Researchers have created a transgenic zebrafish with skin that fluoresces in thousands of colours — enabling them to track the behaviour of hundreds of individual cells in real time.

Credit: Chen et al./Dev. Cell (2016)

Kenneth Poss at Duke University Medical Center in Durham, North Carolina, and his colleagues adapted a 'brainbow' technique published in 2007, which engineered neurons to express different mixtures of fluorescent proteins. The team made the skin cells of zebrafish express the proteins so that cells could appear in one of around 5,000 different colours. About 70 could be distinguished clearly through a microscope — enough for most cells to be made distinct from their neighbours (pictured).

Using this 'skinbow' method, the team found that skin cells responded in three ways to fin amputation: cells from nearby regions migrated in to cover the new tissue; new skin cells were created; and some skin cells grew in size.

Dev. Cell 36, 668–680 (2016)