1
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Sagha M. Neural induction: New insight into the default model and an extended four-step model in vertebrate embryos. Dev Dyn 2025. [PMID: 40105405 DOI: 10.1002/dvdy.70002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2024] [Revised: 12/25/2024] [Accepted: 01/13/2025] [Indexed: 03/20/2025] Open
Abstract
Neural induction is a process by which naïve ectodermal cells differentiate into neural progenitor cells through the inhibition of BMP signaling, a condition typically considered the "default" state in vertebrate embryos. Studies in vertebrate embryos indicate that active FGF/MAPK signaling reduces BMP signaling to facilitate neural induction. Consequently, I propose that FGF stimulation/BMP inhibition more accurately characterizes the default model. Initially, the neuroectoderm is instructed to differentiate into anterior forebrain tissue, with cranial signals stabilizing this outcome. Subsequently, a gradient of caudalizing signals converts the neuroectodermal cells into posterior midbrain, hindbrain, and spinal cord. Furthermore, at the caudal end of the embryo, neuromesodermal progenitor cells are destined to differentiate into both neural progenitor cells and mesodermal cells, aiding in body extension. In light of these observations, I suggest incorporating an additional step, elongation, into the conventional three-step model of neural induction. This updated model encompasses activation, stabilization, transformation, and elongation.
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Affiliation(s)
- Mohsen Sagha
- Research Laboratory for Embryology and Stem Cells, Department of Anatomical Sciences, School of Medicine, Ardabil University of Medical Sciences, Ardabil, Iran
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2
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Poole RJ, Flames N, Cochella L. Neurogenesis in Caenorhabditis elegans. Genetics 2024; 228:iyae116. [PMID: 39167071 PMCID: PMC11457946 DOI: 10.1093/genetics/iyae116] [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: 05/28/2024] [Accepted: 06/24/2024] [Indexed: 08/23/2024] Open
Abstract
Animals rely on their nervous systems to process sensory inputs, integrate these with internal signals, and produce behavioral outputs. This is enabled by the highly specialized morphologies and functions of neurons. Neuronal cells share multiple structural and physiological features, but they also come in a large diversity of types or classes that give the nervous system its broad range of functions and plasticity. This diversity, first recognized over a century ago, spurred classification efforts based on morphology, function, and molecular criteria. Caenorhabditis elegans, with its precisely mapped nervous system at the anatomical level, an extensive molecular description of most of its neurons, and its genetic amenability, has been a prime model for understanding how neurons develop and diversify at a mechanistic level. Here, we review the gene regulatory mechanisms driving neurogenesis and the diversification of neuron classes and subclasses in C. elegans. We discuss our current understanding of the specification of neuronal progenitors and their differentiation in terms of the transcription factors involved and ensuing changes in gene expression and chromatin landscape. The central theme that has emerged is that the identity of a neuron is defined by modules of gene batteries that are under control of parallel yet interconnected regulatory mechanisms. We focus on how, to achieve these terminal identities, cells integrate information along their developmental lineages. Moreover, we discuss how neurons are diversified postembryonically in a time-, genetic sex-, and activity-dependent manner. Finally, we discuss how the understanding of neuronal development can provide insights into the evolution of neuronal diversity.
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Affiliation(s)
- Richard J Poole
- Department of Cell and Developmental Biology, University College London, London WC1E 6BT, UK
| | - Nuria Flames
- Developmental Neurobiology Unit, Instituto de Biomedicina de Valencia IBV-CSIC, Valencia 46012, Spain
| | - Luisa Cochella
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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3
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Tamada A, Muguruma K. Recapitulation and investigation of human brain development with neural organoids. IBRO Neurosci Rep 2024; 16:106-117. [PMID: 39007085 PMCID: PMC11240300 DOI: 10.1016/j.ibneur.2023.12.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/16/2024] Open
Abstract
Organoids are 3D cultured tissues derived from stem cells that resemble the structure of living organs. Based on the accumulated knowledge of neural development, neural organoids that recapitulate neural tissue have been created by inducing self-organized neural differentiation of stem cells. Neural organoid techniques have been applied to human pluripotent stem cells to differentiate 3D human neural tissues in culture. Various methods have been developed to generate neural tissues of different regions. Currently, neural organoid technology has several significant limitations, which are being overcome in an attempt to create neural organoids that more faithfully recapitulate the living brain. The rapidly advancing neural organoid technology enables the use of living human neural tissue as research material and contributes to our understanding of the development, structure and function of the human nervous system, and is expected to be used to overcome neurological diseases and for regenerative medicine.
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Affiliation(s)
- Atsushi Tamada
- Department of iPS Cell Applied Medicine, Faculty of Medicine, Kansai Medical University, Hirakata, Osaka 573-1010, Japan
| | - Keiko Muguruma
- Department of iPS Cell Applied Medicine, Faculty of Medicine, Kansai Medical University, Hirakata, Osaka 573-1010, Japan
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4
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Manning E, Placzek M. Organizing activities of axial mesoderm. Curr Top Dev Biol 2024; 157:83-123. [PMID: 38556460 DOI: 10.1016/bs.ctdb.2024.02.007] [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] [Indexed: 04/02/2024]
Abstract
For almost a century, developmental biologists have appreciated that the ability of the embryonic organizer to induce and pattern the body plan is intertwined with its differentiation into axial mesoderm. Despite this, we still have a relatively poor understanding of the contribution of axial mesoderm to induction and patterning of different body regions, and the manner in which axial mesoderm-derived information is interpreted in tissues of changing competence. Here, with a particular focus on the nervous system, we review the evidence that axial mesoderm notochord and prechordal mesoderm/mesendoderm act as organizers, discuss how their influence extends through the different axes of the developing organism, and describe how the ability of axial mesoderm to direct morphogenesis impacts on its role as a local organizer.
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Affiliation(s)
- Elizabeth Manning
- School of Biosciences, University of Sheffield, Sheffield, United Kingdom; Bateson Centre, University of Sheffield, Sheffield, United Kingdom
| | - Marysia Placzek
- School of Biosciences, University of Sheffield, Sheffield, United Kingdom; Bateson Centre, University of Sheffield, Sheffield, United Kingdom; Neuroscience Institute, University of Sheffield, Sheffield, United Kingdom.
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5
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Abstract
This article is about how the famous organizer experiment has been perceived since it was first published in 1924. The experiment involves the production of a secondary embryo under the influence of a graft of a dorsal lip from an amphibian gastrula to a host embryo. The early experiments of Spemann and his school gave rise to a view that the whole early amphibian embryo was "indifferent" in terms of determination, except for a special region called "the organizer". This was viewed mainly as an agent of neural induction, also having the ability to generate an anteroposterior body pattern. Early biochemical efforts to isolate a factor emitted by the organizer were not successful but culminated in the definition of "neuralizing (N)" and "mesodermalizing (M)" factors present in a wide variety of animal tissues. By the 1950s this view became crystallized as a "two gradient" model involving the N and M factors, which explained the anteroposterior patterning effect. In the 1970s, the phenomenon of mesoderm induction was characterized as a process occurring before the commencement of gastrulation. Reinvestigation of the organizer effect using lineage labels gave rise to a more precise definition of the sequence of events. Since the 1980s, modern research using the tools of molecular biology, combined with microsurgery, has explained most of the processes involved. The organizer graft should now be seen as an experiment which involves multiple interactions: dorsoventral polarization following fertilization, mesoderm induction, the dorsalizing signal responsible for neuralization and dorsoventral patterning of the mesoderm, and additional factors responsible for anteroposterior patterning.
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Affiliation(s)
- Jonathan Slack
- Department of Life Sciences, University of Bath, Bath, United Kingdom.
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6
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Regionalization of the Early Nervous System. Neurogenetics 2023. [DOI: 10.1007/978-3-031-07793-7_3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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7
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Hongo I, Okamoto H. FGF/MAPK/Ets signaling in Xenopus ectoderm contributes to neural induction and patterning in an autonomous and paracrine manner, respectively. Cells Dev 2022; 170:203769. [DOI: 10.1016/j.cdev.2022.203769] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2021] [Revised: 01/16/2022] [Accepted: 02/15/2022] [Indexed: 10/19/2022]
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8
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Gupta S, Butler SJ. Getting in touch with your senses: Mechanisms specifying sensory interneurons in the dorsal spinal cord. WIREs Mech Dis 2021; 13:e1520. [PMID: 34730293 PMCID: PMC8459260 DOI: 10.1002/wsbm.1520] [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: 11/02/2020] [Revised: 01/10/2021] [Accepted: 01/11/2021] [Indexed: 11/18/2022]
Abstract
The spinal cord is functionally and anatomically divided into ventrally derived motor circuits and dorsally derived somatosensory circuits. Sensory stimuli originating either at the periphery of the body, or internally, are relayed to the dorsal spinal cord where they are processed by distinct classes of sensory dorsal interneurons (dIs). dIs convey sensory information, such as pain, heat or itch, either to the brain, and/or to the motor circuits to initiate the appropriate response. They also regulate the intensity of sensory information and are the major target for the opioid analgesics. While the developmental mechanisms directing ventral and dorsal cell fates have been hypothesized to be similar, more recent research has suggested that dI fates are specified by novel mechanisms. In this review, we will discuss the molecular events that specify dorsal neuronal patterning in the spinal cord, thereby generating diverse dI identities. We will then discuss how this molecular understanding has led to the development of robust stem cell methods to derive multiple spinal cell types, including the dIs, and the implication of these studies for treating spinal cord injuries and neurodegenerative diseases. This article is categorized under: Neurological Diseases > Stem Cells and Development.
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Affiliation(s)
- Sandeep Gupta
- Department of NeurobiologyUniversity of California, Los AngelesLos AngelesCaliforniaUSA
| | - Samantha J. Butler
- Department of NeurobiologyUniversity of California, Los AngelesLos AngelesCaliforniaUSA
- Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell ResearchUniversity of California, Los AngelesLos AngelesCaliforniaUSA
- Intellectual and Developmental Disabilities Research CenterUniversity of California, Los AngelesLos AngelesCaliforniaUSA
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9
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Bahram Sangani N, Gomes AR, Curfs LMG, Reutelingsperger CP. The role of Extracellular Vesicles during CNS development. Prog Neurobiol 2021; 205:102124. [PMID: 34314775 DOI: 10.1016/j.pneurobio.2021.102124] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2020] [Revised: 04/16/2021] [Accepted: 07/20/2021] [Indexed: 12/21/2022]
Abstract
With a diverse set of neuronal and glial cell populations, Central Nervous System (CNS) has one of the most complex structures in the body. Intercellular communication is therefore highly important to coordinate cell-to-cell interactions. Besides electrical and chemical messengers, CNS cells also benefit from another communication route, what is known as extracellular vesicles, to harmonize their interactions. Extracellular Vesicles (EVs) and their subtype exosomes are membranous particles secreted by cells and contain information packaged in the form of biomolecules such as small fragments of DNA, lipids, miRNAs, mRNAs, and proteins. They are able to efficiently drive changes upon their arrival to recipient cells. EVs actively participate in all stages of CNS development by stimulating neural cell proliferation, differentiation, synaptic formation, and mediating reciprocal interactions between neurons and oligodendrocyte for myelination process. The aim of the present review is to enlighten the presence and contribution of EVs at each CNS developmental milestone.
