Tropomodulin prevents actin filament growth by:
Pointed end regulation ensures uniform thin filament length in sarcomeres and stability of short filaments in erythrocyte cytoskeleton. Tropomodulin Tmod family capping proteins bind with nanomolar affinity to pointed minus end, preventing subunit addition and dissociation. Domain structure includes two tropomyosin binding amphipathic helices at N terminus residues 1 to 135 that interact with N terminus of tropomyosin coating filament, and C terminal leucine rich repeat domain residues 160 to 359 forming horseshoe that caps terminal actin subunits contacting subdomain 1 and 3 interface. By cla
Ref: Alberts et al., Molecular Biology of the Cell, 7th ed., Chapter 16: Tropomodulin and Pointed End Capping.
