1
|
André M, Dinvaut S, Castellani V, Falk J. 3D exploration of gene expression in chicken embryos through combined RNA fluorescence in situ hybridization, immunofluorescence, and clearing. BMC Biol 2024; 22:131. [PMID: 38831263 PMCID: PMC11149291 DOI: 10.1186/s12915-024-01922-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Accepted: 05/16/2024] [Indexed: 06/05/2024] Open
Abstract
BACKGROUND Fine characterization of gene expression patterns is crucial to understand many aspects of embryonic development. The chicken embryo is a well-established and valuable animal model for developmental biology. The period spanning from the third to sixth embryonic days (E3 to E6) is critical for many organ developments. Hybridization chain reaction RNA fluorescent in situ hybridization (HCR RNA-FISH) enables multiplex RNA detection in thick samples including embryos of various animal models. However, its use is limited by tissue opacity. RESULTS We optimized HCR RNA-FISH protocol to efficiently label RNAs in whole mount chicken embryos from E3.5 to E5.5 and adapted it to ethyl cinnamate (ECi) tissue clearing. We show that light sheet imaging of HCR RNA-FISH after ECi clearing allows RNA expression analysis within embryonic tissues with good sensitivity and spatial resolution. Finally, whole mount immunofluorescence can be performed after HCR RNA-FISH enabling as exemplified to assay complex spatial relationships between axons and their environment or to monitor GFP electroporated neurons. CONCLUSIONS We could extend the use of HCR RNA-FISH to older chick embryos by optimizing HCR RNA-FISH and combining it with tissue clearing and 3D imaging. The integration of immunostaining makes possible to combine gene expression with classical cell markers, to correlate expressions with morphological differentiation and to depict gene expressions in gain or loss of function contexts. Altogether, this combined procedure further extends the potential of HCR RNA-FISH technique for chicken embryology.
Collapse
Affiliation(s)
- Maëlys André
- MeLiS, CNRS UMR 5284 - INSERM U1314, Université Claude Bernard Lyon 1, 8 avenue Rockefeller, 69008, Lyon, France.
| | - Sarah Dinvaut
- MeLiS, CNRS UMR 5284 - INSERM U1314, Université Claude Bernard Lyon 1, 8 avenue Rockefeller, 69008, Lyon, France
| | - Valérie Castellani
- MeLiS, CNRS UMR 5284 - INSERM U1314, Université Claude Bernard Lyon 1, 8 avenue Rockefeller, 69008, Lyon, France
| | - Julien Falk
- MeLiS, CNRS UMR 5284 - INSERM U1314, Université Claude Bernard Lyon 1, 8 avenue Rockefeller, 69008, Lyon, France.
| |
Collapse
|
2
|
Wu D, Khan FA, Zhang K, Pandupuspitasari NS, Negara W, Guan K, Sun F, Huang C. Retinoic acid signaling in development and differentiation commitment and its regulatory topology. Chem Biol Interact 2024; 387:110773. [PMID: 37977248 DOI: 10.1016/j.cbi.2023.110773] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Revised: 10/11/2023] [Accepted: 10/20/2023] [Indexed: 11/19/2023]
Abstract
Retinoic acid (RA), the derivative of vitamin A/retinol, is a signaling molecule with important implications in health and disease. It is a well-known developmental morphogen that functions mainly through the transcriptional activity of nuclear RA receptors (RARs) and, uncommonly, through other nuclear receptors, including peroxisome proliferator-activated receptors. Intracellular RA is under spatiotemporally fine-tuned regulation by synthesis and degradation processes catalyzed by retinaldehyde dehydrogenases and P450 family enzymes, respectively. In addition to dictating the transcription architecture, RA also impinges on cell functioning through non-genomic mechanisms independent of RAR transcriptional activity. Although RA-based differentiation therapy has achieved impressive success in the treatment of hematologic malignancies, RA also has pro-tumor activity. Here, we highlight the relevance of RA signaling in cell-fate determination, neurogenesis, visual function, inflammatory responses and gametogenesis commitment. Genetic and post-translational modifications of RAR are also discussed. A better understanding of RA signaling will foster the development of precision medicine to improve the defects caused by deregulated RA signaling.
Collapse
Affiliation(s)
- Di Wu
- Institute of Reproductive Medicine, School of Medicine, Nantong University, Nantong, 226001, China
| | - Faheem Ahmed Khan
- Research Center for Animal Husbandry, National Research and Innovation Agency, Jakarta Pusat, 10340, Indonesia
| | - Kejia Zhang
- Institute of Reproductive Medicine, School of Medicine, Nantong University, Nantong, 226001, China
| | | | - Windu Negara
- Research Center for Animal Husbandry, National Research and Innovation Agency, Jakarta Pusat, 10340, Indonesia
| | - Kaifeng Guan
- School of Advanced Agricultural Sciences, Peking University, Beijing, 100871, China.
| | - Fei Sun
- Institute of Reproductive Medicine, School of Medicine, Nantong University, Nantong, 226001, China.
| | - Chunjie Huang
- Institute of Reproductive Medicine, School of Medicine, Nantong University, Nantong, 226001, China.
| |
Collapse
|
3
|
Koshy AM, Mendoza-Parra MA. Retinoids: Mechanisms of Action in Neuronal Cell Fate Acquisition. Life (Basel) 2023; 13:2279. [PMID: 38137880 PMCID: PMC10744663 DOI: 10.3390/life13122279] [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: 10/19/2023] [Revised: 11/22/2023] [Accepted: 11/28/2023] [Indexed: 12/24/2023] Open
Abstract
Neuronal differentiation has been shown to be directed by retinoid action during embryo development and has been exploited in various in vitro cell differentiation systems. In this review, we summarize the role of retinoids through the activation of their specific retinoic acid nuclear receptors during embryo development and also in a variety of in vitro strategies for neuronal differentiation, including recent efforts in driving cell specialization towards a range of neuronal subtypes and glial cells. Finally, we highlight the role of retinoic acid in recent protocols recapitulating nervous tissue complexity (cerebral organoids). Overall, we expect that this effort might pave the way for exploring the usage of specific synthetic retinoids for directing complex nervous tissue differentiation.
