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Renaux E, Baudouin C, Schakman O, Gay O, Martin M, Marchese D, Achouri Y, Rezsohazy R, Gofflot F, Clotman F. Arid3c identifies an uncharacterized subpopulation of V2 interneurons during embryonic spinal cord development. Front Cell Neurosci 2024; 18:1466056. [PMID: 39479525 PMCID: PMC11521906 DOI: 10.3389/fncel.2024.1466056] [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: 07/17/2024] [Accepted: 09/26/2024] [Indexed: 11/02/2024] Open
Abstract
Motor activity is organized by neuronal networks composed of motor neurons and a wide variety of pre-motor interneuron populations located in the brainstem and spinal cord. Differential expression and single-cell RNA sequencing studies recently unveiled that these populations subdivide into multiple subsets. However, some interneuron subsets have not been described yet, and the mechanisms contributing to this neuronal diversification have only been partly deciphered. In this study, we aimed to identify additional markers to further describe the diversity of spinal V2 interneuron populations. Here, we compared the transcriptome of V2 interneurons with that of the other cells of the embryonic spinal cord and extracted a list of genes enriched in V2 interneurons, including Arid3c. Arid3c identifies an uncharacterized subset of V2 that partially overlaps with V2c interneurons. These two populations are characterized by the production of Onecut factors and Sox2, suggesting that they could represent a single functional V2 unit. Furthermore, we show that the overexpression or inactivation of Arid3c does not alter V2 production, but its absence results in minor defects in locomotor execution, suggesting a possible function in subtle aspects of spinal locomotor circuit formation.
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Affiliation(s)
- Estelle Renaux
- Université catholique de Louvain, Louvain Institute of Biomolecular Science and Technology, Animal Molecular and Cellular Biology group, Louvain-la-Neuve, Belgium
- Université catholique de Louvain, Institute of Neuroscience, Laboratory of Neural Differentiation, Brussels, Belgium
| | - Charlotte Baudouin
- Université catholique de Louvain, Institute of Neuroscience, Laboratory of Neural Differentiation, Brussels, Belgium
| | - Olivier Schakman
- Université catholique de Louvain, Institute of Neuroscience, Behavioral Analysis Platform (BEAP), Brussels, Belgium
| | - Ondine Gay
- Master de Biologie, École Normale Supérieure de Lyon, Université Claude Bernard Lyon 1, Université de Lyon, Lyon Cedex, France
| | - Manon Martin
- Université catholique de Louvain, Louvain Institute of Biomolecular Science and Technology, Louvain-la-Neuve, Belgium
| | - Damien Marchese
- Université catholique de Louvain, Louvain Institute of Biomolecular Science and Technology, Animal Molecular and Cellular Biology group, Louvain-la-Neuve, Belgium
| | - Younès Achouri
- Université catholique de Louvain, de Duve Institute, Transgenic Core Facility, Brussels, Belgium
| | - René Rezsohazy
- Université catholique de Louvain, Louvain Institute of Biomolecular Science and Technology, Animal Molecular and Cellular Biology group, Louvain-la-Neuve, Belgium
| | - Françoise Gofflot
- Université catholique de Louvain, Louvain Institute of Biomolecular Science and Technology, Animal Molecular and Cellular Biology group, Louvain-la-Neuve, Belgium
| | - Frédéric Clotman
- Université catholique de Louvain, Louvain Institute of Biomolecular Science and Technology, Animal Molecular and Cellular Biology group, Louvain-la-Neuve, Belgium
- Université catholique de Louvain, Institute of Neuroscience, Laboratory of Neural Differentiation, Brussels, Belgium
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Zhu M, Meglicki M, Lamba A, Wang P, Royer C, Turner K, Jauhar MA, Jones C, Child T, Coward K, Na J, Zernicka-Goetz M. Tead4 and Tfap2c generate bipotency and a bistable switch in totipotent embryos to promote robust lineage diversification. Nat Struct Mol Biol 2024; 31:964-976. [PMID: 38789684 PMCID: PMC11189297 DOI: 10.1038/s41594-024-01311-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Accepted: 04/09/2024] [Indexed: 05/26/2024]
Abstract
The mouse and human embryo gradually loses totipotency before diversifying into the inner cell mass (ICM, future organism) and trophectoderm (TE, future placenta). The transcription factors TFAP2C and TEAD4 with activated RHOA accelerate embryo polarization. Here we show that these factors also accelerate the loss of totipotency. TFAP2C and TEAD4 paradoxically promote and inhibit Hippo signaling before lineage diversification: they drive expression of multiple Hippo regulators while also promoting apical domain formation, which inactivates Hippo. Each factor activates TE specifiers in bipotent cells, while TFAP2C also activates specifiers of the ICM fate. Asymmetric segregation of the apical domain reconciles the opposing regulation of Hippo signaling into Hippo OFF and the TE fate, or Hippo ON and the ICM fate. We propose that the bistable switch established by TFAP2C and TEAD4 is exploited to trigger robust lineage diversification in the developing embryo.
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Affiliation(s)
- Meng Zhu
- Mammalian Embryo and Stem Cell Group, Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, UK
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - Maciej Meglicki
- Mammalian Embryo and Stem Cell Group, Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, UK
| | - Adiyant Lamba
- Mammalian Embryo and Stem Cell Group, Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, UK
| | - Peizhe Wang
- Centre for Stem Cell Biology and Regenerative Medicine, School of Medicine, Tsinghua University, Beijing, China
| | - Christophe Royer
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
| | - Karen Turner
- Oxford Fertility, Institute of Reproductive Sciences, Oxford, UK
| | - Muhammad Abdullah Jauhar
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Celine Jones
- Nuffield Department of Women's and Reproductive Health, Level 3, Women's Centre, John Radcliffe Hospital, University of Oxford, Oxford, UK
| | - Tim Child
- Nuffield Department of Women's and Reproductive Health, Level 3, Women's Centre, John Radcliffe Hospital, University of Oxford, Oxford, UK
| | - Kevin Coward
- Nuffield Department of Women's and Reproductive Health, Level 3, Women's Centre, John Radcliffe Hospital, University of Oxford, Oxford, UK
| | - Jie Na
- Centre for Stem Cell Biology and Regenerative Medicine, School of Medicine, Tsinghua University, Beijing, China
| | - Magdalena Zernicka-Goetz
- Mammalian Embryo and Stem Cell Group, Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, UK.
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA.
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Kurtova AI, Finoshin AD, Aparina MS, Gazizova GR, Kozlova OS, Voronova SN, Shagimardanova EI, Ivashkin EG, Voronezhskaya EE. Expanded expression of pro-neurogenic factor SoxB1 during larval development of gastropod Lymnaea stagnalis suggests preadaptation to prolonged neurogenesis in Mollusca. Front Neurosci 2024; 18:1346610. [PMID: 38638695 PMCID: PMC11024475 DOI: 10.3389/fnins.2024.1346610] [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: 11/29/2023] [Accepted: 03/01/2024] [Indexed: 04/20/2024] Open
Abstract
Introduction The remarkable diversity observed in the structure and development of the molluscan nervous system raises intriguing questions regarding the molecular mechanisms underlying neurogenesis in Mollusca. The expression of SoxB family transcription factors plays a pivotal role in neuronal development, thereby offering valuable insights into the strategies of neurogenesis. Methods In this study, we conducted gene expression analysis focusing on SoxB-family transcription factors during early neurogenesis in the gastropod Lymnaea stagnalis. We employed a combination of hybridization chain reaction in situ hybridization (HCR-ISH), immunocytochemistry, confocal microscopy, and cell proliferation assays to investigate the spatial and temporal expression patterns of LsSoxB1 and LsSoxB2 from the gastrula stage to hatching, with particular attention to the formation of central ring ganglia. Results Our investigation reveals that LsSoxB1 demonstrates expanded ectodermal expression from the gastrula to the hatching stage, whereas expression of LsSoxB2 in the ectoderm ceases by the veliger stage. LsSoxB1 is expressed in the ectoderm of the head, foot, and visceral complex, as well as in forming ganglia and sensory cells. Conversely, LsSoxB2 is mostly restricted to the subepithelial layer and forming ganglia cells during metamorphosis. Proliferation assays indicate a uniform distribution of dividing cells in the ectoderm across all developmental stages, suggesting the absence of distinct neurogenic zones with increased proliferation in gastropods. Discussion Our findings reveal a spatially and temporally extended pattern of SoxB1 expression in a gastropod representative compared to other lophotrochozoan species. This prolonged and widespread expression of SoxB genes may be interpreted as a form of transcriptional neoteny, representing a preadaptation to prolonged neurogenesis. Consequently, it could contribute to the diversification of nervous systems in gastropods and lead to an increase in the complexity of the central nervous system in Mollusca.
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Affiliation(s)
- Anastasia I. Kurtova
- Koltsov Institute of Developmental Biology, Russian Academy of Sciences, Moscow, Russia
| | - Alexander D. Finoshin
- Koltsov Institute of Developmental Biology, Russian Academy of Sciences, Moscow, Russia
| | - Margarita S. Aparina
- Koltsov Institute of Developmental Biology, Russian Academy of Sciences, Moscow, Russia
- Severtsov Institute of Ecology and Evolution, Russian Academy of Sciences, Moscow, Russia
| | - Guzel R. Gazizova
- Regulatory Genomics Research Center, Institute of Fundamental Medicine and Biology, Kazan Federal University, Kazan, Russia
| | - Olga S. Kozlova
- Regulatory Genomics Research Center, Institute of Fundamental Medicine and Biology, Kazan Federal University, Kazan, Russia
| | - Svetlana N. Voronova
- Koltsov Institute of Developmental Biology, Russian Academy of Sciences, Moscow, Russia
| | - Elena I. Shagimardanova
- Regulatory Genomics Research Center, Institute of Fundamental Medicine and Biology, Kazan Federal University, Kazan, Russia
- Life Improvement by Future Technologies Center “LIFT”, Moscow, Russia
- Skolkovo Institute of Science and Technology, Moscow, Russia
| | - Evgeny G. Ivashkin
- Severtsov Institute of Ecology and Evolution, Russian Academy of Sciences, Moscow, Russia
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Cucun G, Köhler M, Pfitsch S, Rastegar S. Insights into the mechanisms of neuron generation and specification in the zebrafish ventral spinal cord. FEBS J 2024; 291:646-662. [PMID: 37498183 DOI: 10.1111/febs.16913] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Revised: 06/20/2023] [Accepted: 07/25/2023] [Indexed: 07/28/2023]
Abstract
The vertebrate nervous system is composed of a wide range of neurons and complex synaptic connections, raising the intriguing question of how neuronal diversity is generated. The spinal cord provides an excellent model for exploring the mechanisms governing neuronal diversity due to its simple neural network and the conserved molecular processes involved in neuron formation and specification during evolution. This review specifically examines two distinct progenitor domains present in the zebrafish ventral spinal cord: the lateral floor plate (LFP) and the p2 progenitor domain. The LFP is responsible for the production of GABAergic Kolmer-Agduhr neurons (KA″), glutamatergic V3 neurons, and intraspinal serotonergic neurons, while the p2 domain generates V2 precursors that subsequently differentiate into three unique subpopulations of V2 neurons, namely glutamatergic V2a, GABAergic V2b, and glycinergic V2s. Based on recent findings, we will examine the fundamental signaling pathways and transcription factors that play a key role in the specification of these diverse neurons and neuronal subtypes derived from the LFP and p2 progenitor domains.
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Affiliation(s)
- Gokhan Cucun
- Institute for Biological and Chemical Systems - Biological Information Processing (IBCS-BIP), Karlsruhe Institute of Technology (KIT), Eggenstein-Leopoldshafen, Germany
| | - Melina Köhler
- Institute for Biological and Chemical Systems - Biological Information Processing (IBCS-BIP), Karlsruhe Institute of Technology (KIT), Eggenstein-Leopoldshafen, Germany
| | - Sabrina Pfitsch
- Institute for Biological and Chemical Systems - Biological Information Processing (IBCS-BIP), Karlsruhe Institute of Technology (KIT), Eggenstein-Leopoldshafen, Germany
| | - Sepand Rastegar
- Institute for Biological and Chemical Systems - Biological Information Processing (IBCS-BIP), Karlsruhe Institute of Technology (KIT), Eggenstein-Leopoldshafen, Germany
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5
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Chen F, Köhler M, Cucun G, Takamiya M, Kizil C, Cosacak MI, Rastegar S. sox1a:eGFP transgenic line and single-cell transcriptomics reveal the origin of zebrafish intraspinal serotonergic neurons. iScience 2023; 26:107342. [PMID: 37529101 PMCID: PMC10387610 DOI: 10.1016/j.isci.2023.107342] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 06/03/2023] [Accepted: 07/06/2023] [Indexed: 08/03/2023] Open
Abstract
Sox transcription factors are crucial for vertebrate nervous system development. In zebrafish embryo, sox1 genes are expressed in neural progenitor cells and neurons of ventral spinal cord. Our recent study revealed that the loss of sox1a and sox1b function results in a significant decline of V2 subtype neurons (V2s). Using single-cell RNA sequencing, we analyzed the transcriptome of sox1a lineage progenitors and neurons in the zebrafish spinal cord at four time points during embryonic development, employing the Tg(sox1a:eGFP) line. In addition to previously characterized sox1a-expressing neurons, we discovered the expression of sox1a in late-developing intraspinal serotonergic neurons (ISNs). Developmental trajectory analysis suggests that ISNs arise from lateral floor plate (LFP) progenitor cells. Pharmacological inhibition of the Notch signaling pathway revealed its role in negatively regulating LFP progenitor cell differentiation into ISNs. Our findings highlight the zebrafish LFP as a progenitor domain for ISNs, alongside known Kolmer-Agduhr (KA) and V3 interneurons.
