Membrane remodeling in life processes: Unravelling membrane interactions, one vesicle at a time.

Fundamental understanding of physiological processes that occur at biological membranes, such as membrane fusion, necessitates addressing not only of the biochemical aspects but also membrane mechanical properties and membrane deformation. In this talk, I will show how we combine a system of optical tweezers dedicated to accurate force measurements with confocal fluorescence microscopy to study membrane remodelling by calcium sensor proteins, which are crucial in neuronal communication. Using this setup, we discovered surprising differences between the action mechanisms of two structurally similar proteins, Doc2b and Synaptotagmin1 (Syt1), as determined by quantifying the strength and probabilities of protein-induced membrane-membrane interactions and lipid and content mixing assays. I will further describe how we use this approach to gain insight into the fusion mechanisms of enveloped viruses with host cell membranes.