Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Scientists find missing link between players in the epigenetic code

01.10.2012
Over the last two decades, scientists have come to understand that the genetic code held within DNA represents only part of the blueprint of life. The rest comes from specific patterns of chemical tags that overlay the DNA structure, determining how tightly the DNA is packaged and how accessible certain genes are to be switched on or off.

As researchers have uncovered more and more of these "epigenetic" tags, they have begun to wonder how they are all connected. Now, research from the University of North Carolina School of Medicine has established the first link between the two most fundamental epigenetic tags -- histone modification and DNA methylation -- in humans.


Mouse embryonic stem cells (blue, green) lose DNA methylation (red) in the absence of UHRF1.

Credit: Strahl Lab, UNC School of Medicine

The study, which was published Sept. 30, 2012 by the journal Nature Structural & Molecular Biology, implicates a protein called UHRF1 in the maintenance of these epigenetic tags. Because the protein has been found to be defective in cancer, the finding could help scientists understand not only how microscopic chemical changes can ultimately affect the epigenetic landscape but also give clues to the underlying causes of disease and cancer.

"There's always been the suspicion that regions marked by DNA methylation might be connected to other epigenetic tags like histone modifications, and that has even been shown to be true in model organisms like fungus and plants," said senior study author Brian Strahl, PhD, associate professor of biochemistry and biophysics in the UNC School of Medicine and a member of UNC Lineberger Comprehensive Cancer Center. "But no one has been able to make that leap in human cells. It's been controversial in terms of whether or not there's really a connection. We have shown there is."

Strahl, along with his postdoctoral fellow Scott Rothbart, honed in on this discovery by using a highly sophisticated technique developed in his lab known as next generation peptide arrays. First the Strahl lab generated specific types of histone modifications and dotted them on tiny glass slides called "arrays." They then used these "arrays" to see how histone modifications affected the docking of different proteins. One protein – UHRF1 – stood out because it bound a specific histone modification (lysine 9 methylation on histone H3) in cases where others could not.

Strahl and his colleagues focused the rest of their experiments on understanding the role of UHRF1 binding to this histone modification. They found that while other proteins that dock on this epigenetic tag are ejected during a specific phase of the cell cycle, mitosis, UHRF1 sticks around. Importantly, the protein's association with histones throughout the cell cycle appears to be critical to maintaining another epigenetic tag called DNA methylation. The result was surprising because researchers had previously believed that the maintenance of DNA methylation occurred exclusively during a single step of the cell cycle called DNA replication.

"This role of UHRF1 outside of DNA replication is certainly unexpected, but I think it is just another way of making sure we don't lose information about our epigenetic landscape," said Strahl.

The research was funded by the National Institutes of Health and the North Carolina Biotechnology Center.

Study co-authors from UNC were Scott B. Rothbart, PhD, a postdoc in Strahl's lab at UNC; Krzysztof Krajewski, PhD, research assistant professor; and Jorge Y. Martinez, a former student in Strahl's lab.

Tom Hughes | EurekAlert!
Further information:
http://www.unch.unc.edu

Further reports about: DNA DNA methylation Medicine UHRF1 UNC cell cycle genetic tag histone modifications human cell

More articles from Life Sciences:

nachricht Antimicrobial substances identified in Komodo dragon blood
23.02.2017 | American Chemical Society

nachricht New Mechanisms of Gene Inactivation may prevent Aging and Cancer
23.02.2017 | Leibniz-Institut für Alternsforschung - Fritz-Lipmann-Institut e.V. (FLI)

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

From rocks in Colorado, evidence of a 'chaotic solar system'

23.02.2017 | Physics and Astronomy

'Quartz' crystals at the Earth's core power its magnetic field

23.02.2017 | Earth Sciences

Antimicrobial substances identified in Komodo dragon blood

23.02.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>