Transposable element targeting by piRNAs in Laurasiatherians with distinct TE activities

Transposable elements (TEs) are self-mobilizing elements that make up a large fraction of mammalian genomes. PIWI proteins and PIWI interacting RNAs (piRNAs) are a part of a system aimed at controlling and preventing TE proliferation. We examined the TE landscape and piRNA repertoires from three non-model Laurasiatherian mammals (dog, horse and big brown bat) with differing TE complements and proliferation patterns to address questions about the evolutionary relationships between piRNAs and TEs. We found that the genomic abundance of new TEs may not match TE transcription. We speculate that a higher rate of SINE targeting by piRNAs in the horse genome contributed to the reduced SINE insertion rate. Overall design: Two testicular tissue sample from three taxa. Six samples total