Regeneration in the Pilidium

Abstract

Ability to regenerate is found in many groups of metazoans but the majority of research is focused on adults from just a few taxa, such as planarians and hydra (Agata and Inoue, 2012; Bely et al., 2014). Increasing the diversity of study organisms and life stages can reveal new and interesting aspects of regeneration mechanisms. This study focuses on regeneration of the nemertean pilidium larva. The planktotrophic pilidium of Maculaura alaskensis provides a unique model in which to observe several components of the regeneration process. Here I have documented a timeline for regeneration and have begun to evaluate the cells responsible for regenerative success. This study has revealed the interplay between regeneration and degeneration, a tradeoff between larval and juvenile structures, as well as the important relationship between global versus local signaling in proliferation and differentiation responses.