Epigenetic regulation – modifications to the structure of chromatin that influence which genes are expressed in a cell – is a key player in embryonic development and cancer formation. Researchers at the European Molecular Biology Laboratory [EMBL] in Heidelberg now gained new insight into one crucial epigenetic mechanism and reveal that it acts much faster than assumed.
In this week's issue of Nature they report that estrogen causes rapid epigenetic changes in breast cancer cells. The new findings impact upon our understanding of how cells interpret their DNA and suggest that epigenetic regulation can affect gene expression immediately and long-term.
Epigenetic changes to the structure of chromatin – tightly packaged DNA - grant or deny access to the molecular machinery that transcribes DNA and thereby regulate gene expression. One of these mechanisms is DNA methylation, where a small chemical residue called a methyl group is added to strategic bases on the DNA. The methyl group prevents the transcription machinery from docking and thereby shuts down gene expression. For a long time scientists have considered methylation a mechanism of long-term regulation of a gene's activity, because the methylation marks are stable and maintained through cellular replication.
EMBL researchers of the group of Frank Gannon, current director of the Science Foundation Ireland, now found out that methylation marks occur rapidly in breast cancer cells in response to hormones such as estrogen or drug compounds. Estrogen withdrawal or treatment with the established anticancer drug doxorubicin cause the methyl groups to be removed from regulatory regions of specific genes within tens of minutes in human breast cancer cells. The treatment sets off a whole cycle of events: initial demethylation renders silent genes active and subsequent remethylation shuts them down again. This cycle repeats itself every 1.5 hours.
"We observed that unlike assumed for a long time methylation can act on a very short timescale. The results challenge our understanding of epigenetics as a means to regulate gene expression permanently," says Sara Kangaspeska, who carried out the research together with Brenda Stride.
The new insights into the cyclical nature of methylation might shed light on the molecular bases of cancer and development, both processes involving epigenetic mechanisms.
"In particular breast cancer is affected by estrogen signalling and changes in epigenetic control," says George Reid, co-senior author of the study. "Our next step will be to find small molecules that target the cyclical methylation processes to elucidate their precise role."
Published in Nature on 6 March 2008.
Anna-Lynn Wegener | EMBL
Russian scientists show changes in the erythrocyte nanostructure under stress
22.02.2019 | Lobachevsky University
How the intestinal fungus Candida albicans shapes our immune system
22.02.2019 | Exzellenzcluster Präzisionsmedizin für chronische Entzündungserkrankungen
An international research team including astronomers from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has combined radio telescopes from five continents to prove the existence of a narrow stream of material, a so-called jet, emerging from the only gravitational wave event involving two neutron stars observed so far. With its high sensitivity and excellent performance, the 100-m radio telescope in Effelsberg played an important role in the observations.
In August 2017, two neutron stars were observed colliding, producing gravitational waves that were detected by the American LIGO and European Virgo detectors....
Up to now, OLEDs have been used exclusively as a novel lighting technology for use in luminaires and lamps. However, flexible organic technology can offer much more: as an active lighting surface, it can be combined with a wide variety of materials, not just to modify but to revolutionize the functionality and design of countless existing products. To exemplify this, the Fraunhofer FEP together with the company EMDE development of light GmbH will be presenting hybrid flexible OLEDs integrated into textile designs within the EU-funded project PI-SCALE for the first time at LOPEC (March 19-21, 2019 in Munich, Germany) as examples of some of the many possible applications.
The Fraunhofer FEP, a provider of research and development services in the field of organic electronics, has long been involved in the development of...
For the first time, an international team of scientists based in Regensburg, Germany, has recorded the orbitals of single molecules in different charge states in a novel type of microscopy. The research findings are published under the title “Mapping orbital changes upon electron transfer with tunneling microscopy on insulators” in the prestigious journal “Nature”.
The building blocks of matter surrounding us are atoms and molecules. The properties of that matter, however, are often not set by these building blocks...
Scientists at the University of Konstanz identify fierce competition between the human immune system and bacterial pathogens
Cell biologists from the University of Konstanz shed light on a recent evolutionary process in the human immune system and publish their findings in the...
Laser physicists have taken snapshots of carbon molecules C₆₀ showing how they transform in intense infrared light
When carbon molecules C₆₀ are exposed to an intense infrared light, they change their ball-like structure to a more elongated version. This has now been...
11.02.2019 | Event News
30.01.2019 | Event News
16.01.2019 | Event News
22.02.2019 | Physics and Astronomy
22.02.2019 | Materials Sciences
22.02.2019 | Life Sciences