The dynamics of the myosin molecular motor as it binds to actin filaments during muscle contraction are still not clearly understood.In this paper,we focus on the coupling mechanism of multi-force interactions in the ...The dynamics of the myosin molecular motor as it binds to actin filaments during muscle contraction are still not clearly understood.In this paper,we focus on the coupling mechanism of multi-force interactions in the myosin molecule during its interaction with actin.These forces include the electrostatic force,the van der Waals force and the Casimir force in molecular dynamic simulations of the molecules in solvent with thermal fluctuations.Based on the Hamaker approach,van der Waals and Casimir potentials and forces are calculated between myosin and actin.We have developed a Monte Carlo method to simulate the dynamic activity of the molecular motor.We have shown that because of the retardation effect,the van der Waals force falls into the Casimir force when the distance between the surfaces is larger than 3 nm.When the distance is smaller than 3 nm,the electrostatic force and the van der Waals force increase until the myosin becomes attached to the actin.Over the distances studied in the present work,the electrostatic force dominates the attractive interactions.Our calculations are in good agreement with recently reported experimental results.展开更多
基金supported by the National Natural Science Foundation of China (60643002,61075101)the Research Fund of State Key Laboratory of MSV, China (MSV-2010-01)+2 种基金the National High-Tech Research and Development Program of China (2006AA04Z240)the Shanghai Dawn Program (07SG14)the Medical and Technology Intercrossing Research Foundation of Shanghai Jiao Tong University (YG2010ZD101)
文摘The dynamics of the myosin molecular motor as it binds to actin filaments during muscle contraction are still not clearly understood.In this paper,we focus on the coupling mechanism of multi-force interactions in the myosin molecule during its interaction with actin.These forces include the electrostatic force,the van der Waals force and the Casimir force in molecular dynamic simulations of the molecules in solvent with thermal fluctuations.Based on the Hamaker approach,van der Waals and Casimir potentials and forces are calculated between myosin and actin.We have developed a Monte Carlo method to simulate the dynamic activity of the molecular motor.We have shown that because of the retardation effect,the van der Waals force falls into the Casimir force when the distance between the surfaces is larger than 3 nm.When the distance is smaller than 3 nm,the electrostatic force and the van der Waals force increase until the myosin becomes attached to the actin.Over the distances studied in the present work,the electrostatic force dominates the attractive interactions.Our calculations are in good agreement with recently reported experimental results.
