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

News and information

Coal could yield treatment for traumatic injuries: Rice, Texas A&M, UTHealth scientists discover coal-derived ‘dots’ are effective antioxidant April 25th, 2019

Arrowhead Begins Triple Combination Cohort in Chronic HBV Patients and Earns $25 Million Milestone Payment from Janssen April 23rd, 2019

Micro-LEDs achieve superior brightness with Picosun’s ALD technology April 23rd, 2019

Scientists explore the unknown behaviour of gold nanoparticles with neutrons April 23rd, 2019

How slippery surfaces allow sticky pastes and gels to slide: Engineered surface treatment developed at MIT can reduce waste and improve efficiency in many processes April 23rd, 2019

Imaging

Scientists explore the unknown behaviour of gold nanoparticles with neutrons April 23rd, 2019

From 2D to 1D: Atomically quasi '1D' wires using a carbon nanotube template: New bulk synthesis method for nanowires of molybdenum telluride for nanoelectronics April 19th, 2019

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

2D borophene gets a closer look: Rice, Northwestern find new ways to image, characterize unique material April 11th, 2019

Videos/Movies

New microscopy method provides more details about nanocomposites April 12th, 2019

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

Govt.-Legislation/Regulation/Funding/Policy

Coal could yield treatment for traumatic injuries: Rice, Texas A&M, UTHealth scientists discover coal-derived ‘dots’ are effective antioxidant April 25th, 2019

Scientists explore the unknown behaviour of gold nanoparticles with neutrons April 23rd, 2019

Coincidence helps with quantum measurements: New method enables quantum simulations on larger systems April 22nd, 2019

From nata de coco to computer screens: Cellulose gets a chance to shine: Researchers at Osaka University meticulously measured the optical birefringence of highly aligned cellulose nanofibers, paving the way for sharper television, computer, and smartphone screens April 19th, 2019

Molecular Nanotechnology

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

Insights into magnetic bacteria may guide research into medical nanorobots December 12th, 2018

How to mass produce cell-sized robots: Technique from MIT could lead to tiny, self-powered devices for environmental, industrial, or medical monitoring October 24th, 2018

Self Assembly

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

Can a flowing liquid-like material maintain its structural order like crystals? February 27th, 2019

Self-assembling nanomaterial offers pathway to more efficient, affordable harnessing of solar power: The new materials produce a singlet fission reaction that creates more and extends the life of harvestable electronic charges January 24th, 2019

Light up logic: Engineers from UTokyo and RIKEN perform computational logic with light January 18th, 2019

Discoveries

Coal could yield treatment for traumatic injuries: Rice, Texas A&M, UTHealth scientists discover coal-derived ‘dots’ are effective antioxidant April 25th, 2019

Scientists explore the unknown behaviour of gold nanoparticles with neutrons April 23rd, 2019

How slippery surfaces allow sticky pastes and gels to slide: Engineered surface treatment developed at MIT can reduce waste and improve efficiency in many processes April 23rd, 2019

Coincidence helps with quantum measurements: New method enables quantum simulations on larger systems April 22nd, 2019

Announcements

Coal could yield treatment for traumatic injuries: Rice, Texas A&M, UTHealth scientists discover coal-derived ‘dots’ are effective antioxidant April 25th, 2019

Arrowhead Begins Triple Combination Cohort in Chronic HBV Patients and Earns $25 Million Milestone Payment from Janssen April 23rd, 2019

Micro-LEDs achieve superior brightness with Picosun’s ALD technology April 23rd, 2019

Scientists explore the unknown behaviour of gold nanoparticles with neutrons April 23rd, 2019

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

Coal could yield treatment for traumatic injuries: Rice, Texas A&M, UTHealth scientists discover coal-derived ‘dots’ are effective antioxidant April 25th, 2019

Scientists explore the unknown behaviour of gold nanoparticles with neutrons April 23rd, 2019

How slippery surfaces allow sticky pastes and gels to slide: Engineered surface treatment developed at MIT can reduce waste and improve efficiency in many processes April 23rd, 2019

Coincidence helps with quantum measurements: New method enables quantum simulations on larger systems April 22nd, 2019

Tools

Micro-LEDs achieve superior brightness with Picosun’s ALD technology April 23rd, 2019

New microscopy method provides more details about nanocomposites April 12th, 2019

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

Nanometrics to Announce First Quarter Financial Results on April 30, 2019 April 10th, 2019

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

Coal could yield treatment for traumatic injuries: Rice, Texas A&M, UTHealth scientists discover coal-derived ‘dots’ are effective antioxidant April 25th, 2019

From 2D to 1D: Atomically quasi '1D' wires using a carbon nanotube template: New bulk synthesis method for nanowires of molybdenum telluride for nanoelectronics April 19th, 2019

'Nanobodies' from alpacas could help bring CAR T-cell therapy to solid tumors: Unusually small antibodies, targeted to the tumor micro-environment, curb melanoma and colon cancer in mouse models April 11th, 2019

2D borophene gets a closer look: Rice, Northwestern find new ways to image, characterize unique material April 11th, 2019

Nanobiotechnology

Coal could yield treatment for traumatic injuries: Rice, Texas A&M, UTHealth scientists discover coal-derived ‘dots’ are effective antioxidant April 25th, 2019

Arrowhead Begins Triple Combination Cohort in Chronic HBV Patients and Earns $25 Million Milestone Payment from Janssen April 23rd, 2019

A light-activated remote control for cells April 17th, 2019

Arrowhead Pharmaceuticals Receives FDA Clearance to Begin Phase 2/3 Study of ARO-AAT for Treatment of Alpha-1 Liver Disease April 15th, 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