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Updated: Jul 29, 2026

Myosin-Specific Adaptations of In vitro Fluorescence Microscopy-Based Motility Assays
Published on: February 4, 2021
On Myosin II dynamics in the presence of external loads
A Buonocore1, L Caputo, Y Ishii
1Dipartimento di Matematica e Applicazioni, Università di Napoli Federico II, Via Cintia, 80126 Napoli, Italy. aniello.buonocore@unina.it
Abstract:
We address the controversial hot question concerning the validity of the loose coupling versus the lever-arm theories in the actomyosin dynamics by re-interpreting and extending the phenomenological washboard potential model proposed by some of us in a previous paper. In this new model a Brownian motion harnessing thermal energy is assumed to co-exist with the deterministic swing of the lever-arm, to yield an excellent fit of the set of data obtained by some of us on the sliding of Myosin II heads on immobilized actin filaments under various load conditions. Our theoretical arguments are complemented by accurate numerical simulations, and the robustness of the model is tested via different choices of parameters and potential profiles.
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