EVOGENE Seminar - Surface-adhered biomembranes: A physiochemical toolbox to investigate the biological phenomena
Irep Gözen, The Biotechnology Centre
I will describe the generation, characterization and uses of a peculiar type of solid-supported model membrane: the self-spreading double bilayer. This type of solid-supported model membrane combines features and properties of a 2D lipid bilayer membrane, and a 3D phospholiposome. The double bilayer membrane, i.e., a fully closed, parallel stack of two lipid bilayers, is essentially a surface-adhered flat giant unilamellar vesicle with a very small internal volume. I will explain how this structure can be manipulated to probe and migrate upon chemical or physical cues, and display dynamic features reminiscent of complex cell behavior. A number of examples will be shown, including formation of filopodia-like protrusions and ER-like lipidic networks as a response to chemical gradients; directed and reversible movement in a temperature gradient. I will also talk about the discovery of two non-trivial pore formation modes in membranes, which links biomembrane materials properties to fundamental properties of thin solid materials. One of the modes displays crackling noise dynamics, featuring sudden intermittent bursts over a broad size range (avalanches), similar to earthquakes. I will finalize my talk showing how lipid membranes can be written on and deleted from solid substrates by using a microfluidic 'biopen'. I consider flat unilamellar vesicles as an experimental model system for studying various aspects of cell behavior as well as a nanotechnological platform, useful to construct mesoscale membrane architectures and networks.