High-throughput sequencing of small RNAs (25-70 nt) from Drosophila wild-type and Dnmt2 mutants

Dnmt2 genes are highly conserved tRNA methyltransferases with biological roles in cellular stress responses. The absence of obvious mutant phenotypes under laboratory conditions suggested a function for Dnmt2 under non-physiological conditions. Indeed, Dnmt2 has recently been implicated in various aspects of the cellular stress response and the tRNA methyltransferase activity of Dnmt2 has been shown to interfere with stress-induced fragmentation of various tRNAs. We used adult animals and small RNA sequencing during a heat stress experiment to determine the tRNA fragment abundance and identities in wild-type and Dnmt2 mutant somatic tissues. Dnmt2 mutants produced tRNA fragments with different identities when compared to wild-type controls, indicating the accumulation of non-physiological tRNA-derived molecules in tissues without Dnmt2. Overall design: 6 samples examined: heterozygous and Dnmt2 mutant under control, heat shock and recovery conditions