Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Nano-origami

12.02.2004


Scientists at Scripps research create single, clonable strand of DNA that folds into an octahedron



A group of scientists at The Scripps Research Institute has designed, constructed, and imaged a single strand of DNA that spontaneously folds into a highly rigid, nanoscale octahedron that is several million times smaller than the length of a standard ruler and about the size of several other common biological structures, such as a small virus or a cellular ribosome.

Making the octahedron from a single strand was a breakthrough. Because of this, the structure can be amplified with the standard tools of molecular biology and can easily be cloned, replicated, amplified, evolved, and adapted for various applications. This process also has the potential to be scaled up so that large amounts of uniform DNA nanomaterials can be produced. These octahedra are potential building blocks for future projects, from new tools for basic biomedical science to the tiny computers of tomorrow.


"Now we have biological control, and not just synthetic chemical control, over the production of rigid, wireframe DNA objects," says Research Associate William Shih, Ph.D., of Scripps Research.

Shih led the research, described in the latest issue of the journal Nature, with Professor Gerald Joyce, M.D., Ph.D., of the Department of Molecular Biology and The Skaggs Institute for Chemical Biology at Scripps Research.

Compartments and Scaffolds on the Nano-Scale

Similar to a piece of paper folded into an origami box, the strand of DNA that Shih and Joyce designed folds into a compact octahedron -- a structure consisting of twelve edges, six vertices, and eight triangular faces. The structure is about 22 nanometers in overall diameter.

These miniscule octahedral structures are the culmination of a design process that started one day when Shih was building a number of shapes with flexible ball and stick models in the laboratory. This exercise attracted his attention to an important structural principle: frames built with triangular faces are rigid, while cubes and other frames built with non-triangular faces are easily deformed.

Translating this principle to a scale over a million times smaller, Shih sought to design a DNA sequence that would fold into a triangle-faced, and therefore very rigid, object. Shih and Joyce settled on trying to build an octahedron.

Shih and Joyce constructed a 1669-nucleotide strand of DNA that they designed to have a number of self-complementary regions, which would induce the strand to fold back on itself to form a sturdy octahedron. Folding the DNA into the octahedral structures simply required the heating and then cooling of solutions containing the DNA, magnesium ions, and a few accessory molecules. And, indeed, the DNA spontaneously folded into the target structure.

The researchers used cryoelectron microscopy, in collaboration with Research Assistant Joel Quispe of the Scripps Research Automated Molecular Imaging Group, to take two-dimensional snapshots of the octahedral structures. Significantly, the structures were highly uniform in shape -- uniform enough, in fact, to allow the reconstruction of the three-dimensional structure by computational averaging of the individual particle images.

Potential Applications

Shih and Joyce note that because all twelve edges of the octahedral structures have unique sequences, they are versatile molecular building blocks that could potentially be used to self-assemble complex higher-order structures.

Possible applications include using these octahedra as artificial compartments into which proteins or other molecules could be inserted -- something Joyce likens to a virus in reverse, since in nature, viruses are self-assembling nanostructures that typically have proteins on the outside and DNA or RNA on the inside.

"With this," says Joyce, "you could in principle have DNA on the outside and proteins on the inside."

The DNA octahedra could possibly form scaffolds that host proteins for the purposes of x-ray crystallography, which depends on growing well-ordered crystals composed of arrays of molecules.

Another potential application is in the area of electronics and computing. Computers, which rely on the movement and storage of charges, can potentially be built with nano-scale transistors, but one of the big challenges to accomplishing this is organizing these components into integrated circuits. Structures like the ones that Shih and Joyce have developed might someday guide the assembly of nanoscale circuits that extend computing performance beyond the limits set by silicon integrated circuit technology.



The article, "A 1.7-kilobase single-stranded DNA that folds into a nanoscale octahedron" was authored by William M. Shih, Joel D. Quispe, and Gerald F. Joyce and appears in the February 12, 2004 issue of the journal Nature.

This work was supported by the National Aeronautics and Space Administration, The Skaggs Institute for Research, the National Institutes of Health through the National Center for Research Resources, and through a Damon Runyon Cancer Research Foundation fellowship.

About The Scripps Research Institute

The Scripps Research Institute in La Jolla, California, is one of the world’s largest, private, non-profit biomedical research organizations. It stands at the forefront of basic biomedical science that seeks to comprehend the most fundamental processes of life. Scripps Research is internationally recognized for its research into immunology, molecular and cellular biology, chemistry, neurosciences, autoimmune diseases, cardiovascular diseases and synthetic vaccine development.

Keith McKeown | EurekAlert
Further information:
http://www.scripps.edu/

More articles from Life Sciences:

nachricht A new technique isolates neuronal activity during memory consolidation
22.06.2017 | Spanish National Research Council (CSIC)

nachricht CWRU researchers find a chemical solution to shrink digital data storage
22.06.2017 | Case Western Reserve University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

Im Focus: Optoelectronic Inline Measurement – Accurate to the Nanometer

Germany counts high-precision manufacturing processes among its advantages as a location. It’s not just the aerospace and automotive industries that require almost waste-free, high-precision manufacturing to provide an efficient way of testing the shape and orientation tolerances of products. Since current inline measurement technology not yet provides the required accuracy, the Fraunhofer Institute for Laser Technology ILT is collaborating with four renowned industry partners in the INSPIRE project to develop inline sensors with a new accuracy class. Funded by the German Federal Ministry of Education and Research (BMBF), the project is scheduled to run until the end of 2019.

New Manufacturing Technologies for New Products

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

A new technique isolates neuronal activity during memory consolidation

22.06.2017 | Life Sciences

Plant inspiration could lead to flexible electronics

22.06.2017 | Materials Sciences

A rhodium-based catalyst for making organosilicon using less precious metal

22.06.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>