©Mubarak Hussain Syed

The ability of stem cells to generate neuronal diversity has fascinated researchers, but the mechanisms that drive these pathways have so far remained elusive.

Syed et al. looked at embryonic development in Drosophila to examine the sequence of gene expression and the mechanism by which the neural stem cells switch from expressing one gene to the next. They found that a steroid hormone called ecdysone is critical to triggering one of these vital transitions in gene expression during early brain development. Ecdysone appears to alter expression in a number of genes, downregulating Chinmo/Imp and activating Syncrip. The timing of this is important, as it coincides with an important time frame in brain development, where the number and identity of different neurones required to complete brain formation are set.

This is the first example of hormones regulating time-sensitive gene transitions during neurogenesis. The researchers hope this discovery will provide some insight into the role of hormone signalling in neurological diseases.

Read the full article in eLife 6 e26287 (OA)