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Quantum Dot Labeling Strategies to Characterize Single-Molecular Motors

  • Shane R. NelsonEmail author
  • M. Yusuf Ali
  • David M. Warshaw
Protocol
Part of the Methods in Molecular Biology book series (MIMB, volume 778)

Abstract

Recent advances in single-molecule labeling and detection techniques allow high-resolution imaging of the motion of single molecules. Molecular motors are biological machines that convert chemical energy into mechanical work. Myosin Va (MyoVa) is a well-characterized processive molecular motor, essential for cargo transport in living organisms. Quantum dots (Qdots) are fluorescent semiconductor nanocrystals that are extremely useful for single-molecule studies in biological sciences. High-resolution video microscopy and single-particle tracking of a Qdot-labeled MyoVa motor molecule allow the detection of individual steps in vitro and in live cells.

Key words

Single molecule Myosin Actin Total Internal Reflection Microscopy Single-Particle Tracking Steps 

Notes

Acknowledgments

The authors thank Guy Kennedy for optomechanical support, Samantha Previs for technical expertise, and Kathleen Trybus for providing MyoVa protein. This work was supported by funds from the National Institutes of Health HL007944 (to S.R.N.) and HL059408, GM094229, and HL085489 (to D.M.W.).

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Copyright information

© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  • Shane R. Nelson
    • 1
    Email author
  • M. Yusuf Ali
    • 1
  • David M. Warshaw
    • 1
  1. 1.Department of Molecular Physiology and BiophysicsUniversity of Vermont College of MedicineBurlingtonUSA

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