Intra-host interactions of Bacillus thuringiensis strains and their impact on experimental coevolution with Caenorhabditis elegans

CLUSTER: „Experimental evolution and natural variation of Bacillus-invertebrate interactions“

Dr. Rebecca Schulte

Host-parasite coevolution is thought to have fundamental consequences for the evolution of organisms. While intensively studied in theory, experimental work is scarce. However, most studies focus on the interaction of parasite and host ignoring that within a host, different parasite genotypes may also interact. Theory and empirical work delivers ambiguous results, revealing either competition between genotypes for limited host resources or cooperation to more efficiently exploit the host. This project employs the model system Caenorhabditis elegans and its microparasite Bacillus thuringiensis allowing a broad screen of multiple parasite genotype interactions and their interaction with diverse host genotypes. As a second step, experimental evolution is applied to elucidate the interaction between parasite genotypes within hosts and the interaction of parasites and hosts over a longer time period, allowing host evolution. Both experimental parts allow extensive phenotypic and genotypic screening of pathogen interactions, bacterial virulence, and host resistance, life-history tradeoffs and the generation and maintenance of diversity and will thus complement other projects of the “Bacillus-Invertebrate Cluster”.