29.01.2020: Christoph Hahn, PhD (Graz): Genomic insights into the evolution of obligate parasitic flatworms (Neodermata, Platyhelminthes), Institut für Biologie, Bereich für Zoologie, Universitätsplatz 2, HS 02.11, 13:15 Uhr.
The Neodermata (Platyhelminthes) are a highly diverse assemblage of obligate parasitic flatworms, comprising Cestoda (tapeworms), Monogenea, and Trematoda (flukes), many of biomedical, veterinary and economic importance. Together, they span an impressive range of hosts and parasitic lifestyles. With their simple, direct life cycles, monogeneans are key for understanding the shift towards obligate parasitism of vertebrates, the evolutionary history of ecto- and endoparasitism, and the emergence of complex life cycles in Neodermata. Despite decades of research, however, the relationships between the main parasitic lineages remain contentious.
I will present first results from the project "Deep Evolutionary Genomics of Monogenea", which has recently been funded by the FWF and represents a large international collaborative effort currently supported by a consortium of Monogenea experts from 15 countries and 17 research institutions. The project aims, by means of extensive taxon sampling, whole genome sequencing and cutting edge bioinformatic/phylogenomic methods, to: (i) elucidate the phylogenetic position of the Monogenea and thus the origins of vertebrate parasitism within Platyhelminthes, (ii) infer the interrelationships of Monogenea and test hypotheses of deep evolutionary host-parasite interactions, and (iii) identify genomic features associated with the diverse parasitic life history strategies employed by the Monogenea, and Neodermata in general.
In a second part, I focus on Gyrodactylus salaris, a notorious pathogen of salmonids and arguably the best studied monogenean on the planet. The species comprises a number of genetic lineages that differ with respect to biological traits such as pathogenicity and host specificity. We investigate the genetic bases of these traits based on whole-genome sequencing (WGS) data obtained for isolates from five host species.