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Affiliation(s)
- Nasim Bahram Sangani
- Department of Biochemistry, Maastricht University, Cardiovascular Research Institute Maastricht, Maastricht, the Netherlands; GKC-Rett Expertise Centre, Maastricht University Medical Centre, Maastricht, the Netherlands.
| | - Ana Rita Gomes
- Department of Bioengineering and IBB - Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001, Lisboa, Portugal; Instituto de Medicina Molecular - João Lobo Antunes, Faculdade de Medicina da Universidade de Lisboa, Portugal.
| | - Leopold M G Curfs
- GKC-Rett Expertise Centre, Maastricht University Medical Centre, Maastricht, the Netherlands.
| | - Chris P Reutelingsperger
- Department of Biochemistry, Maastricht University, Cardiovascular Research Institute Maastricht, Maastricht, the Netherlands; GKC-Rett Expertise Centre, Maastricht University Medical Centre, Maastricht, the Netherlands.
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10
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Comella-Bolla A, Orlandi JG, Miguez A, Straccia M, García-Bravo M, Bombau G, Galofré M, Sanders P, Carrere J, Segovia JC, Blasi J, Allen ND, Alberch J, Soriano J, Canals JM. Human Pluripotent Stem Cell-Derived Neurons Are Functionally Mature In Vitro and Integrate into the Mouse Striatum Following Transplantation. Mol Neurobiol 2020; 57:2766-2798. [PMID: 32356172 PMCID: PMC7253531 DOI: 10.1007/s12035-020-01907-4] [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: 07/13/2019] [Accepted: 03/23/2020] [Indexed: 01/23/2023]
Abstract
Human pluripotent stem cells (hPSCs) are a powerful tool for modelling human development. In recent years, hPSCs have become central in cell-based therapies for neurodegenerative diseases given their potential to replace affected neurons. However, directing hPSCs into specific neuronal types is complex and requires an accurate protocol that mimics endogenous neuronal development. Here we describe step-by-step a fast feeder-free neuronal differentiation protocol to direct hPSCs to mature forebrain neurons in 37 days in vitro (DIV). The protocol is based upon a combination of specific morphogens, trophic and growth factors, ions, neurotransmitters and extracellular matrix elements. A human-induced PSC line (Ctr-Q33) and a human embryonic stem cell line (GEN-Q18) were used to reinforce the potential of the protocol. Neuronal activity was analysed by single-cell calcium imaging. At 8 DIV, we obtained a homogeneous population of hPSC-derived neuroectodermal progenitors which self-arranged in bi-dimensional neural tube-like structures. At 16 DIV, we generated hPSC-derived neural progenitor cells (NPCs) with mostly a subpallial identity along with a subpopulation of pallial NPCs. Terminal in vitro neuronal differentiation was confirmed by the expression of microtubule associated protein 2b (Map 2b) by almost 100% of hPSC-derived neurons and the expression of specific-striatal neuronal markers including GABA, CTIP2 and DARPP-32. HPSC-derived neurons showed mature and functional phenotypes as they expressed synaptic markers, voltage-gated ion channels and neurotransmitter receptors. Neurons displayed diverse spontaneous activity patterns that were classified into three major groups, namely "high", "intermediate" and "low" firing neurons. Finally, transplantation experiments showed that the NPCs survived and differentiated within mouse striatum for at least 3 months. NPCs integrated host environmental cues and differentiated into striatal medium-sized spiny neurons (MSNs), which successfully integrated into the endogenous circuitry without teratoma formation. Altogether, these findings demonstrate the potential of this robust human neuronal differentiation protocol, which will bring new opportunities for the study of human neurodevelopment and neurodegeneration, and will open new avenues in cell-based therapies, pharmacological studies and alternative in vitro toxicology.
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Affiliation(s)
- Andrea Comella-Bolla
- Laboratory of Stem Cells and Regenerative Medicine, Department of Biomedicine, Faculty of Medicine and Health Science, University of Barcelona, Barcelona, Spain
- Production and validation center of advanced therapies (Creatio), Faculty of Medicine and Health Science, University of Barcelona, Barcelona, Spain
- Institute of Neurosciences, University of Barcelona, Barcelona, Spain
- Networked Biomedical Research Centre for Neurodegenerative Disorders, Barcelona, Spain
- August Pi i Sunyer Biomedical Research Institute (IDIBAPS), Barcelona, Spain
| | - Javier G. Orlandi
- Pathophysiology of Neurodegenerative Disease. Laboratory, Department of Biomedicine, Faculty of Medicine and Health Science, University of Barcelona, Barcelona, Spain
- Departament de Física de la Matèria Condensada, University of Barcelona, Barcelona, Spain
- Department of Physics and Astronomy, University of Calgary, Calgary, Canada
| | - Andrés Miguez
- Laboratory of Stem Cells and Regenerative Medicine, Department of Biomedicine, Faculty of Medicine and Health Science, University of Barcelona, Barcelona, Spain
- Production and validation center of advanced therapies (Creatio), Faculty of Medicine and Health Science, University of Barcelona, Barcelona, Spain
- Institute of Neurosciences, University of Barcelona, Barcelona, Spain
- Networked Biomedical Research Centre for Neurodegenerative Disorders, Barcelona, Spain
- August Pi i Sunyer Biomedical Research Institute (IDIBAPS), Barcelona, Spain
| | - Marco Straccia
- Laboratory of Stem Cells and Regenerative Medicine, Department of Biomedicine, Faculty of Medicine and Health Science, University of Barcelona, Barcelona, Spain
- Production and validation center of advanced therapies (Creatio), Faculty of Medicine and Health Science, University of Barcelona, Barcelona, Spain
- Institute of Neurosciences, University of Barcelona, Barcelona, Spain
- Networked Biomedical Research Centre for Neurodegenerative Disorders, Barcelona, Spain
- August Pi i Sunyer Biomedical Research Institute (IDIBAPS), Barcelona, Spain
| | - María García-Bravo
- Differentiation and Cytometry Unit, Division of Hematopoietic Innovative Therapies, Centro de Investigaciones Energéticas Medioambientales y Tecnológicas and Centro de Investigación Biomédica en Red de Enfermedades Raras (CIEMAT/CIBERER), Madrid, Spain
- Advanced Therapies Unit, Instituto de Investigación Sanitaria Fundación Jiménez Díaz (IIS-FJD, UAM), 28040 Madrid, Spain
| | - Georgina Bombau
- Laboratory of Stem Cells and Regenerative Medicine, Department of Biomedicine, Faculty of Medicine and Health Science, University of Barcelona, Barcelona, Spain
- Production and validation center of advanced therapies (Creatio), Faculty of Medicine and Health Science, University of Barcelona, Barcelona, Spain
- Institute of Neurosciences, University of Barcelona, Barcelona, Spain
- Networked Biomedical Research Centre for Neurodegenerative Disorders, Barcelona, Spain
- August Pi i Sunyer Biomedical Research Institute (IDIBAPS), Barcelona, Spain
| | - Mireia Galofré
- Laboratory of Stem Cells and Regenerative Medicine, Department of Biomedicine, Faculty of Medicine and Health Science, University of Barcelona, Barcelona, Spain
- Production and validation center of advanced therapies (Creatio), Faculty of Medicine and Health Science, University of Barcelona, Barcelona, Spain
- Institute of Neurosciences, University of Barcelona, Barcelona, Spain
- Networked Biomedical Research Centre for Neurodegenerative Disorders, Barcelona, Spain
- August Pi i Sunyer Biomedical Research Institute (IDIBAPS), Barcelona, Spain
| | - Phil Sanders
- Laboratory of Stem Cells and Regenerative Medicine, Department of Biomedicine, Faculty of Medicine and Health Science, University of Barcelona, Barcelona, Spain
- Production and validation center of advanced therapies (Creatio), Faculty of Medicine and Health Science, University of Barcelona, Barcelona, Spain
- Institute of Neurosciences, University of Barcelona, Barcelona, Spain
- Networked Biomedical Research Centre for Neurodegenerative Disorders, Barcelona, Spain
- August Pi i Sunyer Biomedical Research Institute (IDIBAPS), Barcelona, Spain
| | - Jordi Carrere
- Laboratory of Stem Cells and Regenerative Medicine, Department of Biomedicine, Faculty of Medicine and Health Science, University of Barcelona, Barcelona, Spain
- Production and validation center of advanced therapies (Creatio), Faculty of Medicine and Health Science, University of Barcelona, Barcelona, Spain
- Institute of Neurosciences, University of Barcelona, Barcelona, Spain
- Networked Biomedical Research Centre for Neurodegenerative Disorders, Barcelona, Spain
- August Pi i Sunyer Biomedical Research Institute (IDIBAPS), Barcelona, Spain
| | - José Carlos Segovia
- Differentiation and Cytometry Unit, Division of Hematopoietic Innovative Therapies, Centro de Investigaciones Energéticas Medioambientales y Tecnológicas and Centro de Investigación Biomédica en Red de Enfermedades Raras (CIEMAT/CIBERER), Madrid, Spain
- Advanced Therapies Unit, Instituto de Investigación Sanitaria Fundación Jiménez Díaz (IIS-FJD, UAM), 28040 Madrid, Spain
| | - Joan Blasi
- Laboratory of Cellular and Molecular Neurobiology, Department Pathology and Experimental Therapeutics, Faculty of Medicine and Health Science, Biomedical Research Institute of Bellvitge (IDIBELL), University of Barcelona, Barcelona, Spain
| | - Nicholas D. Allen
- Cardiff Repair Group, School of Biosciences and medicine, Cardiff University, Cardiff, Wales UK
| | - Jordi Alberch
- Production and validation center of advanced therapies (Creatio), Faculty of Medicine and Health Science, University of Barcelona, Barcelona, Spain
- Institute of Neurosciences, University of Barcelona, Barcelona, Spain
- Networked Biomedical Research Centre for Neurodegenerative Disorders, Barcelona, Spain
- August Pi i Sunyer Biomedical Research Institute (IDIBAPS), Barcelona, Spain
- Pathophysiology of Neurodegenerative Disease. Laboratory, Department of Biomedicine, Faculty of Medicine and Health Science, University of Barcelona, Barcelona, Spain
| | - Jordi Soriano
- Departament de Física de la Matèria Condensada, University of Barcelona, Barcelona, Spain
- Institute of Complex Systems (UBICS), University of Barcelona, Barcelona, Spain
| | - Josep M. Canals
- Laboratory of Stem Cells and Regenerative Medicine, Department of Biomedicine, Faculty of Medicine and Health Science, University of Barcelona, Barcelona, Spain
- Production and validation center of advanced therapies (Creatio), Faculty of Medicine and Health Science, University of Barcelona, Barcelona, Spain
- Institute of Neurosciences, University of Barcelona, Barcelona, Spain
- Networked Biomedical Research Centre for Neurodegenerative Disorders, Barcelona, Spain
- August Pi i Sunyer Biomedical Research Institute (IDIBAPS), Barcelona, Spain
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11
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Prasad MS, Uribe-Querol E, Marquez J, Vadasz S, Yardley N, Shelar PB, Charney RM, García-Castro MI. Blastula stage specification of avian neural crest. Dev Biol 2020; 458:64-74. [PMID: 31610145 PMCID: PMC7050198 DOI: 10.1016/j.ydbio.2019.10.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Revised: 10/09/2019] [Accepted: 10/09/2019] [Indexed: 11/21/2022]
Abstract
Cell fate specification defines the earliest steps towards a distinct cell lineage. Neural crest, a multipotent stem cell population, is thought to be specified from the ectoderm, but its varied contributions defy canons of segregation potential and challenges its embryonic origin. Aiming to resolve this conflict, we have assayed the earliest specification of neural crest using blastula stage chick embryos. Specification assays on isolated chick epiblast explants identify an intermediate region specified towards the neural crest cell fate. Furthermore, low density culture suggests that the specification of intermediate cells towards the neural crest lineage is independent of contact mediated induction and Wnt-ligand induced signaling, but is, however, dependent on transcriptional activity of β-catenin. Finally, we have validated the regional identity of the intermediate region towards the neural crest cell fate using fate map studies. Our results suggest a model of neural crest specification within a restricted epiblast region in blastula stage chick embryos.
