Planarian Regeneration: a Classic Model Enters the Era of Functional Genomics

Phil Newmark

Department of Cell and Structural Biology University of Illinois

Freshwater planarians- classic models of regeneration experiments- can regenerate complete animals from tiny fragments of their bodies. This remarkable plasticity is based upon a stem cell population present in the adult flatworm. These stem cells are used both to replace cells lost during the course of cell turnover and to regenerate missing structures when the animal is transected. Although the planarian\'s regenerative abilities have been known for over two centuries, the mechanisms underlying its remarkable developmental plasticity remain obscure. Recent work has sought to revive the study of this classic model organism, utilizing the powerful tools of molecular biology that were not available during the heyday of planarian research. This talk will describe recent technical advances that permit the molecular dissection of regeneration in planarians. Current work, aimed at using planarians to identify genes required for the control of stem cell proliferation and differentiation, as well as the epigenetic specification of germ cell fate, will also be outlined.