HEYLAND, Andreas*; MOROZ, Leonid/L; The Whitney Laboratory for Marine Bioscience, Saint Augustine, FL; Department of Neuroscience, University of Florida, FL; The Whitney Laboratory for Marine Bioscience, Saint Augustine, FL; Department of Neuroscience, University of Florida, FL: SEARCH FOR NEURONAL TRANSCRIPTS INVOLVED IN THE METAMORPHIC TRANSITION OF THE SEA HARE APLYSIA CALIFORNICA

Metamorphosis among many marine invertebrate species involves a radical transition from a larval to a juvenile/adult body plan that can occur in a remarkably short period of time. Metamorphic competence directly precedes this radical change in morphology and can best be described as the developmental potential of a larva to undergo the radical transition in response to environmental signals. Such signals (i.e. settlement cues, substrate architecture, temperature, food etc.) are modulated via neuronal gene networks. A metamorphic pattern with competence and a fast radical transformation evolved many times independently in animals and we hypothesize that similar signaling modules have been co-opted for the regulation of a) the development to competence and b) the interpretation and modulation of environmental signals. However the actual signaling architecture underlying these processes is largely unknown for the majority of marine invertebrate species. We used representative oligo-arrays constructed from transcripts obtained from the Aplysia californica (sea hare, Mollusca) central nervous system to explore the following two questions: 1) What neuron specific genes are expressed during development to metamorphic competence? 2) What neuron specific genes are expressed immediately after settlement, i.e. upon exposure to specific environmental signals. We validated our expression analysis of specific neuropeptides, nuclear hormone receptors and chemoreceptor molecules using in situ hybridizations. Support Contributed By: NIH, NSF, & McKnight BR Foundation.