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Affiliation(s)
- Maneeshi S Prasad
- Division of Biomedical Sciences, School of Medicine, University of California, Riverside, USA
| | | | | | | | | | - Patrick B Shelar
- Division of Biomedical Sciences, School of Medicine, University of California, Riverside, USA
| | - Rebekah M Charney
- Division of Biomedical Sciences, School of Medicine, University of California, Riverside, USA
| | - Martín I García-Castro
- Division of Biomedical Sciences, School of Medicine, University of California, Riverside, USA.
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12
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Trpc1 as the Missing Link Between the Bmp and Ca 2+ Signalling Pathways During Neural Specification in Amphibians. Sci Rep 2019; 9:16049. [PMID: 31690785 PMCID: PMC6831629 DOI: 10.1038/s41598-019-52556-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Accepted: 10/16/2019] [Indexed: 12/19/2022] Open
Abstract
In amphibians, the inhibition of bone morphogenetic protein (BMP) in the dorsal ectoderm has been proposed to be responsible for the first step of neural specification, called neural induction. We previously demonstrated that in Xenopus laevis embryos, the BMP signalling antagonist, noggin, triggers an influx of Ca2+ through voltage-dependent L-type Ca2+ channels (LTCCs), mainly via CaV1.2, and we showed that this influx constitutes a necessary and sufficient signal for triggering the expression of neural genes. However, the mechanism linking the inhibition of BMP signalling with the activation of LTCCs remained unknown. Here, we demonstrate that the transient receptor potential canonical subfamily member 1, (Trpc1), is an intermediate between BMP receptor type II (BMPRII) and the CaV1.2 channel. We show that noggin induces a physical interaction between BMPRII and Trpc1 channels. This interaction leads to the activation of Trpc1 channels and to an influx of cations, which depolarizes the plasma membrane up to a threshold sufficient to activate Cav1.2. Together, our results demonstrate for the first time that during neural induction, Ca2+ entry through the CaV1.2 channel results from the noggin-induced interaction between Trpc1 and BMPRII.
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13
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Sivaramakrishnan P, Murray JI. Silencing the alternative. eLife 2019; 8:e49635. [PMID: 31386622 PMCID: PMC6684264 DOI: 10.7554/elife.49635] [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: 07/29/2019] [Accepted: 07/29/2019] [Indexed: 11/13/2022] Open
Abstract
The transcription factor ztf-11 promotes neuronal differentiation by repressing other cell fates in the nematode worm C. elegans.
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Affiliation(s)
| | - John Isaac Murray
- Department of GeneticsPerelman School of MedicinePhiladelphiaUnited States
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14
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Shparberg RA, Glover HJ, Morris MB. Modeling Mammalian Commitment to the Neural Lineage Using Embryos and Embryonic Stem Cells. Front Physiol 2019; 10:705. [PMID: 31354503 PMCID: PMC6637848 DOI: 10.3389/fphys.2019.00705] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Accepted: 05/20/2019] [Indexed: 12/21/2022] Open
Abstract
Early mammalian embryogenesis relies on a large range of cellular and molecular mechanisms to guide cell fate. In this highly complex interacting system, molecular circuitry tightly controls emergent properties, including cell differentiation, proliferation, morphology, migration, and communication. These molecular circuits include those responsible for the control of gene and protein expression, as well as metabolism and epigenetics. Due to the complexity of this circuitry and the relative inaccessibility of the mammalian embryo in utero, mammalian neural commitment remains one of the most challenging and poorly understood areas of developmental biology. In order to generate the nervous system, the embryo first produces two pluripotent populations, the inner cell mass and then the primitive ectoderm. The latter is the cellular substrate for gastrulation from which the three multipotent germ layers form. The germ layer definitive ectoderm, in turn, is the substrate for multipotent neurectoderm (neural plate and neural tube) formation, representing the first morphological signs of nervous system development. Subsequent patterning of the neural tube is then responsible for the formation of most of the central and peripheral nervous systems. While a large number of studies have assessed how a competent neurectoderm produces mature neural cells, less is known about the molecular signatures of definitive ectoderm and neurectoderm and the key molecular mechanisms driving their formation. Using pluripotent stem cells as a model, we will discuss the current understanding of how the pluripotent inner cell mass transitions to pluripotent primitive ectoderm and sequentially to the multipotent definitive ectoderm and neurectoderm. We will focus on the integration of cell signaling, gene activation, and epigenetic control that govern these developmental steps, and provide insight into the novel growth factor-like role that specific amino acids, such as L-proline, play in this process.
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Affiliation(s)
| | | | - Michael B. Morris
- Embryonic Stem Cell Laboratory, Discipline of Physiology, School of Medical Sciences, Bosch Institute, University of Sydney, Sydney, NSW, Australia
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15
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Zhou H, Wang L, Zhang C, Hu J, Chen J, Du W, Liu F, Ren W, Wang J, Quan R. Feasibility of repairing full-thickness skin defects by iPSC-derived epithelial stem cells seeded on a human acellular amniotic membrane. Stem Cell Res Ther 2019; 10:155. [PMID: 31151466 PMCID: PMC6545005 DOI: 10.1186/s13287-019-1234-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Revised: 03/20/2019] [Accepted: 04/14/2019] [Indexed: 12/17/2022] Open
Abstract
Background Induced pluripotent stem cells (iPSCs) can generate epithelial stem cells (EpSCs) as seed cells for skin substitutes to repair skin defects. Here, we investigated the effects of a human acellular amniotic membrane (hAAM) combined with iPSC-derived CD200+/ITGA6+ EpSCs as a skin substitute on repairing skin defects in nude mice. Methods Human urinary cells isolated from a healthy donor were reprogrammed into iPSCs and then induced into CD200+/ITGA6+ epithelial stem cells. Immunocytochemistry and RT-PCR were used to examine the characteristics of the induced epithelial stem cells. iPSC-derived EpSCs were cultured on a hAAM, and cytocompatibility of the composite was analyzed by CCK8 assays and scanning electron microscopy. Then, hAAMs combined with iPSC-derived EpSCs were transplanted onto skin defects of mice. The effects of this composite on skin repair were evaluated by immunohistochemistry. Results The results showed that CD200+/ITGA6+ epithelial stem cells induced from iPSCs displayed the phenotypes of hair follicle stem cells. After seeding on the hAAM, iPSC-derived epithelial stem cells had the ability to proliferate. After transplantation, CD200+/ITGA6+ epithelial stem cells on the hAAM promoted the construction of hair follicles and interfollicular epidermis. Conclusions These results indicated that transplantation of a hAAM combined with iPS-derived EpSCs is feasible to reconstruct skin and skin appendages, and may be a substantial reference for iPSC-based therapy for skin defects.
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Affiliation(s)
- Huateng Zhou
- Clinical Medical College, Zhejiang Chinese Medical University, Zhejiang, 310053, Hangzhou, China
| | - Lixiang Wang
- Department of Orthopedic Surgery, Xiaoshan Traditional Chinese Medical Hospital, Zhejiang, 311200, Hangzhou, China
| | - Cui Zhang
- Laboratory of Stem Cells, Institute of Cell Biology, College of Life Sciences, Zhejiang University, Zhejiang, 310058, Hangzhou, China
| | - Jintao Hu
- Clinical Medical College, Zhejiang Chinese Medical University, Zhejiang, 310053, Hangzhou, China
| | - Jianlin Chen
- Laboratory of Stem Cells, Institute of Cell Biology, College of Life Sciences, Zhejiang University, Zhejiang, 310058, Hangzhou, China
| | - Weibin Du
- Department of Orthopedic Surgery, Xiaoshan Traditional Chinese Medical Hospital, Zhejiang, 311200, Hangzhou, China
| | - Fei Liu
- Department of Chinese Medicine Rehabilitation, Xiushan People's Hospital, Xiushan, Chongqing, 409900, China
| | - Weifan Ren
- Clinical Medical College, Zhejiang Chinese Medical University, Zhejiang, 310053, Hangzhou, China
| | - Jinfu Wang
- Laboratory of Stem Cells, Institute of Cell Biology, College of Life Sciences, Zhejiang University, Zhejiang, 310058, Hangzhou, China.
| | - Renfu Quan
- Clinical Medical College, Zhejiang Chinese Medical University, Zhejiang, 310053, Hangzhou, China.
