Figure 7.

Coupling A-Tailing and RNase R digestion in LiCl-containing buffer enables more efficient enrichment of circular RNAs. (Left) When total RNA is treated with RNase R in KCl-containing buffer, many transcripts with G-quadruplex structures (denoted in pink) or structured 3′ ends (denoted in green) fail to be fully degraded. (Right) Upon inclusion of an A-Tailing step followed by RNase R digestion in LiCl-containing buffer, both of these classes of linear RNAs are more efficiently degraded. This results in isolation of a more pure population of circular RNAs.