Schaefer, M., Pollex, T., Hanna, K., Tuorto, F., Meusburger, M., Helm, M., Lyko, F. (2010). RNA methylation by Dnmt2 protects transfer RNAs against stress-induced cleavage. Genes Dev. 24(15): 1590--1595.
FlyBase ID
FBrf0211424
Publication Type
Research paper
Abstract
Dnmt2 proteins are the most conserved members of the DNA methyltransferase enzyme family, but their substrate specificity and biological functions have been a subject of controversy. We show here that, in addition to tRNA(Asp-GTC), tRNA(Val-AAC) and tRNA(Gly-GCC) are also methylated by Dnmt2. Drosophila Dnmt2 mutants showed reduced viability under stress conditions, and Dnmt2 relocalized to stress granules following heat shock. Strikingly, stress-induced cleavage of tRNAs was Dnmt2-dependent, and Dnmt2-mediated methylation protected tRNAs against ribonuclease cleavage. These results uncover a novel biological function of Dnmt2-mediated tRNA methylation, and suggest a role for Dnmt2 enzymes during the biogenesis of tRNA-derived small RNAs.