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16
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Soares E, Zhou H. Master regulatory role of p63 in epidermal development and disease. Cell Mol Life Sci 2018; 75:1179-1190. [PMID: 29103147 PMCID: PMC5843667 DOI: 10.1007/s00018-017-2701-z] [Citation(s) in RCA: 125] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 10/16/2017] [Accepted: 10/26/2017] [Indexed: 01/19/2023]
Abstract
The transcription factor p63 is a master regulator of epidermal development. Mutations in p63 give rise to human developmental diseases that often manifest epidermal defects. In this review, we summarize major p63 isoforms identified so far and p63 mutation-associated human diseases that show epidermal defects. We discuss key roles of p63 in epidermal keratinocyte proliferation and differentiation, emphasizing its master regulatory control of the gene expression pattern and epigenetic landscape that define epidermal fate. We subsequently review the essential function of p63 during epidermal commitment and transdifferentiation towards epithelial lineages, highlighting the notion that p63 is the guardian of the epithelial lineage. Finally, we discuss current therapeutic development strategies for p63 mutation-associated diseases. Our review proposes future directions for dissecting p63-controlled mechanisms in normal and diseased epidermal development and for developing therapeutic options.
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Affiliation(s)
- Eduardo Soares
- Department of Molecular Developmental Biology, Faculty of Science, Radboud Institute for Molecular Life Sciences, Radboud University, 274, Postbus 9101, 6500HB, Nijmegen, The Netherlands
- CAPES Foundation, Ministry of Education of Brazil, Brasília, Brazil
| | - Huiqing Zhou
- Department of Molecular Developmental Biology, Faculty of Science, Radboud Institute for Molecular Life Sciences, Radboud University, 274, Postbus 9101, 6500HB, Nijmegen, The Netherlands.
- Department of Human Genetics, Radboud University Medical Center, 855, Postbus 9101, 6500HB, Nijmegen, The Netherlands.
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17
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Neural induction by the node and placode induction by head mesoderm share an initial state resembling neural plate border and ES cells. Proc Natl Acad Sci U S A 2017; 115:355-360. [PMID: 29259119 DOI: 10.1073/pnas.1719674115] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Around the time of gastrulation in higher vertebrate embryos, inductive interactions direct cells to form central nervous system (neural plate) or sensory placodes. Grafts of different tissues into the periphery of a chicken embryo elicit different responses: Hensen's node induces a neural plate whereas the head mesoderm induces placodes. How different are these processes? Transcriptome analysis in time course reveals that both processes start by induction of a common set of genes, which later diverge. These genes are remarkably similar to those induced by an extraembryonic tissue, the hypoblast, and are normally expressed in the pregastrulation stage epiblast. Explants of this epiblast grown in the absence of further signals develop as neural plate border derivatives and eventually express lens markers. We designate this state as "preborder"; its transcriptome resembles embryonic stem cells. Finally, using sequential transplantation experiments, we show that the node, head mesoderm, and hypoblast are interchangeable to begin any of these inductions while the final outcome depends on the tissue emitting the later signals.
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18
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Juan AH, Wang S, Ko KD, Zare H, Tsai PF, Feng X, Vivanco KO, Ascoli AM, Gutierrez-Cruz G, Krebs J, Sidoli S, Knight AL, Pedersen RA, Garcia BA, Casellas R, Zou J, Sartorelli V. Roles of H3K27me2 and H3K27me3 Examined during Fate Specification of Embryonic Stem Cells. Cell Rep 2017; 17:1369-1382. [PMID: 27783950 DOI: 10.1016/j.celrep.2016.09.087] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Revised: 09/07/2016] [Accepted: 09/26/2016] [Indexed: 10/20/2022] Open
Abstract
The polycomb repressive complex 2 (PRC2) methylates lysine 27 of histone H3 (H3K27) through its catalytic subunit Ezh2. PRC2-mediated di- and tri-methylation (H3K27me2/H3K27me3) have been interchangeably associated with gene repression. However, it remains unclear whether these two degrees of H3K27 methylation have different functions. In this study, we have generated isogenic mouse embryonic stem cells (ESCs) with a modified H3K27me2/H3K27me3 ratio. Our findings document dynamic developmental control in the genomic distribution of H3K27me2 and H3K27me3 at regulatory regions in ESCs. They also reveal that modifying the ratio of H3K27me2 and H3K27me3 is sufficient for the acquisition and repression of defined cell lineage transcriptional programs and phenotypes and influences induction of the ESC ground state.
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Affiliation(s)
- Aster H Juan
- Laboratory of Muscle Stem Cells and Gene Regulation, National Institute of Arthritis, Musculoskeletal and Skin Diseases (NIAMS), National Institutes of Health, Bethesda, MD 20892, USA.
| | - Stan Wang
- Laboratory of Muscle Stem Cells and Gene Regulation, National Institute of Arthritis, Musculoskeletal and Skin Diseases (NIAMS), National Institutes of Health, Bethesda, MD 20892, USA; Wellcome Trust/Cancer Research UK Gurdon Institute, Tennis Court Road, Cambridge CB2 1QN, UK; Department of Surgery, University of Cambridge, Cambridge CB2 0QQ, UK
| | - Kyung Dae Ko
- Laboratory of Muscle Stem Cells and Gene Regulation, National Institute of Arthritis, Musculoskeletal and Skin Diseases (NIAMS), National Institutes of Health, Bethesda, MD 20892, USA
| | - Hossein Zare
- Laboratory of Muscle Stem Cells and Gene Regulation, National Institute of Arthritis, Musculoskeletal and Skin Diseases (NIAMS), National Institutes of Health, Bethesda, MD 20892, USA
| | - Pei-Fang Tsai
- Laboratory of Muscle Stem Cells and Gene Regulation, National Institute of Arthritis, Musculoskeletal and Skin Diseases (NIAMS), National Institutes of Health, Bethesda, MD 20892, USA
| | - Xuesong Feng
- Laboratory of Muscle Stem Cells and Gene Regulation, National Institute of Arthritis, Musculoskeletal and Skin Diseases (NIAMS), National Institutes of Health, Bethesda, MD 20892, USA
| | - Karinna O Vivanco
- Laboratory of Muscle Stem Cells and Gene Regulation, National Institute of Arthritis, Musculoskeletal and Skin Diseases (NIAMS), National Institutes of Health, Bethesda, MD 20892, USA; Department of Biological Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Anthony M Ascoli
- Laboratory of Muscle Stem Cells and Gene Regulation, National Institute of Arthritis, Musculoskeletal and Skin Diseases (NIAMS), National Institutes of Health, Bethesda, MD 20892, USA
| | - Gustavo Gutierrez-Cruz
- Laboratory of Muscle Stem Cells and Gene Regulation, National Institute of Arthritis, Musculoskeletal and Skin Diseases (NIAMS), National Institutes of Health, Bethesda, MD 20892, USA
| | - Jordan Krebs
- Genomics and Immunity, NIAMS, National Institutes of Health, Bethesda, MD 20892, USA
| | - Simone Sidoli
- Epigenetics Program, Department of Biochemistry and Biophysics, Perlman School of Medicine, University of Pennsylvania, Philadelphia 19104 PA, USA
| | - Adam L Knight
- Synaptic Function Section, The Porter Neuroscience Research Center, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
| | - Roger A Pedersen
- Department of Surgery, University of Cambridge, Cambridge CB2 0QQ, UK; The Anne McLaren Laboratory for Regenerative Medicine, University of Cambridge, Downing Street, Cambridge, CB2 3EH, UK
| | - Benjamin A Garcia
- Epigenetics Program, Department of Biochemistry and Biophysics, Perlman School of Medicine, University of Pennsylvania, Philadelphia 19104 PA, USA
| | - Rafael Casellas
- Genomics and Immunity, NIAMS, National Institutes of Health, Bethesda, MD 20892, USA
| | - Jizhong Zou
- iPSC Core Facility, Center for Molecular Medicine, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Vittorio Sartorelli
- Laboratory of Muscle Stem Cells and Gene Regulation, National Institute of Arthritis, Musculoskeletal and Skin Diseases (NIAMS), National Institutes of Health, Bethesda, MD 20892, USA.
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19
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Fathi A, Eisa-Beygi S, Baharvand H. Signaling Molecules Governing Pluripotency and Early Lineage Commitments in Human Pluripotent Stem Cells. CELL JOURNAL 2017; 19:194-203. [PMID: 28670512 PMCID: PMC5412778 DOI: 10.22074/cellj.2016.3915] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Accepted: 07/15/2016] [Indexed: 11/04/2022]
Abstract
Signaling in pluripotent stem cells is a complex and dynamic process involving multiple mediators, finely tuned to balancing pluripotency and differentiation states. Characterizing and modifying the necessary signaling pathways to attain desired cell types is required for stem-cell applications in various fields of regenerative medicine. These signals may help enhance the differentiation potential of pluripotent cells towards each of the embryonic lineages and enable us to achieve pure in vitro cultures of various cell types. This review provides a timely synthesis of recent advances into how maintenance of pluripotency in hPSCs is regulated by extrinsic cues, such as the fibroblast growth factor (FGF) and ACTIVIN signaling pathways, their interplay with other signaling pathways, namely, wingless- type MMTV integration site family (WNT) and mammalian target of rapamycin (mTOR), and the pathways governing the determination of multiple lineages.
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Affiliation(s)
- Ali Fathi
- Department of Stem Cells and Developmental Biology, Cell Science Research Center, Royan Institute for Stem Cell
Biology and Technology, ACECR, Tehran, Iran
| | - Shahram Eisa-Beygi
- Department of Stem Cells and Developmental Biology, Cell Science Research Center, Royan Institute for Stem Cell
Biology and Technology, ACECR, Tehran, Iran
| | - Hossein Baharvand
- Department of Stem Cells and Developmental Biology, Cell Science Research Center, Royan Institute for Stem Cell
Biology and Technology, ACECR, Tehran, Iran
- Department of Developmental Biology, University of Science and Culture, ACECR, Tehran, Iran
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20
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Cofre J, Abdelhay E. Cancer Is to Embryology as Mutation Is to Genetics: Hypothesis of the Cancer as Embryological Phenomenon. ScientificWorldJournal 2017; 2017:3578090. [PMID: 28553657 PMCID: PMC5434308 DOI: 10.1155/2017/3578090] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Accepted: 03/20/2017] [Indexed: 01/20/2023] Open
Abstract
Despite numerous advances in cell biology, genetics, and developmental biology, cancer origin has been attributed to genetic mechanisms primarily involving mutations. Embryologists have expressed timidly cancer embryological origin with little success in leveraging the discussion that cancer could involve a set of conventional cellular processes used to build the embryo during morphogenesis. Thus, this "cancer process" allows the harmonious and coherent construction of the embryo structural base, and its implementation as the embryonic process involves joint regulation of differentiation, proliferation, cell invasion, and migration, enabling the human being recreation of every generation. On the other hand, "cancer disease" is the representation of an abnormal state of the cell that might happen in the stem cells of an adult person, in which the mechanism for joint gene regulating of differentiation, proliferation, cell invasion, and migration could be reactivated in an entirely inappropriate context.
