2023 Volume 63 Issue 2 Pages 86-90
Kinesin-1, a molecular motor that transports intracellular vesicles, has been proposed to achieve efficient unidirectional movements, by utilizing thermal fluctuations. However, our previous study revealed that kinesin was less efficient than expected, by measuring the work/dissipation during their motion in vitro. We thus hypothesized that kinesin is optimized for the intracellular environment, rather than for in vitro experimental conditions. This review briefly describes the difference between in vitro and in cells, focusing on nonthermal fluctuations that occur in living cells. We then introduce our recent findings that kinesin moves faster under external force fluctuations that mimic the intracellular environment.
