The cyclic peptide phalloidin binds and stabilizes actin filaments. It is widely used in studies of actin filament assembly, including analysis of branch formation by Arp2/3 complex, but its influence on the branching reaction has not been considered.

How is actin stabilized?

Binding of cofilin to F-actin is inhibited by D-loop rearrangement. The rearrangement of the D-loop from monomer 3 explains the tighter binding between the actin monomers 2 and 3 as MiuA stabilizes these inter-strand contacts.

How are actin filaments stabilized?

Actin Filaments in Solution also Stabilize with Age. ... Polymerization of 3 μM actin was initiated by salt addition. Actin was polymerized for different times and then allowed to depolymerize by addition of a stoichiometric excess of a monomer trap.