Dynamics of the unbound head during myosin V processive translocation

Alexander R Dunn, James A Spudich
2007 Nature Structural & Molecular Biology  
Myosin V moves cargoes along actin filaments by walking hand over hand. Although numerous studies support the basic hand-over-hand model, little is known about the fleeting intermediate that occurs when the rear head detaches from the filament. Here we use submillisecond dark-field imaging of gold nanoparticle-labeled myosin V to directly observe the free head as it releases from the actin filament, diffuses forward and rebinds. We find that the unbound head rotates freely about the lever-arm
more » ... out the lever-arm junction, a trait that likely facilitates travel through crowded actin meshworks.
doi:10.1038/nsmb1206 pmid:17293871 fatcat:pjdaaadfevdrtls3zgqhnvjobe