Relative velocity of sliding of microtubules by the action of Kinesin-5

TL;DR

This paper presents an analytical model for the steady-state relative sliding velocity of microtubules mediated by Kinesin-5 motors, based on their attachment and detachment rates at ATPase sites.

Contribution

It introduces a novel analytical expression linking Kinesin-5's motor head kinetics to microtubule sliding velocity.

Findings

Derived a formula for relative velocity in terms of motor attachment/detachment rates

Analyzed the motion of motor head pairs on microtubules

Coupled motor head dynamics to determine sliding velocity

Abstract

Kinesin-5, also known as Eg5 in vertebrates is a processive motor with 4 heads, which moves on filamentous tracks called microtubules. The basic function of Kinesin-5 is to slide apart two anti-parallel microtubules by simultaneously walking on both the microtubules. We develop an analytical expression for the steady-state relative velocity of this sliding in terms of the rates of attachments and detachments of motor heads with the ATPase sites on the microtubules. We first analyse the motion of one pair of motor heads on one microtubule and then couple it to the motion of the other pair of motor heads of the same motor on the second microtubule to get the relative velocity of sliding.