Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Enzyme shown to help protect genomic stability

18.02.2005


Findings may provide insights into aging and cancer

Genomes throughout the animal kingdom and beyond are characterized by extensive segments that are inactive, lengthy stretches of DNA containing multiple genes that are closed to gene transcription. Scientists believe one reason for this broad gene silencing is the vital need for genomic stability, for protection against unwanted recombinations of genetic material or other disruptions of the genome’s integrity.

Genomic instability, particularly in the regions at the ends of the chromosomes known as telomeres, has been linked to aging in humans and an elevated risk for aging-related diseases, the most prominent of which is cancer. For this reason, insights into the mechanisms of gene silencing could provide important guideposts for new approaches to retarding aging or treating cancer.



Now, an investigation led by researchers at The Wistar Institute has shown that an enzyme known as Ubp10 plays a vital role in protecting the telomeric regions of the genome from potential destabilizing molecular events. The enzyme helps to keep the genome structurally closed, unavailable for transcription and possibly protected from dangerous genetic recombinations with other regions of the genome. A report on the research, which was conducted in yeast, appears in the February 18 issue of Molecular Cell.

"There are regions of the genome that have to be inaccessible," says Shelley L. Berger, Ph.D., the Hilary Koprowski Professor in the gene expression and regulation program at Wistar and senior author on the study. "Otherwise, they can recombine with themselves or with other DNA segments. In the telomeres, such events may accelerate aging or trigger cancer in humans."

"We have identified a molecular mechanism to explain how this enzyme helps keep telomeric DNA silenced and potentially protects the genome from destabilizing activity," says N.C. Tolga Emre, a graduate student in Berger’s laboratory and lead author on the study.

The Ubp10 enzyme acts on histones, molecules that have attracted increasing attention from scientists as they move beyond sequencing the human genome to trying to better understand how DNA is managed and its activity regulated. Histones are small proteins around which DNA is coiled to create structures called nucleosomes. Compact strings of nucleosomes, then, form into chromatin, the substructure of chromosomes. In many cases, when the DNA is tightly wrapped around the histones, the genes cannot be accessed and their expression is repressed. When the coils of DNA around the histones are loosened or the histone molecules are altered, the genes become available for expression.

It is the complex activity governing this process to which Ubp10 contributes. Enzymatic modifications to histones control DNA activation or silencing through the addition or removal of acetyl, methyl, and ubiquitin molecules in prescribed sequences and patterns. One job of Ubp10, as identified in this study, is to remove ubiquitin from certain histones where ubiquitin is associated with gene activation and to maintain low levels of the ubiquitin molecule at those sites.

Interestingly, Ubp10 appears to work similarly and in concert with another enzyme called Sir2, which removes acetyl molecules from histones. Sir2 has also been associated with promoting genomic stability, and some studies have linked it intriguingly to the aging process. Some studies, for example, have suggested that low-calorie diets that extend life also boost Sir2 activity dramatically.

Franklin Hoke | EurekAlert!
Further information:
http://www.wistar.upenn.edu

More articles from Life Sciences:

nachricht What happens in the cell nucleus after fertilization
06.12.2016 | Helmholtz Zentrum München - Deutsches Forschungszentrum für Gesundheit und Umwelt

nachricht Researchers uncover protein-based “cancer signature”
05.12.2016 | Universität Basel

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

Simple processing technique could cut cost of organic PV and wearable electronics

06.12.2016 | Materials Sciences

3-D printed kidney phantoms aid nuclear medicine dosing calibration

06.12.2016 | Medical Engineering

Robot on demand: Mobile machining of aircraft components with high precision

06.12.2016 | Power and Electrical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>