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Affiliation(s)
- Fushun Chen
- Institute of Biological and Chemical Systems-Biological Information Processing (IBCS-BIP), Karlsruhe Institute of Technology (KIT), Campus North, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
| | - Melina Köhler
- Institute of Biological and Chemical Systems-Biological Information Processing (IBCS-BIP), Karlsruhe Institute of Technology (KIT), Campus North, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
| | - Gokhan Cucun
- Institute of Biological and Chemical Systems-Biological Information Processing (IBCS-BIP), Karlsruhe Institute of Technology (KIT), Campus North, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
| | - Masanari Takamiya
- Institute of Biological and Chemical Systems-Biological Information Processing (IBCS-BIP), Karlsruhe Institute of Technology (KIT), Campus North, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
| | - Caghan Kizil
- German Center for Neurodegenerative Diseases (DZNE) Dresden, Helmholtz Association, Tatzberg 41, 01307 Dresden, Germany
- Department of Neurology and the Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, Columbia University Irving Medical Center, 630 W 168th Street, New York, NY 10032, USA
| | - Mehmet Ilyas Cosacak
- German Center for Neurodegenerative Diseases (DZNE) Dresden, Helmholtz Association, Tatzberg 41, 01307 Dresden, Germany
| | - Sepand Rastegar
- Institute of Biological and Chemical Systems-Biological Information Processing (IBCS-BIP), Karlsruhe Institute of Technology (KIT), Campus North, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
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6
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Abstract
The spinal cord is home to the intrinsic networks for locomotion. An animal in which the spinal cord has been fully severed from the brain can still produce rhythmic, patterned locomotor movements as long as some excitatory drive is provided, such as physical, pharmacological, or electrical stimuli. Yet it remains a challenge to define the underlying circuitry that produces these movements because the spinal cord contains a wide variety of neuron classes whose patterns of interconnectivity are still poorly understood. Computational models of locomotion accordingly rely on untested assumptions about spinal neuron network element identity and connectivity. In this review, we consider the classes of spinal neurons, their interconnectivity, and the significance of their circuit connections along the long axis of the spinal cord. We suggest several lines of analysis to move toward a definitive understanding of the spinal network.
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Affiliation(s)
- Mohini Sengupta
- Department of Neuroscience, Washington University in St. Louis, St. Louis, Missouri, USA;
| | - Martha W Bagnall
- Department of Neuroscience, Washington University in St. Louis, St. Louis, Missouri, USA;
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7
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Wilson AC, Sweeney LB. Spinal cords: Symphonies of interneurons across species. Front Neural Circuits 2023; 17:1146449. [PMID: 37180760 PMCID: PMC10169611 DOI: 10.3389/fncir.2023.1146449] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Accepted: 03/23/2023] [Indexed: 05/16/2023] Open
Abstract
Vertebrate movement is orchestrated by spinal inter- and motor neurons that, together with sensory and cognitive input, produce dynamic motor behaviors. These behaviors vary from the simple undulatory swimming of fish and larval aquatic species to the highly coordinated running, reaching and grasping of mice, humans and other mammals. This variation raises the fundamental question of how spinal circuits have changed in register with motor behavior. In simple, undulatory fish, exemplified by the lamprey, two broad classes of interneurons shape motor neuron output: ipsilateral-projecting excitatory neurons, and commissural-projecting inhibitory neurons. An additional class of ipsilateral inhibitory neurons is required to generate escape swim behavior in larval zebrafish and tadpoles. In limbed vertebrates, a more complex spinal neuron composition is observed. In this review, we provide evidence that movement elaboration correlates with an increase and specialization of these three basic interneuron types into molecularly, anatomically, and functionally distinct subpopulations. We summarize recent work linking neuron types to movement-pattern generation across fish, amphibians, reptiles, birds and mammals.
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Affiliation(s)
| | - Lora B. Sweeney
- Institute of Science and Technology Austria (IST Austria), Klosterneuburg, Lower Austria, Austria
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8
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Bello-Rojas S, Bagnall MW. Clonally related, Notch-differentiated spinal neurons integrate into distinct circuits. eLife 2022; 11:e83680. [PMID: 36580075 PMCID: PMC9799969 DOI: 10.7554/elife.83680] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Accepted: 11/24/2022] [Indexed: 12/30/2022] Open
Abstract
Shared lineage has diverse effects on patterns of neuronal connectivity. In mammalian cortex, excitatory sister neurons assemble into shared microcircuits. In Drosophila, in contrast, sister neurons with different levels of Notch expression (NotchON/NotchOFF) develop distinct identities and diverge into separate circuits. Notch-differentiated sister neurons have been observed in vertebrate spinal cord and cerebellum, but whether they integrate into shared or distinct circuits remains unknown. Here, we evaluate how sister V2a (NotchOFF)/V2b (NotchON) neurons in the zebrafish integrate into spinal circuits. Using an in vivo labeling approach, we identified pairs of sister V2a/b neurons born from individual Vsx1+ progenitors and observed that they have somata in close proximity to each other and similar axonal trajectories. However, paired whole-cell electrophysiology and optogenetics revealed that sister V2a/b neurons receive input from distinct presynaptic sources, do not communicate with each other, and connect to largely distinct targets. These results resemble the divergent connectivity in Drosophila and represent the first evidence of Notch-differentiated circuit integration in a vertebrate system.
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Affiliation(s)
- Saul Bello-Rojas
- Department of Neuroscience, Washington University in St. LouisSt. LouisUnited States
| | - Martha W Bagnall
- Department of Neuroscience, Washington University in St. LouisSt. LouisUnited States
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9
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Gurram RK, Wei D, Yu Q, Kamenyeva O, Chung H, Zheng M, Butcher MJ, Kabat J, Liu C, Khillan JS, Zhu J. Gata3 ZsG and Gata3 ZsG-fl: Novel murine Gata3 reporter alleles for identifying and studying Th2 cells and ILC2s in vivo. Front Immunol 2022; 13:975958. [PMID: 36466899 PMCID: PMC9709206 DOI: 10.3389/fimmu.2022.975958] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Accepted: 10/31/2022] [Indexed: 10/10/2023] Open
Abstract
T helper-2 (Th2) cells and type 2 innate lymphoid cells (ILC2s) play crucial roles during type 2 immune responses; the transcription factor GATA3 is essential for the differentiation and functions of these cell types. It has been demonstrated that GATA3 is critical for maintaining Th2 and ILC2 phenotype in vitro; GATA3 not only positively regulates type 2 lymphocyte-associated genes, it also negatively regulates many genes associated with other lineages. However, such functions cannot be easily verified in vivo because the expression of the markers for identifying Th2 and ILC2s depends on GATA3. Thus, whether Th2 cells and ILC2s disappear after Gata3 deletion or these Gata3-deleted "Th2 cells" or "ILC2s" acquire an alternative lineage fate is unknown. In this study, we generated novel GATA3 reporter mouse strains carrying the Gata3 ZsG or Gata3 ZsG-fl allele. This was achieved by inserting a ZsGreen-T2A cassette at the translation initiation site of either the wild type Gata3 allele or the modified Gata3 allele which carries two loxP sites flanking the exon 4. ZsGreen faithfully reflected the endogenous GATA3 protein expression in Th2 cells and ILC2s both in vitro and in vivo. These reporter mice also allowed us to visualize Th2 cells and ILC2s in vivo. An inducible Gata3 deletion system was created by crossing Gata3 ZsG-fl/fl mice with a tamoxifen-inducible Cre. Continuous expression of ZsGreen even after the Gata3 exon 4 deletion was noted, which allows us to isolate and monitor GATA3-deficient "Th2" cells and "ILC2s" during in vivo immune responses. Our results not only indicated that functional GATA3 is dispensable for regulating its own expression in mature type 2 lymphocytes, but also revealed that GATA3-deficient "ILC2s" might be much more stable in vivo than in vitro. Overall, the generation of these novel GATA3 reporters will provide valuable research tools to the scientific community in investigating type 2 immune responses in vivo.
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Affiliation(s)
- Rama K. Gurram
- Molecular and Cellular Immunoregulation Section, Laboratory of Immune System Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States
| | - Danping Wei
- Molecular and Cellular Immunoregulation Section, Laboratory of Immune System Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States
| | - Qiao Yu
- Molecular and Cellular Immunoregulation Section, Laboratory of Immune System Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States
- Department of Gerontology and Respirology, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Olena Kamenyeva
- Research Technologies Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States
| | - Hyunwoo Chung
- Molecular and Cellular Immunoregulation Section, Laboratory of Immune System Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States
| | - Mingzhu Zheng
- Molecular and Cellular Immunoregulation Section, Laboratory of Immune System Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States
| | - Matthew J. Butcher
- Molecular and Cellular Immunoregulation Section, Laboratory of Immune System Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States
| | - Juraj Kabat
- Research Technologies Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States
| | - Chengyu Liu
- Transgenic Core, National Heart, Lung, and Blood institutes, National Institutes of Health, Bethesda, MD, United States
| | - Jaspal S. Khillan
- Mouse Genetics and Gene Modification Section, Comparative Medicine Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States
| | - Jinfang Zhu
- Molecular and Cellular Immunoregulation Section, Laboratory of Immune System Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States
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Chen X, Zhao T, Ke N, Qian Y, Wang W, Liu L, Liu C. In-vitro differentiation of human embryonic stem cells into spinal cord neural stem cells. Neuroreport 2022; 33:518-525. [PMID: 35882016 DOI: 10.1097/wnr.0000000000001812] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
In-vitro differentiation of human embryonic stem cells into spinal cord neural stem cells (NSCs) can help researchers better understand the cellular processes associated with spinal cord development and regeneration, and provide therapeutic strategies for spinal cord disorders. However, effective and consistent methods for the generation of human spinal cord NSCs are rare. Objective of the study is to establish methods for the in-vitro induction and long-term maintenance of human spinal cord NSCs. H9 cells were treated with neural induction medium for 10 days under single-cell seeding condition, followed by treatment with neural maintenance medium and replacement with NSC medium after five passages. The identity of the generated cells was determined by immunofluorescence, immunoblotting, and cleavage under targets and tagmentation (CUT&Tag) assays. After the neural induction, OCT4, an embryonic stem cell marker, was significantly reduced, whereas NESTIN and PAX6, two NSC markers, were clearly increased. After the neural maintenance, most of the H9-derived cells consistently expressed NESTIN and PAX6 together with SOX1 and HOXC9, two spinal cord markers. The Homer known motif enrichment results of the CUT&Tag assay confirmed the expression of HOXC9 in the H9-derived spinal cord NSCs, which can be maintained for more than 40 days under an in vitro culture system. This study sheds new light on effective induction and maintenance of human spinal cord NSCs.
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Affiliation(s)
- Xueying Chen
- School of Basic Medical Sciences, Anhui Medical University
- Department of Histology and Embryology, Institute of Stem Cell and Tissue Engineering, Anhui Medical University
| | - Tianyi Zhao
- School of Basic Medical Sciences, Anhui Medical University
- Department of Histology and Embryology, Institute of Stem Cell and Tissue Engineering, Anhui Medical University
| | - Naiyu Ke
- The First Clinical Medical College, Anhui Medical University
| | - Yutong Qian
- The First Clinical Medical College, Anhui Medical University
| | - Wanrong Wang
- The First Clinical Medical College, Anhui Medical University
| | - Lihua Liu
- Institute of Clinical Pharmacology, Anhui Medical University, Hefei, China
| | - Chao Liu
- School of Basic Medical Sciences, Anhui Medical University
- Department of Histology and Embryology, Institute of Stem Cell and Tissue Engineering, Anhui Medical University
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11
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Pandey K, Zafar H. Inference of cell state transitions and cell fate plasticity from single-cell with MARGARET. Nucleic Acids Res 2022; 50:e86. [PMID: 35639499 PMCID: PMC9410915 DOI: 10.1093/nar/gkac412] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Revised: 04/27/2022] [Accepted: 05/17/2022] [Indexed: 11/27/2022] Open
Abstract
Despite recent advances in inferring cellular dynamics using single-cell RNA-seq data, existing trajectory inference (TI) methods face difficulty in accurately reconstructing the cell-state manifold and cell-fate plasticity for complex topologies. Here, we present MARGARET (https://github.com/Zafar-Lab/Margaret) for inferring single-cell trajectory and fate mapping for diverse dynamic cellular processes. MARGARET reconstructs complex trajectory topologies using a deep unsupervised metric learning and a graph-partitioning approach based on a novel connectivity measure, automatically detects terminal cell states, and generalizes the quantification of fate plasticity for complex topologies. On a diverse benchmark consisting of synthetic and real datasets, MARGARET outperformed state-of-the-art methods in recovering global topology and cell pseudotime ordering. For human hematopoiesis, MARGARET accurately identified all major lineages and associated gene expression trends and helped identify transitional progenitors associated with key branching events. For embryoid body differentiation, MARGARET identified novel transitional populations that were validated by bulk sequencing and functionally characterized different precursor populations in the mesoderm lineage. For colon differentiation, MARGARET characterized the lineage for BEST4/OTOP2 cells and the heterogeneity in goblet cell lineage in the colon under normal and inflamed ulcerative colitis conditions. Finally, we demonstrated that MARGARET can scale to large scRNA-seq datasets consisting of ∼ millions of cells.