Collapse
Affiliation(s)
| | - Marco Antonio Mendoza-Parra
- UMR 8030 Génomique Métabolique, Genoscope, Institut François Jacob, CEA, CNRS, University of Evry-val-d’Essonne, University Paris-Saclay, 91057 Évry, France;
| |
Collapse
|
4
|
Blassberg R, Patel H, Watson T, Gouti M, Metzis V, Delás MJ, Briscoe J. Sox2 levels regulate the chromatin occupancy of WNT mediators in epiblast progenitors responsible for vertebrate body formation. Nat Cell Biol 2022; 24:633-644. [PMID: 35550614 PMCID: PMC9106585 DOI: 10.1038/s41556-022-00910-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Accepted: 03/29/2022] [Indexed: 02/07/2023]
Abstract
WNT signalling has multiple roles. It maintains pluripotency of embryonic stem cells, assigns posterior identity in the epiblast and induces mesodermal tissue. Here we provide evidence that these distinct functions are conducted by the transcription factor SOX2, which adopts different modes of chromatin interaction and regulatory element selection depending on its level of expression. At high levels, SOX2 displaces nucleosomes from regulatory elements with high-affinity SOX2 binding sites, recruiting the WNT effector TCF/β-catenin and maintaining pluripotent gene expression. Reducing SOX2 levels destabilizes pluripotency and reconfigures SOX2/TCF/β-catenin occupancy to caudal epiblast expressed genes. These contain low-affinity SOX2 sites and are co-occupied by T/Bra and CDX. The loss of SOX2 allows WNT-induced mesodermal differentiation. These findings define a role for Sox2 levels in dictating the chromatin occupancy of TCF/β-catenin and reveal how context-specific responses to a signal are configured by the level of a transcription factor.
Collapse
Affiliation(s)
| | | | | | - Mina Gouti
- Stem Cell Modelling of Development & Disease Group, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - Vicki Metzis
- The Francis Crick Institute, London, UK
- Institute of Clinical Sciences, Imperial College London, London, UK
| | | | | |
Collapse
|
5
|
Retinoids and developmental neurotoxicity: Utilizing toxicogenomics to enhance adverse outcome pathways and testing strategies. Reprod Toxicol 2020; 96:102-113. [PMID: 32544423 DOI: 10.1016/j.reprotox.2020.06.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2020] [Revised: 06/02/2020] [Accepted: 06/07/2020] [Indexed: 12/17/2022]
Abstract
The use of genomic approaches in toxicological studies has greatly increased our ability to define the molecular profiles of environmental chemicals associated with developmental neurotoxicity (DNT). Integration of these approaches with adverse outcome pathways (AOPs), a framework that translates environmental exposures to adverse developmental phenotypes, can potentially inform DNT testing strategies. Here, using retinoic acid (RA) as a case example, we demonstrate that the integration of toxicogenomic profiles into the AOP framework can be used to establish a paradigm for chemical testing. RA is a critical regulatory signaling molecule involved in multiple aspects of mammalian central nervous system (CNS) development, including hindbrain formation/patterning and neuronal differentiation, and imbalances in RA signaling pathways are linked with DNT. While the mechanisms remain unresolved, environmental chemicals can cause DNT by disrupting the RA signaling pathway. First, we reviewed literature evidence of RA and other retinoid exposures and DNT to define a provisional AOP related to imbalances in RA embryonic bioavailability and hindbrain development. Next, by integrating toxicogenomic datasets, we defined a relevant transcriptomic signature associated with RA-induced developmental neurotoxicity (RA-DNT) in human and rodent models that was tested against zebrafish model data, demonstrating potential for integration into an AOP framework. Finally, we demonstrated how these approaches may be systematically utilized to identify chemical hazards by testing the RA-DNT signature against azoles, a proposed class of compounds that alters RA-signaling. The provisional AOP from this study can be expanded in the future to better define DNT biomarkers relevant to RA signaling and toxicity.
Collapse
|
6
|
Raina A, Mahajani S, Bähr M, Kügler S. Neuronal Trans-differentiation by Transcription Factors Ascl1 and Nurr1: Induction of a Dopaminergic Neurotransmitter Phenotype in Cortical GABAergic Neurons. Mol Neurobiol 2019; 57:249-260. [PMID: 31317490 DOI: 10.1007/s12035-019-01701-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Accepted: 07/09/2019] [Indexed: 12/17/2022]
Abstract
Neurons with a desired neurotransmitter phenotype can be differentiated from induced pluripotent stem cells or from somatic cells only through tedious protocols with relatively low yield. Readily available cortical neurons isolated from embryonic rat brain, which have already undergone a complete neuronal differentiation process, might serve as alternative template source. These cultures consist of 85% glutamatergic and 15% GABAergic neurons, and we attempted to trans-differentiate them into dopaminergic neurons. Transcription factors Nurr1, Lmx1A and Pitx3, essential determinants of a dopaminergic cell fate during CNS development, were not sufficient to induce tyrosine hydroxylase expression in a significant number of cells. Combining Nurr1 with the generic neuronal differentiator and re-programming factor Ascl1, however, resulted in generation of neurons which express dopaminergic markers TH, AADC, VMAT2 and DAT. Only neurons of GABAergic phenotype could be trans-differentiated towards a dopaminergic neurotransmitter phenotype, while for glutamatergic neurons, this process proved to be neurotoxic. Intriguingly, GABAergic neurons isolated from embryonal midbrain could not be trans-differentiated into dopaminergic neurons by Ascl1 and Nurr1. Thus, in principle, post-mitotic embryonal neurons can serve as templates for neurons with a desired neurotransmitter phenotype. However, neurotransmitter phenotype plasticity critically depends on the differentiation history of the template neurons, which can result in relatively low yields of dopaminergic neurons.
Collapse
Affiliation(s)
- Anupam Raina
- Department of Neurology, University Medicine Göttingen, Waldweg 33, 37073, Göttingen, Germany.,Center Nanoscale Microscopy and Physiology of the Brain (CNMPB), Göttingen, Germany
| | - Sameehan Mahajani
- Department of Neurology, University Medicine Göttingen, Waldweg 33, 37073, Göttingen, Germany.,Center Nanoscale Microscopy and Physiology of the Brain (CNMPB), Göttingen, Germany
| | - Mathias Bähr
- Department of Neurology, University Medicine Göttingen, Waldweg 33, 37073, Göttingen, Germany.,Center Nanoscale Microscopy and Physiology of the Brain (CNMPB), Göttingen, Germany
| | - Sebastian Kügler
- Department of Neurology, University Medicine Göttingen, Waldweg 33, 37073, Göttingen, Germany. .,Center Nanoscale Microscopy and Physiology of the Brain (CNMPB), Göttingen, Germany.
