Biochemistry Seminar: Tobias Baumgart: Mechanisms of Lipid Bilayer Membrane Curvature Generation
Tobias Baumgart, Professor, Dept of Chemistry, University of Pennsylvania, will give a talk on "Mechanisms of Lipid Bilayer Membrane Curvature Generation"
Membrane curvature has developed into a forefront of membrane biophysics. Numerous proteins involved in membrane curvature sensing and membrane curvature generation have recently been discovered, including proteins containing the crescent-shaped BAR domain as membrane binding and shaping module. Accordingly, the structure of these proteins and their multimeric complexes is increasingly well-understood.
Substantially less understood, however, are the detailed mechanisms of how these proteins interact with membranes in a curvature-dependent manner. New experimental approaches need to be combined with established techniques to be able to fill in these missing details. Furthermore, an integrated view of the membrane considering at least three conceptual layers is required in order to fully understand the plethora of mechanisms that can contribute to membrane bending. Here we use model membrane systems in combination with a variety of biophysical techniques to characterize mechanistic aspects of lipid membrane shaping, BAR domain protein function, and BAR protein / GPCR interactions at the membrane. This includes a characterization of membrane curvature sensing and membrane generation. We present an approach to investigate membrane curvature transitions, and introduce membrane shape stability diagrams as a powerful tool to enhance the mechanistic understanding of membrane trafficking phenomena, including endocytosis, with molecular detail.