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Chrysostomou E, Mourikis P. The extracellular matrix niche of muscle stem cells. Curr Top Dev Biol 2024; 158:123-150. [PMID: 38670702 DOI: 10.1016/bs.ctdb.2024.01.021] [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: 04/28/2024]
Abstract
Preserving the potency of stem cells in adult tissues is very demanding and relies on the concerted action of various cellular and non-cellular elements in a precise stoichiometry. This balanced microenvironment is found in specific anatomical "pockets" within the tissue, known as the stem cell niche. In this review, we explore the interplay between stem cells and their niches, with a primary focus on skeletal muscle stem cells and the extracellular matrix (ECM). Quiescent muscle stem cells, known as satellite cells are active producers of a diverse array of ECM molecules, encompassing major constituents like collagens, laminins, and integrins, some of which are explored in this review. The conventional perception of ECM as merely a structural scaffold is evolving. Collagens can directly interact as ligands with receptors on satellite cells, while other ECM proteins have the capacity to sequester growth factors and regulate their release, especially relevant during satellite cell turnover in homeostasis or activation upon injury. Additionally, we explore an evolutionary perspective on the ECM across a range of multicellular organisms and discuss a model wherein satellite cells are self-sustained by generating their own niche. Considering the prevalence of ECM proteins in the connective tissue of various organs it is not surprising that mutations in ECM genes have pathological implications, including in muscle, where they can lead to myopathies. However, the particular role of certain disease-related ECM proteins in stem cell maintenance highlights the potential contribution of stem cell deregulation to the progression of these disorders.
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Affiliation(s)
- Eleni Chrysostomou
- Université Paris Est Créteil, Institut National de la Santé et de la Recherche Médicale (INSERM), Mondor Institute for Biomedical Research (IMRB), Créteil, France
| | - Philippos Mourikis
- Université Paris Est Créteil, Institut National de la Santé et de la Recherche Médicale (INSERM), Mondor Institute for Biomedical Research (IMRB), Créteil, France.
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2
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Avalos PN, Forsthoefel DJ. An Emerging Frontier in Intercellular Communication: Extracellular Vesicles in Regeneration. Front Cell Dev Biol 2022; 10:849905. [PMID: 35646926 PMCID: PMC9130466 DOI: 10.3389/fcell.2022.849905] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Accepted: 03/28/2022] [Indexed: 12/12/2022] Open
Abstract
Regeneration requires cellular proliferation, differentiation, and other processes that are regulated by secreted cues originating from cells in the local environment. Recent studies suggest that signaling by extracellular vesicles (EVs), another mode of paracrine communication, may also play a significant role in coordinating cellular behaviors during regeneration. EVs are nanoparticles composed of a lipid bilayer enclosing proteins, nucleic acids, lipids, and other metabolites, and are secreted by most cell types. Upon EV uptake by target cells, EV cargo can influence diverse cellular behaviors during regeneration, including cell survival, immune responses, extracellular matrix remodeling, proliferation, migration, and differentiation. In this review, we briefly introduce the history of EV research and EV biogenesis. Then, we review current understanding of how EVs regulate cellular behaviors during regeneration derived from numerous studies of stem cell-derived EVs in mammalian injury models. Finally, we discuss the potential of other established and emerging research organisms to expand our mechanistic knowledge of basic EV biology, how injury modulates EV biogenesis, cellular sources of EVs in vivo, and the roles of EVs in organisms with greater regenerative capacity.
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Affiliation(s)
- Priscilla N. Avalos
- Department of Cell Biology, College of Medicine, The University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
- Genes and Human Disease Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, United States
| | - David J. Forsthoefel
- Department of Cell Biology, College of Medicine, The University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
- Genes and Human Disease Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, United States
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3
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Traffic light Hydra allows for simultaneous in vivo imaging of all three cell lineages. Dev Biol 2022; 488:74-80. [DOI: 10.1016/j.ydbio.2022.05.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Revised: 05/06/2022] [Accepted: 05/10/2022] [Indexed: 11/19/2022]
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4
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Martinez P, Ballarin L, Ereskovsky AV, Gazave E, Hobmayer B, Manni L, Rottinger E, Sprecher SG, Tiozzo S, Varela-Coelho A, Rinkevich B. Articulating the "stem cell niche" paradigm through the lens of non-model aquatic invertebrates. BMC Biol 2022; 20:23. [PMID: 35057814 PMCID: PMC8781081 DOI: 10.1186/s12915-022-01230-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Accepted: 01/12/2022] [Indexed: 12/13/2022] Open
Abstract
Stem cells (SCs) in vertebrates typically reside in "stem cell niches" (SCNs), morphologically restricted tissue microenvironments that are important for SC survival and proliferation. SCNs are broadly defined by properties including physical location, but in contrast to vertebrates and other "model" organisms, aquatic invertebrate SCs do not have clearly documented niche outlines or properties. Life strategies such as regeneration or asexual reproduction may have conditioned the niche architectural variability in aquatic or marine animal groups. By both establishing the invertebrates SCNs as independent types, yet allowing inclusiveness among them, the comparative analysis will allow the future functional characterization of SCNs.
