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Updated: Jun 23, 2026

Myosin-Specific Adaptations of In vitro Fluorescence Microscopy-Based Motility Assays
Published on: February 4, 2021
Velocity, processivity, and individual steps of single myosin V molecules in live cells
Paolo Pierobon1, Sarra Achouri, Sébastien Courty
1Institut Curie, Centre de Recherche, Laboratoire Physico-Chimie Curie, Centre National de la Recherche Scientifique, UMR 168, Université Pierre et Marie Curie-Paris, Paris, France.
Abstract:
We report the tracking of single myosin V molecules in their natural environment, the cell. Myosin V molecules, labeled with quantum dots, are introduced into the cytoplasm of living HeLa cells and their motion is recorded at the single molecule level with high spatial and temporal resolution. We perform an intracellular measurement of key parameters of this molecular transporter: velocity, processivity, step size, and dwell time. Our experiments bridge the gap between in vitro single molecule assays and the indirect measurements of the motor features deduced from the tracking of organelles in live cells.
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