Mona Lisa made from Programmable Fractal DNA-Origami

Ich schrieb in den bezahlten Anzeigen für den BR und seine Futurismus-Webserie Homo Digitalis viel über CRISPR – add this to the equation: Nature hat zum Nikolaus gleich 4 Papers zu selbstzusammenbauenden DNA-Origami veröffentlicht und in einem bauen sie eine Mona Lisa aus angeordneten Tiles bestehend aus DNA-Fraktal-Pixeln. Außerdem „a clipart-rooster, a bacterium, a photoreceptor circuit31 and a chess game, generated using the compiler, either converted and modified from an uploaded image directly or drawn manually using the ‘modify layout’ function.“ Und noch dazu haben sie eine DNA-Designsoftware namens FracTile entwickelt, mit der auch Biotech-Noobs fraktale DNA-Origami bauen können.

Außerdem bauen sie bereits Röhren aus DNA-„Ring Oligomers“, Teddybären aus literally DNA-Lego-Bricks aka „Three-dimensional nanostructures self-assembled from DNA bricks“ und DNA-Origami Massenproduktion. Welcome to the new Flesh.

DNA self-assembly scaled up: „DNA can be designed to self-assemble into target shapes, but the size and quantity of objects that can be prepared have been limited. Methods to overcome these problems have now been found.“

Tikhomirov et al.2 (page 67) used square DNA origami decorated with surface patterns (formed by DNA strands that extend from the origami surface) as building units to create 2D DNA origami arrays up to about half a micrometre across (Fig. 1a). The square origami join together through the formation of short DNA duplexes at their interfaces. To program the interactions between the square origami, the authors developed a fractal method in which local assembly rules were used recursively in a hierarchical, multi-step process that assembles increasingly large arrays of the square origami. Tikhomirov and colleagues also produced design software called FracTile Compiler, which will enable non-experts to devise DNA sequences and experimental procedures to make large DNA patterns. The authors validated this automated design process by using it to make several DNA ‘pictures’, including the Mona Lisa, a rooster and a chess-game pattern (see Fig. 3 of the paper2).

Wagenbauer et al.3 (page 78) have made 3D DNA origami structures at sizes up to the micrometre scale, using another hierarchical self-assembly approach (Fig. 1b). They used a V-shaped DNA origami object as the basic building block, in which the angle of the V could be altered. By controlling the geometry and interactions between the building blocks, higher-order assemblies can be constructed. The authors demonstrated the capabilities of their method by constructing micrometre-long tubes (similar in size to some bacteria) out of stacked planar rings up to 350 nm in diameter, and three types of polyhedron up to 450 nm in diameter.

Ong et al.4 (page 72) report a method that allows 3D SST DNA constructs to be made at the micrometre scale (Fig. 1c). By extending the principles of first-generation SST systems, the authors designed a brick-shaped DNA building block composed of 52 nucleotides, which contains four 13-nucleotide binding domains. These domains enable the bricks to assemble into larger constructions. Compared with the first-generation bricks (which contained four binding domains, each composed of eight nucleotides), the longer binding domains of the DNA bricks provide better yields and stabilities for large assembled structures. The authors developed software called Nanobricks to design the brick strands needed to make target 3D objects, and used it to plan the synthesis of a set of different complex architectures (see Fig. 3 of the paper4).

Praetorius et al.5 […] report biotechnology that should greatly reduce the cost of the hundreds of staple strands that are usually used to make DNA origami. They use viruses known as bacteriophages to produce single-stranded precursor DNA that contains hundreds of staple-strand sequences. These sequences are separated by a ‘DNAzyme’ sequence that cleaves itself; the cleavage products then self-assemble into designated DNA origami shapes. Remarkably, the authors’ method reduces the cost of the folded DNA origami structures from about US$200 per milligram to around 20 cents. This strategy will enable scalable and efficient mass production of DNA origami and SST structures, thus enabling large-scale applications, such as therapeutics, drug-delivery systems and nanoelectronic devices.