Fig. 5

DNAse I footprinting analysis of the Col1a1 promoter using nuclear extracts from prostaglandin-treated BALBc/3T3 fibroblasts.The EcoR1-HindIII fragment of plasmid pG60 was labeled at the EcoR1-5′ end. Lane 1 shows the G + A sequencing reaction of the unlabeled fragment. The end-labeled fragment was incubated without (lane 2, naked DNA) or with nuclear extracts from BALBc/3T3 cells cultured alone (lane 3) or with 250 nM PGE1 (lane 4), PGE₂ (lane 5), or PGF₂^α (lane 6), and treated with DNase I. The different areas of protection by known nuclear factors, as described previously (33,68), are marked by brackets. The numbers at the right correspond to base pairs relative to the start of transcription.