Fig. 6.
Overexpression of Mmp2 degrades the neural lamella and causes a perineurial glial wrapping defect. 46F-GAL4 was used to express CD8-RFP (red) and UAS-Mmp2 in the PG. Expression was regulated by a temperature-sensitive GAL80 under the control of a ubiquitous tubulin promoter (tubP-GAL80ts). The NL was labeled by Perlecan-GFP (green) and γ-Laminin (blue). The labeling and changes to the NL and PG are also illustrated beneath. (A,B,F,G) Single 0.2 μm z-sections of the nerves; (C,H) projections of the entire z-stack. Boxed regions were digitally expanded as shown in D and I. (E,J) Orthogonal sections of z-stacks from the positions indicated by the green lines. (A-E) In a control nerve, Perlecan-GFP (green) and γ-Laminin (blue) labeled the outermost NL (arrows), which surrounds the CD8-RFP-labeled PG (red). Diffuse, low-level Laminin staining was apparent within the nerve. (F-J) In a 46F::Mmp2 nerve, both Perlecan-GFP (green) and γ-Laminin immunolabeling (blue) indicate that the remaining NL is partially detached from the surface of the nerve (arrows). γ-Laminin immunolabeling appeared to be increased within the CD8-RFP-labeled (red) PG (arrowheads). The PG no longer wrapped around the entire circumference of the nerve and borders of distinct, individual PG were identified. Scale bars: 10 μm in A-C,F-H; 5 μm in D,E,I,J.