Confocal microscope image of GFP-tagged Merlin (green), the Drosophila Neurofibromatosis 2 tumor-suppressor homologue, in the larval salivary gland. The Merlin protein is cytoplasmic but closely associated with the plasma membrane in the apical end of epithelial cells. The salivary gland is a single-layered epithelial tube, with the apical surface toward the lumen of the tube. The polytene chromosomes in the nuclei are stained with propidium iodide (red). (From the laboratory of Richard Fehon)

Confocal microscope image of GFP-tagged Merlin (green), the Drosophila Neurofibromatosis 2 tumor-suppressor homologue, in the larval salivary gland. The Merlin protein is cytoplasmic but closely associated with the plasma membrane in the apical end of epithelial cells. The salivary gland is a single-layered epithelial tube, with the apical surface toward the lumen of the tube. The polytene chromosomes in the nuclei are stained with propidium iodide (red). (From the laboratory of Richard Fehon)