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Antoine JC. Inflammatory sensory neuronopathies. Rev Neurol (Paris) 2024:S0035-3787(24)00455-7. [PMID: 38472032 DOI: 10.1016/j.neurol.2023.12.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Revised: 12/15/2023] [Accepted: 12/22/2023] [Indexed: 03/14/2024]
Abstract
Inflammatory sensory neuronopathies are rare disorders mediated by dysimmune mechanisms targeting sensory neurons in the dorsal root ganglia. They constitute a heterogeneous group of disorders with acute, subacute, or chronic courses, and occur with cancer, systemic autoimmune diseases, notably Sjögren syndrome, and viral infections but a noticeable proportion of them remains isolated. Identifying inflammatory sensory neuronopathies is crucial because they have the potential to be stabilized or even to improve with immunomodulatory or immunosuppressant treatments provided that the treatment is applied at an early stage of the disease, before a definitive degeneration of neurons. Biomarkers, and notably antibodies, are crucial for this early identification, which is the first step to develop therapeutic trials.
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Affiliation(s)
- J-C Antoine
- Department of Neurology, University Hospital of Saint-Etienne, 42055 Saint-Étienne cedex, France.
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2
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Koontz A, Urrutia HA, Bronner ME. Making a head: Neural crest and ectodermal placodes in cranial sensory development. Semin Cell Dev Biol 2023; 138:15-27. [PMID: 35760729 PMCID: PMC10224775 DOI: 10.1016/j.semcdb.2022.06.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 04/11/2022] [Accepted: 06/19/2022] [Indexed: 01/04/2023]
Abstract
During development of the vertebrate sensory system, many important components like the sense organs and cranial sensory ganglia arise within the head and neck. Two progenitor populations, the neural crest, and cranial ectodermal placodes, contribute to these developing vertebrate peripheral sensory structures. The interactions and contributions of these cell populations to the development of the lens, olfactory, otic, pituitary gland, and cranial ganglia are vital for appropriate peripheral nervous system development. Here, we review the origins of both neural crest and placode cells at the neural plate border of the early vertebrate embryo and investigate the molecular and environmental signals that influence specification of different sensory regions. Finally, we discuss the underlying molecular pathways contributing to the complex vertebrate sensory system from an evolutionary perspective, from basal vertebrates to amniotes.
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Affiliation(s)
- Alison Koontz
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Hugo A Urrutia
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Marianne E Bronner
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA.
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3
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Lu Y, Zhang M, Wei Q, Chen Z, Xing G, Yao J, Cao X. Disruption of Gprasp2 down-regulates Hedgehog signaling and leads to apoptosis in auditory cells. Biochem Biophys Res Commun 2021; 574:1-7. [PMID: 34418635 DOI: 10.1016/j.bbrc.2021.08.034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 08/10/2021] [Accepted: 08/11/2021] [Indexed: 11/25/2022]
Abstract
GPRASP2 is implicated in nervous system diseases, tumors and immune inflammation. In our previous study, G protein-coupled receptor associated sorting protein 2 (GPRASP2) was identified as a novel causal gene for X-linked recessive syndromic hearing loss (SHL). However, the role of GPRASP2 in auditory function has not been elucidated. The Gprasp2-knockout (KO) mouse HEI-OC1 auditory cells were constructed using CRISPR/Cas9-mediated gene editing. RNA-sequencing (RNA-seq) was used to investigate the differentially expressed genes (DEGs) and DEGs-enriched signaling pathways, which was verified by Western blot. Flow cytometry assay was used to examine cell apoptosis. The cytological pathology was evaluated by laser scanning confocal microscopy (LSCM) and transmission electron microscopy (TEM). Mitochondrial damage was observed in Gprasp2-KO HEI-OC1 cells. RNA-seq analysis suggested that Gprasp2-KO was implicated in the apoptosis process, which could be mediated by Hedgehog (Hh) signaling pathway. The key molecules in Hh signaling pathway (Smo, Gli1, Gli2) were detected to be down-regulated in Gprasp2-KO HEI-OC1 cells. The differential expression of apoptosis molecules (Bcl2, Bax, Caspase-3/cleaved-Caspase-3) indicated that Gprasp2-KO induced apoptosis in HEI-OC1 cells. The treatment of smoothened agonist (Purmorphamine, PUR) activated the Hh-Gli signaling pathway and reduced apoptosis in Gprasp2-KO HEI-OC1 cells. This study revealed that Gprasp2-disruption inhibited Hh signaling pathway and led to cell apoptosis in HEI-OC1 cells, which might provide the potential molecular mechanism of GPRASP2 mutation associated with human SHL.
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Affiliation(s)
- Yajie Lu
- Department of Medical Genetics, School of Basic Medical Science, Nanjing Medical University, Nanjing, 211166, China; Jiangsu Key Laboratory of Xenotransplantation, Nanjing Medical University, Nanjing, 211166, China
| | - Min Zhang
- Department of Medical Genetics, School of Basic Medical Science, Nanjing Medical University, Nanjing, 211166, China
| | - Qinjun Wei
- Department of Medical Genetics, School of Basic Medical Science, Nanjing Medical University, Nanjing, 211166, China; Jiangsu Key Laboratory of Xenotransplantation, Nanjing Medical University, Nanjing, 211166, China
| | - Zhibin Chen
- Department of Otolaryngology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210009, China
| | - Guangqian Xing
- Department of Otolaryngology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210009, China
| | - Jun Yao
- Department of Medical Genetics, School of Basic Medical Science, Nanjing Medical University, Nanjing, 211166, China; Jiangsu Key Laboratory of Xenotransplantation, Nanjing Medical University, Nanjing, 211166, China.
| | - Xin Cao
- Department of Medical Genetics, School of Basic Medical Science, Nanjing Medical University, Nanjing, 211166, China; Jiangsu Key Laboratory of Xenotransplantation, Nanjing Medical University, Nanjing, 211166, China.
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4
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Summers JA, Schaeffel F, Marcos S, Wu H, Tkatchenko AV. Functional integration of eye tissues and refractive eye development: Mechanisms and pathways. Exp Eye Res 2021; 209:108693. [PMID: 34228967 DOI: 10.1016/j.exer.2021.108693] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Revised: 06/28/2021] [Accepted: 06/30/2021] [Indexed: 12/16/2022]
Abstract
Refractive eye development is a tightly coordinated developmental process. The general layout of the eye and its various components are established during embryonic development, which involves a complex cross-tissue signaling. The eye then undergoes a refinement process during the postnatal emmetropization process, which relies heavily on the integration of environmental and genetic factors and is controlled by an elaborate genetic network. This genetic network encodes a multilayered signaling cascade, which converts visual stimuli into molecular signals that guide the postnatal growth of the eye. The signaling cascade underlying refractive eye development spans across all ocular tissues and comprises multiple signaling pathways. Notably, tissue-tissue interaction plays a key role in both embryonic eye development and postnatal eye emmetropization. Recent advances in eye biometry, physiological optics and systems genetics of refractive error have significantly advanced our understanding of the biological processes involved in refractive eye development and provided a framework for the development of new treatment options for myopia. In this review, we summarize the recent data on the mechanisms and signaling pathways underlying refractive eye development and discuss new evidence suggesting a wide-spread signal integration across different tissues and ocular components involved in visually guided eye growth.