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Affiliation(s)
- P Martinez
- Departament de Genètica, Microbiologia i Estadística, Universitat de Barcelona, Av. Diagonal 643, 08028, Barcelona, Spain.
- Institut Català de Recerca i Estudis Avançats (ICREA), Barcelona, Spain.
| | - L Ballarin
- Department of Biology, University of Padova, Via U. Bassi 58/B, 35100, Padova, Italy
| | - A V Ereskovsky
- Aix Marseille University, Avignon Université, CNRS, IRD, IMBE, Marseille, France
- St. Petersburg State University, Biological Faculty, Universitetskaya emb. 7/9, St. Petersburg, 199034, Russia
- N. K. Koltzov Institute of Developmental Biology, Russian Academy of Sciences, Vavilova Street 26, Moscow, 119334, Russia
| | - E Gazave
- Université de Paris, CNRS, Institut Jacques Monod, F-75006, Paris, France
| | - B Hobmayer
- Department of Zoology and Center of Molecular Biosciences, University of Innsbruck, Technikerstr. 25, 6020, Innsbruck, Austria
| | - L Manni
- Department of Biology, University of Padova, Via U. Bassi 58/B, 35100, Padova, Italy
| | - E Rottinger
- Université Côte d'Azur, CNRS, INSERM, Institute for Research on Cancer and Aging, Nice (IRCAN), Nice, France
- Université Côte d'Azur, Federative Research Institute - Marine Resources (IFR MARRES), Nice, France
| | - S G Sprecher
- Department of Biology, University of Fribourg, Chemin du Musee 10, 1700, Fribourg, Switzerland
| | - S Tiozzo
- Sorbonne Université, CNRS, Laboratoire de Biologie du Développement de Villefranche-sur-mer (LBDV), Paris, France
| | - A Varela-Coelho
- ITQB NOVA, Instituto de Tecnologia Química e Biológica António Xavier, Av. da República, 2780-157, Oeiras, Portugal
| | - B Rinkevich
- Israel Oceanography and Limnological Research, National Institute of Oceanography, Tel Shikmona, P.O. Box 8030, 31080, Haifa, Israel.
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5
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Bideau L, Kerner P, Hui J, Vervoort M, Gazave E. Animal regeneration in the era of transcriptomics. Cell Mol Life Sci 2021; 78:3941-3956. [PMID: 33515282 PMCID: PMC11072743 DOI: 10.1007/s00018-021-03760-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 01/04/2021] [Accepted: 01/09/2021] [Indexed: 12/27/2022]
Abstract
Animal regeneration, the ability to restore a lost body part, is a process that has fascinated scientists for centuries. In this review, we first present what regeneration is and how it relates to development, as well as the widespread and diverse nature of regeneration in animals. Despite this diversity, animal regeneration includes three common mechanistic steps: initiation, induction and activation of progenitors, and morphogenesis. In this review article, we summarize and discuss, from an evolutionary perspective, the recent data obtained for a variety of regeneration models which have allowed to identify key shared mechanisms that control these main steps of animal regeneration. This review also synthesizes the wealth of high-throughput mRNA sequencing data (bulk mRNA-seq) concerning regeneration which have been obtained in recent years, highlighting the major advances in the regeneration field that these studies have revealed. We stress out that, through a comparative approach, these data provide opportunities to further shed light on the evolution of regeneration in animals. Finally, we point out how the use of single-cell mRNA-seq technology and integration with epigenomic approaches may further help researchers to decipher mechanisms controlling regeneration and their evolution in animals.
