Synthetic Cells, Reconstitution of a Minimal Cortex

To decipher the relative contributions of the membrane and cortex to cells, we built a minimal cortex inside a giant unilamellar vesicle and compared the mechanics of the synthetic cell to those of wild type cells and cells where we progressively removed important cytoskeletal components.  By comparing the reconstituted cell with the 'deconstituted' cell, we found that the membrane contributed no more than 2% to total cell mechanics.  This maximum places important limitations on what membrane can contribute to cell mechanics.  For example, in cells where the membrane and cortex are tightly coupled, the cytoskeleton will bear nearly all of the load.  In cells that have loose coupling between the membrane and cortex, the membrane will be more sensitive to small stresses, though it still cannot bear much load without tearing.  For more details, please see Luo et al. App. Phys. Lett. 2014