Fig. 2: DNA-origami barrel monomers.
From: Complex multicomponent patterns rendered on a 3D DNA-barrel pegboard
a Agarose gel electrophoresis of five barrel designs. Lanes 4–8 are barrels with diameter–height in nm: 30–27, 30–65, 60–30, 90–19, 90–23. Controls are 1-kb ladder (250–10,000 bp, lanes 1, 11; reference bands marked for 1, 3, 6-kb dsDNA), and unfolded scaffold (7308-nt lanes 2, 10; 8634-nt lanes 3, 9). b Design and molecular microscopy of barrel monomers excised from agarose gels as in a and recovered by centrifugation. Imaging was performed via (middle) DNA-PAINT super-resolution fluorescence microscopy or (right) uranyl-formate negative-stain TEM. To prepare for DNA-PAINT imaging, monomers first were functionalized with 6, 12, 18 biotins on their bottom inner helices for upright attachment to streptavidin-coated glass surfaces, and 6, 12, 18 docking handles on one of the outer helices (for 30, 60, 90-nm diameter barrels, respectively; indicated by red dots in design schematic). DNA-PAINT images are given for a single structure (left) and as a summed image (right) of N = 726, N = 16, N = 27 particles for the 30, 60, 90-nm barrels, respectively. Design and measured diameters of barrels are indicated on panels for both imaging methods. Scale bars 50 nm.