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Affiliation(s)
- Kushagra Pandey
- Department of Computer Science and Engineering, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Hamim Zafar
- Department of Computer Science and Engineering, Indian Institute of Technology Kanpur, Kanpur 208016, India.,Department of Biological Sciences and Bioengineering, Indian Institute of Technology Kanpur, Kanpur 208016, India.,Mehta Family Centre for Engineering in Medicine, Indian Institute of Technology Kanpur, Kanpur 208016, India
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12
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Mukaigasa K, Sakuma C, Yaginuma H. The developmental hourglass model is applicable to the spinal cord based on single-cell transcriptomes and non-conserved cis-regulatory elements. Dev Growth Differ 2021; 63:372-391. [PMID: 34473348 PMCID: PMC9293469 DOI: 10.1111/dgd.12750] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 08/24/2021] [Accepted: 08/26/2021] [Indexed: 11/27/2022]
Abstract
The developmental hourglass model predicts that embryonic morphology is most conserved at the mid-embryonic stage and diverges at the early and late stages. To date, this model has been verified by examining the anatomical features or gene expression profiles at the whole embryonic level. Here, by data mining approach utilizing multiple genomic and transcriptomic datasets from different species in combination, and by experimental validation, we demonstrate that the hourglass model is also applicable to a reduced element, the spinal cord. In the middle of spinal cord development, dorsoventrally arrayed neuronal progenitor domains are established, which are conserved among vertebrates. By comparing the publicly available single-cell transcriptome datasets of mice and zebrafish, we found that ventral subpopulations of post-mitotic spinal neurons display divergent molecular profiles. We also detected the non-conservation of cis-regulatory elements located around the progenitor fate determinants, indicating that the cis-regulatory elements contributing to the progenitor specification are evolvable. These results demonstrate that, despite the conservation of the progenitor domains, the processes before and after the progenitor domain specification diverged. This study will be helpful to understand the molecular basis of the developmental hourglass model.
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Affiliation(s)
- Katsuki Mukaigasa
- Department of Neuroanatomy and EmbryologySchool of MedicineFukushima Medical UniversityFukushimaJapan
| | - Chie Sakuma
- Department of Neuroanatomy and EmbryologySchool of MedicineFukushima Medical UniversityFukushimaJapan
| | - Hiroyuki Yaginuma
- Department of Neuroanatomy and EmbryologySchool of MedicineFukushima Medical UniversityFukushimaJapan
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13
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Deryckere A, Styfhals R, Elagoz AM, Maes GE, Seuntjens E. Identification of neural progenitor cells and their progeny reveals long distance migration in the developing octopus brain. eLife 2021; 10:e69161. [PMID: 34425939 PMCID: PMC8384421 DOI: 10.7554/elife.69161] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Accepted: 07/21/2021] [Indexed: 12/28/2022] Open
Abstract
Cephalopods have evolved nervous systems that parallel the complexity of mammalian brains in terms of neuronal numbers and richness in behavioral output. How the cephalopod brain develops has only been described at the morphological level, and it remains unclear where the progenitor cells are located and what molecular factors drive neurogenesis. Using histological techniques, we located dividing cells, neural progenitors and postmitotic neurons in Octopus vulgaris embryos. Our results indicate that an important pool of progenitors, expressing the conserved bHLH transcription factors achaete-scute or neurogenin, is located outside the central brain cords in the lateral lips adjacent to the eyes, suggesting that newly formed neurons migrate into the cords. Lineage-tracing experiments then showed that progenitors, depending on their location in the lateral lips, generate neurons for the different lobes, similar to the squid Doryteuthis pealeii. The finding that octopus newborn neurons migrate over long distances is reminiscent of vertebrate neurogenesis and suggests it might be a fundamental strategy for large brain development.
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Affiliation(s)
- Astrid Deryckere
- Laboratory of Developmental Neurobiology, Department of Biology, KU LeuvenLeuvenBelgium
| | - Ruth Styfhals
- Laboratory of Developmental Neurobiology, Department of Biology, KU LeuvenLeuvenBelgium
- Department of Biology and Evolution of Marine Organisms, Stazione Zoologica Anton DohrnNaplesItaly
| | - Ali Murat Elagoz
- Laboratory of Developmental Neurobiology, Department of Biology, KU LeuvenLeuvenBelgium
| | - Gregory E Maes
- Center for Human Genetics, Genomics Core, UZ-KU LeuvenLeuvenBelgium
- Centre for Sustainable Tropical Fisheries and Aquaculture, College of Science and Engineering, James Cook UniversityTownsvilleAustralia
- Laboratory of Biodiversity and Evolutionary Genomics, Department of Biology, KU LeuvenLeuvenBelgium
| | - Eve Seuntjens
- Laboratory of Developmental Neurobiology, Department of Biology, KU LeuvenLeuvenBelgium
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14
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Baudouin C, Pelosi B, Courtoy GE, Achouri Y, Clotman F. Generation and characterization of a tamoxifen-inducible Vsx1-CreER T2 line to target V2 interneurons in the mouse developing spinal cord. Genesis 2021; 59:e23435. [PMID: 34080769 DOI: 10.1002/dvg.23435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 05/12/2021] [Accepted: 05/12/2021] [Indexed: 11/11/2022]
Abstract
In the spinal cord, ventral interneurons regulate the activity of motor neurons, thereby controlling motor activities including locomotion. Interneurons arise during embryonic development from distinct progenitor domains orderly distributed along the dorso-ventral axis of the neural tube. The p2 progenitor domain generates at least five V2 interneuron populations. However, identification and characterization of all V2 populations remain currently incomplete and the mechanisms that control their development remain only partly understood. In this study, we report the generation of a Vsx1-CreERT2 BAC transgenic mouse line that drives CreERT2 recombinase expression mimicking endogenous Vsx1 expression pattern in the developing spinal cord. We showed that the Vsx1-CreERT2 transgene can mediate recombination in V2 precursors with a high efficacy and specificity. Lineage tracing demonstrated that all the V2 interneurons in the mouse developing spinal cord derive from cells expressing Vsx1. Finally, we confirmed that V2 precursors generate additional V2 populations that are not characterized yet. Thus, the Vsx1-CreERT2 line described here is a useful genetic tool for lineage tracing and for functional studies of the mouse spinal V2 interneurons.
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Affiliation(s)
- Charlotte Baudouin
- Institute of Neuroscience, Université catholique de Louvain, Brussels, Belgium
| | - Barbara Pelosi
- Institute of Neuroscience, Université catholique de Louvain, Brussels, Belgium
| | - Guillaume E Courtoy
- Institut de Recherche Expérimentale et Clinique (IREC), Université catholique de Louvain, Brussels, Belgium
| | - Younes Achouri
- de Duve Institute, Transgenic Core Facility, Université catholique de Louvain, Brussels, Belgium
| | - Frédéric Clotman
- Institute of Neuroscience, Université catholique de Louvain, Brussels, Belgium
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15
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Yang L, Wang F, Strähle U. The Genetic Programs Specifying Kolmer-Agduhr Interneurons. Front Neurosci 2020; 14:577879. [PMID: 33162880 PMCID: PMC7581942 DOI: 10.3389/fnins.2020.577879] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 09/15/2020] [Indexed: 01/21/2023] Open
Abstract
Kolmer-Agduhr (KA) cells are a subgroup of interneurons positioned adjacent to the neurocoele with cilia on the apical surface protruding into the central canal of the spinal cord. Although KA cells were identified almost a century ago, their development and functions are only beginning to be unfolded. Recent studies have revealed the characteristics of KA cells in greater detail, including their spatial distribution, the timing of their differentiation, and their specification via extrinsic signaling and a unique combination of transcription factors in zebrafish and mouse. Cell lineage-tracing experiments have demonstrated that two subsets of KA cells, named KA' and KA" cells, differentiate from motoneuronal progenitors and floor-plate precursors, respectively, in both zebrafish and mouse. Although KA' and KA" cells originate from different progenitors/precursors, they each share a common set of transcription factors. Intriguingly, the combination of transcription factors that promote the acquisition of KA' cell characteristics differs from those that promote a KA" cell identity. In addition, KA' and KA" cells exhibit separable neuronal targets and differential responses to bending of the spinal cord. In this review, we summarize what is currently known about the genetic programs defining the identities of KA' and KA" cell identities. We then discuss how these two subgroups of KA cells are genetically specified.
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Affiliation(s)
- Lixin Yang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, China.,Center for Global Health, School of Public Health, Nanjing Medical University, Nanjing, China
| | - Feifei Wang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, China
| | - Uwe Strähle
- Institute of Biological and Chemical Systems - Biological Information Processing, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
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16
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Debrulle S, Baudouin C, Hidalgo-Figueroa M, Pelosi B, Francius C, Rucchin V, Ronellenfitch K, Chow RL, Tissir F, Lee SK, Clotman F. Vsx1 and Chx10 paralogs sequentially secure V2 interneuron identity during spinal cord development. Cell Mol Life Sci 2020; 77:4117-4131. [PMID: 31822965 PMCID: PMC11104857 DOI: 10.1007/s00018-019-03408-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Revised: 11/28/2019] [Accepted: 11/28/2019] [Indexed: 12/01/2022]
Abstract
Paralog factors are usually described as consolidating biological systems by displaying redundant functionality in the same cells. Here, we report that paralogs can also cooperate in distinct cell populations at successive stages of differentiation. In mouse embryonic spinal cord, motor neurons and V2 interneurons differentiate from adjacent progenitor domains that share identical developmental determinants. Therefore, additional strategies secure respective cell fate. In particular, Hb9 promotes motor neuron identity while inhibiting V2 differentiation, whereas Chx10 stimulates V2a differentiation while repressing motor neuron fate. However, Chx10 is not present at the onset of V2 differentiation and in other V2 populations. In the present study, we show that Vsx1, the single paralog of Chx10, which is produced earlier than Chx10 in V2 precursors, can inhibit motor neuron differentiation and promote V2 interneuron production. However, the single absence of Vsx1 does not impact on V2 fate consolidation, suggesting that lack of Vsx1 may be compensated by other factors. Nevertheless, Vsx1 cooperates with Chx10 to prevent motor neuron differentiation in early V2 precursors although these two paralog factors are not produced in the same cells. Hence, this study uncovers an original situation, namely labor division, wherein paralog genes cooperate at successive steps of neuronal development.
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Affiliation(s)
- Stéphanie Debrulle
- Université Catholique de Louvain, Institute of Neuroscience, Brussels, Belgium
| | - Charlotte Baudouin
- Université Catholique de Louvain, Institute of Neuroscience, Brussels, Belgium
| | - Maria Hidalgo-Figueroa
- Université Catholique de Louvain, Institute of Neuroscience, Brussels, Belgium
- Neuropsychopharmacology and Psychobiology Research Group, Area of Psychobiology, Department of Psychology, Instituto de Investigación E Innovación en Ciencias Biomédicas de Cádiz (INiBICA), University of Cadiz, Cadiz, Spain
| | - Barbara Pelosi
- Université Catholique de Louvain, Institute of Neuroscience, Brussels, Belgium
| | - Cédric Francius
- Université Catholique de Louvain, Institute of Neuroscience, Brussels, Belgium
- PAREXEL International, Paris, France
| | - Vincent Rucchin
- Université Catholique de Louvain, Institute of Neuroscience, Brussels, Belgium
| | | | - Robert L Chow
- Department of Biology, University of Victoria, Victoria, Canada
| | - Fadel Tissir
- Université Catholique de Louvain, Institute of Neuroscience, Brussels, Belgium
| | - Soo-Kyung Lee
- Oregon Health and Science University, Papé Family Pediatric Research Institute and Vollum Institute, Portland, USA
| | - Frédéric Clotman
- Université Catholique de Louvain, Institute of Neuroscience, Brussels, Belgium.
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17
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Sur A, Renfro A, Bergmann PJ, Meyer NP. Investigating cellular and molecular mechanisms of neurogenesis in Capitella teleta sheds light on the ancestor of Annelida. BMC Evol Biol 2020; 20:84. [PMID: 32664907 PMCID: PMC7362552 DOI: 10.1186/s12862-020-01636-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Accepted: 06/03/2020] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Diverse architectures of nervous systems (NSs) such as a plexus in cnidarians or a more centralized nervous system (CNS) in insects and vertebrates are present across Metazoa, but it is unclear what selection pressures drove evolution and diversification of NSs. One underlying aspect of this diversity lies in the cellular and molecular mechanisms driving neurogenesis, i.e. generation of neurons from neural precursor cells (NPCs). In cnidarians, vertebrates, and arthropods, homologs of SoxB and bHLH proneural genes control different steps of neurogenesis, suggesting that some neurogenic mechanisms may be conserved. However, data are lacking for spiralian taxa. RESULTS To that end, we characterized NPCs and their daughters at different stages of neurogenesis in the spiralian annelid Capitella teleta. We assessed cellular division patterns in the neuroectoderm using static and pulse-chase labeling with thymidine analogs (EdU and BrdU), which enabled identification of NPCs that underwent multiple rounds of division. Actively-dividing brain NPCs were found to be apically-localized, whereas actively-dividing NPCs for the ventral nerve cord (VNC) were found apically, basally, and closer to the ventral midline. We used lineage tracing to characterize the changing boundary of the trunk neuroectoderm. Finally, to start to generate a genetic hierarchy, we performed double-fluorescent in-situ hybridization (FISH) and single-FISH plus EdU labeling for neurogenic gene homologs. In the brain and VNC, Ct-soxB1 and Ct-neurogenin were expressed in a large proportion of apically-localized, EdU+ NPCs. In contrast, Ct-ash1 was expressed in a small subset of apically-localized, EdU+ NPCs and subsurface, EdU- cells, but not in Ct-neuroD+ or Ct-elav1+ cells, which also were subsurface. CONCLUSIONS Our data suggest a putative genetic hierarchy with Ct-soxB1 and Ct-neurogenin at the top, followed by Ct-ash1, then Ct-neuroD, and finally Ct-elav1. Comparison of our data with that from Platynereis dumerilii revealed expression of neurogenin homologs in proliferating NPCs in annelids, which appears different than the expression of vertebrate neurogenin homologs in cells that are exiting the cell cycle. Furthermore, differences between neurogenesis in the head versus trunk of C. teleta suggest that these two tissues may be independent developmental modules, possibly with differing evolutionary trajectories.