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Affiliation(s)
- Jaime Cofre
- Laboratório de Embriologia Molecular e Câncer, Universidade Federal de Santa Catarina, Sala 313b, 88040-900 Florianópolis, SC, Brazil
| | - Eliana Abdelhay
- Divisão de Laboratórios do CEMO, Instituto Nacional do Câncer, Rio de Janeiro, RJ, Brazil
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21
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22
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Pirmoazen E, Matin M, Najafzadeh N, Golmohammadi MG, Sagha M. Retinoic acid recapitulates the action of the somites on neural differentiation of the developing caudal neural plate in chick embryo. NEUROCHEM J+ 2015; 9:260-265. [DOI: 10.1134/s1819712415040133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/10/2025]
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23
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Merkle FT, Maroof A, Wataya T, Sasai Y, Studer L, Eggan K, Schier AF. Generation of neuropeptidergic hypothalamic neurons from human pluripotent stem cells. Development 2015; 142:633-43. [PMID: 25670790 DOI: 10.1242/dev.117978] [Citation(s) in RCA: 97] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Hypothalamic neurons orchestrate many essential physiological and behavioral processes via secreted neuropeptides, and are relevant to human diseases such as obesity, narcolepsy and infertility. We report the differentiation of human pluripotent stem cells into many of the major types of neuropeptidergic hypothalamic neurons, including those producing pro-opiolemelanocortin, agouti-related peptide, hypocretin/orexin, melanin-concentrating hormone, oxytocin, arginine vasopressin, corticotropin-releasing hormone (CRH) or thyrotropin-releasing hormone. Hypothalamic neurons can be generated using a 'self-patterning' strategy that yields a broad array of cell types, or via a more reproducible directed differentiation approach. Stem cell-derived human hypothalamic neurons share characteristic morphological properties and gene expression patterns with their counterparts in vivo, and are able to integrate into the mouse brain. These neurons could form the basis of cellular models, chemical screens or cellular therapies to study and treat common human diseases.
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Affiliation(s)
- Florian T Merkle
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA 02138, USA Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA Harvard Stem Cell Institute, Harvard University, Cambridge, MA 02138, USA Stanley Center for Psychiatric Research, Broad Institute of Harvard and MIT, Cambridge, MA 02138, USA
| | - Asif Maroof
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA 02138, USA Harvard Stem Cell Institute, Harvard University, Cambridge, MA 02138, USA Stanley Center for Psychiatric Research, Broad Institute of Harvard and MIT, Cambridge, MA 02138, USA
| | - Takafumi Wataya
- Center for Developmental Biology, RIKEN, Kobe 650-0047, Japan Department of Neurosurgery, Hospital for Sick Children, Toronto ON M5G 1X8, Canada
| | - Yoshiki Sasai
- Center for Developmental Biology, RIKEN, Kobe 650-0047, Japan
| | - Lorenz Studer
- The Center for Stem Cell Biology, Sloan-Kettering Institute for Cancer Research, New York, NY 10065, USA Developmental Biology Program, Sloan-Kettering Institute for Cancer Research, New York, NY 10065, USA
| | - Kevin Eggan
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA 02138, USA Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA Harvard Stem Cell Institute, Harvard University, Cambridge, MA 02138, USA Stanley Center for Psychiatric Research, Broad Institute of Harvard and MIT, Cambridge, MA 02138, USA
| | - Alexander F Schier
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA Harvard Stem Cell Institute, Harvard University, Cambridge, MA 02138, USA
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24
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Turner DA, Hayward PC, Baillie-Johnson P, Rué P, Broome R, Faunes F, Martinez Arias A. Wnt/β-catenin and FGF signalling direct the specification and maintenance of a neuromesodermal axial progenitor in ensembles of mouse embryonic stem cells. Development 2015; 141:4243-53. [PMID: 25371361 PMCID: PMC4302903 DOI: 10.1242/dev.112979] [Citation(s) in RCA: 109] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The development of the central nervous system is known to result from two sequential events. First, an inductive event of the mesoderm on the overlying ectoderm that generates a neural plate that, after rolling into a neural tube, acts as the main source of neural progenitors. Second, the axial regionalization of the neural plate that will result in the specification of neurons with different anteroposterior identities. Although this description of the process applies with ease to amphibians and fish, it is more difficult to confirm in amniote embryos. Here, a specialized population of cells emerges at the end of gastrulation that, under the influence of Wnt and FGF signalling, expands and generates the spinal cord and the paraxial mesoderm. This population is known as the long-term neuromesodermal precursor (NMp). Here, we show that controlled increases of Wnt/β-catenin and FGF signalling during adherent culture differentiation of mouse embryonic stem cells (mESCs) generates a population with many of the properties of the NMp. A single-cell analysis of gene expression within this population reveals signatures that are characteristic of stem cell populations. Furthermore, when this activation is triggered in three-dimensional aggregates of mESCs, the population self-organizes macroscopically and undergoes growth and axial elongation that mimics some of the features of the embryonic spinal cord and paraxial mesoderm. We use both adherent and three-dimensional cultures of mESCs to probe the establishment and maintenance of NMps and their differentiation.
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Affiliation(s)
- David A Turner
- Department of Genetics, University of Cambridge, Cambridge CB2 3EH, UK
| | | | | | - Pau Rué
- Department of Genetics, University of Cambridge, Cambridge CB2 3EH, UK
| | - Rebecca Broome
- Department of Genetics, University of Cambridge, Cambridge CB2 3EH, UK
| | - Fernando Faunes
- Department of Genetics, University of Cambridge, Cambridge CB2 3EH, UK
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25
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Bhinge A, Poschmann J, Namboori SC, Tian X, Jia Hui Loh S, Traczyk A, Prabhakar S, Stanton LW. MiR-135b is a direct PAX6 target and specifies human neuroectoderm by inhibiting TGF-β/BMP signaling. EMBO J 2014; 33:1271-83. [PMID: 24802670 DOI: 10.1002/embj.201387215] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Several transcription factors (TFs) have been implicated in neuroectoderm (NE) development, and recently, the TF PAX6 was shown to be critical for human NE specification. However, microRNA networks regulating human NE development have been poorly documented. We hypothesized that microRNAs activated by PAX6 should promote NE development. Using a genomics approach, we identified PAX6 binding sites and active enhancers genome-wide in an in vitro model of human NE development that was based on neural differentiation of human embryonic stem cells (hESC). PAX6 binding to active enhancers was found in the proximity of several microRNAs, including hsa-miR-135b. MiR-135b was activated during NE development, and ectopic expression of miR-135b in hESC promoted differentiation toward NE. MiR-135b promotes neural conversion by targeting components of the TGF-β and BMP signaling pathways, thereby inhibiting differentiation into alternate developmental lineages. Our results demonstrate a novel TF-miRNA module that is activated during human neuroectoderm development and promotes the irreversible fate specification of human pluripotent cells toward the neural lineage.
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Affiliation(s)
- Akshay Bhinge
- Stem Cell and Developmental Biology, Genome Institute of Singapore, Singapore City, Singapore
| | - Jeremie Poschmann
- Computational and Systems Biology, Genome Institute of Singapore, Singapore City, Singapore
| | - Seema C Namboori
- Stem Cell and Developmental Biology, Genome Institute of Singapore, Singapore City, Singapore
| | - Xianfeng Tian
- Stem Cell and Developmental Biology, Genome Institute of Singapore, Singapore City, Singapore
| | - Sharon Jia Hui Loh
- Stem Cell and Developmental Biology, Genome Institute of Singapore, Singapore City, Singapore
| | - Anna Traczyk
- Stem Cell and Developmental Biology, Genome Institute of Singapore, Singapore City, Singapore
| | - Shyam Prabhakar
- Computational and Systems Biology, Genome Institute of Singapore, Singapore City, Singapore
| | - Lawrence W Stanton
- Stem Cell and Developmental Biology, Genome Institute of Singapore, Singapore City, Singapore Department of Biological Sciences, National University of Singapore, Singapore City, Singapore School of Biological Sciences Nanyang Technological University, Singapore City, Singapore
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26
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Generic oscillation patterns of the developing systems and their role in the origin and evolution of ontogeny. Biosystems 2014; 123:37-53. [PMID: 24769154 DOI: 10.1016/j.biosystems.2014.04.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2014] [Revised: 04/13/2014] [Accepted: 04/14/2014] [Indexed: 11/24/2022]
Abstract
The role of generic oscillation patterns in embryonic development on a macroscopic scale is discussed in terms of active shell model. These self-oscillations include periodic changes in both the mean shape of the shell surface and its spatial variance. They lead to origination of a universal oscillatory contour in the form of a non-linear dependence of the average rudiment's curvature upon the curvature variance. The alternation of high and low levels of the variance makes it possible to pursue the developmental dynamics irrespective to the spatiotemporal order of development and characters subject to selection and genetic control. Spatially homogeneous and heterogeneous states can alternate in both time and space being the parametric modifications of the same self-organization dynamics, which is a precondition of transforming of the oscillations into spatial differences between the parts of the embryo and then into successive stages of their formation. This process can be explained as a "retrograde developmental evolution", which means the late evolutionary appearance of the earlier developmental stages. The developing system progressively retreats from the initial self-organization threshold replacing the self-oscillatory dynamics by a linear succession of stages in which the earlier developmental stages appear in the evolution after the later ones. It follows that ontogeny is neither the cause, nor the effect of phylogeny: the phenotype development can be subject to directional change under the constancy of the phenotype itself and, vice versa, the developmental evolution can generate new phenotypes in the absence of the external environmental trends of their evolution.
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27
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Papanayotou C, De Almeida I, Liao P, Oliveira NMM, Lu SQ, Kougioumtzidou E, Zhu L, Shaw A, Sheng G, Streit A, Yu D, Wah Soong T, Stern CD. Calfacilitin is a calcium channel modulator essential for initiation of neural plate development. Nat Commun 2013; 4:1837. [PMID: 23673622 PMCID: PMC3674269 DOI: 10.1038/ncomms2864] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2012] [Accepted: 04/10/2013] [Indexed: 11/09/2022] Open
Abstract
Calcium fluxes have been implicated in the specification of the vertebrate embryonic nervous system for some time, but how these fluxes are regulated and how they relate to the rest of the neural induction cascade is unknown. Here we describe Calfacilitin, a transmembrane calcium channel facilitator that increases calcium flux by generating a larger window current and slowing inactivation of the L-type CaV1.2 channel. Calfacilitin binds to this channel and is co-expressed with it in the embryo. Regulation of intracellular calcium by Calfacilitin is required for expression of the neural plate specifiers Geminin and Sox2 and for neural plate formation. Loss-of-function of Calfacilitin can be rescued by ionomycin, which increases intracellular calcium. Our results elucidate the role of calcium fluxes in early neural development and uncover a new factor in the modulation of calcium signalling.