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Affiliation(s)
- Loïc Bideau
- Université de Paris, CNRS, Institut Jacques Monod, 75006, Paris, France
| | - Pierre Kerner
- Université de Paris, CNRS, Institut Jacques Monod, 75006, Paris, France
| | - Jerome Hui
- School of Life Sciences, Simon F.S. Li Marine Science Laboratory, State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Hong Kong, China
| | - Michel Vervoort
- Université de Paris, CNRS, Institut Jacques Monod, 75006, Paris, France.
| | - Eve Gazave
- Université de Paris, CNRS, Institut Jacques Monod, 75006, Paris, France.
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6
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A novel bilateral grafting technique for studying patterning in Hydra. Dev Biol 2020; 462:60-65. [PMID: 32165148 DOI: 10.1016/j.ydbio.2020.03.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Accepted: 03/06/2020] [Indexed: 11/21/2022]
Abstract
Control of patterning and the specification of body axes are fundamental aspects of animal development involving complex interactions between chemical, physical, and genetic signals. The freshwater polyp Hydra has long been recognized as a useful model system to address these questions due to its simple anatomy, optical transparency, and strong regenerative abilities, which enabled clever grafting experiments to alter and probe patterning. Reliable methods exist for the transplantation of small tissue pieces into the body column or the combination of sections cut perpendicular to the body axis, which can be used to examine oral-aboral gradients and axis induction potential of tissue fragments. However, existing methods do not allow researchers to probe questions of axis alignment and lateral information exchange. We therefore developed a technique to produce chimeric animals split longitudinally along the body axis of the animal by anesthetizing the animals with the terpene linalool and threading the donor pieces onto pairs of fine glass needles. Our novel approach can be applied to study questions in Hydra research that have thus far been inaccessible, including patterning processes acting perpendicular to the oral-aboral axis and the extent of lateral cell migration.
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7
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Frank U, Nicotra ML, Schnitzler CE. The colonial cnidarian Hydractinia. EvoDevo 2020; 11:7. [PMID: 32226598 PMCID: PMC7098123 DOI: 10.1186/s13227-020-00151-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Accepted: 03/12/2020] [Indexed: 11/27/2022] Open
Abstract
Hydractinia, a genus of colonial marine cnidarians, has been used as a model organism for developmental biology and comparative immunology for over a century. It was this animal where stem cells and germ cells were first studied. However, protocols for efficient genetic engineering have only recently been established by a small but interactive community of researchers. The animal grows well in the lab, spawns daily, and its relatively short life cycle allows genetic studies. The availability of genomic tools and resources opens further opportunities for research using this animal. Its accessibility to experimental manipulation, growth- and cellular-plasticity, regenerative ability, and resistance to aging and cancer place Hydractinia as an emerging model for research in many biological and environmental disciplines.
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Affiliation(s)
- Uri Frank
- 1Centre for Chromosome Biology, School of Natural Sciences, National University of Ireland Galway, Galway, Ireland
| | - Matthew L Nicotra
- 2Departments of Surgery and Immunology, Center for Evolutionary Biology and Medicine, Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA 15261 USA
| | - Christine E Schnitzler
- 3Whitney Laboratory for Marine Bioscience, University of Florida, St. Augustine, FL 320803 USA.,4Department of Biology, University of Florida, Gainesville, FL 32611 USA
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8
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Abstract
The freshwater polyp Hydra provides a potent model system for investigating the conditions that promote wound healing, reactivation of a developmental process and, ultimately, regeneration of an amputated body part. Hydra polyps can also be dissociated to the single cell level and can regenerate a complete body axis from aggregates, behaving as natural organoids. In recent years, the ability to exploit Hydra has been expanded with the advent of new live-imaging approaches, genetic manipulations that include stable transgenesis, gene silencing and genome editing, and the accumulation of high-throughput omics data. In this Primer, we provide an overview of Hydra as a model system for studying regeneration, highlighting recent results that question the classical self-enhancement and long-range inhibition model supposed to drive Hydra regeneration. We underscore the need for integrative explanations incorporating biochemical as well as mechanical signalling.