| |
Collapse
|
7
|
Cheng X, Tan Z, Huang X, Yuan Y, Qin S, Gu Y, Wang D, He C, Su Z. Inhibition of Glioma Development by ASCL1-Mediated Direct Neuronal Reprogramming. Cells 2019; 8:cells8060571. [PMID: 31212628 PMCID: PMC6627512 DOI: 10.3390/cells8060571] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Revised: 06/08/2019] [Accepted: 06/10/2019] [Indexed: 12/27/2022] Open
Abstract
Direct conversion of non-neural cells into induced neurons holds great promise for brain repair. As the most common malignant tumor in the central nervous system, glioma is currently incurable due to its exponential growth and invasive behavior. Given that neurons are irreversible postmitotic cells, reprogramming glioma cells into terminally differentiated neuron-like cells represents a potential approach to inhibit brain tumor development. We here show that human glioma cells can be directly, rapidly and efficiently reprogrammed into terminally differentiated neuron-like cells by the single transcription factor ASCL1 (Achaete-scute complex-like 1, also known as MASH1). These induced cells exhibit typical neuron-like morphology and express multiple neuron-specific markers. Importantly, ASCL1-mediated neuronal reprogramming drives human glioma cells to exit the cell cycle and results in dramatic inhibition of proliferation, both in vitro and in vivo. Taken together, this proof-of-principle study demonstrates a potential strategy for impeding brain tumor development by ASCL1-induced direct neuronal reprogramming.
Collapse
Affiliation(s)
- Xueyan Cheng
- Center for Brain Disorders Research, Capital Medical University; Center of Neural Injury and Repair, Beijing Institute for Brain Disorders, Beijing 100020, China.
- Institute of Neuroscience, Key Laboratory of Molecular Neurobiology of Ministry of Education and the Collaborative Innovation Center for Brain Science, Second Military Medical University, Shanghai 200433, China.
| | - Zijian Tan
- Institute of Neuroscience, Key Laboratory of Molecular Neurobiology of Ministry of Education and the Collaborative Innovation Center for Brain Science, Second Military Medical University, Shanghai 200433, China.
| | - Xiao Huang
- Institute of Neuroscience, Key Laboratory of Molecular Neurobiology of Ministry of Education and the Collaborative Innovation Center for Brain Science, Second Military Medical University, Shanghai 200433, China.
| | - Yimin Yuan
- Institute of Neuroscience, Key Laboratory of Molecular Neurobiology of Ministry of Education and the Collaborative Innovation Center for Brain Science, Second Military Medical University, Shanghai 200433, China.
| | - Shangyao Qin
- Institute of Neuroscience, Key Laboratory of Molecular Neurobiology of Ministry of Education and the Collaborative Innovation Center for Brain Science, Second Military Medical University, Shanghai 200433, China.
| | - Yakun Gu
- Center for Brain Disorders Research, Capital Medical University; Center of Neural Injury and Repair, Beijing Institute for Brain Disorders, Beijing 100020, China.
- Institute of Neuroscience, Key Laboratory of Molecular Neurobiology of Ministry of Education and the Collaborative Innovation Center for Brain Science, Second Military Medical University, Shanghai 200433, China.
| | - Dan Wang
- Institute of Neuroscience, Key Laboratory of Molecular Neurobiology of Ministry of Education and the Collaborative Innovation Center for Brain Science, Second Military Medical University, Shanghai 200433, China.
| | - Cheng He
- Center for Brain Disorders Research, Capital Medical University; Center of Neural Injury and Repair, Beijing Institute for Brain Disorders, Beijing 100020, China.
- Institute of Neuroscience, Key Laboratory of Molecular Neurobiology of Ministry of Education and the Collaborative Innovation Center for Brain Science, Second Military Medical University, Shanghai 200433, China.
| | - Zhida Su
- Institute of Neuroscience, Key Laboratory of Molecular Neurobiology of Ministry of Education and the Collaborative Innovation Center for Brain Science, Second Military Medical University, Shanghai 200433, China.
| |
Collapse
|
8
|
Peterson J, Lin B, Barrios-Camacho CM, Herrick DB, Holbrook EH, Jang W, Coleman JH, Schwob JE. Activating a Reserve Neural Stem Cell Population In Vitro Enables Engraftment and Multipotency after Transplantation. Stem Cell Reports 2019; 12:680-695. [PMID: 30930245 PMCID: PMC6450498 DOI: 10.1016/j.stemcr.2019.02.014] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Revised: 02/27/2019] [Accepted: 02/28/2019] [Indexed: 12/17/2022] Open
Abstract
The olfactory epithelium (OE) regenerates after injury via two types of tissue stem cells: active globose cells (GBCs) and dormant horizontal basal cells (HBCs). HBCs are roused to activated status by OE injury when P63 levels fall. However, an in-depth understanding of activation requires a system for culturing them that maintains both their self-renewal and multipotency while preventing spontaneous differentiation. Here, we demonstrate that mouse, rat, and human HBCs can be cultured and passaged as P63+ multipotent cells. HBCs in vitro closely resemble HBCs in vivo based on immunocytochemical and transcriptomic comparisons. Genetic lineage analysis demonstrates that HBCs in culture arise from both tissue-derived HBCs and multipotent GBCs. Treatment with retinoic acid induces neuronal and non-neuronal differentiation and primes cultured HBCs for transplantation into the lesioned OE. Engrafted HBCs generate all OE cell types, including olfactory sensory neurons, confirming that HBC multipotency and neurocompetency are maintained in culture.
Collapse
Affiliation(s)
- Jesse Peterson
- Department of Developmental, Molecular & Chemical Biology, Tufts University School of Medicine, Boston, MA 02111, USA; Sackler School of Graduate Biomedical Sciences, Tufts University, Boston, MA 02111, USA
| | - Brian Lin
- Department of Developmental, Molecular & Chemical Biology, Tufts University School of Medicine, Boston, MA 02111, USA; Sackler School of Graduate Biomedical Sciences, Tufts University, Boston, MA 02111, USA
| | - Camila M Barrios-Camacho
- Department of Developmental, Molecular & Chemical Biology, Tufts University School of Medicine, Boston, MA 02111, USA; Sackler School of Graduate Biomedical Sciences, Tufts University, Boston, MA 02111, USA
| | - Daniel B Herrick
- Department of Developmental, Molecular & Chemical Biology, Tufts University School of Medicine, Boston, MA 02111, USA; Sackler School of Graduate Biomedical Sciences, Tufts University, Boston, MA 02111, USA
| | - Eric H Holbrook
- Department of Otolaryngology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA 02114, USA
| | - Woochan Jang
- Department of Developmental, Molecular & Chemical Biology, Tufts University School of Medicine, Boston, MA 02111, USA
| | - Julie H Coleman
- Department of Developmental, Molecular & Chemical Biology, Tufts University School of Medicine, Boston, MA 02111, USA; Sackler School of Graduate Biomedical Sciences, Tufts University, Boston, MA 02111, USA
| | - James E Schwob
- Department of Developmental, Molecular & Chemical Biology, Tufts University School of Medicine, Boston, MA 02111, USA.
