binding Specificity among bHLH Transcription Factors. Int J Mol Sci 2021; 22:ijms22179150. [PMID: 34502060 PMCID: PMC8431614 DOI: 10.3390/ijms22179150] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 08/14/2021] [Accepted: 08/18/2021] [Indexed: 12/25/2022] Open
Abstract
The transcriptome of every cell is orchestrated by the complex network of interaction between transcription factors (TFs) and their binding sites on DNA. Disruption of this network can result in many forms of organism malfunction but also can be the substrate of positive natural selection. However, understanding the specific determinants of each of these individual TF-DNA interactions is a challenging task as it requires integrating the multiple possible mechanisms by which a given TF ends up interacting with a specific genomic region. These mechanisms include DNA motif preferences, which can be determined by nucleotide sequence but also by DNA’s shape; post-translational modifications of the TF, such as phosphorylation; and dimerization partners and co-factors, which can mediate multiple forms of direct or indirect cooperative binding. Binding can also be affected by epigenetic modifications of putative target regions, including DNA methylation and nucleosome occupancy. In this review, we describe how all these mechanisms have a role and crosstalk in one specific family of TFs, the basic helix-loop-helix (bHLH), with a very conserved DNA binding domain and a similar DNA preferred motif, the E-box. Here, we compile and discuss a rich catalog of strategies used by bHLH to acquire TF-specific genome-wide landscapes of binding sites.
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19
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Vasan L, Park E, David LA, Fleming T, Schuurmans C. Direct Neuronal Reprogramming: Bridging the Gap Between Basic Science and Clinical Application. Front Cell Dev Biol 2021; 9:681087. [PMID: 34291049 PMCID: PMC8287587 DOI: 10.3389/fcell.2021.681087] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 06/02/2021] [Indexed: 12/15/2022] Open
Abstract
Direct neuronal reprogramming is an innovative new technology that involves the conversion of somatic cells to induced neurons (iNs) without passing through a pluripotent state. The capacity to make new neurons in the brain, which previously was not achievable, has created great excitement in the field as it has opened the door for the potential treatment of incurable neurodegenerative diseases and brain injuries such as stroke. These neurological disorders are associated with frank neuronal loss, and as new neurons are not made in most of the adult brain, treatment options are limited. Developmental biologists have paved the way for the field of direct neuronal reprogramming by identifying both intrinsic cues, primarily transcription factors (TFs) and miRNAs, and extrinsic cues, including growth factors and other signaling molecules, that induce neurogenesis and specify neuronal subtype identities in the embryonic brain. The striking observation that postmitotic, terminally differentiated somatic cells can be converted to iNs by mis-expression of TFs or miRNAs involved in neural lineage development, and/or by exposure to growth factors or small molecule cocktails that recapitulate the signaling environment of the developing brain, has opened the door to the rapid expansion of new neuronal reprogramming methodologies. Furthermore, the more recent applications of neuronal lineage conversion strategies that target resident glial cells in situ has expanded the clinical potential of direct neuronal reprogramming techniques. Herein, we present an overview of the history, accomplishments, and therapeutic potential of direct neuronal reprogramming as revealed over the last two decades.
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Affiliation(s)
- Lakshmy Vasan
- Sunnybrook Research Institute, Biological Sciences Platform, Toronto, ON, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
| | - Eunjee Park
- Sunnybrook Research Institute, Biological Sciences Platform, Toronto, ON, Canada
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Luke Ajay David
- Sunnybrook Research Institute, Biological Sciences Platform, Toronto, ON, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
| | - Taylor Fleming
- Sunnybrook Research Institute, Biological Sciences Platform, Toronto, ON, Canada
| | - Carol Schuurmans
- Sunnybrook Research Institute, Biological Sciences Platform, Toronto, ON, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada
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20
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Oproescu AM, Han S, Schuurmans C. New Insights Into the Intricacies of Proneural Gene Regulation in the Embryonic and Adult Cerebral Cortex. Front Mol Neurosci 2021; 14:642016. [PMID: 33658912 PMCID: PMC7917194 DOI: 10.3389/fnmol.2021.642016] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Accepted: 01/26/2021] [Indexed: 12/21/2022] Open
Abstract
Historically, the mammalian brain was thought to lack stem cells as no new neurons were found to be made in adulthood. That dogma changed ∼25 years ago with the identification of neural stem cells (NSCs) in the adult rodent forebrain. However, unlike rapidly self-renewing mature tissues (e.g., blood, intestinal crypts, skin), the majority of adult NSCs are quiescent, and those that become 'activated' are restricted to a few neurogenic zones that repopulate specific brain regions. Conversely, embryonic NSCs are actively proliferating and neurogenic. Investigations into the molecular control of the quiescence-to-proliferation-to-differentiation continuum in the embryonic and adult brain have identified proneural genes encoding basic-helix-loop-helix (bHLH) transcription factors (TFs) as critical regulators. These bHLH TFs initiate genetic programs that remove NSCs from quiescence and drive daughter neural progenitor cells (NPCs) to differentiate into specific neural cell subtypes, thereby contributing to the enormous cellular diversity of the adult brain. However, new insights have revealed that proneural gene activities are context-dependent and tightly regulated. Here we review how proneural bHLH TFs are regulated, with a focus on the murine cerebral cortex, drawing parallels where appropriate to other organisms and neural tissues. We discuss upstream regulatory events, post-translational modifications (phosphorylation, ubiquitinylation), protein-protein interactions, epigenetic and metabolic mechanisms that govern bHLH TF expression, stability, localization, and consequent transactivation of downstream target genes. These tight regulatory controls help to explain paradoxical findings of changes to bHLH activity in different cellular contexts.
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Affiliation(s)
- Ana-Maria Oproescu
- Sunnybrook Research Institute, Biological Sciences Platform, Toronto, ON, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
| | - Sisu Han
- Sunnybrook Research Institute, Biological Sciences Platform, Toronto, ON, Canada
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Carol Schuurmans
- Sunnybrook Research Institute, Biological Sciences Platform, Toronto, ON, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada
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21
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Abstract
The mammalian cerebral cortex is the pinnacle of brain evolution, reaching its maximum complexity in terms of neuron number, diversity and functional circuitry. The emergence of this outstanding complexity begins during embryonic development, when a limited number of neural stem and progenitor cells manage to generate myriads of neurons in the appropriate numbers, types and proportions, in a process called neurogenesis. Here we review the current knowledge on the regulation of cortical neurogenesis, beginning with a description of the types of progenitor cells and their lineage relationships. This is followed by a review of the determinants of neuron fate, the molecular and genetic regulatory mechanisms, and considerations on the evolution of cortical neurogenesis in vertebrates leading to humans. We finish with an overview on how dysregulation of neurogenesis is a leading cause of human brain malformations and functional disabilities.
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Affiliation(s)
- Ana Villalba
- Instituto de Neurociencias, Consejo Superior de Investigaciones Científicas & Universidad Miguel Hernández, Sant Joan d'Alacant, Spain
| | - Magdalena Götz
- Institute for Stem Cell Research, Helmholtz Zentrum München & Biomedical Center, Ludwig-Maximilians Universitaet, Planegg-Martinsried, Germany
| | - Víctor Borrell
- Instituto de Neurociencias, Consejo Superior de Investigaciones Científicas & Universidad Miguel Hernández, Sant Joan d'Alacant, Spain.
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22
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Vaid S, Huttner WB. Transcriptional Regulators and Human-Specific/Primate-Specific Genes in Neocortical Neurogenesis. Int J Mol Sci 2020; 21:ijms21134614. [PMID: 32610533 PMCID: PMC7369782 DOI: 10.3390/ijms21134614] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 06/09/2020] [Accepted: 06/26/2020] [Indexed: 12/15/2022] Open
Abstract
During development, starting from a pool of pluripotent stem cells, tissue-specific genetic programs help to shape and develop functional organs. To understand the development of an organ and its disorders, it is important to understand the spatio-temporal dynamics of the gene expression profiles that occur during its development. Modifications in existing genes, the de-novo appearance of new genes, or, occasionally, even the loss of genes, can greatly affect the gene expression profile of any given tissue and contribute to the evolution of organs or of parts of organs. The neocortex is evolutionarily the most recent part of the brain, it is unique to mammals, and is the seat of our higher cognitive abilities. Progenitors that give rise to this tissue undergo sequential waves of differentiation to produce the complete sets of neurons and glial cells that make up a functional neocortex. We will review herein our understanding of the transcriptional regulators that control the neural precursor cells (NPCs) during the generation of the most abundant class of neocortical neurons, the glutametergic neurons. In addition, we will discuss the roles of recently-identified human- and primate-specific genes in promoting neurogenesis, leading to neocortical expansion.
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23
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Marsters CM, Nesan D, Far R, Klenin N, Pittman QJ, Kurrasch DM. Embryonic microglia influence developing hypothalamic glial populations. J Neuroinflammation 2020; 17:146. [PMID: 32375817 PMCID: PMC7201702 DOI: 10.1186/s12974-020-01811-7] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Accepted: 04/13/2020] [Indexed: 11/15/2022] Open
Abstract
Background Although historically microglia were thought to be immature in the fetal brain, evidence of purposeful interactions between these immune cells and nearby neural progenitors is becoming established. Here, we examined the influence of embryonic microglia on gliogenesis within the developing tuberal hypothalamus, a region later important for energy balance, reproduction, and thermoregulation. Methods We used immunohistochemistry to quantify the location and numbers of glial cells in the embryonic brain (E13.5–E17.5), as well as a pharmacological approach (i.e., PLX5622) to knock down fetal microglia. We also conducted cytokine and chemokine analyses on embryonic brains in the presence or absence of microglia, and a neurosphere assay to test the effects of the altered cytokines on hypothalamic progenitor behaviors. Results We identified a subpopulation of activated microglia that congregated adjacent to the third ventricle alongside embryonic Olig2+ neural progenitor cells (NPCs) that are destined to give rise to oligodendrocyte and astrocyte populations. In the absence of microglia, we observed an increase in Olig2+ glial progenitor cells that remained at the ventricle by E17.5 and a concomitant decrease of these Olig2+ cells in the mantle zone, indicative of a delay in migration of these precursor cells. A further examination of maturing oligodendrocytes in the hypothalamic grey and white matter area in the absence of microglia revealed migrating oligodendrocyte progenitor cells (OPCs) within the grey matter at E17.5, a time point when OPCs begin to slow their migration. Finally, quantification of cytokine and chemokine signaling in ex vivo E15.5 hypothalamic cultures +/− microglia revealed decreases in the protein levels of several cytokines in the absence of microglia. We assayed the influence of two downregulated cytokines (CCL2 and CXCL10) on neurosphere-forming capacity and lineage commitment of hypothalamic NPCs in culture and showed an increase in NPC proliferation as well as neuronal and oligodendrocyte differentiation. Conclusion These data demonstrate that microglia influence gliogenesis in the developing tuberal hypothalamus.
