Statistical investigations of protein residue direct couplings
Fig 5
Residues in Ran involved in interacting pairs within the transition state structure (pdb: 1k5g) [37].
Sidechains of residues in RanBP1 contacting Ran are labeled in (A) and shown in magenta with dot clouds. The sidechain of Ran Lys130, which plays a role in the stimulation of GTP hydrolysis by RanGAP [37], is indicated. The GTP transition state analog and sidechains of Ran’s catalytic (active site) residues are represented as cyan and red sticks, respectively. A PyMOL session file corresponding to this figure is available at our website. A. Sidechains of residue pairs contributing to the higher S for Ran in the transition state than in the ground state (pdb: 1k5d). These residues are represented as yellow spheres, except for the pivot point residues Phe90 and Val14, which are shown as bright blue spheres, and for two of the unlabeled catalytic residues shown in red (Thr24 and Thr42). B. Ran residues forming pairs whose interactions remain stable over diverse conformational forms (shown as orange and bright blue spheres). These diverse forms include the Ran-RanBP1-RanGAP transition (pdb: 1k5g) and ground (pdb: 1k5d) states; Ran bound to its exchange factor, RCC1 (pdb: 1i2m); Ran bound to GDP (pdb: 3gj0); Ran bound to Ntf1 and GDP (pdb: 1a2k); and Ran bound to RanBP1 and CRM1 (pdb: 4hb2).