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Affiliation(s)
- Jody A Summers
- Department of Cell Biology, University of Oklahoma Health Science Center, Oklahoma City, OK, USA
| | - Frank Schaeffel
- Section of Neurobiology of the Eye, Ophthalmic Research Institute, University of Tuebingen, Tuebingen, Germany; Myopia Research Group, Institute of Molecular and Clinical Ophthalmology Basel (IOB), Basel, Switzerland
| | - Susana Marcos
- Instituto de Óptica "Daza de Valdés", Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain
| | - Hao Wu
- Department of Ophthalmology, Columbia University, New York, USA
| | - Andrei V Tkatchenko
- Department of Ophthalmology, Columbia University, New York, USA; Department of Pathology and Cell Biology, Columbia University, New York, USA.
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5
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Cell fate decisions during the development of the peripheral nervous system in the vertebrate head. Curr Top Dev Biol 2020; 139:127-167. [PMID: 32450959 DOI: 10.1016/bs.ctdb.2020.04.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Sensory placodes and neural crest cells are among the key cell populations that facilitated the emergence and diversification of vertebrates throughout evolution. Together, they generate the sensory nervous system in the head: both form the cranial sensory ganglia, while placodal cells make major contributions to the sense organs-the eye, ear and olfactory epithelium. Both are instrumental for integrating craniofacial organs and have been key to drive the concentration of sensory structures in the vertebrate head allowing the emergence of active and predatory life forms. Whereas the gene regulatory networks that control neural crest cell development have been studied extensively, the signals and downstream transcriptional events that regulate placode formation and diversity are only beginning to be uncovered. Both cell populations are derived from the embryonic ectoderm, which also generates the central nervous system and the epidermis, and recent evidence suggests that their initial specification involves a common molecular mechanism before definitive neural, neural crest and placodal lineages are established. In this review, we will first discuss the transcriptional networks that pattern the embryonic ectoderm and establish these three cell fates with emphasis on sensory placodes. Second, we will focus on how sensory placode precursors diversify using the specification of otic-epibranchial progenitors and their segregation as an example.
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6
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Wang L, Xie J, Zhang H, Tsang LH, Tsang SL, Braune EB, Lendahl U, Sham MH. Notch signalling regulates epibranchial placode patterning and segregation. Development 2020; 147:dev.183665. [PMID: 31988190 PMCID: PMC7044445 DOI: 10.1242/dev.183665] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Accepted: 01/14/2020] [Indexed: 11/20/2022]
Abstract
Epibranchial placodes are the geniculate, petrosal and nodose placodes that generate parts of cranial nerves VII, IX and X, respectively. How the three spatially separated placodes are derived from the common posterior placodal area is poorly understood. Here, we reveal that the broad posterior placode area is first patterned into a Vgll2+/Irx5+ rostral domain and a Sox2+/Fgf3+/Etv5+ caudal domain relative to the first pharyngeal cleft. This initial rostral and caudal patterning is then sequentially repeated along each pharyngeal cleft for each epibranchial placode. The caudal domains give rise to the neuronal and non-neuronal cells in the placode, whereas the rostral domains are previously unrecognized structures, serving as spacers between the final placodes. Notch signalling regulates the balance between the rostral and caudal domains: high levels of Notch signalling expand the caudal domain at the expense of the rostral domain, whereas loss of Notch signalling produces the converse phenotype. Collectively, these data unravel a new patterning principle for the early phases of epibranchial placode development and a role for Notch signalling in orchestrating epibranchial placode segregation and differentiation.
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Affiliation(s)
- Li Wang
- School of Biomedical Sciences, LKS Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Junjie Xie
- School of Biomedical Sciences, LKS Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Haoran Zhang
- School of Biomedical Sciences, LKS Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Long Hin Tsang
- School of Biomedical Sciences, LKS Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Sze Lan Tsang
- School of Biomedical Sciences, LKS Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Eike-Benjamin Braune
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, SE-171 77, Sweden
| | - Urban Lendahl
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, SE-171 77, Sweden
| | - Mai Har Sham
- School of Biomedical Sciences, LKS Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
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7
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Drake PM, Jourdeuil K, Franz-Odendaal TA. An overlooked placode: Recharacterizing the papillae in the embryonic eye of reptilia. Dev Dyn 2019; 249:164-172. [PMID: 31665553 DOI: 10.1002/dvdy.128] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Revised: 10/10/2019] [Accepted: 10/24/2019] [Indexed: 12/17/2022] Open
Abstract
The papillae in the chicken embryonic eye, described as scleral papillae in the well-known Hamburger and Hamilton (1951) staging table, are one of the key anatomical features used to stage reptilian (including bird) embryos from HH30-36. These papillae are epithelial thickenings of the conjunctiva and are situated above the mesenchymal sclera. Here, we present evidence that the conjunctival papillae, which are required for the induction and patterning of the underlying scleral ossicles, require epithelial pre-patterning and have a placodal stage similar to other placode systems. We also suggest modifications to the Hamburger Hamilton staging criteria that incorporate this change in terminology (from "scleral" to "conjunctival" papillae) and provide a more detailed description of this anatomical feature that includes its placode stage. This enables a more complete and accurate description of chick embryo staging. The acknowledgment of a placode phase, which shares molecular and morphological features with other cutaneous placodes, will direct future research into the early inductive events leading to scleral ossicle formation.
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Affiliation(s)
- Paige M Drake
- Department of Medical Neuroscience, Dalhousie University Faculty of Medicine, Halifax, Nova Scotia, Canada
| | - Karyn Jourdeuil
- Department of Animal and Avian Sciences, University of Maryland at College Park, College Park, Maryland
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8
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Sanchez-Arrones L, Sandonís Á, Cardozo MJ, Bovolenta P. Adenohypophysis placodal precursors exhibit distinctive features within the rostral preplacodal ectoderm. Development 2017; 144:3521-3532. [PMID: 28974641 DOI: 10.1242/dev.149724] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Accepted: 08/14/2017] [Indexed: 11/20/2022]
Abstract
Placodes are discrete thickenings of the vertebrate cranial ectoderm that generate morpho-functionally distinct structures, such as the adenohypophysis, olfactory epithelium and lens. All placodes arise from a horseshoe-shaped preplacodal ectoderm in which the precursors of individual placodes are intermingled. However, fate-map studies indicated that cells positioned at the preplacodal midline give rise to only the adenohypophyseal placode, suggesting a unique organization of these precursors within the preplacode. To test this possibility, we combined embryological and molecular approaches in chick embryos to show that, at gastrula stage, adenohypophyseal precursors are clustered in the median preplacodal ectoderm, largely segregated from those of the adjacent olfactory placode. Median precursors are elongated, densely packed and, at neurula stage, express a molecular signature that distinguishes them from the remaining preplacodal cells. Olfactory placode precursors and midline neural cells can replace ablated adenohypophyseal precursors up to head-fold stage, although with a more plastic organization. We thus propose that adenohypophyseal placode precursors are unique within the preplacodal ectoderm possibly because they originate the only single placode and the only one with an endocrine character.