| |
Collapse
|
9
|
Chouchane M, Costa MR. Instructing neuronal identity during CNS development and astroglial-lineage reprogramming: Roles of NEUROG2 and ASCL1. Brain Res 2018; 1705:66-74. [PMID: 29510143 DOI: 10.1016/j.brainres.2018.02.045] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Revised: 02/16/2018] [Accepted: 02/27/2018] [Indexed: 01/02/2023]
Abstract
The adult mammalian brain contains an enormous variety of neuronal types, which are generally categorized in large groups, based on their neurochemical identity, hodological properties and molecular markers. This broad classification has allowed the correlation between individual neural progenitor populations and their neuronal progeny, thus contributing to probe the cellular and molecular mechanisms involved in neuronal identity determination during central nervous system (CNS) development. In this review, we discuss the contribution of the proneural genes Neurogenin2 (Neurog2) and Achaete-scute homolog 1 (Ascl1) for the specification of neuronal phenotypes in the developing neocortex, cerebellum and retina. Then, we revise recent data on astroglia cell lineage reprogramming into induced neurons using the same proneural proteins to compare the neuronal phenotypes obtained from astroglial cells originated in those CNS regions. We conclude that Ascl1 and Neurog2 have different contributions to determine neuronal fates, depending on the neural progenitor or astroglial population expressing those proneural factors. Finally, we discuss some possible explanations for these seemingly conflicting effects of Ascl1 and Neurog2 and propose future approaches to further dissect the molecular mechanisms of neuronal identity specification.
Collapse
Affiliation(s)
- Malek Chouchane
- Brain Institute, Federal University of Rio Grande do Norte, Natal 59072-970, Brazil; Neurological Surgery Department, University of California, San Francisco 94158, USA
| | - Marcos R Costa
- Brain Institute, Federal University of Rio Grande do Norte, Natal 59072-970, Brazil.
| |
Collapse
|
10
|
Abstract
The mouse embryo forebrain is the most commonly employed system for studying mammalian neurogenesis during development. However, the highly folded forebrain neuroepithelium is not amenable to wholemount analysis to examine organ-wide neurogenesis patterns. Moreover, defining the mechanisms of forebrain neurogenesis is not necessarily predictive of neurogenesis in other parts of the brain; for example, due to the presence of forebrain-specific progenitor subtypes. The mouse hindbrain provides an alternative model for studying embryonic neurogenesis that is amenable to wholemount analysis, as well as tissue sections to observe the spatiotemporal distribution and behavior of neural progenitors. Moreover, it is easily dissected for other downstream applications, such as cell isolation or molecular biology analysis. As the mouse hindbrain can be readily analyzed in the vast number of cell lineage reporter and mutant mouse strains that have become available, it offers a powerful model for studying the cellular and molecular mechanisms of developmental neurogenesis in a mammalian organism. Here, we present a simple and quick method to use the mouse embryo hindbrain for analyzing mammalian neural progenitor cell (NPC) behavior in wholemount preparations and tissue sections.
Collapse
|
11
|
Todd L, Suarez L, Quinn C, Fischer AJ. Retinoic Acid-Signaling Regulates the Proliferative and Neurogenic Capacity of Müller Glia-Derived Progenitor Cells in the Avian Retina. Stem Cells 2017; 36:392-405. [PMID: 29193451 DOI: 10.1002/stem.2742] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Revised: 10/16/2017] [Accepted: 11/03/2017] [Indexed: 12/26/2022]
Abstract
In the retina, Müller glia have the potential to become progenitor cells with the ability to proliferate and regenerate neurons. However, the ability of Müller glia-derived progenitor cells (MGPCs) to proliferate and produce neurons is limited in higher vertebrates. Using the chick model system, we investigate how retinoic acid (RA)-signaling influences the proliferation and the formation of MGPCs. We observed an upregulation of cellular RA binding proteins (CRABP) in the Müller glia of damaged retinas where the formation of MGPCs is known to occur. Activation of RA-signaling was stimulated, whereas inhibition suppressed the proliferation of MGPCs in damaged retinas and in fibroblast growth factor 2-treated undamaged retinas. Furthermore, inhibition of RA-degradation stimulated the proliferation of MGPCs. Levels of Pax6, Klf4, and cFos were upregulated in MGPCs by RA agonists and downregulated in MGPCs by RA antagonists. Activation of RA-signaling following MGPC proliferation increased the percentage of progeny that differentiated as neurons. Similarly, the combination of RA and insulin-like growth factor 1 (IGF1) significantly increased neurogenesis from retinal progenitors in the circumferential marginal zone (CMZ). In summary, RA-signaling stimulates the formation of proliferating MGPCs and enhances the neurogenic potential of MGPCs and stem cells in the CMZ. Stem Cells 2018;36:392-405.
Collapse
Affiliation(s)
- Levi Todd
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, Ohio, USA
| | - Lilianna Suarez
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, Ohio, USA
| | - Colin Quinn
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, Ohio, USA
| | - Andy J Fischer
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, Ohio, USA
| |
Collapse
|
12
|
Podleśny-Drabiniok A, Sobska J, de Lera AR, Gołembiowska K, Kamińska K, Dollé P, Cebrat M, Krężel W. Distinct retinoic acid receptor (RAR) isotypes control differentiation of embryonal carcinoma cells to dopaminergic or striatopallidal medium spiny neurons. Sci Rep 2017; 7:13671. [PMID: 29057906 PMCID: PMC5651880 DOI: 10.1038/s41598-017-13826-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Accepted: 09/26/2017] [Indexed: 01/03/2023] Open
Abstract
Embryonal carcinoma (EC) cells are pluripotent stem cells extensively used for studies of cell differentiation. Although retinoic acid (RA) is a powerful inducer of neurogenesis in EC cells, it is not clear what specific neuronal subtypes are generated and whether different RAR isotypes may contribute to such neuronal diversification. Here we show that RA treatment during EC embryoid body formation is a highly robust protocol for generation of striatal-like GABAergic neurons which display molecular characteristics of striatopallidal medium spiny neurons (MSNs), including expression of functional dopamine D2 receptor. By using RARα, β and γ selective agonists we show that RARγ is the functionally dominant RAR in mediating RA control of early molecular determinants of MSNs leading to formation of striatopallidal-like neurons. In contrast, activation of RARα is less efficient in generation of this class of neurons, but is essential for differentiation of functional dopaminergic neurons, which may correspond to a subpopulation of inhibitory dopaminergic neurons expressing glutamic acid decarboxylase in vivo.
