How the genome keeps out unwanted intruders
Scientists are a step closer to understanding the information in our genome thanks to pioneering research carried out at the Babraham Institute. In a new paper, scientists at the BBSRC strategically-funded institute provide insights into how the genome may defend itself from unwanted intruders.
The human genome is very large but only 1% of it consists of genes. Much of the remaining 99% is often considered 'junk' DNA, but junk DNA has been found to produce copious amounts of a molecule called RNA, which is normally associated with genes.
Now scientists working in a Wellcome Trust-funded laboratory at the Babraham Institute have shown that RNA produced by junk DNA has an important function; as a self defence mechanism allowing cells to prevent genetic 'intruders' from sneaking into the genome.
Why do cells need to do this? Much of the junk DNA in the genome comes from genetic parasites called transposable elements, which can eventually interfere with the normal function of the genome.
A process called RNA interference (RNAi) can recognise and silence transposable elements, but needs to distinguish them from the rest of the genome.
This research shows that RNA interference can use RNA from junk DNA to identify transposable elements as they spread through the genome, allowing the cell to detect invading parasites before they cause too much damage.
Dr Jon Houseley who directed the work said: "This work reveals the function of some of the more mysterious products of the genome, and helps us understand the consequences of genome alterations. For example, some normal genes can be amplified in cancer cells with dangerous consequences; our data reveals the existence of a mechanism by which cells can protect themselves against such changes."
Dr Michael Dunn, Head of Genetics and Molecular Sciences at the Wellcome Trust said: "Findings like these help us to understand the basis of our genome. Understanding the body's defence mechanisms at the molecular level can help inform development of new treatments and guide future research".
Director of the Babraham Institute, Professor Michael Wakelam, adds "Jon Houseley's group have not only provided a function for ill-defined regions of the genome, but have defined an essential integral self defence mechanism which has significant future potential to define novel therapeutic targets for a range of diseases, including cancer. In addition, this work addresses changes that can occur during the ageing process. This work clearly demonstrates the outstanding opportunities presented through continuing support for basic bioscience research as carried out at the Babraham Institute."
About the Babraham Institute
The Babraham Institute, which receives strategic funding (£23.1M from 2012-2013) from the Biotechnology and Biological Sciences Research Council (BBSRC), undertakes international quality life sciences research to generate new knowledge of biological mechanisms underpinning ageing, development and the maintenance of health. The Institute's research provides greater understanding of the biological events that underlie the normal functions of cells and the implication of failure or abnormalities in these processes. Research focuses on signalling and genome regulation, particularly the interplay between the two and how epigenetic signals can influence important physiological adaptations during the lifespan of an organism. By determining how the body reacts to dietary and environmental stimuli and manages microbial and viral interactions, we aim to improve wellbeing and healthier ageing. www.babraham.ac.uk
Tags: The Babraham Institute genetics human health press release