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Интеллектуальная Система Тематического Исследования НАукометрических данных |
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Gastrulation mechanisms in Dynamena pumila (Cnidaria: Hydrozoa)тезисы доклада Тезисы
- Авторы: Vetrova A.A., Bagaeva T.S., Saidova A.A., Kupaeva D.M., Kraus Y.A., Kremnyov S.V.
- Сборник: Беломорская студенческая научная сессия СПбГУ — 2020. Тезисы докладов
- Тезисы
- Год издания: 2020
- Место издания: Свое издательство Санкт-Петербург Санкт-Петербург
- Первая страница: 58
- Последняя страница: 58
- Аннотация: Cnidarians display almost the full range of existing gastrulation modes, which can be modified and combine witheach other in different ways. In the development of colonial hydroid Dynamena pumila the unique way of gastrulationcan be observed. Morular delamination is the principal mode of gastrulation in D. pumila and proceeds through severalsteps. At the first step of gastrulation, epithelial sheet fragments start to form simultaneously at the several regions of theembryo surface. At the second step, epithelial sheet fragments join and fuse via active planar cell movements, when cellsfrom different epithelization regions form contacts with each other through filopodia and get closer, contracting them.Convergence of epithelial fragments lead to the formation of multiple toroidal-like structures. At the last step ofgastrulation, holes of toroidal surfaces close basically according to the same mechanism as the merging of epithelial sheetfragments earlier. Upon tori closure, initially outer cells forming the bottom of torus passively submerge inside theembryo, where they may contribute to the endoderm.Some surface cells of the embryo take a bottle-like shape during morula and early gastrula stages. Perhaps, thesecells migrate inside the embryo and join the endoderm population. In this case, it can be assumed that ingression is oneof the mechanisms of gastrulation in D. pumila. Cells also can get inside, when some outer cells divide perpendicularlyto the surface of the embryo at the morula stage, which looks similar to the mechanism of cellular delamination.Mechanisms of epithelial sheet fragments merging and tori closure resembles the processes occurring duringwound healing in embryonic and adult tissues and epithelium formation in the embryogenesis of higher Metazoa. Thus,it is assumed that in the center of the epithelial tori the integrity of the epithelial layer is broken, and it should be restoredduring their “healing”.In sum, gastrulation in D. pumila proceeds in an apolar fashion by a mixed delamination, probably accompaniedby multipolar cell ingression.The study was supported by grant from RFBR No 17-04-01988а.
- Добавил в систему: Кремнёв Станислав Валерьевич