Effect of Kinesin-5 Tail Domain on Motor Dynamics for Antiparallel Microtubule Sliding

Kinesin-5 motor consists of two pairs of heads and tail domains, which are situated at the opposite ends of a common stalk. The two pairs of heads can bind to two antiparallel microtubules (MTs) and move on the two MTs independently towards the plus ends, sliding apart the two MTs, which is responsible for chromosome segregation during mitosis. Prior experimental data showed that the tails of kinesin-5 Eg5 can modulate the dynamics of single motors and are critical for multiple motors to generate high steady forces to slide apart two antiparallel MTs. To understand the molecular mechanism of the tails modulating the ability of Eg5 motors, based on our proposed model the dynamics of the single Eg5 with the tails and that without the tails moving on single MTs is studied analytically and compared. Furthermore, the dynamics of antiparallel MT sliding by multiple Eg5 motors with the tails and that without the tails is studied numerically and compared. Both the analytical results for single motors and the numerical results for multiple motors are consistent with the available experimental data.

Robust fixed time controller with motor dynamics and composite disturbances for a quadrotor unmanned aerial vehicle

A fixed time robust control method is presented for trajectory tracking control of quadrotor systems with motor dynamics in the presence of unmodeled disturbances and external disturbances. The recommended control method avoids the negative effect to the quadrotor system caused by motor dynamic which is considered as first-order dynamic with dynamic disturbance. And fixed time extended state observer is adopted to estimate the composite disturbances and obtain the first and second derivative of desired trajectory and virtual control. Together with fixed time convergence control method, the stability and convergence characteristics of quadrotor system can be guaranteed. Finally, several simulations prove the effectiveness of the novel method with different time constants of motor dynamics.

Tuning molecular motor transport through cytoskeletal filament network organization

Myosin II motor dynamics have signatures that report on the structure of the underlying network of crosslinked cytoskeletal filaments.