| Molecular motor is a kind of protein which not only has enzymatic activity but also has activity of motion. They efficiently convert the chemical energy of ATP into mechanical work to harmoniously make unidirectional motion with the ATP molecular hydrolyzing. Myosin VI has attracted the attention of some scholars in different subjects because of its intriguing functions in cell. Myosin VI has been proposed to play several roles in D. melanogaster during spermatogenesis, and asymmetric cell division, including a role in spindle orientation. Otherwise, its motor function is essential for several physiological functions of the mammalian cell, including normal rates of endocytosis, maintenance of Golgi morphology and protein secretion, and so on.It is known that although the neck domain for myosin VI is shorter than myosin V's, the 36nm displacement is nearly the same for the two molecular motors in every periodicity from some experiments. In addition, the motion for myosin VI which is opposite to other motors is also intriguing features. According to the electric dipole model, we analyzed and discussed the two phenomena mentioned above based on Langevin equation, and obtained that: myosin VI could make stepping motion which is 36nm towards the minus end with the electric dipole model, and the relationship between average current and load force is discussed.In order to reasonably understand the coupled relationship between mechanical states and chemical states, we set up a four-state stochastic hopping model, and qualitatively analyzed the properties of steady state for myosin VI based on Master equation. The result which accords with the myosin VI's biological mechanism is that: the drift velocity increases along with ATP concentration, and decreases along with load force. The conclusion is compatible with the Michaelis-Menten equation, and the change of drift velocity and the diffusion coefficient is the result of the interaction between load force and ATP.
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