Figure 1

Relative entropy analysis of 6,887 canonical-length (34 aa) TPR repeats. (a) The relative entropy values are shown for each TPR position, with secondary structure indicated (cylinders represent helices and lines represent loops). Arrows indicate the positions of the seven most variable residues. These values are mapped onto the co-crystal structures of HOP-TPR1/Hsc70 peptide (b) and HOP-TPR2A/Hsp90 peptide (c), with the TPR domains rendered in spheres and the ligands in sticks. Two views from 180° rotation of each molecule are shown. The concave, ligand binding surfaces, left, are clearly more variable than the convex, solvent exposed surfaces, right. A small insertion in TPR2A is colored grey. (d) Views of the concave binding surfaces as in (c), but only those residues known to contact the ligand from co-crystal structures are colored [19]. Rendered from PDB entries 1ELW and 1ELR using PyMOL.