Kinesin Processivity Is Determined by a Kinetic Race from a Vulnerable One-Head-Bound State.

ABSTRACT: Kinesin processivity, defined as the average number of steps that occur per interaction with a microtubule, is an important biophysical determinant of the motor's intracellular capabilities. Despite its fundamental importance to the diversity of tasks that kinesins carry out in cells, no existing quantitative model fully explains how structural differences between kinesins alter kinetic rates in the ATPase cycle to produce functional changes in processivity. Here we use high-resolution single-molecule microscopy to directly observe the stepping behavior of kinesin-1 and -2 family motors with different length neck-linker domains. We characterize a one-head-bound posthydrolysis vulnerable state where a kinetic race occurs between attachment of the tethered head to its next binding site and d

SUBMITTER: Mickolajczyk KJ 

PROVIDER: S-EPMC5479115 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature