The structural basis for the large powerstroke of myosin VI

Cell. 2007 Oct 19;131(2):300-8. doi: 10.1016/j.cell.2007.08.027.

Abstract

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 represents the starting point for movement on actin; the pre-powerstroke state. Unexpectedly, the converter itself rearranges to achieve a conformation that has not been seen for other myosins. This results in a much larger powerstroke than is achievable without the converter rearrangement. Moreover, it provides a new mechanism that could be exploited to increase the powerstroke of yet to be characterized plus-end-directed myosin classes.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Actin Cytoskeleton / metabolism
  • Animals
  • Crystallography, X-Ray
  • Models, Molecular*
  • Molecular Motor Proteins / chemistry*
  • Molecular Motor Proteins / metabolism
  • Myosin Heavy Chains / chemistry*
  • Myosin Heavy Chains / metabolism
  • Myosin Subfragments / chemistry*
  • Myosin Subfragments / metabolism
  • Protein Conformation
  • Swine

Substances

  • Molecular Motor Proteins
  • Myosin Subfragments
  • myosin VI
  • Myosin Heavy Chains

Associated data

  • PDB/2V26
  • PDB/R2V26SF