Reddien Lab: Planarian Regeneration

The ability of organisms to regenerate missing body parts is one of the great mysteries of biology. Planarians are freshwater invertebrates that have been a classic regeneration model for over a century. The regenerative abilities of planarians astound: following decapitation, a new head can be regenerated in under a week and an entire animal can be regenerated from a body fragment approximately 1/300th the size of the original animal. Regeneration involves formation of an outgrowth of tissue at wound sites (a blastema) that produces missing tissues.Because planarian regeneration involves a population of adult pluripotent stem cells (the neoblasts), planarians are excellent organisms for in vivo studies of how stem cells can be regulated to replace aged, damaged, and missing tissues. Because more than 50% of examined planarian genes have human counterparts, genetic study of neoblasts stands to impact our understanding of human stem cell biology.

The development of planarian RNA interference (RNAi) screening methodologies has set the stage for molecular, genetic characterization of regeneration. We aim to understand how neoblasts are regulated to bring about the regeneration of missing tissues. The approach involves study of our identified regeneration regulatory genes and continued usage of our developed RNAi-screening approaches.