PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

DNA motor 'walks' along nanotube, transports tiny particle

2013-12-18
(Press-News.org) Contact information: Emil Venere
venere@purdue.edu
765-494-4709
Purdue University
DNA motor 'walks' along nanotube, transports tiny particle

WEST LAFAYETTE, Ind. - Researchers have created a new type of molecular motor made of DNA and demonstrated its potential by using it to transport a nanoparticle along the length of a carbon nanotube.

The design was inspired by natural biological motors that have evolved to perform specific tasks critical to the function of cells, said Jong Hyun Choi, a Purdue University assistant professor of mechanical engineering.

Whereas biological motors are made of protein, researchers are trying to create synthetic motors based on DNA, the genetic materials in cells that consist of a sequence of four chemical bases: adenine, guanine, cytosine and thymine. The walking mechanism of the synthetic motors is far slower than the mobility of natural motors. However, the natural motors cannot be controlled, and they don't function outside their natural environment, whereas DNA-based motors are more stable and might be switched on and off, Choi said.

"We are in the very early stages of developing these kinds of synthetic molecular motors," he said.

New findings were detailed in a research paper published this month in the journal Nature Nanotechnology.

In coming decades, such molecular motors might find uses in drug delivery, manufacturing and chemical processing.

The new motor has a core and two arms made of DNA, one above and one below the core. As it moves along a carbon-nanotube track it continuously harvests energy from strands of RNA, molecules vital to a variety of roles in living cells and viruses.

The Nature Nanotechnology paper was authored by graduate students Tae-Gon Cha, Jing Pan and Haorong Chen; former undergraduate student Janette Salgado; graduate student Xiang Li; Chengde Mao, a professor of chemistry; and Choi.

"Our motors extract chemical energy from RNA molecules decorated on the nanotubes and use that energy to fuel autonomous walking along the carbon nanotube track," Choi said.

The core is made of an enzyme that cleaves off part of a strand of RNA. After cleavage, the upper DNA arm moves forward, binding with the next strand of RNA, and then the rest of the DNA follows. The process repeats until reaching the end of the nanotube track.

Researchers used the motor to move nanoparticles of cadmium disulfide along the length of a nanotube. The nanoparticle is about 4 nanometers in diameter.

The researchers combined two fluorescent imaging systems to document the motor's movement, one in the visible spectrum and the other in the near-infrared range. The nanoparticle is fluorescent in visible light and the nanotubes are fluorescent in the near-infrared.

The motor took about 20 hours to reach the end of the nanotube, which was several microns long, but the process might be sped up by changing temperature and pH, a measure of acidity.



INFORMATION:

This work has been supported by the U.S. Office of Naval Research.

Writer: Emil Venere, 765-494-4709, venere@purdue.edu

Source: Jong Hyun Choi, 765-496-3562, jchoi@purdue.edu

IMAGE CAPTION: This illustration depicts the walking mechanism of a new type of DNA motor that researchers have demonstrated by using it to transport a nanoparticle along the length of a carbon nanotube. (Purdue University image/Tae-Gon Cha)

A publication-quality image is available at http://news.uns.purdue.edu/images/2013/choi-dnamotor.jpg

ABSTRACT
A Synthetic DNA Motor that Transports Nanoparticles Along Carbon Nanotubes
Tae-Gon Cha1, Jing Pan1, Haorong Chen1, Janette Salgado1, Xiang Li2, Chengde Mao2 and Jong Hyun Choi1 *
1 School of Mechanical Engineering, Bindley Bioscience Center, Birck Nanotechnology Center, Purdue University
2 Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, USA. *e-mail: jchoi@purdue.edu
Intracellular protein motors have evolved to perform specific tasks critical to the function of cells such as intracellular trafficking and cell division. Kinesin and dynein motors, for example, transport cargos in living cells by walking along microtubules powered by adenosine triphosphate hydrolysis. These motors can make discrete 8 nm centre-of-mass steps and can travel over 1 micrometer by changing their conformations during the course of adenosine triphosphate binding, hydrolysis and product release. Inspired by such biological machines, synthetic analogues have been developed including self-assembled DNA walkers that can make stepwise movements on RNA/DNA substrates or can function as programmable assembly lines. Here, we show that motors based on RNA-cleaving DNA enzymes can transport nanoparticle cargoes (CdS nanocrystals in this case) along single-walled carbon nanotubes. Our motors extract chemical energy from RNA molecules decorated on the nanotubes and use that energy to fuel autonomous, processive walking through a series of conformational changes along the one-dimensional track. The walking is controllable and adapts to changes in the local environment, which allows us to remotely direct GO and STOP actions. The translocation of individual motors can be visualized in real time using the visible fluorescence of the cargo nanoparticle and the near-infrared emission of the carbon-nanotube track. We observed unidirectional movements of the molecular motors over 3 micrometers with a translocation velocity on the order of 1 nm per min under our experimental conditions.



