Is Actin the Thin Filament

Thin filaments are composed primarily of the contractile protein actin. As illustrated in Figures 2-8, A and B, actin is composed of small globular subunits (G actin) that form long strands called fibrous actin (F actin).

Is actin an elastic filament?

Cross-linking proteins bind the actin filaments together to form elastic gels or bundle structures, such as in stress fibers and filopodia. … F-actin is a semiflexible polymer; the persistence length is 17 μm (10).

What are the types of actin?

actin, protein that is an important contributor to the contractile property of muscle and other cells. It exists in two forms: G-actin (monomeric globular actin) and F-actin (polymeric fibrous actin), the form involved in muscle contraction.