Blocks the elongation and depolymerization of the actin filaments at the pointed end. The Tmod/TM complex contributes to the formation of the short actin protofilament, which in turn defines the geometry of the membrane skeleton (By similarity). Binds to the N-terminus of tropomyosin and to actin. Binds to TMBr3 as well as to other low molecular mass tropomyosins (TM5a or TM5), but not to high molecular mass tropomyosins (TM2 or TMBr1). Neuronal-tissue specific. Belongs to the tropomodulin family.