The three state model of tropomyosin (Tm), positioning along filamentous actin allows for Tm to act as a gate for myosin head binding with actin. The blocked state of Tm prevents myosin binding while the open state allows for strong binding. Intermediate to this transition is the closed state. The details of the transition from the blocked to the closed state, and then finally to the open state by Tm have not been fully accessible to experiment. Utilizing steered molecular dynamics, we investigate the work required to move the Tm strand through the currently extant set of proposed transitions. We find that a longitudinal motion towards the pointed end of actin by Tm is most probable due to the topographical landscape of actin.
ASJC Scopus subject areas
- Materials Science(all)