Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Scientists tie DNA repair to key cell signaling network

18.06.2012
Previously unknown repair byproduct could be ‘master regulator’ of many basic cell processes

University of Texas Medical Branch at Galveston researchers have found a surprising connection between a key DNA-repair process and a cellular signaling network linked to aging, heart disease, cancer and other chronic conditions. The discovery promises to open up an important new area of research — one that could ultimately yield novel treatments for a wide variety of diseases.

"This is a totally new concept — it goes against current dogma about the role of DNA repair," said UTMB professor Istvan Boldogh, senior author of a paper on the work now online in the Journal of Biological Chemistry. "We couldn't believe it ourselves, but the data convinced us."

Boldogh and his colleagues came up with the idea of a link between DNA repair and cellular signaling after a close examination of the relationship between DNA damage and cell death produced unexpected results. Conventional DNA-repair dogma holds that a cell's lifespan is determined by the amount of accumulated DNA damage it suffers — the overall corruption of genetic information stored in sequences of molecules called bases, which form the "rungs" of the DNA double helix. The cells used in Boldogh's study were especially vulnerable to damage because they lacked a key enzyme that repairs the DNA base guanine. According to dogma, this should have shortened the cells' lives; instead, they actually lived longer than expected. This made Boldogh wonder if another factor was involved in reducing the lifespan of normal cells.

"We proposed the hypothesis that instead of the accumulation of damaged guanine in DNA causing ill effects, what is significant is the release of a DNA-repair byproduct that somehow activates processes that shorten the lifespan of cells," Boldogh said.

The researchers knew just where to look to find this hypothetical repair byproduct. The majority of DNA damage is caused by ubiquitous reactive oxygen species, very chemically active molecules created as byproducts of respiration. When DNA meets reactive oxygen species, one of the most common results is the transformation of the DNA base guanine into a molecule called 8-oxoguanine, which can produce mutations in genes.

To protect the integrity of the genetic code, cells remove 8-oxoguanine from their DNA with a repair enzyme called OGG1. OGG1 does its job by attaching to a damaged base, cutting it free from the DNA molecule, and then releasing it. Boldogh and his collaborators found that their key byproduct was being produced just after this repair process was completed. Analyzing test-tube, cell-culture and mouse experimental data, they realized that immediately after being released by OGG1, 8-oxoguanine reunites with the repair enzyme, attaching at a bonding site different from the one used previously. And the resulting 8-oxoguanine-OGG1 complex, they found, has the ability to activate the powerful Ras signaling pathways, some of the most important biochemical networks in the cell.

"Ras family proteins are involved in almost every cell function: metabolism, activation of genes, growth signals, inflammation signals, apoptosis," Boldogh said. "Because it activates Ras pathways, the release of 8-oxoguanine in DNA base repair could be a master regulator of many very basic processes."

According to Boldogh, learning to control this "master regulator," could result in profound consequences for biomedical science and human health. "The ability to regulate 8-oxoguanine excision may give us the ability to prevent the inflammation that's key to a number of chronic diseases — arthritis, atherosclerosis, Alzheimer's and others," he said. "We believe it may even enable us to extend lifespan, or at least healthy lifespan, which would be a very big achievement. Possibilities like that make us believe that this discovery is going to be very significant."

Other authors of the Journal of Biological Chemistry article include research associate Gyorgy Hajas, postdoctoral fellows Leopoldo Aguilera-Aguirre and Attila Bacsi, research scientist Muralidhar Hegde, associate professor Tapas Hazra, professors Sanjiv Sur and Sankar Mitra, Attila Bacsi of the University of Debrecen, Debrecen, Hungary, and Zsolt Radak of Semmelweis University, Budapest, Hungary. This research was supported by the National Institute of Environmental Health Sciences, the National Institute of Allergy and Infectious Disease and UTMB's National Heart Lung and Blood Institute Proteomics Center.

Jim Kelly | EurekAlert!
Further information:
http://www.utmb.edu

More articles from Life Sciences:

nachricht The hidden structure of the periodic system
17.06.2019 | Max-Planck-Institut für Mathematik in den Naturwissenschaften (MPIMIS)

nachricht Tiny probe that senses deep in the lung set to shed light on disease
17.06.2019 | University of Edinburgh

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: The hidden structure of the periodic system

The well-known representation of chemical elements is just one example of how objects can be arranged and classified

The periodic table of elements that most chemistry books depict is only one special case. This tabular overview of the chemical elements, which goes back to...

Im Focus: MPSD team discovers light-induced ferroelectricity in strontium titanate

Light can be used not only to measure materials’ properties, but also to change them. Especially interesting are those cases in which the function of a material can be modified, such as its ability to conduct electricity or to store information in its magnetic state. A team led by Andrea Cavalleri from the Max Planck Institute for the Structure and Dynamics of Matter in Hamburg used terahertz frequency light pulses to transform a non-ferroelectric material into a ferroelectric one.

Ferroelectricity is a state in which the constituent lattice “looks” in one specific direction, forming a macroscopic electrical polarisation. The ability to...

Im Focus: Determining the Earth’s gravity field more accurately than ever before

Researchers at TU Graz calculate the most accurate gravity field determination of the Earth using 1.16 billion satellite measurements. This yields valuable knowledge for climate research.

The Earth’s gravity fluctuates from place to place. Geodesists use this phenomenon to observe geodynamic and climatological processes. Using...

Im Focus: Tube anemone has the largest animal mitochondrial genome ever sequenced

Discovery by Brazilian and US researchers could change the classification of two species, which appear more akin to jellyfish than was thought.

The tube anemone Isarachnanthus nocturnus is only 15 cm long but has the largest mitochondrial genome of any animal sequenced to date, with 80,923 base pairs....

Im Focus: Tiny light box opens new doors into the nanoworld

Researchers at Chalmers University of Technology, Sweden, have discovered a completely new way of capturing, amplifying and linking light to matter at the nanolevel. Using a tiny box, built from stacked atomically thin material, they have succeeded in creating a type of feedback loop in which light and matter become one. The discovery, which was recently published in Nature Nanotechnology, opens up new possibilities in the world of nanophotonics.

Photonics is concerned with various means of using light. Fibre-optic communication is an example of photonics, as is the technology behind photodetectors and...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

SEMANTiCS 2019 brings together industry leaders and data scientists in Karlsruhe

29.04.2019 | Event News

Revered mathematicians and computer scientists converge with 200 young researchers in Heidelberg!

17.04.2019 | Event News

First dust conference in the Central Asian part of the earth’s dust belt

15.04.2019 | Event News

 
Latest News

Novel communications architecture for future ultra-high speed wireless networks

17.06.2019 | Information Technology

Climate Change in West Africa

17.06.2019 | Earth Sciences

Robotic fish to replace animal testing

17.06.2019 | Ecology, The Environment and Conservation

VideoLinks
Science & Research
Overview of more VideoLinks >>>