Arl13b-regulated cilia activities are essential for polarized radial glial scaffold formation

Joubert syndrome, a recessive neurodevelopmental disorder associated with cortical malformations and autism-like features, has been linked to mutations in the gene encoding Arl13b, a cilia-enriched small GTPase. Here, Higginbotham and colleagues show that the early loss of function of Arl13b in mouse cortical progenitors leads to deficits in progenitors' ciliary signaling, apical–basal inversion of the radial glial scaffold and neuronal misplacement.