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Affiliation(s)
- Candace M Marsters
- Department of Medical Genetics, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Department of Physiology & Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
| | - Dinushan Nesan
- Department of Medical Genetics, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
| | - Rena Far
- Department of Medical Genetics, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
| | - Natalia Klenin
- Department of Medical Genetics, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
| | - Quentin J Pittman
- Department of Physiology & Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
| | - Deborah M Kurrasch
- Department of Medical Genetics, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada. .,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada. .,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada.
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24
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Kim Y, Jeong J, Choi D. Small-molecule-mediated reprogramming: a silver lining for regenerative medicine. Exp Mol Med 2020; 52:213-226. [PMID: 32080339 PMCID: PMC7062739 DOI: 10.1038/s12276-020-0383-3] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Revised: 12/01/2019] [Accepted: 12/27/2019] [Indexed: 12/25/2022] Open
Abstract
Techniques for reprogramming somatic cells create new opportunities for drug screening, disease modeling, artificial organ development, and cell therapy. The development of reprogramming techniques has grown exponentially since the discovery of induced pluripotent stem cells (iPSCs) by the transduction of four factors (OCT3/4, SOX2, c-MYC, and KLF4) in mouse embryonic fibroblasts. Initial studies on iPSCs led to direct-conversion techniques using transcription factors expressed mainly in target cells. However, reprogramming transcription factors with a virus risks integrating viral DNA and can be complicated by oncogenes. To address these problems, many researchers are developing reprogramming methods that use clinically applicable small molecules and growth factors. This review summarizes research trends in reprogramming cells using small molecules and growth factors, including their modes of action. The reprogramming of cells using small molecules to generate viable, safe stem-cell populations could transform stem-cell therapies, disease modeling and artificial organ development. Existing ways of reprogramming cells to generate stem cells carry risks, because the methods used often involve using viral DNA components or oncogenes, genes with the potential to turn cells into tumour cells. Safer, inexpensive alternatives are sought by scientists, and the efficient reprogramming of cells using small molecules and growth factors shows promise. Dongho Choi and co-workers at Hanyang University College of Medicine in Seoul, South Korea, reviewed recent research highlighting how small molecules including chemical compounds, plant derivatives and certain approved drugs are being used effectively to create different stem-cell populations. Recent successes are also contributing valuable insights into how stem cells differentiate into different cell types.
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Affiliation(s)
- Yohan Kim
- Department of Surgery, Hanyang University College of Medicine, Seoul, 04763, Korea.,HY Indang Center of Regenerative Medicine and Stem Cell Research, Hanyang University, Seoul, 04763, Korea
| | - Jaemin Jeong
- Department of Surgery, Hanyang University College of Medicine, Seoul, 04763, Korea.,HY Indang Center of Regenerative Medicine and Stem Cell Research, Hanyang University, Seoul, 04763, Korea
| | - Dongho Choi
- Department of Surgery, Hanyang University College of Medicine, Seoul, 04763, Korea. .,HY Indang Center of Regenerative Medicine and Stem Cell Research, Hanyang University, Seoul, 04763, Korea.
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25
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López-Tobón A, Villa CE, Cheroni C, Trattaro S, Caporale N, Conforti P, Iennaco R, Lachgar M, Rigoli MT, Marcó de la Cruz B, Lo Riso P, Tenderini E, Troglio F, De Simone M, Liste-Noya I, Macino G, Pagani M, Cattaneo E, Testa G. Human Cortical Organoids Expose a Differential Function of GSK3 on Cortical Neurogenesis. Stem Cell Reports 2019; 13:847-861. [PMID: 31607568 PMCID: PMC6893153 DOI: 10.1016/j.stemcr.2019.09.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Revised: 09/12/2019] [Accepted: 09/13/2019] [Indexed: 01/08/2023] Open
Abstract
The regulation of the proliferation and polarity of neural progenitors is crucial for the development of the brain cortex. Animal studies have implicated glycogen synthase kinase 3 (GSK3) as a pivotal regulator of both proliferation and polarity, yet the functional relevance of its signaling for the unique features of human corticogenesis remains to be elucidated. We harnessed human cortical brain organoids to probe the longitudinal impact of GSK3 inhibition through multiple developmental stages. Chronic GSK3 inhibition increased the proliferation of neural progenitors and caused massive derangement of cortical tissue architecture. Single-cell transcriptome profiling revealed a direct impact on early neurogenesis and uncovered a selective role of GSK3 in the regulation of glutamatergic lineages and outer radial glia output. Our dissection of the GSK3-dependent transcriptional network in human corticogenesis underscores the robustness of the programs determining neuronal identity independent of tissue architecture. Cortical organoids recapitulate stereotypical neurogenic trajectories GSK3 inhibition disrupts neuroepithelium polarity and cortical tissue organization GSK3 activity controls oRG production and neurogenesis
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Affiliation(s)
- Alejandro López-Tobón
- Laboratory of Stem Cell Epigenetics, IEO, European Institute of Oncology, IRCCS, Milan, Italy; Department of Oncology and Hemato-oncology, University of Milan, Milan, Italy
| | - Carlo Emanuele Villa
- Laboratory of Stem Cell Epigenetics, IEO, European Institute of Oncology, IRCCS, Milan, Italy
| | - Cristina Cheroni
- Laboratory of Stem Cell Epigenetics, IEO, European Institute of Oncology, IRCCS, Milan, Italy; Department of Oncology and Hemato-oncology, University of Milan, Milan, Italy
| | - Sebastiano Trattaro
- Laboratory of Stem Cell Epigenetics, IEO, European Institute of Oncology, IRCCS, Milan, Italy; Department of Oncology and Hemato-oncology, University of Milan, Milan, Italy
| | - Nicolò Caporale
- Laboratory of Stem Cell Epigenetics, IEO, European Institute of Oncology, IRCCS, Milan, Italy; Department of Oncology and Hemato-oncology, University of Milan, Milan, Italy
| | - Paola Conforti
- Department of Biosciences, University of Milan, Milan 20133, Italy; Istituto Nazionale di Genetica Molecolare "Romeo ed Enrica Invernizzi", Milan 20122, Italy
| | - Raffaele Iennaco
- Department of Biosciences, University of Milan, Milan 20133, Italy; Istituto Nazionale di Genetica Molecolare "Romeo ed Enrica Invernizzi", Milan 20122, Italy
| | - Maria Lachgar
- Unidad de Regeneración Neural, Unidad Funcional de Investigación de Enfermedades Crónicas, Instituto de Salud Carlos III (ISCIII), Madrid, Spain
| | - Marco Tullio Rigoli
- Laboratory of Stem Cell Epigenetics, IEO, European Institute of Oncology, IRCCS, Milan, Italy
| | - Berta Marcó de la Cruz
- Laboratory of Stem Cell Epigenetics, IEO, European Institute of Oncology, IRCCS, Milan, Italy
| | - Pietro Lo Riso
- Laboratory of Stem Cell Epigenetics, IEO, European Institute of Oncology, IRCCS, Milan, Italy
| | - Erika Tenderini
- Laboratory of Stem Cell Epigenetics, IEO, European Institute of Oncology, IRCCS, Milan, Italy
| | - Flavia Troglio
- Laboratory of Stem Cell Epigenetics, IEO, European Institute of Oncology, IRCCS, Milan, Italy
| | - Marco De Simone
- Istituto Nazionale di Genetica Molecolare "Romeo ed Enrica Invernizzi", Milan 20122, Italy; Department of Medical Biotechnology and Translational Medicine, University of Milan, Milan, Italy
| | - Isabel Liste-Noya
- Unidad de Regeneración Neural, Unidad Funcional de Investigación de Enfermedades Crónicas, Instituto de Salud Carlos III (ISCIII), Madrid, Spain
| | - Giuseppe Macino
- Department of Molecular Medicine, Sapienza Università di Roma, Rome, Italy
| | - Massimiliano Pagani
- Istituto Nazionale di Genetica Molecolare "Romeo ed Enrica Invernizzi", Milan 20122, Italy; Department of Medical Biotechnology and Translational Medicine, University of Milan, Milan, Italy
| | - Elena Cattaneo
- Department of Biosciences, University of Milan, Milan 20133, Italy; Istituto Nazionale di Genetica Molecolare "Romeo ed Enrica Invernizzi", Milan 20122, Italy
| | - Giuseppe Testa
- Laboratory of Stem Cell Epigenetics, IEO, European Institute of Oncology, IRCCS, Milan, Italy; Department of Oncology and Hemato-oncology, University of Milan, Milan, Italy.
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26
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Donega V, Marcy G, Lo Giudice Q, Zweifel S, Angonin D, Fiorelli R, Abrous DN, Rival-Gervier S, Koehl M, Jabaudon D, Raineteau O. Transcriptional Dysregulation in Postnatal Glutamatergic Progenitors Contributes to Closure of the Cortical Neurogenic Period. Cell Rep 2019. [PMID: 29514086 DOI: 10.1016/j.celrep.2018.02.030] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Progenitors of cortical glutamatergic neurons (Glu progenitors) are usually thought to switch fate before birth to produce astrocytes. We used fate-mapping approaches to show that a large fraction of Glu progenitors persist in the postnatal forebrain after closure of the cortical neurogenesis period. Postnatal Glu progenitors do not accumulate during embryonal development but are produced by embryonal radial glial cells that persist after birth in the dorsal subventricular zone and continue to give rise to cortical neurons, although with low efficiency. Single-cell RNA sequencing reveals a dysregulation of transcriptional programs, which parallels changes in m6A methylation and correlates with the gradual decline in cortical neurogenesis observed in vivo. Rescuing experiments show that postnatal progenitors are partially permissive to genetic and pharmacological manipulations. Our study provides an in-depth characterization of postnatal Glu progenitors and identifies potential therapeutic targets for promoting brain repair.
