Test cells ofAscidiella aspersa:Adhesion and migration behaviour during embryogenesis
作者:
BIRGIT LÜBBERING,
EVA NIERMANN-KERKENBERG,
DIETRICHKURT HOFMANN,
期刊:
Invertebrate Reproduction & Development
(Taylor Available online 1992)
卷期:
Volume 21,
issue 3
页码: 241-252
ISSN:0792-4259
年代: 1992
DOI:10.1080/07924259.1992.9672243
出版商: Taylor & Francis Group
数据来源: Taylor
摘要:
During the tail-bud stage ofAscidiella aspersaembryogenesis, the test cells or innermost cells of the egg envelope manifest locomotive activities. Light microscopy further reveals that the adhesive behaviour of test cells changes in the course of embryogenesis. Mechanical dechorionation experiments performed on 846 embryos demonstrate that up to the tail-bud stage all test cells are attached to the inner surface of the chorion. The embryo is completely devoid of test cells. At the onset of larval tunic secretion, increasing numbers of test cells settle on the embryo until all test cells adhere to it. This switch in adhesive properties is completed within 65 min. The hatched larva carries the entire complement of test cells until the onset of metamorphosis. SEM and observations show that test cells do not establish direct cell-to-cell contacts to ectodermal cells but attach to the larval tunic.
点击下载:
PDF (4709KB)
返 回