ELSE PRESS RELEASES FROM THIS DATE:

CHOC researchers identify technique to reduce childrens' post-op pain after high-risk surgery

2013-12-18
CHOC researchers identify technique to reduce childrens' post-op pain after high-risk surgery Study shows encouraging results for improving postoperative pain management and reducing the need for pain medicine after major pediatric urology procedures Orange, Calif. ...

EGF receptor ecto-domain mutations: When to screen and when not to screen

2013-12-18
EGF receptor ecto-domain mutations: When to screen and when not to screen The epidermal growth factor receptor (EGFR) is expressed in normal colonic cells and is activated by specific peptide growth factors that regulate cell proliferation, survival and differentiation. ...

Hubble watches super star create holiday light show

2013-12-18
Hubble watches super star create holiday light show This festive NASA Hubble Space Telescope image resembles a holiday wreath made of sparkling lights. The bright southern hemisphere star RS Puppis, at the center of the image, is swaddled in a gossamer ...

World Health Organization study: Atrial fibrillation is a growing global health concern

2013-12-18
World Health Organization study: Atrial fibrillation is a growing global health concern LOS ANGELES (Dec. 17, 2013) – Atrial fibrillation, long considered the most common condition leading to an irregular heartbeat, is a growing and serious global health ...

Study: Moderate alcohol consumption boosts body's immune system

2013-12-18
Study: Moderate alcohol consumption boosts body's immune system PORTLAND, Ore. — Medical science has known for years that people who drink moderate amounts of alcohol actually have a reduced risk of death. In general, they are healthier and have better cardiovascular ...

Muscle-invasive and non-muscle invasive bladder cancers arise from different stem cells

2013-12-18
Muscle-invasive and non-muscle invasive bladder cancers arise from different stem cells 'Knowing the risk can help doctors and patients make informed treatment decisions,' researcher says Bladder cancer will kill upward of 170,000 people worldwide this year, ...

New hypertension guidelines offer practical, clinical information for doctors and patients around the globe

2013-12-18
New hypertension guidelines offer practical, clinical information for doctors and patients around the globe Presented by the American Society of Hypertension Inc. and the International Society of Hypertension High blood pressure affects approximately ...

Spiders partial to a side order of pollen with their flies

2013-12-18
Spiders partial to a side order of pollen with their flies Spiders may not be the pure predators we generally believe, after a study found that some make up a quarter of their diet by eating pollen. Dr Dirk Sanders of the University of Exeter demonstrated ...

Marijuana consumption in Washington state is higher than previously estimated, study finds

2013-12-18
Marijuana consumption in Washington state is higher than previously estimated, study finds Marijuana consumption in Washington state is about twice as large as previously estimated, according to a new RAND Corporation study. Using federal data and information from a new survey ...

Residents of poorer nations find greater meaning in life

2013-12-18
Residents of poorer nations find greater meaning in life While residents of wealthy nations tend to have greater life satisfaction, new research shows that those living in poorer nations report having greater meaning in life. These ...

LAST 30 PRESS RELEASES:

‘Molecular shield’ placed in the nose may soon treat common hay fever trigger

Beetles under climate stress lay larger male eggs: Wolbachia infection drives adaptive reproduction strategy in response to rising temperature and CO₂

Groundbreaking quantum study puts wave-particle duality to work

Weekly injection could be life changing for Parkinson’s patients

Toxic metals linked to impaired growth in infants in Guatemala

Being consistently physically active in adulthood linked to 30–40% lower risk of death

Nerve pain drug gabapentin linked to increased dementia, cognitive impairment risks

Children’s social care involvement common to nearly third of UK mums who died during perinatal period

‘Support, not judgement’: Study explores links between children’s social care involvement and maternal deaths

Ethnic minority and poorer children more likely to die in intensive care

Major progress in fertility preservation after treatment for cancer of the lymphatic system

Fewer complications after additional ultrasound in pregnant women who feel less fetal movement

Environmental impact of common pesticides seriously underestimated

The Milky Way could be teeming with more satellite galaxies than previously thought

New study reveals surprising reproductive secrets of a cricket-hunting parasitoid fly

Media Tip Sheet: Symposia at ESA2025

NSF CAREER Award will power UVA engineer’s research to improve drug purification

Tiny parasitoid flies show how early-life competition shapes adult success

New coating for glass promises energy-saving windows

Green spaces boost children’s cognitive skills and strengthen family well-being

Ancient trees dying faster than expected in Eastern Oregon

Study findings help hone precision of proven CVD risk tool

Most patients with advanced melanoma who received pre-surgical immunotherapy remain alive and disease free four years later

Introducing BioEmu: A generative AI Model that enables high-speed and accurate prediction of protein structural ensembles

Replacing mutated microglia with healthy microglia halts progression of genetic neurological disease in mice and humans

New research shows how tropical plants manage rival insect tenants by giving them separate ‘flats’

Condo-style living helps keep the peace inside these ant plants

Climate change action could dramatically limit rising UK heatwave deaths

Annual heat-related deaths projected to increase significantly due to climate and population change

Researchers discover new way cells protect themselves from damage

[Press-News.org] DNA motor 'walks' along nanotube, transports tiny particle