1
|
Atajanova T, Kang EM, Postnikova A, Price AL, Doerr S, Du M, Ugenti A, Ragkousi K. Lateral cell polarization drives organization of epithelia in sea anemone embryos and embryonic cell aggregates. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.07.588493. [PMID: 38645007 PMCID: PMC11030385 DOI: 10.1101/2024.04.07.588493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/23/2024]
Abstract
One of the first organizing processes during animal development is the assembly of embryonic cells into epithelia. In certain animals, including Hydra and sea anemones, epithelia also emerge when cells from dissociated tissues are aggregated back together. Although cell adhesion is required to keep cells together, it is not clear whether cell polarization plays a role as epithelia emerge from disordered aggregates. Here, we demonstrate that lateral cell polarization is essential for epithelial organization in both embryos and aggregates of the sea anemone Nematostella vectensis. Specifically, knock down of the lateral polarity protein Lgl disrupts epithelia in developing embryos and impairs the capacity of dissociated cells to epithelialize from aggregates. Cells in lgl mutant epithelia lose their columnar shape and have mispositioned mitotic spindles and ciliary basal bodies. Together, our data suggest that in Nematostella, Lgl is required to establish lateral cell polarity and position cytoskeletal organelles in cells of embryos and aggregates during de novo epithelial organization.
Collapse
Affiliation(s)
- Tavus Atajanova
- Department of Biology, Amherst College, Amherst, MA 01002, USA
- Present address: Dana-Farber Cancer Institute, Boston, MA 02215, USA
| | | | - Anna Postnikova
- Department of Biology, Amherst College, Amherst, MA 01002, USA
| | | | - Sophia Doerr
- Department of Biology, Amherst College, Amherst, MA 01002, USA
- Present address: Department of Biology, Institute of Molecular Biology, University of Oregon, Eugene, OR 97403, USA
| | - Michael Du
- Department of Biology, Amherst College, Amherst, MA 01002, USA
| | - Alicia Ugenti
- Department of Biology, Amherst College, Amherst, MA 01002, USA
| | | |
Collapse
|
2
|
Skokan TD, Hobmayer B, McKinley KL, Vale RD. Mechanical stretch regulates macropinocytosis in Hydra vulgaris. Mol Biol Cell 2024; 35:br9. [PMID: 38265917 PMCID: PMC10916863 DOI: 10.1091/mbc.e22-02-0065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Revised: 01/12/2024] [Accepted: 01/19/2024] [Indexed: 01/26/2024] Open
Abstract
Cells rely on a diverse array of engulfment processes to sense, exploit, and adapt to their environments. Among these, macropinocytosis enables indiscriminate and rapid uptake of large volumes of fluid and membrane, rendering it a highly versatile engulfment strategy. Much of the molecular machinery required for macropinocytosis has been well established, yet how this process is regulated in the context of organs and organisms remains poorly understood. Here, we report the discovery of extensive macropinocytosis in the outer epithelium of the cnidarian Hydra vulgaris. Exploiting Hydra's relatively simple body plan, we developed approaches to visualize macropinocytosis over extended periods of time, revealing constitutive engulfment across the entire body axis. We show that the direct application of planar stretch leads to calcium influx and the inhibition of macropinocytosis. Finally, we establish a role for stretch-activated channels in inhibiting this process. Together, our approaches provide a platform for the mechanistic dissection of constitutive macropinocytosis in physiological contexts and highlight a potential role for macropinocytosis in responding to cell surface tension.
