Coarse-grained simulations of actin polymerization

The polymerization of actin, which plays a central role in maintaining cell structure and motility, is regulated by multiple monomer and filament binding proteins containing flexible disordered regions. Computational studies of actin polymerization require the use of coarse-grained models, since the timescales to simulate polymerization kinetics using all-atom models are too long. We show the promise of previously developed coarse-grained models with each residue represented by a single interaction site. We used such models to reproduce the polymerization of actin monomers to the barbed and pointed ends of actin filaments, the binding of profilin to actin, and the delivery of profilin-actin to the barbed end through flexible disordered regions of actin filament regulators.