Genetic Variation in Host Tolerance of an Invading Transposon in Drosophila melanogaster


Transposable Elements (TEs) are both important drivers of genome evolution and genetic parasites with potentially dramatic consequences for host fitness, including insertional inactivation of functional sequences and genomic instability (Reviewed in Hedges and Deininger 2007). Although host genomes minimize these deleterious eff¬ects by regulating the activity of resident TEs, they are often invaded by new TE families, which they are unable to control (Reviewed in Wallau et al. 2012). We are taking advantage of the historical invasion of the Drosophila melanogaster genome by P-elements (Reviewed in Engels 2003), a family of autonomous DNA transposons, to understand the impact that invading TEs have on their hosts, and the mechanisms through which TE regulation evolves. Using a panel of recombinant inbred lines (RILs), which were generated from naïve genotypes isolated from nature before P-element invasion (King et al. 2012), we have identified genetic variants that allow for tolerance or control of P-element activity. Such variants could have been beneficial after P-elements invaded D. melanogaster genomes ~1950, thereby contributing to the evolution of tolerance of the transposable element by its host.