The Science Seminar Series: Octpober 29, 2009
Parasitic Genomes On the Move: A Study of Genome Rearrangement in the Phylum Apicomplexa
Department of Biology
University of Georgia
Time: 4:00 -5:00pm
The eukaryotic phylum Apicomplexa contains many obligate intracellular parasites responsible for a wide range of both human and veterinary diseases (e.g. Malaria, Toxoplasmosis, and Theileriosis). The recent availability of annotated genome sequence data for important members of the phylum facilitates detailed comparative genomics studies. Such studies can be utilized for the discovery of the mechanisms underlying genome evolution, leading to a better understanding of the relationships between both the members within the Apicomplexa as well as between the parasites and their hosts. We have developed a gene-marker based bioinformatics pipeline to investigate genome rearrangement of 11 Apicomplexan species across 6 genera. Rearrangement between genera is extremely extensive. Conserved regions are rare between genera and appear to be totally absent between all species. This is especially surprising considering the apparent absence of transposable elements (TEs), (DNA sequences with the ability to mobilize and increase their copy number in a genome), within any of the species examined. TEs are ubiquitous in all other groups of eukaryotes studied to date, and have been shown to be the primary agents responsible for genomic rearrangements in many species. Based on these observations, it appears that there may be a different set of criteria governing genome evolution in the Apicomplexa, relative to other eukaryotes.