Membrane curvature modulation by membrane fusion promoting domains: HHP as a tool to study membrane fusion

• Applicant: Professor Dr. Roland Winter, since 7/2016
• Subject Area: Physical Chemistry of Molecules, Liquids and Interfaces, Biophysical Chemistry
• Term: from 2013 to 2017
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 227612752

In biomembranes, the fluid lamellar phase is the dominant structural motif. However, understanding also the dynamics of lyotropic phase transitions from lamellar to non-lamellar phases, such as cubic phases, is of relevance in biological systems where membrane fusion and division occurs. There is evidence that intermediates in membrane fusion correspond to intermediates in the fluid lamellar/inverse bicontinuous cubic (Lα/QII) phase transition, which can be induced by pressure perturbation. We are planning to investigate the tendency of lipids to form fusion pore structures (QII phase precursors) upon addition of fusion peptides (FPs) and transmembrane domains (TMDs) from viral fusion proteins. The proposed project aims to correlate the distinct structural properties of the peptides from different viral fusion protein classes with their ability to modulate membrane curvature. Models for the interaction mechanism of the different FPs and TMDs with the target membrane based on theories of membrane fusion and existing knowledge of the structure and energetics of bicontinuous cubic phases will be assessed. Delineating the intricacy of pressure-induced lipid-fusion protein interaction will help us to understand membrane fusion events also under extreme environmental conditions, such as encountered in deep sea environments.

• DFG Programme: Research Units
• Subproject of: FOR 1979: Exploring the Dynamical Landscape of Biomolecular Systems by Pressure Perturbation
• Ehemalige Antragstellerin: Dr. Katrin Weise, until 6/2016