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Affiliation(s)
- Vanessa Donega
- Univ Lyon, Université Claude Bernard Lyon 1, Inserm, Stem Cell and Brain Research Institute U1208, 69500 Bron, France.
| | - Guillaume Marcy
- Univ Lyon, Université Claude Bernard Lyon 1, Inserm, Stem Cell and Brain Research Institute U1208, 69500 Bron, France; Neurogenetics Department, Ecole Pratique des Hautes Etudes, PSL Research University, 75014 Paris, France
| | - Quentin Lo Giudice
- Univ Lyon, Université Claude Bernard Lyon 1, Inserm, Stem Cell and Brain Research Institute U1208, 69500 Bron, France
| | - Stefan Zweifel
- Univ Lyon, Université Claude Bernard Lyon 1, Inserm, Stem Cell and Brain Research Institute U1208, 69500 Bron, France
| | - Diane Angonin
- Univ Lyon, Université Claude Bernard Lyon 1, Inserm, Stem Cell and Brain Research Institute U1208, 69500 Bron, France
| | - Roberto Fiorelli
- Brain Research Institute, University of Zürich/ETHZ, Zürich, Switzerland
| | - Djoher Nora Abrous
- Neurocentre Magendie, Neurogenesis and Physiopathology Group, Inserm, U1215, 33077 Bordeaux, France; Université de Bordeaux, 33077 Bordeaux, France
| | - Sylvie Rival-Gervier
- Stem Cell and Brain Research Institute U1208, Université Claude Bernard Lyon 1, Inserm, INRA, USC1361, 69500 Bron, France
| | - Muriel Koehl
- Neurocentre Magendie, Neurogenesis and Physiopathology Group, Inserm, U1215, 33077 Bordeaux, France; Université de Bordeaux, 33077 Bordeaux, France
| | - Denis Jabaudon
- Department of Basic Neurosciences, University of Geneva, Geneva, Switzerland
| | - Olivier Raineteau
- Univ Lyon, Université Claude Bernard Lyon 1, Inserm, Stem Cell and Brain Research Institute U1208, 69500 Bron, France; Brain Research Institute, University of Zürich/ETHZ, Zürich, Switzerland.
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27
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Ma NX, Yin JC, Chen G. Transcriptome Analysis of Small Molecule-Mediated Astrocyte-to-Neuron Reprogramming. Front Cell Dev Biol 2019; 7:82. [PMID: 31231645 PMCID: PMC6558402 DOI: 10.3389/fcell.2019.00082] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Accepted: 05/01/2019] [Indexed: 12/21/2022] Open
Abstract
Chemical reprogramming of astrocytes into neurons represents a promising approach to regenerate new neurons for brain repair, but the underlying mechanisms driving this trans-differentiation process are not well understood. We have recently identified four small molecules – CHIR99021, DAPT, LDN193189, and SB431542 – that can efficiently reprogram cultured human fetal astrocytes into functional neurons. Here we employ the next generation of RNA-sequencing technology to investigate the transcriptome changes during the astrocyte-to-neuron (AtN) conversion process. We found that the four small molecules can rapidly activate the hedgehog signaling pathway while downregulating many glial genes such as FN1 and MYL9 within 24 h of treatment. Chemical reprogramming is mediated by several waves of differential gene expression, including upregulation of hedgehog, Wnt/β-catenin, and Notch signaling pathways, together with downregulation of TGF-β and JAK/STAT signaling pathways. Our gene network analyses reveal many well-connected hub genes such as repulsive guidance molecule A (RGMA), neuronatin (NNAT), neurogenin 2 (NEUROG2), NPTX2, MOXD1, JAG1, and GAP43, which may coordinate the chemical reprogramming process. Together, these findings provide critical insights into the molecular cascades triggered by a combination of small molecules that eventually leads to chemical conversion of astrocytes into neurons.
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Affiliation(s)
- Ning-Xin Ma
- Department of Biology, Huck Institutes of Life Sciences, Pennsylvania State University, University Park, PA, United States
| | - Jiu-Chao Yin
- Department of Biology, Huck Institutes of Life Sciences, Pennsylvania State University, University Park, PA, United States
| | - Gong Chen
- Department of Biology, Huck Institutes of Life Sciences, Pennsylvania State University, University Park, PA, United States
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28
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Aydin B, Kakumanu A, Rossillo M, Moreno-Estellés M, Garipler G, Ringstad N, Flames N, Mahony S, Mazzoni EO. Proneural factors Ascl1 and Neurog2 contribute to neuronal subtype identities by establishing distinct chromatin landscapes. Nat Neurosci 2019; 22:897-908. [PMID: 31086315 PMCID: PMC6556771 DOI: 10.1038/s41593-019-0399-y] [Citation(s) in RCA: 74] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Accepted: 03/28/2019] [Indexed: 11/29/2022]
Abstract
Developmental programs that generate the astonishing neuronal diversity of the nervous system are not completely understood and thus present a significant challenge for clinical applications of guided cell differentiation strategies. Using direct neuronal programming of embryonic stem cells, we found that two main vertebrate proneural factors, Ascl1 and Neurog2, induce different neuronal fates by binding to largely different sets of genomic sites. Their divergent binding patterns are not determined by the previous chromatin state but are distinguished by enrichment of specific E-box sequences which reflect the binding preferences of the DNA-binding domains. The divergent Ascl1 and Neurog2 binding patterns result in distinct chromatin accessibility and enhancer activity profiles that differentially shape the binding of downstream transcription factors during neuronal differentiation. This study provides a mechanistic understanding of how transcription factors constrain terminal cell fates, and it delineates the importance of choosing the right proneural factor in neuronal reprogramming strategies.
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Affiliation(s)
- Begüm Aydin
- Department of Biology, New York University, New York, NY, USA.,Neuroscience Institute, Department of Neuroscience and Physiology, NYU School of Medicine, New York, NY, USA
| | - Akshay Kakumanu
- Center for Eukaryotic Gene Regulation, Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, USA
| | - Mary Rossillo
- Skirball Institute of Biomolecular Medicine, NYU School of Medicine, New York, NY, USA
| | - Mireia Moreno-Estellés
- Developmental Neurobiology Unit, Instituto de Biomedicina de Valencia IBV-CSIC, Valencia, Spain
| | - Görkem Garipler
- Department of Biology, New York University, New York, NY, USA.,Neuroscience Institute, Department of Neuroscience and Physiology, NYU School of Medicine, New York, NY, USA
| | - Niels Ringstad
- Skirball Institute of Biomolecular Medicine, NYU School of Medicine, New York, NY, USA
| | - Nuria Flames
- Developmental Neurobiology Unit, Instituto de Biomedicina de Valencia IBV-CSIC, Valencia, Spain
| | - Shaun Mahony
- Center for Eukaryotic Gene Regulation, Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, USA.
| | - Esteban O Mazzoni
- Department of Biology, New York University, New York, NY, USA. .,Neuroscience Institute, Department of Neuroscience and Physiology, NYU School of Medicine, New York, NY, USA.
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29
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Ashton NJ, Nevado-Holgado AJ, Barber IS, Lynham S, Gupta V, Chatterjee P, Goozee K, Hone E, Pedrini S, Blennow K, Schöll M, Zetterberg H, Ellis KA, Bush AI, Rowe CC, Villemagne VL, Ames D, Masters CL, Aarsland D, Powell J, Lovestone S, Martins R, Hye A. A plasma protein classifier for predicting amyloid burden for preclinical Alzheimer's disease. SCIENCE ADVANCES 2019; 5:eaau7220. [PMID: 30775436 PMCID: PMC6365111 DOI: 10.1126/sciadv.aau7220] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Accepted: 12/19/2018] [Indexed: 05/03/2023]
Abstract
A blood-based assessment of preclinical disease would have huge potential in the enrichment of participants for Alzheimer's disease (AD) therapeutic trials. In this study, cognitively unimpaired individuals from the AIBL and KARVIAH cohorts were defined as Aβ negative or Aβ positive by positron emission tomography. Nontargeted proteomic analysis that incorporated peptide fractionation and high-resolution mass spectrometry quantified relative protein abundances in plasma samples from all participants. A protein classifier model was trained to predict Aβ-positive participants using feature selection and machine learning in AIBL and independently assessed in KARVIAH. A 12-feature model for predicting Aβ-positive participants was established and demonstrated high accuracy (testing area under the receiver operator characteristic curve = 0.891, sensitivity = 0.78, and specificity = 0.77). This extensive plasma proteomic study has unbiasedly highlighted putative and novel candidates for AD pathology that should be further validated with automated methodologies.
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Affiliation(s)
- Nicholas J. Ashton
- King’s College London, Institute of Psychiatry, Psychology and Neuroscience, Maurice Wohl Institute Clinical Neuroscience Institute, London, UK
- NIHR Biomedical Research Centre for Mental Health and Biomedical Research Unit for Dementia at South London and Maudsley NHS Foundation, London, UK
- Department of Psychiatry and Neurochemistry, Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden
- Wallenberg Centre for Molecular and Translational Medicine, University of Gothenburg, Gothenburg, Sweden
| | | | | | - Steven Lynham
- Proteomics Core Facility, James Black Centre, King’s College, London, UK
| | - Veer Gupta
- School of Medical Sciences, Edith Cowan University, Joondalup, WA, Australia
- Cooperative Research Centre for Mental Health, Carlton South, VIC, Australia
- School of Medicine, Faculty of Health, Deakin University, 3220 VIC, Australia
| | - Pratishtha Chatterjee
- School of Medical Sciences, Edith Cowan University, Joondalup, WA, Australia
- KaRa Institute of Neurological Diseases, Macquarie Park, NSW, Australia
- Department of Biomedical Sciences, Macquarie University, 2109, NSW, Australia
| | - Kathryn Goozee
- KaRa Institute of Neurological Diseases, Macquarie Park, NSW, Australia
- Department of Biomedical Sciences, Macquarie University, 2109, NSW, Australia
- Clinical Research Department, Anglicare, Sydney, NSW, Australia
- School of Psychiatry and Clinical Neurosciences, University of Western Australia, WA, Australia
| | - Eugene Hone
- School of Medical Sciences, Edith Cowan University, Joondalup, WA, Australia
- Cooperative Research Centre for Mental Health, Carlton South, VIC, Australia
| | - Steve Pedrini
- School of Medical Sciences, Edith Cowan University, Joondalup, WA, Australia
- Cooperative Research Centre for Mental Health, Carlton South, VIC, Australia
| | - Kaj Blennow
- Department of Psychiatry and Neurochemistry, Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
| | - Michael Schöll
- Department of Psychiatry and Neurochemistry, Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden
- Wallenberg Centre for Molecular and Translational Medicine, University of Gothenburg, Gothenburg, Sweden
| | - Henrik Zetterberg
- Department of Psychiatry and Neurochemistry, Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
- Department of Molecular Neuroscience, UCL Institute of Neurology, Queen Square, London, UK
- UK Dementia Research Institute at UCL, London, UK
| | - Kathryn A. Ellis
- Academic Unit for Psychiatry of Old Age, St. George’s Hospital, University of Melbourne, VIC, Australia
| | - Ashley I. Bush
- Cooperative Research Centre for Mental Health, Carlton South, VIC, Australia
- The Florey Institute, University of Melbourne, VIC, Australia
| | - Christopher C. Rowe
- Department of Molecular Imaging and Therapy, Austin Health, Heidelberg, VIC, Australia
| | - Victor L. Villemagne
- Department of Molecular Imaging and Therapy, Austin Health, Heidelberg, VIC, Australia
| | - David Ames
- Academic Unit for Psychiatry of Old Age, St. George’s Hospital, University of Melbourne, VIC, Australia
- National Ageing Research Institute, Parkville, VIC, Australia
| | | | - Dag Aarsland
- King’s College London, Institute of Psychiatry, Psychology and Neuroscience, Maurice Wohl Institute Clinical Neuroscience Institute, London, UK
- NIHR Biomedical Research Centre for Mental Health and Biomedical Research Unit for Dementia at South London and Maudsley NHS Foundation, London, UK
- Centre for Age-Related Medicine, Stavanger University Hospital, Stavanger, Norway
| | - John Powell
- King’s College London, Institute of Psychiatry, Psychology and Neuroscience, Maurice Wohl Institute Clinical Neuroscience Institute, London, UK
- NIHR Biomedical Research Centre for Mental Health and Biomedical Research Unit for Dementia at South London and Maudsley NHS Foundation, London, UK
| | | | - Ralph Martins
- School of Medical Sciences, Edith Cowan University, Joondalup, WA, Australia
- Cooperative Research Centre for Mental Health, Carlton South, VIC, Australia
- KaRa Institute of Neurological Diseases, Macquarie Park, NSW, Australia
- Department of Biomedical Sciences, Macquarie University, 2109, NSW, Australia
| | - Abdul Hye
- King’s College London, Institute of Psychiatry, Psychology and Neuroscience, Maurice Wohl Institute Clinical Neuroscience Institute, London, UK
- NIHR Biomedical Research Centre for Mental Health and Biomedical Research Unit for Dementia at South London and Maudsley NHS Foundation, London, UK
- Corresponding author.
