Dynamic Alignment and Millimeter-scale Vortex Formation of Microtubules Driven by Different Types of Dynein

Experimental systems have long been demanded for the study of collective motion often observed in biology (a flock of birds, a shoal of fish, cell migrations during development etc). In vitro motility assays commonly used in biophysical studies on protein-motors now fulfill the demand described above. Using the in vitro motility assays, we report collective motion and vortex emergence of microtubules (MTs) driven by some subspecies of axonemal dyneins and find that under some experimental conditions, the collective motion of MTs can display nematic order, millimeter-scale meandering streams or millimeter-scale vortices. To explore the conditions causing such phase-shifts, we examine the effects of mechanical properties of dyneins on the pattern formation.