4 Rapunzel , A Novel Zebrafish Mutant with Loss of Nutrition-Dependent Growth Control

Background and Purpose of Study: The essential genetics of normal human growth are not well understood. Size and form are maintained through the appropriate coordination of isometric and allometric growth. In addition, humans must be able to adapt their nascent developmental programs, such as growth, to ever changing environmental conditions, including nutritional status. When isometric or allometric control of growth is lost, disorders of growth control including overgrowth, undergrowth and cancer ensue. We use zebrafish and in particular, the zebrafish fin, as a genetically and physiologically tractable model to dissect the biology of growth control. Growth of the adult zebrafish caudal fin is episodic and isometric. In addition, when adult zebrafish are fasted, checkpoints rapidly abrogate caudal fin growth.