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Affiliation(s)
- Matthias C Vogg
- Department of Genetics and Evolution, Institute of Genetics and Genomics in Geneva (iGE3), Faculty of Sciences, University of Geneva, 30 Quai Ernest Ansermet, CH-1211 Geneva 4, Switzerland
| | - Brigitte Galliot
- Department of Genetics and Evolution, Institute of Genetics and Genomics in Geneva (iGE3), Faculty of Sciences, University of Geneva, 30 Quai Ernest Ansermet, CH-1211 Geneva 4, Switzerland
| | - Charisios D Tsiairis
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, CH-4058 Basel, Switzerland
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9
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Condamine T, Jager M, Leclère L, Blugeon C, Lemoine S, Copley RR, Manuel M. Molecular characterisation of a cellular conveyor belt in Clytia medusae. Dev Biol 2019; 456:212-225. [PMID: 31509769 DOI: 10.1016/j.ydbio.2019.09.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Revised: 07/29/2019] [Accepted: 09/07/2019] [Indexed: 11/25/2022]
Abstract
The tentacular system of Clytia hemisphaerica medusa (Cnidaria, Hydrozoa) has recently emerged as a promising experimental model to tackle the developmental mechanisms that regulate cell lineage progression in an early-diverging animal phylum. From a population of proximal stem cells, the successive steps of tentacle stinging cell (nematocyte) elaboration, are spatially ordered along a "cellular conveyor belt". Furthermore, the C. hemisphaerica tentacular system exhibits bilateral organisation, with two perpendicular polarity axes (proximo-distal and oral-aboral). We aimed to improve our knowledge of this cellular system by combining RNAseq-based differential gene expression analyses and expression studies of Wnt signalling genes. RNAseq comparisons of gene expression levels were performed (i) between the tentacular system and a control medusa deprived of all tentacles, nematogenic sites and gonads, and (ii) between three samples staggered along the cellular conveyor belt. The behaviour in these differential expression analyses of two reference gene sets (stem cell genes; nematocyte genes), as well as the relative representations of selected gene ontology categories, support the validity of the cellular conveyor belt model. Expression patterns obtained by in situ hybridisation for selected highly differentially expressed genes and for Wnt signalling genes are largely consistent with the results from RNAseq. Wnt signalling genes exhibit complex spatial deployment along both polarity axes of the tentacular system, with the Wnt/β-catenin pathway probably acting along the oral-aboral axis rather than the proximo-distal axis. These findings reinforce the idea that, despite overall radial symmetry, cnidarians have a full potential for elaboration of bilateral structures based on finely orchestrated deployment of an ancient developmental gene toolkit.
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Affiliation(s)
- Thomas Condamine
- Sorbonne Université, MNHN, CNRS, EPHE, Institut de Systématique, Evolution, Biodiversité (ISYEB UMR 7205), Paris, France
| | - Muriel Jager
- Sorbonne Université, MNHN, CNRS, EPHE, Institut de Systématique, Evolution, Biodiversité (ISYEB UMR 7205), Paris, France
| | - Lucas Leclère
- Sorbonne Université, CNRS, Laboratoire de Biologie du Développement de Villefranche-sur-mer (LBDV) UMR7009, 181 chemin du Lazaret, 06230, Villefranche-sur-mer, France
| | - Corinne Blugeon
- Genomic Paris Centre, Institut de Biologie de l'Ecole Normale Supérieure (IBENS), Ecole Normale Supérieure, CNRS, INSERM, PSL Université Paris, 75005, Paris, France
| | - Sophie Lemoine
- Genomic Paris Centre, Institut de Biologie de l'Ecole Normale Supérieure (IBENS), Ecole Normale Supérieure, CNRS, INSERM, PSL Université Paris, 75005, Paris, France
| | - Richard R Copley
- Sorbonne Université, CNRS, Laboratoire de Biologie du Développement de Villefranche-sur-mer (LBDV) UMR7009, 181 chemin du Lazaret, 06230, Villefranche-sur-mer, France
| | - Michaël Manuel
- Sorbonne Université, MNHN, CNRS, EPHE, Institut de Systématique, Evolution, Biodiversité (ISYEB UMR 7205), Paris, France.
