Intracellular Transport is Sensitive to Filament Polarization

In eukaryotic cells, the intracellular transport process involves the movement of materials such as proteins, lipids, carbohydrates, and nucleic acids via phases of passive, diffusive transport and active, motor-driven transport in which molecular motors carry cargos in relatively straight lines along filaments that make up the cell’s cytoskeleton. We have developed a numerical technique to model this process where distributions of cargos are evolved in time. The distributions move via advection along filaments when designated as being on filaments and diffusion when considered off filaments. With our results, we compare first-passage times to those achieved through simulations of individual cargo movement and analyze the effects of filament lengths and polarizations on the distribution’s survival probability at given points in time. We find that for some network parameters, particularly for intermediate filament length values, cargos become more easily trapped throughout the cell which leads to relatively high survival probabilities.