Figure 9.

Growth and pruning of the Odd neural arbor during the first 48 hours of metamorphosis. All images are posterior views of the brain and maximum intensity projections (×40 magnification). A–E: Projections into the optic lobe. All images are composed of 10 confocal sections (total depth 20 μm). Neuropil is stained with nc82 antibody (magenta) and the Odd projections are labeled by GFP in green. A: In the first 2 hours after pupation the projections are disorganized, closely resembling that seen in the late larvae. They appear as mossy fibers. B: At 8 hours the first actual neurite can be seen (white arrow). C–E: The neurites extend while beginning to make arbors within the LP. The arbor is fully grown by 48 hours of pupation (E). The growth of the projections appears to follow closely behind the developing optic lobe. F–J: Pruning of the projections into the calyx during the first 48 hours after pupation. Brains were stained with Fas II antibody (magenta) and images are close-up views (×40 magnification) of the calyx (dashed lines). F: During the first 2 hours of pupation the Odd arbor in the calyx appear normal. G–J: Over the next 20 hours the arbor is progressively pruned away until only one branch remains (H,I). J: By 48 hours branches have been added again and branch addition is complete. K–O: Growth of the IPR, VMPR, VLPR, and PLPR arbor during the first 48 hours after pupation. Neuropil is stained with nc82 antibody (magenta). K: In the first 2 hours after onset of metamorphosis the arbor is small and compact. L–O: Over the next 46 hours the arbor grows bigger and more complex (O). Scale bar = 50 μm in A (applies to A–E), F (applies to F–J), and K (applies to K–O). [Color figure can be viewed in the online issue, which is available at wileyonlinelibrary.com.]