Characterisation of the zebrafish cerebellar efferent system.

The efferent system of the cerebellum is formed by the neurons of the deep cerebellar nuclei. Using morphology and expression analysis together with axon tracing I have identified and characterised this cell population, the Eurydendroid cells (ECs), in the zebrafish. With the help of transgenic lines expressing fluorescent proteins and in vivo time lapse analysis I have revealed the developmental period, their differentiation behaviour and their integration into the layered cerebellar cortex. Finally nmyc expression and its regulation were identified as a potential key factor in EC proliferation or specification. These results significantly expand our knowledge of cerebellar development in teleosts and their use as informative disease models