Blebbistatin Effects Expose Hidden Secrets in the Force-Generating Cycle of Actin and Myosin.

ABSTRACT: Cyclic interactions between myosin II motors and actin filaments driven by ATP turnover underlie muscle contraction and have key roles in the motility of nonmuscle cells. A remaining enigma in the understanding of this interaction is the relationship between the force-generating structural change and the release of the ATP-hydrolysis product, inorganic phosphate (Pi), from the active site of myosin. Here, we use the small molecular compound blebbistatin to probe otherwise hidden states and transitions in this process. Different hypotheses for the Pi release mechanism are tested by interpreting experimental results from in vitro motility assays and isolated muscle fibers in terms of mechanokinetic actomyosin models. The data fit with ideas that actomyosin force generation is preceded by Pi

SUBMITTER: Rahman MA 

PROVIDER: S-EPMC6050972 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature