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van Drongelen R, Vazquez-Faci T, Huijben TAPM, van der Zee M, Idema T. Mechanics of epithelial tissue formation. J Theor Biol 2018; 454:182-189. [PMID: 29883740 DOI: 10.1016/j.jtbi.2018.06.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Revised: 05/31/2018] [Accepted: 06/03/2018] [Indexed: 01/06/2023]
Abstract
A key process in the life of any multicellular organism is its development from a single egg into a full grown adult. The first step in this process often consists of forming a tissue layer out of randomly placed cells on the surface of the egg. We present a model for generating such a tissue, based on mechanical interactions between the cells, and find that the resulting cellular pattern corresponds to the Voronoi tessellation of the nuclei of the cells. Experimentally, we obtain the same result in both fruit flies and flour beetles, with a distribution of cell shapes that matches that of the model, without any adjustable parameters. Finally, we show that this pattern is broken when the cells grow at different rates.
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Affiliation(s)
- Ruben van Drongelen
- Department of Bionanoscience, Kavli Institute of Nanoscience, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlands
| | - Tania Vazquez-Faci
- Department of Bionanoscience, Kavli Institute of Nanoscience, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlands; Institute of Biology, Leiden University, Sylviusweg 72, Leiden 2333 BE, The Netherlands
| | - Teun A P M Huijben
- Department of Bionanoscience, Kavli Institute of Nanoscience, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlands
| | - Maurijn van der Zee
- Institute of Biology, Leiden University, Sylviusweg 72, Leiden 2333 BE, The Netherlands
| | - Timon Idema
- Department of Bionanoscience, Kavli Institute of Nanoscience, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlands.
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van der Zee M, Benton MA, Vazquez-Faci T, Lamers GEM, Jacobs CGC, Rabouille C. Innexin7a forms junctions that stabilize the basal membrane during cellularization of the blastoderm in Tribolium castaneum. Development 2015; 142:2173-83. [DOI: 10.1242/dev.097113] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2013] [Accepted: 04/21/2015] [Indexed: 01/24/2023]
Abstract
In insects, the fertilized egg undergoes a series of rapid nuclear divisions before the syncytial blastoderm starts to cellularize. Cellularization has been extensively studied in Drosophilamelanogaster, but its thick columnar blastoderm is unusual among insects. We therefore set out to describe cellularization in the beetle Tribolium castaneum, the embryos of which exhibit a thin blastoderm of cuboidal cells, like most insects. Using immunohistochemistry, live imaging and transmission electron microscopy, we describe several striking differences to cellularization in Drosophila, including the formation of junctions between the forming basal membrane and the yolk plasmalemma. To identify the nature of this novel junction, we used the parental RNAi technique for a small-scale screen of junction proteins. We find that maternal knockdown of Triboliuminnexin7a (Tc-inx7a), an ortholog of the Drosophila gap junction gene Innexin 7, leads to failure of cellularization. In Inx7a-depleted eggs, the invaginated plasma membrane retracts when basal cell closure normally begins. Furthermore, transiently expressed tagged Inx7a localizes to the nascent basal membrane of the forming cells in wild-type eggs. We propose that Inx7a forms the newly identified junctions that stabilize the forming basal membrane and enable basal cell closure. We put forward Tribolium as a model for studying a more ancestral mode of cellularization in insects.
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Affiliation(s)
- Maurijn van der Zee
- Hubrecht Institute for Developmental Biology and Stem Cell Research, Uppsalalaan 8, Utrecht 3584 CT, The Netherlands
- Institute of Biology, Leiden University, Sylviusweg 72, Leiden 2333 BE, The Netherlands
| | - Matthew A. Benton
- Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK
| | - Tania Vazquez-Faci
- Institute of Biology, Leiden University, Sylviusweg 72, Leiden 2333 BE, The Netherlands
| | - Gerda E. M. Lamers
- Institute of Biology, Leiden University, Sylviusweg 72, Leiden 2333 BE, The Netherlands
| | - Chris G. C. Jacobs
- Institute of Biology, Leiden University, Sylviusweg 72, Leiden 2333 BE, The Netherlands
| | - Catherine Rabouille
- Hubrecht Institute for Developmental Biology and Stem Cell Research, Uppsalalaan 8, Utrecht 3584 CT, The Netherlands
- Department of Cell Biology, UMC Utrecht, 3584 CX Utrecht, The Netherlands
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