SUMO is highly enriched at promoters of actively transcribed genes. (A) Clustering comparison of SUMO1, SUMO2, Pol II, and RNA-seq reads on TSS. (B) Expression status of SUMO-bound TSS (expression defined by a minimum of two RPKM in three mRNA-seq replicates). (C) Merged profiles of SUMO1, SUMO2, Pol II, and H3K4me3 read density with respect to distance from active TSS. (D) Mean profile of SUMO1, SUMO2, and Pol II read density with respect to distance from TSS of genes showing low, middle, and high levels of expression. (E) Venn diagram representing overlap between SUMO1- and SUMO2-marked TSS. (F) Functional annotation of TSS commonly occupied by SUMO1 and SUMO2 using GREAT. The top overrepresented categories belonging to three different ontologies are shown. (G) Scatterplot comparison of common SUMO1- and SUMO2-marked TSS. In red, TSS with a SUMO1/SUMO2 read ratio ≤0.5 or ≥2. (H) IPA upstream regulator analysis of SUMO1-enriched TSS (≥ twofold). (I) Same as in H but for SUMO2.