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Robinson M, Fraser I, McKee E, Scheck K, Chang L, Willerth SM. Transdifferentiating Astrocytes Into Neurons Using ASCL1 Functionalized With a Novel Intracellular Protein Delivery Technology. Front Bioeng Biotechnol 2018; 6:173. [PMID: 30525033 PMCID: PMC6258721 DOI: 10.3389/fbioe.2018.00173] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Accepted: 10/31/2018] [Indexed: 01/26/2023] Open
Abstract
Cellular transdifferentiation changes mature cells from one phenotype into another by altering their gene expression patterns. Manipulating expression of transcription factors, proteins that bind to DNA promoter regions, regulates the levels of key developmental genes. Viral delivery of transcription factors can efficiently reprogram somatic cells, but this method possesses undesirable side effects, including mutations leading to oncogenesis. Using protein transduction domains (PTDs) fused to transcription factors to deliver exogenous transcription factors serves as an alternative strategy that avoids the issues associated with DNA integration into the host genome. However, lysosomal degradation and inefficient nuclear localization pose significant barriers when performing PTD-mediated reprogramming. Here, we investigate a novel PTD by placing a secretion signal sequence next to a cleavage inhibition sequence at the end of the target transcription factor–achaete scute homolog 1 (ASCL1), a powerful regulator of neurogenesis, resulting in superior stability and nuclear localization. A fusion protein consisting of the amino acid sequence of ASCL1 transcription factor with this novel PTD added can transdifferentiate cerebral cortex astrocytes into neurons. Additionally, we show that the synergistic action of certain small molecules improves the efficiency of the transdifferentiation process. This study serves as the first step toward developing a clinically relevant in vivo transdifferentiation strategy for converting astrocytes into neurons.
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Affiliation(s)
- Meghan Robinson
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
| | - Ian Fraser
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada.,Biomedical Engineering Program, University of Victoria, Victoria, BC, Canada
| | - Emily McKee
- Biomedical Engineering Program, University of Victoria, Victoria, BC, Canada
| | - Kali Scheck
- Biology Program, University of Victoria, Victoria, BC, Canada
| | - Lillian Chang
- Biochemistry Program, Bates College, Lewiston, ME, United States
| | - Stephanie M Willerth
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada.,Biomedical Engineering Program, University of Victoria, Victoria, BC, Canada.,Mechanical Engineering, Faculty of Engineering, University of Victoria, Victoria, BC, Canada.,Center for Biomedical Research, Faculty of Engineering, University of Victoria, Victoria, BC, Canada.,International Collaboration for Repair Discovery, University of British Columbia, Vancouver, BC, Canada
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31
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Han S, Dennis DJ, Balakrishnan A, Dixit R, Britz O, Zinyk D, Touahri Y, Olender T, Brand M, Guillemot F, Kurrasch D, Schuurmans C. A non-canonical role for the proneural gene Neurog1 as a negative regulator of neocortical neurogenesis. Development 2018; 145:dev157719. [PMID: 30201687 PMCID: PMC6198467 DOI: 10.1242/dev.157719] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Accepted: 08/31/2018] [Indexed: 02/05/2023]
Abstract
Neural progenitors undergo temporal identity transitions to sequentially generate the neuronal and glial cells that make up the mature brain. Proneural genes have well-characterised roles in promoting neural cell differentiation and subtype specification, but they also regulate the timing of identity transitions through poorly understood mechanisms. Here, we investigated how the highly related proneural genes Neurog1 and Neurog2 interact to control the timing of neocortical neurogenesis. We found that Neurog1 acts in an atypical fashion as it is required to suppress rather than promote neuronal differentiation in early corticogenesis. In Neurog1-/- neocortices, early born neurons differentiate in excess, whereas, in vitro, Neurog1-/- progenitors have a decreased propensity to proliferate and form neurospheres. Instead, Neurog1-/- progenitors preferentially generate neurons, a phenotype restricted to the Neurog2+ progenitor pool. Mechanistically, Neurog1 and Neurog2 heterodimerise, and while Neurog1 and Neurog2 individually promote neurogenesis, misexpression together blocks this effect. Finally, Neurog1 is also required to induce the expression of neurogenic factors (Dll1 and Hes5) and to repress the expression of neuronal differentiation genes (Fezf2 and Neurod6). Neurog1 thus employs different mechanisms to temper the pace of early neocortical neurogenesis.
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Affiliation(s)
- Sisu Han
- Biological Sciences Platform, Sunnybrook Research Institute, Toronto, ON M4N 3M5, Canada
- Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Daniel J Dennis
- Biological Sciences Platform, Sunnybrook Research Institute, Toronto, ON M4N 3M5, Canada
- Department of Biochemistry and Molecular Biology, Alberta Children's Hospital Research Institute, Hotchkiss Brain Institute, University of Calgary, Calgary, AB T2N 4N1, Canada
- Department of Molecular Genetics, Alberta Children's Hospital Research Institute, University of Calgary, Calgary, AB T2N 4N1, Canada
| | - Anjali Balakrishnan
- Biological Sciences Platform, Sunnybrook Research Institute, Toronto, ON M4N 3M5, Canada
- Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Rajiv Dixit
- Biological Sciences Platform, Sunnybrook Research Institute, Toronto, ON M4N 3M5, Canada
| | - Olivier Britz
- The Francis Crick Institute-Mill Hill Laboratory, London NW7 1AA, UK
| | - Dawn Zinyk
- Biological Sciences Platform, Sunnybrook Research Institute, Toronto, ON M4N 3M5, Canada
| | - Yacine Touahri
- Biological Sciences Platform, Sunnybrook Research Institute, Toronto, ON M4N 3M5, Canada
| | - Thomas Olender
- Ottawa Hospital Research Institute, Ottawa, ON K1H 8L6, Canada
| | - Marjorie Brand
- Ottawa Hospital Research Institute, Ottawa, ON K1H 8L6, Canada
| | | | - Deborah Kurrasch
- Department of Molecular Genetics, Alberta Children's Hospital Research Institute, University of Calgary, Calgary, AB T2N 4N1, Canada
| | - Carol Schuurmans
- Biological Sciences Platform, Sunnybrook Research Institute, Toronto, ON M4N 3M5, Canada
- Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada
- Department of Biochemistry and Molecular Biology, Alberta Children's Hospital Research Institute, Hotchkiss Brain Institute, University of Calgary, Calgary, AB T2N 4N1, Canada
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Le Dréau G, Escalona R, Fueyo R, Herrera A, Martínez JD, Usieto S, Menendez A, Pons S, Martinez-Balbas MA, Marti E. E proteins sharpen neurogenesis by modulating proneural bHLH transcription factors' activity in an E-box-dependent manner. eLife 2018; 7:37267. [PMID: 30095408 PMCID: PMC6126921 DOI: 10.7554/elife.37267] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Accepted: 08/09/2018] [Indexed: 12/18/2022] Open
Abstract
Class II HLH proteins heterodimerize with class I HLH/E proteins to regulate transcription. Here, we show that E proteins sharpen neurogenesis by adjusting the neurogenic strength of the distinct proneural proteins. We find that inhibiting BMP signaling or its target ID2 in the chick embryo spinal cord, impairs the neuronal production from progenitors expressing ATOH1/ASCL1, but less severely that from progenitors expressing NEUROG1/2/PTF1a. We show this context-dependent response to result from the differential modulation of proneural proteins’ activity by E proteins. E proteins synergize with proneural proteins when acting on CAGSTG motifs, thereby facilitating the activity of ASCL1/ATOH1 which preferentially bind to such motifs. Conversely, E proteins restrict the neurogenic strength of NEUROG1/2 by directly inhibiting their preferential binding to CADATG motifs. Since we find this mechanism to be conserved in corticogenesis, we propose this differential co-operation of E proteins with proneural proteins as a novel though general feature of their mechanism of action. The brain and spinal cord are made up of a range of cell types that carry out different roles within the central nervous system. Each type of neuron is uniquely specialized to do its job. Neurons are produced early during development, when they differentiate from a group of cells called neural progenitor cells. Within these groups, molecules called proneural proteins control which types of neurons will develop from the neural progenitor cells, and how many of them. Proneural proteins work by binding to specific patterns in the DNA, called E-boxes, with the help of E proteins. E proteins are typically understood to be passive partners, working with each different proneural protein indiscriminately. However, Le Dréau, Escalona et al. discovered that E proteins in fact have a much more active role to play. Using chick embryos, it was found that E proteins influence the way different proneural proteins bind to DNA. The E proteins have preferences for certain E-boxes in the DNA, just like proneural proteins do. The E proteins enhanced the activity of the proneural proteins that share their E-box preference, and reined in the activity of proneural proteins that prefer other E-boxes. As a result, the E proteins controlled the ability of these proteins to instruct neural progenitor cells to produce specific, specialized neurons, and thus ensured that the distinct types of neurons were produced in appropriate amounts. These findings will help shed light on the roles E proteins play in the development of the central nervous system, and the processes that control growth and lead to cell diversity. The results may also have applications in the field of regenerative medicine, as proneural proteins play an important role in cell reprogramming.
