E- Differential mRNA isoform usage upon CTD shortening. Scatter plot showing read counts for mRNA isoforms detected in the chromatin fraction of RPB1-52R and RPB1-25R cells using long read sequencing. 47416 isoforms were detected, RPB1-52R condition was used as a control. 335 isoforms show differential expression (p value < 0.05, Fischer's exact test). 