A STOCHASTIC MODEL FOR THE STEPWISE MOTION IN ACTOMYOSIN DYNAMICS

A jump-diffusion process is proposed to describe the displacements performed by single myosin heads along actin filaments during the rising phases. The process consists of the superposition of a Wiener and a jump process, with jumps originated by sequences of Poisson-distributed energysupplying pulses. In a previous paper [6], the amplitude of the jumps was described by a mixture of two Gaussian distributions. To embody the effects of ATP hydrolysis [1], we now refine such a model by assuming that the jumps’ amplitude is described by a mixture of three Gaussian distributions. This model has been inspired by the experimental data of T. Yanagida and his co-workers concerning observations at single molecule processes level as described in [10] and in the references therein.