Friday, 17 April, 2015
DNA-tile structures lead to ionic currents through lipid membranes
K. Göpfrich, T. Zettl, A.E.C. Meijering, S. Hernández-Ainsa, S. Kocabey, T. Liedl, and U.F. Keyser -
Nano Letters, DOI:10.1021/acs.nanolett.5b00189 (2015)
Self-assembled DNA nanostructures have been used to create man-made transmembrane channels in lipid bilayers. Here, we present a DNA-tile structure with a nominal sub-nanometer channel and cholesterol-tags for membrane anchoring. With an outer diameter of 5 nm and a molecular weight of 45 kDa, the dimensions of our synthetic nanostructure are comparable to biological ion channels. Due to its simple design, the structure self-assembles within a minute, making its creation scalable for applications in biology. Ionic current recordings demonstrate that the tile structures enable ion conduction through lipid bilayers and show gating and voltage-switching behaviour. By demonstrating the design of DNA-based membrane channels with openings much smaller than that of the archetypical six-helix bundle, our work showcases their versatility inspired by the rich diversity of natural membrane components.