The role of dynamic defects in transport of interacting molecular motors

Abstract

Motor proteins or biological molecular motors are special enzyme molecules that drive biological transport in living cells by moving cellular cargoes along linear protein filaments. The experimental evidences suggest that while performing their mechanical work biological molecular motors interact with each other, and there are other biological molecules on their tracks that influence their progression. Stimulated by these observations, we propose a onedimensional totally asymmetric simple exclusion process with nearest-neighbor interactions and a dynamic defect that is allowed to reversibly bind and unbind at a specific site far away from the boundaries. A theoretical framework based on cluster mean-field approximation is adopted to determine the stationary properties of the system. The role of interactions and the eect the reversible defect associations on the dynamics of the system is discussed. It is found that three or less stationary phases can exist in the system, depending on the interaction strength, and only one of them is strongly aected by the defect association/dissociation dynamics. The theoretical results are validated through extensive Monte Carlo simulations.