Sequencing of the Ephydatia muelleri genome: preliminary results

With their unique evolutionary position of arguably the simplest extant and earliest branching metazoans, sponges are rapidly gaining focus in genomic research. Only one draft genome sequence of a sponge has been published to date, that of Amphimedon queenslandica. Genomic information from additional taxa is required for comparative genomic approaches within the phylum Porifera to describe their genomic makeup, gene architecture and structure, eventually leading to elucidation of early metazoan gene regulation and development. We sequenced and assembled a preliminary draft of the genome of the freshwater sponge Ephydatia muelleri using next-generation sequencing technology. Paired- end Illumina libraries yielded contigs covering at least 85% of the genome. Addition of SOLiD mate-pair libraries produced scaffolds covering the entire genome. We identified a preliminary gene set through automated annotation and functionally classified them using the STRING Clusters of Orthologous Groups (COG) database. Further sequencing is currently underway to improve coverage and complete the genome.