How neuronal and glial fates are specified from neural precursor cells is an important question for developmental neurobiologists. We address this question in the Drosophila optic lobe, composed of the lamina, medulla, and lobula complex. We show that two gliogenic regions posterior to the prospective lamina also produce lamina wide-field (Lawf) neurons, which share common progenitors with lamina glia. These progenitors express neither canonical neuroblast nor lamina precursor cell markers. They bifurcate into two sub-lineages in response to Notch signaling, generating lamina glia or Lawf neurons, respectively. The newly born glia and Lawfs then migrate tangentially over substantial distances to reach their target tissue. Thus, Lawf neurogenesis, which includes a common origin with glia, as well as neuronal migration, resembles several aspects of vertebrate neurogenesis. Chen et al. report an unusual class of progenitor cells, which bifurcate into lineages of migrating lamina glia and migrating Lawf neurons. The common progenitors differ from typical Drosophila neuroblasts. The Notch pathway mediates the fate choice between the glial and neuronal precursors, resembling the glia/neuron fate choice in vertebrates.
ASJC Scopus subject areas
- Biochemistry, Genetics and Molecular Biology(all)