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Affiliation(s)
- A. Sur
- Department of Biology, Clark University, 950 Main Street, Worcester, MA 01610 USA
| | - A. Renfro
- Department of Biology, Clark University, 950 Main Street, Worcester, MA 01610 USA
| | - P. J. Bergmann
- Department of Biology, Clark University, 950 Main Street, Worcester, MA 01610 USA
| | - N. P. Meyer
- Department of Biology, Clark University, 950 Main Street, Worcester, MA 01610 USA
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18
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V2a interneuron differentiation from mouse and human pluripotent stem cells. Nat Protoc 2019; 14:3033-3058. [PMID: 31628445 DOI: 10.1038/s41596-019-0203-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Accepted: 06/03/2019] [Indexed: 02/06/2023]
Abstract
V2a interneurons are located in the hindbrain and spinal cord, where they provide rhythmic input to major motor control centers. Many of the phenotypic properties and functions of excitatory V2a interneurons have yet to be fully defined. Definition of these properties could lead to novel regenerative therapies for traumatic injuries and drug targets for chronic degenerative diseases. Here we describe how to produce V2a interneurons from mouse and human pluripotent stem cells (PSCs), as well as strategies to characterize and mature the cells for further analysis. The described protocols are based on a sequence of small-molecule treatments that induce differentiation of PSCs into V2a interneurons. We also include a detailed description of how to phenotypically characterize, mature, and freeze the cells. The mouse and human protocols are similar in regard to the sequence of small molecules used but differ slightly in the concentrations and durations necessary for induction. With the protocols described, scientists can expect to obtain V2a interneurons with purities of ~75% (mouse) in 7 d and ~50% (human) in 20 d.
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19
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Callahan RA, Roberts R, Sengupta M, Kimura Y, Higashijima SI, Bagnall MW. Spinal V2b neurons reveal a role for ipsilateral inhibition in speed control. eLife 2019; 8:e47837. [PMID: 31355747 PMCID: PMC6701946 DOI: 10.7554/elife.47837] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2019] [Accepted: 07/26/2019] [Indexed: 12/22/2022] Open
Abstract
The spinal cord contains a diverse array of interneurons that govern motor output. Traditionally, models of spinal circuits have emphasized the role of inhibition in enforcing reciprocal alternation between left and right sides or flexors and extensors. However, recent work has shown that inhibition also increases coincident with excitation during contraction. Here, using larval zebrafish, we investigate the V2b (Gata3+) class of neurons, which contribute to flexor-extensor alternation but are otherwise poorly understood. Using newly generated transgenic lines we define two stable subclasses with distinct neurotransmitter and morphological properties. These V2b subclasses synapse directly onto motor neurons with differential targeting to speed-specific circuits. In vivo, optogenetic manipulation of V2b activity modulates locomotor frequency: suppressing V2b neurons elicits faster locomotion, whereas activating V2b neurons slows locomotion. We conclude that V2b neurons serve as a brake on axial motor circuits. Together, these results indicate a role for ipsilateral inhibition in speed control.
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Affiliation(s)
- Rebecca A Callahan
- Department of NeuroscienceWashington University School of MedicineSt LouisUnited States
| | - Richard Roberts
- Department of NeuroscienceWashington University School of MedicineSt LouisUnited States
| | - Mohini Sengupta
- Department of NeuroscienceWashington University School of MedicineSt LouisUnited States
| | | | | | - Martha W Bagnall
- Department of NeuroscienceWashington University School of MedicineSt LouisUnited States
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20
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Harris A, Masgutova G, Collin A, Toch M, Hidalgo-Figueroa M, Jacob B, Corcoran LM, Francius C, Clotman F. Onecut Factors and Pou2f2 Regulate the Distribution of V2 Interneurons in the Mouse Developing Spinal Cord. Front Cell Neurosci 2019; 13:184. [PMID: 31231191 PMCID: PMC6561314 DOI: 10.3389/fncel.2019.00184] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Accepted: 04/12/2019] [Indexed: 11/21/2022] Open
Abstract
Acquisition of proper neuronal identity and position is critical for the formation of neural circuits. In the embryonic spinal cord, cardinal populations of interneurons diversify into specialized subsets and migrate to defined locations within the spinal parenchyma. However, the factors that control interneuron diversification and migration remain poorly characterized. Here, we show that the Onecut transcription factors are necessary for proper diversification and distribution of the V2 interneurons in the developing spinal cord. Furthermore, we uncover that these proteins restrict and moderate the expression of spinal isoforms of Pou2f2, a transcription factor known to regulate B-cell differentiation. By gain- or loss-of-function experiments, we show that Pou2f2 contribute to regulate the position of V2 populations in the developing spinal cord. Thus, we uncovered a genetic pathway that regulates the diversification and the distribution of V2 interneurons during embryonic development.
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Affiliation(s)
- Audrey Harris
- Laboratory of Neural Differentiation, Institute of Neuroscience, Université catholique de Louvain, Brussels, Belgium
| | - Gauhar Masgutova
- Laboratory of Neural Differentiation, Institute of Neuroscience, Université catholique de Louvain, Brussels, Belgium
| | - Amandine Collin
- Laboratory of Neural Differentiation, Institute of Neuroscience, Université catholique de Louvain, Brussels, Belgium
| | - Mathilde Toch
- Laboratory of Neural Differentiation, Institute of Neuroscience, Université catholique de Louvain, Brussels, Belgium
| | - Maria Hidalgo-Figueroa
- Laboratory of Neural Differentiation, Institute of Neuroscience, Université catholique de Louvain, Brussels, Belgium
| | - Benvenuto Jacob
- Institute of Neuroscience, System and Cognition Division, Université catholique de Louvain, Brussels, Belgium
| | - Lynn M. Corcoran
- Molecular Immunology Division and Immunology Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
| | - Cédric Francius
- Laboratory of Neural Differentiation, Institute of Neuroscience, Université catholique de Louvain, Brussels, Belgium
| | - Frédéric Clotman
- Laboratory of Neural Differentiation, Institute of Neuroscience, Université catholique de Louvain, Brussels, Belgium
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21
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Gerber V, Yang L, Takamiya M, Ribes V, Gourain V, Peravali R, Stegmaier J, Mikut R, Reischl M, Ferg M, Rastegar S, Strähle U. The HMG box transcription factors Sox1a and b specify a new class of glycinergic interneurons in the spinal cord of zebrafish embryos. Development 2019; 146:dev.172510. [DOI: 10.1242/dev.172510] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2018] [Accepted: 01/30/2019] [Indexed: 12/17/2022]
Abstract
Specification of neurons in the spinal cord relies on extrinsic and intrinsic signals, which in turn are interpreted by expression of transcription factors. V2 interneurons develop from the ventral aspects of the spinal cord. We report here a novel neuronal V2 subtype, named V2s, in zebrafish embryos. Formation of these neurons depends on the transcription factors sox1a and sox1b. They develop from common gata2a/gata3 dependent precursors co-expressing markers of V2b and V2s interneurons. Chemical blockage of Notch signaling causes a decrease of V2s and an increase of V2b cells. Our results are consistent with the existence of at least two types of precursors arranged in a hierarchical manner in the V2 domain. V2s neurons grow long ipsilateral descending axonal projections with a short branch at the ventral midline. They acquire a glycinergic neurotransmitter type during the second day of development. Unilateral ablation of V2s interneurons causes a delay in touch-provoked escape behavior suggesting that V2s interneurons are involved in fast motor responses.
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Affiliation(s)
- Vanessa Gerber
- Institute of Toxicology and Genetics, Karlsruhe Institute of Technology (KIT), 76021 Karlsruhe, Germany
| | - Lixin Yang
- Institute of Toxicology and Genetics, Karlsruhe Institute of Technology (KIT), 76021 Karlsruhe, Germany
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, 100012, Beijing, China
| | - Masanari Takamiya
- Institute of Toxicology and Genetics, Karlsruhe Institute of Technology (KIT), 76021 Karlsruhe, Germany
| | - Vanessa Ribes
- Institute Jacques Monod, CNRS UMR7592, Université Paris Diderot, Sorbonne Paris Cité, 75205 Paris Cedex, France
| | - Victor Gourain
- Institute of Toxicology and Genetics, Karlsruhe Institute of Technology (KIT), 76021 Karlsruhe, Germany
| | - Ravindra Peravali
- Institute of Toxicology and Genetics, Karlsruhe Institute of Technology (KIT), 76021 Karlsruhe, Germany
| | - Johannes Stegmaier
- Institute for Automation and Applied Informatics, Karlsruhe Institute of Technology (KIT), 76021 Karlsruhe, Germany
- Institute of Imaging & Computer Vision, RWTH Aachen University, 52074 Aachen, Germany
| | - Ralf Mikut
- Institute for Automation and Applied Informatics, Karlsruhe Institute of Technology (KIT), 76021 Karlsruhe, Germany
| | - Markus Reischl
- Institute for Automation and Applied Informatics, Karlsruhe Institute of Technology (KIT), 76021 Karlsruhe, Germany
| | - Marco Ferg
- Institute of Toxicology and Genetics, Karlsruhe Institute of Technology (KIT), 76021 Karlsruhe, Germany
| | - Sepand Rastegar
- Institute of Toxicology and Genetics, Karlsruhe Institute of Technology (KIT), 76021 Karlsruhe, Germany
| | - Uwe Strähle
- Institute of Toxicology and Genetics, Karlsruhe Institute of Technology (KIT), 76021 Karlsruhe, Germany
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22
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Makrides N, Panayiotou E, Fanis P, Karaiskos C, Lapathitis G, Malas S. Sequential Role of SOXB2 Factors in GABAergic Neuron Specification of the Dorsal Midbrain. Front Mol Neurosci 2018; 11:152. [PMID: 29867344 PMCID: PMC5952183 DOI: 10.3389/fnmol.2018.00152] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Accepted: 04/17/2018] [Indexed: 12/23/2022] Open
Abstract
Studies proposed a model for embryonic neurogenesis where the expression levels of the SOXB2 and SOXB1 factors regulate the differentiation status of the neural stem cells. However, the precise role of the SOXB2 genes remains controversial. Therefore, this study aims to investigate the effects of individual deletions of the SOX21 and SOX14 genes during the development of the dorsal midbrain. We show that SOX21 and SOX14 function distinctly during the commitment of the GABAergic lineage. More explicitly, deletion of SOX21 reduced the expression of the GABAergic precursor marker GATA3 and BHLHB5 while the expression of GAD6, which marks GABAergic terminal differentiation, was not affected. In contrast deletion of SOX14 alone was sufficient to inhibit terminal differentiation of the dorsal midbrain GABAergic neurons. Furthermore, we demonstrate through gain-of-function experiments, that despite the homology of SOX21 and SOX14, they have unique gene targets and cannot compensate for the loss of each other. Taken together, these data do not support a pan-neurogenic function for SOXB2 genes in the dorsal midbrain, but instead they influence, sequentially, the specification of GABAergic neurons.
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Affiliation(s)
- Neoklis Makrides
- Developmental and Functional Genetics Group, The Cyprus Institute of Neurology & Genetics and Cyprus School of Molecular Medicine, Nicosia, Cyprus
| | - Elena Panayiotou
- Neurologic Clinic A, The Cyprus Institute of Neurology & Genetics, Nicosia, Cyprus
| | - Pavlos Fanis
- Department of Molecular Genetics, Function & Therapy, The Cyprus Institute of Neurology & Genetics, Nicosia, Cyprus
| | - Christos Karaiskos
- Neuroscience Laboratory, The Cyprus Institute of Neurology & Genetics, Nicosia, Cyprus
| | - George Lapathitis
- Neuroscience Laboratory, The Cyprus Institute of Neurology & Genetics, Nicosia, Cyprus
| | - Stavros Malas
- Developmental and Functional Genetics Group, The Cyprus Institute of Neurology & Genetics and Cyprus School of Molecular Medicine, Nicosia, Cyprus
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23
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Andrzejczuk LA, Banerjee S, England SJ, Voufo C, Kamara K, Lewis KE. Tal1, Gata2a, and Gata3 Have Distinct Functions in the Development of V2b and Cerebrospinal Fluid-Contacting KA Spinal Neurons. Front Neurosci 2018; 12:170. [PMID: 29651232 PMCID: PMC5884927 DOI: 10.3389/fnins.2018.00170] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Accepted: 03/02/2018] [Indexed: 12/17/2022] Open
Abstract
Vertebrate locomotor circuitry contains distinct classes of ventral spinal cord neurons which each have particular functional properties. While we know some of the genes expressed by each of these cell types, we do not yet know how several of these neurons are specified. Here, we investigate the functions of Tal1, Gata2a, and Gata3 transcription factors in the development of two of these populations of neurons with important roles in locomotor circuitry: V2b neurons and cerebrospinal fluid-contacting Kolmer-Agduhr (KA) neurons (also called CSF-cNs). Our data provide the first demonstration, in any vertebrate, that Tal1 and Gata3 are required for correct development of KA and V2b neurons, respectively. We also uncover differences in the genetic regulation of V2b cell development in zebrafish compared to mouse. In addition, we demonstrate that Sox1a and Sox1b are expressed by KA and V2b neurons in zebrafish, which differs from mouse, where Sox1 is expressed by V2c neurons. KA neurons can be divided into ventral KA″ neurons and more dorsal KA′ neurons. Consistent with previous morpholino experiments, our mutant data suggest that Tal1 and Gata3 are required in KA′ but not KA″ cells, whereas Gata2a is required in KA″ but not KA′ cells, even though both of these cell types co-express all three of these transcription factors. In gata2a mutants, cells in the KA″ region of the spinal cord lose expression of most KA″ genes and there is an increase in the number of cells expressing V3 genes, suggesting that Gata2a is required to specify KA″ and repress V3 fates in cells that normally develop into KA″ neurons. On the other hand, our data suggest that Gata3 and Tal1 are both required for KA′ neurons to differentiate from progenitor cells. In the KA′ region of these mutants, cells no longer express KA′ markers and there is an increase in the number of mitotically-active cells. Finally, our data demonstrate that all three of these transcription factors are required for later stages of V2b neuron differentiation and that Gata2a and Tal1 have different functions in V2b development in zebrafish than in mouse.
