Nanotechnology Now

Our NanoNews Digest Sponsors
Heifer International

Wikipedia Affiliate Button

Home > Press > Roomy cages built from DNA: Self-assembling cages are the largest standalone 3-D DNA structures yet, and could one day deliver drugs, or house tiny bioreactors or photonic devices

The five cage-shaped DNA polyhedra here have struts stabilizing their legs, and this innovation allowed a Wyss Institute team to build by far the largest and sturdiest DNA cages yet. The largest, a hexagonal prism (right), is one-tenth the size of an average bacterium.

Credit: Yonggang Ke/Harvard's Wyss Institute
The five cage-shaped DNA polyhedra here have struts stabilizing their legs, and this innovation allowed a Wyss Institute team to build by far the largest and sturdiest DNA cages yet. The largest, a hexagonal prism (right), is one-tenth the size of an average bacterium.

Credit: Yonggang Ke/Harvard's Wyss Institute

Abstract:
Move over, nanotechnologists, and make room for the biggest of the small. Scientists at the Harvard's Wyss Institute have built a set of self-assembling DNA cages one-tenth as wide as a bacterium. The structures are some of the largest and most complex structures ever constructed solely from DNA, they report today's online edition of Science.



To create supersharp images of their cage-shaped DNA polyhedra, the scientists used DNA-PAINT, a microscopy method that uses short strands of DNA (yellow) labeled with a fluorescent chemical (green) to bind and release partner strands on polyhedra corners, causing them to blink. The blinking corners reveal the shape of structures far too small to be seen with a conventional light microscope

Credit: Harvard's Wyss Institute and Harvard Medical School

Roomy cages built from DNA: Self-assembling cages are the largest standalone 3-D DNA structures yet, and could one day deliver drugs, or house tiny bioreactors or photonic devices

Cambridge, MA | Posted on March 13th, 2014

Moreover, the scientists visualized them using a DNA-based super-resolution microscopy method -- and obtained the first sharp 3D optical images of intact synthetic DNA nanostructures in solution.

In the future, scientists could potentially coat the DNA cages to enclose their contents, packaging drugs for delivery to tissues. And, like a roomy closet, the cage could be modified with chemical hooks that could be used to hang other components such as proteins or gold nanoparticles. This could help scientists build a variety of technologies, including tiny power plants, miniscule factories that produce specialty chemicals, or high-sensitivity photonic sensors that diagnose disease by detecting molecules produced by abnormal tissue.

"I see exciting possibilities for this technology," said Peng Yin, Ph.D., a Core Faculty member at the Wyss Institute and Assistant Professor of Systems Biology at Harvard Medical School, and senior author of the paper.

Building with DNA

DNA is best known as a keeper of genetic information. But scientists in the emerging field of DNA nanotechnology are exploring ways to use it to build tiny structures for a variety of applications. These structures are programmable, in that scientists can specify the sequence of letters, or bases, in the DNA, and those sequences then determine the structure it creates.

So far most researchers in the field have used a method called DNA origami, in which short strands of DNA staple two or three separate segments of a much longer strand together, causing that strand to fold into a precise shape. DNA origami was pioneered in part by Wyss Institute Core Faculty member William Shih, Ph.D., who is also an Associate Professor in the Department of Biological Chemistry and Molecular Pharmacology at Harvard Medical School and the Department of Cancer Biology at the Dana-Farber Cancer Institute.

Yin's team has built different types of DNA structures, including a modular set of parts called single-stranded DNA tiles or DNA bricks. Like LEGO® bricks, these parts can be added or removed independently. Unlike LEGO® bricks, they spontaneously self-assemble.

But for some applications, scientists might need to build much larger DNA structures than anyone has built so far. So, to add to their toolkit, Yin's team sought much larger building blocks to match.

Engineering challenges

Yin and his colleagues first used DNA origami to create extra-large building blocks the shape of a photographer's tripod. The plan was to engineer those tripod legs to attach end-to-end to form polyhedra -- objects with many flat faces that are themselves triangles, rectangles, or other polygons.

But when Yin and the paper's three lead authors, Ryosuke Iinuma, a former Wyss Institute Visiting Fellow, Yonggang Ke, Ph.D., a former Wyss Postdoctoral Fellow who is now an Assistant Professor of Biomedical Engineering at Georgia Institute of Technology and Emory University, and Ralf Jungman, Ph.D, a Wyss Postdoctoral Fellow, built bigger tripods and tried to assemble them into polyhedra, the large tripods' legs would splay and wobble, which kept them from making polyhedra at all.

The researchers got around that problem by building in a horizontal strut to stabilize each pair of legs, just as a furniture maker would use a piece of wood to bridge legs of a wobbly chair.

To glue the tripod legs together end-to-end, they took advantage of the fact that matching DNA strands pair up and adhere to each other. They left a tag of DNA hanging off a tripod leg, and a matching tag on the leg of a different tripod that they wanted it to pair with.

