Stochastic simulation of processive and oscillatory sliding using a two-headed model for axonemal dynein

Computer simulations have been used in an attempt to understand experimental observations of processive and oscillatory sliding by one or a few axonemal dyneins. A simple two-headed model has been examined using stochastic simulation methods. To explain the experimental observations, the model must be capable of taking backward steps, as well as forward steps, and there must be hysteresis in switching between forward or backward stepping. When the effects of Brownian movement on motor strain are included, it is not possible to obtain oscillations as regular as the experimental records by using motor strain to regulate switching between forward or backward stepping.