Three-Dimensional Model of Cooperative Transport of Pairs of Kinesin-1 and −2 Motors

Abstract

Motor proteins are fundamentally important as they are involved in many intercellular activities such as cell division, neurotransmission, and muscle contraction. Due to experimental challenges, the mechanisms of many kinesin family motors remain unclear during multimotor transport. In the past decade, computer simulations have become an important tool in characterizing such cooperative transport by families of kinesin motors, particularly in conjunction with distinct number of motors attached to a DNA scaffold. Here, we present Langevin dynamics simulations and that capture kinesin-1/kinesin-2 motor mechano-chemistry in a three-dimensional scaffold geometry, and show how both motor's distinct force sensitivities to detachment play an important role in multi-motor transport. In particular, our model is able to recapitulate not only the observed velocities of the 2-motor complexes but also the experimentally measured run lengths. Our results also suggest that the variance of the end-to-end reattachment is another key parameter in multi-motor transport besides critical detachment force and reattachment rate.