Fig. 4. Examples of RNA secondary structure changes of NEIL1 variants.

a Compensatory mutation generally maintains a high editing level. Editing site is highlighted in blue. The dashed circle marks the location of compensatory double mutation. The b editing level and c similarity score (normalized score calculating the similarity of the MFE structure of each variant to the WT) vary by different mutation types. Single mutation (blue dot); double-transversion mutation (yellow dot); compensatory mutation (gray dot). The data points shown are the average editing level from six biological replicates. Boxplot: center line, median; box limits, upper and lower quantiles; whiskers, ±1.5× interquartile range (IQR). The P values from two-sided Wilcoxon rank-sum test are shown on each test set. d Alterations in the 5′ stem and 3′ non-stem structure elements affect editing level. Editing site is highlighted in blue and mutation region shown as dashed circle (deletion of stem from the 5′ stem), orange highlight (insertion of stem), or red highlight (mutation, deletion, or insertion of nucleotides of the 3′ internal loop).