Functional Genomics of Larval Development, Metamorphosis and Settlement in Aplysia californica
The sea hare Aplysia californica has been used extensively as a model system to understand physiological and cellular mechanisms underlying learning and memory. Still, molecular mechanisms underlying these processes have been, until recently, poorly understood. Large scale sequencing projects including the Aplysia neuronal transcriptom (Moroz et al. 2006) and the Aplysia genome (to be announced) have significantly contributed to our understanding of how these fundamental processes in the Aplysia function on a molecular level. In collaboration with Dr. Leonid Moroz (University of Florida), my lab is focusing on expanding our understanding about the mechanisms underlying the development of the Aplysia central nervous system and its modifications during larval development and specifically metamorphosis. Using functional genomics tools such as microarrays, in situ hybridizations and functional gene knockouts in the sea hare we 1) identify key regulatory nodes in the gene regulatory network patterning the Aplysia CNS (central nervous system) and 2) identify target genes involved in specific behavioral changes which occur during the metamorphic transition such as changes in feeding and locomotion. Using this approach we were able to identify novel neuropeptides and nuclear hormone receptors, potentially involved in the regulation of early development and the metamorphic transition of Aplysia californica. Moreover we gained new insights into the development and function of the neuroendocrine system of the sea hare. To this end we are validating these targets and functionally test them in both development and the mature CNS.