Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

How Chromosome Ends Influence Cellular Aging

11.09.2013
Heidelberg researchers study the function of telomeres in cellular aging processes

By studying processes that occur at the ends of chromosomes, a team of Heidelberg researchers has unravelled an important mechanism towards a better understanding of cellular aging.

The scientists focused on the length of the chromosome ends, the so-called telomeres, which can be experimentally manipulated. Their research, which was conducted at the Center for Molecular Biology of Heidelberg University (ZMBH), allows for new approaches in the development of therapies for tissue loss and organ failure associated with senescence (cellular aging). The research results may also be significant for cancer treatment. They were recently published in the journal “Nature Structural & Molecular Biology”.

Each cell contains a set of chromosomes in which the vast majority of our genetic information is stored in the form of DNA. This information must be protected to ensure the proper functioning of the cell. To achieve this, the very ends of the chromosomes, the telomeres, play an important role in protecting the chromosomal DNA from being degraded. “We can imagine that telomeres are analogous to the plastic caps at the ends of our shoelaces. Without them, the ends of the laces get frayed and eventually the entire shoelace does not function properly,” explains Dr. Brian Luke. His research group at the ZMBH is primarily focused on understanding how telomeres protect DNA.

It is well known in the scientific community that telomeres shorten every time a cell divides and eventually become so short that they can no longer protect the chromosomes. The unprotected chromosome ends send signals that stop the cell from dividing further, a state referred to as “senescence”. Senescent cells occur more frequently as we age, which can contribute to tissue loss and organ failure. “In certain diseases, patients already have very short telomeres at birth and as a result they experience severe tissue loss and organ dysfunction at an early age”, says the Heidelberg scientist.

The research group headed by Dr. Luke has now discovered that turning transcription on or off at telomeres can have drastic effects on their length. Transcription is the process of making an RNA molecule from DNA. It has only recently been shown to occur at telomeres, but the functional significance of this discovery has remained a mystery. Molecular biologists Bettina Balk and André Maicher were now able to show that the RNA itself is the key regulator that drives telomere length changes, especially when it sticks to telomeric DNA to make a so-called “RNA-DNA hybrid molecule”.

“We experimentally changed the amount of RNA-DNA hybrids at the chromosome ends. We can thus either accelerate or diminish the rate of cellular senescence directly by affecting telomere length,” explains Bettina Balk. According to André Maicher, this could be a first step towards telomere-based therapies for tissue loss or organ failure. With respect to diseases, it remains to be determined whether altering transcription rates at telomeres does indeed improve health status. This approach is also significant for cancer cells, which do not senesce and are thus considered immortal. “Transcription-based telomere length control may therefore also be applicable to cancer treatment,” Dr. Luke emphasizes.

The junior research group of Dr. Luke is a member of the Network Aging Research (NAR) at Heidelberg University and receives funding by the Baden-Württemberg Stiftung. Further funding comes from the German Research Foundation in the framework of Heidelberg University’s Collaborative Research Centre “Cellular Surveillance and Damage Response” (SFB 1036).

Original publication:
B. Balk, A. Maicher, M. Dees, J. Klermund, S. Luke-Glaser, K. Bender & B. Luke: Telomeric RNA-DNA hybrids affect telomere length dynamics and senescence; Nat. Struct. Mol. Biol. (8 September 2013), DOI: 10.1038/nsmb.2662
Contact:
Dr. Brian Luke
Center for Molecular Biology of Heidelberg University
Phone +49 6221 54-6897, b.luke@zmbh.uni-heidelberg.de
Communications and Marketing
Press Office, phone +49 6221 54-2311
presse@rektorat.uni-heidelberg.de

Marietta Fuhrmann-Koch | idw
Further information:
http://www.uni-heidelberg.de

More articles from Life Sciences:

nachricht Bolstering fat cells offers potential new leukemia treatment
17.10.2017 | McMaster University

nachricht Ocean atmosphere rife with microbes
17.10.2017 | King Abdullah University of Science & Technology (KAUST)

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Ocean atmosphere rife with microbes

17.10.2017 | Life Sciences

Neutrons observe vitamin B6-dependent enzyme activity useful for drug development

17.10.2017 | Life Sciences

NASA finds newly formed tropical storm lan over open waters

17.10.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>