Figure 2 - full size

 

Figure 2.
Fig. 2. Stereo view of the superposition of FK and TPR domains. (a) Two FKBP domains of FKBP51 and FKBP52 were superimposed onto FKBP12. FKBP12 (green), 51-FK1 (blue), and 52-FK1 (red) are similar. The structures of 51-FK2 (cyan) and 52-FK2 (yellow) are more closed than the others. (b) TPR domains are superimposed onto the TPR domains of FKBP52. FKBP52 is shown in yellow, FKBP51 is shown in cyan, Hop is shown in green, Cyp40 is shown in purple, and PP5 is shown in pink. The conformations of all the TPR domains are similar, containing six -helices ( 1- 6). The orientations of the extra -helix ( 7) are different. (c) Superposition of the structures of TPR domains and the 7-helixes of FKBP51 (blue) and FKBP52 (yellow). Gln-333, Phe-335, and Ala-365 of FKBP52 are replaced by Arg-331, Tyr-333, and Leu-363 in FKBP51, which may be responsible for the differential binding pattern of FKBPs to Hsp90. The side chain of Ile-400 of FKBP52, corresponding to Ala-398 of FKBP51, will clash with Phe-369, and this may cause the different orientations of the 7-helix.