Collapse
Affiliation(s)
- Taylor D. Skokan
- Howard Hughes Medical Institute and Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA 94158
| | - Bert Hobmayer
- Department of Zoology and Centre for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Technikerstr. 25, A-6020 Innsbruck, Austria
| | - Kara L. McKinley
- Howard Hughes Medical Institute and Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA 02138
| | - Ronald D. Vale
- Howard Hughes Medical Institute and Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA 94158
- Howard Hughes Medical Institute Janelia Research Campus, Ashburn, VA, 20147
| |
Collapse
|
3
|
Wang R, Bialas AL, Goel T, Collins EMS. Mechano-Chemical Coupling in Hydra Regeneration and Patterning. Integr Comp Biol 2023; 63:1422-1441. [PMID: 37339912 DOI: 10.1093/icb/icad070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 06/07/2023] [Accepted: 06/12/2023] [Indexed: 06/22/2023] Open
Abstract
The freshwater cnidarian Hydra can regenerate from wounds, small tissue fragments and even from aggregated cells. This process requires the de novo development of a body axis and oral-aboral polarity, a fundamental developmental process that involves chemical patterning and mechanical shape changes. Gierer and Meinhardt recognized that Hydra's simple body plan and amenability to in vivo experiments make it an experimentally and mathematically tractable model to study developmental patterning and symmetry breaking. They developed a reaction-diffusion model, involving a short-range activator and a long-range inhibitor, which successfully explained patterning in the adult animal. In 2011, HyWnt3 was identified as a candidate for the activator. However, despite the continued efforts of both physicists and biologists, the predicted inhibitor remains elusive. Furthermore, the Gierer-Meinhardt model cannot explain de novo axis formation in cellular aggregates that lack inherited tissue polarity. The aim of this review is to synthesize the current knowledge on Hydra symmetry breaking and patterning. We summarize the history of patterning studies and insights from recent biomechanical and molecular studies, and highlight the need for continued validation of theoretical assumptions and collaboration across disciplinary boundaries. We conclude by proposing new experiments to test current mechano-chemical coupling models and suggest ideas for expanding the Gierer-Meinhardt model to explain de novo patterning, as observed in Hydra aggregates. The availability of a fully sequenced genome, transgenic fluorescent reporter strains, and modern imaging techniques, that enable unprecedented observation of cellular events in vivo, promise to allow the community to crack Hydra's secret to patterning.
Collapse
Affiliation(s)
- Rui Wang
- Department of Bioengineering, University of California San Diego, 9500 Gilman Drive, La Jolla, 92093 CA, USA
| | - April L Bialas
- Department of Biology, Swarthmore College, 500 College Ave, Swarthmore, 19081 PA, USA
| | - Tapan Goel
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, 30332 GA, USA
- Department of Physics, University of California San Diego, 9500 Gilman Drive, La Jolla, 92093 CA, USA
| | - Eva-Maria S Collins
- Department of Biology, Swarthmore College, 500 College Ave, Swarthmore, 19081 PA, USA
- Department of Physics, University of California San Diego, 9500 Gilman Drive, La Jolla, 92093 CA, USA
- Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, 19104 PA, USA
| |
Collapse
|
4
|
de Lima FMR, Abrahão I, Pentagna N, Carneiro K. Gradual specialization of phagocytic ameboid cells may have impaired regenerative capacities in metazoan lineages. Dev Dyn 2023; 252:343-362. [PMID: 36205096 DOI: 10.1002/dvdy.543] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 09/20/2022] [Accepted: 09/30/2022] [Indexed: 11/08/2022] Open
Abstract
Animal regeneration is a fascinating field of research that has captured the attention of many generations of scientists. Among the cellular mechanisms underlying tissue and organ regeneration, we highlight the role of phagocytic ameboid cells (PACs). Beyond their ability to engulf nutritional particles, microbes, and apoptotic cells, their involvement in regeneration has been widely documented. It has been extensively described that, at least in part, animal regenerative mechanisms rely on PACs that serve as a hub for a range of critical physiological functions, both in health and disease. Considering the phylogenetics of PAC evolution, and the loss and gain of nutritional, immunological, and regenerative potential across Metazoa, we aim to discuss when and how phagocytic activity was first co-opted to regenerative tissue repair. We propose that the gradual specialization of PACs during metazoan derivation may have contributed to the loss of regenerative potential in animals, with critical impacts on potential translational strategies for regenerative medicine.