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Affiliation(s)
| | - Santanu Banerjee
- Department of Biology, Syracuse University, Syracuse, NY, United States
| | | | - Christiane Voufo
- Department of Biology, Syracuse University, Syracuse, NY, United States
| | - Kadiah Kamara
- Department of Biology, Syracuse University, Syracuse, NY, United States
| | - Katharine E Lewis
- Department of Biology, Syracuse University, Syracuse, NY, United States
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24
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Lai HC, Seal RP, Johnson JE. Making sense out of spinal cord somatosensory development. Development 2017; 143:3434-3448. [PMID: 27702783 DOI: 10.1242/dev.139592] [Citation(s) in RCA: 126] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The spinal cord integrates and relays somatosensory input, leading to complex motor responses. Research over the past couple of decades has identified transcription factor networks that function during development to define and instruct the generation of diverse neuronal populations within the spinal cord. A number of studies have now started to connect these developmentally defined populations with their roles in somatosensory circuits. Here, we review our current understanding of how neuronal diversity in the dorsal spinal cord is generated and we discuss the logic underlying how these neurons form the basis of somatosensory circuits.
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Affiliation(s)
- Helen C Lai
- Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Rebecca P Seal
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15260, USA
| | - Jane E Johnson
- Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
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25
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Kabayiza KU, Masgutova G, Harris A, Rucchin V, Jacob B, Clotman F. The Onecut Transcription Factors Regulate Differentiation and Distribution of Dorsal Interneurons during Spinal Cord Development. Front Mol Neurosci 2017; 10:157. [PMID: 28603487 PMCID: PMC5445119 DOI: 10.3389/fnmol.2017.00157] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Accepted: 05/08/2017] [Indexed: 01/09/2023] Open
Abstract
During embryonic development, the dorsal spinal cord generates numerous interneuron populations eventually involved in motor circuits or in sensory networks that integrate and transmit sensory inputs from the periphery. The molecular mechanisms that regulate the specification of these multiple dorsal neuronal populations have been extensively characterized. In contrast, the factors that contribute to their diversification into smaller specialized subsets and those that control the specific distribution of each population in the developing spinal cord remain unknown. Here, we demonstrate that the Onecut transcription factors, namely Hepatocyte Nuclear Factor-6 (HNF-6) (or OC-1), OC-2 and OC-3, regulate the diversification and the distribution of spinal dorsal interneuron (dINs). Onecut proteins are dynamically and differentially distributed in spinal dINs during differentiation and migration. Analyzes of mutant embryos devoid of Onecut factors in the developing spinal cord evidenced a requirement in Onecut proteins for proper production of a specific subset of dI5 interneurons. In addition, the distribution of dI3, dI5 and dI6 interneuron populations was altered. Hence, Onecut transcription factors control genetic programs that contribute to the regulation of spinal dIN diversification and distribution during embryonic development.
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Affiliation(s)
- Karolina U Kabayiza
- Université catholique de Louvain, Institute of Neuroscience, Laboratory of Neural DifferentiationBrussels, Belgium.,Biology Department, School of Science, College of Science and Technology, University of RwandaButare, Rwanda
| | - Gauhar Masgutova
- Université catholique de Louvain, Institute of Neuroscience, Laboratory of Neural DifferentiationBrussels, Belgium
| | - Audrey Harris
- Université catholique de Louvain, Institute of Neuroscience, Laboratory of Neural DifferentiationBrussels, Belgium
| | - Vincent Rucchin
- Université catholique de Louvain, Institute of Neuroscience, Laboratory of Neural DifferentiationBrussels, Belgium
| | - Benvenuto Jacob
- Université catholique de Louvain, Institute of Neuroscience, System and Cognition DivisionBrussels, Belgium
| | - Frédéric Clotman
- Université catholique de Louvain, Institute of Neuroscience, Laboratory of Neural DifferentiationBrussels, Belgium
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26
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Flynn JR, Conn VL, Boyle KA, Hughes DI, Watanabe M, Velasquez T, Goulding MD, Callister RJ, Graham BA. Anatomical and Molecular Properties of Long Descending Propriospinal Neurons in Mice. Front Neuroanat 2017; 11:5. [PMID: 28220062 PMCID: PMC5292581 DOI: 10.3389/fnana.2017.00005] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Accepted: 01/19/2017] [Indexed: 11/13/2022] Open
Abstract
Long descending propriospinal neurons (LDPNs) are interneurons that form direct connections between cervical and lumbar spinal circuits. LDPNs are involved in interlimb coordination and are important mediators of functional recovery after spinal cord injury (SCI). Much of what we know about LDPNs comes from a range of species, however, the increased use of transgenic mouse lines to better define neuronal populations calls for a more complete characterisation of LDPNs in mice. In this study, we examined the cell body location, inhibitory neurotransmitter phenotype, developmental provenance, morphology and synaptic inputs of mouse LDPNs throughout the cervical and upper thoracic spinal cord. LDPNs were retrogradely labelled from the lumbar spinal cord to map cell body locations throughout the cervical and upper thoracic segments. Ipsilateral LDPNs were distributed throughout the dorsal, intermediate and ventral grey matter as well as the lateral spinal nucleus and lateral cervical nucleus. In contrast, contralateral LDPNs were more densely concentrated in the ventromedial grey matter. Retrograde labelling in GlyT2GFP and GAD67GFP mice showed the majority of inhibitory LDPNs project either ipsilaterally or adjacent to the midline. Additionally, we used several transgenic mouse lines to define the developmental provenance of LDPNs and found that V2b positive neurons form a subset of ipsilaterally projecting LDPNs. Finally, a population of Neurobiotin (NB) labelled LDPNs were assessed in detail to examine morphology and plot the spatial distribution of contacts from a variety of neurochemically distinct axon terminals. These results provide important baseline data in mice for future work on their role in locomotion and recovery from SCI.
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Affiliation(s)
- Jamie R Flynn
- School of Biomedical Sciences and Pharmacy, University of NewcastleCallaghan, NSW, Australia; Hunter Medical Research InstituteNewcastle, NSW, Australia
| | - Victoria L Conn
- Institute of Neuroscience and Psychology, University of Glasgow Glasgow, UK
| | - Kieran A Boyle
- Institute of Neuroscience and Psychology, University of Glasgow Glasgow, UK
| | - David I Hughes
- Institute of Neuroscience and Psychology, University of Glasgow Glasgow, UK
| | - Masahiko Watanabe
- Department of Anatomy, Hokkaido University School of Medicine Sapporo, Japan
| | - Tomoko Velasquez
- Molecular Neurobiology Laboratory, The Salk Institute for Biological Studies La Jolla, CA, USA
| | - Martyn D Goulding
- Molecular Neurobiology Laboratory, The Salk Institute for Biological Studies La Jolla, CA, USA
| | - Robert J Callister
- School of Biomedical Sciences and Pharmacy, University of NewcastleCallaghan, NSW, Australia; Hunter Medical Research InstituteNewcastle, NSW, Australia
| | - Brett A Graham
- School of Biomedical Sciences and Pharmacy, University of NewcastleCallaghan, NSW, Australia; Hunter Medical Research InstituteNewcastle, NSW, Australia
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27
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Francius C, Hidalgo-Figueroa M, Debrulle S, Pelosi B, Rucchin V, Ronellenfitch K, Panayiotou E, Makrides N, Misra K, Harris A, Hassani H, Schakman O, Parras C, Xiang M, Malas S, Chow RL, Clotman F. Vsx1 Transiently Defines an Early Intermediate V2 Interneuron Precursor Compartment in the Mouse Developing Spinal Cord. Front Mol Neurosci 2016; 9:145. [PMID: 28082864 PMCID: PMC5183629 DOI: 10.3389/fnmol.2016.00145] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2016] [Accepted: 11/30/2016] [Indexed: 12/30/2022] Open
Abstract
Spinal ventral interneurons regulate the activity of motor neurons, thereby controlling motor activities. Interneurons arise during embryonic development from distinct progenitor domains distributed orderly along the dorso-ventral axis of the neural tube. A single ventral progenitor population named p2 generates at least five V2 interneuron subsets. Whether the diversification of V2 precursors into multiple subsets occurs within the p2 progenitor domain or involves a later compartment of early-born V2 interneurons remains unsolved. Here, we provide evidence that the p2 domain produces an intermediate V2 precursor compartment characterized by the transient expression of the transcriptional repressor Vsx1. These cells display an original repertoire of cellular markers distinct from that of any V2 interneuron population. They have exited the cell cycle but have not initiated neuronal differentiation. They coexpress Vsx1 and Foxn4, suggesting that they can generate the known V2 interneuron populations as well as possible additional V2 subsets. Unlike V2 interneurons, the generation of Vsx1-positive precursors does not depend on the Notch signaling pathway but expression of Vsx1 in these cells requires Pax6. Hence, the p2 progenitor domain generates an intermediate V2 precursor compartment, characterized by the presence of the transcriptional repressor Vsx1, that contributes to V2 interneuron development.
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Affiliation(s)
- Cédric Francius
- Laboratory of Neural Differentiation, Institute of Neuroscience, Université catholique de LouvainBrussels, Belgium
| | - María Hidalgo-Figueroa
- Laboratory of Neural Differentiation, Institute of Neuroscience, Université catholique de LouvainBrussels, Belgium
| | - Stéphanie Debrulle
- Laboratory of Neural Differentiation, Institute of Neuroscience, Université catholique de LouvainBrussels, Belgium
| | - Barbara Pelosi
- Laboratory of Neural Differentiation, Institute of Neuroscience, Université catholique de LouvainBrussels, Belgium
| | - Vincent Rucchin
- Laboratory of Neural Differentiation, Institute of Neuroscience, Université catholique de LouvainBrussels, Belgium
| | | | | | | | - Kamana Misra
- Center for Advanced Biotechnology and Medicine and Department of Pediatrics, Rutgers University - Robert Wood Johnson Medical SchoolPiscataway, NJ, USA
| | - Audrey Harris
- Laboratory of Neural Differentiation, Institute of Neuroscience, Université catholique de LouvainBrussels, Belgium
| | - Hessameh Hassani
- Inserm U 1127, CNRS UMR 7225, Sorbonne Universités, UPMC University Paris 06 UMR S 1127, Institut du Cerveau et de la Moelle épinière (ICM)Paris, France
| | - Olivier Schakman
- Laboratory of Cell Physiology, Institute of Neuroscience, Université catholique de LouvainBrussels, Belgium
| | - Carlos Parras
- Inserm U 1127, CNRS UMR 7225, Sorbonne Universités, UPMC University Paris 06 UMR S 1127, Institut du Cerveau et de la Moelle épinière (ICM)Paris, France
| | - Mengqing Xiang
- Center for Advanced Biotechnology and Medicine and Department of Pediatrics, Rutgers University - Robert Wood Johnson Medical SchoolPiscataway, NJ, USA
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen UniversityGuangzhou, China
| | - Stavros Malas
- The Cyprus Institute of Neurology and GeneticsNicosia, Cyprus
| | - Robert L. Chow
- Department of Biology, University of VictoriaVictoria, BC, Canada
| | - Frédéric Clotman
- Laboratory of Neural Differentiation, Institute of Neuroscience, Université catholique de LouvainBrussels, Belgium
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28
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Mandalos NP, Remboutsika E. Sox2: To crest or not to crest? Semin Cell Dev Biol 2016; 63:43-49. [PMID: 27592260 DOI: 10.1016/j.semcdb.2016.08.035] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Revised: 08/29/2016] [Accepted: 08/30/2016] [Indexed: 12/12/2022]
Abstract
Precise control of neural progenitor transformation into neural crest stem cells ensures proper craniofacial and head development. In the neural progenitor pool, SoxB factors play an essential role as cell fate determinants of neural development, whereas during neural crest stem cell formation, Sox2 plays a predominant role as a guardian of the developmental clock that ensures precision of cell flow in the developing head.
