Departmental Papers (MEAM)

Document Type

Journal Article

Date of this Version



Suggested Citation:
Arsenault, Mark E., Yujie Sun, Haim H. Bau, Yale E. Goldman. (2009). Using electrical and optical tweezers to facilitate studies of molecular motors. Physical Chemistry Chemical Physics. Vol. 11, 4834–4839.

Reprinted by permission from The Royal Society of Chemistry (RSC). DOI: 10.1039/B821861G


Dielectrophoresis was used to stretch and suspend actin filaments across a trench etched between two electrodes patterned on a glass slide. Optical tweezers were used to bring a motor protein-coated bead into close proximity to a pre-selected, suspended actin filament, facilitating the attachment of the myosin-coated bead to the filament. The clearance beneath the filament allowed the bead to move freely along and around its filamentous track, unhindered by solid surfaces. Using defocused images, the three-dimensional position of the bead was tracked as a function of time to obtain its trajectory. Experiments were carried out with myosin V and myosin X. Both motor proteins followed left-handed helical paths with the myosin X motor exhibiting a shorter pitch than the myosin V. The combined use of electrostatic and optical tweezers facilitates the preparation of motility assays with suspended tracks. Variants of this technique will enable higher complexity experiments in vitro to better understand the behavior of motors in cells.



Date Posted: 17 August 2010

This document has been peer reviewed.