13-P005 Tbx1 controls cardiac neural crest cell migration during arch artery development by regulating Gbx2 expression in the pharyngeal ectoderm

The way in which organisms generate patterns of differentiated tissues is of fundamental interest to developmental biology. One way to do this involves the formation of pattern without positional information and is fascinating because it raises the question of how cells can adopt different fates within a uniform environment. We are using the social amoeba, D. discoideum to show that it is the relative sensitivity of cells to inducing signals within the developing system that is important in making initial cell fate choice decisions in uniform environments. We show that relative levels of Ras activation are important in determining the sensitivity of cells to inducing signals during development and that this sensitivity is further modulated by differences in glucose metabolism between cells. Understanding the mechanisms by which Ras regulation and glucose metabolism interact to affect sensitivity to signals will provide valuable insight into the mechanisms that allow organisms to pattern without positional information