Collapse
Affiliation(s)
- Felipe Matheus Ribeiro de Lima
- Laboratory of Cellular Proliferation and Differentiation, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- Developmental Biology, Postgraduate Program in Morphological Sciences, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Isabella Abrahão
- Laboratory of Cellular Proliferation and Differentiation, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Nathalia Pentagna
- Laboratory of Cellular Proliferation and Differentiation, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- Postgraduate Program in Medicine (Pathological Anatomy), Faculty of Medicine, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Katia Carneiro
- Laboratory of Cellular Proliferation and Differentiation, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- Developmental Biology, Postgraduate Program in Morphological Sciences, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- Postgraduate Program in Medicine (Pathological Anatomy), Faculty of Medicine, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| |
Collapse
|
5
|
Abstract
The remarkable regenerative abilities of the small cnidarian Hydra vulgaris include the capacity to reassemble itself after dissociation into individual cells. Here, we present a robust protocol for the dissociation and reaggregation of Hydra tissue that addresses many common challenges encountered during the preparation and execution of the dissociation, as well as the formation and care of regenerating cellular aggregates. Analysis of the process provides insight into the mechanisms of nervous system self-organization. For complete details on the use and execution of this protocol, please refer to Lovas and Yuste (2021). Amplify experimental Hydra and prepare for the animal’s dissociation Dissociate Hydra into individual cells, aggregate, and monitor their reassembly Follow Hydra’s epithelial layer segregation and neural circuit formation A new polyp emerges from the cellular aggregate after one week of development
Publisher’s note: Undertaking any experimental protocol requires adherence to local institutional guidelines for laboratory safety and ethics.
Collapse
|
6
|
Cote LE, Feldman JL. Won’t You be My Neighbor: How Epithelial Cells Connect Together to Build Global Tissue Polarity. Front Cell Dev Biol 2022; 10:887107. [PMID: 35800889 PMCID: PMC9253303 DOI: 10.3389/fcell.2022.887107] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Accepted: 05/30/2022] [Indexed: 11/13/2022] Open
Abstract
Epithelial tissues form continuous barriers to protect against external environments. Within these tissues, epithelial cells build environment-facing apical membranes, junction complexes that anchor neighbors together, and basolateral surfaces that face other cells. Critically, to form a continuous apical barrier, neighboring epithelial cells must align their apico-basolateral axes to create global polarity along the entire tissue. Here, we will review mechanisms of global tissue-level polarity establishment, with a focus on how neighboring epithelial cells of different origins align their apical surfaces. Epithelial cells with different developmental origins and/or that polarize at different times and places must align their respective apico-basolateral axes. Connecting different epithelial tissues into continuous sheets or tubes, termed epithelial fusion, has been most extensively studied in cases where neighboring cells initially dock at an apical-to-apical interface. However, epithelial cells can also meet basal-to-basal, posing several challenges for apical continuity. Pre-existing basement membrane between the tissues must be remodeled and/or removed, the cells involved in docking are specialized, and new cell-cell adhesions are formed. Each of these challenges can involve changes to apico-basolateral polarity of epithelial cells. This minireview highlights several in vivo examples of basal docking and how apico-basolateral polarity changes during epithelial fusion. Understanding the specific molecular mechanisms of basal docking is an area ripe for further exploration that will shed light on complex morphogenetic events that sculpt developing organisms and on the cellular mechanisms that can go awry during diseases involving the formation of cysts, fistulas, atresias, and metastases.
Collapse
|
7
|
Rathbun LI, Everett CA, Bergstralh DT. Emerging Cnidarian Models for the Study of Epithelial Polarity. Front Cell Dev Biol 2022; 10:854373. [PMID: 35433674 PMCID: PMC9012326 DOI: 10.3389/fcell.2022.854373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Accepted: 03/01/2022] [Indexed: 11/13/2022] Open
Abstract
Epithelial tissues are vital to the function of most organs, providing critical functions such as secretion, protection, and absorption. Cells within an epithelial layer must coordinate to create functionally distinct apical, lateral, and basal surfaces in order to maintain proper organ function and organism viability. This is accomplished through the careful targeting of polarity factors to their respective locations within the cell, as well as the strategic placement of post-mitotic cells within the epithelium during tissue morphogenesis. The process of establishing and maintaining epithelial tissue integrity is conserved across many species, as important polarity factors and spindle orientation mechanisms can be found in many phyla. However, most of the information gathered about these processes and players has been investigated in bilaterian organisms such as C. elegans, Drosophila, and vertebrate species. This review discusses the advances made in the field of epithelial polarity establishment from more basal organisms, and the advantages to utilizing these simpler models. An increasing number of cnidarian model organisms have been sequenced in recent years, such as Hydra vulgaris and Nematostella vectensis. It is now feasible to investigate how polarity is established and maintained in basal organisms to gain an understanding of the most basal requirements for epithelial tissue morphogenesis.
