caa a22 4500 475768337 CHVBK 20180406123612.0 cr unu---uuuuu 170329e20000101xx s 000 0 eng 10.1007/s004270050015 doi (NATIONALLICENCE)springer-10.1007/s004270050015 Tension-dependent collective cell movements in the early gastrula ectoderm of Xenopus laevis embryos [Elektronische Daten] [L. V. Beloussov, N. N. Louchinskaia, A. A. Stein] Abstract : Ventral ectodermal explants taken from early gastrula embryos of Xenopus laevis were artificially stretched either by two opposite concentrated forces or by a distributed force applied to the internal explant's layer. These modes of stretching reflect different mechanical situations taking place in the normal development. Two main types of kinematic response to the applied tensions were detected. First, by 15 min after the onset of concentrated stretching a substantial proportion of the explant's cells exhibited a concerted movement towards the closest point of the applied stretching force. We define this movement as tensotaxis. Later, under both concentrated and distributed stretching, most of the cell's trajectories became reoriented perpendicular to the stretching force, and the cells started to intercalate between each other, both horizontally and vertically. This was accompanied by extensive elongation of the outer ectodermal cells and reconstruction of cell-cell contacts. The intercalation movements led first to a considerable reduction in the stretch-induced tensions and then to the formation of peculiar bipolar ”embryoid” shapes. The type and intensity of the morphomechanical responses did not depend upon the orientation of a stretching force in relation to the embryonic axes. We discuss the interactions of the passive and active components in tension-dependent cell movements and their relations to normal morphogenetic events. Springer-Verlag Berlin Heidelberg, 2000 Key words Morphogenetic movements nationallicence Mechanical stresses nationallicence Cell intercalation nationallicence Xenopus laevis nationallicence Beloussov L. V. Department of Embryology, Faculty of Biology, Moscow State University Moscow 119899 Russia E-mail: lbelous@soil.msu.ru Tel.: +7-95-9393915, Fax: +7-95-9394309, RU aut Louchinskaia N. N. Department of Embryology, Faculty of Biology, Moscow State University Moscow 119899 Russia E-mail: lbelous@soil.msu.ru Tel.: +7-95-9393915, Fax: +7-95-9394309, RU aut Stein A. A. Institute of Mechanics, Moscow State University, Moscow 119899 Russia, RU aut https://doi.org/10.1007/s004270050015 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s004270050015 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Beloussov L. V. Department of Embryology, Faculty of Biology, Moscow State University Moscow 119899 Russia E-mail: lbelous@soil.msu.ru Tel.: +7-95-9393915, Fax: +7-95-9394309, RU aut NATIONALLICENCE 700 1- Louchinskaia N. N. Department of Embryology, Faculty of Biology, Moscow State University Moscow 119899 Russia E-mail: lbelous@soil.msu.ru Tel.: +7-95-9393915, Fax: +7-95-9394309, RU aut NATIONALLICENCE 700 1- Stein A. A. Institute of Mechanics, Moscow State University, Moscow 119899 Russia, RU aut Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer