Keeping 'jumping genes' in check could help control some age-related diseases
Most organisms, including humans, have parasitic DNA fragments called "jumping genes" that insert themselves into DNA molecules, disrupting genetic instructions in the process. And that phenomenon can result in age-related diseases such as cancer.
But researchers at the University of Rochester now report that the "jumping genes" in mice become active as the mice age when a multi-function protein stops keeping them in check in order to take on another role.
In a study published today in Nature Communications, Professor of Biology Vera Gorbunova and Assistant Professor of Biology Andrei Seluanov explain that a protein called Sirt6 is needed to keep the jumping genes—technically known as retrotransposons—inactive. That's an entirely different function from the ones scientists had long associated with Sirt6, such as the repairing of broken DNA molecules and regulating metabolism.
"About half of the human genome is made up of retrotransposons," said Gorbunova. "By better understanding why these genomic parasites become active, we hope to better understand and perhaps delay the aging process in humans."
For the most part, retrotransposons remain silent and inactive in organisms' genomes. But once they do become active, these DNA fragments can duplicate themselves and "jump" to new areas of the genome, disrupting the function of another gene by landing in an important part of the gene and changing its DNA sequence information.
But what happens to the Sirt6 proteins that kept the jumping genes inactive in younger cells? The answer lies in the role that Sirt6 plays in repairing DNA damage. Cells accumulate a lot of DNA damage over time that needs to be constantly repaired. As cells get older, Sirt6 becomes busier in taking care of the DNA damage. Gorbunova and Seluanov hypothesized that Sirt6 becomes so preoccupied in repairing DNA damage in older cells that it is no longer available to keep the jumping genes inactive.
To test the theory, the team artificially caused DNA damage in young cells using gamma radiation or the chemical hydrogen peroxide. Once the damage took place, Sirt6 was immediately recruited to the damaged sites of the DNA to do its repair work.
Gorbunova and Seluanov found that the stressed cells—the ones with increased DNA damage—had a higher rate of "jumping gene" activity, when compared to the other cells. Then, when the amount of Sirt6 was artificially increased in the stressed cells, the retrotransposons did not become as readily active, keeping the genome safe.
"This suggests that supplying more Sirt6 protein might protect older cells from aging," said Gorbunova. "The idea would be to increase the Sirt6 pool so that enough proteins are available for both DNA repair and for keeping the retrotransposons inactive."
Peter Iglinski | Eurek Alert!
North and South Cooperation to Combat Tuberculosis
22.03.2018 | Universität Zürich
Researchers Discover New Anti-Cancer Protein
22.03.2018 | Universität Basel
An international team of researchers has discovered a new anti-cancer protein. The protein, called LHPP, prevents the uncontrolled proliferation of cancer cells in the liver. The researchers led by Prof. Michael N. Hall from the Biozentrum, University of Basel, report in “Nature” that LHPP can also serve as a biomarker for the diagnosis and prognosis of liver cancer.
The incidence of liver cancer, also known as hepatocellular carcinoma, is steadily increasing. In the last twenty years, the number of cases has almost doubled...
In just a few weeks from now, the Chinese space station Tiangong-1 will re-enter the Earth's atmosphere where it will to a large extent burn up. It is possible that some debris will reach the Earth's surface. Tiangong-1 is orbiting the Earth uncontrolled at a speed of approx. 29,000 km/h.Currently the prognosis relating to the time of impact currently lies within a window of several days. The scientists at Fraunhofer FHR have already been monitoring Tiangong-1 for a number of weeks with their TIRA system, one of the most powerful space observation radars in the world, with a view to supporting the German Space Situational Awareness Center and the ESA with their re-entry forecasts.
Following the loss of radio contact with Tiangong-1 in 2016 and due to the low orbital height, it is now inevitable that the Chinese space station will...
Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP, provider of research and development services for OLED lighting solutions, announces the founding of the “OLED Licht Forum” and presents latest OLED design and lighting solutions during light+building, from March 18th – 23rd, 2018 in Frankfurt a.M./Germany, at booth no. F91 in Hall 4.0.
They are united in their passion for OLED (organic light emitting diodes) lighting with all of its unique facets and application possibilities. Thus experts in...
A new scenario seeking to explain how Mars' putative oceans came and went over the last 4 billion years implies that the oceans formed several hundred million...
For the first time, an interdisciplinary team from the University of Basel has succeeded in integrating artificial organelles into the cells of live zebrafish embryos. This innovative approach using artificial organelles as cellular implants offers new potential in treating a range of diseases, as the authors report in an article published in Nature Communications.
In the cells of higher organisms, organelles such as the nucleus or mitochondria perform a range of complex functions necessary for life. In the networks of...
19.03.2018 | Event News
16.03.2018 | Event News
13.03.2018 | Event News
22.03.2018 | Trade Fair News
22.03.2018 | Earth Sciences
22.03.2018 | Earth Sciences