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Affiliation(s)
- Costis Papanayotou
- Department of Cell and Developmental Biology, University College London, Gower Street (Anatomy Building), London WC1E 6BT, UK.
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28
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Guérout N, Li X, Barnabé-Heider F. Cell fate control in the developing central nervous system. Exp Cell Res 2013; 321:77-83. [PMID: 24140262 DOI: 10.1016/j.yexcr.2013.10.003] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Revised: 10/01/2013] [Accepted: 10/05/2013] [Indexed: 10/26/2022]
Abstract
The principal neural cell types forming the mature central nervous system (CNS) are now understood to be diverse. This cellular subtype diversity originates to a large extent from the specification of the earlier proliferating progenitor populations during development. Here, we review the processes governing the differentiation of a common neuroepithelial cell progenitor pool into mature neurons, astrocytes, oligodendrocytes, ependymal cells and adult stem cells. We focus on studies performed in mice and involving two distinct CNS structures: the spinal cord and the cerebral cortex. Understanding the origin, specification and developmental regulators of neural cells will ultimately impact comprehension and treatments of neurological disorders and diseases.
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Affiliation(s)
- Nicolas Guérout
- Department of Neuroscience, Karolinska Institutet, Stockholm 171 77, Sweden
| | - Xiaofei Li
- Department of Neuroscience, Karolinska Institutet, Stockholm 171 77, Sweden
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29
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Li L, Liu C, Biechele S, Zhu Q, Song L, Lanner F, Jing N, Rossant J. Location of transient ectodermal progenitor potential in mouse development. Development 2013; 140:4533-43. [PMID: 24131634 DOI: 10.1242/dev.092866] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Ectoderm is one of the three classic germ layers in the early mouse embryo, with the capacity to develop into both the central nervous system and epidermis. Because it is a transient phase of development with few molecular markers, the early ectoderm is the least understood germ layer in mouse embryonic development. In this work, we studied the differentiation potential of isolated ectoderm tissue in response to BMP signaling at various developmental stages (E6.5, E7.0 and E7.5), and identified a transient region in the anterior-proximal side of the embryo at E7.0 that possesses the ability to become neural or epidermal ectoderm in response to the absence or presence of BMP4, respectively. Furthermore, we demonstrated that inhibition of Nodal signaling could direct the pluripotent E6.5 epiblast cells towards ectoderm lineages during differentiation in explants in vitro. Our work not only improves our understanding of ectodermal layer development in early embryos, but also provides a framework for regenerative differentiation towards ectodermal tissues.
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Affiliation(s)
- Lingyu Li
- Program in Developmental and Stem Cell Biology, Hospital for Sick Children Research Institute, 555 University Avenue, Toronto, ON M5G 1X8, Canada
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30
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Hegarty SV, O'Keeffe GW, Sullivan AM. BMP-Smad 1/5/8 signalling in the development of the nervous system. Prog Neurobiol 2013; 109:28-41. [PMID: 23891815 DOI: 10.1016/j.pneurobio.2013.07.002] [Citation(s) in RCA: 126] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2012] [Revised: 07/16/2013] [Accepted: 07/16/2013] [Indexed: 02/07/2023]
Abstract
The transcription factors, Smad1, Smad5 and Smad8, are the pivotal intracellular effectors of the bone morphogenetic protein (BMP) family of proteins. BMPs and their receptors are expressed in the nervous system (NS) throughout its development. This review focuses on the actions of Smad 1/5/8 in the developing NS. The mechanisms by which these Smad proteins regulate the induction of the neuroectoderm, the central nervous system (CNS) primordium, and finally the neural crest, which gives rise to the peripheral nervous system (PNS), are reviewed herein. We describe how, following neural tube closure, the most dorsal aspect of the tube becomes a signalling centre for BMPs, which directs the pattern of the development of the dorsal spinal cord (SC), through the action of Smad1, Smad5 and Smad8. The direct effects of Smad 1/5/8 signalling on the development of neuronal and non-neuronal cells from various neural progenitor cell populations are then described. Finally, this review discusses the neurodevelopmental abnormalities associated with the knockdown of Smad 1/5/8.
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Affiliation(s)
- Shane V Hegarty
- Department of Anatomy & Neuroscience, University College Cork, Cork, Ireland
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31
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Midbrain dopaminergic neurons: a review of the molecular circuitry that regulates their development. Dev Biol 2013; 379:123-38. [PMID: 23603197 DOI: 10.1016/j.ydbio.2013.04.014] [Citation(s) in RCA: 131] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2013] [Revised: 03/27/2013] [Accepted: 04/12/2013] [Indexed: 12/21/2022]
Abstract
Dopaminergic (DA) neurons of the ventral midbrain (VM) play vital roles in the regulation of voluntary movement, emotion and reward. They are divided into the A8, A9 and A10 subgroups. The development of the A9 group of DA neurons is an area of intense investigation to aid the generation of these neurons from stem cell sources for cell transplantation approaches to Parkinson's disease (PD). This review discusses the molecular processes that are involved in the identity, specification, maturation, target innervation and survival of VM DA neurons during development. The complex molecular interactions of a number of genetic pathways are outlined, as well as recent advances in the mechanisms that regulate subset identity within the VM DA neuronal pool. A thorough understanding of the cellular and molecular mechanisms involved in the development of VM DA neurons will greatly facilitate the use of cell replacement therapy for the treatment of PD.
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Bielen H, Houart C. BMP signaling protects telencephalic fate by repressing eye identity and its Cxcr4-dependent morphogenesis. Dev Cell 2013; 23:812-22. [PMID: 23079599 DOI: 10.1016/j.devcel.2012.09.006] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2012] [Revised: 08/08/2012] [Accepted: 09/07/2012] [Indexed: 12/22/2022]
Abstract
Depletion of Wnt signaling is a major requirement for the induction of the anterior prosencephalon. However, the molecular events driving the differential regionalization of this area into eye-field and telencephalon fates are still unknown. Here we show that the BMP pathway is active in the anterior neural ectoderm during late blastula to early gastrula stage in zebrafish. Bmp2b mutants and mosaic loss-of-function experiments reveal that BMP acts as a repressor of eye-field fate through inhibition of its key transcription factor Rx3, thereby protecting the future telencephalon from acquiring eye identity. This BMP-driven mechanism initiates the establishment of the telencephalon prior to the involvement of Wnt antagonists from the anterior neural border. Furthermore, we demonstrate that Rx3 and BMP are respectively required to maintain and restrict the chemokine receptor cxcr4a, which in turn contributes to the morphogenetic separation of eye-field and telencephalic cells during early neurulation.
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Affiliation(s)
- Holger Bielen
- Medical Research Council Centre for Developmental Neurobiology, King's College London, London SE1 1UL, UK
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33
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Rudloff S, Kemler R. Differential requirements for β-catenin during mouse development. Development 2012; 139:3711-21. [PMID: 22991437 DOI: 10.1242/dev.085597] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Embryogenesis relies on the precise interplay of signaling cascades to activate tissue-specific differentiation programs. An important player in these morphogenetic processes is β-catenin, which is a central component of adherens junctions and canonical Wnt signaling. Lack of β-catenin is lethal before gastrulation, but mice heterozygous for β-catenin (Ctnnb1) develop as wild type. Here, we confine β-catenin amounts below the heterozygous expression level to study the functional consequences for development. We generate embryonic stem (ES) cells and embryos expressing β-catenin only from the ubiquitously active ROSA26 promoter and thereby limit β-catenin expression to ~12.5% (ROSA26(β/+)) or ~25% (ROSA26(β/β)) of wild-type levels. ROSA26(β/+) is sufficient to maintain ES cell morphology and pluripotent characteristics, but is insufficient to activate canonical target genes upon Wnt stimulation. This Wnt signaling deficiency is incompletely restored in ROSA26(β/β) ES cells. We conclude that even very low β-catenin levels are able to sustain cell adhesion, but not Wnt signaling. During development, ROSA26(β/β) as well as ROSA26(β/+) partially rescues the knockout phenotype, yet proper gastrulation is absent. These embryos differentiate according to the neural default hypothesis, indicating that gastrulation depends on high β-catenin levels. Strikingly, if ROSA26(β/+) or ROSA26(β/β) is first activated after gastrulation, subsequent development correlates with the dosage of β-catenin. Moreover, molecular evidence indicates that the amount of β-catenin controls the induction of specific Wnt target genes. In conclusion, by restricting its expression we determine the level of β-catenin required for adhesion or pluripotency and during different morphogenetic events.
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Affiliation(s)
- Stefan Rudloff
- Max-Planck Institute of Immunobiology and Epigenetics, Department of Molecular Embryology, 79108 Freiburg, Germany.
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Leclerc C, Néant I, Moreau M. The calcium: an early signal that initiates the formation of the nervous system during embryogenesis. Front Mol Neurosci 2012; 5:3. [PMID: 22593733 PMCID: PMC3351002 DOI: 10.3389/fnmol.2012.00064] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2012] [Accepted: 04/25/2012] [Indexed: 01/19/2023] Open
Abstract
The calcium (Ca(2+)) signaling pathways have crucial roles in development from fertilization through differentiation to organogenesis. In the nervous system, Ca(2+) signals are important regulators for various neuronal functions, including formation and maturation of neuronal circuits and long-term memory. However, Ca(2+) signals are also involved in the earliest steps of neurogenesis including neural induction, differentiation of neural progenitors into neurons, and the neuro-glial switch. This review examines when and how Ca(2+) signals are generated during each of these steps with examples taken from in vivo studies in vertebrate embryos and from in vitro assays using embryonic and neural stem cells (NSCs). During the early phases of neurogenesis few investigations have been performed to study the downstream targets of Ca(2+) which posses EF-hand in their structure. This opens an entire field of research. We also discuss the highly specific nature of the Ca(2+) signaling pathway and its interaction with the other signaling pathways involved in early neural development.
