Which protein severs F-actin filaments and generates free ends?
Filament remodeling during migration requires rapid creation of new ends for turnover. Cofilin ADF family accomplishes this through severing. Preferential binding to ADP F actin saturated regions induces over twist, changing crossover length from 36 to 27 nanometer, reducing bending rigidity and generating strain at boundaries between decorated and undecorated segments. Molecular dynamics simulations show increased fragmentation probability at boundaries. In vitro viscometry demonstrates precipitous drop in viscosity upon addition of low nanomolar cofilin, fluorescence microscopy shows exponen
Ref: Lodish et al., Molecular Cell Biology, 9th ed., Chapter 18: Cofilin Severing and Free Ends Generation.
