Cell tracking supports secondary gastrulation in the moon jellyfish Aurelia
Abstract
The moon jellyfish Aurelia exhibits a dramatic reorganization of tissue during its metamorphosis from planula larva to polyp. There are currently two competing hypotheses regarding the fate of embryonic germ layers during this metamorphosis. In one scenario, the original endoderm undergoes apoptosis and is replaced by a secondary endoderm derived from ectodermal cells. In the second scenario, both ectoderm and endoderm remain intact through development. In this study, we performed a pulse-chase experiment to trace the fate of larval ectodermal cells. We observed that prior to metamorphosis, ectodermal cells that proliferated early in larval development concentrate at the future oral end of the polyp. During metamorphosis, these cells migrate into the endoderm, extending all the way to the aboral portion of the gut. We therefore reject the hypothesis that larval endoderm remains intact during metamorphosis and provide additional support for the "secondary gastrulation" hypothesis. Aurelia appears to offer the first and only described case where a cnidarian derives its endoderm twice during normal development, adding to a growing body of evidence that germ layers can be dramatically reorganized in cnidarian life cycles.
Additional Information
© 2016 Springer-Verlag Berlin Heidelberg. Received: 24 April 2016; Accepted: 09 August 2016; First Online: 18 August 2016. This work was supported by funding from the NASA Astrobiology Institute (NNA13AA90A) Foundations of Complex Life, Evolution, Preservation, and Detection on Earth and Beyond.Additional details
- Eprint ID
- 69805
- DOI
- 10.1007/s00427-016-0559-y
- Resolver ID
- CaltechAUTHORS:20160822-082834278
- NNA13AA90A
- NASA
- Created
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2016-08-22Created from EPrint's datestamp field
- Updated
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2021-11-11Created from EPrint's last_modified field