CYTOCUT · Cytokinesis’ final cut: mechanics of abscission and ESCRT-III mediated membrane fission

Abscission is the ultimate event of cytokinesis during which the intracellular bridge connecting two daughter cells is irreversibly cleaved. Reports show that a complex called ESCRT-III is involved in plasma membrane fission during abscission. The goal of this project is to understand how membrane mechanics can influence the fate of cytokinesis both at the molecular and at the cellular levels.First, I will address the mechanism of ESCRT-III mediated membrane fission by using in vitro assays mimicking abscission geometry. I will study protein and lipid composition necessary for fission, as well as its dynamics and mechanical requirements by controlling membrane tension.For the in vivo study, I will build a double pipette setup whose goal is to hold dividing cells, allowing to precisely visualize abscission in real time. Abscission mechanism will be addressed by controlling and measuring mechanical stress applied on cells in cytokinesis in combination with RNAi knock-down of ESCRT-III proteins.By comparing in vivo and in vitro results, the ultimate goal will be to uncover the relation between abscission, ESCRT-III mediated membrane fission and cell mechanics.""