Zero-mode waveguides visualize the first steps during gelsolin-mediated actin filament formation.

ABSTRACT: Actin filament dynamics underlie key cellular processes. Although the elongation of actin filaments has been extensively studied, the mechanism of nucleation remains unclear. The micromolar concentrations needed for filament formation have prevented direct observation of nucleation dynamics on the single molecule level. To overcome this limitation, we have used the attoliter excitation volume of zero-mode waveguides to directly monitor the early steps of filament assembly. Immobilizing single gelsolin molecules as a nucleator at the bottom of the zero-mode waveguide, we could visualize the actin filament nucleation process. The process is surprisingly dynamic, and two distinct populations during gelsolin-mediated nucleation are observed. The two populations are defined by the stability of

SUBMITTER: Hoyer M 

PROVIDER: S-EPMC8790234 | biostudies-literature | 2022 Jan

REPOSITORIES: biostudies-literature