Light Touch

Like a cluster of Christmas fairy lights, this mosaic of colour is made of cells that have been genetically changed to produce fluorescent proteins. In the glare of a rapidly pulsing laser beam, cells in living tissue – the example here is a slice of spinal cord from a chicken embryo – glow in hues of red, blue and green. Scientists can then see how they behave in different circumstances, for example when tissue is being created, repaired or becomes diseased. This image is taken from a time-lapsed 3D video sequence of developing nerve cells. To be able to see all three colours simultaneously in real time pulses of laser light are synchronised to only a few millionths of a billionth of a second in duration, a feat possible only with recent advances in technology.

Written by Mick Warwicker

• Emmanuel Beaurepaire
• Laboratory for Optics and Biosciences, Ecole Polytechnique, France
• Reprinted by permission from Macmillan Publishers Ltd: Nature Methods Copyright 2012
• Published in Nature Methods 9: 815–818