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Affiliation(s)
- Luisa Sanchez-Arrones
- Centro de Biología Molecular Severo Ochoa, CSIC-UAM, c/ Nicolás Cabrera 1, Madrid 28049, Spain.,CIBER de Enfermedades Raras (CIBERER), c/ Nicolás Cabrera 1, Madrid 28049, Spain
| | - África Sandonís
- Centro de Biología Molecular Severo Ochoa, CSIC-UAM, c/ Nicolás Cabrera 1, Madrid 28049, Spain.,CIBER de Enfermedades Raras (CIBERER), c/ Nicolás Cabrera 1, Madrid 28049, Spain
| | - Marcos Julián Cardozo
- Centro de Biología Molecular Severo Ochoa, CSIC-UAM, c/ Nicolás Cabrera 1, Madrid 28049, Spain.,CIBER de Enfermedades Raras (CIBERER), c/ Nicolás Cabrera 1, Madrid 28049, Spain
| | - Paola Bovolenta
- Centro de Biología Molecular Severo Ochoa, CSIC-UAM, c/ Nicolás Cabrera 1, Madrid 28049, Spain .,CIBER de Enfermedades Raras (CIBERER), c/ Nicolás Cabrera 1, Madrid 28049, Spain
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9
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Cvekl A, Zhang X. Signaling and Gene Regulatory Networks in Mammalian Lens Development. Trends Genet 2017; 33:677-702. [PMID: 28867048 DOI: 10.1016/j.tig.2017.08.001] [Citation(s) in RCA: 120] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 07/27/2017] [Accepted: 08/01/2017] [Indexed: 11/16/2022]
Abstract
Ocular lens development represents an advantageous system in which to study regulatory mechanisms governing cell fate decisions, extracellular signaling, cell and tissue organization, and the underlying gene regulatory networks. Spatiotemporally regulated domains of BMP, FGF, and other signaling molecules in late gastrula-early neurula stage embryos generate the border region between the neural plate and non-neural ectoderm from which multiple cell types, including lens progenitor cells, emerge and undergo initial tissue formation. Extracellular signaling and DNA-binding transcription factors govern lens and optic cup morphogenesis. Pax6, c-Maf, Hsf4, Prox1, Sox1, and a few additional factors regulate the expression of the lens structural proteins, the crystallins. Extensive crosstalk between a diverse array of signaling pathways controls the complexity and order of lens morphogenetic processes and lens transparency.
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Affiliation(s)
- Ales Cvekl
- Departments of Genetics and Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
| | - Xin Zhang
- Departments of Ophthalmology, Pathology and Cell Biology, Columbia University Medical Center, New York, NY 10032, USA.
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10
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Cheung LYM, Davis SW, Brinkmeier ML, Camper SA, Pérez-Millán MI. Regulation of pituitary stem cells by epithelial to mesenchymal transition events and signaling pathways. Mol Cell Endocrinol 2017; 445:14-26. [PMID: 27650955 PMCID: PMC5590650 DOI: 10.1016/j.mce.2016.09.016] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Revised: 09/15/2016] [Accepted: 09/16/2016] [Indexed: 12/11/2022]
Abstract
The anterior pituitary gland is comprised of specialized cell-types that produce and secrete polypeptide hormones in response to hypothalamic input and feedback from target organs. These specialized cells arise from stem cells that express SOX2 and the pituitary transcription factor PROP1, which is necessary to establish the stem cell pool and promote an epithelial to mesenchymal-like transition, releasing progenitors from the niche. The adult anterior pituitary responds to physiological challenge by mobilizing the SOX2-expressing progenitor pool and producing additional hormone-producing cells. Knowledge of the role of signaling pathways and extracellular matrix components in these processes may lead to improvements in the efficiency of differentiation of embryonic stem cells or induced pluripotent stem cells into hormone producing cells in vitro. Advances in our basic understanding of pituitary stem cell regulation and differentiation may lead to improved diagnosis and treatment for patients with hypopituitarism.
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Affiliation(s)
- Leonard Y M Cheung
- Department of Human Genetics, University of Michigan, Ann Arbor, MI 48109-5618, USA.
| | - Shannon W Davis
- Department of Biological Sciences, University of South Carolina, Columbia, SC 29208-0001, USA.
| | - Michelle L Brinkmeier
- Department of Human Genetics, University of Michigan, Ann Arbor, MI 48109-5618, USA.
| | - Sally A Camper
- Department of Human Genetics, University of Michigan, Ann Arbor, MI 48109-5618, USA.
| | - María Inés Pérez-Millán
- Institute of Biomedical Investgations (UBA-CONICET), University of Buenos Aires, Buenos Aires, Argentina.
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11
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Aizawa S, Higaki Y, Dudaui A, Nagasaka M, Takahashi S, Sakata I, Sakai T. Identification of marker genes for pars tuberalis morphogenesis in chick embryo: expression of Cytokine-like 1 and Gap junction protein alpha 5 in pars tuberalis. Cell Tissue Res 2016; 366:721-731. [PMID: 27590887 DOI: 10.1007/s00441-016-2484-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Accepted: 07/22/2016] [Indexed: 10/21/2022]
Abstract
The adenohypophysis is formed from the oral ectoderm and consists of the pars distalis (PD), pars intermedia, and pars tuberalis (PT). The mechanisms of PD development have been extensively studied, and the cellular differentiation of the PD is well understood. However, the morphogenesis and differentiation of the PT are still unclear, and the genes expressed during PT development remain largely unknown. We have explored genes specifically expressed in the PT during embryonic development and analyzed their spatiotemporal expression patterns. Microarray analysis of laser-captured PT and PD tissues obtained from chick embryos on embryonic day 10 (E10.0) has shown high expression of Cytokine-like 1 (CYTL1) and Gap junction protein alpha 5 (GJA5) genes in the PT. Detailed analysis of these spatiotemporal expression patterns during chick embryo development by in situ hybridization has revealed that CYTL1 mRNA first appears in the lateral head ectoderm and ventral head ectoderm at E1.5. The expression of CYTL1 moves into Rathke's pouch at E2.5 and is then localized in the PT primordium where it is continuously expressed until E12.0. GJA5 mRNA is transiently detected in the PT primordium from E6.0 to E12.0, whereas its expression is not detected in the PD during development. Thus, these genes might be involved in the regulation mechanisms of PT development and could be useful markers for PT development.
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Affiliation(s)
- Sayaka Aizawa
- Department of Biology, Graduate School of Natural Science and Technology, Okayama University, 3-1-1, Tsushimanaka, Kita-ku, Okayama, 700-8530, Japan.
| | - Yuriko Higaki
- Area of Reguatory Biology, Division of Life Science, Graduate School of Science and Engineering, Saitama University, 255 Shimo-ohkubo, Sakuraku, Saitama, 338-8570, Japan
| | - Amrita Dudaui
- Area of Reguatory Biology, Division of Life Science, Graduate School of Science and Engineering, Saitama University, 255 Shimo-ohkubo, Sakuraku, Saitama, 338-8570, Japan
| | - Mai Nagasaka
- Area of Reguatory Biology, Division of Life Science, Graduate School of Science and Engineering, Saitama University, 255 Shimo-ohkubo, Sakuraku, Saitama, 338-8570, Japan
| | - Sumio Takahashi
- Department of Biology, Graduate School of Natural Science and Technology, Okayama University, 3-1-1, Tsushimanaka, Kita-ku, Okayama, 700-8530, Japan
| | - Ichiro Sakata
- Area of Reguatory Biology, Division of Life Science, Graduate School of Science and Engineering, Saitama University, 255 Shimo-ohkubo, Sakuraku, Saitama, 338-8570, Japan
| | - Takafumi Sakai
- Area of Reguatory Biology, Division of Life Science, Graduate School of Science and Engineering, Saitama University, 255 Shimo-ohkubo, Sakuraku, Saitama, 338-8570, Japan
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12
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Aguillon R, Blader P, Batut J. Patterning, morphogenesis, and neurogenesis of zebrafish cranial sensory placodes. Methods Cell Biol 2016; 134:33-67. [PMID: 27312490 DOI: 10.1016/bs.mcb.2016.01.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Peripheral sensory organs and ganglia found in the vertebrate head arise during embryonic development from distinct ectodermal thickenings, called cranial sensory placodes (adenohypophyseal, olfactory, lens, trigeminal, epibranchial, and otic). A series of patterning events leads to the establishment of these placodes. Subsequently, these placodes undergo specific morphogenetic movements and cell-type specification in order to shape the final placodal derivatives and to produce differentiated cell types necessary for their function. In this chapter, we will focus on recent studies in the zebrafish that have advanced our understanding of cranial sensory placode development. We will summarize the signaling events and their molecular effectors guiding the formation of the so-called preplacodal region, and the subsequent subdivision of this region along the anteroposterior axis that gives rise to specific placode identities as well as those controlling morphogenesis and neurogenesis. Finally, we will highlight the approaches used in zebrafish that have been established to precisely label cell populations, to follow their development, and/or to characterize cell fates within a specific placode.
