The world of small noncoding RNAs (sncRNAs) is ever-expanding, from small interfering RNA, microRNA and Piwi-interacting RNA to the recently emerging non-canonical sncRNAs derived from longer structured RNAs (for example, transfer, ribosomal, Y, small nucleolar, small nuclear and vault RNAs), showing distinct biogenesis and functional principles. Here we discuss recent tools for sncRNA identification, caveats in sncRNA expression analysis and emerging methods for direct sequencing of sncRNAs and systematic mapping of RNA modifications that are integral to their function.
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We thank P. Schimmel (The Scripps Research Institute), X. Chen (UC Riverside) and our laboratory members for critical discussions on the contents of the manuscript. Research in the Q.C. laboratory is in part supported by the National Institutes of Health (NIH grant nos R01HD092431, R01ES032024 and P50HD098593). The T.Z. laboratory is in part supported by the NIH (grant no. R01ES032024).
The authors declare no competing interests.
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Shi, J., Zhou, T. & Chen, Q. Exploring the expanding universe of small RNAs. Nat Cell Biol 24, 415–423 (2022). https://doi.org/10.1038/s41556-022-00880-5
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