Force Generated by Actin Array

We study a theoretical model for a group of parallel filaments growing against a barrier held by a constant force. An array of N filaments nucleate on a fixed surface and grow towards a rigid barrier which is held in place by a constant force. Filaments are coupled only by mechanical contact against the barrier. We obtain the filament density distribution in terms of the distance from the barrier, and force-velocity curves. We apply our model to the case of an array of actin filaments. All results are validated by extensive Monte-Carlo simulations. For a small value of N we find the stall force to be N times the stall force of a single filament ($f_{stall}\approx Nf_{stall}^1$). For large N we find that the velocity \textit{appears} to be considerably smaller, an effect due to its exponential decrease as the theoretical stall force is approached.