Figure 4. Wnd/JNK/Fos injury signaling... | Rockefeller University Press

Figure 4.

$Figure 4. Wnd/JNK/Fos injury signaling is required for axonal sprouting after injury. (A–E) Axons are labeled by driving expression of UAS-mCD8-GFP by m12-Gal4 (A–C) and RRa(eve)-Gal4 (D and E). (A) In WT animals, the proximal stump forms extensive new branches (arrows) by 14 h after injury. (B) Sprouting after injury is inhibited by expression of wnd-RNAi, JNKDN, or FosDN in the GFP-labeled neurons. (C) Quantification of regeneration ratio 14 h after injury. The fraction of injured axons that exhibited sprouting was measured for at least 100 axons per genotype while blinded to the genotype. (D) At 24 h after injury, branches from the proximal stump are even longer in the WT background; however, this sprouting remains strongly inhibited in the wnd1/wnd2 mutant background. Bar, 25 µm. (E) Quantification of the regeneration ratio for WT and wnd1/2 at 14 and 24 h after injury, conducted similarly as in C. ***, P < 0.0001. Error bars indicate mean ± SEM.$

Wnd/JNK/Fos injury signaling is required for axonal sprouting after injury. (A–E) Axons are labeled by driving expression of UAS-mCD8-GFP by m12-Gal4 (A–C) and RRa(eve)-Gal4 (D and E). (A) In WT animals, the proximal stump forms extensive new branches (arrows) by 14 h after injury. (B) Sprouting after injury is inhibited by expression of wnd-RNAi, JNK^DN, or Fos^DN in the GFP-labeled neurons. (C) Quantification of regeneration ratio 14 h after injury. The fraction of injured axons that exhibited sprouting was measured for at least 100 axons per genotype while blinded to the genotype. (D) At 24 h after injury, branches from the proximal stump are even longer in the WT background; however, this sprouting remains strongly inhibited in the wnd¹/wnd² mutant background. Bar, 25 µm. (E) Quantification of the regeneration ratio for WT and wnd^1/2 at 14 and 24 h after injury, conducted similarly as in C. ***, P < 0.0001. Error bars indicate mean ± SEM.