When driven out of equilibrium by the consumption of biochemical energy, cytoskeletal protein filaments alone and in combination with molecular motors are able to generate sufficient forces to deform and move cells as well as to transport cargo within a cell. I will present some of my group’s theoretical work on force generation mechanisms using both analytical calculations and simulations in combination with experimental data.

First I will discuss our work on polymerising branched actin, comparing in vitro data with simulations and analytical calculations. Then I will present stochastic simulations of polymerising branched actin exerting force to deform a model membrane in the context of phagocytosis, which is a process by which immune cells engulf pathogens.

In the second part of the talk I will present analytical calculations and simulations of molecular motors moving along cytoskeleton filaments transporting a cargo. I will compare our results with experimental data of molecular motors on microtubules in vitro and in vivo. In particular I will discuss the differences between processive and non-processive motors and the effects of multiple motors and multiple filaments. Finally I will discuss the effects of competing molecular motors pulling a cargo in different directions for a deformable cargo.