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Spontaneous detachment of the leading head contributes to myosin VI backward steps.

ABSTRACT: Myosin VI is an ATP driven molecular motor that normally takes forward and processive steps on actin filaments, but also on occasion stochastic backward steps. While a number of models have attempted to explain the backwards steps, none offer an acceptable mechanism for their existence. We therefore performed single molecule imaging of myosin VI and calculated the stepping rates of forward and backward steps at the single molecule level. The forward stepping rate was proportional to the ATP concentration, whereas the backward stepping rate was independent. Using these data, we proposed that spontaneous detachment of the leading head is uncoupled from ATP binding and is responsible for the backward steps of myosin VI.

SUBMITTER: Ikezaki K

PROVIDER: S-EPMC3601099 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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Spontaneous detachment of the leading head contributes to myosin VI backward steps.

Ikezaki Keigo K Komori Tomotaka T Yanagida Toshio T

PloS one 20130318 3

Myosin VI is an ATP driven molecular motor that normally takes forward and processive steps on actin filaments, but also on occasion stochastic backward steps. While a number of models have attempted to explain the backwards steps, none offer an acceptable mechanism for their existence. We therefore performed single molecule imaging of myosin VI and calculated the stepping rates of forward and backward steps at the single molecule level. The forward stepping rate was proportional to the ATP conc ...[more]

PMID: 23527046

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