Lipid bilayers and lipid-associated proteins play a crucial role in biology. Since studies and manipulation in vivo are inherently challenging, several in vitro membrane-mimetic systems have been developed to enable the study of lipidic phases, lipid-protein interactions and membrane protein function. Controlling the size and shape or introducing functional elements in a programmable way is, however, difficult to achieve with common systems based on polymers, peptides or membrane scaffolding proteins. We have combined DNA-nanotechnology with lipid bilayer self-assembly to create DNA-encircled bilayers (DEBs) as a novel nano-scaled membrane-mimetic. For this, alkylated oligonucleotides were hybridized to a single-stranded minicircle (ssMC) to provide an inner hydrophic surface for lipid attachment. DEBs open new routes to membrane biophysical studies, enabling improved size control, stability and programmability. Here, we present further developments of DNA-associated lipid bilayers for the reconstitution of membrane proteins and for the generation of self-assembled higher order structures. The latter may be ultimately used for the structural biology of membrane proteins in Cryo-EM or in diffraction experiments using advanced X-ray sources, such as synchrotrons or XFELs.
- K. Iric, M. Subramanian, et al. Nanoscale 10 (2018) 18463-18467