Genome-wide occupancy of FLAG-ERG and FLAG-EHF in RWPE1 cells

We compared the genome occupancy for FLAG-tagged versions of the ETS factors ERG and EHF in the normal prostate epithelial cell line RWPE1. Our in vitro binding studies support a model whereby oncogenic ETS factors like ERG bind cooperativly with AP1 factors at closly spaced ETS-AP1 sites, while certain non-oncogenic factors like EHF bind anti-cooperatively with AP1 at the same sites. ETS and AP1 binding motifs were enriched in both ChIP datasets, but the ERG-FLAG bound reginos contained a much higher percentage of ETS-AP1 sites spaced in close proximity, consistent with our in vitro binding data. Overall design: ChIP-seq with anti-FLAG antibody in RWPE1 cells expressing either FLAG-ERG or FLAG-EHF