Research

Membrane model systems

To study processes on cell membranes, and to elucidate the relationship between membrane proteins and the surrounding lipids, we devised cell-like model membrane systems mimicking the formation of membrane domains, whose cellular counterparts are potentially active, e.g., as recruitment platforms for signalling proteins.

This is particularly attractive in light of the so called “raft hypothesis”, suggesting that local lipid order might be an important constituent in membrane protein recruitment and functionality. Giant Unilamellar Vesicles (GUVs), in particular, represent a rapidly emerging model in membrane research. They are spherical closed single bilayers, freely floating in aqueous solution and thus, suitable for single-molecule optical microscopy, as they exhibit a cell-like curvature, with sizes ranging from 10 to several 100 µm in diameter.

Reconstituting functional proteins in these domain-exhibiting model systems, their activity can be studied in a controlled lipid environment, and the influence of local lipid order on protein function can be investigated. In reverse, the influence of protein activity (e.g., interactions or aggregation) on the organization of the lipidic system can be followed.