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Velocity, processivity, and individual steps of single myosin V molecules in live cells.

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.

SUBMITTER: Pierobon P

PROVIDER: S-EPMC2712235 | biostudies-literature | 2009 May

REPOSITORIES: biostudies-literature

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Velocity, processivity, and individual steps of single myosin V molecules in live cells.

Pierobon Paolo P Achouri Sarra S Courty Sébastien S Dunn Alexander R AR Spudich James A JA Dahan Maxime M Cappello Giovanni G

Biophysical journal 20090501 10

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 a ...[more]

PMID: 19450497

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