Neuronal soma migration is determined by neurite tension

Neuronal migration is an intricate process involving a wide range of cellular mechanisms, some of which are still largely unknown. Using specially prepared culturing substrates, we were able to explore this and other developmental processes in networks composed of cultured locust neurons, and to analyze the role of neurite tension in these processes. Time lapse investigation shows that the shape and position of the cell soma are both linked to the extent and direction of the combined tension in its neurites. In particular, for migrating neurons (over 1-2 days) with three main neurites, a force-balance between neurite tension forces was demonstrated (σ F=0). The results presented here suggest that neuronal migration is strongly affected by tension in neurites rather than being entirely determined by the interaction between soma and substrate. The validity of these results to other in-vitro and in-vivo data is discussed.