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Affiliation(s)
- Nikolaos Panagiotis Mandalos
- National University of Athens Medical School, Department of Pediatrics, 75 Mikras Asias Str., 115 27, Athens, Greece; Stem Cell Biology Laboratory, Biomedical Sciences Research Centre "Alexander Fleming", 34 Fleming Str., 16672 Vari-Attica, Greece; Adjunct Faculty, The Lieber Institute for Brain Development, Basic Sciences Division, Johns Hopkins Medical Campus, 855 North Wolfe Str., Suite 300, 3rd Floor, Baltimore, MD 21205, USA
| | - Eumorphia Remboutsika
- National University of Athens Medical School, Department of Pediatrics, 75 Mikras Asias Str., 115 27, Athens, Greece; Stem Cell Biology Laboratory, Biomedical Sciences Research Centre "Alexander Fleming", 34 Fleming Str., 16672 Vari-Attica, Greece; Adjunct Faculty, The Lieber Institute for Brain Development, Basic Sciences Division, Johns Hopkins Medical Campus, 855 North Wolfe Str., Suite 300, 3rd Floor, Baltimore, MD 21205, USA.
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29
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Petracca YL, Sartoretti MM, Di Bella DJ, Marin-Burgin A, Carcagno AL, Schinder AF, Lanuza GM. The late and dual origin of cerebrospinal fluid-contacting neurons in the mouse spinal cord. Development 2016; 143:880-91. [PMID: 26839365 DOI: 10.1242/dev.129254] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Accepted: 01/25/2016] [Indexed: 12/16/2022]
Abstract
Considerable progress has been made in understanding the mechanisms that control the production of specialized neuronal types. However, how the timing of differentiation contributes to neuronal diversity in the developing spinal cord is still a pending question. In this study, we show that cerebrospinal fluid-contacting neurons (CSF-cNs), an anatomically discrete cell type of the ependymal area, originate from surprisingly late neurogenic events in the ventral spinal cord. CSF-cNs are identified by the expression of the transcription factors Gata2 and Gata3, and the ionic channels Pkd2l1 and Pkd1l2. Contrasting with Gata2/3(+) V2b interneurons, differentiation of CSF-cNs is independent of Foxn4 and takes place during advanced developmental stages previously assumed to be exclusively gliogenic. CSF-cNs are produced from two distinct dorsoventral regions of the mouse spinal cord. Most CSF-cNs derive from progenitors circumscribed to the late-p2 and the oligodendrogenic (pOL) domains, whereas a second subset of CSF-cNs arises from cells bordering the floor plate. The development of these two subgroups of CSF-cNs is differentially controlled by Pax6, they adopt separate locations around the postnatal central canal and they display electrophysiological differences. Our results highlight that spatiotemporal mechanisms are instrumental in creating neural cell diversity in the ventral spinal cord to produce distinct classes of interneurons, motoneurons, CSF-cNs, glial cells and ependymal cells.
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Affiliation(s)
- Yanina L Petracca
- Developmental Neurobiology Lab, Instituto Leloir and Consejo Nacional de Investigaciones Científicas y Técnicas (IIBBA-CONICET), Avenida Patricias Argentinas 435, Buenos Aires 1405, Argentina
| | - Maria Micaela Sartoretti
- Developmental Neurobiology Lab, Instituto Leloir and Consejo Nacional de Investigaciones Científicas y Técnicas (IIBBA-CONICET), Avenida Patricias Argentinas 435, Buenos Aires 1405, Argentina
| | - Daniela J Di Bella
- Developmental Neurobiology Lab, Instituto Leloir and Consejo Nacional de Investigaciones Científicas y Técnicas (IIBBA-CONICET), Avenida Patricias Argentinas 435, Buenos Aires 1405, Argentina
| | - Antonia Marin-Burgin
- Neuronal Plasticity Lab, Instituto Leloir and Consejo Nacional de Investigaciones Científicas y Técnicas (IIBBA-CONICET), Avenida Patricias Argentinas 435, Buenos Aires 1405, Argentina
| | - Abel L Carcagno
- Developmental Neurobiology Lab, Instituto Leloir and Consejo Nacional de Investigaciones Científicas y Técnicas (IIBBA-CONICET), Avenida Patricias Argentinas 435, Buenos Aires 1405, Argentina
| | - Alejandro F Schinder
- Neuronal Plasticity Lab, Instituto Leloir and Consejo Nacional de Investigaciones Científicas y Técnicas (IIBBA-CONICET), Avenida Patricias Argentinas 435, Buenos Aires 1405, Argentina
| | - Guillermo M Lanuza
- Developmental Neurobiology Lab, Instituto Leloir and Consejo Nacional de Investigaciones Científicas y Técnicas (IIBBA-CONICET), Avenida Patricias Argentinas 435, Buenos Aires 1405, Argentina
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30
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Bui TV, Stifani N, Panek I, Farah C. Genetically identified spinal interneurons integrating tactile afferents for motor control. J Neurophysiol 2015; 114:3050-63. [PMID: 26445867 DOI: 10.1152/jn.00522.2015] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Accepted: 09/28/2015] [Indexed: 11/22/2022] Open
Abstract
Our movements are shaped by our perception of the world as communicated by our senses. Perception of sensory information has been largely attributed to cortical activity. However, a prior level of sensory processing occurs in the spinal cord. Indeed, sensory inputs directly project to many spinal circuits, some of which communicate with motor circuits within the spinal cord. Therefore, the processing of sensory information for the purpose of ensuring proper movements is distributed between spinal and supraspinal circuits. The mechanisms underlying the integration of sensory information for motor control at the level of the spinal cord have yet to be fully described. Recent research has led to the characterization of spinal neuron populations that share common molecular identities. Identification of molecular markers that define specific populations of spinal neurons is a prerequisite to the application of genetic techniques devised to both delineate the function of these spinal neurons and their connectivity. This strategy has been used in the study of spinal neurons that receive tactile inputs from sensory neurons innervating the skin. As a result, the circuits that include these spinal neurons have been revealed to play important roles in specific aspects of motor function. We describe these genetically identified spinal neurons that integrate tactile information and the contribution of these studies to our understanding of how tactile information shapes motor output. Furthermore, we describe future opportunities that these circuits present for shedding light on the neural mechanisms of tactile processing.
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Affiliation(s)
- Tuan V Bui
- Department of Biology, University of Ottawa, Ottawa, Ontario, Canada; Center for Neural Dynamics, University of Ottawa, Ottawa, Ontario, Canada; and
| | - Nicolas Stifani
- Department of Medical Neuroscience, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Izabela Panek
- Department of Medical Neuroscience, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Carl Farah
- Department of Biology, University of Ottawa, Ottawa, Ontario, Canada
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31
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Abstract
Control of movement is a fundamental and complex task of the vertebrate nervous system, which relies on communication between circuits distributed throughout the brain and spinal cord. Many of the networks essential for the execution of basic locomotor behaviors are composed of discrete neuronal populations residing within the spinal cord. The organization and connectivity of these circuits is established through programs that generate functionally diverse neuronal subtypes, each contributing to a specific facet of motor output. Significant progress has been made in deciphering how neuronal subtypes are specified and in delineating the guidance and synaptic specificity determinants at the core of motor circuit assembly. Recent studies have shed light on the basic principles linking locomotor circuit connectivity with function, and they are beginning to reveal how more sophisticated motor behaviors are encoded. In this review, we discuss the impact of developmental programs in specifying motor behaviors governed by spinal circuits.
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Affiliation(s)
- Catarina Catela
- Neuroscience Institute and Department of Neuroscience and Physiology, New York University School of Medicine, New York, NY 10016;
| | - Maggie M Shin
- Neuroscience Institute and Department of Neuroscience and Physiology, New York University School of Medicine, New York, NY 10016;
| | - Jeremy S Dasen
- Neuroscience Institute and Department of Neuroscience and Physiology, New York University School of Medicine, New York, NY 10016;
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32
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Vidal B, Santella A, Serrano-Saiz E, Bao Z, Chuang CF, Hobert O. C. elegans SoxB genes are dispensable for embryonic neurogenesis but required for terminal differentiation of specific neuron types. Development 2015; 142:2464-77. [PMID: 26153233 DOI: 10.1242/dev.125740] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2015] [Accepted: 05/28/2015] [Indexed: 12/31/2022]
Abstract
Neurogenesis involves deeply conserved patterning molecules, such as the proneural basic helix-loop-helix transcription factors. Sox proteins and specifically members of the SoxB and SoxC groups are another class of conserved transcription factors with an important role in neuronal fate commitment and differentiation in various species. In this study, we examine the expression of all five Sox genes of the nematode C. elegans and analyze the effect of null mutant alleles of all members of the SoxB and SoxC groups on nervous system development. Surprisingly, we find that, unlike in other systems, neither of the two C. elegans SoxB genes sox-2 (SoxB1) and sox-3 (SoxB2), nor the sole C. elegans SoxC gene sem-2, is broadly expressed throughout the embryonic or adult nervous system and that all three genes are mostly dispensable for embryonic neurogenesis. Instead, sox-2 is required to maintain the developmental potential of blast cells that are generated in the embryo but divide only postembryonically to give rise to differentiated neuronal cell types. Moreover, sox-2 and sox-3 have selective roles in the terminal differentiation of specific neuronal cell types. Our findings suggest that the common themes of SoxB gene function across phylogeny lie in specifying developmental potential and, later on, in selectively controlling terminal differentiation programs of specific neuron types, but not in broadly controlling neurogenesis.
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Affiliation(s)
- Berta Vidal
- Department of Biochemistry and Molecular Biophysics, Howard Hughes Medical Institute, Columbia University Medical Center, New York, NY 10032, USA
| | - Anthony Santella
- Developmental Biology Program, Sloan-Kettering Institute, New York, NY 10065, USA
| | - Esther Serrano-Saiz
- Department of Biochemistry and Molecular Biophysics, Howard Hughes Medical Institute, Columbia University Medical Center, New York, NY 10032, USA
| | - Zhirong Bao
- Developmental Biology Program, Sloan-Kettering Institute, New York, NY 10065, USA
| | - Chiou-Fen Chuang
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, IL 60607, USA
| | - Oliver Hobert
- Department of Biochemistry and Molecular Biophysics, Howard Hughes Medical Institute, Columbia University Medical Center, New York, NY 10032, USA
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33
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Lu DC, Niu T, Alaynick WA. Molecular and cellular development of spinal cord locomotor circuitry. Front Mol Neurosci 2015; 8:25. [PMID: 26136656 PMCID: PMC4468382 DOI: 10.3389/fnmol.2015.00025] [Citation(s) in RCA: 142] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Accepted: 05/30/2015] [Indexed: 01/20/2023] Open
Abstract
The spinal cord of vertebrate animals is comprised of intrinsic circuits that are capable of sensing the environment and generating complex motor behaviors. There are two major perspectives for understanding the biology of this complicated structure. The first approaches the spinal cord from the point of view of function and is based on classic and ongoing research in electrophysiology, adult behavior, and spinal cord injury. The second view considers the spinal cord from a developmental perspective and is founded mostly on gene expression and gain-of-function and loss-of-function genetic experiments. Together these studies have uncovered functional classes of neurons and their lineage relationships. In this review, we summarize our knowledge of developmental classes, with an eye toward understanding the functional roles of each group.
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Affiliation(s)
- Daniel C Lu
- Department of Neurosurgery, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA USA
| | - Tianyi Niu
- Department of Neurosurgery, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA USA
| | - William A Alaynick
- Department of Neurosurgery, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA USA
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34
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Commissural axonal corridors instruct neuronal migration in the mouse spinal cord. Nat Commun 2015; 6:7028. [DOI: 10.1038/ncomms8028] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Accepted: 03/25/2015] [Indexed: 12/24/2022] Open
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35
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Wainger BJ, Buttermore ED, Oliveira JT, Mellin C, Lee S, Saber WA, Wang A, Ichida JK, Chiu IM, Barrett L, Huebner EA, Bilgin C, Tsujimoto N, Brenneis C, Kapur K, Rubin LL, Eggan K, Woolf CJ. Modeling pain in vitro using nociceptor neurons reprogrammed from fibroblasts. Nat Neurosci 2015; 18:17-24. [PMID: 25420066 PMCID: PMC4429606 DOI: 10.1038/nn.3886] [Citation(s) in RCA: 162] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Accepted: 10/29/2014] [Indexed: 02/08/2023]
Abstract
Reprogramming somatic cells from one cell fate to another can generate specific neurons suitable for disease modeling. To maximize the utility of patient-derived neurons, they must model not only disease-relevant cell classes, but also the diversity of neuronal subtypes found in vivo and the pathophysiological changes that underlie specific clinical diseases. We identified five transcription factors that reprogram mouse and human fibroblasts into noxious stimulus-detecting (nociceptor) neurons. These recapitulated the expression of quintessential nociceptor-specific functional receptors and channels found in adult mouse nociceptor neurons, as well as native subtype diversity. Moreover, the derived nociceptor neurons exhibited TrpV1 sensitization to the inflammatory mediator prostaglandin E2 and the chemotherapeutic drug oxaliplatin, modeling the inherent mechanisms underlying inflammatory pain hypersensitivity and painful chemotherapy-induced neuropathy. Using fibroblasts from patients with familial dysautonomia (hereditary sensory and autonomic neuropathy type III), we found that the technique was able to reveal previously unknown aspects of human disease phenotypes in vitro.
