TRANSPORT EFFICIENCY OF PASSIVE DIFFUSION OF VIRAL CARGOS IN BIOLOGICAL CELLS

Abstract

Using in silico experiments, we isolate the effects of geometry on the efficiency of passive diffusion transport, PS, of viral cargos to the nuclear region. We model the cell as an elliptical 2D structure (eccentricity e) containing a circular nucleus with radii R (semi-minor) and r, respectively. The cargos move in isotropic random walk inside the cell. PS is estimated as the ratio of the number of cargos that reach the nuclear region and of cargos released. We show that PS decreases with the total distance traveled but increases with r/R. Shifting the nuclear position inside circular cells (e = 0) produce probability distribution functions of total distance traveled that shifts to shorter modes as one side becomes closer to the cell membrane. On the contrary, cargos in more elongated cells (e = 0) have preserved PS-values even for longer distances of travel inside the cell. Finally, an optimum r/R exists due to a trade-off between increased efficiency of transport to the nucleus and high cytoplasmic area. This work could contribute in elucidating the reason why some viruses induce asymmetry in their host cells.