Fig. 2.

Estrogen pretreatment results in increased PR occupancy on DNA. a Steady state levels by immunoblotting of ERα, PR-A and PR-B in response to 4 h of 10nM progesterone treatment alone or 72 h 10nM estrogen treatment followed by 4 h 10nM progesterone treatment. b Conservation in the 475 progesterone alone PR binding sites versus the 4597 estrogen pretreated, progesterone PR binding sites in ZR-75-1 cells. c Relative strength of progesterone alone and estrogen pretreated, progesterone PR binding sites using peak annotation in HOMER. d The number of reads per peak are centred around the middle of the binding sites in both data sets. e De novo analysis of the estrogenpprogesterone PR dataset using both GIBBS and MEME revealed a PRE-like sequence as the most highly enriched motif. No PRE-like motif was found on de novo analysis of the progesterone alone dataset. (f) Distribution of the binding sites relative to the nearest TSS reveal a similar distribution to that of other studies [27, 29] and other receptors [31, 55]. g Binding sites were significantly enriched around the TSS of genes