Fig. 9. Computer modeling of the structure of model peptides (A,C) and importin-ß (B,D) with Pro (A,B) and Leu (C,D) in the linker region between HEAT repeats 10 and 11. In computing the structure of the peptides and the proteins only three angles were changed as shown on the figure. Leu439 and Leu440 are Ile444 and Ile445 in Drosophila. Pro, Leu and Ser in the critical position appear dark blue, light blue and yellow, respectively.