Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Nanoscale microscope sheds first light on gene repair

14.11.2006
Proteins called H2AX act as "first aid" to DNA, among other roles. For the first time, scientists using the world's most powerful light microscope (the only one of its kind in the Americas) have seen how H2AX is distributed in the cell nucleus: in clusters, directing the first aid/repair after DNA injuries to the region where it is really needed.

Many biological processes lie out of the visual reach of scientists. The benefits of high-resolution electron microscopy are often offset by disruptive sample preparation requirements. Light microscopy allows easier sample prep and observations of living cells, but it has limited resolution. By manipulating how light waves behave, however, biophysicists are expanding the limits of light microscopy, and one of the latest advances--the 4Pi microscope--provides never-before-seen views of cellular components, including structures within the nucleus.

In a paper published in the Proceedings of the National Academy of Sciences, Joerg Bewersdorf of the Institute for Molecular Biophysics at The Jackson Laboratory, with collaborators Brian Bennett of the UMass Medical School and Leica Microsystems and Kendall Knight of the UMass Medical School, used the 4Pi microscope to examine the cellular response to a type of severe damage to the genetic material, DNA double-strand breaks. Such breaks provoke a rapid and highly coordinated series of events to identify and repair the damage. The response is critical, and there is an increased risk for cancer, developmental abnormalities and immunological problems when components of the repair processes are defective.

Traditional microbiological and genetics techniques can shed light on the molecular pathways of repair, but they don't address the astonishingly complex three-dimensional structure of the genetic material in the nucleus. 4Pi microscopy allows researchers to actually see the response in three dimensions, at resolutions down to 100 nm. Therefore, the role of the physical structures in various processes within the nucleus can now be visualized.

... more about:
»4Pi »Bewersdorf »DNA »H2AX »Microscopy »Nucleus »clusters

"The general application of these methods will provide unprecedented insights into cellular molecular events," said Bewersdorf. "This study represents a significant advance in our ability to visualize and quantify nuclear proteins in 3D."

Bewersdorf, Bennett and Knight examined a protein called H2AX, a kind of histone. Histones are structural proteins that act as spools around which DNA is wound, and they can also play roles in gene regulation and gene repair. H2AX is an early responder to DNA damage, and its change to what is known as gamma-H2AX is important for the coordination of signaling and repair activities. But it had not been known how H2AX is distributed throughout the nucleus or why its conversion to gamma-H2AX is limited to within a short distance of a break site. By using selective staining techniques and 4Pi visualization, Bewersdorf and colleagues determined that H2AX is distributed in distinct clusters uniformly throughout the nucleus and that the structure of these clusters may determine the boundaries of where gamma-H2AX spreads in response to a break.

"The clusters may provide a platform for the immediate and robust response observed following DNA damage," said Bewersdorf. "Moving forward, we will analyze the localization of the H2AX clusters relative to other nuclear components."

Joyce Peterson | EurekAlert!
Further information:
http://www.jax.org

Further reports about: 4Pi Bewersdorf DNA H2AX Microscopy Nucleus clusters

More articles from Life Sciences:

nachricht Researchers identify potentially druggable mutant p53 proteins that promote cancer growth
09.12.2016 | Cold Spring Harbor Laboratory

nachricht Plant-based substance boosts eyelash growth
09.12.2016 | Fraunhofer-Institut für Angewandte Polymerforschung IAP

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Electron highway inside crystal

Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.

Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...

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...

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

Researchers identify potentially druggable mutant p53 proteins that promote cancer growth

09.12.2016 | Life Sciences

Scientists produce a new roadmap for guiding development & conservation in the Amazon

09.12.2016 | Ecology, The Environment and Conservation

Satellites, airport visibility readings shed light on troops' exposure to air pollution

09.12.2016 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>