Collapse
Affiliation(s)
- Anna Podleśny-Drabiniok
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France.,Institut de la Santé et de la Recherche Médicale, U964, Illkirch, France.,Centre National de la Recherche Scientifique, UMR 7104, Illkirch, France.,Université de Strasbourg, Illkirch, France.,Laboratory of Molecular and Cellular Immunology, Department of Tumor Immunology, L. Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Weigla 12, 53-114, Wroclaw, Poland
| | - Joanna Sobska
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France.,Institut de la Santé et de la Recherche Médicale, U964, Illkirch, France.,Centre National de la Recherche Scientifique, UMR 7104, Illkirch, France.,Université de Strasbourg, Illkirch, France.,Advanced Materials Engineering and Modelling Group, Faculty of Chemistry, Wroclaw University of Science and Technology, Wyb. Wyspianskiego 27, 50-370, Wroclaw, Poland
| | - Angel R de Lera
- Departamento de Química Orgánica, Facultade de Química, CINBIO and IIS Galicia Sur, Universidade de Vigo, Vigo, Spain
| | - Krystyna Gołembiowska
- Department of Pharmacology, Institute of Pharmacology, Polish Academy of Sciences, Kraków, Poland
| | - Katarzyna Kamińska
- Department of Pharmacology, Institute of Pharmacology, Polish Academy of Sciences, Kraków, Poland
| | - Pascal Dollé
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France.,Institut de la Santé et de la Recherche Médicale, U964, Illkirch, France.,Centre National de la Recherche Scientifique, UMR 7104, Illkirch, France.,Université de Strasbourg, Illkirch, France
| | - Małgorzata Cebrat
- Laboratory of Molecular and Cellular Immunology, Department of Tumor Immunology, L. Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Weigla 12, 53-114, Wroclaw, Poland
| | - Wojciech Krężel
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France. .,Institut de la Santé et de la Recherche Médicale, U964, Illkirch, France. .,Centre National de la Recherche Scientifique, UMR 7104, Illkirch, France. .,Université de Strasbourg, Illkirch, France.
| |
Collapse
|
13
|
Roles of Retinoic Acid Signaling in Shaping the Neuronal Architecture of the Developing Amphioxus Nervous System. Mol Neurobiol 2017; 55:5210-5229. [PMID: 28875454 DOI: 10.1007/s12035-017-0727-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Accepted: 08/08/2017] [Indexed: 02/01/2023]
Abstract
The morphogen retinoic acid (RA) patterns vertebrate nervous systems and drives neurogenesis, but how these functions evolved remains elusive. Here, we show that RA signaling plays stage- and tissue-specific roles during the formation of neural cell populations with serotonin, dopamine, and GABA neurotransmitter phenotypes in amphioxus, a proxy for the ancestral chordate. Our data suggest that RA signaling restricts the specification of dopamine-containing cells in the ectoderm and of GABA neurons in the neural tube, probably by regulating Hox1 and Hox3 gene expression, respectively. The two Hox genes thus appear to serve distinct functions rather than to participate in a combinatorial Hox code. We were further able to correlate the RA signaling-dependent mispatterning of hindbrain GABA neurons with concomitant motor impairments. Taken together, these data provide new insights into how RA signaling and Hox genes contribute to nervous system as well as to motor control development in amphioxus and hence shed light on the evolution of these functions within vertebrates.
Collapse
|
14
|
Kasim M, Heß V, Scholz H, Persson PB, Fähling M. Achaete-Scute Homolog 1 Expression Controls Cellular Differentiation of Neuroblastoma. Front Mol Neurosci 2016; 9:156. [PMID: 28066180 PMCID: PMC5174122 DOI: 10.3389/fnmol.2016.00156] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Accepted: 12/07/2016] [Indexed: 11/19/2022] Open
Abstract
Neuroblastoma, the major cause of infant cancer deaths, results from fast proliferation of undifferentiated neuroblasts. Treatment of high-risk neuroblastoma includes differentiation with retinoic acid (RA); however, the resistance of many of these tumors to RA-induced differentiation poses a considerable challenge. Human achaete-scute homolog 1 (hASH1) is a proneural basic helix-loop-helix transcription factor essential for neurogenesis and is often upregulated in neuroblastoma. Here, we identified a novel function for hASH1 in regulating the differentiation phenotype of neuroblastoma cells. Global analysis of 986 human neuroblastoma datasets revealed a negative correlation between hASH1 and neuron differentiation that was independent of the N-myc (MYCN) oncogene. Using RA to induce neuron differentiation in two neuroblastoma cell lines displaying high and low levels of hASH1 expression, we confirmed the link between hASH1 expression and the differentiation defective phenotype, which was reversed by silencing hASH1 or by hypoxic preconditioning. We further show that hASH1 suppresses neuronal differentiation by inhibiting transcription at the RA receptor element. Collectively, our data indicate hASH1 to be key for understanding neuroblastoma resistance to differentiation therapy and pave the way for hASH1-targeted therapies for augmenting the response of neuroblastoma to differentiation therapy.
Collapse
Affiliation(s)
- Mumtaz Kasim
- Institut für Vegetative Physiologie, Charité-Universitätsmedizin Berlin Berlin, Germany
| | - Vicky Heß
- Institut für Vegetative Physiologie, Charité-Universitätsmedizin Berlin Berlin, Germany
| | - Holger Scholz
- Institut für Vegetative Physiologie, Charité-Universitätsmedizin Berlin Berlin, Germany
| | - Pontus B Persson
- Institut für Vegetative Physiologie, Charité-Universitätsmedizin Berlin Berlin, Germany
| | - Michael Fähling
- Institut für Vegetative Physiologie, Charité-Universitätsmedizin Berlin Berlin, Germany
| |
Collapse
|
15
|
New Insights Into the Roles of Retinoic Acid Signaling in Nervous System Development and the Establishment of Neurotransmitter Systems. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2016; 330:1-84. [PMID: 28215529 DOI: 10.1016/bs.ircmb.2016.09.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Secreted chiefly from the underlying mesoderm, the morphogen retinoic acid (RA) is well known to contribute to the specification, patterning, and differentiation of neural progenitors in the developing vertebrate nervous system. Furthermore, RA influences the subtype identity and neurotransmitter phenotype of subsets of maturing neurons, although relatively little is known about how these functions are mediated. This review provides a comprehensive overview of the roles played by RA signaling during the formation of the central and peripheral nervous systems of vertebrates and highlights its effects on the differentiation of several neurotransmitter systems. In addition, the evolutionary history of the RA signaling system is discussed, revealing both conserved properties and alternate modes of RA action. It is proposed that comparative approaches should be employed systematically to expand our knowledge of the context-dependent cellular mechanisms controlled by the multifunctional signaling molecule RA.
