Stress-induced breakup: tRNA-derived small RNAs in biology.

The cleavage of full-length transfer RNAs generates functional small RNAs called tRNA-derived small RNAs (tsRNAs or tDRs). This review synthesizes recent advances in our understanding of tDRs, summarizing the molecular mechanisms of their biogenesis and illuminating their function in modulating pathways important in the cellular stress response. Key structural motifs appear to be critical determinants of tDR function by modulating binding to partner proteins and RNAs. Finally, the role of tDRs in the pathogenesis of various diseases and the feasibility of targeting them with novel molecular tools are discussed. In summary, tDRs are an evolutionarily conserved class of small RNAs important for the cellular response to stress and are emerging as a promising target for human diseases.