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Affiliation(s)
- R Aguillon
- Centre de Biologie du Développement (CBD, UMR5547), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France
| | - P Blader
- Centre de Biologie du Développement (CBD, UMR5547), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France
| | - J Batut
- Centre de Biologie du Développement (CBD, UMR5547), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France
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13
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Edlund RK, Birol O, Groves AK. The role of foxi family transcription factors in the development of the ear and jaw. Curr Top Dev Biol 2015; 111:461-95. [PMID: 25662269 DOI: 10.1016/bs.ctdb.2014.11.014] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The mammalian outer, middle, and inner ears have different embryonic origins and evolved at different times in the vertebrate lineage. The outer ear is derived from first and second branchial arch ectoderm and mesoderm, the middle ear ossicles are derived from neural crest mesenchymal cells that invade the first and second branchial arches, whereas the inner ear and its associated vestibule-acoustic (VIIIth) ganglion are derived from the otic placode. In this chapter, we discuss recent findings in the development of these structures and describe the contributions of members of a Forkhead transcription factor family, the Foxi family to their formation. Foxi transcription factors are critical for formation of the otic placode, survival of the branchial arch neural crest, and developmental remodeling of the branchial arch ectoderm.
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Affiliation(s)
- Renée K Edlund
- Program in Developmental Biology, Baylor College of Medicine, Houston, Texas, USA
| | - Onur Birol
- Program in Developmental Biology, Baylor College of Medicine, Houston, Texas, USA
| | - Andrew K Groves
- Program in Developmental Biology, Baylor College of Medicine, Houston, Texas, USA; Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA; Department of Neuroscience, Baylor College of Medicine, Houston, Texas, USA.
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14
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Lens Development and Crystallin Gene Expression. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2015; 134:129-67. [DOI: 10.1016/bs.pmbts.2015.05.001] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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15
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Cvekl A, Ashery-Padan R. The cellular and molecular mechanisms of vertebrate lens development. Development 2014; 141:4432-47. [PMID: 25406393 PMCID: PMC4302924 DOI: 10.1242/dev.107953] [Citation(s) in RCA: 157] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The ocular lens is a model system for understanding important aspects of embryonic development, such as cell specification and the spatiotemporally controlled formation of a three-dimensional structure. The lens, which is characterized by transparency, refraction and elasticity, is composed of a bulk mass of fiber cells attached to a sheet of lens epithelium. Although lens induction has been studied for over 100 years, recent findings have revealed a myriad of extracellular signaling pathways and gene regulatory networks, integrated and executed by the transcription factor Pax6, that are required for lens formation in vertebrates. This Review summarizes recent progress in the field, emphasizing the interplay between the diverse regulatory mechanisms employed to form lens progenitor and precursor cells and highlighting novel opportunities to fill gaps in our understanding of lens tissue morphogenesis.
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Affiliation(s)
- Aleš Cvekl
- Department of Genetics, Albert Einstein College of Medicine, Bronx, NY 10461, USA Department of Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Ruth Ashery-Padan
- Sackler School of Medicine and Sagol School of Neuroscience, Tel-Aviv University, 69978 Ramat Aviv, Tel Aviv, Israel
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Bhattacharyya S, Bronner ME. Clonal analyses in the anterior pre-placodal region: implications for the early lineage bias of placodal progenitors. THE INTERNATIONAL JOURNAL OF DEVELOPMENTAL BIOLOGY 2014; 57:753-7. [PMID: 24307294 DOI: 10.1387/ijdb.130155mb] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Cranial ectodermal placodes, a vertebrate innovation, contribute to the adenohypophysis and peripheral nervous system of the head, including the paired sense organs (eyes, nose, ears) and sensory ganglia of the Vth, VIIth, IXth and Xth cranial nerves. Fate-maps of groups of cells in amphibians, teleosts and amniotes have demonstrated that all placodes have a common origin in a horseshoe shaped territory, known as the preplacodal region (PPR), which surrounds the presumptive neural plate of the late gastrula/early neurula stage embryo. Given the extensive regional overlap of progenitors for different placodes in the chick embryo, it has been a matter of debate as to whether individual cells in the PPR are truly multipotent progenitors, with regard to placodal identity, or rather are lineage-biased or restricted to a specific placodal type prior to overt differentiation. Utilizing clonal analyses in vivo, we demonstrate here that the anterior PPR comprises some precursors that contribute either to the olfactory or lens placode well before they are spatially segregated or committed to either of these placodal fates. This suggests that lineage bias towards a specific placodal fate may coincide with induction of the PPR.
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17
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Sánchez-Guardado LÓ, Puelles L, Hidalgo-Sánchez M. Fate map of the chicken otic placode. Development 2014; 141:2302-12. [PMID: 24821982 DOI: 10.1242/dev.101667] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The inner ear is an intricate three-dimensional sensory organ that arises from a flat, thickened portion of the ectoderm termed the otic placode. There is evidence that the ontogenetic steps involved in the progressive specification of the highly specialized inner ear of vertebrates involve the concerted actions of diverse patterning signals that originate from nearby tissues, providing positional identity and instructive context. The topology of the prospective inner ear portions at placode stages when such patterning begins has remained largely unknown. The chick-quail model was used to perform a comprehensive fate mapping study of the chick otic placode, shedding light on the precise topological position of each presumptive inner ear component relative to the dorsoventral and anteroposterior axes of the otic placode and, implicitly, to the possible sources of inducing signals. The findings reveal the existence of three dorsoventrally arranged anteroposterior domains from which the endolymphatic system, the maculae and basilar papilla, and the cristae develop. This study provides new bases for the interpretation of earlier and future descriptive and experimental studies that aim to understand the molecular genetic mechanisms involved in otic placode patterning.
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Affiliation(s)
| | - Luis Puelles
- Department of Human Anatomy and Psychobiology, School of Medicine, University of Murcia, 30003 Murcia, Spain
| | - Matías Hidalgo-Sánchez
- Department of Cell Biology, Faculty of Science, University of Extremadura, 06071 Badajoz, Spain
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18
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Saint-Jeannet JP, Moody SA. Establishing the pre-placodal region and breaking it into placodes with distinct identities. Dev Biol 2014; 389:13-27. [PMID: 24576539 DOI: 10.1016/j.ydbio.2014.02.011] [Citation(s) in RCA: 119] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2013] [Revised: 02/13/2014] [Accepted: 02/14/2014] [Indexed: 11/17/2022]
Abstract
Specialized sensory organs in the vertebrate head originate from thickenings in the embryonic ectoderm called cranial sensory placodes. These placodes, as well as the neural crest, arise from a zone of ectoderm that borders the neural plate. This zone separates into a precursor field for the neural crest that lies adjacent to the neural plate, and a precursor field for the placodes, called the pre-placodal region (PPR), that lies lateral to the neural crest. The neural crest domain and the PPR are established in response to signaling events mediated by BMPs, FGFs and Wnts, which differentially activate transcription factors in these territories. In the PPR, members of the Six and Eya families, act in part to repress neural crest specific transcription factors, thus solidifying a placode developmental program. Subsequently, in response to environmental cues the PPR is further subdivided into placodal territories with distinct characteristics, each expressing a specific repertoire of transcription factors that provide the necessary information for their progression to mature sensory organs. In this review we summarize recent advances in the characterization of the signaling molecules and transcriptional effectors that regulate PPR specification and its subdivision into placodal domains with distinct identities.
