Each summer, scientists gather in Woods Hole, Massachusetts to conduct research and take courses at the Marine Biological Laboratory. Last year, MBL held a scientific photography contest that anyone involved with the institution was allowed to enter. The winner, Albert Pan, a post-doc at Harvard University and a teaching assistant for MBL's zebrafish course, won first place with the image above, "Brainbow Zebrafish Embryo."
This image shows a one-day-old zebrafish embryo shown from the side. Rostral is left and caudal is right. Different cell types are labeled by random mixing of three fluorescent proteins, red, green, and blue. This image is a montage of several confocal images taken at the imaging facility at the Center for Brain Science at Harvard University.
The multiple colors were created using something called the brainbow technique, which was created in 2007 and is used to label neurons. The blog Neurophilosophy has a detailed explanation, starting with:
Researchers from Harvard University have developed a remarkable genetic technique that enabled them to visualize complete neuronal circuits in unprecedented detail, by using multiple distinct colours to label individual neurons.
The technique, called Brainbow, works in much the same way as a television uses the three primary colours to generate all the colour hues. With multiple combinations of up to four differently coloured fluorescent proteins, a palette of approximately 100 labels has been produced.
Useful and pretty.