Scientists unwrap DNA packaging to gain insight into cells

Scientists have built a clearer picture of how lengthy strands of DNA are concertinaed when our cells grow and divide, in a discovery that could help explain how cell renewal can go wrong.

Scientists have identified thousands of proteins that play a key role in compacting DNA – a crucial process by which DNA is shortened up to 10,000 times to fit inside cells as they split into two.

Researchers hope the findings could shed light on what happens when this packaging process fails and cells divide abnormally – which can lead to cancer or cause developing embryos to miscarry.

Scientists developed a new technology for their research by combining existing techniques in biology, genetics and maths and the large-scale study of proteins. They were able to define some 4,000 proteins involved in the division of cells. The proteins protect the fragile genetic material and help it fold into the correct shape before it splits into two new cells. The new methods can identify many of those proteins that are most important to the process.

University of Edinburgh scientists, who carried out the study, hope the discovery will help them better understand how these proteins influence the process of cell division.

The research was directed by Professors Juri Rappsilber and William Earnshaw, of the University of Edinburgh's School of Biological Sciences, and carried out in collaboration with the University of Oxford and the Japanese National Institute of Genetics in Mishima, Japan. It was supported by the Wellcome Trust and published in the journal Cell.

Until now, our understanding of the very complex way in which DNA moves during cell division was patchy; this latest development allows us, for the first time, to fully identify all the proteins that take part in the process, and how they interact with one another. Future work is needed to reveal more of the intricacies of this process and how to prevent it from going wrong.

Professor William Earnshaw

School of Biological Sciences

Images are taken from the original publication: The Protein Composition of Mitotic Chromosomes Determined Using Multiclassifier Combinatorial Proteomics authored by S. Ohta, J-C. Bukowski-Wills, L. Sanchez-Pulido, F. de L. Alves, L. Wood, Z.A. Chen, M. Platani, L. Fischer, D.F. Hudson, C.P. Ponting, T. Fukagawa, W.C. Earnshaw and J. Rappsilber. Cell 142(5), 810-821 (2010)

For more information please contact:

Professor William Earnshaw, School of Biological Sciences, tel 0131 650 7101; email

Professor Juri Rappsilber, tel 0131 651 7056; email

Catriona Kelly, Press and PR Office, tel 0131 651 4401; email