Related Experiment Video

Updated: Jul 18, 2026

Dissecting Mechanoenzymatic Properties of Processive Myosins with Ultrafast Force-Clamp Spectroscopy
09:38

Dissecting Mechanoenzymatic Properties of Processive Myosins with Ultrafast Force-Clamp Spectroscopy

Published on: July 1, 2021

Myosin-V is a processive actin-based motor

A D Mehta1, R S Rock, M Rief

  • 1Department of Biochemistry, Stanford University Medical Center, California 94305, USA.

Nature
|August 17, 1999
PubMed

Insights

Class-V myosins are processive molecular motors, meaning single motors can move organelles along actin tracks. This study provides direct evidence of myosin-V

Area of Science:

  • Cell biology
  • Molecular motors
  • Cytoskeletal dynamics

Background:

  • Class-V myosins are actin-based molecular motors involved in organelle transport.
  • Their mechanochemical properties may differ from myosin-II, which functions in ensembles.
  • Myosin-V is hypothesized to be a processive motor, similar to kinesin.

Purpose of the Study:

  • To provide direct evidence for the processivity of myosin-V.
  • To characterize the motile properties of myosin-V as an actin-based motor.

Main Methods:

  • Investigated the movement of myosin-V along actin filaments.
  • Analyzed the step size and catalytic cycles of individual myosin-V motors.

Main Results:

  • Demonstrated that myosin-V is a processive motor.
  • Showed that myosin-V moves in large steps, approximately 36 nm, along actin filaments.

Conclusions:

  • Myosin-V functions as a processive motor, capable of single-motor organelle transport.
  • The large step size of myosin-V is consistent with its role in cargo movement along actin.

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