Patterning embryos and healing adults : analysis of cnidarian development at different life cycle stages

Abstract

The primary goal of the following dissertation was to gain a greater understanding to the origins of animal diversity. Key transitions like the emergence of triploblasty and Hox genes are thought to be crucial innovations that allowed for the radiation of bilaterians. Using early animals such as placozoans and cnidarians, the following dissertation aims at understanding developmental phenomenon associated with patterning embryogenesis and regeneration. This study looks at the evolution, timing of activation and function of the first Hox genes in relation to different stages of development. These findings suggest that the first Hox genes likely patterned aspects of early development rather than the late developmental role often compared in bilaterians. In this dissertation, these results are compared with new evidence as to how placozoans pattern their adult body form and the emergence of anterior-posterior and dorsal-ventral patterning. Finally, this study describes the molecular and cellar processes involved with cnidarian wound healing. These results provide insight into how to initiate a regenerative response and may provide clues as to why regeneration is lost in many bilaterian lineages.