Profilin's Affinity for Formin Regulates the Availability of Filament Ends for Actin Monomer Binding.

ABSTRACT: Nucleation-promoting proteins tightly regulate actin polymerization in cells. Whereas many of these proteins bind actin monomers directly, formins use the actin-binding protein profilin to dynamically load actin monomers onto their flexible Formin Homology 1 (FH1) domains. Following binding, FH1 domains deliver profilin-actin complexes to filament ends. To investigate profilin's role as an adaptor protein in formin-mediated elongation, we engineered a chimeric formin that binds actin monomers directly via covalent attachment of profilin to its binding site in the formin. This formin mediates slow filament elongation owing to a high probability of profilin binding at filament ends. Varying the position at which profilin is tethered to the formin alters the elongation rate by modulating prof

SUBMITTER: Zweifel ME 

PROVIDER: S-EPMC7738411 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature