Circular RNAs (circRNAs) are formed in all domains of life and via different mechanisms. There has been an explosion in the number of circRNA papers in recent years; however, as a relatively young field, circRNA biology has an urgent need for common experimental standards for isolating, analyzing, expressing and depleting circRNAs. Here we propose a set of guidelines for circRNA studies based on the authors’ experience. This Perspective will specifically address the major class of circRNAs in Eukarya that are generated by a spliceosome-catalyzed back-splicing event. We hope that the implementation of best practice principles for circRNA research will help move the field forward and allow a better functional understanding of this fascinating group of RNAs.
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This work was supported by the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement no. 721890 (circRTrain). A.F.N. and J.K. are funded by the Danish National Research Foundation grant no. 135 (CellPAT). M.T.J.O. is funded by the Danish Cancer society grant R269-A15768. L.S.K. is funded by the Lundbeck Foundation (R307-2018-3433). I.B. acknowledges funding from ERC-2019-SyG 855923-ASTRA and from AIRC-Progetto IG 2019 ID no. 23053. A.B. is funded by the Deutsche Forschungsgemeinschaft via grants RTG 2355, SPP 1935 and RU5116. S.K. acknowledges funding from the National Institute of Health (R01GM124406 and R01AG057700).
The authors declare no competing interests.
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Nielsen, A.F., Bindereif, A., Bozzoni, I. et al. Best practice standards for circular RNA research. Nat Methods (2022). https://doi.org/10.1038/s41592-022-01487-2