NIST publishes a beginner’s guide to origami DNA

In what is known as origami DNA, researchers repeatedly fold long strands of DNA to build a number of tiny 3D structures, including small biosensors and drug delivery vessels. Launched at the California Institute of Technology in 2006, origami DNA has attracted hundreds of new researchers over the past decade, seeking to build receptors and sensors that can detect and treat disease. in the human body, assessing the environmental impact of pollutants, and assisting with several other biological applications.

Although the principles of origami DNA are simple, the tools and methods of the technology for designing new structures are not easy to grasp and have not been well documented. Moreover, scientists new to the way they could turn to the most effective way to build DNA structures and how they can avoid obstacles that could last months did not have one specific reference. or even avoid years of study.

That’s why Jacob Majikes and Alex Liddle, researchers at the National Institute of Standards and Technology (NIST) who have studied origami DNA for years, have the first detailed tutorial on how to formulate it. Their comprehensive report provides step-by-step guidance on the design of DNA origami nanostructures, using state-of-the-art tools. Majikes and Liddle described their work in Jan .8 issue of the Journal of the National Institute of Standards and Technology study.

“We wanted to bring the tools that people have developed and put them in one place, and explain things that you can’t say in a traditional magazine article,” Majikes said. “Review papers may tell you everything that everyone did, but they don’t tell you how the people did it.”

DNA origami is dependent on the ability of integral base pairs of DNA molecules to bind together. Among the four bases of DNA – adenine (A), cytosine (C), guanine (G) and thymine (T) – A binds T and G with C. This means that a specific sequence of As, Ts, Cs and Gs find and connect to its fullness.

The bond allows short strands of DNA to become “staples,” holding sections of long strands folded or joined by individual strands. A typical origami design may require 250 staples. In this way, the DNA can self-assemble into different shapes, creating a nanoscale framework to which a combination of nanoparticles – many of which are useful in medical treatment, biological analysis and environmental analysis – can bind.

The challenges in using origami DNA are twofold, Majikes said. First, researchers are making 3D structures using a foreign language – the basic pairs A, G, T and C. In addition, they use these basic pair staples to make the helix double complex of twisting DNA molecules and to avoid them strands bend into specific shapes. That can be difficult to plan and see. Majikes and Liddle urge researchers to strengthen their design understanding by constructing 3D mock-ups, such as sculptures made with bar magnets, before they start making them. These models, which can tell which parts of the complex process are necessary and which are less important, should then be “smooth” to 2D to be compatible with computer-aided design tools. for origami DNA, which typically uses two-dimensional representations.

DNA folding can be accomplished in a number of ways, some not as effective as others, Majikes noted. Some strategies can, of course, be prone to failure.

“Identifying things like‘ You could do this, but it’s not a good idea ’- that kind of view is not in a traditional magazine article, but because NIST aims to leading the state of technology in the country, we are able to publish this work in the journal NIST, “Majikes said. “I don’t think there’s anywhere else that would give us the opportunity and the time and hours that this person has to put together.”

Liddle and Majikes plan to follow their work with several additional manuscripts explaining how to successfully make nanoscale devices with DNA.

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