Figure 4.

Sodium channel clustering in Schwann cell-deficient peripheral nerves is inhibited by knockdown of ankyrin G but not neurofascin. A, Embryos from erbb2 ^st61/+ heterozygous intercrosses were injected with water or with MO against the neural-specific transcript of ank3a or with MO against neurofascin. The average number of sodium channel clusters per PLLn is shown at 72 hpf (error bars indicate ±1 SD). The p values for unpaired t test (single-tailed) comparisons are shown. One PLLn was scored per embryo, and the number of embryos scored from left to right is 18, 20, 20, 15, 20, and 21. B–D, Water-injected wild-type sibling (B), nfasc MO-injected wild-type sibling (C), and nfasc MO-injected erbb2^st61 mutant (D) at 72 hpf, immunolabeled with anti-panNa_vCh (green) and anti-extracellular neurofascin (red). Neurofascin is shown alone in B′–D′. E, F, Wild-type 72 hpf embryos injected with water (E) or neurofascin MO (F) labeled with anti-acetylated tubulin (red) and anti-FIGQY (recognizes intracellular epitope of neurofascin, green).