Cytokinetic abscission mediated by the ESCRT complex

Conserved from archaea to mammals, the ESCRT III filamentous system executes membrane constriction and fission in a variety of processes in cells. Yet, the mechanism and regulation of ESCRT-driven membrane fission in intact cells is still unresolved. In cytokinetic abscission of mammalian cells, a 1micron wide membrane bridge is constricted and cut within approximately 20 minutes. The large-scale, ESCRT III-dependent, membrane constriction that occurs during abscission, offers an attractive model system to visualize ESCRTs in physiological context. We employ a variety of high resolution imaging techniques to study the ultrastructural organization of the ESCRT complex during abscission. Using data from Soft-X-ray tomography and 3D STORM we resolve structural evolution of the ESCRT-III complex during membrane constriction and fission in cells at nanoscale resolution. With this information in hand, we aim to unlock the mechanism of this ancient molecular machine.