Summary
The primary cilium (PC) is crucial for neuronal migration but the underlying cellular mechanisms are mostly unknown. Here, we show that ciliary-produced cAMP present at the centrosome locally activates cAMP-dependent Protein Kinase A (PKA). We analyzed cAMP dynamics through biosensor live-imaging in cyclic saltatory migrating neurons of the mouse postnatal rostral migratory stream. This revealed a dynamic cAMP hotspot cyclically present at the centrosome, thus located at the basis of the PC. Genetic ablation of the PC and knock-down of the ciliary Adenylate Cyclase 3 lead to the hotspot disappearance. They also affect migration with defective centrosome/nucleus coupling leading to altered nucleokinesis, which is recapitulated by PKA genetic delocalization. We thus show that PC and centrosome act as a single signaling unit, linked by ciliary cAMP diffusion regulating the rhythmicity of saltatory migration at the centrosome. We generalized this finding to embryonic and adult migrating neurons.