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Affiliation(s)
- Jean-Pierre Saint-Jeannet
- Department of Basic Science and Craniofacial Biology, New York University, College of Dentistry, 345 East 24th Street, New York City, NY 10010, USA.
| | - Sally A Moody
- Department of Anatomy and Regenerative Biology, The George Washington University, School of Medicine and Health Sciences, 2300 I (eye) Street, NW, Washington, DC 20037, USA.
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19
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Som PM, Streit A, Naidich TP. Illustrated review of the embryology and development of the facial region, part 3: an overview of the molecular interactions responsible for facial development. AJNR Am J Neuroradiol 2014; 35:223-9. [PMID: 23557958 DOI: 10.3174/ajnr.a3453] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
SUMMARY Parts 1 and 2 of this review discussed the complex morphogenesis of the face. However, the molecular processes that drive the morphology of the face were not addressed. Part 3 of this review will present an overview of the genes and their products that have been implicated in the developing face.
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Affiliation(s)
- P M Som
- From the Department of Radiology (P.M.S., T.P.N.), Mount Sinai School of Medicine, New York University, New York, New York
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20
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Setting appropriate boundaries: fate, patterning and competence at the neural plate border. Dev Biol 2013; 389:2-12. [PMID: 24321819 DOI: 10.1016/j.ydbio.2013.11.027] [Citation(s) in RCA: 126] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2013] [Revised: 11/26/2013] [Accepted: 11/27/2013] [Indexed: 11/20/2022]
Abstract
The neural crest and craniofacial placodes are two distinct progenitor populations that arise at the border of the vertebrate neural plate. This border region develops through a series of inductive interactions that begins before gastrulation and progressively divide embryonic ectoderm into neural and non-neural regions, followed by the emergence of neural crest and placodal progenitors. In this review, we describe how a limited repertoire of inductive signals-principally FGFs, Wnts and BMPs-set up domains of transcription factors in the border region which establish these progenitor territories by both cross-inhibitory and cross-autoregulatory interactions. The gradual assembly of different cohorts of transcription factors that results from these interactions is one mechanism to provide the competence to respond to inductive signals in different ways, ultimately generating the neural crest and cranial placodes.
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21
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Mengarelli I, Barberi T. Derivation of multiple cranial tissues and isolation of lens epithelium-like cells from human embryonic stem cells. Stem Cells Transl Med 2013; 2:94-106. [PMID: 23341438 DOI: 10.5966/sctm.2012-0100] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Human embryonic stem cells (hESCs) provide a powerful tool to investigate early events occurring during human embryonic development. In the present study, we induced differentiation of hESCs in conditions that allowed formation of neural and non-neural ectoderm and to a lesser extent mesoderm. These tissues are required for correct specification of the neural plate border, an early embryonic transient structure from which neural crest cells (NCs) and cranial placodes (CPs) originate. Although isolation of CP derivatives from hESCs has not been previously reported, isolation of hESC-derived NC-like cells has been already described. We performed a more detailed analysis of fluorescence-activated cell sorting (FACS)-purified cell populations using the surface antigens previously used to select hESC-derived NC-like cells, p75 and HNK-1, and uncovered their heterogeneous nature. In addition to the NC component, we identified a neural component within these populations using known surface markers, such as CD15 and FORSE1. We have further exploited this information to facilitate the isolation and purification by FACS of a CP derivative, the lens, from differentiating hESCs. Two surface markers expressed on lens cells, c-Met/HGFR and CD44, were used for positive selection of multiple populations with a simultaneous subtraction of the neural/NC component mediated by p75, HNK-1, and CD15. In particular, the c-Met/HGFR allowed early isolation of proliferative lens epithelium-like cells capable of forming lentoid bodies. Isolation of hESC-derived lens cells represents an important step toward the understanding of human lens development and regeneration and the devising of future therapeutic applications.
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Affiliation(s)
- Isabella Mengarelli
- Australian Regenerative Medicine Institute, Monash University, Clayton, Victoria, Australia
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22
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Jidigam VK, Gunhaga L. Development of cranial placodes: insights from studies in chick. Dev Growth Differ 2012; 55:79-95. [PMID: 23278869 DOI: 10.1111/dgd.12027] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2012] [Revised: 11/02/2012] [Accepted: 11/03/2012] [Indexed: 12/19/2022]
Abstract
This review focuses on how research, using chick as a model system, has contributed to our knowledge regarding the development of cranial placodes. This review highlights when and how molecular signaling events regulate early specification of placodal progenitor cells, as well as the development of individual placodes including morphological movements. In addition, we briefly describe various techniques used in chick that are important for studies in cell and developmental biology.
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Affiliation(s)
- Vijay K Jidigam
- Umeå Centre for Molecular Medicine, Umeå University, Umeå, Sweden
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23
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Grocott T, Tambalo M, Streit A. The peripheral sensory nervous system in the vertebrate head: a gene regulatory perspective. Dev Biol 2012; 370:3-23. [PMID: 22790010 DOI: 10.1016/j.ydbio.2012.06.028] [Citation(s) in RCA: 111] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2012] [Revised: 06/28/2012] [Accepted: 06/29/2012] [Indexed: 02/06/2023]
Abstract
In the vertebrate head, crucial parts of the sense organs and sensory ganglia develop from special regions, the cranial placodes. Despite their cellular and functional diversity, they arise from a common field of multipotent progenitors and acquire distinct identity later under the influence of local signalling. Here we present the gene regulatory network that summarises our current understanding of how sensory cells are specified, how they become different from other ectodermal derivatives and how they begin to diversify to generate placodes with different identities. This analysis reveals how sequential activation of sets of transcription factors subdivides the ectoderm over time into smaller domains of progenitors for the central nervous system, neural crest, epidermis and sensory placodes. Within this hierarchy the timing of signalling and developmental history of each cell population is of critical importance to determine the ultimate outcome. A reoccurring theme is that local signals set up broad gene expression domains, which are further refined by mutual repression between different transcription factors. The Six and Eya network lies at the heart of sensory progenitor specification. In a positive feedback loop these factors perpetuate their own expression thus stabilising pre-placodal fate, while simultaneously repressing neural and neural crest specific factors. Downstream of the Six and Eya cassette, Pax genes in combination with other factors begin to impart regional identity to placode progenitors. While our review highlights the wealth of information available, it also points to the lack information on the cis-regulatory mechanisms that control placode specification and of how the repeated use of signalling input is integrated.
