Toward an Understanding of Extracellular tRNA Biology

Extracellular RNAs (exRNAs) including abundant full length tRNAs and tRNA fragments (tRFs) have recently garnered attention as a promising source of biomarkers novel mediator in cell-to-cell communication eukaryotes. Depending on the physiological state cells, tRNAs/tRFs are released to extracellular space either contained vesicles (EVs) or free, through mechanism that is largely unknown. In this perspective article, we propose (ex-tRNAs) and/or tRFs (ex-tRFs) relevant paracrine signaling molecules whose activity depends mechanisms release by cells capture recipient cells. We speculate how ex-tRNA/ex-tRFs orchestrate effects target depending type sequence uptake. further modifications may be playing important roles ex-tRNA biology.