Repurposing tRNA isodecoders for non-canonical functions via tRNA cleavage.

Unlabelled: Transfer RNAs (tRNAs) are the key adaptor molecules aiding protein synthesis. Hundreds of tRNA genes are found in the human genome but the biological significance of this genetic excess is still enigmatic. The tRNA repertoires are variable between tissues and cells as well as during development.

RTCB Complex Regulates Stress-Induced tRNA Cleavage.

Under stress conditions, transfer RNAs (tRNAs) are cleaved by stress-responsive RNases such as angiogenin, generating tRNA-derived RNAs called tiRNAs. As tiRNAs contribute to cytoprotection through inhibition of translation and prevention of apoptosis, the regulation of tiRNA production is critical for cellular stress response. Here, we show that RTCB ligase complex (RTCB-LC), an RNA ligase complex involved in endoplasmic reticulum (ER) stress response and precursor tRNA splicing, negatively regulates stress-induced tiRNA production.