Fig. 5

TNFa/TNFR2-mediated signaling is active in pioneer axon-associated glia.

(A) Images and schematic of Tg(NFkB:egfp);Tg(sox10:mrfp) embryos at 72 hpf showing GFP⁺ glia at the DREZ. (B) Quantification of the percentage of DRG with Tg(NFkB:egfp) expression at 48 and 72 hpf, n = 30 DRG. (C) Quantification of NFkB⁺ DREZ glia along pioneer axons that were axotomized before entry (pre-entry), after entry (post-entry), non-ablated and peripheral axotomy (n = 8 nerves/condition). (D) Intensity profiles of GFP in Tg(NFkB:egfp);Tg(sox10:mrfp) embryos from 48 to 72 hpf showing GFP upregulation upon axon entry into the spinal cord. Shown is the average of 2 movies normalized for the time of entry. (E) Images of Tg(NFkB:egfp) embryos in wildtype, tnfa morphant and tnfr2 morphant larvae showing NFkB activation is dependent on tnfa and tnfr2. (F) Quantification of data from panel D, SEM is shown, wt n = 30 DRG, tnfa MO n = 30 DRG, tnfr2 MO n = 30 DRG. Scale bars, 25 μm.