Figure 2: Changes in tubulin-bound apo-kinesin on ATP binding.
From: The structure of apo-kinesin bound to tubulin links the nucleotide cycle to movement
(a) The three subdomains whose movements account for structural changes during the nucleotide cycle. For clarity, the strands that are not part of the central β sheet are not labelled. The subdomains connecting loops are in grey. (b) The movement of the Switch I/II subdomain on ATP binding. In this and in c, the tubulin-binding blocks in ATP-like and in apo-kinesin have been superimposed and the subdomain that is not being compared is shown as a semi-transparent model. (c) The movement of the P-loop subdomain; for clarity, strands β1a–β1c, which are not part of the central β sheet, have been omitted. (d) The effect of the P-loop subdomain rotation on neck-linker docking. P-loop subdomains in ATP-like and apo-kinesin are presented following superposition of the tubulin-binding blocks. The location of the first neck-linker residue (Ile325) in ATP-like kinesin is occupied by Ile9 in nucleotide-free kinesin (the atoms linked by a black solid line are 1.2 Å away). As a consequence, in the nucleotide-free complex the kinesin polypeptide chain is disordered after Lys323.
