Genes with 3'-biased PolII occupancy are preferentially activated during stress response. (a, b) PolII occupancy at the 5' CDS, mid-CDS, and 3' CDS was calculated before (t = 0) and after (t = 30) heat shock for genes repressed (a), or activated (b) at least two-fold  during heat shock. (c) Genes are ordered by the level of induction after 30 minutes of heat shock. On the y-axis are plotted 80-gene running windows for change in PolII occupancy over mid-CDS, and for the 5'/3' PolII occupancy ratio at t = 0. DPol2 indicates change in PolII; Pol2, RNA polymerase II.