My main research activity revolves around the understanding of membrane remodeling by cytoskeletal proteins, septins more particularly. Septins are proteins bound to the inner plasma membrane that are necessary for the last step of cell division, cytokinesis. They act as a diffusion barrier at the site of constriction between two dividing cells and recruit essential partners (ESCRT-III, myosin...). I mainly use in-vitro approaches on reconstituted membrane-protein systems. Thus, it is possible to control the composition of the system (lipids, proteins, ionic environment) and to dissect the specific functions of the different partners. To this end I mainly use electron microscopy tools. Three-dimensional reconstructions describing the organization of the reconstituted systems in vitro are obtained by cryo-electron tomography. Additional structural details are obtained by tomogram sub-averagingThese approaches are coupled with scanning electron microscopy, fluorescence microscopy or atomic force microscopy methods through collaborations.