Supplementary Figure 6: Comparison of DART-Seq to antibody-based m⁶A mapping.

(a) Frequency plot showing the distribution of DART-Seq C to U editing events relative to CIMS and CITS sites at cytidines adjacent to m⁶A from miCLIP data⁵ (left; ‘DART-Seq’). Each individual CIMS or CITS site from miCLIP was centered at 0, and the distance to the nearest C to U editing event from DART-Seq was identified and plotted according to its distance up/downstream of the miCLIP site. For comparison, the same distribution plot was generated using CIMS and CITS sites from a second independent miCLIP study⁶ (right; ‘m⁶A IP’). Both plots demonstrate that C to U editing sites (DART-Seq) or CIMS/CITS sites (m⁶A IP) are frequently enriched at the exact same cytidine that is marked by miCLIP. (b) Frequency plots as in (a) showing the distance of DART-Seq (left) or m⁶A-CLIP (right) sites within 20 nucleotides up/downstream of miCLIP CIMS/CITS sites. (c) Identity and frequency of the nucleotide immediately preceding C to U mutation sites in DART-Seq datasets from cells expressing APOBEC1-YTH or APOBEC1 alone. There is a strong preference for A residues preceding C to U editing sites in APOBEC1-YTH-expressing cells (n = 40,263 APOBEC1-YTH; n = 8,774 APOBEC1).