Local heat activation of single myosins based on optical trapping of gold nanoparticles.
Myosin is a mechano-enzyme that hydrolyzes ATP in order to move unidirectionally along actin filaments. Here we show by single molecule imaging that myosin V motion can be activated by local heat. We constructed a dark-field microscopy that included optical tweezers to monitor 80 nm gold nanoparticles (GNP) bound to single myosin V molecules with nanometer and submillisecond accuracy. We observed 34 nm processive steps along actin filaments like those seen when using 200 nm polystyrene beads (PB) but dwell times (ATPase activity) that were 4.5 times faster. Further, by using DNA nanotechnology (DNA origami) and myosin V as a nanometric thermometer, the temperature gradient surrounding optically trapped GNP could be estimated with nanometer accuracy. We propose our single molecule measurement system should advance quantitative analysis of the thermal control of biological and artificial systems like nanoscale thermal ratchet motors.
†Quantitative Biology Center, RIKEN, Suita, Osaka 5650874, Japan.|‡Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka, 5650874, Japan.
Mitsuhiro
M
Iwaki
†Quantitative Biology Center, RIKEN, Suita, Osaka 5650874, Japan.|‡Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka, 5650874, Japan.
Atsuko H
AH
Iwane
§School of Frontier Sciences, The University of Tokyo, Kashiwa, Chiba, 2778561, Japan.
Keigo
K
Ikezaki
†Quantitative Biology Center, RIKEN, Suita, Osaka 5650874, Japan.|‡Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka, 5650874, Japan.|∥Center for Information and Neural Networks, NICT, Suita, Osaka, 5650874, Japan.
Toshio
T
Yanagida
D004247:DNA / Q000737:chemistry* / Q000648:ultrastructure; D006046:Gold / Q000737:chemistry; D006361:Heating / Q000379:methods*; D008422:Materials Testing / Q000379:methods; D053768:Metal Nanoparticles / Q000737:chemistry; D057054:Molecular Imaging / Q000379:methods*; D020409:Molecular Motor Proteins / Q000737:chemistry / Q000648:ultrastructure; D015336:Molecular Probe Techniques; D009218:Myosins / Q000737:chemistry* / Q000302:isolation & purification; D052898:Optical Tweezers; D013696:Temperature; D013817:Thermography / Q000379:methods*
D020409:Molecular Motor Proteins; D006046:Gold; D004247:DNA; D009218:Myosins
Motor protein; gold nanoparticle; local heating; optical trap; single molecule