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10
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Transgenesis in Hydra to characterize gene function and visualize cell behavior. Nat Protoc 2019; 14:2069-2090. [DOI: 10.1038/s41596-019-0173-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Accepted: 04/04/2019] [Indexed: 12/13/2022]
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11
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Impact of cycling cells and cell cycle regulation on Hydra regeneration. Dev Biol 2018; 433:240-253. [DOI: 10.1016/j.ydbio.2017.11.003] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Revised: 10/31/2017] [Accepted: 11/08/2017] [Indexed: 01/12/2023]
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12
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Rentzsch F, Layden M, Manuel M. The cellular and molecular basis of cnidarian neurogenesis. WILEY INTERDISCIPLINARY REVIEWS-DEVELOPMENTAL BIOLOGY 2016; 6. [PMID: 27882698 PMCID: PMC6680159 DOI: 10.1002/wdev.257] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Revised: 08/30/2016] [Accepted: 09/21/2016] [Indexed: 12/22/2022]
Abstract
Neurogenesis initiates during early development and it continues through later developmental stages and in adult animals to enable expansion, remodeling, and homeostasis of the nervous system. The generation of nerve cells has been analyzed in detail in few bilaterian model organisms, leaving open many questions about the evolution of this process. As the sister group to bilaterians, cnidarians occupy an informative phylogenetic position to address the early evolution of cellular and molecular aspects of neurogenesis and to understand common principles of neural development. Here we review studies in several cnidarian model systems that have revealed significant similarities and interesting differences compared to neurogenesis in bilaterian species, and between different cnidarian taxa. Cnidarian neurogenesis is currently best understood in the sea anemone Nematostella vectensis, where it includes epithelial neural progenitor cells that express transcription factors of the soxB and atonal families. Notch signaling regulates the number of these neural progenitor cells, achaete‐scute and dmrt genes are required for their further development and Wnt and BMP signaling appear to be involved in the patterning of the nervous system. In contrast to many vertebrates and Drosophila, cnidarians have a high capacity to generate neurons throughout their lifetime and during regeneration. Utilizing this feature of cnidarian biology will likely allow gaining new insights into the similarities and differences of embryonic and regenerative neurogenesis. The use of different cnidarian model systems and their expanding experimental toolkits will thus continue to provide a better understanding of evolutionary and developmental aspects of nervous system formation. WIREs Dev Biol 2017, 6:e257. doi: 10.1002/wdev.257 This article is categorized under:
Gene Expression and Transcriptional Hierarchies > Cellular Differentiation Signaling Pathways > Cell Fate Signaling Comparative Development and Evolution > Organ System Comparisons Between Species
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Affiliation(s)
- Fabian Rentzsch
- Sars Centre for Marine Molecular Biology, University of Bergen, Bergen, Norway
| | | | - Michaël Manuel
- Sorbonne Universités, UMPC Univ Paris 06, CNRS, Evolution Paris-Seine, Institut de Biologie Paris-Seine (IBPS), Paris, France
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Siebert S, Goetz FE, Church SH, Bhattacharyya P, Zapata F, Haddock SHD, Dunn CW. Stem cells in Nanomia bijuga (Siphonophora), a colonial animal with localized growth zones. EvoDevo 2015; 6:22. [PMID: 26090088 PMCID: PMC4471933 DOI: 10.1186/s13227-015-0018-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Accepted: 05/11/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Siphonophores (Hydrozoa) have unparalleled colony-level complexity, precision of colony organization, and functional specialization between zooids (i.e., the units that make up colonies). Previous work has shown that, unlike other colonial animals, most growth in siphonophores is restricted to one or two well-defined growth zones that are the sites of both elongation and zooid budding. It remained unknown, however, how this unique colony growth and development is realized at the cellular level. RESULTS To understand the colony-level growth and development of siphonophores at the cellular level, we characterize the distribution of proliferating cells and interstitial stem cells (i-cells) in the siphonophore Nanomia bijuga. Within the colony, we find evidence that i-cells are present at the tip of the horn, the structure within the growth zone that gives rise to new zooids. Co-localized gene expression of vasa-1, pl10, piwi, nanos-1, and nanos-2 suggests that i-cells persist in the youngest zooid buds and that i-cells become progressively restricted to specific regions within the zooids until they are mostly absent from the oldest zooids. The examined genes remain expressed in gametogenic regions. No evidence for i-cells is found in the stem between maturing zooids. Domains of high cell proliferation include regions where the examined genes are expressed, but also include some areas in which the examined genes were not expressed such as the stem within the growth zones. Cell proliferation in regions devoid of vasa-1, pl10, piwi, nanos-1, and nanos-2 expression indicates the presence of mitotically active epithelial cell lineages and, potentially, progenitor cell populations. CONCLUSIONS We provide the first evidence for i-cells in a siphonophore. Our findings suggest maintenance of i-cell populations at the sites of growth zones and that these sites are the main source of i-cells. This restriction of stem cells to particular regions in the colony, in combination with localized budding and spatial patterning during pro-bud subdivision, may play a major role in facilitating the precision of siphonophore growth. Spatially restricted maintenance of i-cells in mature zooids and absence of i-cells along the stem may explain the reduced developmental plasticity in older parts of the colony.
