COLBOURNE, J.K.*; LINDQUIST, E.; BAUER, D.; BROKSTEIN, P.; THOMAS, W.K.; ANDREWS, J.; Center for Genomics and Bioinformatics, Indiana University; U.S. Department of Energy, Joint Genome Institute; Hubbard Center for Genome Studies, University of New Hampshire; U.S. Department of Energy, Joint Genome Institute; Hubbard Center for Genome Studies, University of New Hampshire; Center for Genomics and Bioinformatics, Indiana University: Gene discovery in Daphnia by expressed sequence tag sequencing

The Daphnia genome project is a consortium based endeavor to characterize the genome and transcriptome of a crustacean and to generate resources for genomic studies in the fields of ecology, toxicology and evolution. To facilitate the annotation of the genome sequence and to accelerate the production of a full transcriptome microarray, we created unidirectional cDNA libraries from Daphnia exposed to 12 distinct ecological stressors ranging from toxic metals and UV radiation to hypoxia, starvation and predation. We are sequencing 5� and 3� EST sequence reads from randomly selected clones from each library. At the mid-point in the project, we identified over 12,600 unique genes from 71,000 high quality ESTs. These gene sequences were queried, using a variety of homology searches, against those from other arthropod genomes to discover their evolutionary conservation with respect to putative gene functions. This genome-wide comparative analysis of Daphnia genes with the functionally well characterized genes of model insects provides important findings into similarities / differences between these two classes of Arthropoda and provides clues into the biology of a fascinating sentinel species within freshwater habitats.