Project description:The marine mollusc Aplysia is a well established experimental system for cellular and systems neuroscience because of the relatively simple organization of its nervous system and the presence within it of the largest nerve cells in the animal kingdom, many of which are uniquely identifiable in every member of the species. Until now, molecular analyses of Aplysia have been seriously handicapped by lack of adequate genomic information, with only 200 sequences publicly available when this project was initiated in 2003. By sequencing cDNA libraries from the central nervous system, we have identified over 175,000 ESTs (expressed sequence tags), of which 19,814 are unique neuronal gene products and 9469 has been annotated. Through comparison with the complete genomic data available for Drosophila and C. elegans, we estimate that we have sequence information for approximately 50-70% of the total transcriptome of the Aplysia nervous system. We also identified 9,223 unique gene products in a modulatory serotonergic cell and about 1,000 unique gene products from its processes. Using gene expression oligoarrays constructed using the Aplysia EST database we also have characterized the transcript profile of sensory and motor neurons. In addition to increasing the amount of publicly available gene sequences of Aplysia by two orders of magnitude, this collection of transcripts is distinctive from a comparative biology point of view. It represents the largest database available for any member of the Lophotrochozoa clade of the animal kingdom. These molecular resources should allow the detailed study of the genomics of identified cells and circuits and provide in Aplysia a much needed bridge between genes, behavior, and learning. This SuperSeries is composed of the SubSeries listed below.
