The Structural Basis for the Large Powerstroke of Myosin VI

@article{Mntrey2007TheSB,
  title={The Structural Basis for the Large Powerstroke of Myosin VI},
  author={Julie M{\'e}n{\'e}trey and Paola Llinas and Monalisa Mukherjea and H. Lee Sweeney and Anne Houdusse},
  journal={Cell},
  year={2007},
  volume={131},
  pages={300-308}
}
Due to a unique addition to the lever arm-positioning region (converter), class VI myosins move in the opposite direction (toward the minus-end of actin filaments) compared to other characterized myosin classes. However, the large size of the myosin VI lever arm swing (powerstroke) cannot be explained by our current view of the structural transitions that occur within the myosin motor. We have solved the crystal structure of a fragment of the myosin VI motor in the structural state that… Expand
A conformational transition in the myosin VI converter contributes to the variable step size.
Myosin VI (MVI) is a dimeric molecular motor that translocates backwards on actin filaments with a surprisingly large and variable step size, given its short lever arm. A recent x-ray structure ofExpand
Myosin VI dimerization triggers an unfolding of a three-helix bundle in order to extend its reach.
TLDR
The structure of the region immediately distal to the lever arm of the motor is determined and it is shown that it is a three-helix bundle and that this bundle unfolds upon dimerization of two myosin VI monomers. Expand
Processive steps in the reverse direction require uncoupling of the lead head lever arm of myosin VI.
TLDR
Structures of myosin VI are presented that reveal regions of compliance that allow an uncoupling of the lead head when movement is modeled on actin, and the location of the compliance restricts the possible actin binding sites and predicts the observed stepping behavior. Expand
Unique features of myosin VI: a structural view
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  • Biology
  • Frontiers in Biology
  • 2010
TLDR
The structural studies of myosin VI definitely provide some answers about the unique features of myOSin VI, but also raise significant questions on how myosIn VI functions as a special motor both for directional cargo transport and for structural anchoring. Expand
The post‐rigor structure of myosin VI and implications for the recovery stroke
TLDR
The structure of myosin VI with an ATP analogue (ADP.BeF3) bound in its nucleotide‐binding pocket reveals that no rearrangement in the converter occur upon ATP binding, and reveals novel features of the myosIn VI motor that may be important in maintaining the converter conformation during detachment from actin. Expand
Lever arm extension of myosin VI is unnecessary for the adjacent binding state
TLDR
The authors' chimera showed the same stepping patterns as myosin VI, indicating the LAE is not responsible for the adjacent binding state, and the parallel lever arms model, which is necessary for the unique motion. Expand
Kinematics of the lever arm swing in myosin VI
TLDR
A unique coarse-grained model for the power stroke of a single MVI is provided, providing the molecular basis for its motility and providing insights into the broad step-size distribution of MVI. Expand
Kinematics of the Lever Arm Swing in Myosin VI
TLDR
A new coarse-grained model for the power stroke of a single MVI provides the molecular basis for its motility and suggests that the leading-head lever arm of a MVI dimer is uncoupled, in accord with the inference drawn from polarized Total Internal Reflection Fluorescence experiments. Expand
Single-molecule studies of unconventional motor protein myosin VI
All rights reserved INFORMATION TO ALL USERS The quality of this reproduction is dependent on the quality of the copy submitted. In the unlikely event that the author did not send a completeExpand
Myosin VI Rewrites the Rules for Myosin Motors
TLDR
Understanding the design principles of myosin VI will help guide the study of the functions of the myosins that adopt similar strategies, given that other classes of myOSins may share some of these features. Expand
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The recently solved structure of the myosin VI motor demonstrates that the unique insert at the end of the motor is responsible for the reversal of the normal myosin directionality. A secondExpand
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