Neuronal Support Cells Get the Message

During motor neuron development in zebrafish, a class of glial (support) cells, called perineurial glia, migrates out of the spinal cord based on signals that have been unknown until now.  Sarah Kucenas and colleagues at the University of Virginia showed in new work, published this week in the Journal of Neuroscience, that the Notch signaling pathway plays a role in correct migration of perineurial glia and in the differentiation of Schwann cells, the cells that ensheath nerve axons. Using the zebrafish embryo, which is optically clear, the researchers visualized Notch signaling and cell migration in real time, generating convincing and beautiful evidence that perineurial glia rely on Notch signaling to move the long distances necessary for their function.