The dynamin family of proteins contains unique GTPases involved in membrane fission and fusion events throughout the cell. Dynamin is necessary for internalizing essential nutrients, is tightly coupled to cell signalling events, and has been linked to neuropathies and myopathies. As a vesicle invaginates, dynamin forms a spiral around the neck of the vesicle generating dynamin-lipid tubes that constrict and twist upon GTP hydrolysis, causing the vesicle neck to break (play video on the left). The ability of dynamin to constrict mechanically the underlying lipid bilayer makes it unique among GTPases as a mechano-chemical enzyme. However, the mechano-chemical processes governing the operation of dynamins at the molecular level are still under debate.
In collaboration with the laboratory of Prof. Vadim Frolov we are using optical tweezers to developed an assay to measure the real-time activities of Dynamin 1 and Dynamin 2 proteins as they constrict single membrane nanotubes. These experiements will allow us to determine the effect of GTP analogues on their reactions and will therefreo, shed light into the mechanical operation of these enzymes.