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Updated: Jun 25, 2026

Probing Myosin Ensemble Mechanics in Actin Filament Bundles Using Optical Tweezers
Published on: May 4, 2022
Tropomyosin: function follows structure
1Department of Neuroscience and Cell Biology, Robert Wood Johnson Medical School, 675 Hoes Lane, Piscataway, New Jersey 08854, USA. hitchcoc@umdnj.edu
Abstract:
Tropomyosin is known as the archetypal coiled coil, being the first to be sequenced and modeled. Studies of the structure and dynamics of tropomyosin, accompanied by biochemical and biophysical analyses of tropomyosin, mutants and model peptides, have revealed the complexity and subtleties required for tropomyosin function. Interruptions in the canonical coiled coil allow for bends and regions of local instability that are required for tropomyosin to bind to the helical actin filament. This chapter highlights insights gained from recent structural studies as they relate to variations in tropomyosin's coiled-coil structure that are essential for binding to actin and the relationship of periodic repeats to actin molecules in the filament.
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