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bioRxiv · 10.1101/2020.12.15.422816

The 3'tsRNAs are aminoacylated: Implications for their biogenesis

Liu, Z.·Kim, H. k.·Xu, J.·Kay, M. A.
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Abstract

Emerging evidence indicates that tRNA-derived small RNAs (tsRNAs) are involved in fine-tuning gene expression and become dysregulated in various cancers. We recently showed that the 22nt LeuCAG tsRNA from 3 end of tRNALeu is required for efficient translation of a ribosomal protein mRNA and ribosome biogenesis. Inactivation of this tsRNA induced apoptosis in rapidly dividing cells and suppressed the growth of a patient derived orthotopic hepatocellular carcinoma in mice. The mechanism involved in the generation of the 3-tsRNAs remains elusive and it is unclear if the 3-ends of 3-tsRNAs are aminoacylated. Here we report an enzymatic method utilizing exonuclease T to determine the 3charging status of tRNAs and tsRNAs. Our results showed that the LeuCAG 3-tsRNA is fully charged and originated solely from charged mature tRNA. When the leucyl-tRNA synthetase was knocked down, less tsRNA was generated while the mature tRNA was not reduced further supporting that tsRNA generation is regulated. The fact that the 3-tsRNA is aminoacylated has implications for their biogenesis and provides additional insights into their biological role in post-transcriptional gene regulation.

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Liu, Z., Kim, H. k., Xu, J., Kay, M. A.. 2020-12-16. The 3'tsRNAs are aminoacylated: Implications for their biogenesis. https://doi.org/10.1101/2020.12.15.422816

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