This video shows configurations for a single protofilament and an associated ring subunit (Dam1 heterodecamer) for a ring-microtubule pair. Here, tubulin monomers are shown as green bars (separated with dots) that correspond to their vertical axes, so each linker ends approximately 2 nm away from the green line at the monomer's surface (shown as spheres on the first image only). The ring subunit and its linker move in 3D, but the movie shows only their 2D projection onto the plane of this protofilament. Each linker is predicted to walk in 8 nm steps along the same PF, just like a kinesin. In the current case, however, the energy for linker stepping comes from the protofilament bending to its equilibrium configuration. Although the individual linkers occasionally step backwards, the whole ring moves unidirectionally towards the MT minus endComponente Curricular::Educação Superior::Ciências Biológicas::Morfologia