Our DNA and its architecture are duplicated every time our cells divide.
Histone proteins are key building blocks of this architecture and contain crucial information that regulates our genes. Danish researchers show how an enzyme controls reliable and high-speed delivery of histones to DNA copying hubs in our cells. This shuttling mechanism is crucial to maintain normal function of our genes and prevent disease. The results are published in the journal Nature Communications.
This is Ilnaz Klimovskaia in the lab.
Credit: Anja Groth, BRIC
Interdisciplinary research team finds cellular high-speed shuttle
An interdisciplinary team of researchers from BRIC, University of Copenhagen and University of Southern Denmark have identified a cellular transport mechanism so fast and finely tuned that it compares to an Asian fast-speed train.
"Using advanced laboratory techniques, we have revealed how an enzyme called TLK1 regulates the transport of histones to DNA copying hubs in our cells. Such a devoted supply of histones, is crucial to maintain the genomic architecture when our cells divide", says Ilnaz Klimovskaia who has been spearheading the experimental work as part of her PhD-studies at BRIC.
The new results show that TLK1 controls the activity of a molecule called Asf1. Asf1 act as a freight train that transports histones to the nuclei of our cells where the DNA is copied during cell divisions. The enzymatic activity of TLK1 turn Asf1 into a fast-speed train, capable of precise, fast and timely transport of histones to newly formed DNA.
TLK1 contribute to cellular identity
Histones play an important role for the activity of our genes, as they contain information that can turn on or off genes. The information is communicated only when DNA is wrapped around the histones, to form the ordered genomic architecture called chromatin. As all our cells contain exactly the same genes, the histone information is crucial to activate only the sub-set of genes necessary to maintain a certain cellular identity. For example, heart genes needs only to be turned on in heart cells, but turned off in other cell types.
"We show that TLK can boost the supply of histones at critical time points. By controlling the transport of histones to our DNA, TLK and Asf1 ensure that the chromatin architecture and its information are copied correctly during cell division, so that cell identity is maintained", explains Ilnaz Klimovskaia.
Loss of chromatin integrity in cancer development
A tight coordination between DNA duplication and supply of major chromatin building blocks like histones, are crucial to maintain normal function of our cells. If the chromatin architecture is wrong, it can affect both gene expression as well as the stability of our DNA. Together, this is a dangerous cocktail that might fuel cellular changes and lead to cancer development.
"Our research adds a new layer to the understanding of how chromatin is maintained when cells in our body divides. This information is crucial to understand how cells maintain their identity and protect their genome, which is essential to avoid cancer development", says associate professor Anja Groth, who has been heading the research team.
The next step for the research team is to dig deeper into the understanding of how chromatin duplication is controlled. The team is also exploring whether targeting of the TLK enzyme could be useful in cancer therapy, as they speculate that reducing the supply of histones in highly dividing cancer cells, might make tumor cells more vulnerable to already existing cancer drugs.
Katrine Sonne-Hansen | EurekAlert!
Two decades of training students and experts in tracking infectious disease
27.11.2015 | Hochschule für Angewandte Wissenschaften Hamburg
Increased carbon dioxide enhances plankton growth, opposite of what was expected
27.11.2015 | Bigelow Laboratory for Ocean Sciences
Planet Earth experienced a global climate shift in the late 1980s on an unprecedented scale, fuelled by anthropogenic warming and a volcanic eruption, according to new research published this week.
Scientists say that a major step change, or ‘regime shift’, in the Earth’s biophysical systems, from the upper atmosphere to the depths of the ocean and from...
The Fraunhofer Institute for Solar Energy Systems ISE has installed 70 photovoltaic modules on the outer façade of one of its lab buildings. The modules were...
Nerve cells cover their high energy demand with glucose and lactate. Scientists of the University of Zurich now provide new support for this. They show for the first time in the intact mouse brain evidence for an exchange of lactate between different brain cells. With this study they were able to confirm a 20-year old hypothesis.
In comparison to other organs, the human brain has the highest energy requirements. The supply of energy for nerve cells and the particular role of lactic acid...
In laser material processing, the simulation of processes has made great strides over the past few years. Today, the software can predict relatively well what will happen on the workpiece. Unfortunately, it is also highly complex and requires a lot of computing time. Thanks to clever simplification, experts from Fraunhofer ILT are now able to offer the first-ever simulation software that calculates processes in real time and also runs on tablet computers and smartphones. The fast software enables users to do without expensive experiments and to find optimum process parameters even more effectively.
Before now, the reliable simulation of laser processes was a job for experts. Armed with sophisticated software packages and after many hours on computer...
Researchers at Heidelberg University have devised a new way to study the phenomenon of magnetism. Using ultracold atoms at near absolute zero, they prepared a...
25.11.2015 | Event News
17.11.2015 | Event News
21.10.2015 | Event News
27.11.2015 | Press release
27.11.2015 | Life Sciences
27.11.2015 | Materials Sciences