Collapse
|
16
|
Ware M, Hamdi-Rozé H, Le Friec J, David V, Dupé V. Regulation of downstream neuronal genes by proneural transcription factors during initial neurogenesis in the vertebrate brain. Neural Dev 2016; 11:22. [PMID: 27923395 PMCID: PMC5142277 DOI: 10.1186/s13064-016-0077-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Accepted: 11/29/2016] [Indexed: 01/28/2023] Open
Abstract
BACKGROUND Neurons arise in very specific regions of the neural tube, controlled by components of the Notch signalling pathway, proneural genes, and other bHLH transcription factors. How these specific neuronal areas in the brain are generated during development is just beginning to be elucidated. Notably, the critical role of proneural genes during differentiation of the neuronal populations that give rise to the early axon scaffold in the developing brain is not understood. The regulation of their downstream effectors remains poorly defined. RESULTS This study provides the first overview of the spatiotemporal expression of proneural genes in the neuronal populations of the early axon scaffold in both chick and mouse. Overexpression studies and mutant mice have identified a number of specific neuronal genes that are targets of proneural transcription factors in these neuronal populations. CONCLUSION Together, these results improve our understanding of the molecular mechanisms involved in differentiation of the first neuronal populations in the brain.
Collapse
Affiliation(s)
- Michelle Ware
- Institut de Génétique et Développement de Rennes, Faculté de Médecine, CNRS UMR6290, Université de Rennes 1, IFR140 GFAS, 2 Avenue du Pr. Léon Bernard, 35043, Rennes Cedex, France.,Present address: Department of Physiology, Development and Neuroscience, University of Cambridge, Anatomy Building, Downing Street, CB2 3DY, Cambridge, UK
| | - Houda Hamdi-Rozé
- Institut de Génétique et Développement de Rennes, Faculté de Médecine, CNRS UMR6290, Université de Rennes 1, IFR140 GFAS, 2 Avenue du Pr. Léon Bernard, 35043, Rennes Cedex, France.,Laboratoire de Génétique Moléculaire, CHU Pontchaillou, Rennes Cedex, France
| | - Julien Le Friec
- Institut de Génétique et Développement de Rennes, Faculté de Médecine, CNRS UMR6290, Université de Rennes 1, IFR140 GFAS, 2 Avenue du Pr. Léon Bernard, 35043, Rennes Cedex, France
| | - Véronique David
- Institut de Génétique et Développement de Rennes, Faculté de Médecine, CNRS UMR6290, Université de Rennes 1, IFR140 GFAS, 2 Avenue du Pr. Léon Bernard, 35043, Rennes Cedex, France.,Laboratoire de Génétique Moléculaire, CHU Pontchaillou, Rennes Cedex, France
| | - Valérie Dupé
- Institut de Génétique et Développement de Rennes, Faculté de Médecine, CNRS UMR6290, Université de Rennes 1, IFR140 GFAS, 2 Avenue du Pr. Léon Bernard, 35043, Rennes Cedex, France.
| |
Collapse
|
17
|
Janesick A, Wu SC, Blumberg B. Retinoic acid signaling and neuronal differentiation. Cell Mol Life Sci 2015; 72:1559-76. [PMID: 25558812 PMCID: PMC11113123 DOI: 10.1007/s00018-014-1815-9] [Citation(s) in RCA: 188] [Impact Index Per Article: 20.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2014] [Revised: 12/15/2014] [Accepted: 12/19/2014] [Indexed: 01/13/2023]
Abstract
The identification of neurological symptoms caused by vitamin A deficiency pointed to a critical, early developmental role of vitamin A and its metabolite, retinoic acid (RA). The ability of RA to induce post-mitotic, neural phenotypes in various stem cells, in vitro, served as early evidence that RA is involved in the switch between proliferation and differentiation. In vivo studies have expanded this "opposing signal" model, and the number of primary neurons an embryo develops is now known to depend critically on the levels and spatial distribution of RA. The proneural and neurogenic transcription factors that control the exit of neural progenitors from the cell cycle and allow primary neurons to develop are partly elucidated, but the downstream effectors of RA receptor (RAR) signaling (many of which are putative cell cycle regulators) remain largely unidentified. The molecular mechanisms underlying RA-induced primary neurogenesis in anamniote embryos are starting to be revealed; however, these data have been not been extended to amniote embryos. There is growing evidence that bona fide RARs are found in some mollusks and other invertebrates, but little is known about their necessity or functions in neurogenesis. One normal function of RA is to regulate the cell cycle to halt proliferation, and loss of RA signaling is associated with dedifferentiation and the development of cancer. Identifying the genes and pathways that mediate cell cycle exit downstream of RA will be critical for our understanding of how to target tumor differentiation. Overall, elucidating the molecular details of RAR-regulated neurogenesis will be decisive for developing and understanding neural proliferation-differentiation switches throughout development.
Collapse
Affiliation(s)
- Amanda Janesick
- Department of Developmental and Cell Biology, 2011 Biological Sciences 3, University of California, Irvine, 92697-2300 USA
| | - Stephanie Cherie Wu
- Department of Developmental and Cell Biology, 2011 Biological Sciences 3, University of California, Irvine, 92697-2300 USA
| | - Bruce Blumberg
- Department of Developmental and Cell Biology, 2011 Biological Sciences 3, University of California, Irvine, 92697-2300 USA
- Department of Pharmaceutical Sciences, University of California, Irvine, USA
| |
Collapse
|
18
|
Abstract
The development of the nervous system is critically dependent on the production of functionally diverse neuronal cell types at their correct locations. In the embryonic neural tube, dorsoventral signaling has emerged as a fundamental mechanism for generating neuronal diversity. In contrast, far less is known about how different neuronal cell types are organized along the rostrocaudal axis. In the developing mouse and chick neural tube, hindbrain serotonergic neurons and spinal glutamatergic V3 interneurons are produced from ventral p3 progenitors, which possess a common transcriptional identity but are confined to distinct anterior-posterior territories. In this study, we show that the expression of the transcription factor Neurogenin3 (Neurog3) in the spinal cord controls the correct specification of p3-derived neurons. Gain- and loss-of-function manipulations in the chick and mouse embryo show that Neurog3 switches ventral progenitors from a serotonergic to V3 differentiation program by repressing Ascl1 in spinal p3 progenitors through a mechanism dependent on Hes proteins. In this way, Neurog3 establishes the posterior boundary of the serotonergic system by actively suppressing serotonergic specification in the spinal cord. These results explain how equivalent p3 progenitors within the hindbrain and the spinal cord produce functionally distinct neuron cell types.
