Cells use membrane proteins as gatekeepers to transport ions and molecules, catalyze reactions, relay signals, and interact with other cells. DNA nanostructures with lipidic anchors are promising as membrane protein mimics because of their high tuneability. However, the design features specifying DNA nanostructure's functions in lipid membranes are yet to be fully understood. Here, we show that altering patterns of cholesterol units on a cubic DNA scaffold dramatically changes its interaction mode with lipid membranes. This results in simple design rules that allow a single DNA nanostructure to reproduce multiple membrane protein functions: peripheral anchoring, nanopore behavior and conformational switching to reveal membrane-binding units. Strikingly, the DNA-cholesterol cubes constitute the first open-walled DNA nanopores, as only a quarter of their wall is made of DNA. This functional diversity can increase our fundamental understanding of membrane phenomena, and results in sensing, drug delivery and cell manipulation tools. ASSOCIATED CONTENT Supporting Information. This material is available free of charge via the Internet at http://pubs.acs.org. DNA cage design and assembly, lipid vesicle preparation, membrane-binding study, dye-influx assay and molecular dynamic simulations.

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A series of CuS nanostructures were synthesized by a simple wet chemical method on a large scale in the presence of cetyltrimethylammonium bromide at low temperature. Three typical samples were selected to study the relationship between the morphologies and resulting physical properties. The optical properties of CuS hierarchical structures were investigated by UV/Vis and Raman spectroscopy and the excellent photocatalytic performance was also evaluated by measuring the decomposition rate of methylene blue under natural light. As an absorber, the selected CuS nanostructures possess excellent microwave absorbing properties. When the thickness of the absorber is 3.5 mm, the minimum reflection loss can reach −76.4 dB at 12.64 GHz. The enhanced photocatalytic performance and microwave absorbing properties were also explained based on morphologies of the nanostructures.

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Nucleobase mimicking small molecules able to reconfigure DNA are a recently discovered strategy that promises to extend the structural and functional diversity of nucleic acids. However, only simple, unfunctionalized molecules such as cyanuric acid and melamine have so far been used in this approach. In this work, we show that the addition of substituted cyanuric acid molecules can successfully program polyadenine strands to assemble into supramolecular fibers. Unlike conventional DNA nanostructure functionalization, which typically end-labels DNA strands, our approach incorporates functional groups into DNA with high density using small molecules and results in new DNA triple helices coated with alkylamine or alcohol units that grow into micrometer-long fibers. We find that small changes in the small molecule functional group can result in large structural and energetic variation in the overall assembly. A combination of circular dichroism, atomic force microscopy, molecular dynamics simulations, and a new thermodynamic method, transient equilibrium mapping, elucidated the molecular factors behind these large changes. In particular, we identify substantial DNA sugar and phosphate group deformations to accommodate a hydrogen bond between the phosphate and the small-molecule functional groups, as well as a critical chain length of the functional group which switches this interaction from intra- to interfiber. These parameters allow the controlled formation of hierarchical, hybrid DNA assemblies simply through the addition and variation of small, functionalized molecules.