Fig. 3
From: Multilayered control of exon acquisition permits the emergence of novel forms of regulatory control
Reduced rate of RNA polymerase II elongation and poor splicing efficiency promotes exonization. a Dot plot showing the impact of RNA polymerase mutations on exonization of Alu-containing exons. WT, wildtype; Fast, E1126G mutation; Slow, R749H mutation. Each point represents individual dataset. KB, kilobase; min, minutes. Elongation, rate of transcriptional elongation (see the “Methods” section and [24]). b Boxplot of splicing efficiency for introns with exonization events vs all expressed introns with no evidence of exonization. Splicing efficiency is a metric describing speed of intron excision as measured by assessing nascent RNA-seq using BrU-chase at 0, 15, 30, and 60 min. See Fig. 2d for the description of boxplots. ***p < 1 × 10−10 p value calculated using Wilcoxon-rank sum test. (n = 4,011). c Stacked bar plot showing distributions of introns for splicing efficiency identified by BrU-chase. Groups assigned by K-means clustering (k = 5) (see the “Methods” section)—see Additional file 1: Figure S3a for distributions of splicing efficiencies. (n = 83,972)