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Affiliation(s)
- Timothy Grocott
- Department of Craniofacial Development and Stem Cell Biology, King's College London, Guy's Tower Wing, Floor 27, London SE1 9RT, UK
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24
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Mutual repression between Gbx2 and Otx2 in sensory placodes reveals a general mechanism for ectodermal patterning. Dev Biol 2012; 367:55-65. [PMID: 22564795 PMCID: PMC3384001 DOI: 10.1016/j.ydbio.2012.04.025] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2012] [Revised: 04/13/2012] [Accepted: 04/17/2012] [Indexed: 11/27/2022]
Abstract
In the vertebrate head, central and peripheral components of the sensory nervous system have different embryonic origins, the neural plate and sensory placodes. This raises the question of how they develop in register to form functional sense organs and sensory circuits. Here we show that mutual repression between the homeobox transcription factors Gbx2 and Otx2 patterns the placode territory by influencing regional identity and by segregating inner ear and trigeminal progenitors. Activation of Otx2 targets is necessary for anterior olfactory, lens and trigeminal character, while Gbx2 function is required for the formation of the posterior otic placode. Thus, like in the neural plate antagonistic interaction between Otx2 and Gbx2 establishes positional information thus providing a general mechanism for rostro-caudal patterning of the ectoderm. Our findings support the idea that the Otx/Gbx boundary has an ancient evolutionary origin to which different modules were recruited to specify cells of different fates.
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25
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Abstract
During early vertebrate development, the embryonic ectoderm becomes subdivided into neural, neural plate border (border) and epidermal regions. The nervous system is derived from the neural and border domains which, respectively, give rise to the central and peripheral nervous systems. To better understand the functional nervous system we need to know how individual neurons are specified and connected. Our understanding of the early development of the peripheral nervous system has been lagging compared to knowledge regarding central nervous system and epidermal cell lineage decision. Recent advances have shown when and how the specification of border cells is initiated. One important insight is that border specification is already initiated at blastula stages, and can be molecularly and temporally distinguished from rostrocaudal regionalisation of the border. From findings in several species, it is clear that Wnt, Bone Morphogenetic Protein and Fibroblast Growth Factor signals play important roles during the specification and regionalisation of the border. In this review, we highlight the individual roles of these signals and compare models of border specification, including a new model that describes how temporal coordination and epistatic interactions of extracellular signals result in the specification and regionalisation of border cells.
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Affiliation(s)
- Cédric Patthey
- Umeå Centre for Molecular Medicine, Building 6M, 4th Floor, Umeå University, S-901 87 Umeå, Sweden
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26
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Padanad MS, Bhat N, Guo B, Riley BB. Conditions that influence the response to Fgf during otic placode induction. Dev Biol 2012; 364:1-10. [PMID: 22327005 DOI: 10.1016/j.ydbio.2012.01.022] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2011] [Revised: 01/22/2012] [Accepted: 01/26/2012] [Indexed: 01/04/2023]
Abstract
Despite the vital importance of Fgf for otic induction, previous attempts to study otic induction through Fgf misexpression have yielded widely varying and contradictory results. There are also discrepancies regarding the ability of Fgf to induce otic tissue in ectopic locations, raising questions about the sufficiency of Fgf and the degree to which other local factors enhance or restrict otic potential. Using heat shock-inducible transgenes to misexpress Fgf3 or Fgf8 in zebrafish, we found that the stage, distribution and level of misexpression strongly influence the response to Fgf. Fgf misexpression during gastrulation can inhibit or promote otic development, depending on context, whereas misexpression after gastrulation leads to expansion of otic markers throughout preplacodal ectoderm surrounding the head. Elevated Fgf also expands expression of the putative competence factor Foxi1, which is required for Fgf to expand other otic markers. Misexpression of downstream factors Pax2a or Pax8 also expands otic markers but cannot bypass the requirement for Fgf or Foxi1. Co-misexpression of Pax2/8 with Fgf8 potentiates formation of ectopic otic vesicles expressing a full range of otic markers. These findings document the variables critically affecting the response to Fgf and clarify the roles of foxi1 and pax2/8 in the otic response.
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Affiliation(s)
- Mahesh S Padanad
- Biology Department, Texas A&M University, College Station, TX 77843-3258, USA
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27
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Vandenberg LN, Morrie RD, Adams DS. V-ATPase-dependent ectodermal voltage and pH regionalization are required for craniofacial morphogenesis. Dev Dyn 2011; 240:1889-904. [PMID: 21761475 DOI: 10.1002/dvdy.22685] [Citation(s) in RCA: 101] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Using voltage and pH reporter dyes, we have discovered a never-before-seen regionalization of the Xenopus ectoderm, with cell subpopulations delimited by different membrane voltage and pH. We distinguished three courses of bioelectrical activity. Course I is a wave of hyperpolarization that travels across the gastrula. Course II comprises the appearance of patterns that match shape changes and gene expression domains of the developing face; hyperpolarization marks folding epithelium and both hyperpolarized and depolarized regions overlap domains of head patterning genes. In Course III, localized regions of hyperpolarization form at various positions, expand, and disappear. Inhibiting H(+) -transport by the H(+) -V-ATPase causes abnormalities in: (1) the morphology of craniofacial structures; (2) Course II voltage patterns; and (3) patterns of sox9, pax8, slug, mitf, xfz3, otx2, and pax6. We conclude that this bioelectric signal has a role in development of the face. Thus, it exemplifies an important, under-studied mechanism of developmental regulation.
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Affiliation(s)
- Laura N Vandenberg
- The Tufts Center for Regenerative and Developmental Biology, and Biology Department, Tufts University, Medford, Massachusetts, USA
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28
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Integrin-α5 coordinates assembly of posterior cranial placodes in zebrafish and enhances Fgf-dependent regulation of otic/epibranchial cells. PLoS One 2011; 6:e27778. [PMID: 22164214 PMCID: PMC3229493 DOI: 10.1371/journal.pone.0027778] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2011] [Accepted: 10/25/2011] [Indexed: 12/15/2022] Open
Abstract
Vertebrate sensory organs develop in part from cranial placodes, a series of ectodermal thickenings that coalesce from a common domain of preplacodal ectoderm. Mechanisms coordinating morphogenesis and differentiation of discrete placodes are still poorly understood. We have investigated whether placodal assembly in zebrafish requires Integrin- α5 (itga5), an extracellular matrix receptor initially expressed throughout the preplacodal ectoderm. Morpholino knockdown of itga5 had no detectable effect on anterior placodes (pituitary, nasal and lens), but posterior placodes developed abnormally, resulting in disorganization of trigeminal and epibranchial ganglia and reduction of the otic vesicle. Cell motion analysis in GFP-transgenic embryos showed that cell migration in itga5 morphants was highly erratic and unfocused, impairing convergence and blocking successive recruitment of new cells into these placodes. Further studies revealed genetic interactions between itga5 and Fgf signaling. First, itga5 morphants showed changes in gene expression mimicking modest reduction in Fgf signaling. Second, itga5 morphants showed elevated apoptosis in the otic/epibranchial domain, which was rescued by misexpression of Fgf8. Third, knockdown of the Fgf effector erm had no effect by itself but strongly enhanced defects in itga5 morphants. Finally, proper regulation of itga5 requires dlx3b/4b and pax8, which are themselves regulated by Fgf. These findings support a model in which itga5 coordinates cell migration into posterior placodes and augments Fgf signaling required for patterning of these tissues and cell survival in otic/epibranchial placodes.
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29
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Guillemot F, Zimmer C. From cradle to grave: the multiple roles of fibroblast growth factors in neural development. Neuron 2011; 71:574-88. [PMID: 21867876 DOI: 10.1016/j.neuron.2011.08.002] [Citation(s) in RCA: 150] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/04/2011] [Indexed: 01/08/2023]
Abstract
The generation of a functional nervous system involves a multitude of steps that are controlled by just a few families of extracellular signaling molecules. Among these, the fibroblast growth factor (FGF) family is particularly prominent for the remarkable diversity of its functions. FGFs are best known for their roles in the early steps of patterning of the neural primordium and proliferation of neural progenitors. However, other equally important functions have emerged more recently, including in the later steps of neuronal migration, axon navigation, and synaptogenesis. We review here these diverse functions and discuss the mechanisms that account for this unusual range of activities. FGFs are essential components of most protocols devised to generate therapeutically important neuronal populations in vitro or to stimulate neuronal repair in vivo. How FGFs promote the development of the nervous system and maintain its integrity will thus remain an important focus of research in the future.