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Affiliation(s)
- Brian J. Wainger
- FM Kirby Neurobiology Center, Boston Children's Hospital
and Harvard Stem Cell Institute
- Department of Anesthesia, Critical Care and Pain Medicine,
Massachusetts General Hospital
- Department of Neurobiology, Harvard Medical School
| | - Elizabeth D. Buttermore
- FM Kirby Neurobiology Center, Boston Children's Hospital
and Harvard Stem Cell Institute
- Department of Neurobiology, Harvard Medical School
| | - Julia T. Oliveira
- FM Kirby Neurobiology Center, Boston Children's Hospital
and Harvard Stem Cell Institute
| | - Cassidy Mellin
- FM Kirby Neurobiology Center, Boston Children's Hospital
and Harvard Stem Cell Institute
| | - Seungkyu Lee
- FM Kirby Neurobiology Center, Boston Children's Hospital
and Harvard Stem Cell Institute
- Department of Neurobiology, Harvard Medical School
| | - Wardiya Afshar Saber
- FM Kirby Neurobiology Center, Boston Children's Hospital
and Harvard Stem Cell Institute
| | - Amy Wang
- FM Kirby Neurobiology Center, Boston Children's Hospital
and Harvard Stem Cell Institute
| | - Justin K. Ichida
- Harvard Stem Cell Institute, Department of Stem Cell and
Regenerative Biology, Harvard University
- Department of Stem Cell Biology and Regenerative Medicine, Eli
and Edythe Broad CIRM Center for Regenerative Medicine and Stem Cell Research, University of
Southern California
| | - Isaac M. Chiu
- FM Kirby Neurobiology Center, Boston Children's Hospital
and Harvard Stem Cell Institute
- Department of Neurobiology, Harvard Medical School
| | - Lee Barrett
- FM Kirby Neurobiology Center, Boston Children's Hospital
and Harvard Stem Cell Institute
| | - Eric A. Huebner
- FM Kirby Neurobiology Center, Boston Children's Hospital
and Harvard Stem Cell Institute
- Department of Neurobiology, Harvard Medical School
| | - Canan Bilgin
- FM Kirby Neurobiology Center, Boston Children's Hospital
and Harvard Stem Cell Institute
| | - Naomi Tsujimoto
- Harvard Stem Cell Institute, Department of Stem Cell and
Regenerative Biology, Harvard University
| | - Christian Brenneis
- FM Kirby Neurobiology Center, Boston Children's Hospital
and Harvard Stem Cell Institute
| | - Kush Kapur
- FM Kirby Neurobiology Center, Boston Children's Hospital
and Harvard Stem Cell Institute
| | - Lee L. Rubin
- Harvard Stem Cell Institute, Department of Stem Cell and
Regenerative Biology, Harvard University
| | - Kevin Eggan
- Harvard Stem Cell Institute, Department of Stem Cell and
Regenerative Biology, Harvard University
- The Howard Hughes Medical Institute, USA
| | - Clifford J. Woolf
- FM Kirby Neurobiology Center, Boston Children's Hospital
and Harvard Stem Cell Institute
- Department of Neurobiology, Harvard Medical School
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Francius C, Ravassard P, Hidalgo-Figueroa M, Mallet J, Clotman F, Nardelli J. Genetic dissection of Gata2 selective functions during specification of V2 interneurons in the developing spinal cord. Dev Neurobiol 2014; 75:721-37. [PMID: 25369423 DOI: 10.1002/dneu.22244] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Revised: 10/23/2014] [Accepted: 10/29/2014] [Indexed: 11/09/2022]
Abstract
Motor activities are controlled by neural networks in the ventral spinal cord and consist in motor neurons and a set of distinct cardinal classes of spinal interneurons. These interneurons arise from distinct progenitor domains (p0-p3) delineated according to a transcriptional code. Neural progenitors of each domain express a unique combination of transcription factors (TFs) that largely contribute to determine the fate of four classes of interneurons (V0-V3) and motor neurons. In p2 domain, at least four subtypes of interneurons namely V2a, V2b, V2c, and Pax6(+) V2 are generated. Although genetic and molecular mechanisms that specify V2a and V2b are dependent on complex interplay between several TFs including Nkx6.1, Irx3, Gata2, Foxn4, and Ascl1, and signaling pathways such as Notch and TGF-β, the sequence order of the activation of these regulators and their respective contribution are not completely elucidated yet. Here, we provide evidence by loss- or gain-of-function experiments that Gata2 is necessary for the normal development of both V2a and V2b neurons. We demonstrate that Nkx6.1 and Dll4 positively regulate the activation of Gata2 and Foxn4 in p2 progenitors. Gata2 also participates in the maintenance of p2 domain by repressing motor neuron differentiation and exerting a feedback control on patterning genes. Finally, Gata2 promotes the selective activation of V2b program at the expense of V2a fate. Thus our results provide new insights on the hierarchy and complex interactions between regulators of V2 genetic program.
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Affiliation(s)
- Cédric Francius
- CRICM, UPMC/Inserm UMR_S 975; CNRS UMR 7225, Laboratoire de Biotechnologie et Biotherapie, Hôpital Pitié-Salpêtrière, CERVI, 83 bd de l'Hôpital, F-75013, Paris, France.,Laboratory of Neural Differentiation (NEDI), Université Catholique de Louvain (UCL), Institute of Neuroscience (IoNS), box UCL-5511, 55 Avenue Hippocrate, B-1200 Brussels, Belgium
| | - Philippe Ravassard
- CRICM, UPMC/Inserm UMR_S 975; CNRS UMR 7225, Laboratoire de Biotechnologie et Biotherapie, Hôpital Pitié-Salpêtrière, CERVI, 83 bd de l'Hôpital, F-75013, Paris, France
| | - María Hidalgo-Figueroa
- Laboratory of Neural Differentiation (NEDI), Université Catholique de Louvain (UCL), Institute of Neuroscience (IoNS), box UCL-5511, 55 Avenue Hippocrate, B-1200 Brussels, Belgium
| | - Jacques Mallet
- CRICM, UPMC/Inserm UMR_S 975; CNRS UMR 7225, Laboratoire de Biotechnologie et Biotherapie, Hôpital Pitié-Salpêtrière, CERVI, 83 bd de l'Hôpital, F-75013, Paris, France
| | - Frédéric Clotman
- Laboratory of Neural Differentiation (NEDI), Université Catholique de Louvain (UCL), Institute of Neuroscience (IoNS), box UCL-5511, 55 Avenue Hippocrate, B-1200 Brussels, Belgium
| | - Jeannette Nardelli
- CRICM, UPMC/Inserm UMR_S 975; CNRS UMR 7225, Laboratoire de Biotechnologie et Biotherapie, Hôpital Pitié-Salpêtrière, CERVI, 83 bd de l'Hôpital, F-75013, Paris, France.,Inserm U676, Hôpital Robert Debré, 48 bd Serurier, F-75019, Paris, France
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Zou M, Luo H, Xiang M. Selective neuronal lineages derived from Dll4-expressing progenitors/precursors in the retina and spinal cord. Dev Dyn 2014; 244:86-97. [PMID: 25179941 DOI: 10.1002/dvdy.24185] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Revised: 08/25/2014] [Accepted: 08/26/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND During retinal and spinal cord neurogenesis, Notch signaling plays crucial roles in regulating proliferation and differentiation of progenitor cells. One of the Notch ligands, Delta-like 4 (Dll4), has been shown to be expressed in subsets of retinal and spinal cord progenitors/precursors and involved in neuronal subtype specification. However, it remains to be determined whether Dll4 expression has any progenitor/precursor-specificity contributing to its functional specificity during neural development. RESULTS We generated a Dll4-Cre BAC transgenic mouse line that drives Cre recombinase expression mimicking that of the endogenous Dll4 in the developing retina and spinal cord. By fate-mapping analysis, we found that Dll4-expressing progenitors/precursors give rise to essentially all cone, amacrine and horizontal cells, a large portion of rod and ganglion cells, but only few bipolar and Müller cells. In the spinal cord, Dll4-expressing progenitors/precursors generate almost all V2a and V2c cells while producing only a fraction of the cells for other interneuron and motor neuron subtypes along the dorsoventral axis. CONCLUSIONS Our data suggest that selective expression of Dll4 in progenitors/precursors contributes to its functional specificity in neuronal specification and that the Dll4-Cre line is a valuable tool for gene manipulation to study Notch signaling.
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Affiliation(s)
- Min Zou
- Center for Advanced Biotechnology and Medicine and Department of Pediatrics, Rutgers University-Robert Wood Johnson Medical School, Piscataway, New Jersey
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38
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Brown CR, Butts JC, McCreedy DA, Sakiyama-Elbert SE. Generation of v2a interneurons from mouse embryonic stem cells. Stem Cells Dev 2014; 23:1765-76. [PMID: 24650073 DOI: 10.1089/scd.2013.0628] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
V2a interneurons of the ventral spinal cord and hindbrain play an important role in the central pattern generators (CPGs) involved in locomotion, skilled reaching, and respiration. However, sources of V2a interneurons for in vitro studies are limited. In this study, we developed a differentiation protocol for V2a interneurons from mouse embryonic stem cells (mESCs). Cells were induced in a 2(-)/4(+) induction protocol with varying concentrations of retinoic acid (RA) and the mild sonic hedgehog (Shh) agonist purmorphamine (Pur) in order to increase the expression of V2a interneuron transcription factors (eg, Chx10). Notch signaling, which influences the commitment of p2 progenitor cells to V2a or V2b interneurons, was inhibited in cell cultures to increase the percentage of V2a interneurons. At the end of the induction period, cell commitment was assessed using quantitative real-time polymerase chain reaction, immunocytochemistry, and flow cytometry to quantify expression of transcription factors specific to V2a interneurons and the adjacent ventral spinal cord regions. Low concentrations of RA and high concentrations of Pur led to greater expression of transcription factors specific for V2a interneurons. Notch inhibition favored V2a interneuron over V2b interneuron differentiation. The protocol established in this study can be used to further elucidate the pathways involved in V2a interneuron differentiation and help produce sources of V2a interneurons for developmental neurobiology, electrophysiology, and transplantation studies.
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Affiliation(s)
- Chelsea R Brown
- Department of Biomedical Engineering, Washington University in St. Louis , St. Louis, Missouri
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39
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Achim K, Salminen M, Partanen J. Mechanisms regulating GABAergic neuron development. Cell Mol Life Sci 2014; 71:1395-415. [PMID: 24196748 PMCID: PMC11113277 DOI: 10.1007/s00018-013-1501-3] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2013] [Revised: 10/10/2013] [Accepted: 10/14/2013] [Indexed: 12/17/2022]
Abstract
Neurons using gamma-aminobutyric acid (GABA) as their neurotransmitter are the main inhibitory neurons in the mature central nervous system (CNS) and show great variation in their form and function. GABAergic neurons are produced in all of the main domains of the CNS, where they develop from discrete regions of the neuroepithelium. Here, we review the gene expression and regulatory mechanisms controlling the main steps of GABAergic neuron development: early patterning of the proliferative neuroepithelium, production of postmitotic neural precursors, establishment of their identity and migration. By comparing the molecular regulation of these events across CNS, we broadly identify three regions utilizing distinct molecular toolkits for GABAergic fate determination: telencephalon-anterior diencephalon (DLX2 type), posterior diencephalon-midbrain (GATA2 type) and hindbrain-spinal cord (PTF1A and TAL1 types). Similarities and differences in the molecular regulatory mechanisms reveal the core determinants of a GABAergic neuron as well as provide insights into generation of the vast diversity of these neurons.
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Affiliation(s)
- Kaia Achim
- EMBL Heidelberg, Meyerhofstr. 1, 69117 Heidelberg, Germany
| | - Marjo Salminen
- Department of Veterinary Biosciences, University of Helsinki, Agnes Sjobergin katu 2, PO Box 66, 00014 Helsinki, Finland
| | - Juha Partanen
- Department of Biosciences, University of Helsinki, Viikinkaari 5, PO Box 56, 00014 Helsinki, Finland
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40
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Abstract
Motor behaviors result from the interplay between the brain and the spinal cord. Reticulospinal neurons, situated between the supraspinal structures that initiate motor movements and the spinal cord that executes them, play key integrative roles in these behaviors. However, the molecular identities of mammalian reticular formation neurons that mediate motor behaviors have not yet been determined, thus limiting their study in health and disease. In the medullary reticular formation of the mouse, we identified neurons that express the transcription factors Lhx3 and/or Chx10, and demonstrate that these neurons form a significant component of glutamatergic reticulospinal pathways. Lhx3-positive medullary reticular formation neurons express Fos following a locomotor task in the adult, indicating that they are active during walking. Furthermore, they receive functional inputs from the mesencephalic locomotor region and have electrophysiological properties to support tonic repetitive firing, both of which are necessary for neurons that mediate the descending command for locomotion. Together, these results suggest that Lhx3/Chx10 medullary reticular formation neurons are involved in locomotion.
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Misra K, Luo H, Li S, Matise M, Xiang M. Asymmetric activation of Dll4-Notch signaling by Foxn4 and proneural factors activates BMP/TGFβ signaling to specify V2b interneurons in the spinal cord. Development 2013; 141:187-98. [PMID: 24257627 DOI: 10.1242/dev.092536] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
During development of the ventral spinal cord, the V2 interneurons emerge from p2 progenitors and diversify into two major subtypes, V2a and V2b, that play key roles in locomotor coordination. Dll4-mediated Notch activation in a subset of p2 precursors constitutes the crucial first step towards generating neuronal diversity in this domain. The mechanism behind the asymmetric Notch activation and downstream signaling events are, however, unknown at present. We show here that the Ascl1 and Neurog basic helix-loop-helix (bHLH) proneural factors are expressed in a mosaic pattern in p2 progenitors and that Foxn4 is required for setting and maintaining this expression mosaic. By binding directly to a conserved Dll4 enhancer, Foxn4 and Ascl1 activate Dll4 expression, whereas Neurog proteins prevent this effect, thereby resulting in asymmetric activation of Dll4 expression in V2 precursors expressing different combinations of proneural and Foxn4 transcription factors. Lineage tracing using the Cre-LoxP system reveals selective expression of Dll4 in V2a precursors, whereas Dll4 expression is initially excluded from V2b precursors. We provide evidence that BMP/TGFβ signaling is activated in V2b precursors and that Dll4-mediated Notch signaling is responsible for this activation. Using a gain-of-function approach and by inhibiting BMP/TGFβ signal transduction with pathway antagonists and RNAi knockdown, we further demonstrate that BMP/TGFβ signaling is both necessary and sufficient for V2b fate specification. Our data together thus suggest that the mosaic expression of Foxn4 and proneural factors may serve as the trigger to initiate asymmetric Dll4-Notch and subsequent BMP/TGFβ signaling events required for neuronal diversity in the V2 domain.
