18 Nov 2011
François Nédélec
Cell Biology and Biophysics
European Molecular Biology Laboratory (EMBL)
In a "gliding assay" cytoskeletal fibers are propelled by molecular motors immobilized on a substrate. When the motors are uniformly distributed on the substrate, the path of the fibers is usually tortuous, and they move equally in all directions. To use the motion of these fibers for example in a micro-device, it is however necessary to be able to direct the fibers in a particular direction. Different techniques have been proposed to achieve this, for instance using external forces or surrounding the fibers with ratchet-like walls. In this lecture, we will argue that sparsely positioning motors over a flat surface is sufficient to precisely control the direction of fiber motility. We will present different patterns on which the motion of the fibers is directed, and we will also brainstorm together to see if we can discover more patterns. We will also discuss ways to sort apart fibers of different length. The conclusion will be that the fibers can be controlled at will, provided that one is able to pattern motors with precision on the substrate.