Collapse
|
19
|
Repressing notch signaling and expressing TNFα are sufficient to mimic retinal regeneration by inducing Müller glial proliferation to generate committed progenitor cells. J Neurosci 2015; 34:14403-19. [PMID: 25339752 DOI: 10.1523/jneurosci.0498-14.2014] [Citation(s) in RCA: 90] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Retinal damage in teleosts, unlike mammals, induces robust Müller glia-mediated regeneration of lost neurons. We examined whether Notch signaling regulates Müller glia proliferation in the adult zebrafish retina and demonstrated that Notch signaling maintains Müller glia in a quiescent state in the undamaged retina. Repressing Notch signaling, through injection of the γ-secretase inhibitor RO4929097, stimulates a subset of Müller glia to reenter the cell cycle without retinal damage. This RO4929097-induced Müller glia proliferation is mediated by repressing Notch signaling because inducible expression of the Notch Intracellular Domain (NICD) can reverse the effect. This RO4929097-induced proliferation requires Ascl1a expression and Jak1-mediated Stat3 phosphorylation/activation, analogous to the light-damaged retina. Moreover, coinjecting RO4929097 and TNFα, a previously identified damage signal, induced the majority of Müller glia to reenter the cell cycle and produced proliferating neuronal progenitor cells that committed to a neuronal lineage in the undamaged retina. This demonstrates that repressing Notch signaling and activating TNFα signaling are sufficient to induce Müller glia proliferation that generates neuronal progenitor cells that differentiate into retinal neurons, mimicking the responses observed in the regenerating retina.
Collapse
|
20
|
Ratié L, Ware M, Jagline H, David V, Dupé V. Dynamic expression of Notch-dependent neurogenic markers in the chick embryonic nervous system. Front Neuroanat 2014; 8:158. [PMID: 25565981 PMCID: PMC4270182 DOI: 10.3389/fnana.2014.00158] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2014] [Accepted: 12/04/2014] [Indexed: 11/13/2022] Open
Abstract
The establishment of a functional nervous system requires a highly orchestrated process of neural proliferation and differentiation. The evolutionary conserved Notch signaling pathway is a key regulator of this process, regulating basic helix-loop-helix (bHLH) transcriptional repressors and proneural genes. However, little is known about downstream Notch targets and subsequently genes required for neuronal specification. In this report, the expression pattern of Transgelin 3 (Tagln3), Chromogranin A (Chga) and Contactin 2 (Cntn2) was described in detail during early chick embryogenesis. Expression of these genes was largely restricted to the nervous system including the early axon scaffold populations, cranial ganglia and spinal motor neurons. Their temporal and spatial expression were compared with the neuronal markers Nescient Helix-Loop-Helix 1 (Nhlh1), Stathmin 2 (Stmn2) and HuC/D. We show that Tagln3 is an early marker for post-mitotic neurons whereas Chga and Cntn2 are expressed in mature neurons. We demonstrate that inhibition of Notch signaling during spinal cord neurogenesis enhances expression of these markers. This data demonstrates that Tagln3, Chga and Cntn2 represent strong new candidates to contribute to the sequential progression of vertebrate neurogenesis.
Collapse
Affiliation(s)
- Leslie Ratié
- CNRS UMR6290, Faculté de Médecine, Institut de Génétique et Développement de Rennes, Université de Rennes 1 Rennes, France
| | - Michelle Ware
- CNRS UMR6290, Faculté de Médecine, Institut de Génétique et Développement de Rennes, Université de Rennes 1 Rennes, France
| | - Hélène Jagline
- CNRS UMR6290, Faculté de Médecine, Institut de Génétique et Développement de Rennes, Université de Rennes 1 Rennes, France
| | - Véronique David
- CNRS UMR6290, Faculté de Médecine, Institut de Génétique et Développement de Rennes, Université de Rennes 1 Rennes, France ; Laboratoire de Génétique Moléculaire, CHU Pontchaillou Rennes Cedex, France
| | - Valérie Dupé
- CNRS UMR6290, Faculté de Médecine, Institut de Génétique et Développement de Rennes, Université de Rennes 1 Rennes, France
| |
Collapse
|
21
|
Vasconcelos FF, Castro DS. Transcriptional control of vertebrate neurogenesis by the proneural factor Ascl1. Front Cell Neurosci 2014; 8:412. [PMID: 25520623 PMCID: PMC4251449 DOI: 10.3389/fncel.2014.00412] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2014] [Accepted: 11/12/2014] [Indexed: 11/19/2022] Open
Abstract
Proneural transcription factors (TFs) such as Ascl1 function as master regulators of neurogenesis in vertebrates, being both necessary and sufficient for the activation of a full program of neuronal differentiation. Novel insights into the dynamics of Ascl1 expression at the cellular level, combined with the progressive characterization of its transcriptional program, have expanded the classical view of Ascl1 as a differentiation factor in neurogenesis. These advances resulted in a new model, whereby Ascl1 promotes sequentially the proliferation and differentiation of neural/stem progenitor cells. The multiple activities of Ascl1 are associated with the activation of distinct direct targets at progressive stages along the neuronal lineage. How this temporal pattern is established is poorly understood. Two modes of Ascl1 expression recently described (oscillatory vs. sustained) are likely to be of importance, together with additional mechanistic determinants such as the chromatin landscape and other transcriptional pathways. Here we revise these latest findings, and discuss their implications to the gene regulatory functions of Ascl1 during neurogenesis.