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Affiliation(s)
- Catherine Leclerc
- Centre de Biologie du Développement, Université Toulouse III, CNRS UMR 5547Toulouse, France and GDRE n731, “Ca toolkit coded proteins as drug targets in animal and plant cells”
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Xu S, Cheng F, Liang J, Wu W, Zhang J. Maternal xNorrin, a canonical Wnt signaling agonist and TGF-β antagonist, controls early neuroectoderm specification in Xenopus. PLoS Biol 2012; 10:e1001286. [PMID: 22448144 PMCID: PMC3308935 DOI: 10.1371/journal.pbio.1001286] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2011] [Accepted: 02/06/2012] [Indexed: 12/28/2022] Open
Abstract
Xenopus maternal Norrin, which activates Wnt signaling but inhibits TGF-β family molecules, is essential for neuroectoderm formation. Loss of TGF-β inhibition in Norrin may contribute to the development of Norrie disease. Dorsal–ventral specification in the amphibian embryo is controlled by β-catenin, whose activation in all dorsal cells is dependent on maternal Wnt11. However, it remains unknown whether other maternally secreted factors contribute to β-catenin activation in the dorsal ectoderm. Here, we show that maternal Xenopus Norrin (xNorrin) promotes anterior neural tissue formation in ventralized embryos. Conversely, when xNorrin function is inhibited, early canonical Wnt signaling in the dorsal ectoderm and the early expression of the zygotic neural inducers Chordin, Noggin, and Xnr3 are severely suppressed, causing the loss of anterior structures. In addition, xNorrin potently inhibits BMP- and Nodal/Activin-related functions through direct binding to the ligands. Moreover, a subset of Norrin mutants identified in humans with Norrie disease retain Wnt activation but show defective inhibition of Nodal/Activin-related signaling in mesoderm induction, suggesting that this disinhibition causes Norrie disease. Thus, xNorrin is an unusual molecule that acts on two major signaling pathways, Wnt and TGF-β, in opposite ways and is essential for early neuroectoderm specification. A key step during early embryogenesis is the generation of neural precursors, which later form the central nervous system. In vertebrates, this process requires proper dorsal–ventral axis specification, and we know that the canonical Wnt and BMP signaling pathways help pattern the dorsal ectoderm. In this study, we examine other factors that are involved in neuroectoderm development in the frog species Xenopus laevis. We find that maternal Xenopus Norrin (xNorrin) is required for canonical Wnt signaling in the dorsal ectoderm, functions upstream of neural inducers, and is required for neural formation. We also find that xNorrin not only activates Wnt signaling, but also inhibits BMP/Nodal-related signaling. In humans, mutations in Norrin cause Norrie disease. Using Norrin mutants identified in patients with Norrie disease, we find that some Norrin mutants fail to inhibit BMP/Nodal-related signaling (specifically, TGF-β) but retain the ability to activate the Wnt pathway, suggesting that loss of TGF-β inhibition may contribute to Norrie disease development.
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Affiliation(s)
- Suhong Xu
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
- Graduate School of Chinese Academy of Sciences, Beijing, China
| | - Feng Cheng
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
- Graduate School of Chinese Academy of Sciences, Beijing, China
| | - Juan Liang
- Protein Science Laboratory of the Ministry of Education, School of Life Sciences, Tsinghua University, Beijing, China
| | - Wei Wu
- Protein Science Laboratory of the Ministry of Education, School of Life Sciences, Tsinghua University, Beijing, China
| | - Jian Zhang
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
- * E-mail:
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Muguruma K, Sasai Y. In vitro recapitulation of neural development using embryonic stem cells: From neurogenesis to histogenesis. Dev Growth Differ 2012; 54:349-57. [DOI: 10.1111/j.1440-169x.2012.01329.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Mouse ES cells maintained in different pluripotency-promoting conditions differ in their neural differentiation propensity. In Vitro Cell Dev Biol Anim 2012; 48:143-8. [PMID: 22282341 DOI: 10.1007/s11626-012-9486-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2011] [Accepted: 01/08/2012] [Indexed: 10/14/2022]
Abstract
Prior to differentiation, embryonic stem (ES) cells in culture are maintained in a so-called "undifferentiated" state, allowing derivation of multiple downstream cell lineages when induced in a directed manner, which in turn grants these cells their "pluripotent" state. The current work is based on a simple observation that the initial culture condition for maintaining mouse ES cells in an "undifferentiated" state does impact on the differentiation propensity of these cells, in this case to a neuronal fate. We point out the importance in judging the "pluripotency" of a given stem cell culture, as this clearly demonstrated that the "undifferentiated" state of these cells is not necessarily a "pluripotent" state, even for a widely used mouse ES cell line. We partly attribute this difference in the initial value of ES cells to the naïve-to-primed status of pluripotency, which in turn may affect early events of the differentiation in vitro.
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van de Kamp J, Kramann R, Anraths J, Schöler HR, Ko K, Knüchel R, Zenke M, Neuss S, Schneider RK. Epithelial morphogenesis of germline-derived pluripotent stem cells on organotypic skin equivalents in vitro. Differentiation 2011; 83:138-47. [PMID: 22364881 DOI: 10.1016/j.diff.2011.11.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2011] [Revised: 11/15/2011] [Accepted: 11/16/2011] [Indexed: 11/18/2022]
Abstract
For tissue engineering, cultivation of pluripotent stem cells on three-dimensional scaffolds allows the generation of organ-like structures. Previously, we have established an organotypic culture system of skin to induce epidermal differentiation in adult stem cells. Multipotent stem cells are not able to differentiate across germinal boundaries. In contrast, pluripotent stem cells readily differentiate into tissues of all three germ layers. Germline-derived pluripotent stem cells (gPS cells) can be generated by induction of pluripotency in mouse unipotent germline stem cells without the introduction of exogenous transcription factors. In the current study, we analyzed the influence of organotypic culture conditions of skin on the epithelial differentiation of gPS cells in comparison to the well-established HM1 ES cell line. Quantitative RT-PCR data of the pluripotency gene Oct4 showed that gPS cells are characterized by an accelerated Oct4-downregulation compared to HM1 ES cells. When subjected to the organotypic culture conditions of skin, gPS cells formed tubulocystic structures lined by stratified (CK5/6(+), CK14(+), CK8/18(-)) epithelia. HM1 ES cells formed only small tubulocystic structures lined by simple, CK8/18(+) epithelia. BMP-4, an epidermal morphogen, significantly enhanced the expression of epithelial markers in HM1 ES cells, but did not significantly affect the formation of complex (squamous) epithelia in gPS cells. In HM1 ES cells the differentiation into squamous epithelium was only inducible in the presence of mature dermal fibroblasts. Both pluripotent stem cell types spontaneously differentiated into mesodermal, endodermal and into neuroectodermal cells at low frequency, underlining their pluripotent differentiation capacity. Concluding, the organotypic culture conditions of skin induce a multilayered, stratified epithelium in gPS cells, in HM1 ES cells only in the presence of dermal fibroblasts. Thus, our data show that differentiation protocols strongly depend on the stem cell type and have to be modified for each specific stem cell type.
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Affiliation(s)
- Julia van de Kamp
- Institute of Pathology, Medical Faculty, RWTH Aachen University, Aachen, Germany
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Yoon J, Kim JH, Lee OJ, Yu SB, Kim JI, Kim SC, Park JB, Lee JY, Kim J. xCITED2 Induces Neural Genes in Animal Cap Explants of Xenopus Embryos. Exp Neurobiol 2011; 20:123-9. [PMID: 22110370 PMCID: PMC3214773 DOI: 10.5607/en.2011.20.3.123] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2011] [Accepted: 06/17/2011] [Indexed: 11/19/2022] Open
Abstract
Neural tissue is arisen from presumptive ectoderm via inhibition of bone morphogenetic protein (BMP) signaling during Xenopus early development. Previous studies demonstrate that ectopic expression of dominant negative BMP4 receptor (DNBR) produces neural tissue in animal cap explants (AC) and also increases the expression level of various genes involved in neurogenesis. To investigate detail mechanism of neurogenesis in transcriptional level, we analyzed RNAs increased by DNBR using total RNA sequencing analysis and identified several candidate genes. Among them, xCITED2 (Xenopus CBP/p300-interacting transcription activator) was induced 4.6 fold by DNBR and preferentially expressed in neural tissues at tadpole stage. Ectopic expression of xCITED2 induced anterior neural genes without mesoderm induction and reduced BMP downstream genes, an eye specific marker and posterior neural marker. Taken together, these results suggest that xCITED2 may have a role in the differentiation of anterior neural tissue during Xenopus early development.
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Affiliation(s)
- Jaeho Yoon
- Department of Biochemistry, College of Medicine, Hallym University, Chuncheon 200-702, Korea
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40
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Lee HS, Lee SY, Lee H, Hwang YS, Cha SW, Park S, Lee JY, Park JB, Kim S, Park MJ, Kim J. Direct response elements of BMP within the PV.1A promoter are essential for its transcriptional regulation during early Xenopus development. PLoS One 2011; 6:e22621. [PMID: 21857938 PMCID: PMC3153937 DOI: 10.1371/journal.pone.0022621] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2011] [Accepted: 06/26/2011] [Indexed: 01/09/2023] Open
Abstract
Xvent homeobox genes encode transcription factors that repress organizer genes and are essential for dorsoventral specification during early embryogenesis in Xenopus. In contrast to the Xvent-2 gene subfamily, Xvent-1 subfamily members, including PV.1A, have been proposed as indirect targets of Bone Morphogenetic Protein-4 (BMP-4) signaling. Because PV.1A is a critical downstream mediator of, and tightly regulated by, BMP-4 signaling, we hypothesized that its promoter contains a direct BMP-4 response element to effect this transcriptional regulation. We demonstrate that direct regulation by BMP-4 is necessary for transcription of PV.1A: its proximal promoter contains cis-acting binding elements for Smads and Oaz crucial to induction in response to BMP-4 signaling. In addition to these direct cis-acting BMP-4 responsive elements, an indirect Xvent-2 response element and several repressive elements exist in the PV.1A promoter to regulate its transcription. In summary, PV.1A undergoes combinatorial regulation during early Xenopus development as both the direct target of BMP-4 signaling and as the direct and indirect target of positive and negative regulatory factors.