Collapse
|
8
|
Suzuki S, Omori I, Kuraishi R, Kaneko H. Cell sorting and germ layer formation in reconstructed starfish embryos. Dev Growth Differ 2021; 63:343-353. [PMID: 34480340 DOI: 10.1111/dgd.12749] [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: 06/19/2021] [Revised: 07/22/2021] [Accepted: 07/28/2021] [Indexed: 11/28/2022]
Abstract
Germ layer formation is driven by embryonic cell sorting during the early developmental stages. Starfish (Patiria pectinifera) embryos have a connected endoderm and ectoderm, albeit with few contact surfaces between the epithelia. To better understand the association between cell sorting and germ layer formation, we reconstructed P. pectinifera embryos and examined their germ layer formation. Initial observations showed that the presumptive endodermal (pEN) and presumptive ectodermal (pEC) portions of the embryonic body at the late-blastula stage were preserved throughout development. Based on this, cells that were dissociated from each dermal fragment were mixed in a reconstruction experiment. Our results showed that the pEN and pEC cells were located inside and outside the reaggregates, respectively, to form an embryonic body containing two epithelial layers, separated by a blastocoel. During this process, the pEN cells were motile and shifted from smaller clumps to form a large clump. In contrast, in reaggregates formed in separate cultures, the pEN cells showed strong adhesion abilities, whereas the pEC cells underwent epithelialization. Unlike that in pEN cells, the reaggregation of pEC cells preceded cadherin expression. Filamentous actin was similarly observed in both reaggregates. These results suggest that during the reconstruction of starfish embryos, germ layer formation occurs via the sorting of pEN and pEC cells, depending on their adhesiveness, motility, and epithelialization. In vivo, these properties might embody the physiological significance of cell adhesion in the germ layers constituting the epithelial monolayer.
Collapse
Affiliation(s)
- Sohei Suzuki
- Department of Biosciences and Informatics, Faculty of Science and Technology, Keio University, Yokohama, Japan
| | - Ikuko Omori
- Department of Biosciences and Informatics, Faculty of Science and Technology, Keio University, Yokohama, Japan.,Department of Hematology, Nippon Medical School, Bunkyo-ku, Japan
| | - Ritsu Kuraishi
- Department of Biology, Research and Education Center for Natural Sciences, Keio University, Yokohama, Japan
| | - Hiroyuki Kaneko
- Department of Biology, Research and Education Center for Natural Sciences, Keio University, Yokohama, Japan
| |
Collapse
|
9
|
Abstract
Morphogenesis is one of the most remarkable examples of biological pattern formation. Despite substantial progress in the field, we still do not understand the organizational principles responsible for the robust convergence of the morphogenesis process across scales to form viable organisms under variable conditions. Achieving large-scale coordination requires feedback between mechanical and biochemical processes, spanning all levels of organization and relating the emerging patterns with the mechanisms driving their formation. In this review, we highlight the role of mechanics in the patterning process, emphasizing the active and synergistic manner in which mechanical processes participate in developmental patterning rather than merely following a program set by biochemical signals. We discuss the value of applying a coarse-grained approach toward understanding this complex interplay, which considers the large-scale dynamics and feedback as well as complementing the reductionist approach focused on molecular detail. A central challenge in this approach is identifying relevant coarse-grained variables and developing effective theories that can serve as a basis for an integrated framework for understanding this remarkable pattern-formation process. Expected final online publication date for the Annual Review of Cell and Developmental Biology, Volume 37 is October 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
Collapse
Affiliation(s)
- Yonit Maroudas-Sacks
- Department of Physics, Technion-Israel Institute of Technology, Haifa 32000, Israel;
| | - Kinneret Keren
- Department of Physics, Technion-Israel Institute of Technology, Haifa 32000, Israel; .,Network Biology Research Laboratories and The Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 32000, Israel
| |
Collapse
|
10
|
Dickinson DJ. Tissue Morphogenesis: A Cellular View of Adhesion-Dependent Cell Sorting. Curr Biol 2020; 30:R1071-R1073. [PMID: 33022235 DOI: 10.1016/j.cub.2020.07.071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Cells from different germ layers - endoderm, mesoderm and ectoderm - can spontaneously segregate within a cell aggregate, and differential cell-cell adhesion has been proposed to explain this behavior. New observations at subcellular resolution suggest a more nuanced view.
Collapse
Affiliation(s)
- Daniel J Dickinson
- Department of Molecular Biosciences, University of Texas at Austin, 2415 Speedway, Austin, TX 78712, USA.
| |
Collapse
|