Actin serves as one of the major cytoskeleton structures. It is a crucial component involved in a plethora of processes in cell biology: stabilizing the cell shape, cell movements (e.g. cell migration) and intracellular movements and transport mechanisms.
Actin is a 43 kDa protein that is very highly conserved between species. Actin has three main isotypes (α-actin, β-actin and γ-actin), which show >90% amino-acid (aa) homology between isotypes and >98% homology within members of a particular isotypic group.