Figure 4.
Axonal localization of GFP-3′-β-actin product in central axons. Confocal images from spinal cord of Tα1-GFP-3′-β-actin (A–H) and Tα1-GFP-3′-γ-actin (I–L) mice at 10 d after thoracic spinal cord injury (SCI) (E–L) or sham procedure (A–D) are shown. Images were taken caudal to the injury site to capture central processes of DRGs. Images are matched for laser energy, gain, offset, and postprocessing. Top two rows show average projections of Z stacks. Lower two rows are single optical planes through the center of the axoplasm of the axon indicated by the rectangles in A, E, and I (channel designations for each row are indicated on the left). No GFP signal was detectable in samples from Tα1-GFP-3′-γ-actin (I–L). GFP signals are easily seen in the Tα1-GFP-3′-β-actin after injury (E–H, arrows) and low GFP signals are seen in the sham samples from Tα1-GFP-3′-β-actin mice (A–D, arrows). These GFP signals overlap with NF and are distinct from GFAP. Insets in B, F, and J show matched images for GFP signals in caudal DRGs. Scale bars: (A, B, E, F, I, J) 10 μm, (C, D, G, H, K, L) 20 μm.