Fig. 7.

Experimental results from Yildiz et al. (2008). At left, run length and speed from single molecule assays of kinesins engineered with extended neck linker domains. At right, step size distributions, measured by monitoring the position of a quantum dot attached to one head domain. With this geometry, a normal 8-nm step taken by the motor corresponds to a 16-nm displacement of the labeled head domain (steps in which the unlabeled head takes a step correspond to zero displacement and are not recorded). 6P to 26P correspond to the number of proline residues inserted into the neck linker domain (in addition to two lysines and one glycine), and 14GS denotes a 14 amino acid insert containing glycine and serine residues. Permission for figure pending from Cell Press (Dec, 2010)