Seminar

 Motor proteins participate in intracellular transport and can generate mechanical forces on cytoskeletal filaments. In the first part of the talk, we will describe the impact of ubiquitination and its absence on UNC-104, a Kinesin-3 motor in C. elegans that transports synaptic vesicles. The study uses RNAi, live animal imaging, and coarse-grained theory. While the transport properties of the motors remain unaffected, the lack of ubiquitination increases cooperative cargo binding. In the second part, we will consider deformations of biopolymers and membranes under the active drive of motor proteins. We use analytic theory and numerical simulations for this purpose. Semiflexible filaments undergo re-entrant morphological transitions from open chain to spiral conformations in a gliding assay. On the other hand, a spherical cell membrane coupled to curvature-inducing activator proteins and active forces from polymerizing actin and myosin pull shows instabilities towards pattern formation and localized/running pulsations.