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Affiliation(s)
- Gwenvael Le Dréau
- Department of Developmental Biology, Instituto de Biología Molecular de Barcelona, Barcelona, Spain
| | - René Escalona
- Department of Developmental Biology, Instituto de Biología Molecular de Barcelona, Barcelona, Spain
| | - Raquel Fueyo
- Department of Molecular Genomics, Instituto de Biología Molecular de Barcelona, Barcelona, Spain
| | - Antonio Herrera
- Department of Developmental Biology, Instituto de Biología Molecular de Barcelona, Barcelona, Spain
| | - Juan D Martínez
- Department of Developmental Biology, Instituto de Biología Molecular de Barcelona, Barcelona, Spain
| | - Susana Usieto
- Department of Developmental Biology, Instituto de Biología Molecular de Barcelona, Barcelona, Spain
| | - Anghara Menendez
- Department of Cell Biology, Instituto de Biología Molecular de Barcelona, Barcelona, Spain
| | - Sebastian Pons
- Department of Cell Biology, Instituto de Biología Molecular de Barcelona, Barcelona, Spain
| | - Marian A Martinez-Balbas
- Department of Molecular Genomics, Instituto de Biología Molecular de Barcelona, Barcelona, Spain
| | - Elisa Marti
- Department of Developmental Biology, Instituto de Biología Molecular de Barcelona, Barcelona, Spain
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Bonnet F, Molina A, Roussat M, Azais M, Bel-Vialar S, Gautrais J, Pituello F, Agius E. Neurogenic decisions require a cell cycle independent function of the CDC25B phosphatase. eLife 2018; 7:32937. [PMID: 29969095 PMCID: PMC6051746 DOI: 10.7554/elife.32937] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Accepted: 06/08/2018] [Indexed: 01/06/2023] Open
Abstract
A fundamental issue in developmental biology and in organ homeostasis is understanding the molecular mechanisms governing the balance between stem cell maintenance and differentiation into a specific lineage. Accumulating data suggest that cell cycle dynamics play a major role in the regulation of this balance. Here we show that the G2/M cell cycle regulator CDC25B phosphatase is required in mammals to finely tune neuronal production in the neural tube. We show that in chick neural progenitors, CDC25B activity favors fast nuclei departure from the apical surface in early G1, stimulates neurogenic divisions and promotes neuronal differentiation. We design a mathematical model showing that within a limited period of time, cell cycle length modifications cannot account for changes in the ratio of the mode of division. Using a CDC25B point mutation that cannot interact with CDK, we show that part of CDC25B activity is independent of its action on the cell cycle.
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Affiliation(s)
- Frédéric Bonnet
- Centre de Biologie du Développement, Centre de Biologie Intégrative, Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Angie Molina
- Centre de Biologie du Développement, Centre de Biologie Intégrative, Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Mélanie Roussat
- Centre de Biologie du Développement, Centre de Biologie Intégrative, Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Manon Azais
- Centre de Recherches sur la Cognition Animale, Centre de Biologie Intégrative., Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Sophie Bel-Vialar
- Centre de Biologie du Développement, Centre de Biologie Intégrative, Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Jacques Gautrais
- Centre de Recherches sur la Cognition Animale, Centre de Biologie Intégrative., Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Fabienne Pituello
- Centre de Biologie du Développement, Centre de Biologie Intégrative, Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Eric Agius
- Centre de Biologie du Développement, Centre de Biologie Intégrative, Université de Toulouse, CNRS, UPS, Toulouse, France
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Dennis DJ, Han S, Schuurmans C. bHLH transcription factors in neural development, disease, and reprogramming. Brain Res 2018; 1705:48-65. [PMID: 29544733 DOI: 10.1016/j.brainres.2018.03.013] [Citation(s) in RCA: 120] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Revised: 03/07/2018] [Accepted: 03/10/2018] [Indexed: 01/16/2023]
Abstract
The formation of functional neural circuits in the vertebrate central nervous system (CNS) requires that appropriate numbers of the correct types of neuronal and glial cells are generated in their proper places and times during development. In the embryonic CNS, multipotent progenitor cells first acquire regional identities, and then undergo precisely choreographed temporal identity transitions (i.e. time-dependent changes in their identity) that determine how many neuronal and glial cells of each type they will generate. Transcription factors of the basic-helix-loop-helix (bHLH) family have emerged as key determinants of neural cell fate specification and differentiation, ensuring that appropriate numbers of specific neuronal and glial cell types are produced. Recent studies have further revealed that the functions of these bHLH factors are strictly regulated. Given their essential developmental roles, it is not surprising that bHLH mutations and de-regulated expression are associated with various neurological diseases and cancers. Moreover, the powerful ability of bHLH factors to direct neuronal and glial cell fate specification and differentiation has been exploited in the relatively new field of cellular reprogramming, in which pluripotent stem cells or somatic stem cells are converted to neural lineages, often with a transcription factor-based lineage conversion strategy that includes one or more of the bHLH genes. These concepts are reviewed herein.
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Affiliation(s)
- Daniel J Dennis
- Sunnybrook Research Institute, 2075 Bayview Ave, Toronto, ON M4N3M5, Canada
| | - Sisu Han
- Sunnybrook Research Institute, 2075 Bayview Ave, Toronto, ON M4N3M5, Canada; Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Carol Schuurmans
- Sunnybrook Research Institute, 2075 Bayview Ave, Toronto, ON M4N3M5, Canada; Department of Biochemistry, University of Toronto, Toronto, ON, Canada.
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35
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Avansini SH, Torres FR, Vieira AS, Dogini DB, Rogerio F, Coan AC, Morita ME, Guerreiro MM, Yasuda CL, Secolin R, Carvalho BS, Borges MG, Almeida VS, Araújo PAOR, Queiroz L, Cendes F, Lopes-Cendes I. Dysregulation of NEUROG2 plays a key role in focal cortical dysplasia. Ann Neurol 2018; 83:623-635. [PMID: 29461643 PMCID: PMC5901021 DOI: 10.1002/ana.25187] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Revised: 02/16/2018] [Accepted: 02/16/2018] [Indexed: 12/31/2022]
Abstract
OBJECTIVE Focal cortical dysplasias (FCDs) are an important cause of drug-resistant epilepsy. In this work, we aimed to investigate whether abnormal gene regulation, mediated by microRNA, could be involved in FCD type II. METHODS We used total RNA from the brain tissue of 16 patients with FCD type II and 28 controls. MicroRNA expression was initially assessed by microarray. Quantitative polymerase chain reaction, in situ hybridization, luciferase reporter assays, and deep sequencing for genes in the mTOR pathway were performed to validate and further explore our initial study. RESULTS hsa-let-7f (p = 0.039), hsa-miR-31 (p = 0.0078), and hsa-miR34a (p = 0.021) were downregulated in FCD type II, whereas a transcription factor involved in neuronal and glial fate specification, NEUROG2 (p < 0.05), was upregulated. We also found that the RND2 gene, a NEUROG2-target, is upregulated (p < 0.001). In vitro experiments showed that hsa-miR-34a downregulates NEUROG2 by binding to its 5'-untranslated region. Moreover, we observed strong nuclear expression of NEUROG2 in balloon cells and dysmorphic neurons and found that 28.5% of our patients presented brain somatic mutations in genes of the mTOR pathway. INTERPRETATION Our findings suggest a new molecular mechanism, in which NEUROG2 has a pivotal and central role in the pathogenesis of FCD type II. In this way, we found that the downregulation of hsa-miR-34a leads to upregulation of NEUROG2, and consequently to overexpression of the RND2 gene. These findings indicate that a faulty coupling in neuronal differentiation and migration mechanisms may explain the presence of aberrant cells and complete dyslamination in FCD type II. Ann Neurol 2018;83:623-635.
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Affiliation(s)
- Simoni H Avansini
- Department of Medical Genetics, University of Campinas and Brazilian Institute of Neuroscience and Neurotechnology, Campinas, Brazil
| | - Fábio R Torres
- Department of Medical Genetics, University of Campinas and Brazilian Institute of Neuroscience and Neurotechnology, Campinas, Brazil
| | - André S Vieira
- Department of Medical Genetics, University of Campinas and Brazilian Institute of Neuroscience and Neurotechnology, Campinas, Brazil
| | - Danyella B Dogini
- Department of Medical Genetics, University of Campinas and Brazilian Institute of Neuroscience and Neurotechnology, Campinas, Brazil
| | - Fabio Rogerio
- Department of Anatomical Pathology, University of Campinas and Brazilian Institute of Neuroscience and Neurotechnology, Campinas, Brazil
| | - Ana C Coan
- Department of Neurology, University of Campinas and Brazilian Institute of Neuroscience and Neurotechnology, Campinas, Brazil
| | - Marcia E Morita
- Department of Neurology, University of Campinas and Brazilian Institute of Neuroscience and Neurotechnology, Campinas, Brazil
| | - Marilisa M Guerreiro
- Department of Neurology, University of Campinas and Brazilian Institute of Neuroscience and Neurotechnology, Campinas, Brazil
| | - Clarissa L Yasuda
- Department of Neurology, University of Campinas and Brazilian Institute of Neuroscience and Neurotechnology, Campinas, Brazil
| | - Rodrigo Secolin
- Department of Medical Genetics, University of Campinas and Brazilian Institute of Neuroscience and Neurotechnology, Campinas, Brazil
| | - Benilton S Carvalho
- Department of Medical Genetics, University of Campinas and Brazilian Institute of Neuroscience and Neurotechnology, Campinas, Brazil
| | - Murilo G Borges
- Department of Medical Genetics, University of Campinas and Brazilian Institute of Neuroscience and Neurotechnology, Campinas, Brazil
| | - Vanessa S Almeida
- Department of Medical Genetics, University of Campinas and Brazilian Institute of Neuroscience and Neurotechnology, Campinas, Brazil
| | - Patrícia A O R Araújo
- Department of Medical Genetics, University of Campinas and Brazilian Institute of Neuroscience and Neurotechnology, Campinas, Brazil
| | - Luciano Queiroz
- Department of Anatomical Pathology, University of Campinas and Brazilian Institute of Neuroscience and Neurotechnology, Campinas, Brazil
| | - Fernando Cendes
- Department of Neurology, University of Campinas and Brazilian Institute of Neuroscience and Neurotechnology, Campinas, Brazil
| | - Iscia Lopes-Cendes
- Department of Medical Genetics, University of Campinas and Brazilian Institute of Neuroscience and Neurotechnology, Campinas, Brazil
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Chouchane M, Costa MR. Instructing neuronal identity during CNS development and astroglial-lineage reprogramming: Roles of NEUROG2 and ASCL1. Brain Res 2018; 1705:66-74. [PMID: 29510143 DOI: 10.1016/j.brainres.2018.02.045] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Revised: 02/16/2018] [Accepted: 02/27/2018] [Indexed: 01/02/2023]
Abstract
The adult mammalian brain contains an enormous variety of neuronal types, which are generally categorized in large groups, based on their neurochemical identity, hodological properties and molecular markers. This broad classification has allowed the correlation between individual neural progenitor populations and their neuronal progeny, thus contributing to probe the cellular and molecular mechanisms involved in neuronal identity determination during central nervous system (CNS) development. In this review, we discuss the contribution of the proneural genes Neurogenin2 (Neurog2) and Achaete-scute homolog 1 (Ascl1) for the specification of neuronal phenotypes in the developing neocortex, cerebellum and retina. Then, we revise recent data on astroglia cell lineage reprogramming into induced neurons using the same proneural proteins to compare the neuronal phenotypes obtained from astroglial cells originated in those CNS regions. We conclude that Ascl1 and Neurog2 have different contributions to determine neuronal fates, depending on the neural progenitor or astroglial population expressing those proneural factors. Finally, we discuss some possible explanations for these seemingly conflicting effects of Ascl1 and Neurog2 and propose future approaches to further dissect the molecular mechanisms of neuronal identity specification.
