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Random walk of processive, quantum dot-labeled myosin Va molecules within the actin cortex of COS-7 cells.

ABSTRACT: Myosin Va (myoVa) is an actin-based intracellular cargo transporter. In vitro experiments have established that a single myoVa moves processively along actin tracks, but less is known about how this motor operates within cells. Here we track the movement of a quantum dot (Qdot)-labeled myoVa HMM in COS-7 cells using total internal reflectance fluorescence microscopy. This labeling approach is unique in that it allows myoVa, instead of its cargo, to be tracked. Single-particle analysis showed short periods (

SUBMITTER: Nelson SR

PROVIDER: S-EPMC2711322 | biostudies-literature | 2009 Jul

REPOSITORIES: biostudies-literature

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Random walk of processive, quantum dot-labeled myosin Va molecules within the actin cortex of COS-7 cells.

Nelson Shane R SR Ali M Yusuf MY Trybus Kathleen M KM Warshaw David M DM

Biophysical journal 20090701 2

Myosin Va (myoVa) is an actin-based intracellular cargo transporter. In vitro experiments have established that a single myoVa moves processively along actin tracks, but less is known about how this motor operates within cells. Here we track the movement of a quantum dot (Qdot)-labeled myoVa HMM in COS-7 cells using total internal reflectance fluorescence microscopy. This labeling approach is unique in that it allows myoVa, instead of its cargo, to be tracked. Single-particle analysis showed sho ...[more]

PMID: 19619465

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