Zebrafish embryo

A lateral view of a 4 days post-fertilisation Tg(Brn3a:GFP) embryo labelled with anti-GFP(green) to show expression of the transgene and anti-acetylated tubulin(red) to label neuronal tracts. this transgenic line labels beautifully the retinal ganglion cells in the retina and their projection to the optic tectum. It also labels the habenular nuclei in the epithalamus and all of the sensory neuromast cells including those in the ear. Neuromasts are hair cells and form the receptors of the lateral line system that senses vibration.