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Affiliation(s)
- Malek Chouchane
- Brain Institute, Federal University of Rio Grande do Norte, Natal 59072-970, Brazil; Neurological Surgery Department, University of California, San Francisco 94158, USA
| | - Marcos R Costa
- Brain Institute, Federal University of Rio Grande do Norte, Natal 59072-970, Brazil.
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37
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Adnani L, Han S, Li S, Mattar P, Schuurmans C. Mechanisms of Cortical Differentiation. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2018; 336:223-320. [DOI: 10.1016/bs.ircmb.2017.07.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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38
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Pfurr S, Chu YH, Bohrer C, Greulich F, Beattie R, Mammadzada K, Hils M, Arnold SJ, Taylor V, Schachtrup K, Uhlenhaut NH, Schachtrup C. The E2A splice variant E47 regulates the differentiation of projection neurons via p57(KIP2) during cortical development. Development 2017; 144:3917-3931. [PMID: 28939666 DOI: 10.1242/dev.145698] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Accepted: 09/11/2017] [Indexed: 02/01/2023]
Abstract
During corticogenesis, distinct classes of neurons are born from progenitor cells located in the ventricular and subventricular zones, from where they migrate towards the pial surface to assemble into highly organized layer-specific circuits. However, the precise and coordinated transcriptional network activity defining neuronal identity is still not understood. Here, we show that genetic depletion of the basic helix-loop-helix (bHLH) transcription factor E2A splice variant E47 increased the number of Tbr1-positive deep layer and Satb2-positive upper layer neurons at E14.5, while depletion of the alternatively spliced E12 variant did not affect layer-specific neurogenesis. While ChIP-Seq identified a big overlap for E12- and E47-specific binding sites in embryonic NSCs, including sites at the cyclin-dependent kinase inhibitor (CDKI) Cdkn1c gene locus, RNA-Seq revealed a unique transcriptional regulation by each splice variant. E47 activated the expression of the CDKI Cdkn1c through binding to a distal enhancer. Finally, overexpression of E47 in embryonic NSCs in vitro impaired neurite outgrowth, and overexpression of E47 in vivo by in utero electroporation disturbed proper layer-specific neurogenesis and upregulated p57(KIP2) expression. Overall, this study identifies E2A target genes in embryonic NSCs and demonstrates that E47 regulates neuronal differentiation via p57(KIP2).
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Affiliation(s)
- Sabrina Pfurr
- Institute of Anatomy and Cell Biology, Faculty of Medicine, University of Freiburg, Freiburg 79104, Germany.,Faculty of Biology, University of Freiburg, Freiburg 79104, Germany
| | - Yu-Hsuan Chu
- Institute of Anatomy and Cell Biology, Faculty of Medicine, University of Freiburg, Freiburg 79104, Germany.,Faculty of Biology, University of Freiburg, Freiburg 79104, Germany
| | - Christian Bohrer
- Institute of Anatomy and Cell Biology, Faculty of Medicine, University of Freiburg, Freiburg 79104, Germany.,Faculty of Biology, University of Freiburg, Freiburg 79104, Germany
| | - Franziska Greulich
- Helmholtz Diabetes Center (HDC) and German Center for Diabetes Research (DZD), Helmholtz Zentrum München, Neuherberg 85764, Germany
| | - Robert Beattie
- Department of Biomedicine, Embryology and Stem Cell Biology, University of Basel, Basel 4058, Switzerland
| | - Könül Mammadzada
- Institute of Anatomy and Cell Biology, Faculty of Medicine, University of Freiburg, Freiburg 79104, Germany.,Faculty of Biology, University of Freiburg, Freiburg 79104, Germany
| | - Miriam Hils
- Faculty of Biology, University of Freiburg, Freiburg 79104, Germany.,Center for Chronic Immunodeficiency (CCI), Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg 79106, Germany
| | - Sebastian J Arnold
- Institute of Experimental and Clinical Pharmacology and Toxicology, Faculty of Medicine, University of Freiburg, Freiburg 79104, Germany.,BIOSS Centre of Biological Signalling Studies, Albert-Ludwigs-University, Freiburg 79104, Germany
| | - Verdon Taylor
- Department of Biomedicine, Embryology and Stem Cell Biology, University of Basel, Basel 4058, Switzerland
| | - Kristina Schachtrup
- Faculty of Biology, University of Freiburg, Freiburg 79104, Germany.,Center for Chronic Immunodeficiency (CCI), Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg 79106, Germany
| | - N Henriette Uhlenhaut
- Helmholtz Diabetes Center (HDC) and German Center for Diabetes Research (DZD), Helmholtz Zentrum München, Neuherberg 85764, Germany
| | - Christian Schachtrup
- Institute of Anatomy and Cell Biology, Faculty of Medicine, University of Freiburg, Freiburg 79104, Germany
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Neurog2 and Ascl1 together regulate a postmitotic derepression circuit to govern laminar fate specification in the murine neocortex. Proc Natl Acad Sci U S A 2017; 114:E4934-E4943. [PMID: 28584103 DOI: 10.1073/pnas.1701495114] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
A derepression mode of cell-fate specification involving the transcriptional repressors Tbr1, Fezf2, Satb2, and Ctip2 operates in neocortical projection neurons to specify six layer identities in sequence. Less well understood is how laminar fate transitions are regulated in cortical progenitors. The proneural genes Neurog2 and Ascl1 cooperate in progenitors to control the temporal switch from neurogenesis to gliogenesis. Here we asked whether these proneural genes also regulate laminar fate transitions. Several defects were observed in the derepression circuit in Neurog2-/-;Ascl1-/- mutants: an inability to repress expression of Tbr1 (a deep layer VI marker) during upper-layer neurogenesis, a loss of Fezf2+/Ctip2+ layer V neurons, and precocious differentiation of normally late-born, Satb2+ layer II-IV neurons. Conversely, in stable gain-of-function transgenics, Neurog2 promoted differentiative divisions and extended the period of Tbr1+/Ctip2+ deep-layer neurogenesis while reducing Satb2+ upper-layer neurogenesis. Similarly, acute misexpression of Neurog2 in early cortical progenitors promoted Tbr1 expression, whereas both Neurog2 and Ascl1 induced Ctip2. However, Neurog2 was unable to influence the derepression circuit when misexpressed in late cortical progenitors, and Ascl1 repressed only Satb2. Nevertheless, neurons derived from late misexpression of Neurog2 and, to a lesser extent, Ascl1, extended aberrant subcortical axon projections characteristic of early-born neurons. Finally, Neurog2 and Ascl1 altered the expression of Ikaros and Foxg1, known temporal regulators. Proneural genes thus act in a context-dependent fashion as early determinants, promoting deep-layer neurogenesis in early cortical progenitors via input into the derepression circuit while also influencing other temporal regulators.
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Guillemot F, Hassan BA. Beyond proneural: emerging functions and regulations of proneural proteins. Curr Opin Neurobiol 2016; 42:93-101. [PMID: 28025176 DOI: 10.1016/j.conb.2016.11.011] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Revised: 11/25/2016] [Accepted: 11/28/2016] [Indexed: 11/28/2022]
Abstract
Proneural proteins, which include Ascl1, Atoh1 and Neurogenins épinière in vertebrates and Achaete-Scute proteins and Atonal in Drosophila, are expressed in the developing nervous system throughout the animal kingdom and have an essential and well-characterised role in specifying the neural identity of progenitors. New properties and additional roles of these factors have emerged in recent years, including the regulation of stem cell proliferation and the capacity to reprogram many types of cells into neurons. This review will focus on these recent findings. The review will also discuss the mechanisms that allow proneural proteins to induce the transcription of their target genes in different chromatin contexts and the phosphorylation events and other post-transcriptional mechanisms that regulate the proneural proteins themselves.
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Affiliation(s)
| | - Bassem A Hassan
- Sorbonne Universités, UPMC Univ Paris 06, Inserm, CNRS, Institut du Cerveau et la Moëlle Epinière (ICM) - Hôpital Pitié-Salpêtrière, Boulevard de l'hôpital, F-75013 Paris, France.