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Affiliation(s)
- François Guillemot
- Division of Molecular Neurobiology, Medical Research Council, National Institute for Medical Research, The Ridgeway, Mill Hill, London NW71AA, UK.
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30
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Origin and segregation of cranial placodes in Xenopus laevis. Dev Biol 2011; 360:257-75. [PMID: 21989028 DOI: 10.1016/j.ydbio.2011.09.024] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2011] [Revised: 08/31/2011] [Accepted: 09/01/2011] [Indexed: 11/23/2022]
Abstract
Cranial placodes are local thickenings of the vertebrate head ectoderm that contribute to the paired sense organs (olfactory epithelium, lens, inner ear, lateral line), cranial ganglia and the adenohypophysis. Here we use tissue grafting and dye injections to generated fate maps of the dorsal cranial part of the non-neural ectoderm for Xenopus embryos between neural plate and early tailbud stages. We show that all placodes arise from a crescent-shaped area located around the anterior neural plate, the pre-placodal ectoderm. In agreement with proposed roles of Six1 and Pax genes in the specification of a panplacodal primordium and different placodal areas, respectively, we show that Six1 is expressed uniformly throughout most of the pre-placodal ectoderm, while Pax6, Pax3, Pax8 and Pax2 each are confined to specific subregions encompassing the precursors of different subsets of placodes. However, the precursors of the vagal epibranchial and posterior lateral line placodes, which arise from the posteriormost pre-placodal ectoderm, upregulate Six1 and Pax8/Pax2 only at tailbud stages. Whereas our fate map suggests that regions of origin for different placodes overlap extensively with each other and with other ectodermal fates at neural plate stages, analysis of co-labeled placodes reveals that the actual degree of overlap is much smaller. Time lapse imaging of the pre-placodal ectoderm at single cell resolution demonstrates that no directed, large-scale cell rearrangements occur, when the pre-placodal region segregates into distinct placodes at subsequent stages. Our results indicate that individuation of placodes from the pre-placodal ectoderm does not involve large-scale cell sorting in Xenopus.
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31
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Gunhaga L. The lens: a classical model of embryonic induction providing new insights into cell determination in early development. Philos Trans R Soc Lond B Biol Sci 2011; 366:1193-203. [PMID: 21402580 DOI: 10.1098/rstb.2010.0175] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The lens was the first tissue in which the concept of embryonic induction was demonstrated. For many years lens induction was thought to occur at the time the optic vesicle and lens placode came in contact. Since then, studies have revealed that lens placodal progenitor cells are specified already at gastrula stages, much earlier than previously believed, and independent of optic vesicle interactions. In this review, I will focus on how individual signalling molecules, in particular BMP, FGF, Wnt and Shh, regulate the initial specification of lens placodal cells and the progressive development of lens cells. I will discuss recent work that has shed light on the combination of signalling molecules and the molecular interactions that affect lens specification and proper lens formation. I will also discuss proposed tissue interactions important for lens development. A greater knowledge of the molecular interactions during lens induction is likely to have practical benefits in understanding the causes and consequences of lens diseases. Moreover, knowledge regarding lens induction is providing fundamental important insights into inductive processes in development in general.
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Affiliation(s)
- Lena Gunhaga
- Umeå Center for Molecular Medicine, Umeå University, Building 6M, 4th floor, 901 87 Umeå, Sweden.
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32
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Affiliation(s)
- Thimios A Mitsiadis
- Institute of Oral Biology, Faculty of Medicine, University of Zurich Zurich, Switzerland
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33
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Müller F, O’Rahilly R. The Initial Appearance of the Cranial Nerves and Related Neuronal Migration in Staged Human Embryos. Cells Tissues Organs 2011; 193:215-38. [DOI: 10.1159/000320026] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/02/2010] [Indexed: 11/19/2022] Open
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34
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McLennan R, Kulesa PM. Neuropilin-1 interacts with the second branchial arch microenvironment to mediate chick neural crest cell dynamics. Dev Dyn 2010; 239:1664-73. [PMID: 20503363 DOI: 10.1002/dvdy.22303] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Cranial neural crest cells (NCCs) require neuropilin signaling to reach and invade the branchial arches. Here, we use an in vivo chick model to investigate whether the neuropilin-1 knockdown phenotype is specific to the second branchial arch (ba2), changes in NCC behaviors and phenotypic consequences, and whether neuropilins work together to facilitate entry into and invasion of ba2. We find that cranial NCCs with reduced neuropilin-1 expression displayed shorter protrusions and decreased cell body and nuclear length-to-width ratios characteristic of a loss in polarity and motility, after specific interaction with ba2. Directed NCC migration was rescued by transplantation of transfected NCCs into rhombomere 4 of younger hosts. Lastly, reduction of neuropilin-2 expression by shRNA either solely or with reduction of neuropilin-1 expression did not lead to a stronger head phenotype. Thus, NCCs, independent of rhombomere origin, require neuropilin-1, but not neuropilin-2 to maintain polarity and directed migration into ba2.
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Affiliation(s)
- Rebecca McLennan
- Stowers Institute for Medical Research, Kansas City, Missouri 64110, USA
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35
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Sato S, Ikeda K, Shioi G, Ochi H, Ogino H, Yajima H, Kawakami K. Conserved expression of mouse Six1 in the pre-placodal region (PPR) and identification of an enhancer for the rostral PPR. Dev Biol 2010; 344:158-71. [PMID: 20471971 DOI: 10.1016/j.ydbio.2010.04.029] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2010] [Revised: 04/24/2010] [Accepted: 04/26/2010] [Indexed: 10/19/2022]
Abstract
All cranial sensory organs and sensory neurons of vertebrates develop from cranial placodes. In chick, amphibians and zebrafish, all placodes originate from a common precursor domain, the pre-placodal region (PPR), marked by the expression of Six1/4 and Eya1/2. However, the PPR has never been described in mammals and the mechanism involved in the formation of PPR is poorly defined. Here, we report the expression of Six1 in the horseshoe-shaped mouse ectoderm surrounding the anterior neural plate in a pattern broadly similar to that of non-mammalian vertebrates. To elucidate the identity of Six1-positive mouse ectoderm, we searched for enhancers responsible for Six1 expression by in vivo enhancer assays. One conserved non-coding sequence, Six1-14, showed specific enhancer activity in the rostral PPR of chick and Xenopus and in the mouse ectoderm. These results strongly suggest the presence of PPR in mouse and that it is conserved in vertebrates. Moreover, we show the importance of the homeodomain protein-binding sites of Six1-14, the Six1 rostral PPR enhancer, for enhancer activity, and that Dlx5, Msx1 and Pax7 are candidate binding factors that regulate the level and area of Six1 expression, and thereby the location of the PPR. Our findings provide critical information and tools to elucidate the molecular mechanism of early sensory development and have implications for the development of sensory precursor/stem cells.
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Affiliation(s)
- Shigeru Sato
- Division of Biology, Center for Molecular Medicine, Jichi Medical University, 3311-1 Yakushiji, Shimotsuke, Tochigi 329-0498, Japan.