Collapse
Affiliation(s)
| | - Diogo S Castro
- Molecular Neurobiology, Instituto Gulbenkian de Ciência Oeiras, Portugal
| |
Collapse
|
22
|
Devanna P, Middelbeek J, Vernes SC. FOXP2 drives neuronal differentiation by interacting with retinoic acid signaling pathways. Front Cell Neurosci 2014; 8:305. [PMID: 25309332 PMCID: PMC4176457 DOI: 10.3389/fncel.2014.00305] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Accepted: 09/10/2014] [Indexed: 11/14/2022] Open
Abstract
FOXP2 was the first gene shown to cause a Mendelian form of speech and language disorder. Although developmentally expressed in many organs, loss of a single copy of FOXP2 leads to a phenotype that is largely restricted to orofacial impairment during articulation and linguistic processing deficits. Why perturbed FOXP2 function affects specific aspects of the developing brain remains elusive. We investigated the role of FOXP2 in neuronal differentiation and found that FOXP2 drives molecular changes consistent with neuronal differentiation in a human model system. We identified a network of FOXP2 regulated genes related to retinoic acid signaling and neuronal differentiation. FOXP2 also produced phenotypic changes associated with neuronal differentiation including increased neurite outgrowth and reduced migration. Crucially, cells expressing FOXP2 displayed increased sensitivity to retinoic acid exposure. This suggests a mechanism by which FOXP2 may be able to increase the cellular differentiation response to environmental retinoic acid cues for specific subsets of neurons in the brain. These data demonstrate that FOXP2 promotes neuronal differentiation by interacting with the retinoic acid signaling pathway and regulates key processes required for normal circuit formation such as neuronal migration and neurite outgrowth. In this way, FOXP2, which is found only in specific subpopulations of neurons in the brain, may drive precise neuronal differentiation patterns and/or control localization and connectivity of these FOXP2 positive cells.
Collapse
Affiliation(s)
- Paolo Devanna
- Language and Genetics Department, Max Planck Institute for Psycholinguistics Nijmegen, Netherlands
| | - Jeroen Middelbeek
- Laboratory of Pediatric Oncology, Radboud Institute for Molecular Life Sciences, Radboud University Nijmegen, Netherlands
| | - Sonja C Vernes
- Language and Genetics Department, Max Planck Institute for Psycholinguistics Nijmegen, Netherlands ; Donders Institute for Brain, Cognition and Behaviour, Radboud University Nijmegen, Netherlands
| |
Collapse
|
23
|
Vue TY, Kim EJ, Parras CM, Guillemot F, Johnson JE. Ascl1 controls the number and distribution of astrocytes and oligodendrocytes in the gray matter and white matter of the spinal cord. Development 2014; 141:3721-31. [PMID: 25249462 DOI: 10.1242/dev.105270] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Glia constitute the majority of cells in the mammalian central nervous system and are crucial for neurological function. However, there is an incomplete understanding of the molecular control of glial cell development. We find that the transcription factor Ascl1 (Mash1), which is best known for its role in neurogenesis, also functions in both astrocyte and oligodendrocyte lineages arising in the mouse spinal cord at late embryonic stages. Clonal fate mapping in vivo reveals heterogeneity in Ascl1-expressing glial progenitors and shows that Ascl1 defines cells that are restricted to either gray matter (GM) or white matter (WM) as astrocytes or oligodendrocytes. Conditional deletion of Ascl1 post-neurogenesis shows that Ascl1 is required during oligodendrogenesis for generating the correct numbers of WM but not GM oligodendrocyte precursor cells, whereas during astrocytogenesis Ascl1 functions in balancing the number of dorsal GM protoplasmic astrocytes with dorsal WM fibrous astrocytes. Thus, in addition to its function in neurogenesis, Ascl1 marks glial progenitors and controls the number and distribution of astrocytes and oligodendrocytes in the GM and WM of the spinal cord.
Collapse
Affiliation(s)
- Tou Yia Vue
- Department of Neuroscience, UT Southwestern Medical Center, Dallas, TX 75390, USA
| | - Euiseok J Kim
- Department of Neuroscience, UT Southwestern Medical Center, Dallas, TX 75390, USA
| | - Carlos M Parras
- Division of Molecular Neurobiology, MRC National Institute for Medical Research, London NW7 1AA, UK
| | - Francois Guillemot
- Division of Molecular Neurobiology, MRC National Institute for Medical Research, London NW7 1AA, UK
| | - Jane E Johnson
- Department of Neuroscience, UT Southwestern Medical Center, Dallas, TX 75390, USA
| |
Collapse
|
24
|
Integration of signals along orthogonal axes of the vertebrate neural tube controls progenitor competence and increases cell diversity. PLoS Biol 2014; 12:e1001907. [PMID: 25026549 PMCID: PMC4098999 DOI: 10.1371/journal.pbio.1001907] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2014] [Accepted: 06/05/2014] [Indexed: 12/21/2022] Open
Abstract
FGF gates competence to generate Floor Plate and Neural Crest in response to Shh and BMP signals by controlling expression of the transcription factor Nkx1.2. A relatively small number of signals are responsible for the variety and pattern of cell types generated in developing embryos. In part this is achieved by exploiting differences in the concentration or duration of signaling to increase cellular diversity. In addition, however, changes in cellular competence—temporal shifts in the response of cells to a signal—contribute to the array of cell types generated. Here we investigate how these two mechanisms are combined in the vertebrate neural tube to increase the range of cell types and deliver spatial control over their location. We provide evidence that FGF signaling emanating from the posterior of the embryo controls a change in competence of neural progenitors to Shh and BMP, the two morphogens that are responsible for patterning the ventral and dorsal regions of the neural tube, respectively. Newly generated neural progenitors are exposed to FGF signaling, and this maintains the expression of the Nk1-class transcription factor Nkx1.2. Ventrally, this acts in combination with the Shh-induced transcription factor FoxA2 to specify floor plate cells and dorsally in combination with BMP signaling to induce neural crest cells. As development progresses, the intersection of FGF with BMP and Shh signals is interrupted by axis elongation, resulting in the loss of Nkx1.2 expression and allowing the induction of ventral and dorsal interneuron progenitors by Shh and BMP signaling to supervene. Hence a similar mechanism increases cell type diversity at both dorsal and ventral poles of the neural tube. Together these data reveal that tissue morphogenesis produces changes in the coincidence of signals acting along orthogonal axes of the neural tube and this is used to define spatial and temporal transitions in the competence of cells to interpret morphogen signaling. During embryonic development different cell types arise at different times and places. This diversity is produced by a relatively small number of signals and depends, at least in part, on changes in the way cells respond to each signal. One example of this so-called change in “competence” is found in the vertebrate spinal cord where a signal, Sonic Hedgehog (Shh), induces a glial cell type known as floor plate (FP) at early developmental times, while the same signal later induces specific types of neurons. Here, we dissected the molecular mechanism underlying the change in competence, and found that another signal, FGF, is involved through its control of the transcription factor Nkx1.2. In embryos, Shh and FGF are produced perpendicular to one another and FP is induced where the two signals intersect. The position of this intersection changes as the embryo elongates and this determines the place and time FP is produced. A similar strategy also appears to apply to another cell type, neural crest. In this case, the intersection of FGF with BMP signal is crucial. Together the data provide new insight into the spatiotemporal control of cell type specification during development of the vertebrate spinal cord.
Collapse
|
25
|
|