Regeneration of the gut requires retinoic acid in the budding ascidian Polyandrocarpa misakiensis
Article first published online: 25 MAY 2010
© 2010 The Authors. Journal compilation © 2010 Japanese Society of Developmental Biologists
Development, Growth & Differentiation
Volume 52, Issue 5, pages 457–468, June 2010
How to Cite
Kaneko, N., Katsuyama, Y., Kawamura, K. and Fujiwara, S. (2010), Regeneration of the gut requires retinoic acid in the budding ascidian Polyandrocarpa misakiensis. Development, Growth & Differentiation, 52: 457–468. doi: 10.1111/j.1440-169X.2010.01184.x
- Issue published online: 25 MAY 2010
- Article first published online: 25 MAY 2010
- Received 25 February 2010; revised 26 March 2010; accepted 26 March 2010.
- retinoic acid;
The protochordate ascidian Polyandrocarpa misakiensis has a striking ability to regenerate. When the posterior half of the adult body is amputated, the anterior half completely loses the esophagus, stomach and intestine. These organs are reconstituted in a week. Histological observation revealed that the regeneration involves transdifferentiation of the atrial epithelium near the cut surface. The morphological features of the gut primordium were similar to those observed in the developing bud of this species. Inhibitors of the synthesis of retinoic acid (RA) suppressed the formation of the gut. 13-cis RA rescued the regenerates from the inhibitor-induced hypoplasia. These results suggest that RA is required for the regeneration of the gut. A gene encoding the RA receptor (Pm-RAR) and its target gene, TRAMP, were expressed in and around the regenerating gut. Pm-RAR-specific and TRAMP-specific double-stranded RNA molecules inhibited the regeneration of the gut, indicating that the RA signal is mediated at least in part by Pm-RAR and TRAMP. These results suggested that RA triggers the transdifferentiation of the atrial epithelium into the gut in regenerating animals, as it does during asexual reproduction.