Review Papepr

Journal of Muscle Research and Cell Motility

, Volume 29, Issue 6, pp 213-219

Open Access This content is freely available online to anyone, anywhere at any time.

Gestalt-binding of tropomyosin to actin filaments

  • Kenneth C. HolmesAffiliated withArbeitsgruppe Biophysik, Max Planck Institut für medizinische Forschung
  • , William LehmanAffiliated withDepartment of Physiology and Biophysics, Boston University School of Medicine Email author 

Abstract

We argue that the overall behavior of tropomyosin on F-actin cannot be easily discerned by examining thin filaments reduced to their smallest interacting units. In isolation, the individual interactions of actin and tropomyosin, by themselves, are too weak to account for the specificity of the system. Instead the association of tropomyosin on actin can only be fully explained after considering the concerted action of the entire acto-tropomyosin system. We propose that the low K a describing tropomyosin:actin interaction, when taken together with the form-fitting complementarity of tropomyosin strands on F-actin and the tendency for tropomyosin to polymerize end-to-end, make possible unique thin filament functions both locally and at higher levels of filament organization.

Keywords

Actin Tropomyosin Gestalt Gestalt-binding Gestaltbindung Coiled-coil Troponin Calcium Muscle