Alejandro Sanchez Alvarado, Ph.D.
Department of Neurobiology and Anatomy, University of Utah
Planarians, Stem Cells, and Regeneration
Under normal physiological conditions, the functions of many organs depend on the continuous destruction and renewal of their cells. Equally remarkable is the fact that the adult tissues and organs of many organisms can be fully restored after amputation. In fact, metazoans have evolved a series of renewal and repair mechanisms to respond to both trauma and normal wear and tear. Such mechanisms are under tight regulatory control such that the form and function of tissues, organs, and systems can be maintained throughout life. As important as repair and restoration are to the survival of multicellular organisms, we know little about how these processes are effected and regulated at the cellular and molecular levels. Here, I will discuss how the study of a simple metazoan, the planarian Schmidtea mediterranea, is beginning to shed light on the way adult animals regulate tissue homeostasis and the replacement of body parts lost to injury.