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Affiliation(s)
- Stefan Siebert
- Department of Ecology and Evolutionary Biology, Brown University, 80 Waterman St. Box GW, Providence, RI 02912 USA
| | - Freya E Goetz
- Department of Invertebrate Zoology, National Museum of Natural History, Smithsonian Institution, Washington, District of Columbia, 20004 Washington USA
| | - Samuel H Church
- Department of Ecology and Evolutionary Biology, Brown University, 80 Waterman St. Box GW, Providence, RI 02912 USA
| | - Pathikrit Bhattacharyya
- Department of Ecology and Evolutionary Biology, Brown University, 80 Waterman St. Box GW, Providence, RI 02912 USA
| | - Felipe Zapata
- Department of Ecology and Evolutionary Biology, Brown University, 80 Waterman St. Box GW, Providence, RI 02912 USA
| | | | - Casey W Dunn
- Department of Ecology and Evolutionary Biology, Brown University, 80 Waterman St. Box GW, Providence, RI 02912 USA
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14
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Dynamic expression of a Hydra FGF at boundaries and termini. Dev Genes Evol 2014; 224:235-44. [PMID: 25311911 DOI: 10.1007/s00427-014-0480-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2014] [Accepted: 09/17/2014] [Indexed: 10/24/2022]
Abstract
Guidance of cells and tissue sheets is an essential function in developing and differentiating animal tissues. In Hydra, where cells and tissue move dynamically due to constant cell proliferation towards the termini or into lateral, vegetative buds, factors essential for guidance are still unknown. Good candidates to take over this function are fibroblast growth factors (FGFs). We present the phylogeny of several Hydra FGFs and analysis of their expression patterns. One of the FGFs is expressed in all terminal regions targeted by tissue movement and at boundaries crossed by moving tissue and cells with an expression pattern slightly differing in two Hydra strains. A model addressing an involvement of this FGF in cell movement and morphogenesis is proposed: Hydra FGFf-expressing cells might serve as sources to attract tissue and cells towards the termini of the body column and across morphological boundaries. Moreover, a function in morphogenesis and/or differentiation of cells and tissue is suggested.
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15
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Juliano CE, Lin H, Steele RE. Generation of transgenic Hydra by embryo microinjection. J Vis Exp 2014:51888. [PMID: 25285460 DOI: 10.3791/51888] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
As a member of the phylum Cnidaria, the sister group to all bilaterians, Hydra can shed light on fundamental biological processes shared among multicellular animals. Hydra is used as a model for the study of regeneration, pattern formation, and stem cells. However, research efforts have been hampered by lack of a reliable method for gene perturbations to study molecular function. The development of transgenic methods has revitalized the study of Hydra biology(1). Transgenic Hydra allow for the tracking of live cells, sorting to yield pure cell populations for biochemical analysis, manipulation of gene function by knockdown and over-expression, and analysis of promoter function. Plasmid DNA injected into early stage embryos randomly integrates into the genome early in development. This results in hatchlings that express transgenes in patches of tissue in one or more of the three lineages (ectodermal epithelial, endodermal epithelial, or interstitial). The success rate of obtaining a hatchling with transgenic tissue is between 10% and 20%. Asexual propagation of the transgenic hatchling is used to establish a uniformly transgenic line in a particular lineage. Generating transgenic Hydra is surprisingly simple and robust, and here we describe a protocol that can be easily implemented at low cost.
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Affiliation(s)
- Celina E Juliano
- Yale Stem Cell Center and Department of Cell Biology, Yale University School of Medicine;
| | - Haifan Lin
- Yale Stem Cell Center and Department of Cell Biology, Yale University School of Medicine
| | - Robert E Steele
- Department of Biological Chemistry and the Developmental Biology Center, University of California, Irvine;
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16
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Abstract
Most epithelia in animals are colonized by microbial communities. These resident microbes influence fitness and thus ecologically important traits of their hosts, ultimately forming a metaorganism consisting of a multicellular host and a community of associated microorganisms. Recent discoveries in the cnidarian Hydra show that components of the innate immune system as well as transcriptional regulators of stem cells are involved in maintaining homeostasis between animals and their resident microbiota. Here I argue that components of the innate immune system with its host-specific antimicrobial peptides and a rich repertoire of pattern recognition receptors evolved in early-branching metazoans because of the need to control the resident beneficial microbes, not because of invasive pathogens. I also propose a mutual intertwinement between the stem cell regulatory machinery of the host and the resident microbiota composition, such that disturbances in one trigger a restructuring and resetting of the other.
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