Melanosomes transported by myosin-V in Xenopus melanophores perform slow 35 nm steps.
- Author(s): Levi, Valeria
- Gelfand, Vladimir I
- Serpinskaya, Anna S
- Gratton, Enrico
- et al.
Published Web Locationhttps://doi.org/10.1529/biophysj.105.075556
We studied the motion of pigment organelles driven by myosin-V in Xenopus melanophores using a tracking technique with precision of 2 nm. The organelle trajectories showed occasional steps with a distribution centered at 35 nm and a standard deviation of 13 nm, in agreement with the step size of myosin-V determined in vitro. In contrast, trajectories of melanosomes in cells expressing a dominant negative form of myosin-V did not show steps. The step duration was in the range 20-80 ms, slower than what it would be expected from in vitro results. We speculate that the cytoplasm high viscosity may affect significantly the melanosomes' motion.