Using electrical and optical tweezers to facilitate studies of molecular motors

作者：Arsenault Mark E; Sun Yujie; Bau Haim H; Goldman Yale E^*

来源：Physical Chemistry Chemical Physics, 2009, 11(24): 4834-4839.

DOI：10.1039/b821861g

Dielectrophoresis was used to stretch and suspend actin. laments 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. lament, facilitating the attachment of the myosin-coated bead to the. lament. The clearance beneath the. lament allowed the bead to move freely along and around its. lamentous 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.

• 出版日期2009