Figure 3.

Recognition of NU2058 by GR. (A) Hydrogen bonding interactions between NU2058 and GR. The binding pocket of the guanine-GR complex is superimposed, emphasizing the shift of C74 towards the minor groove, resulting in two hydrogen bonds between the ligand and RNA. (B) Binding pocket of the NU2058-GR complex with density from a simulated annealing composite map contoured at 1 around the ligand and nucleotides U51 and C74. Only two atoms in the methylcyclohexyl group have a clear density, indicating that this moiety of the ligand is highly conformationally flexible.