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High-resolution structures of the actomyosin-V complex in three nucleotide states provide insights into the force generation mechanism.

ABSTRACT: The molecular motor myosin undergoes a series of major structural transitions during its force-producing motor cycle. The underlying mechanism and its coupling to ATP hydrolysis and actin binding are only partially understood, mostly due to sparse structural data on actin-bound states of myosin. Here, we report 26 high-resolution cryo-EM structures of the actomyosin-V complex in the strong-ADP, rigor, and a previously unseen post-rigor transition state that binds the ATP analog AppNHp. The structures reveal a high flexibility of myosin in each state and provide valuable insights into the structural transitions of myosin-V upon ADP release and binding of AppNHp, as well as the actomyosin interface. In addition, they show how myosin is able to specifically alter the structure of F-actin.

SUBMITTER: Pospich S

PROVIDER: S-EPMC8735999 | biostudies-literature | 2021 Nov

REPOSITORIES: biostudies-literature

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High-resolution structures of the actomyosin-V complex in three nucleotide states provide insights into the force generation mechanism.

Pospich Sabrina S Sweeney H Lee HL Houdusse Anne A Raunser Stefan S

eLife 20211123

The molecular motor myosin undergoes a series of major structural transitions during its force-producing motor cycle. The underlying mechanism and its coupling to ATP hydrolysis and actin binding are only partially understood, mostly due to sparse structural data on actin-bound states of myosin. Here, we report 26 high-resolution cryo-EM structures of the actomyosin-V complex in the strong-ADP, rigor, and a previously unseen post-rigor transition state that binds the ATP analog AppNHp. The struc ...[more]

PMID: 34812732

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