Regulatory RNAs derived from transfer RNA?

Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts 01605, USA.
RNA (Impact Factor: 4.94). 10/2010; 16(10):1865-9. DOI: 10.1261/rna.2266510
Source: PubMed


Four recent studies suggest that cleavages of transfer RNAs generate products with microRNA-like features, with some evidence of function. If their regulatory functions were to be confirmed, these newly revealed RNAs would add to the expanding repertoire of small noncoding RNAs and would also provide new perspectives on the coevolution of transfer RNA and messenger RNA.

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    • "Our deep sequencing studies of serum/plasma have consistently detected tRNA-derived RNAs of size 30–33 nt (Dhahbi et al., 2013a,b). Intracellular tRNA-derived small RNAs are classified into two types based on their size (Sobala & Hutvagner, 2011; Martens-Uzunova et al., 2013): tRNA halves with size of 30–40 nt produced by cleavage of mature tRNAs, and shorter tRNA-derived fragments (tRFs) of size 18–22 nt produced from both mature and pre-tRNAs by Dicer or RNase Z (Thompson et al., 2008; Cole et al., 2009; Fu et al., 2009; Lee et al., 2009; Thompson & Parker, 2009a; Pederson, 2010; Sobala & Hutvagner, 2011). The tRNA halves class includes 5 0 -and 3 0 -tRNA halves that were first observed in stressed cultured cells where they are produced by cleavage of tRNAs near or at the anticodon loop with the ribonuclease Rny1 in Saccharomyces cerevisiae (Thompson & Parker, 2009b) and Angiogenin in higher eukaryotes (Fu et al., 2009; Yamasaki et al., 2009). "
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    • "tRNAs are known to be versatile by playing various roles in gene regulation besides their main function in the translational machinery (Pederson, 2010; Sobala and Hutvagner, 2011). In this section, we will discuss Argonaute-dependent tRNA-fragments (tRFs) that are processed by Dicer-independent mechanisms or generated from precursors with no duplex structures. "
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    • "Interestingly, as yet another " unconventional " small RNA with regulatory functions [61] we also found piRNAs and endo-siRNAs generated from rRNA cleavage. This rRNAderived group was particularly abundant in spermatozoa. "
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