Structural mapping of GII and PIE RNA. (A) A scatter plot showing the correlation between PIE circularization and GII splicing from different group I intron sequences. (B) Comparison of Gv and Po in SHAPE-MaP correlation between GII and PIE. (C–E) Mapping of intramolecular interactions in Po PIE Gluc and Gv PIE Gluc. Data are presented in arc plots and bar graphs showing interaction types. H1 and H2 indicate homology 1 and homology 2, respectively. Differential analysis was performed using an independent student’s t-test: ∗P< .05. (F) Key interactions in Po PIE Gluc and base-pairing regions from RNAcofold analysis are highlighted in red (I) and green (II). (G, H) Indicated constructs were IVT and their IVT products were analysed by E-gel EX electrophoresis. The green circle indicates circular RNA. The blue line indicates IVT RNA precursor, and the red circle indicates nicked circular RNA. Each experiment was performed two times independently and representative gel images are shown.