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Yusvana R, Headon DJ, Markx GH. Creation of arrays of cell aggregates in defined patterns for developmental biology studies using dielectrophoresis. Biotechnol Bioeng 2010; 105:945-54. [PMID: 19953679 DOI: 10.1002/bit.22615] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
It is shown that dielectrophoresis--the movement of particles in non-uniform electric fields--can be used to create engineered skin with artificial placodes of different sizes and shapes, in different spatial patterns. Modeling of the electric field distribution and image analysis of the cell aggregates produced showed that the aggregation is highly predictable. The cells in the aggregates remain viable, and reorganization and compaction of the cells in the aggregates occurs when the artificial skin is subsequently cultured. The system developed could be of considerable use for the in vitro study of developmental processes where local variations in cell density and direct cell-cell contacts are important.
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Affiliation(s)
- Rama Yusvana
- Microstructures and Microenvironments Research Group, Department of Chemical Engineering, School of Engineering and Physical Sciences, Heriot-Watt University, Riccarton, Edinburgh EH14 4AS, Scotland, UK
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Urness LD, Paxton CN, Wang X, Schoenwolf GC, Mansour SL. FGF signaling regulates otic placode induction and refinement by controlling both ectodermal target genes and hindbrain Wnt8a. Dev Biol 2010; 340:595-604. [PMID: 20171206 PMCID: PMC2854211 DOI: 10.1016/j.ydbio.2010.02.016] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2010] [Revised: 02/10/2010] [Accepted: 02/10/2010] [Indexed: 12/25/2022]
Abstract
The inner ear epithelium, with its complex array of sensory, non-sensory, and neuronal cell types necessary for hearing and balance, is derived from a thickened patch of head ectoderm called the otic placode. Mouse embryos lacking both Fgf3 and Fgf10 fail to initiate inner ear development because appropriate patterns of gene expression fail to be specified within the pre-otic field. To understand the transcriptional "blueprint" initiating inner ear development, we used microarray analysis to identify prospective placode genes that were differentially expressed in control and Fgf3(-)(/)(-);Fgf10(-)(/)(-) embryos. Several genes in the down-regulated class, including Hmx3, Hmx2, Foxg1, Sox9, Has2, and Slc26a9 were validated by in situ hybridization. We also assayed candidate target genes suggested by other studies of otic induction. Two placode markers, Fgf4 and Foxi3, were down-regulated in Fgf3(-)(/)(-);Fgf10(-)(/)(-) embryos, whereas Foxi2, a cranial epidermis marker, was expanded in double mutants, similar to its behavior when WNT responses are blocked in the otic placode. Assays of hindbrain Wnt genes revealed that only Wnt8a was reduced or absent in FGF-deficient embryos, and that even some Fgf3(-)(/)(-);Fgf10(-)(/+) and Fgf3(-)(/)(-) embryos failed to express Wnt8a, suggesting a key role for Fgf3, and a secondary role for Fgf10, in Wnt8a expression. Chick explant assays showed that FGF3 or FGF4, but not FGF10, were sufficient to induce Wnt8a. Collectively, our results suggest that Wnt8a provides the link between FGF-induced formation of the pre-otic field and restriction of the otic placode to ectoderm adjacent to the hindbrain.
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Affiliation(s)
- Lisa D. Urness
- Department of Human Genetics, University of Utah, 15 N 2030 E, RM 2100, Salt Lake City, UT 84112-5330, USA
| | - Christian N. Paxton
- Department of Neurobiology and Anatomy, University of Utah, 30 N 1900 E, RM 2R066 SOM, Salt Lake City, UT 84132-3401, USA
| | - Xiaofen Wang
- Department of Human Genetics, University of Utah, 15 N 2030 E, RM 2100, Salt Lake City, UT 84112-5330, USA
| | - Gary C. Schoenwolf
- Department of Neurobiology and Anatomy, University of Utah, 30 N 1900 E, RM 2R066 SOM, Salt Lake City, UT 84132-3401, USA
| | - Suzanne L. Mansour
- Department of Human Genetics, University of Utah, 15 N 2030 E, RM 2100, Salt Lake City, UT 84112-5330, USA
- Department of Neurobiology and Anatomy, University of Utah, 30 N 1900 E, RM 2R066 SOM, Salt Lake City, UT 84132-3401, USA
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Schlosser G. Making senses development of vertebrate cranial placodes. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2010; 283:129-234. [PMID: 20801420 DOI: 10.1016/s1937-6448(10)83004-7] [Citation(s) in RCA: 142] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Cranial placodes (which include the adenohypophyseal, olfactory, lens, otic, lateral line, profundal/trigeminal, and epibranchial placodes) give rise to many sense organs and ganglia of the vertebrate head. Recent evidence suggests that all cranial placodes may be developmentally related structures, which originate from a common panplacodal primordium at neural plate stages and use similar regulatory mechanisms to control developmental processes shared between different placodes such as neurogenesis and morphogenetic movements. After providing a brief overview of placodal diversity, the present review summarizes current evidence for the existence of a panplacodal primordium and discusses the central role of transcription factors Six1 and Eya1 in the regulation of processes shared between different placodes. Upstream signaling events and transcription factors involved in early embryonic induction and specification of the panplacodal primordium are discussed next. I then review how individual placodes arise from the panplacodal primordium and present a model of multistep placode induction. Finally, I briefly summarize recent advances concerning how placodal neurons and sensory cells are specified, and how morphogenesis of placodes (including delamination and migration of placode-derived cells and invagination) is controlled.
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Affiliation(s)
- Gerhard Schlosser
- Zoology, School of Natural Sciences & Martin Ryan Institute, National University of Ireland, Galway, Ireland
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Kriebitz NN, Kiecker C, McCormick L, Lumsden A, Graham A, Bell E. PRDC regulates placode neurogenesis in chick by modulating BMP signalling. Dev Biol 2009; 336:280-92. [PMID: 19836367 DOI: 10.1016/j.ydbio.2009.10.013] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2009] [Revised: 10/08/2009] [Accepted: 10/08/2009] [Indexed: 01/09/2023]
Abstract
The epibranchial placodes generate the neurons of the geniculate, petrosal, and nodose cranial sensory ganglia. Previously, it has been shown that bone morphogenetic proteins (BMPs) are involved in the formation of these structures. However, it has been unclear as to whether BMP signalling has an ongoing function in directing the later development of the epibranchial placodes, and how this signalling is regulated. Here, we demonstrate that BMPs maintain placodal neurogenesis and that their activity is modulated by a member of the Cerberus/Dan family of BMP antagonists, Protein Related to Dan and Cerberus (PRDC). We find that Bmp4 is expressed in the epibranchial placodes while Bmp7 and PRDC are expressed in the pharyngeal pouches. The timing and regional expression of these three genes suggest that BMP7 is involved in inducing placode neurogenesis and BMP4 in maintaining it and that BMP activity is modulated by PRDC. To investigate this hypothesis, we have performed both gain- and loss- of-function experiments with PRDC and find that it can modulate the BMP signals that induce epibranchial neurogenesis: a gain of PRDC function results in a loss of Bmp4 and hence placode neurogenesis is inhibited; conversely, a loss of PRDC function induces ectopic Bmp4 and an expansion of placode neurogenesis. This modulation is therefore necessary for the number and positioning of the epibranchial neurons.
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Affiliation(s)
- Nadja N Kriebitz
- MRC Centre for Developmental Neurobiology, 4th Floor New Hunts House, Kings College London, Guy's Campus, London SE1 1UL, UK
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