Motility of endodermal epithelial cells plays a major role in reorganizing the two epithelial layers in Hydra

نویسندگان

  • Yasuharu Takaku
  • Takahiko Hariyama
  • Toshitaka Fujisawa
چکیده

Cell-cell interactions and cell rearrangements play important roles during development. Aggregates of Hydra cells reorganize into the two epithelial layers and subsequently form a normal animal. Examination of the formation of the two layers under various situations, indicates that the motility of endodermal epithelial cells, but not the differential adhesive forces of the two types of epithelial cells, plays the critical role in setting up the two epithelial layers. (1) When aggregates of ectodermal cells and of endodermal cells were placed in direct contact, the endodermal cells migrated into the interior of the ectodermal aggregate. This process was completely inhibited by cytochalasin B although initial firm attachment between the two aggregates was not blocked. (2) A single endodermal epithelial cell placed in contact with an ectodermal aggregate, actively extended pseudopod-like structures and migrated toward the center of the ectodermal aggregate. In contrast, an ectodermal epithelial cell remained in contact with an endodermal aggregate and never exhibited migratory behavior. Cytochalasin treatment of only endodermal epithelial cells abolished the migration. (3) One to 4 endodermal epithelial cells and/or ectodermal epithelial cells were placed in contact with one another forming up to 4-cell aggregates. Endodermal epithelial cells exhibited high motility that can be attributed to the migratory movement described above. Finally, formation of actin bundles, as visualized with rhodamine-phalloidin, was always correlated with pseudopod formation in endodermal epithelial cells during early and mid stages of aggregate formation.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Hydra regeneration from recombined ectodermal and endodermal tissue. II. Differential stability in the ectodermal and endodermal epithelial organization.

Hydra tissue consists of the ectodermal and the endodermal layers. When the two layers were separated by procaine treatment and then recombined, the ectodermal epithelial cells spread as a single cell layer over the endoderm as in epiboly in vertebrate embryogenesis, and the resultant spherical structure subsequently regenerated into a complete hydra. In this study, light and electron microscop...

متن کامل

Hydra regeneration from recombined ectodermal and endodermal tissue. I. Epibolic ectodermal spreading is driven by cell intercalation.

Cell-cell interaction and cell rearrangement were examined in the process of epithelial sheet formation during regeneration from hydra cell aggregates. The ectodermal and endodermal epithelial cell layers of Hydra magnipapillata were separated by procaine treatment. Each of the separated layers was then dissociated into single cells and reaggregated to produce ectodermal or endodermal cell aggr...

متن کامل

Epithelial interactions in Hydra: apoptosis in interspecies grafts is induced by detachment from the extracellular matrix.

Apoptosis plays an important role in immunity and is widely used to eliminate foreign or infected cells. Cnidaria are the most basal eumetazoans and have no specialised immune cells, but some colonial cnidarians possess a genetic system to discriminate between self and non-self. By grafting epithelia of different species we have previously shown that the freshwater polyp Hydra eliminates non-se...

متن کامل

Effect of Matrigel on Function and Morphology of Human Endometrial Epithelial Cell in vitro

The importance of extra cellular matrix (ECM) in development and function of different cells has been reported but little is known about its role in human endometrial epithelial cells. The aim of the present study was to examine effects of artificial ECM (Matrigel) and progesterone on the function and morphology of human endometrial epithelial cells in vitro. Methods: Endometrial samples were ...

متن کامل

Apical and basal epitheliomuscular F-actin dynamics during Hydra bud evagination

Bending of 2D cell sheets is a fundamental morphogenetic mechanism during animal development and reproduction. A critical player driving cell shape during tissue bending is the actin cytoskeleton. Much of our current knowledge about actin dynamics in whole organisms stems from studies of embryonic development in bilaterian model organisms. Here, we have analyzed actin-based processes during ase...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • Mechanisms of Development

دوره 122  شماره 

صفحات  -

تاریخ انتشار 2005