Figure 8-3: Molecular basis for bistability of λ circuitry. a) The OR region is repeated from Fig. 2d. b) Occupancy pattern of OR operators at moderate CI levels. CI binds as a dimer, and dimers at OR1 and OR2 make cooperative interactions. Contrary to this cartoon, structural evidence suggests that both subunits of a dimer touch the other dimer; evidence with LexA suggests that the "hinge" region connecting the dimerization and DNA-binding domains is shorter than implied by this cartoon. c) Occupancy patters of OR operators at moderate levels of Cro. (for better image quality, click here for tif image, which may be quite large; may also require screen refreshing plus special software to view; or view larger tif in separate window)

Figure 8-1, Figure 8-2, Figure 8-3, Figure 8-4

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