Figure 4

Comparison of the force-dependence of the velocities of Eg5 and conventional kinesin. Eg5 (red, left axis) [30] and conventional kinesin (blue, right axis) [37] velocity as a function of force, as measured with a force-clamped optical trap. Positive forces indicate that load was applied toward the plus-end of the microtubule, assisting motion; negative forces hinder translocation. Conventional kinesin slows much more dramatically than Eg5 does under hindering load.