Actin is essential for the survival and pathogenicity of the Apicomplexan parasite Toxoplasma gondii, where it plays essential functions in cargo transport, invasion, egress, and organelle inheritance. Recent work has shown that, unlike vertebrate skeletal muscle actin, purified T. gondii actin filaments (TgAct1) can undergo rapid treadmilling, due to large differences in the barbed- and pointed-end critical concentrations, rapid subunit dissociation from filament ends, and a rapid nucleotide exchange rate constant from free monomers.
