The calcium ion regulatesmanyaspects of neuronalmigration,which is an indispensable process in the development of the nervous system. Calmodulin (CaM) is a multifunctional calcium ion sensor that transduces much of the signal. To better understand the role of Ca-CaM in neuronal migration, we investigated mouse precerebellar neurons (PCNs), which undergo stereotyped, long-distance migration to r...