Postcards from the edge

The publication of the mouse and human genomes enables comparative genomics to elucidate gene structure and function within these organisms, classed together within the Metazoa. To find the same functional and evolutionary information for animals in general, it is necessary to expand the comparison beyond the Metazoan lineage. In the July 18 Science, Nicole King and colleagues at the Howard Hughes Medical Institute report in silico investigations into the expressed sequence tags (ESTs) of the next most closely related lineage of eukaryotes to the Metazoa—the choanoflagellates. These investigations reveal those genes that existed before animals evolved into the multicellular organisms we see today (Science, 301:361-363, July 18, 2003).

King et al. analyzed more than 5000 ESTs from two choanoflagellate species and determined the phylogenetic distribution of the proteins or domains within eukaryotes, bacteria, archaea, and viruses. They then looked within the eukaryotes for distribution among non-animals including fungi and plants ...