The team programmed DNA to fold into sturdy tripods 60 times larger than previous DNA tripod-like building blocks and 400 times larger than DNA bricks. Those tripods then self-assembled into a specific type of three-dimensional polyhedron -- all in a single test tube.

By adjusting the length of the strut, they built tripods that ranged from upright to splay-legged. More upright tripods formed polyhedra with fewer faces and sharper angles, such as a tetrahedron, which has four triangular faces. More splay-legged tripods formed polyhedra with more faces, such as a hexagonal prism, which is shaped like a wheel of cheese and has eight faces, including its top and bottom.

In all, they created five polyhedra: a tetrahedron, a triangular prism, a cube, a pentagonal prism, and a hexagonal prism.

Ultrasharp snapshots

After building the cages, the scientists visualized them using a DNA-based microscopy method Jungmann had helped developed called DNA-PAINT. In DNA-PAINT, short strands of modified DNA cause points on a structure to blink, and data from the blinking images reveal structures too small to be seen with a conventional light microscope. DNA-PAINT produced ultrasharp snapshots of the researchers' DNA cages - the first 3D snapshots ever of single DNA structures in their native, watery environment.

"Bioengineers interested in advancing the field of nanotechnology need to devise manufacturing methods that build sturdy components in a highly robust manner, and develop self-assembly methods that enable formation of nanoscale devices with defined structures and functions," said Wyss Institute Founding Director Don Ingber, M.D., Ph.D. "Peng's DNA cages and his methods for visualizing the process in solution represent major advances along this path."

###

This work was funded by the Office of Naval Research, the Army Research Office, the National Institutes of Health, the National Science Foundation, the JSR Corporation, and the Wyss Institute. In addition to Yin, Iinuma, Ke, and Jungmann, the research team included Thomas Schlichthaerle, a visiting student at the Wyss Institute, and Johannes B. Woehrstein, a research fellow at the Wyss Institute.

####

About Wyss Institute for Biologically Inspired Engineering at Harvard
The Wyss Institute for Biologically Inspired Engineering at Harvard University uses Nature's design principles to develop bioinspired materials and devices that will transform medicine and create a more sustainable world. Working as an alliance among all of Harvard's Schools, and in partnership with Beth Israel Deaconess Medical Center, Brigham and Women's Hospital, Boston Children's Hospital, Dana Farber Cancer Institute, Massachusetts General Hospital, the University of Massachusetts Medical School, Spaulding Rehabilitation Hospital, Boston University, Tufts University, and Charité - Universitätsmedizin Berlin, the Institute crosses disciplinary and institutional barriers to engage in high-risk research that leads to transformative technological breakthroughs. By emulating Nature's principles for self-organizing and self-regulating, Wyss researchers are developing innovative new engineering solutions for healthcare, energy, architecture, robotics, and manufacturing. These technologies are translated into commercial products and therapies through collaborations with clinical investigators, corporate alliances, and new start-ups.

For more information, please click here

Contacts:
Dan Ferber

617-432-1547

Copyright © Harvard University

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

Imaging

uSEE breakthrough unlocks the nanoscale world on standard biology lab equipment August 16th, 2019

Closing the terahertz gap: Tiny laser is an important step toward new sensors July 25th, 2019

Limitation exposed in promising quantum computing material: Metallic surfaces no longer protected as topological insulators become thinner July 19th, 2019

Caught in the act: Images capture molecular motions in real time July 15th, 2019

News and information

uSEE breakthrough unlocks the nanoscale world on standard biology lab equipment August 16th, 2019

Optofluidic chip with nanopore 'smart gate' developed for single molecule analysis: Programmable device enables on-demand delivery of individual biomolecules with feedback-controlled gating for high-throughput analysis August 16th, 2019

ULVAC Launches Revolutionary PZT Piezoelectric Thin-film Process Technology and HVM Solution for MEMS Sensors/Actuators: Enabling Reliable, High-quality Film Production for Next Generation Devices August 16th, 2019

RIT to upgrade Semiconductor and Microsystems Fabrication Laboratory through $1 million state grant: Upgrades to clean room will enhance university’s research capabilities in photonics, quantum technologies and smart systems August 16th, 2019

Videos/Movies

Researchers embrace imperfection to improve biomolecule transport August 8th, 2019

Govt.-Legislation/Regulation/Funding/Policy

uSEE breakthrough unlocks the nanoscale world on standard biology lab equipment August 16th, 2019

Optofluidic chip with nanopore 'smart gate' developed for single molecule analysis: Programmable device enables on-demand delivery of individual biomolecules with feedback-controlled gating for high-throughput analysis August 16th, 2019

Damaged hearts rewired with nanotube fibers: Texas Heart doctors confirm Rice-made, conductive carbon threads are electrical bridges August 14th, 2019

