Fig. 2. Neural stem cell niche. (A) Drosophila larval neuroblast (NB) niche. (Left) Schematic showing NB/glial contact (light blue bars) and cadherin-rich NB/ganglion mother cell (GMC) contacts (red bars). (Right) Confocal image showing glial membrane staining relative to neuroblast and GMC membranes. Glial membrane was detected with repo-gal4 UAS-cd8:GFP (blue, or as a single channel in the right-hand image). NB, GMC and neuronal membranes were labeled with Scribbled (red). Image courtesy of Jason Q. Boone (University of Oregon). (B) Mammalian neuroepithelia/radial glia niche. (Left) Neuroepithelial/radial glia cells contact the ventricular fluid at their apical domain (green dots), neighboring cells via cadherin-rich adherens junctions (AJs; red bars), and the basal lamina at their basal domain (dashed lines). Basal progenitors (BP; orange) and neurons (n; red) lack access to apical and basal cues. (Right) E10 mouse neuroepithelial cells showing cadherin enrichment at the subapical AJs (red) and prominin 1 localization to the apical domain (green) that contacts the ventricular fluid [modified and reproduced with permission from Kosodo et al. (Kosodo et al., 2004)].