Figure 1.

Irradiation with UVC light preferentially inhibits elongation with little effects on initiation of transcription. (A) Aggregate graph showing a UV dose-dependent reduction of reads in the bodies of genes and an enhancement of reads at the 5′-end of 988 genes longer than 20 kbp. Human fibroblasts were irradiated with UVC light and incubated with Bru for 30 min to label the nascent RNA and the nascent transcription reads are aligned from their transcription start site (TSS). (B) UV-mediated reduction in RNA synthesis is proportional to gene size. Ratio of Bru-seq signal (RPKM) of individual genes in UV-irradiated over control cells as a function of gene size. (C) The median length of genes showing relative induction or inhibition at least 2-fold directly after UV-irradiation (30 min Bru-labeling) or (D) following a 6-h recovery period. The gene maps are from RefSeq gene annotation (UCSC genome browser).