FAQ: What are circular RNAs?

Circular RNAs are single-stranded RNAs that form a covalently closed loop. These RNAs are resistant to exoribonucleases, such as RNase R (NEB #M0100), because there is no free end for these exoribonucleases to bind to. This resistance to exoribonucleases makes circular RNAs more stable than their linear counterparts.