Figure 1. Assembly of four guanine (G) nucleobases into a quadruplex. The potassium ion in the center stabilizes the structure by bonding to the oxygen atoms on each guanine.
Figure 2. Chemical structures of DNA, RNA and PNA.
A team of investigators at Carnegie Mellon University has formed the first hybrid quadruplex of peptide nucleic acids, or PNAs, with DNA, the genetic code. This result opens new opportunities to study the activity of genetic regions occupied by recently described quadruplex DNA structures, as well as providing a new compound that could be used as a biosensor or to block gene activity associated with diseases such as cancer. The research results, published online, will appear in a forthcoming issue of the Journal of the American Chemical Society.
"PNA2-DNA2 hybrid quadruplexes are extremely stable, suggesting that if we use PNAs to bind with DNA quadruplexes that regulate gene expression, we could prevent disease processes in which these DNA quadruplexes appear to play a role," says Bruce Armitage, Ph.D., associate professor of chemistry at Carnegie Mellon. "PNAs also could be converted into biosensors by coupling them with fluorescent tags that would allow the PNA to report the presence of a successful hybridization to quadruplex-forming sequences either in the genome or in messenger RNA molecules."
"In addition to a new high-affinity DNA recognition mechanism and expanding the scope of molecular recognition by PNA, the PNA2-DNA2 hybrid quadruplex is the first example of homologous hybridization," adds Armitage.
Lauren Ward | EurekAlert!
Researchers reveal new details on aged brain, Alzheimer's and dementia
21.11.2017 | Allen Institute
Nanoparticles help with malaria diagnosis – new rapid test in development
21.11.2017 | Fraunhofer-Institut für Silicatforschung ISC
The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.
Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....
The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.
Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...
Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.
That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...
Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.
During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....
The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.
Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...
15.11.2017 | Event News
15.11.2017 | Event News
30.10.2017 | Event News
21.11.2017 | Physics and Astronomy
21.11.2017 | Materials Sciences
21.11.2017 | Health and Medicine