General sessions3B-12 Genome sequencing project of a choanoflagellate, Monosiga ovata: I. Genome structure

All extant animals are multicellular organisms that consist of many different types of cells. It is very important to understand the relationship between the evolution of metazoan multicellu-larity and the diversification of gene family members involved in cell-cell communication and developmental controls of animals, although it is difficult to do. Recent molecular phylogenetic studies suggested that choanoflagellate is one of the closest living unicellular protists of metazoans. Therefore, genome-wide sequence analysis with choanoflagellates and many animals is very important for understanding the evolution of metazoan multicellularity. Our research group has recently sequenced the genome of a choanoflagellate, Monosiga ovata. The genome size of M.ovata is about 64 Mb, and the G+C content is 58.5%. The number of protein-coding genes in the genome is estimated to be about 20,000.