You're not so tough, h-BN: Rice University chemists find new path to make strong 2D material better for applications August 14th, 2019

Molecular Nanotechnology

DNA origami to scale-up molecular motors June 13th, 2019

Big energy savings for tiny machines May 24th, 2019

2D gold quantum dots are atomically tunable with nanotubes April 11th, 2019

The feature size and functional range of molecular electronic devices: Monitoring the transition from tunneling leakage current to molecular tunneling December 16th, 2018

Self Assembly

A new way of making complex structures in thin films: Self-assembling materials can form patterns that might be useful in optical devices July 5th, 2019

University of Konstanz researchers create uniform-shape polymer nanocrystals: Researchers from the University of Konstanz's CRC 1214 'Anisotropic Particles as Building Blocks: Tailoring Shape, Interactions and Structures' generate uniform-shape nanocrystals using direct polymeriz June 14th, 2019

DNA origami to scale-up molecular motors June 13th, 2019

Multistep self-assembly opens door to new reconfigurable materials April 19th, 2019

Discoveries

uSEE breakthrough unlocks the nanoscale world on standard biology lab equipment August 16th, 2019

Optofluidic chip with nanopore 'smart gate' developed for single molecule analysis: Programmable device enables on-demand delivery of individual biomolecules with feedback-controlled gating for high-throughput analysis August 16th, 2019

Probing the Origin of Alzheimer’s . . . with Transistors: Novel high-sensitivity detector could aid in early diagnosis August 15th, 2019

Damaged hearts rewired with nanotube fibers: Texas Heart doctors confirm Rice-made, conductive carbon threads are electrical bridges August 14th, 2019

Announcements

uSEE breakthrough unlocks the nanoscale world on standard biology lab equipment August 16th, 2019

Optofluidic chip with nanopore 'smart gate' developed for single molecule analysis: Programmable device enables on-demand delivery of individual biomolecules with feedback-controlled gating for high-throughput analysis August 16th, 2019

ULVAC Launches Revolutionary PZT Piezoelectric Thin-film Process Technology and HVM Solution for MEMS Sensors/Actuators: Enabling Reliable, High-quality Film Production for Next Generation Devices August 16th, 2019

RIT to upgrade Semiconductor and Microsystems Fabrication Laboratory through $1 million state grant: Upgrades to clean room will enhance university’s research capabilities in photonics, quantum technologies and smart systems August 16th, 2019

Interviews/Book Reviews/Essays/Reports/Podcasts/Journals/White papers

uSEE breakthrough unlocks the nanoscale world on standard biology lab equipment August 16th, 2019

Optofluidic chip with nanopore 'smart gate' developed for single molecule analysis: Programmable device enables on-demand delivery of individual biomolecules with feedback-controlled gating for high-throughput analysis August 16th, 2019

Probing the Origin of Alzheimer’s . . . with Transistors: Novel high-sensitivity detector could aid in early diagnosis August 15th, 2019

Damaged hearts rewired with nanotube fibers: Texas Heart doctors confirm Rice-made, conductive carbon threads are electrical bridges August 14th, 2019

Tools

uSEE breakthrough unlocks the nanoscale world on standard biology lab equipment August 16th, 2019

Cellulose nanofibers to improve the sensitivity of lateral flow tests August 7th, 2019

How to trick electrons to see the hidden face of crystals: Researchers try a trick for complete 3D analysis of submicron crystals August 3rd, 2019

Nanoscribe expands its worldwide presence: Specialist for 3D nano and micro fabrication opens US subsidiary for service and sales July 31st, 2019

Grants/Sponsored Research/Awards/Scholarships/Gifts/Contests/Honors/Records

Damaged hearts rewired with nanotube fibers: Texas Heart doctors confirm Rice-made, conductive carbon threads are electrical bridges August 14th, 2019

You're not so tough, h-BN: Rice University chemists find new path to make strong 2D material better for applications August 14th, 2019

Researchers embrace imperfection to improve biomolecule transport August 8th, 2019

RIT awarded NSF funding to conceptualize Quantum Photonic Institute: RIT will develop plan for open-access Quantum Foundry for quantum photonic circuits August 7th, 2019

Nanobiotechnology

uSEE breakthrough unlocks the nanoscale world on standard biology lab equipment August 16th, 2019

Probing the Origin of Alzheimer’s . . . with Transistors: Novel high-sensitivity detector could aid in early diagnosis August 15th, 2019

Damaged hearts rewired with nanotube fibers: Texas Heart doctors confirm Rice-made, conductive carbon threads are electrical bridges August 14th, 2019

Nanoparticles’ movement reveals whether they can successfully target cancer: Targeting nanoparticles rotate faster and move across larger areas August 9th, 2019

NanoNews-Digest
The latest news from around the world, FREE



  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project