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Affiliation(s)
- Hyun-Shik Lee
- Department of Biochemistry, College of Medicine, Hallym University, ChunCheon, Kangwon-Do, Korea
- School of Life Sciences, College of Natural Sciences, Kyungpook National University, Daegu, Korea
| | - Sung-Young Lee
- Department of Biochemistry, College of Medicine, Hallym University, ChunCheon, Kangwon-Do, Korea
| | - Hyosang Lee
- Department of Anatomy, School of Medicine, Kyungpook National University, Daegu, Korea
| | - Yoo-Seok Hwang
- Department of Anatomy, School of Medicine, Kyungpook National University, Daegu, Korea
| | - Sang-Wook Cha
- Department of Anatomy, School of Medicine, Kyungpook National University, Daegu, Korea
| | - Soochul Park
- Department of Life Science, College of Natural Science, Sookmyung Women's University, Seoul, Korea
| | - Jae-Yong Lee
- Department of Biochemistry, College of Medicine, Hallym University, ChunCheon, Kangwon-Do, Korea
| | - Jae-Bong Park
- Department of Biochemistry, College of Medicine, Hallym University, ChunCheon, Kangwon-Do, Korea
| | - SungChan Kim
- Department of Biochemistry, College of Medicine, Hallym University, ChunCheon, Kangwon-Do, Korea
| | - Mae Ja Park
- Department of Anatomy, School of Medicine, Kyungpook National University, Daegu, Korea
| | - Jaebong Kim
- Department of Biochemistry, College of Medicine, Hallym University, ChunCheon, Kangwon-Do, Korea
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Leclerc C, Néant I, Moreau M. Early neural development in vertebrates is also a matter of calcium. Biochimie 2011; 93:2102-11. [PMID: 21742011 DOI: 10.1016/j.biochi.2011.06.032] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2011] [Accepted: 06/24/2011] [Indexed: 12/19/2022]
Abstract
The calcium (Ca(2+)) signaling pathways have crucial roles in development from fertilization through differentiation to organogenesis. In the nervous system, Ca(2+) signals are important regulators for various neuronal functions, including formation and maturation of neuronal circuits and long-term memory. However, Ca(2+) signals are mainly involved in the earliest steps of nervous system development including neural induction, differentiation of neural progenitors into neurons, and the neuro-glial switch. This review examines when and how Ca(2+) signals are generated during each of these steps with examples taken from in vivo studies in vertebrate embryos and from in vitro assays using embryonic and neural stem cells. Also discussed is the highly specific nature of the Ca(2+) signaling pathway and its interaction with the other signaling pathways involved in early neural development.
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Affiliation(s)
- Catherine Leclerc
- Centre de Biologie du Développement, UMR CNRS 5547 and GDR 2688, Université de Toulouse, 118 route de Narbonne, Toulouse, France.
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42
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Aruga J, Mikoshiba K. Role of BMP, FGF, calcium signaling, and Zic proteins in vertebrate neuroectodermal differentiation. Neurochem Res 2011; 36:1286-92. [PMID: 21336820 PMCID: PMC3111669 DOI: 10.1007/s11064-011-0422-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/04/2011] [Indexed: 12/23/2022]
Abstract
More than a decade has passed since Zic family zinc finger proteins were discovered to be transcription factors controlling neuroectodermal differentiation (neural induction) in Xenopus laevis embryos. Although BMP-signal blocking has been shown to be a major upregulator of Zic genes in neuroectodermal differentiation, recent studies have revealed that FGF signaling and intracellular calcium elevation are also involved in regulating the expression of Zic genes. Different regulatory mechanisms have been found for the Zic1 and Zic3 genes, raising the possibility that functional synergism between them partly accounts for the integration of BMP-signal blocking and FGF signaling in neuroectodermal differentiation. Furthermore, mammalian Zic1 and Zic3 have been found to be neural-cell-fate-inducing and pluripotency-maintaining factors, respectively, leading us to the intriguing question of whether the mechanism underlying amphibian neuroectodermal differentiation is applicable to mammals. Comprehensive understanding of the Zic family genes is therefore essential for the study of the neuroectodermal differentiation and stem cell biology.
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Affiliation(s)
- Jun Aruga
- Laboratory for Behavioral and Developmental Disorders, RIKEN Brain Science Institute, Wako-shi, Saitama, 351-0198, Japan.
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43
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Huang C, Chen J, Zhang T, Zhu Q, Xiang Y, Chen CD, Jing N. The dual histone demethylase KDM7A promotes neural induction in early chick embryos. Dev Dyn 2010; 239:3350-7. [DOI: 10.1002/dvdy.22465] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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44
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Zhang K, Li L, Huang C, Shen C, Tan F, Xia C, Liu P, Rossant J, Jing N. Distinct functions of BMP4 during different stages of mouse ES cell neural commitment. Development 2010; 137:2095-105. [DOI: 10.1242/dev.049494] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Bone morphogenetic protein (BMP) signaling plays a crucial role in maintaining the pluripotency of mouse embryonic stem cells (ESCs) and has negative effects on ESC neural differentiation. However, it remains unclear when and how BMP signaling executes those different functions during neural commitment. Here, we show that a BMP4-sensitive window exists during ESC neural differentiation. Cells at this specific period correspond to the egg cylinder stage epiblast and can be maintained as ESC-derived epiblast stem cells (ESD-EpiSCs), which have the same characteristics as EpiSCs derived from mouse embryos. We propose that ESC neural differentiation occurs in two stages: first from ESCs to ESD-EpiSCs and then from ESD-EpiSCs to neural precursor cells (NPCs). We further show that BMP4 inhibits the conversion of ESCs into ESD-EpiSCs during the first stage, and suppresses ESD-EpiSC neural commitment and promotes non-neural lineage differentiation during the second stage. Mechanistic studies show that BMP4 inhibits FGF/ERK activity at the first stage but not at the second stage; and IDs, as important downstream genes of BMP signaling, partially substitute for BMP4 functions at both stages. We conclude that BMP signaling has distinct functions during different stages of ESC neural commitment.
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Affiliation(s)
- Kejing Zhang
- Laboratory of Molecular Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China
| | - Lingyu Li
- Laboratory of Molecular Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China
| | - Chengyang Huang
- Laboratory of Molecular Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China
| | - Chengyong Shen
- Laboratory of Molecular Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China
| | - Fangzhi Tan
- Laboratory of Molecular Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China
| | - Caihong Xia
- Laboratory of Molecular Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China
| | - Pingyu Liu
- Laboratory of Molecular Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China
| | - Janet Rossant
- Program in Developmental and Stem Cell Biology, Hospital for Sick Children Research Institute, Department of Molecular Genetics, University of Toronto, 555 University Avenue, Toronto, ON M5G 1X8, Canada
| | - Naihe Jing
- Laboratory of Molecular Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China
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45
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Olovnikov AM. How could the program of aging be arranged? RUSS J GEN CHEM+ 2010. [DOI: 10.1134/s1070363210070443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Villegas SN, Canham M, Brickman JM. FGF signalling as a mediator of lineage transitions--evidence from embryonic stem cell differentiation. J Cell Biochem 2010; 110:10-20. [PMID: 20336694 DOI: 10.1002/jcb.22536] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The fibroblast growth factor (FGF) signalling pathway is one of the most ubiquitous in biology. It has diverse roles in development, differentiation and cancer. Embryonic stem (ES) cells are in vitro cell lines capable of differentiating into all the lineages of the conceptus. As such they have the capacity to differentiate into derivatives of all three germ layers and to some extent the extra-embryonic lineages as well. Given the prominent role of FGF signalling in early embryonic development, we explore the role of this pathway in early ES cell differentiation towards the major lineages of the embryo. As early embryonic differentiation is intricately choreographed at the level of morphogenetic movement, adherent ES cell culture affords a unique opportunity to study the basic steps in early lineage specification in the absence of ever shifting complex in vivo microenvironments. Thus recent experiments in ES cell differentiation are able to pinpoint specific FGF dependent lineage transitions that are difficult to resolve in vivo. Here we review the role of FGF signalling in early development alongside the ES cell data and suggest that FGF dependent signalling via phospho-Erk activation maybe a major mediator of transitions in lineage specification.
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Affiliation(s)
- Santiago Nahuel Villegas
- Institute for Stem Cell Research, MRC Centre for Regenerative Medicine, King's Buildings, West Mains Rd., Edinburgh EH9 3JQ, UK
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Avery S, Zafarana G, Gokhale PJ, Andrews PW. The role of SMAD4 in human embryonic stem cell self-renewal and stem cell fate. Stem Cells 2010; 28:863-73. [PMID: 20235236 DOI: 10.1002/stem.409] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Transforming growth factor (TGF)-beta superfamily proteins play a key role in the regulation of human embryonic stem cells (hESCs). Those of the TGFbeta/activin/nodal branch seem to support self-renewal and pluripotency, whereas those of the bone morphogenic protein (BMP) branch induce differentiation. In contrast to this generalization, we found that hESC remained undifferentiated after knockdown of SMAD4 with inducible short hairpin RNA interference, although the knockdown inhibited TGFbeta signaling and rendered the cells nonresponsive to BMP-induced differentiation. Moreover, the rapid differentiation of hESC after pharmacological inhibition of TGFbeta/activin/nodal receptor signaling was restricted after SMAD4 knockdown. These results suggest that TGFbeta/activin/nodal signaling supports the undifferentiated phenotype of hESC by suppressing BMP activity. During long-term culture, SMAD4 knockdown cell populations became less stable and more permissive to neural induction, a situation that was rescued by re-establishment of SMAD4 expression. These results suggest that SMAD4 is not required for maintenance of the undifferentiated state of hESC, but rather to stabilize that state.
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Affiliation(s)
- Stuart Avery
- Department of Biomedical Science, Centre for Stem Cell Biology, University of Sheffield, Western Bank, Sheffield, S10 2TN, United Kingdom.
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Isolation of Early Neurogenesis Genes with XenopuscDNA Microarray. Lab Anim Res 2010. [DOI: 10.5625/lar.2010.26.1.109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Wills AE, Choi VM, Bennett MJ, Khokha MK, Harland RM. BMP antagonists and FGF signaling contribute to different domains of the neural plate in Xenopus. Dev Biol 2009; 337:335-50. [PMID: 19913009 DOI: 10.1016/j.ydbio.2009.11.008] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2009] [Revised: 10/29/2009] [Accepted: 11/03/2009] [Indexed: 01/30/2023]
Abstract
In ectodermal explants from Xenopus embryos, inhibition of BMP signaling is sufficient for neural induction, leading to the idea that neural fate is the default state in the ectoderm. Many of these experiments assayed the action of BMP antagonists on animal caps, which are relatively naïve explants of prospective ectoderm, and different results have led to debate regarding both the mechanism of neural induction and the appropriateness of animal caps as an assay system. Here we address whether BMP antagonists are only able to induce neural fates in pre-patterned explants, and the extent to which neural induction requires FGF signaling. We suggest that some discrepancies in conclusion depend on the interpretations of sox gene expression, which we show not only marks definitive neural tissue, but also tissue that is not yet committed to neural fates. Part of the early sox2 domain requires FGF signaling, but in the absence of organizer signaling, this domain reverts to epidermal fates. We also reinforce the evidence that ectodermal explants are naïve, and that explants that lack any dorsal prepattern are readily neuralized by BMP antagonists, even when FGF signaling is inhibited.
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Affiliation(s)
- Andrea E Wills
- Department of Molecular and Cell Biology and Center for Integrative Genomics, University of California, Berkeley, CA 94720-3200, USA
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