Our cells are bustling with traffic. Precious chemicals hurtle down microscopic tracks called microtubules pushed along by motor proteins, millions of times per day. Pictured on the left, a man-made network of red-coloured microtubules looks yellow-ish under a microscope – it’s been loaded with a cargo of green fluorescent proteins. On the right, a burst of chemical energy kick-starts motor proteins, sending the green cargo speeding towards the centre of the picture (bright yellow). This tiny rail system (roughly 1.5 billion times smaller than the London underground) took just seconds to assemble in a tube, using ‘instructions’ encoded in DNA. Self-assembling nanostructures might one day be developed for all sorts of uses, from industrial building materials to placement back inside living tissues, allowing the release of drugs at vulnerable ‘stations’ inside cancerous cells.
Written by John Ankers
BPoD stands for Biomedical Picture of the Day. Managed by the MRC London Institute of Medical Sciences the website aims to engage everyone, young and old, in the wonders of biomedicine. Images are kindly provided for inclusion on this website through the generosity of scientists across the globe.