FIGURE 3 

Repression is effective at all three positions, following the trend coreproximaldistal. Measurements of repressed single-input promoters. Responses are colored according to the repressor: LacI (filled) or TetR (open). Each promoter contains a single operator located at distal (A), core (B), or proximal (C) positions. Single-input activities are plotted in the induced (unregulated) versus uninduced (repressed) states. In some promoters, operators do not effectively repress the promoter (points located near solid black line). Luciferase detection limits are shown with gray dashed lines.