Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Nanotechnology innovation may revolutionize gene detection in a single cell

14.01.2008
Scientists at Arizona State University’s Biodesign Institute have developed the world’s first gene detection platform made up entirely from self-assembled DNA nanostructures. The results, appearing in the January 11 issue of the journal Science, could have broad implications for gene chip technology and may also revolutionize the way in which gene expression is analyzed in a single cell.

“We are starting with the most well-known structure in biology, DNA, and applying it as a nano-scale building material, ” said Hao Yan, a member of the institute’s Center for Single Molecule Biophysics and an assistant professor of chemistry and biochemistry in the College of Liberal and Sciences.

Yan is a researcher in the fast-moving field known as structural DNA nanotechnology — that assembles the molecule of life into a variety of nanostructures with a broad range of applications from human health to nanoelectronics.

Yan led an interdisciplinary ASU team to develop a way to use structural DNA nanotechnology to target the chemical messengers of genes, called RNA.

... more about:
»DNA »Detection »Nanotechnology »RNA »Yan »nanoarray

The team included: lead author and chemistry and biochemistry graduate student Yonggang Ke; assistant professor of chemistry and biochemistry Yan Liu; Center for Single Molecule Biophysics director and physics professor Stuart Lindsay; and associate professor in the School of Life Sciences, Yung Chang.

"This is one of the first practical applications of a powerful technology, that, till now, has mainly been the subject of research demonstrations,” said Lindsay. “The field of structural DNA nanotechnology has recently seen much exciting progress from constructing geometrical and topological nanostructures through tile based DNA self-assembly initially demonstrated by Ned Seeman, Erik Winfree and colleagues,” said Yan.

A recent breakthrough of making spatially addressable DNA nanoarrays came from Paul Rothemund’s work on scaffolded DNA origami, a method in which a long, single-stranded viral DNA scaffold can be folded and stapled by a large number of short synthetic “helper strands” into nanostructures that display complex patterns.

“But the potential of structural DNA nanotechnology in biological applications has been underestimated, and if we look at the process of DNA self-assembly, you will be amazed that trillions of DNA nanostructures can form simultaneously in a solution of few microliters, and very importantly, they are biocompatible and water soluble,” said Yan.

DNA chip and microarray technology have become a multi-billion dollar industry as scientists use it to examine thousands of genes at the same time for mutations or uncovering clues to disease. However, because DNA probes are pinned to the solid surface of the microarray chips, it is relatively slow process for the targets to search and find the probes. Also, it is hard to control the distances between the probes with nanometer accuracy.

“In this work, we developed a water soluble nanoarray that can take advantage of the DNA self-assembling process and also have benefits that the macroscopic DNA microchip arrays do not have,” said Yan. “The arrays themselves are reagents, instead of solid surface chips.”

To make the DNA origami RNA probes, Yan has taken advantage of the basic DNA pairing rules in the DNA chemical alphabet (“A” can only form a zipper-like chemical bond with “T” and “G” only pair with “C”). By controlling the exact position and location of the chemical bases within a synthetic replica of DNA, Yan programmed a single stranded genomic DNA, M13, into nanotiles to contain the probes for specific gene expression targets.

Yan refers to the self-assembled DNA nanoarrays as nucleic acid probe tiles, which look like a nanosized postage stamp. In a single step, the M13 scaffold system can churn out as many as 100 trillion of the tiles with close to100 percent yield.

Yan’s team designed three different DNA probe tiles to detect three different RNA genes along with a bar code index to tell the tiles apart from each other. “Each probe can be distinguished by its own bar code, so we mixed them together in one solution and we used this for multiplex detection,” said Yan. The group uses a powerful instrument, atomic force microscopy (AFM), which allows the researchers to image the tiles at the single molecule level.

On the surface of each DNA probe tile is a dangling single stranded piece of DNA that can bind to the RNA target of interest. “Each probe actually contains two half probes, so when the target RNA comes in, it will hybridize to the half probes and turn the single stranded dangling probes into a stiff structure,” said Yan. “When it is stiffened, it will be sensed by the atomic force microscope cantilever, and you can see a bright line, which is a height increase. The result is a mechanical, label-free detection.”

The technology is able to detect minute quantities of RNA. “Since the DNA-RNA hybridization has such a strong affinity, in principle, a single molecule would be able to hybridize to the probe tile,” said Yan.

Although there are still many technical hurdles yet to overcome, the group is excited about the potential applications of the technology. “What our approach provides is that the probe tiles are a water-soluble reagent, so the sample volume can potentially be shrunk down to the volume of a single cell level. Our ultimate goal is to detect RNA gene expression at the single cell level.”

Joe Caspermeyer | EurekAlert!
Further information:
http://www.asu.edu

Further reports about: DNA Detection Nanotechnology RNA Yan nanoarray

More articles from Life Sciences:

nachricht Scientists unlock ability to generate new sensory hair cells
22.02.2017 | Brigham and Women's Hospital

nachricht New insights into the information processing of motor neurons
22.02.2017 | Max Planck Florida Institute for Neuroscience

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Microhotplates for a smart gas sensor

22.02.2017 | Power and Electrical Engineering

Scientists unlock ability to generate new sensory hair cells

22.02.2017 | Life Sciences

Prediction: More gas-giants will be found orbiting Sun-like stars

22.02.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>