Myosin X Is a High Duty Ratio Motor*

  title={Myosin X Is a High Duty Ratio Motor*},
  author={Kazuaki Homma and Mitsuo Ikebe},
  journal={Journal of Biological Chemistry},
  pages={29381 - 29391}
  • K. Homma, M. Ikebe
  • Published 12 August 2005
  • Biology, Chemistry
  • Journal of Biological Chemistry
Myosin X is expressed in a variety of cell types and plays a role in cargo movement and filopodia extension, but its mechanoenzymatic characteristics are not fully understood. Here we analyzed the kinetic mechanism of the ATP hydrolysis cycle of acto-myosin X using a single-headed construct (M10IQ1). Myosin X was unique for the weak “strong actin binding state” (AMD) with a Kd of 1.6 μm attributed to the large dissociation rate constant (2.1 s-1). Vmax and KATPase of the actin-activated ATPase… 

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A Unique ATP Hydrolysis Mechanism of Single-headed Processive Myosin, Myosin IX*

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