Fig. 4
TNFa is required for axonal ensheathment by DREZ glia.
(A) Images of wildtype, tnfa morphant and tnfa F0 CRISPR mutant Tg(sox10:eos) larvae at 72 hpf. Arrow denotes central branch that is ensheathed by sox10+ glia in wildtype but not tnfa morphants or tnfa F0 CRISPR mutants. (B) Quantification of data from panel A, wt n = 40 DRG, tnfa MO n = 54 DRG. (C) Electron microscopy images of DRG tissue from wildtype and TNF-/- P0 pups showed a reduction in the ensheathment of axonal bundles. (n = 3 animals/genotype). (D,E) Quantification of ensheathed vs unensheathed bundles in wildtype and TNF-/- pups (3 animals, wt n = 108 nerve bundles, TNFR2-/- n = 85 nerve bundles). (F,G) Quantification of the number of axons per small-caliber bundle in wildtype and TNF-/- pups. (H) Images of spinal column tissue from wildtype and TNF-/- P0 embryo labeled with antibodies to S100 (green) and βIII Tubulin (red). Traced area denotes central projection that extends into the spinal cord. In TNF-/- pups, the central afferent lacks S100 staining. Fisher’s exact test (B,E,G). Students t-test (D,F). Scale bars, 25 μm (A,H), 5 μm (C).