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41
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Smith DK, Yang J, Liu ML, Zhang CL. Small Molecules Modulate Chromatin Accessibility to Promote NEUROG2-Mediated Fibroblast-to-Neuron Reprogramming. Stem Cell Reports 2016; 7:955-969. [PMID: 28157484 PMCID: PMC5106529 DOI: 10.1016/j.stemcr.2016.09.013] [Citation(s) in RCA: 85] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Revised: 09/28/2016] [Accepted: 09/29/2016] [Indexed: 11/20/2022] Open
Abstract
Pro-neural transcription factors and small molecules can induce the reprogramming of fibroblasts into functional neurons; however, the immediate-early molecular events that catalyze this conversion have not been well defined. We previously demonstrated that neurogenin 2 (NEUROG2), forskolin (F), and dorsomorphin (D) can reprogram fibroblasts into functional neurons with high efficiency. Here, we used this model to define the genetic and epigenetic events that initiate an acquisition of neuronal identity. We demonstrate that NEUROG2 is a pioneer factor, FD enhances chromatin accessibility and H3K27 acetylation, and synergistic transcription activated by these factors is essential to successful reprogramming. CREB1 promotes neuron survival and acts with NEUROG2 to upregulate SOX4, which co-activates NEUROD1 and NEUROD4. In addition, SOX4 targets SWI/SNF subunits and SOX4 knockdown results in extensive loss of open chromatin and abolishes reprogramming. Applying these insights, adult human glioblastoma cell and skin fibroblast reprogramming can be improved using SOX4 or chromatin-modifying chemicals. NEUROG2 acts as a pioneer factor to drive neuronal reprogramming ATAC-, ChIP-, and RNA-seq profiling reveals genome-wide mechanisms for reprogramming SOX4 is a critical mediator of chromatin remodeling during reprogramming SOX4 or FK228 can enhance adult human glioblastoma and skin fibroblast reprogramming
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Affiliation(s)
- Derek K Smith
- Department of Molecular Biology, The University of Texas Southwestern Medical Center, 6000 Harry Hines Boulevard, Dallas, TX 75390-9148, USA; Hamon Center for Regenerative Science and Medicine, The University of Texas Southwestern Medical Center, 6000 Harry Hines Boulevard, Dallas, TX 75390-9148, USA
| | - Jianjing Yang
- Department of Molecular Biology, The University of Texas Southwestern Medical Center, 6000 Harry Hines Boulevard, Dallas, TX 75390-9148, USA; Hamon Center for Regenerative Science and Medicine, The University of Texas Southwestern Medical Center, 6000 Harry Hines Boulevard, Dallas, TX 75390-9148, USA
| | - Meng-Lu Liu
- Department of Molecular Biology, The University of Texas Southwestern Medical Center, 6000 Harry Hines Boulevard, Dallas, TX 75390-9148, USA; Hamon Center for Regenerative Science and Medicine, The University of Texas Southwestern Medical Center, 6000 Harry Hines Boulevard, Dallas, TX 75390-9148, USA
| | - Chun-Li Zhang
- Department of Molecular Biology, The University of Texas Southwestern Medical Center, 6000 Harry Hines Boulevard, Dallas, TX 75390-9148, USA; Hamon Center for Regenerative Science and Medicine, The University of Texas Southwestern Medical Center, 6000 Harry Hines Boulevard, Dallas, TX 75390-9148, USA.
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Shirakawa M, Ueda H, Shimada T, Hara-Nishimura I. FAMA: A Molecular Link between Stomata and Myrosin Cells. TRENDS IN PLANT SCIENCE 2016; 21:861-871. [PMID: 27477926 DOI: 10.1016/j.tplants.2016.07.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Revised: 06/24/2016] [Accepted: 07/04/2016] [Indexed: 05/04/2023]
Abstract
Plants use sophisticated defense strategies against herbivores, including the myrosinase-glucosinolate system in Brassicales plants. This system sequesters myrosinase in myrosin cells, which are idioblasts in inner leaf tissues, and produces a toxic compound when cells are damaged by herbivores. Although the molecular mechanisms underlying myrosin cell development are largely unknown, recent studies have revealed that two key components, a basic helix-loop-helix (bHLH) transcription factor (FAMA) and vesicle trafficking factors (such as SYNTAXIN OF PLANTS 22), regulate the differentiation and fate determination of myrosin cells. FAMA also functions as a master regulator of guard cell (GC) differentiation. In this review, we discuss how FAMA operates two distinct genetic programs: the generation of myrosin cells in inner plant tissue and GCs in the epidermis.
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Affiliation(s)
- Makoto Shirakawa
- Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Haruko Ueda
- Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Tomoo Shimada
- Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
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Dennis D, Picketts D, Slack RS, Schuurmans C. Forebrain neurogenesis: From embryo to adult. TRENDS IN DEVELOPMENTAL BIOLOGY 2016; 9:77-90. [PMID: 28367004 PMCID: PMC5373848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
A satellite symposium to the Canadian Developmental Biology Conference 2016 was held on March 16-17, 2016 in Banff, Alberta, Canada, entitled Forebrain Neurogenesis: From embryo to adult. The Forebrain Neurogenesis symposium was a focused, high-intensity meeting, bringing together the top Canadian and international researchers in the field. This symposium reported the latest breaking news, along with 'state of the art' techniques to answer fundamental questions in developmental neurobiology. Topics covered ranged from stem cell regulation to neurocircuitry development, culminating with a session focused on neuropsychiatric disorders. Understanding the underlying causes of neurodevelopmental disorders such as autism spectrum disorder (ASD) and attention deficit/hyperactivity disorder (ADHD) is of great interest as diagnoses of these conditions are climbing at alarming rates. For instance, in 2012, the Centers for Disease Control reported that the prevalence rate of ASD in the U.S. was 1 in 88; while more recent data indicate that the number is as high as 1 in 68 (Centers for Disease Control and Prevention MMWR Surveillance Summaries. Vol. 63. No. 2). Similarly, the incidence of ASD is on the rise in Canada, increasing from 1 in 150 in 2000 to 1 in 63 in 2012 in southeastern Ontario (Centers for Disease Control and Prevention). Currently very little is known regarding the deficits underlying these neurodevelopmental conditions. Moreover, the development of effective therapies is further limited by major gaps in our understanding of the fundamental processes that regulate forebrain development and adult neurogenesis. The Forebrain Neurogenesis satellite symposium was thus timely, and it played a key role in advancing research in this important field, while also fostering collaborations between international leaders, and inspiring young researchers.
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Affiliation(s)
- Daniel Dennis
- Department of Biochemistry and Molecular Biology, Hotchkiss Brain Institute (HBI), Alberta Children's Hospital Research Institute (ACHRI), University of Calgary, Calgary, Alberta
| | - David Picketts
- Ottawa Hospital Research Institute, Ottawa, Ontario; Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario
| | - Ruth S Slack
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario
| | - Carol Schuurmans
- Department of Biochemistry and Molecular Biology, Hotchkiss Brain Institute (HBI), Alberta Children's Hospital Research Institute (ACHRI), University of Calgary, Calgary, Alberta; Sunnybrook Research Institute, Biological Sciences, Toronto, Ontario, Canada
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Quan XJ, Yuan L, Tiberi L, Claeys A, De Geest N, Yan J, van der Kant R, Xie W, Klisch T, Shymkowitz J, Rousseau F, Bollen M, Beullens M, Zoghbi H, Vanderhaeghen P, Hassan B. Post-translational Control of the Temporal Dynamics of Transcription Factor Activity Regulates Neurogenesis. Cell 2016; 164:460-75. [DOI: 10.1016/j.cell.2015.12.048] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2015] [Revised: 10/12/2015] [Accepted: 12/22/2015] [Indexed: 11/28/2022]
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Abstract
Imprinted genes are dosage sensitive, and their dysregulated expression is linked to disorders of growth and proliferation, including fetal and postnatal growth restriction. Common sequelae of growth disorders include neurodevelopmental defects, some of which are indirectly related to placental insufficiency. However, several growth-associated imprinted genes are also expressed in the embryonic CNS, in which their aberrant expression may more directly affect neurodevelopment. To test whether growth-associated genes influence neural lineage progression, we focused on the maternally imprinted gene Zac1. In humans, either loss or gain of ZAC1 expression is associated with reduced growth rates and intellectual disability. To test whether increased Zac1 expression directly perturbs neurodevelopment, we misexpressed Zac1 in murine neocortical progenitors. The effects were striking: Zac1 delayed the transition of apical radial glial cells to basal intermediate neuronal progenitors and postponed their subsequent differentiation into neurons. Zac1 misexpression also blocked neuronal migration, with Zac1-overexpressing neurons pausing more frequently and forming fewer neurite branches during the period when locomoting neurons undergo dynamic morphological transitions. Similar, albeit less striking, neuronal migration and morphological defects were observed on Zac1 knockdown, indicating that Zac1 levels must be regulated precisely. Finally, Zac1 controlled neuronal migration by regulating Pac1 transcription, a receptor for the neuropeptide pituitary adenylate cyclase-activating polypeptide (PACAP). Pac1 and Zac1 loss- and gain-of-function presented as phenocopies, and overexpression of Pac1 rescued the Zac1 knockdown neuronal migration phenotype. Thus, dysregulated Zac1 expression has striking consequences on neocortical development, suggesting that misexpression of this transcription factor in the brain in certain growth disorders may contribute to neurocognitive deficits. Significance statement: Altered expression of imprinted genes is linked to cognitive dysfunction and neuropsychological disorders, such as Angelman and Prader-Willi syndromes, and autism spectrum disorder. Mouse models have also revealed the importance of imprinting for brain development, with chimeras generated with parthenogenetic (two maternal chromosomes) or androgenetic (two paternal chromosomes) cells displaying altered brain sizes and cellular defects. Despite these striking phenotypes, only a handful of imprinted genes are known or suspected to regulate brain development (e.g., Dlk1, Peg3, Ube3a, necdin, and Grb10). Herein we show that the maternally imprinted gene Zac1 is a critical regulator of neocortical development. Our studies are relevant because loss of 6q24 maternal imprinting in humans results in elevated ZAC1 expression, which has been associated with neurocognitive defects.
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Small Molecules Efficiently Reprogram Human Astroglial Cells into Functional Neurons. Cell Stem Cell 2015; 17:735-747. [PMID: 26481520 DOI: 10.1016/j.stem.2015.09.012] [Citation(s) in RCA: 221] [Impact Index Per Article: 24.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2014] [Revised: 08/04/2015] [Accepted: 09/15/2015] [Indexed: 01/19/2023]
Abstract
We have recently demonstrated that reactive glial cells can be directly reprogrammed into functional neurons by a single neural transcription factor, NeuroD1. Here we report that a combination of small molecules can also reprogram human astrocytes in culture into fully functional neurons. We demonstrate that sequential exposure of human astrocytes to a cocktail of nine small molecules that inhibit glial but activate neuronal signaling pathways can successfully reprogram astrocytes into neurons in 8-10 days. This chemical reprogramming is mediated through epigenetic regulation and involves transcriptional activation of NEUROD1 and NEUROGENIN2. The human astrocyte-converted neurons can survive for >5 months in culture and form functional synaptic networks with synchronous burst activities. The chemically reprogrammed human neurons can also survive for >1 month in the mouse brain in vivo and integrate into local circuits. Our study opens a new avenue using chemical compounds to reprogram reactive glial cells into functional neurons.
