Probing single processive molecular motors with high-speed optical tweezers and fluorescence microscopy
Authors: Gardini L., Pavone FS., Capitanio M.
Autors Affiliation: Univ Florence, LENS European Lab Nonlinear Spect, Via Nello Carrara 1, I-50019 Sesto Fiorentino, Italy; Univ Florence, Dept Phys & Astron, Via Sansone 1, I-50019 Sesto Fiorentino, Italy; INO, Largo Fermi 6, I-50125 Florence, Italy
Abstract: Here we present development of optical techniques for the study of single processive myosin motors based on the combination of high-speed optical tweezers force spectroscopy and single molecule fluorescence imaging. Ultrafast force-clamp spectroscopy(1) is applied to study the dependence of single chemo-mechanical steps of processive myosin motors on the applied load. On the other hand, single molecule localization through FIONA (Fluorescence Imaging with One Nanometer Accuracy)(2, 3) is applied to in vitro motility assay to measure parameters such as the runlength, velocity and step size of single myosin V motors, labeled with Quantum Dots, under unloaded conditions.
KeyWords: molecular motors; single molecule force-clamp spectroscopy; single molecule nanometer localization; Quantum Dots