The importance of Nav2 availability in promoting cytoskeletal remodeling during neuronal development is highlighted by the defasciculation and positional/survival phenotypes in C. elegans, by a reduction in hypothalamus size in Nav2 knock-out mice84, as well as the presence of brain malformations in human subjects carrying a biallelic truncated Nav2 isoform84. Here, NAV2 is linked to cerebral malformation.