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47
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Kiparaki M, Zarifi I, Delidakis C. bHLH proteins involved in Drosophila neurogenesis are mutually regulated at the level of stability. Nucleic Acids Res 2015; 43:2543-59. [PMID: 25694512 PMCID: PMC4357701 DOI: 10.1093/nar/gkv083] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Proneural bHLH activators are expressed in all neuroectodermal regions prefiguring events of central and peripheral neurogenesis. Drosophila Sc is a prototypical proneural activator that heterodimerizes with the E-protein Daughterless (Da) and is antagonized by, among others, the E(spl) repressors. We determined parameters that regulate Sc stability in Drosophila S2 cells. We found that Sc is a very labile phosphoprotein and its turnover takes place via at least three proteasome-dependent mechanisms. (i) When Sc is in excess of Da, its degradation is promoted via its transactivation domain (TAD). (ii) In a DNA-bound Da/Sc heterodimer, Sc degradation is promoted via an SPTSS phosphorylation motif and the AD1 TAD of Da; Da is spared in the process. (iii) When E(spl)m7 is expressed, it complexes with Sc or Da/Sc and promotes their degradation in a manner that requires the corepressor Groucho and the Sc SPTSS motif. Da/Sc reciprocally promotes E(spl)m7 degradation. Since E(spl)m7 is a direct target of Notch, the mutual destabilization of Sc and E(spl) may contribute in part to the highly conserved anti-neural activity of Notch. Sc variants lacking the SPTSS motif are dramatically stabilized and are hyperactive in transgenic flies. Our results propose a novel mechanism of regulation of neurogenesis, involving the stability of key players in the process.
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Affiliation(s)
- Marianthi Kiparaki
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology Hellas, and Department of Biology, University of Crete, 70013 Heraklion, Crete, Greece
| | - Ioanna Zarifi
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology Hellas, and Department of Biology, University of Crete, 70013 Heraklion, Crete, Greece
| | - Christos Delidakis
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology Hellas, and Department of Biology, University of Crete, 70013 Heraklion, Crete, Greece
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Efthymiou AG, Steiner J, Pavan WJ, Wincovitch S, Larson DM, Porter FD, Rao MS, Malik N. Rescue of an in vitro neuron phenotype identified in Niemann-Pick disease, type C1 induced pluripotent stem cell-derived neurons by modulating the WNT pathway and calcium signaling. Stem Cells Transl Med 2015; 4:230-8. [PMID: 25637190 DOI: 10.5966/sctm.2014-0127] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Niemann-Pick disease, type C1 (NPC1) is a familial disorder that has devastating consequences on postnatal development with multisystem effects, including neurodegeneration. There is no Food and Drug Administration-approved treatment option for NPC1; however, several potentially therapeutic compounds have been identified in assays using yeast, rodent models, and NPC1 human fibroblasts. Although these discoveries were made in fibroblasts from NPC1 subjects and were in some instances validated in animal models of the disease, testing these drugs on a cell type more relevant for NPC1 neurological disease would greatly facilitate both study of the disease and identification of more relevant therapeutic compounds. Toward this goal, we have generated an induced pluripotent stem cell line from a subject homozygous for the most frequent NPC1 mutation (p.I1061T) and subsequently created a stable line of neural stem cells (NSCs). These NSCs were then used to create neurons as an appropriate disease model. NPC1 neurons display a premature cell death phenotype, and gene expression analysis of these cells suggests dysfunction of important signaling pathways, including calcium and WNT. The clear readout from these cells makes them ideal candidates for high-throughput screening and will be a valuable tool to better understand the development of NPC1 in neural cells, as well as to develop better therapeutic options for NPC1.
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Affiliation(s)
- Anastasia G Efthymiou
- National Institute of Arthritis and Musculoskeletal and Skin Diseases, NeuroTherapeutics Development Unit, National Institute for Neurological Diseases and Stroke, Genetic Disease Research Branch, National Human Genome Research Institute, Eunice Kennedy Shriver National Institute for Child Health and Human Development, and Center for Regenerative Medicine, National Institutes of Health, Bethesda, Maryland, USA
| | - Joe Steiner
- National Institute of Arthritis and Musculoskeletal and Skin Diseases, NeuroTherapeutics Development Unit, National Institute for Neurological Diseases and Stroke, Genetic Disease Research Branch, National Human Genome Research Institute, Eunice Kennedy Shriver National Institute for Child Health and Human Development, and Center for Regenerative Medicine, National Institutes of Health, Bethesda, Maryland, USA
| | - William J Pavan
- National Institute of Arthritis and Musculoskeletal and Skin Diseases, NeuroTherapeutics Development Unit, National Institute for Neurological Diseases and Stroke, Genetic Disease Research Branch, National Human Genome Research Institute, Eunice Kennedy Shriver National Institute for Child Health and Human Development, and Center for Regenerative Medicine, National Institutes of Health, Bethesda, Maryland, USA
| | - Stephen Wincovitch
- National Institute of Arthritis and Musculoskeletal and Skin Diseases, NeuroTherapeutics Development Unit, National Institute for Neurological Diseases and Stroke, Genetic Disease Research Branch, National Human Genome Research Institute, Eunice Kennedy Shriver National Institute for Child Health and Human Development, and Center for Regenerative Medicine, National Institutes of Health, Bethesda, Maryland, USA
| | - Denise M Larson
- National Institute of Arthritis and Musculoskeletal and Skin Diseases, NeuroTherapeutics Development Unit, National Institute for Neurological Diseases and Stroke, Genetic Disease Research Branch, National Human Genome Research Institute, Eunice Kennedy Shriver National Institute for Child Health and Human Development, and Center for Regenerative Medicine, National Institutes of Health, Bethesda, Maryland, USA
| | - Forbes D Porter
- National Institute of Arthritis and Musculoskeletal and Skin Diseases, NeuroTherapeutics Development Unit, National Institute for Neurological Diseases and Stroke, Genetic Disease Research Branch, National Human Genome Research Institute, Eunice Kennedy Shriver National Institute for Child Health and Human Development, and Center for Regenerative Medicine, National Institutes of Health, Bethesda, Maryland, USA
| | - Mahendra S Rao
- National Institute of Arthritis and Musculoskeletal and Skin Diseases, NeuroTherapeutics Development Unit, National Institute for Neurological Diseases and Stroke, Genetic Disease Research Branch, National Human Genome Research Institute, Eunice Kennedy Shriver National Institute for Child Health and Human Development, and Center for Regenerative Medicine, National Institutes of Health, Bethesda, Maryland, USA
| | - Nasir Malik
- National Institute of Arthritis and Musculoskeletal and Skin Diseases, NeuroTherapeutics Development Unit, National Institute for Neurological Diseases and Stroke, Genetic Disease Research Branch, National Human Genome Research Institute, Eunice Kennedy Shriver National Institute for Child Health and Human Development, and Center for Regenerative Medicine, National Institutes of Health, Bethesda, Maryland, USA
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Touahri Y, Adnani L, Mattar P, Markham K, Klenin N, Schuurmans C. Non-isotopic RNA In Situ Hybridization on Embryonic Sections. ACTA ACUST UNITED AC 2015; 70:1.22.1-1.22.25. [PMID: 25559002 DOI: 10.1002/0471142301.ns0122s70] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
This unit describes methods for non-isotopic RNA in situ hybridization on embryonic mouse sections. These methods can be used to follow the spatiotemporal dynamics of gene expression in an embryonic tissue of interest. They involve the use of labeled (e.g., digoxygenin, FITC) antisense riboprobes that hybridize to a specific mRNA in the target tissue. The probes are detected using an alkaline phosphatase-conjugated antibody recognizing the label and a chromogenic substrate. This method can be used to: (1) assess the expression of a single gene within a tissue, (2) compare the expression profiles of two genes within a tissue, or (3) compare the distribution of a transcript and protein within a tissue. While this approach is not quantitative, it provides a qualitative assessment of the precise cell types where a gene is expressed, which is not easily achievable with other more quantitative methods such as quantitative PCR.
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Affiliation(s)
- Yacine Touahri
- Department of Biochemistry and Molecular Biology, Hotchkiss Brain Institute, Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
| | - Lata Adnani
- Department of Biochemistry and Molecular Biology, Hotchkiss Brain Institute, Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
| | - Pierre Mattar
- Department of Biochemistry and Molecular Biology, Hotchkiss Brain Institute, Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada.,Current address: Cellular Neurobiology Research Unit, Institut de Recherches Cliniques de Montréal, Montréal, Quebec, Canada
| | - Kathryn Markham
- Department of Biochemistry and Molecular Biology, Hotchkiss Brain Institute, Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
| | - Natalia Klenin
- Department of Biochemistry and Molecular Biology, Hotchkiss Brain Institute, Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
| | - Carol Schuurmans
- Department of Biochemistry and Molecular Biology, Hotchkiss Brain Institute, Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
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50
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Fischer B, Azim K, Hurtado-Chong A, Ramelli S, Fernández M, Raineteau O. E-proteins orchestrate the progression of neural stem cell differentiation in the postnatal forebrain. Neural Dev 2014; 9:23. [PMID: 25352248 PMCID: PMC4274746 DOI: 10.1186/1749-8104-9-23] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Accepted: 10/08/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Neural stem cell (NSC) differentiation is a complex multistep process that persists in specific regions of the postnatal forebrain and requires tight regulation throughout life. The transcriptional control of NSC proliferation and specification involves Class II (proneural) and Class V (Id1-4) basic helix-loop-helix (bHLH) proteins. In this study, we analyzed the pattern of expression of their dimerization partners, Class I bHLH proteins (E-proteins), and explored their putative role in orchestrating postnatal subventricular zone (SVZ) neurogenesis. RESULTS Overexpression of a dominant-negative form of the E-protein E47 (dnE47) confirmed a crucial role for bHLH transcriptional networks in postnatal neurogenesis by dramatically blocking SVZ NSC differentiation. In situ hybridization was used in combination with RT-qPCR to measure and compare the level of expression of E-protein transcripts (E2-2, E2A, and HEB) in the neonatal and adult SVZ as well as in magnetic affinity cell sorted progenitor cells and neuroblasts. Our results evidence that E-protein transcripts, in particular E2-2 and E2A, are enriched in the postnatal SVZ with expression levels increasing as cells engage towards neuronal differentiation. To investigate the role of E-proteins in orchestrating lineage progression, both in vitro and in vivo gain-of-function and loss-of-function experiments were performed for individual E-proteins. Overexpression of E2-2 and E2A promoted SVZ neurogenesis by enhancing not only radial glial cell differentiation but also cell cycle exit of their progeny. Conversely, knock-down by shRNA electroporation resulted in opposite effects. Manipulation of E-proteins and/or Ascl1 in SVZ NSC cultures indicated that those effects were Ascl1 dependent, although they could not solely be attributed to an Ascl1-induced switch from promoting cell proliferation to triggering cell cycle arrest and differentiation. CONCLUSIONS In contrast to former concepts, suggesting ubiquitous expression and subsidiary function for E-proteins to foster postnatal neurogenesis, this work unveils E-proteins as being active players in the orchestration of postnatal SVZ neurogenesis.
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Affiliation(s)
| | | | | | | | | | - Olivier Raineteau
- Brain Research Institute, ETH Zurich/University of Zurich, 8057 Zurich, Switzerland.
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