Synthetic Membrane Curvature-Inducing DNA Origami Scaffolds

Abstract

Biological membranes are dynamic cellular barriers that suffer deformation and bending. Despite huge effort in identifying the general elements involved in membrane curvature, the physical-chemical basis of curvature induction is still poorly understood. In this work, we fill this gap by engineering a minimal curvature-inducing system. Due to its exclusive nanoengineering properties, DNA origami technology will be utilized to build minimal curvature-inducing scaffoldings. This state-of-the-art technology enables the folding of long strands of DNA into nano-objects with defined shapes by using sequence-specific short DNA staples. For instance, our group recently constructed membrane-interacting rod-like DNA origami structures, which were functionalized with hydrophobic anchors and fluorescently labeled at defined positions [1]. Here, synthetic nanostructures will be designed in order to have a) defined customized shapes and b) specific membrane binding elements. Hybrid origami scaffolds with specific functional membrane-attachment groups bound at defined positions on the scaffolds will be produced. The interaction of those hybrid scaffolds with lipid membrane model systems will be studied and their capability of inducing membrane curvature evaluated. Fluorescence microscopy and atomic force microscopy methods will be used in order to retrieve extent, localization and forces involved in the interactions. More precisely, the role of the scaffolding shapes, membrane-attachment moieties, oligomerization and conformational changes will be assessed. At the end, this quantitative characterization of minimal membrane-inducing scaffolds will help understand the role of cooperativity in membrane deformation and the rules that govern the induction of membrane curvature.[1] A. Czogalla, E. P. Petrov, D. J. Kauert, V. Uzunova, Y. Zhang, R. Seidel, and P. Schwille, Faraday Discuss. 161 (2013) 31.