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bioRxiv · 10.1101/2021.12.22.473854

A synthetic membrane shaper for controlled liposome deformation

De Franceschi, N.·Pezeshkian, W.·Fragasso, A.·Bruininks, B.·Tsai, S.·Marrink, S.-J.·Dekker, C.
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Abstract

Shape defines the structure and function of cellular membranes. In cell division, the cell membrane deforms into a dumbbell shape, while organelles such as the autophagosome exhibit stomatocyte shapes. Bottom-up in vitro reconstitution of protein machineries that stabilize or resolve the membrane necks in such deformed liposome structures is of considerable interest to characterize their function. Here we develop a DNA-nanotechnology-based approach that we call Synthetic Membrane Shaper (SMS), where cholesterol-linked DNA structures attach to the liposome membrane to reproducibly generate high yields of stomatocytes and dumbbells. In silico simulations confirm the shape-stabilizing role of the SMS. We show that the SMS is fully compatible with protein reconstitution by assembling bacterial divisome proteins (DynaminA, FtsZ:ZipA) at the catenoidal neck of these membrane structures. The SMS approach provides a general tool for studying protein binding to complex membrane geometries that will greatly benefit synthetic cell research.

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De Franceschi, N., Pezeshkian, W., Fragasso, A., Bruininks, B., Tsai, S., Marrink, S.-J., Dekker, C.. 2021-12-23. A synthetic membrane shaper for controlled liposome deformation. https://doi.org/10.1101/2021.12.22.473854

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