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Affiliation(s)
- Kamana Misra
- Center for Advanced Biotechnology and Medicine and Department of Pediatrics, Rutgers University-Robert Wood Johnson Medical School, 679 Hoes Lane West, Piscataway, NJ 08854, USA
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42
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Locomotor Rhythm Generation Linked to the Output of Spinal Shox2 Excitatory Interneurons. Neuron 2013; 80:920-33. [DOI: 10.1016/j.neuron.2013.08.015] [Citation(s) in RCA: 162] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/09/2013] [Indexed: 12/13/2022]
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43
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Spinal inhibitory circuits and their role in motor neuron degeneration. Neuropharmacology 2013; 82:101-7. [PMID: 24157492 DOI: 10.1016/j.neuropharm.2013.10.003] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2013] [Revised: 10/01/2013] [Accepted: 10/04/2013] [Indexed: 12/12/2022]
Abstract
In the spinal cord neuronal activity is controlled by the balance between excitatory and inhibitory neurotransmission, mediated mainly by the neurotransmitters glutamate and GABA/glycine, respectively. Alterations of this equilibrium have been associated with spinal motor neuron hyperexcitability and degeneration, which can be induced by excitotoxicity or by decreasing inhibitory neurotransmission. Here we review the ventral horn neuronal network and the possible involvement of inhibitory circuits in the mechanisms of degeneration of motor neurons characteristic of amyotrophic lateral sclerosis (ALS). Whereas glutamate mediated excitotoxicity seems to be an important factor, recent experimental and histopathological evidence argue in favor of a decreased activity of the inhibitory circuits controlling motor neuron excitability, mainly the recurrent inhibition exerted by Renshaw cells. A decreased Renshaw cell activity may be caused by cell loss or by a reduction of its inhibitory action secondary to a decreased excitation from cholinergic interneurons. Ultimately, inhibitory failure by either mechanism might lead to motor neuron degeneration, and this suggests inhibitory circuits and Renshaw cells as pharmacologic targets for ALS treatment.
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44
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Karnavas T, Mandalos N, Malas S, Remboutsika E. SoxB, cell cycle and neurogenesis. Front Physiol 2013; 4:298. [PMID: 24146653 PMCID: PMC3797971 DOI: 10.3389/fphys.2013.00298] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2013] [Accepted: 09/29/2013] [Indexed: 11/13/2022] Open
Affiliation(s)
- Theodoros Karnavas
- Stem Cell Biology Laboratory, Biomedical Sciences Research Centre "Alexander Fleming" Vari-Attica, Greece
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45
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Foxn4: a multi-faceted transcriptional regulator of cell fates in vertebrate development. SCIENCE CHINA-LIFE SCIENCES 2013; 56:985-93. [PMID: 24008385 DOI: 10.1007/s11427-013-4543-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2013] [Accepted: 08/12/2013] [Indexed: 12/12/2022]
Abstract
Vertebrate development culminates in the generation of proper proportions of a large variety of different cell types and subtypes essential for tissue, organ and system functions in the right place at the right time. Foxn4, a member of the forkhead box/winged-helix transcription factor superfamily, is expressed in mitotic progenitors and/or postmitotic precursors in both neural (e.g., retina and spinal cord) and non-neural tissues (e.g., atrioventricular canal and proximal airway). During development of the central nervous system, Foxn4 is required to specify the amacrine and horizontal cell fates from multipotent retinal progenitors while suppressing the alternative photoreceptor cell fates through activating Dll4-Notch signaling. Moreover, it activates Dll4-Notch signaling to drive commitment of p2 progenitors to the V2b and V2c interneuron fates during spinal cord neurogenesis. In development of non-neural tissues, Foxn4 plays an essential role in the specification of the atrioventricular canal and is indirectly required for patterning the distal airway during lung development. In this review, we highlight current understanding of the structure, expression and developmental functions of Foxn4 with an emphasis on its cell-autonomous and non-cell-autonomous roles in different tissues and animal model systems.
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46
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Francius C, Harris A, Rucchin V, Hendricks TJ, Stam FJ, Barber M, Kurek D, Grosveld FG, Pierani A, Goulding M, Clotman F. Identification of multiple subsets of ventral interneurons and differential distribution along the rostrocaudal axis of the developing spinal cord. PLoS One 2013; 8:e70325. [PMID: 23967072 PMCID: PMC3744532 DOI: 10.1371/journal.pone.0070325] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2013] [Accepted: 06/17/2013] [Indexed: 01/06/2023] Open
Abstract
The spinal cord contains neuronal circuits termed Central Pattern Generators (CPGs) that coordinate rhythmic motor activities. CPG circuits consist of motor neurons and multiple interneuron cell types, many of which are derived from four distinct cardinal classes of ventral interneurons, called V0, V1, V2 and V3. While significant progress has been made on elucidating the molecular and genetic mechanisms that control ventral interneuron differentiation, little is known about their distribution along the antero-posterior axis of the spinal cord and their diversification. Here, we report that V0, V1 and V2 interneurons exhibit distinct organizational patterns at brachial, thoracic and lumbar levels of the developing spinal cord. In addition, we demonstrate that each cardinal class of ventral interneurons can be subdivided into several subsets according to the combinatorial expression of different sets of transcription factors, and that these subsets are differentially distributed along the rostrocaudal axis of the spinal cord. This comprehensive molecular profiling of ventral interneurons provides an important resource for investigating neuronal diversification in the developing spinal cord and for understanding the contribution of specific interneuron subsets on CPG circuits and motor control.
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Affiliation(s)
- Cédric Francius
- Université catholique de Louvain, Institute of Neuroscience, Laboratory of Neural Differentiation, Brussels, Belgium
| | - Audrey Harris
- Université catholique de Louvain, Institute of Neuroscience, Laboratory of Neural Differentiation, Brussels, Belgium
| | - Vincent Rucchin
- Université catholique de Louvain, Institute of Neuroscience, Laboratory of Neural Differentiation, Brussels, Belgium
| | - Timothy J. Hendricks
- Molecular Neurobiology Laboratory, The Salk Institute for Biological Studies, La Jolla, California, United States of America
| | - Floor J. Stam
- Molecular Neurobiology Laboratory, The Salk Institute for Biological Studies, La Jolla, California, United States of America
| | - Melissa Barber
- CNRS UMR 7592, Institut Jacques Monod, Université Paris Diderot, Sorbonne Paris Cité, Paris, France
| | - Dorota Kurek
- Erasmus MC Stem Cell Institute, Department of Cell Biology, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Frank G. Grosveld
- Erasmus MC Stem Cell Institute, Department of Cell Biology, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Alessandra Pierani
- CNRS UMR 7592, Institut Jacques Monod, Université Paris Diderot, Sorbonne Paris Cité, Paris, France
| | - Martyn Goulding
- Molecular Neurobiology Laboratory, The Salk Institute for Biological Studies, La Jolla, California, United States of America
| | - Frédéric Clotman
- Université catholique de Louvain, Institute of Neuroscience, Laboratory of Neural Differentiation, Brussels, Belgium
- * E-mail:
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47
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Panayiotou E, Panayi E, Lapathitis G, Francius C, Clotman F, Kessaris N, Richardson WD, Malas S. Pax6 is expressed in subsets of V0 and V2 interneurons in the ventral spinal cord in mice. Gene Expr Patterns 2013; 13:328-34. [PMID: 23816521 DOI: 10.1016/j.gep.2013.06.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2013] [Revised: 06/18/2013] [Accepted: 06/20/2013] [Indexed: 02/06/2023]
Abstract
The embryonic spinal cord in mice is organized into eleven progenitor domains. Cells in each domain first produce neurons and then switch to specifying glia. Five of these domains known as p3, pMN, p2, p1 and p0 are located in the ventral spinal cord and each expresses a unique code of transcription factors (TFs) that define the molecular profile of progenitor cells. This code is largely responsible for determining the subtype specification of neurons generated from each domain. Pax6 codes for a homedomain-containing TF that plays a central role in defining the molecular boundaries between the two ventral-most domains, p3 and pMN. Using fate mapping and gene expression studies we show that PAX6, in addition to each patterning function, is expressed in a group of late born interneurons that derive from the p2 and p0 domains. The p2-derived neurons represent a subset of late born V2b interneurons and their specification depends on Notch signaling. The V0 neurons represent V0v ventral neurons expressing Pax2. Our data demonstrate that interneuron diversity in the ventral spinal cord is more complex than originally appreciated and point to the existence of additional mechanisms that determine interneuron diversity, particularly in the p2 domain.
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Affiliation(s)
- Elena Panayiotou
- The Cyprus Institute of Neurology and Genetics, P.O. Box 23462, 1683 Nicosia, Cyprus; Department of Biological Sciences, University of Cyprus, P.O. Box 20537, 1678 Nicosia, Cyprus
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48
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Cocks G, Romanyuk N, Amemori T, Jendelova P, Forostyak O, Jeffries AR, Perfect L, Thuret S, Dayanithi G, Sykova E, Price J. Conditionally immortalized stem cell lines from human spinal cord retain regional identity and generate functional V2a interneurons and motorneurons. Stem Cell Res Ther 2013; 4:69. [PMID: 23759128 PMCID: PMC3706922 DOI: 10.1186/scrt220] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2012] [Accepted: 06/03/2013] [Indexed: 01/24/2023] Open
Abstract
Introduction The use of immortalized neural stem cells either as models of neural development in vitro or as cellular therapies in central nervous system (CNS) disorders has been controversial. This controversy has centered on the capacity of immortalized cells to retain characteristic features of the progenitor cells resident in the tissue of origin from which they were derived, and the potential for tumorogenicity as a result of immortalization. Here, we report the generation of conditionally immortalized neural stem cell lines from human fetal spinal cord tissue, which addresses these issues. Methods Clonal neural stem cell lines were derived from 10-week-old human fetal spinal cord and conditionally immortalized with an inducible form of cMyc. The derived lines were karyotyped, transcriptionally profiled by microarray, and assessed against a panel of spinal cord progenitor markers with immunocytochemistry. In addition, the lines were differentiated and assessed for the presence of neuronal fate markers and functional calcium channels. Finally, a clonal line expressing eGFP was grafted into lesioned rat spinal cord and assessed for survival, differentiation characteristics, and tumorogenicity. Results We demonstrate that these clonal lines (a) retain a clear transcriptional signature of ventral spinal cord progenitors and a normal karyotype after extensive propagation in vitro, (b) differentiate into relevant ventral neuronal subtypes with functional T-, L-, N-, and P/Q-type Ca2+ channels and spontaneous calcium oscillations, and (c) stably engraft into lesioned rat spinal cord without tumorogenicity. Conclusions We propose that these cells represent a useful tool both for the in vitro study of differentiation into ventral spinal cord neuronal subtypes, and for examining the potential of conditionally immortalized neural stem cells to facilitate functional recovery after spinal cord injury or disease.
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49
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Kang K, Lee D, Hong S, Park SG, Song MR. The E3 ligase Mind bomb-1 (Mib1) modulates Delta-Notch signaling to control neurogenesis and gliogenesis in the developing spinal cord. J Biol Chem 2012; 288:2580-92. [PMID: 23223237 DOI: 10.1074/jbc.m112.398263] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The Notch signaling pathway is essential for neuronal and glial specification during CNS development. Mind bomb-1 (Mib1) is an E3 ubiquitin ligase that ubiquitinates and promotes the endocytosis of Notch ligands. Although Mib1 is essential for transmitting the Notch signal, it is still unclear whether it is a primary regulator of Notch ligand activity in the developing spinal cord. In Mib1 conditional knock-out mice, we observed depletion of spinal progenitors, premature differentiation of neurons, and unbalanced specification of V2 interneurons, all of which mimic the conventional Notch phenotype. In agreement with this, the reduction of progenitors in the absence of Mib1 led to a loss of both astrocytes and oligodendrocytes. Late removal of Mib1 using a drug-inducible system suppressed glial differentiation, suggesting that Mib1 continues to play a role in the formation of late progenitors mainly designated for gliogenesis. Finally, misexpression of Mib1 or Mib1 deletion mutants revealed that the ring domain of Mib1 is required for the specification of V2 interneurons in the chick neural tube. Together, these findings suggest that Mib1 is a major component of the signal-sending cells required to provide Notch ligand activity for specifying neurons and glia in the spinal cord.
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Affiliation(s)
- Kyungjoon Kang
- School of Life Sciences, Bioimaging Research Center, Gwangju Institute of Science and Technology, Oryong-dong, Buk-gu, Gwangju 500-712, Republic of Korea
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50
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Arber S. Motor Circuits in Action: Specification, Connectivity, and Function. Neuron 2012; 74:975-89. [DOI: 10.1016/j.neuron.2012.05.011] [Citation(s) in RCA: 187] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/14/2012] [Indexed: 10/28/2022]
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