EDEN-BP dimerises in a yeast two-hybrid assay. HF7c cells that had been transformed by pGBT9/EDEN-BP (DNA-binding domain/EDEN-BP fusion protein) were subsequently transformed with either pAD/EDEN-BP (activating domain/EDEN-BP fusion protein) or pAD/IRP (activating domain/iron regulatory fusion protein) as indicated at the top of the figure. Serial dilutions (1/10) of individual clones were replica plated on the indicated medium (–LW, medium lacking leucine and tryptophan; –HLW, medium lacking histidine, leucine and tryptophan). When used, the concentration of 3-AT was as indicated (5, 10 and 20 mM).