Actin Filament Growth Stages

Actin filament growth starts when G-actin, or monomeric actin, links together to form F-actin, the filament form. This process builds the actin network in cells through head-to-tail binding between actin subunits. It moves through three stages: nucleation, elongation, and the steady-state phase.

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Actin polymerization can occur spontaneously or through actin-binding proteins.

Spontaneous actin polymerization has three phases: nucleation, elongation, and steady-state.

During nucleation, three actin monomers assemble into an actin nucleus.

In elongation, monomers are rapidly added to either end of the nucleus forming a ...