A model for bidirectional traffic of cytoskeletal motors

We introduce a stochastic lattice gas model including two particle species and two parallel lanes, one of which comprises exclusion interaction and directed motion while the other shows no exclusion interaction and unbiased diffusion, thus mimicking a microtubule. lament and the surrounding solution. At a high binding affinity to the. lament, jam-like situations dominate the system's behaviour. We approximated the fundamental process of position exchange of two particles. In the case of a many-particle system, we were able to identify one regime in which the system is rather homogeneous with only small accumulations of particles and another regime in which a significant fraction of all particles accumulate in the same cluster. Numerical data indicate that this cluster formation will occur at all densities for large system sizes. Coupling of several. laments leads to an increased cluster formation as compared to the uncoupled system, suggesting that efficient bidirectional transport on one-dimensional filaments relies on long-ranged interactions and track formation.