Figure 4.
Intronic miRNAs with independent intronic transcription initiation regions. (A) Intronic miRNAs with independent intronic transcription initiation regions are located significantly farther (median distance 57 kb) from host TSSs than those that share the host TSSs. miRNA TSSs are indicated by arrows. (B) Box plots of distance between host TSS and mature miRNA for intronic miRNAs with and without independent transcription initiation regions. There was a significant difference in the two distributions (P-value = 5.1 × 10−7), indicating that intronic miRNAs that have acquired independent promoters for faster transcription are likely located far from host gene TSSs.