How zebrafish forms its stripes revealed

Washington: A new research has revealed that three major pigment cell types i.e. black cells, reflective silvery cells, and yellow cells helped in forming the stripes on zebrafish.

The research conducted by Max Planck Institute for Developmental Biology in Tubingen showed that the yellow cells undergo dramatic changes in cell shape to tint the stripe pattern of zebrafish.

First author Prateek Mahalwar said that they were surprised to observe such cell behaviours, which were totally unexpected color pattern formation.

The study revealed that the three cell types reached the skin by completely different routes. A pluripotent cell population situated at the dorsal side of the embryo gave rise to larval yellow cells, which covered the skin of the embryo and began to multiply at the onset of metamorphosis when the fish was about two to three weeks old.

However, the black and silvery cells came from a small set of stem cells, which is associated with nerve nodes located close to the spinal cord in each segment.

Brigitte Walderich, a co-author of the Science paper, explained that they were surprised to discover that the small clusters of fluorescently labelled cells in the embryo, which could be followed during larval and juvenile stages to unravel growth and behaviour of the yellow cells, divided and multiplied as differentiated cells to cover the skin of the fish before the silvery and black cells arrive to form the stripes.

The study is published in journal Science.