Mode of Myosin Transportation in Living Cells Studied by Single Particle Tracking

The transport of internalized ?1A-adrenergic receptor (?1A-AR) by myosin protein in live cells was studied. The technique of single particle tracking by °uorescence imaging with high temporal and spatial resolution was used. The endosomes of ?1A-AR were transported along actin ˉlaments in a step-by-step mode. The average step-size in di?erent time resolutions is consistent with the step-size of myosin assay in vitro. With the simulation of the stepwise traces in di?erent time resolutions, we found that the kinetic process of each step is in coherence with the single myosin assay in vitro.