Position-Induced Phase Change in a TASEP with a Double-Chain Section (a Model of Biological Transport)

Abstract

The totally asymmetric simple exclusion processes (TASEP) has beenused since 1968 to model different biochemical processes,including kinetics of protein synthesis, molecular motors traffic,collective effects in genetic transcription. Here, we considerTASEP defined on an open network consisting of simple head andtail chains with a double-chain section in-between. Our results of Monte Carlo simulations show a novel property of the model when the simple chains are in the maximum-current phase: upon moving the double-chain defect from the central position forward or backward along the network, keeping fixed the length of both the defect and the whole network, a position-induced phase change in the parallel defect chains takes place. This phenomenon is explained in terms of finite-size dependence of the effective injection and removal rates at the ends of the double-chain defect. Some implications of the results for molecular motors cellular transport along such networks are suggested. However, at present these are just speculations which need further examinations.

Keywords

• TASEP
• Molecular motors traffic
• kinetics of protein synthesis
• traffic flow models
• non-equilibrium phase transitions
• non-equilibrium statistical physic