BPoD has moved!

BPoD has recently changed our domain name - we can now be found at bpod.org.uk

Please update your bookmarks!

Now in our 13th year of bringing you beautiful imagery from biomedical science every day

Search the archive of over 4000 images

Balls of String
28 October 2012

Balls of String

Inside each of our cells roughly two metres of DNA is packed into a nucleus a thousand times smaller than this full stop. There’s even room to spare – so how does it all fit in? This image from a computer simulation shows how it’s done – special proteins intertwine with the DNA forming a compact structure called chromatin. Over time (moving from left to right in this picture), different proteins (shown here in red and green) pinch together specific areas of DNA (shown in grey), creating loops. These loops are wound tighter as more and more proteins attach, resulting in the neat, compact balls of chromatin on the right. But this isn’t long-term storage – some chromatin loops unravel every few seconds to allow genes on our DNA to be read or repaired before winding up again.

Written by John Ankers

Search The Archive

Submit An Image

Follow on Tumblr

Follow on Instagram

What is BPoD?

BPoD stands for Biomedical Picture of the Day. Managed by the MRC Laboratory of Medical Sciences until Jul 2023, it is now run independently by a dedicated team of scientists and writers. The website aims to engage everyone, young and old, in the wonders of biology, and its influence on medicine. The ever-growing archive of more than 4000 research images documents over a decade of progress. Explore the collection and see what you discover. Images are kindly provided for inclusion on this website through the generosity of scientists across the globe.

Read More

BPoD is also available in Catalan at www.bpod.cat with translations by the University of Valencia.